1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 1986, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright 2015, Joyent, Inc. All rights reserved.
24 * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
25 */
26
27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29
30 /*
31 * University Copyright- Copyright (c) 1982, 1986, 1988
32 * The Regents of the University of California
33 * All Rights Reserved
34 *
35 * University Acknowledgment- Portions of this document are derived from
36 * software developed by the University of California, Berkeley, and its
37 * contributors.
38 */
39
40 /*
41 * VM - shared or copy-on-write from a vnode/anonymous memory.
42 */
43
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/t_lock.h>
47 #include <sys/errno.h>
48 #include <sys/systm.h>
49 #include <sys/mman.h>
50 #include <sys/debug.h>
51 #include <sys/cred.h>
52 #include <sys/vmsystm.h>
53 #include <sys/tuneable.h>
54 #include <sys/bitmap.h>
55 #include <sys/swap.h>
56 #include <sys/kmem.h>
57 #include <sys/sysmacros.h>
58 #include <sys/vtrace.h>
59 #include <sys/cmn_err.h>
60 #include <sys/callb.h>
61 #include <sys/vm.h>
62 #include <sys/dumphdr.h>
63 #include <sys/lgrp.h>
64
65 #include <vm/hat.h>
66 #include <vm/as.h>
67 #include <vm/seg.h>
68 #include <vm/seg_vn.h>
69 #include <vm/pvn.h>
70 #include <vm/anon.h>
71 #include <vm/page.h>
72 #include <vm/vpage.h>
73 #include <sys/proc.h>
74 #include <sys/task.h>
75 #include <sys/project.h>
76 #include <sys/zone.h>
77 #include <sys/shm_impl.h>
78
79 /*
80 * segvn_fault needs a temporary page list array. To avoid calling kmem all
81 * the time, it creates a small (PVN_GETPAGE_NUM entry) array and uses it if
82 * it can. In the rare case when this page list is not large enough, it
83 * goes and gets a large enough array from kmem.
84 *
85 * This small page list array covers either 8 pages or 64kB worth of pages -
86 * whichever is smaller.
87 */
88 #define PVN_MAX_GETPAGE_SZ 0x10000
89 #define PVN_MAX_GETPAGE_NUM 0x8
90
91 #if PVN_MAX_GETPAGE_SZ > PVN_MAX_GETPAGE_NUM * PAGESIZE
92 #define PVN_GETPAGE_SZ ptob(PVN_MAX_GETPAGE_NUM)
93 #define PVN_GETPAGE_NUM PVN_MAX_GETPAGE_NUM
94 #else
95 #define PVN_GETPAGE_SZ PVN_MAX_GETPAGE_SZ
96 #define PVN_GETPAGE_NUM btop(PVN_MAX_GETPAGE_SZ)
97 #endif
98
99 /*
100 * Private seg op routines.
101 */
102 static int segvn_dup(struct seg *seg, struct seg *newseg);
103 static int segvn_unmap(struct seg *seg, caddr_t addr, size_t len);
104 static void segvn_free(struct seg *seg);
105 static faultcode_t segvn_fault(struct hat *hat, struct seg *seg,
106 caddr_t addr, size_t len, enum fault_type type,
107 enum seg_rw rw);
108 static faultcode_t segvn_faulta(struct seg *seg, caddr_t addr);
109 static int segvn_setprot(struct seg *seg, caddr_t addr,
110 size_t len, uint_t prot);
111 static int segvn_checkprot(struct seg *seg, caddr_t addr,
112 size_t len, uint_t prot);
113 static int segvn_kluster(struct seg *seg, caddr_t addr, ssize_t delta);
114 static size_t segvn_swapout(struct seg *seg);
115 static int segvn_sync(struct seg *seg, caddr_t addr, size_t len,
116 int attr, uint_t flags);
117 static size_t segvn_incore(struct seg *seg, caddr_t addr, size_t len,
118 char *vec);
119 static int segvn_lockop(struct seg *seg, caddr_t addr, size_t len,
120 int attr, int op, ulong_t *lockmap, size_t pos);
121 static int segvn_getprot(struct seg *seg, caddr_t addr, size_t len,
122 uint_t *protv);
123 static u_offset_t segvn_getoffset(struct seg *seg, caddr_t addr);
124 static int segvn_gettype(struct seg *seg, caddr_t addr);
125 static int segvn_getvp(struct seg *seg, caddr_t addr,
126 struct vnode **vpp);
127 static int segvn_advise(struct seg *seg, caddr_t addr, size_t len,
128 uint_t behav);
129 static void segvn_dump(struct seg *seg);
130 static int segvn_pagelock(struct seg *seg, caddr_t addr, size_t len,
131 struct page ***ppp, enum lock_type type, enum seg_rw rw);
132 static int segvn_setpagesize(struct seg *seg, caddr_t addr, size_t len,
133 uint_t szc);
134 static int segvn_getmemid(struct seg *seg, caddr_t addr,
135 memid_t *memidp);
136 static lgrp_mem_policy_info_t *segvn_getpolicy(struct seg *, caddr_t);
137 static int segvn_capable(struct seg *seg, segcapability_t capable);
138 static int segvn_inherit(struct seg *, caddr_t, size_t, uint_t);
139
140 struct seg_ops segvn_ops = {
141 segvn_dup,
142 segvn_unmap,
143 segvn_free,
144 segvn_fault,
145 segvn_faulta,
146 segvn_setprot,
147 segvn_checkprot,
148 segvn_kluster,
149 segvn_swapout,
150 segvn_sync,
151 segvn_incore,
152 segvn_lockop,
153 segvn_getprot,
154 segvn_getoffset,
155 segvn_gettype,
156 segvn_getvp,
157 segvn_advise,
158 segvn_dump,
159 segvn_pagelock,
160 segvn_setpagesize,
161 segvn_getmemid,
162 segvn_getpolicy,
163 segvn_capable,
164 segvn_inherit
165 };
166
167 /*
168 * Common zfod structures, provided as a shorthand for others to use.
169 */
170 static segvn_crargs_t zfod_segvn_crargs =
171 SEGVN_ZFOD_ARGS(PROT_ZFOD, PROT_ALL);
172 static segvn_crargs_t kzfod_segvn_crargs =
173 SEGVN_ZFOD_ARGS(PROT_ZFOD & ~PROT_USER,
174 PROT_ALL & ~PROT_USER);
175 static segvn_crargs_t stack_noexec_crargs =
176 SEGVN_ZFOD_ARGS(PROT_ZFOD & ~PROT_EXEC, PROT_ALL);
177
178 caddr_t zfod_argsp = (caddr_t)&zfod_segvn_crargs; /* user zfod argsp */
179 caddr_t kzfod_argsp = (caddr_t)&kzfod_segvn_crargs; /* kernel zfod argsp */
180 caddr_t stack_exec_argsp = (caddr_t)&zfod_segvn_crargs; /* executable stack */
181 caddr_t stack_noexec_argsp = (caddr_t)&stack_noexec_crargs; /* noexec stack */
182
183 #define vpgtob(n) ((n) * sizeof (struct vpage)) /* For brevity */
184
185 size_t segvn_comb_thrshld = UINT_MAX; /* patchable -- see 1196681 */
186
187 size_t segvn_pglock_comb_thrshld = (1UL << 16); /* 64K */
188 size_t segvn_pglock_comb_balign = (1UL << 16); /* 64K */
189 uint_t segvn_pglock_comb_bshift;
190 size_t segvn_pglock_comb_palign;
191
192 static int segvn_concat(struct seg *, struct seg *, int);
193 static int segvn_extend_prev(struct seg *, struct seg *,
194 struct segvn_crargs *, size_t);
195 static int segvn_extend_next(struct seg *, struct seg *,
196 struct segvn_crargs *, size_t);
197 static void segvn_softunlock(struct seg *, caddr_t, size_t, enum seg_rw);
198 static void segvn_pagelist_rele(page_t **);
199 static void segvn_setvnode_mpss(vnode_t *);
200 static void segvn_relocate_pages(page_t **, page_t *);
201 static int segvn_full_szcpages(page_t **, uint_t, int *, uint_t *);
202 static int segvn_fill_vp_pages(struct segvn_data *, vnode_t *, u_offset_t,
203 uint_t, page_t **, page_t **, uint_t *, int *);
204 static faultcode_t segvn_fault_vnodepages(struct hat *, struct seg *, caddr_t,
205 caddr_t, enum fault_type, enum seg_rw, caddr_t, caddr_t, int);
206 static faultcode_t segvn_fault_anonpages(struct hat *, struct seg *, caddr_t,
207 caddr_t, enum fault_type, enum seg_rw, caddr_t, caddr_t, int);
208 static faultcode_t segvn_faultpage(struct hat *, struct seg *, caddr_t,
209 u_offset_t, struct vpage *, page_t **, uint_t,
210 enum fault_type, enum seg_rw, int);
211 static void segvn_vpage(struct seg *);
212 static size_t segvn_count_swap_by_vpages(struct seg *);
213
214 static void segvn_purge(struct seg *seg);
215 static int segvn_reclaim(void *, caddr_t, size_t, struct page **,
216 enum seg_rw, int);
217 static int shamp_reclaim(void *, caddr_t, size_t, struct page **,
218 enum seg_rw, int);
219
220 static int sameprot(struct seg *, caddr_t, size_t);
221
222 static int segvn_demote_range(struct seg *, caddr_t, size_t, int, uint_t);
223 static int segvn_clrszc(struct seg *);
224 static struct seg *segvn_split_seg(struct seg *, caddr_t);
225 static int segvn_claim_pages(struct seg *, struct vpage *, u_offset_t,
226 ulong_t, uint_t);
227
228 static void segvn_hat_rgn_unload_callback(caddr_t, caddr_t, caddr_t,
229 size_t, void *, u_offset_t);
230
231 static struct kmem_cache *segvn_cache;
232 static struct kmem_cache **segvn_szc_cache;
233
234 #ifdef VM_STATS
235 static struct segvnvmstats_str {
236 ulong_t fill_vp_pages[31];
237 ulong_t fltvnpages[49];
238 ulong_t fullszcpages[10];
239 ulong_t relocatepages[3];
240 ulong_t fltanpages[17];
241 ulong_t pagelock[2];
242 ulong_t demoterange[3];
243 } segvnvmstats;
244 #endif /* VM_STATS */
245
246 #define SDR_RANGE 1 /* demote entire range */
247 #define SDR_END 2 /* demote non aligned ends only */
248
249 #define CALC_LPG_REGION(pgsz, seg, addr, len, lpgaddr, lpgeaddr) { \
250 if ((len) != 0) { \
251 lpgaddr = (caddr_t)P2ALIGN((uintptr_t)(addr), pgsz); \
252 ASSERT(lpgaddr >= (seg)->s_base); \
253 lpgeaddr = (caddr_t)P2ROUNDUP((uintptr_t)((addr) + \
254 (len)), pgsz); \
255 ASSERT(lpgeaddr > lpgaddr); \
256 ASSERT(lpgeaddr <= (seg)->s_base + (seg)->s_size); \
257 } else { \
258 lpgeaddr = lpgaddr = (addr); \
259 } \
260 }
261
262 /*ARGSUSED*/
263 static int
segvn_cache_constructor(void * buf,void * cdrarg,int kmflags)264 segvn_cache_constructor(void *buf, void *cdrarg, int kmflags)
265 {
266 struct segvn_data *svd = buf;
267
268 rw_init(&svd->lock, NULL, RW_DEFAULT, NULL);
269 mutex_init(&svd->segfree_syncmtx, NULL, MUTEX_DEFAULT, NULL);
270 svd->svn_trnext = svd->svn_trprev = NULL;
271 return (0);
272 }
273
274 /*ARGSUSED1*/
275 static void
segvn_cache_destructor(void * buf,void * cdrarg)276 segvn_cache_destructor(void *buf, void *cdrarg)
277 {
278 struct segvn_data *svd = buf;
279
280 rw_destroy(&svd->lock);
281 mutex_destroy(&svd->segfree_syncmtx);
282 }
283
284 /*ARGSUSED*/
285 static int
svntr_cache_constructor(void * buf,void * cdrarg,int kmflags)286 svntr_cache_constructor(void *buf, void *cdrarg, int kmflags)
287 {
288 bzero(buf, sizeof (svntr_t));
289 return (0);
290 }
291
292 /*
293 * Patching this variable to non-zero allows the system to run with
294 * stacks marked as "not executable". It's a bit of a kludge, but is
295 * provided as a tweakable for platforms that export those ABIs
296 * (e.g. sparc V8) that have executable stacks enabled by default.
297 * There are also some restrictions for platforms that don't actually
298 * implement 'noexec' protections.
299 *
300 * Once enabled, the system is (therefore) unable to provide a fully
301 * ABI-compliant execution environment, though practically speaking,
302 * most everything works. The exceptions are generally some interpreters
303 * and debuggers that create executable code on the stack and jump
304 * into it (without explicitly mprotecting the address range to include
305 * PROT_EXEC).
306 *
307 * One important class of applications that are disabled are those
308 * that have been transformed into malicious agents using one of the
309 * numerous "buffer overflow" attacks. See 4007890.
310 */
311 int noexec_user_stack = 0;
312 int noexec_user_stack_log = 1;
313
314 int segvn_lpg_disable = 0;
315 uint_t segvn_maxpgszc = 0;
316
317 ulong_t segvn_vmpss_clrszc_cnt;
318 ulong_t segvn_vmpss_clrszc_err;
319 ulong_t segvn_fltvnpages_clrszc_cnt;
320 ulong_t segvn_fltvnpages_clrszc_err;
321 ulong_t segvn_setpgsz_align_err;
322 ulong_t segvn_setpgsz_anon_align_err;
323 ulong_t segvn_setpgsz_getattr_err;
324 ulong_t segvn_setpgsz_eof_err;
325 ulong_t segvn_faultvnmpss_align_err1;
326 ulong_t segvn_faultvnmpss_align_err2;
327 ulong_t segvn_faultvnmpss_align_err3;
328 ulong_t segvn_faultvnmpss_align_err4;
329 ulong_t segvn_faultvnmpss_align_err5;
330 ulong_t segvn_vmpss_pageio_deadlk_err;
331
332 int segvn_use_regions = 1;
333
334 /*
335 * Segvn supports text replication optimization for NUMA platforms. Text
336 * replica's are represented by anon maps (amp). There's one amp per text file
337 * region per lgroup. A process chooses the amp for each of its text mappings
338 * based on the lgroup assignment of its main thread (t_tid = 1). All
339 * processes that want a replica on a particular lgroup for the same text file
340 * mapping share the same amp. amp's are looked up in svntr_hashtab hash table
341 * with vp,off,size,szc used as a key. Text replication segments are read only
342 * MAP_PRIVATE|MAP_TEXT segments that map vnode. Replication is achieved by
343 * forcing COW faults from vnode to amp and mapping amp pages instead of vnode
344 * pages. Replication amp is assigned to a segment when it gets its first
345 * pagefault. To handle main thread lgroup rehoming segvn_trasync_thread
346 * rechecks periodically if the process still maps an amp local to the main
347 * thread. If not async thread forces process to remap to an amp in the new
348 * home lgroup of the main thread. Current text replication implementation
349 * only provides the benefit to workloads that do most of their work in the
350 * main thread of a process or all the threads of a process run in the same
351 * lgroup. To extend text replication benefit to different types of
352 * multithreaded workloads further work would be needed in the hat layer to
353 * allow the same virtual address in the same hat to simultaneously map
354 * different physical addresses (i.e. page table replication would be needed
355 * for x86).
356 *
357 * amp pages are used instead of vnode pages as long as segment has a very
358 * simple life cycle. It's created via segvn_create(), handles S_EXEC
359 * (S_READ) pagefaults and is fully unmapped. If anything more complicated
360 * happens such as protection is changed, real COW fault happens, pagesize is
361 * changed, MC_LOCK is requested or segment is partially unmapped we turn off
362 * text replication by converting the segment back to vnode only segment
363 * (unmap segment's address range and set svd->amp to NULL).
364 *
365 * The original file can be changed after amp is inserted into
366 * svntr_hashtab. Processes that are launched after the file is already
367 * changed can't use the replica's created prior to the file change. To
368 * implement this functionality hash entries are timestamped. Replica's can
369 * only be used if current file modification time is the same as the timestamp
370 * saved when hash entry was created. However just timestamps alone are not
371 * sufficient to detect file modification via mmap(MAP_SHARED) mappings. We
372 * deal with file changes via MAP_SHARED mappings differently. When writable
373 * MAP_SHARED mappings are created to vnodes marked as executable we mark all
374 * existing replica's for this vnode as not usable for future text
375 * mappings. And we don't create new replica's for files that currently have
376 * potentially writable MAP_SHARED mappings (i.e. vn_is_mapped(V_WRITE) is
377 * true).
378 */
379
380 #define SEGVN_TEXTREPL_MAXBYTES_FACTOR (20)
381 size_t segvn_textrepl_max_bytes_factor = SEGVN_TEXTREPL_MAXBYTES_FACTOR;
382
383 static ulong_t svntr_hashtab_sz = 512;
384 static svntr_bucket_t *svntr_hashtab = NULL;
385 static struct kmem_cache *svntr_cache;
386 static svntr_stats_t *segvn_textrepl_stats;
387 static ksema_t segvn_trasync_sem;
388
389 int segvn_disable_textrepl = 1;
390 size_t textrepl_size_thresh = (size_t)-1;
391 size_t segvn_textrepl_bytes = 0;
392 size_t segvn_textrepl_max_bytes = 0;
393 clock_t segvn_update_textrepl_interval = 0;
394 int segvn_update_tr_time = 10;
395 int segvn_disable_textrepl_update = 0;
396
397 static void segvn_textrepl(struct seg *);
398 static void segvn_textunrepl(struct seg *, int);
399 static void segvn_inval_trcache(vnode_t *);
400 static void segvn_trasync_thread(void);
401 static void segvn_trupdate_wakeup(void *);
402 static void segvn_trupdate(void);
403 static void segvn_trupdate_seg(struct seg *, segvn_data_t *, svntr_t *,
404 ulong_t);
405
406 /*
407 * Initialize segvn data structures
408 */
409 void
segvn_init(void)410 segvn_init(void)
411 {
412 uint_t maxszc;
413 uint_t szc;
414 size_t pgsz;
415
416 segvn_cache = kmem_cache_create("segvn_cache",
417 sizeof (struct segvn_data), 0,
418 segvn_cache_constructor, segvn_cache_destructor, NULL,
419 NULL, NULL, 0);
420
421 if (segvn_lpg_disable == 0) {
422 szc = maxszc = page_num_pagesizes() - 1;
423 if (szc == 0) {
424 segvn_lpg_disable = 1;
425 }
426 if (page_get_pagesize(0) != PAGESIZE) {
427 panic("segvn_init: bad szc 0");
428 /*NOTREACHED*/
429 }
430 while (szc != 0) {
431 pgsz = page_get_pagesize(szc);
432 if (pgsz <= PAGESIZE || !IS_P2ALIGNED(pgsz, pgsz)) {
433 panic("segvn_init: bad szc %d", szc);
434 /*NOTREACHED*/
435 }
436 szc--;
437 }
438 if (segvn_maxpgszc == 0 || segvn_maxpgszc > maxszc)
439 segvn_maxpgszc = maxszc;
440 }
441
442 if (segvn_maxpgszc) {
443 segvn_szc_cache = (struct kmem_cache **)kmem_alloc(
444 (segvn_maxpgszc + 1) * sizeof (struct kmem_cache *),
445 KM_SLEEP);
446 }
447
448 for (szc = 1; szc <= segvn_maxpgszc; szc++) {
449 char str[32];
450
451 (void) sprintf(str, "segvn_szc_cache%d", szc);
452 segvn_szc_cache[szc] = kmem_cache_create(str,
453 page_get_pagecnt(szc) * sizeof (page_t *), 0,
454 NULL, NULL, NULL, NULL, NULL, KMC_NODEBUG);
455 }
456
457
458 if (segvn_use_regions && !hat_supported(HAT_SHARED_REGIONS, NULL))
459 segvn_use_regions = 0;
460
461 /*
462 * For now shared regions and text replication segvn support
463 * are mutually exclusive. This is acceptable because
464 * currently significant benefit from text replication was
465 * only observed on AMD64 NUMA platforms (due to relatively
466 * small L2$ size) and currently we don't support shared
467 * regions on x86.
468 */
469 if (segvn_use_regions && !segvn_disable_textrepl) {
470 segvn_disable_textrepl = 1;
471 }
472
473 #if defined(_LP64)
474 if (lgrp_optimizations() && textrepl_size_thresh != (size_t)-1 &&
475 !segvn_disable_textrepl) {
476 ulong_t i;
477 size_t hsz = svntr_hashtab_sz * sizeof (svntr_bucket_t);
478
479 svntr_cache = kmem_cache_create("svntr_cache",
480 sizeof (svntr_t), 0, svntr_cache_constructor, NULL,
481 NULL, NULL, NULL, 0);
482 svntr_hashtab = kmem_zalloc(hsz, KM_SLEEP);
483 for (i = 0; i < svntr_hashtab_sz; i++) {
484 mutex_init(&svntr_hashtab[i].tr_lock, NULL,
485 MUTEX_DEFAULT, NULL);
486 }
487 segvn_textrepl_max_bytes = ptob(physmem) /
488 segvn_textrepl_max_bytes_factor;
489 segvn_textrepl_stats = kmem_zalloc(NCPU *
490 sizeof (svntr_stats_t), KM_SLEEP);
491 sema_init(&segvn_trasync_sem, 0, NULL, SEMA_DEFAULT, NULL);
492 (void) thread_create(NULL, 0, segvn_trasync_thread,
493 NULL, 0, &p0, TS_RUN, minclsyspri);
494 }
495 #endif
496
497 if (!ISP2(segvn_pglock_comb_balign) ||
498 segvn_pglock_comb_balign < PAGESIZE) {
499 segvn_pglock_comb_balign = 1UL << 16; /* 64K */
500 }
501 segvn_pglock_comb_bshift = highbit(segvn_pglock_comb_balign) - 1;
502 segvn_pglock_comb_palign = btop(segvn_pglock_comb_balign);
503 }
504
505 #define SEGVN_PAGEIO ((void *)0x1)
506 #define SEGVN_NOPAGEIO ((void *)0x2)
507
508 static void
segvn_setvnode_mpss(vnode_t * vp)509 segvn_setvnode_mpss(vnode_t *vp)
510 {
511 int err;
512
513 ASSERT(vp->v_mpssdata == NULL ||
514 vp->v_mpssdata == SEGVN_PAGEIO ||
515 vp->v_mpssdata == SEGVN_NOPAGEIO);
516
517 if (vp->v_mpssdata == NULL) {
518 if (vn_vmpss_usepageio(vp)) {
519 err = VOP_PAGEIO(vp, (page_t *)NULL,
520 (u_offset_t)0, 0, 0, CRED(), NULL);
521 } else {
522 err = ENOSYS;
523 }
524 /*
525 * set v_mpssdata just once per vnode life
526 * so that it never changes.
527 */
528 mutex_enter(&vp->v_lock);
529 if (vp->v_mpssdata == NULL) {
530 if (err == EINVAL) {
531 vp->v_mpssdata = SEGVN_PAGEIO;
532 } else {
533 vp->v_mpssdata = SEGVN_NOPAGEIO;
534 }
535 }
536 mutex_exit(&vp->v_lock);
537 }
538 }
539
540 int
segvn_create(struct seg * seg,void * argsp)541 segvn_create(struct seg *seg, void *argsp)
542 {
543 struct segvn_crargs *a = (struct segvn_crargs *)argsp;
544 struct segvn_data *svd;
545 size_t swresv = 0;
546 struct cred *cred;
547 struct anon_map *amp;
548 int error = 0;
549 size_t pgsz;
550 lgrp_mem_policy_t mpolicy = LGRP_MEM_POLICY_DEFAULT;
551 int use_rgn = 0;
552 int trok = 0;
553
554 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as));
555
556 if (a->type != MAP_PRIVATE && a->type != MAP_SHARED) {
557 panic("segvn_create type");
558 /*NOTREACHED*/
559 }
560
561 /*
562 * Check arguments. If a shared anon structure is given then
563 * it is illegal to also specify a vp.
564 */
565 if (a->amp != NULL && a->vp != NULL) {
566 panic("segvn_create anon_map");
567 /*NOTREACHED*/
568 }
569
570 if (a->type == MAP_PRIVATE && (a->flags & MAP_TEXT) &&
571 a->vp != NULL && a->prot == (PROT_USER | PROT_READ | PROT_EXEC) &&
572 segvn_use_regions) {
573 use_rgn = 1;
574 }
575
576 /* MAP_NORESERVE on a MAP_SHARED segment is meaningless. */
577 if (a->type == MAP_SHARED)
578 a->flags &= ~MAP_NORESERVE;
579
580 if (a->szc != 0) {
581 if (segvn_lpg_disable != 0 || (a->szc == AS_MAP_NO_LPOOB) ||
582 (a->amp != NULL && a->type == MAP_PRIVATE) ||
583 (a->flags & MAP_NORESERVE) || seg->s_as == &kas) {
584 a->szc = 0;
585 } else {
586 if (a->szc > segvn_maxpgszc)
587 a->szc = segvn_maxpgszc;
588 pgsz = page_get_pagesize(a->szc);
589 if (!IS_P2ALIGNED(seg->s_base, pgsz) ||
590 !IS_P2ALIGNED(seg->s_size, pgsz)) {
591 a->szc = 0;
592 } else if (a->vp != NULL) {
593 if (IS_SWAPFSVP(a->vp) || VN_ISKAS(a->vp)) {
594 /*
595 * paranoid check.
596 * hat_page_demote() is not supported
597 * on swapfs pages.
598 */
599 a->szc = 0;
600 } else if (map_addr_vacalign_check(seg->s_base,
601 a->offset & PAGEMASK)) {
602 a->szc = 0;
603 }
604 } else if (a->amp != NULL) {
605 pgcnt_t anum = btopr(a->offset);
606 pgcnt_t pgcnt = page_get_pagecnt(a->szc);
607 if (!IS_P2ALIGNED(anum, pgcnt)) {
608 a->szc = 0;
609 }
610 }
611 }
612 }
613
614 /*
615 * If segment may need private pages, reserve them now.
616 */
617 if (!(a->flags & MAP_NORESERVE) && ((a->vp == NULL && a->amp == NULL) ||
618 (a->type == MAP_PRIVATE && (a->prot & PROT_WRITE)))) {
619 if (anon_resv_zone(seg->s_size,
620 seg->s_as->a_proc->p_zone) == 0)
621 return (EAGAIN);
622 swresv = seg->s_size;
623 TRACE_3(TR_FAC_VM, TR_ANON_PROC, "anon proc:%p %lu %u",
624 seg, swresv, 1);
625 }
626
627 /*
628 * Reserve any mapping structures that may be required.
629 *
630 * Don't do it for segments that may use regions. It's currently a
631 * noop in the hat implementations anyway.
632 */
633 if (!use_rgn) {
634 hat_map(seg->s_as->a_hat, seg->s_base, seg->s_size, HAT_MAP);
635 }
636
637 if (a->cred) {
638 cred = a->cred;
639 crhold(cred);
640 } else {
641 crhold(cred = CRED());
642 }
643
644 /* Inform the vnode of the new mapping */
645 if (a->vp != NULL) {
646 error = VOP_ADDMAP(a->vp, a->offset & PAGEMASK,
647 seg->s_as, seg->s_base, seg->s_size, a->prot,
648 a->maxprot, a->type, cred, NULL);
649 if (error) {
650 if (swresv != 0) {
651 anon_unresv_zone(swresv,
652 seg->s_as->a_proc->p_zone);
653 TRACE_3(TR_FAC_VM, TR_ANON_PROC,
654 "anon proc:%p %lu %u", seg, swresv, 0);
655 }
656 crfree(cred);
657 if (!use_rgn) {
658 hat_unload(seg->s_as->a_hat, seg->s_base,
659 seg->s_size, HAT_UNLOAD_UNMAP);
660 }
661 return (error);
662 }
663 /*
664 * svntr_hashtab will be NULL if we support shared regions.
665 */
666 trok = ((a->flags & MAP_TEXT) &&
667 (seg->s_size > textrepl_size_thresh ||
668 (a->flags & _MAP_TEXTREPL)) &&
669 lgrp_optimizations() && svntr_hashtab != NULL &&
670 a->type == MAP_PRIVATE && swresv == 0 &&
671 !(a->flags & MAP_NORESERVE) &&
672 seg->s_as != &kas && a->vp->v_type == VREG);
673
674 ASSERT(!trok || !use_rgn);
675 }
676
677 /*
678 * MAP_NORESERVE mappings don't count towards the VSZ of a process
679 * until we fault the pages in.
680 */
681 if ((a->vp == NULL || a->vp->v_type != VREG) &&
682 a->flags & MAP_NORESERVE) {
683 seg->s_as->a_resvsize -= seg->s_size;
684 }
685
686 /*
687 * If more than one segment in the address space, and they're adjacent
688 * virtually, try to concatenate them. Don't concatenate if an
689 * explicit anon_map structure was supplied (e.g., SystemV shared
690 * memory) or if we'll use text replication for this segment.
691 */
692 if (a->amp == NULL && !use_rgn && !trok) {
693 struct seg *pseg, *nseg;
694 struct segvn_data *psvd, *nsvd;
695 lgrp_mem_policy_t ppolicy, npolicy;
696 uint_t lgrp_mem_policy_flags = 0;
697 extern lgrp_mem_policy_t lgrp_mem_default_policy;
698
699 /*
700 * Memory policy flags (lgrp_mem_policy_flags) is valid when
701 * extending stack/heap segments.
702 */
703 if ((a->vp == NULL) && (a->type == MAP_PRIVATE) &&
704 !(a->flags & MAP_NORESERVE) && (seg->s_as != &kas)) {
705 lgrp_mem_policy_flags = a->lgrp_mem_policy_flags;
706 } else {
707 /*
708 * Get policy when not extending it from another segment
709 */
710 mpolicy = lgrp_mem_policy_default(seg->s_size, a->type);
711 }
712
713 /*
714 * First, try to concatenate the previous and new segments
715 */
716 pseg = AS_SEGPREV(seg->s_as, seg);
717 if (pseg != NULL &&
718 pseg->s_base + pseg->s_size == seg->s_base &&
719 pseg->s_ops == &segvn_ops) {
720 /*
721 * Get memory allocation policy from previous segment.
722 * When extension is specified (e.g. for heap) apply
723 * this policy to the new segment regardless of the
724 * outcome of segment concatenation. Extension occurs
725 * for non-default policy otherwise default policy is
726 * used and is based on extended segment size.
727 */
728 psvd = (struct segvn_data *)pseg->s_data;
729 ppolicy = psvd->policy_info.mem_policy;
730 if (lgrp_mem_policy_flags ==
731 LGRP_MP_FLAG_EXTEND_UP) {
732 if (ppolicy != lgrp_mem_default_policy) {
733 mpolicy = ppolicy;
734 } else {
735 mpolicy = lgrp_mem_policy_default(
736 pseg->s_size + seg->s_size,
737 a->type);
738 }
739 }
740
741 if (mpolicy == ppolicy &&
742 (pseg->s_size + seg->s_size <=
743 segvn_comb_thrshld || psvd->amp == NULL) &&
744 segvn_extend_prev(pseg, seg, a, swresv) == 0) {
745 /*
746 * success! now try to concatenate
747 * with following seg
748 */
749 crfree(cred);
750 nseg = AS_SEGNEXT(pseg->s_as, pseg);
751 if (nseg != NULL &&
752 nseg != pseg &&
753 nseg->s_ops == &segvn_ops &&
754 pseg->s_base + pseg->s_size ==
755 nseg->s_base)
756 (void) segvn_concat(pseg, nseg, 0);
757 ASSERT(pseg->s_szc == 0 ||
758 (a->szc == pseg->s_szc &&
759 IS_P2ALIGNED(pseg->s_base, pgsz) &&
760 IS_P2ALIGNED(pseg->s_size, pgsz)));
761 return (0);
762 }
763 }
764
765 /*
766 * Failed, so try to concatenate with following seg
767 */
768 nseg = AS_SEGNEXT(seg->s_as, seg);
769 if (nseg != NULL &&
770 seg->s_base + seg->s_size == nseg->s_base &&
771 nseg->s_ops == &segvn_ops) {
772 /*
773 * Get memory allocation policy from next segment.
774 * When extension is specified (e.g. for stack) apply
775 * this policy to the new segment regardless of the
776 * outcome of segment concatenation. Extension occurs
777 * for non-default policy otherwise default policy is
778 * used and is based on extended segment size.
779 */
780 nsvd = (struct segvn_data *)nseg->s_data;
781 npolicy = nsvd->policy_info.mem_policy;
782 if (lgrp_mem_policy_flags ==
783 LGRP_MP_FLAG_EXTEND_DOWN) {
784 if (npolicy != lgrp_mem_default_policy) {
785 mpolicy = npolicy;
786 } else {
787 mpolicy = lgrp_mem_policy_default(
788 nseg->s_size + seg->s_size,
789 a->type);
790 }
791 }
792
793 if (mpolicy == npolicy &&
794 segvn_extend_next(seg, nseg, a, swresv) == 0) {
795 crfree(cred);
796 ASSERT(nseg->s_szc == 0 ||
797 (a->szc == nseg->s_szc &&
798 IS_P2ALIGNED(nseg->s_base, pgsz) &&
799 IS_P2ALIGNED(nseg->s_size, pgsz)));
800 return (0);
801 }
802 }
803 }
804
805 if (a->vp != NULL) {
806 VN_HOLD(a->vp);
807 if (a->type == MAP_SHARED)
808 lgrp_shm_policy_init(NULL, a->vp);
809 }
810 svd = kmem_cache_alloc(segvn_cache, KM_SLEEP);
811
812 seg->s_ops = &segvn_ops;
813 seg->s_data = (void *)svd;
814 seg->s_szc = a->szc;
815
816 svd->seg = seg;
817 svd->vp = a->vp;
818 /*
819 * Anonymous mappings have no backing file so the offset is meaningless.
820 */
821 svd->offset = a->vp ? (a->offset & PAGEMASK) : 0;
822 svd->prot = a->prot;
823 svd->maxprot = a->maxprot;
824 svd->pageprot = 0;
825 svd->type = a->type;
826 svd->vpage = NULL;
827 svd->cred = cred;
828 svd->advice = MADV_NORMAL;
829 svd->pageadvice = 0;
830 svd->flags = (ushort_t)a->flags;
831 svd->softlockcnt = 0;
832 svd->softlockcnt_sbase = 0;
833 svd->softlockcnt_send = 0;
834 svd->svn_inz = 0;
835 svd->rcookie = HAT_INVALID_REGION_COOKIE;
836 svd->pageswap = 0;
837
838 if (a->szc != 0 && a->vp != NULL) {
839 segvn_setvnode_mpss(a->vp);
840 }
841 if (svd->type == MAP_SHARED && svd->vp != NULL &&
842 (svd->vp->v_flag & VVMEXEC) && (svd->prot & PROT_WRITE)) {
843 ASSERT(vn_is_mapped(svd->vp, V_WRITE));
844 segvn_inval_trcache(svd->vp);
845 }
846
847 amp = a->amp;
848 if ((svd->amp = amp) == NULL) {
849 svd->anon_index = 0;
850 if (svd->type == MAP_SHARED) {
851 svd->swresv = 0;
852 /*
853 * Shared mappings to a vp need no other setup.
854 * If we have a shared mapping to an anon_map object
855 * which hasn't been allocated yet, allocate the
856 * struct now so that it will be properly shared
857 * by remembering the swap reservation there.
858 */
859 if (a->vp == NULL) {
860 svd->amp = anonmap_alloc(seg->s_size, swresv,
861 ANON_SLEEP);
862 svd->amp->a_szc = seg->s_szc;
863 }
864 } else {
865 /*
866 * Private mapping (with or without a vp).
867 * Allocate anon_map when needed.
868 */
869 svd->swresv = swresv;
870 }
871 } else {
872 pgcnt_t anon_num;
873
874 /*
875 * Mapping to an existing anon_map structure without a vp.
876 * For now we will insure that the segment size isn't larger
877 * than the size - offset gives us. Later on we may wish to
878 * have the anon array dynamically allocated itself so that
879 * we don't always have to allocate all the anon pointer slots.
880 * This of course involves adding extra code to check that we
881 * aren't trying to use an anon pointer slot beyond the end
882 * of the currently allocated anon array.
883 */
884 if ((amp->size - a->offset) < seg->s_size) {
885 panic("segvn_create anon_map size");
886 /*NOTREACHED*/
887 }
888
889 anon_num = btopr(a->offset);
890
891 if (a->type == MAP_SHARED) {
892 /*
893 * SHARED mapping to a given anon_map.
894 */
895 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
896 amp->refcnt++;
897 if (a->szc > amp->a_szc) {
898 amp->a_szc = a->szc;
899 }
900 ANON_LOCK_EXIT(&->a_rwlock);
901 svd->anon_index = anon_num;
902 svd->swresv = 0;
903 } else {
904 /*
905 * PRIVATE mapping to a given anon_map.
906 * Make sure that all the needed anon
907 * structures are created (so that we will
908 * share the underlying pages if nothing
909 * is written by this mapping) and then
910 * duplicate the anon array as is done
911 * when a privately mapped segment is dup'ed.
912 */
913 struct anon *ap;
914 caddr_t addr;
915 caddr_t eaddr;
916 ulong_t anon_idx;
917 int hat_flag = HAT_LOAD;
918
919 if (svd->flags & MAP_TEXT) {
920 hat_flag |= HAT_LOAD_TEXT;
921 }
922
923 svd->amp = anonmap_alloc(seg->s_size, 0, ANON_SLEEP);
924 svd->amp->a_szc = seg->s_szc;
925 svd->anon_index = 0;
926 svd->swresv = swresv;
927
928 /*
929 * Prevent 2 threads from allocating anon
930 * slots simultaneously.
931 */
932 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
933 eaddr = seg->s_base + seg->s_size;
934
935 for (anon_idx = anon_num, addr = seg->s_base;
936 addr < eaddr; addr += PAGESIZE, anon_idx++) {
937 page_t *pp;
938
939 if ((ap = anon_get_ptr(amp->ahp,
940 anon_idx)) != NULL)
941 continue;
942
943 /*
944 * Allocate the anon struct now.
945 * Might as well load up translation
946 * to the page while we're at it...
947 */
948 pp = anon_zero(seg, addr, &ap, cred);
949 if (ap == NULL || pp == NULL) {
950 panic("segvn_create anon_zero");
951 /*NOTREACHED*/
952 }
953
954 /*
955 * Re-acquire the anon_map lock and
956 * initialize the anon array entry.
957 */
958 ASSERT(anon_get_ptr(amp->ahp,
959 anon_idx) == NULL);
960 (void) anon_set_ptr(amp->ahp, anon_idx, ap,
961 ANON_SLEEP);
962
963 ASSERT(seg->s_szc == 0);
964 ASSERT(!IS_VMODSORT(pp->p_vnode));
965
966 ASSERT(use_rgn == 0);
967 hat_memload(seg->s_as->a_hat, addr, pp,
968 svd->prot & ~PROT_WRITE, hat_flag);
969
970 page_unlock(pp);
971 }
972 ASSERT(seg->s_szc == 0);
973 anon_dup(amp->ahp, anon_num, svd->amp->ahp,
974 0, seg->s_size);
975 ANON_LOCK_EXIT(&->a_rwlock);
976 }
977 }
978
979 /*
980 * Set default memory allocation policy for segment
981 *
982 * Always set policy for private memory at least for initialization
983 * even if this is a shared memory segment
984 */
985 (void) lgrp_privm_policy_set(mpolicy, &svd->policy_info, seg->s_size);
986
987 if (svd->type == MAP_SHARED)
988 (void) lgrp_shm_policy_set(mpolicy, svd->amp, svd->anon_index,
989 svd->vp, svd->offset, seg->s_size);
990
991 if (use_rgn) {
992 ASSERT(!trok);
993 ASSERT(svd->amp == NULL);
994 svd->rcookie = hat_join_region(seg->s_as->a_hat, seg->s_base,
995 seg->s_size, (void *)svd->vp, svd->offset, svd->prot,
996 (uchar_t)seg->s_szc, segvn_hat_rgn_unload_callback,
997 HAT_REGION_TEXT);
998 }
999
1000 ASSERT(!trok || !(svd->prot & PROT_WRITE));
1001 svd->tr_state = trok ? SEGVN_TR_INIT : SEGVN_TR_OFF;
1002
1003 return (0);
1004 }
1005
1006 /*
1007 * Concatenate two existing segments, if possible.
1008 * Return 0 on success, -1 if two segments are not compatible
1009 * or -2 on memory allocation failure.
1010 * If amp_cat == 1 then try and concat segments with anon maps
1011 */
1012 static int
segvn_concat(struct seg * seg1,struct seg * seg2,int amp_cat)1013 segvn_concat(struct seg *seg1, struct seg *seg2, int amp_cat)
1014 {
1015 struct segvn_data *svd1 = seg1->s_data;
1016 struct segvn_data *svd2 = seg2->s_data;
1017 struct anon_map *amp1 = svd1->amp;
1018 struct anon_map *amp2 = svd2->amp;
1019 struct vpage *vpage1 = svd1->vpage;
1020 struct vpage *vpage2 = svd2->vpage, *nvpage = NULL;
1021 size_t size, nvpsize;
1022 pgcnt_t npages1, npages2;
1023
1024 ASSERT(seg1->s_as && seg2->s_as && seg1->s_as == seg2->s_as);
1025 ASSERT(AS_WRITE_HELD(seg1->s_as));
1026 ASSERT(seg1->s_ops == seg2->s_ops);
1027
1028 if (HAT_IS_REGION_COOKIE_VALID(svd1->rcookie) ||
1029 HAT_IS_REGION_COOKIE_VALID(svd2->rcookie)) {
1030 return (-1);
1031 }
1032
1033 /* both segments exist, try to merge them */
1034 #define incompat(x) (svd1->x != svd2->x)
1035 if (incompat(vp) || incompat(maxprot) ||
1036 (!svd1->pageadvice && !svd2->pageadvice && incompat(advice)) ||
1037 (!svd1->pageprot && !svd2->pageprot && incompat(prot)) ||
1038 incompat(type) || incompat(cred) || incompat(flags) ||
1039 seg1->s_szc != seg2->s_szc || incompat(policy_info.mem_policy) ||
1040 (svd2->softlockcnt > 0) || svd1->softlockcnt_send > 0)
1041 return (-1);
1042 #undef incompat
1043
1044 /*
1045 * vp == NULL implies zfod, offset doesn't matter
1046 */
1047 if (svd1->vp != NULL &&
1048 svd1->offset + seg1->s_size != svd2->offset) {
1049 return (-1);
1050 }
1051
1052 /*
1053 * Don't concatenate if either segment uses text replication.
1054 */
1055 if (svd1->tr_state != SEGVN_TR_OFF || svd2->tr_state != SEGVN_TR_OFF) {
1056 return (-1);
1057 }
1058
1059 /*
1060 * Fail early if we're not supposed to concatenate
1061 * segments with non NULL amp.
1062 */
1063 if (amp_cat == 0 && (amp1 != NULL || amp2 != NULL)) {
1064 return (-1);
1065 }
1066
1067 if (svd1->vp == NULL && svd1->type == MAP_SHARED) {
1068 if (amp1 != amp2) {
1069 return (-1);
1070 }
1071 if (amp1 != NULL && svd1->anon_index + btop(seg1->s_size) !=
1072 svd2->anon_index) {
1073 return (-1);
1074 }
1075 ASSERT(amp1 == NULL || amp1->refcnt >= 2);
1076 }
1077
1078 /*
1079 * If either seg has vpages, create a new merged vpage array.
1080 */
1081 if (vpage1 != NULL || vpage2 != NULL) {
1082 struct vpage *vp, *evp;
1083
1084 npages1 = seg_pages(seg1);
1085 npages2 = seg_pages(seg2);
1086 nvpsize = vpgtob(npages1 + npages2);
1087
1088 if ((nvpage = kmem_zalloc(nvpsize, KM_NOSLEEP)) == NULL) {
1089 return (-2);
1090 }
1091
1092 if (vpage1 != NULL) {
1093 bcopy(vpage1, nvpage, vpgtob(npages1));
1094 } else {
1095 evp = nvpage + npages1;
1096 for (vp = nvpage; vp < evp; vp++) {
1097 VPP_SETPROT(vp, svd1->prot);
1098 VPP_SETADVICE(vp, svd1->advice);
1099 }
1100 }
1101
1102 if (vpage2 != NULL) {
1103 bcopy(vpage2, nvpage + npages1, vpgtob(npages2));
1104 } else {
1105 evp = nvpage + npages1 + npages2;
1106 for (vp = nvpage + npages1; vp < evp; vp++) {
1107 VPP_SETPROT(vp, svd2->prot);
1108 VPP_SETADVICE(vp, svd2->advice);
1109 }
1110 }
1111
1112 if (svd2->pageswap && (!svd1->pageswap && svd1->swresv)) {
1113 ASSERT(svd1->swresv == seg1->s_size);
1114 ASSERT(!(svd1->flags & MAP_NORESERVE));
1115 ASSERT(!(svd2->flags & MAP_NORESERVE));
1116 evp = nvpage + npages1;
1117 for (vp = nvpage; vp < evp; vp++) {
1118 VPP_SETSWAPRES(vp);
1119 }
1120 }
1121
1122 if (svd1->pageswap && (!svd2->pageswap && svd2->swresv)) {
1123 ASSERT(svd2->swresv == seg2->s_size);
1124 ASSERT(!(svd1->flags & MAP_NORESERVE));
1125 ASSERT(!(svd2->flags & MAP_NORESERVE));
1126 vp = nvpage + npages1;
1127 evp = vp + npages2;
1128 for (; vp < evp; vp++) {
1129 VPP_SETSWAPRES(vp);
1130 }
1131 }
1132 }
1133 ASSERT((vpage1 != NULL || vpage2 != NULL) ||
1134 (svd1->pageswap == 0 && svd2->pageswap == 0));
1135
1136 /*
1137 * If either segment has private pages, create a new merged anon
1138 * array. If mergeing shared anon segments just decrement anon map's
1139 * refcnt.
1140 */
1141 if (amp1 != NULL && svd1->type == MAP_SHARED) {
1142 ASSERT(amp1 == amp2 && svd1->vp == NULL);
1143 ANON_LOCK_ENTER(&1->a_rwlock, RW_WRITER);
1144 ASSERT(amp1->refcnt >= 2);
1145 amp1->refcnt--;
1146 ANON_LOCK_EXIT(&1->a_rwlock);
1147 svd2->amp = NULL;
1148 } else if (amp1 != NULL || amp2 != NULL) {
1149 struct anon_hdr *nahp;
1150 struct anon_map *namp = NULL;
1151 size_t asize;
1152
1153 ASSERT(svd1->type == MAP_PRIVATE);
1154
1155 asize = seg1->s_size + seg2->s_size;
1156 if ((nahp = anon_create(btop(asize), ANON_NOSLEEP)) == NULL) {
1157 if (nvpage != NULL) {
1158 kmem_free(nvpage, nvpsize);
1159 }
1160 return (-2);
1161 }
1162 if (amp1 != NULL) {
1163 /*
1164 * XXX anon rwlock is not really needed because
1165 * this is a private segment and we are writers.
1166 */
1167 ANON_LOCK_ENTER(&1->a_rwlock, RW_WRITER);
1168 ASSERT(amp1->refcnt == 1);
1169 if (anon_copy_ptr(amp1->ahp, svd1->anon_index,
1170 nahp, 0, btop(seg1->s_size), ANON_NOSLEEP)) {
1171 anon_release(nahp, btop(asize));
1172 ANON_LOCK_EXIT(&1->a_rwlock);
1173 if (nvpage != NULL) {
1174 kmem_free(nvpage, nvpsize);
1175 }
1176 return (-2);
1177 }
1178 }
1179 if (amp2 != NULL) {
1180 ANON_LOCK_ENTER(&2->a_rwlock, RW_WRITER);
1181 ASSERT(amp2->refcnt == 1);
1182 if (anon_copy_ptr(amp2->ahp, svd2->anon_index,
1183 nahp, btop(seg1->s_size), btop(seg2->s_size),
1184 ANON_NOSLEEP)) {
1185 anon_release(nahp, btop(asize));
1186 ANON_LOCK_EXIT(&2->a_rwlock);
1187 if (amp1 != NULL) {
1188 ANON_LOCK_EXIT(&1->a_rwlock);
1189 }
1190 if (nvpage != NULL) {
1191 kmem_free(nvpage, nvpsize);
1192 }
1193 return (-2);
1194 }
1195 }
1196 if (amp1 != NULL) {
1197 namp = amp1;
1198 anon_release(amp1->ahp, btop(amp1->size));
1199 }
1200 if (amp2 != NULL) {
1201 if (namp == NULL) {
1202 ASSERT(amp1 == NULL);
1203 namp = amp2;
1204 anon_release(amp2->ahp, btop(amp2->size));
1205 } else {
1206 amp2->refcnt--;
1207 ANON_LOCK_EXIT(&2->a_rwlock);
1208 anonmap_free(amp2);
1209 }
1210 svd2->amp = NULL; /* needed for seg_free */
1211 }
1212 namp->ahp = nahp;
1213 namp->size = asize;
1214 svd1->amp = namp;
1215 svd1->anon_index = 0;
1216 ANON_LOCK_EXIT(&namp->a_rwlock);
1217 }
1218 /*
1219 * Now free the old vpage structures.
1220 */
1221 if (nvpage != NULL) {
1222 if (vpage1 != NULL) {
1223 kmem_free(vpage1, vpgtob(npages1));
1224 }
1225 if (vpage2 != NULL) {
1226 svd2->vpage = NULL;
1227 kmem_free(vpage2, vpgtob(npages2));
1228 }
1229 if (svd2->pageprot) {
1230 svd1->pageprot = 1;
1231 }
1232 if (svd2->pageadvice) {
1233 svd1->pageadvice = 1;
1234 }
1235 if (svd2->pageswap) {
1236 svd1->pageswap = 1;
1237 }
1238 svd1->vpage = nvpage;
1239 }
1240
1241 /* all looks ok, merge segments */
1242 svd1->swresv += svd2->swresv;
1243 svd2->swresv = 0; /* so seg_free doesn't release swap space */
1244 size = seg2->s_size;
1245 seg_free(seg2);
1246 seg1->s_size += size;
1247 return (0);
1248 }
1249
1250 /*
1251 * Extend the previous segment (seg1) to include the
1252 * new segment (seg2 + a), if possible.
1253 * Return 0 on success.
1254 */
1255 static int
segvn_extend_prev(seg1,seg2,a,swresv)1256 segvn_extend_prev(seg1, seg2, a, swresv)
1257 struct seg *seg1, *seg2;
1258 struct segvn_crargs *a;
1259 size_t swresv;
1260 {
1261 struct segvn_data *svd1 = (struct segvn_data *)seg1->s_data;
1262 size_t size;
1263 struct anon_map *amp1;
1264 struct vpage *new_vpage;
1265
1266 /*
1267 * We don't need any segment level locks for "segvn" data
1268 * since the address space is "write" locked.
1269 */
1270 ASSERT(seg1->s_as && AS_WRITE_HELD(seg1->s_as));
1271
1272 if (HAT_IS_REGION_COOKIE_VALID(svd1->rcookie)) {
1273 return (-1);
1274 }
1275
1276 /* second segment is new, try to extend first */
1277 /* XXX - should also check cred */
1278 if (svd1->vp != a->vp || svd1->maxprot != a->maxprot ||
1279 (!svd1->pageprot && (svd1->prot != a->prot)) ||
1280 svd1->type != a->type || svd1->flags != a->flags ||
1281 seg1->s_szc != a->szc || svd1->softlockcnt_send > 0)
1282 return (-1);
1283
1284 /* vp == NULL implies zfod, offset doesn't matter */
1285 if (svd1->vp != NULL &&
1286 svd1->offset + seg1->s_size != (a->offset & PAGEMASK))
1287 return (-1);
1288
1289 if (svd1->tr_state != SEGVN_TR_OFF) {
1290 return (-1);
1291 }
1292
1293 amp1 = svd1->amp;
1294 if (amp1) {
1295 pgcnt_t newpgs;
1296
1297 /*
1298 * Segment has private pages, can data structures
1299 * be expanded?
1300 *
1301 * Acquire the anon_map lock to prevent it from changing,
1302 * if it is shared. This ensures that the anon_map
1303 * will not change while a thread which has a read/write
1304 * lock on an address space references it.
1305 * XXX - Don't need the anon_map lock at all if "refcnt"
1306 * is 1.
1307 *
1308 * Can't grow a MAP_SHARED segment with an anonmap because
1309 * there may be existing anon slots where we want to extend
1310 * the segment and we wouldn't know what to do with them
1311 * (e.g., for tmpfs right thing is to just leave them there,
1312 * for /dev/zero they should be cleared out).
1313 */
1314 if (svd1->type == MAP_SHARED)
1315 return (-1);
1316
1317 ANON_LOCK_ENTER(&1->a_rwlock, RW_WRITER);
1318 if (amp1->refcnt > 1) {
1319 ANON_LOCK_EXIT(&1->a_rwlock);
1320 return (-1);
1321 }
1322 newpgs = anon_grow(amp1->ahp, &svd1->anon_index,
1323 btop(seg1->s_size), btop(seg2->s_size), ANON_NOSLEEP);
1324
1325 if (newpgs == 0) {
1326 ANON_LOCK_EXIT(&1->a_rwlock);
1327 return (-1);
1328 }
1329 amp1->size = ptob(newpgs);
1330 ANON_LOCK_EXIT(&1->a_rwlock);
1331 }
1332 if (svd1->vpage != NULL) {
1333 struct vpage *vp, *evp;
1334 new_vpage =
1335 kmem_zalloc(vpgtob(seg_pages(seg1) + seg_pages(seg2)),
1336 KM_NOSLEEP);
1337 if (new_vpage == NULL)
1338 return (-1);
1339 bcopy(svd1->vpage, new_vpage, vpgtob(seg_pages(seg1)));
1340 kmem_free(svd1->vpage, vpgtob(seg_pages(seg1)));
1341 svd1->vpage = new_vpage;
1342
1343 vp = new_vpage + seg_pages(seg1);
1344 evp = vp + seg_pages(seg2);
1345 for (; vp < evp; vp++)
1346 VPP_SETPROT(vp, a->prot);
1347 if (svd1->pageswap && swresv) {
1348 ASSERT(!(svd1->flags & MAP_NORESERVE));
1349 ASSERT(swresv == seg2->s_size);
1350 vp = new_vpage + seg_pages(seg1);
1351 for (; vp < evp; vp++) {
1352 VPP_SETSWAPRES(vp);
1353 }
1354 }
1355 }
1356 ASSERT(svd1->vpage != NULL || svd1->pageswap == 0);
1357 size = seg2->s_size;
1358 seg_free(seg2);
1359 seg1->s_size += size;
1360 svd1->swresv += swresv;
1361 if (svd1->pageprot && (a->prot & PROT_WRITE) &&
1362 svd1->type == MAP_SHARED && svd1->vp != NULL &&
1363 (svd1->vp->v_flag & VVMEXEC)) {
1364 ASSERT(vn_is_mapped(svd1->vp, V_WRITE));
1365 segvn_inval_trcache(svd1->vp);
1366 }
1367 return (0);
1368 }
1369
1370 /*
1371 * Extend the next segment (seg2) to include the
1372 * new segment (seg1 + a), if possible.
1373 * Return 0 on success.
1374 */
1375 static int
segvn_extend_next(struct seg * seg1,struct seg * seg2,struct segvn_crargs * a,size_t swresv)1376 segvn_extend_next(
1377 struct seg *seg1,
1378 struct seg *seg2,
1379 struct segvn_crargs *a,
1380 size_t swresv)
1381 {
1382 struct segvn_data *svd2 = (struct segvn_data *)seg2->s_data;
1383 size_t size;
1384 struct anon_map *amp2;
1385 struct vpage *new_vpage;
1386
1387 /*
1388 * We don't need any segment level locks for "segvn" data
1389 * since the address space is "write" locked.
1390 */
1391 ASSERT(seg2->s_as && AS_WRITE_HELD(seg2->s_as));
1392
1393 if (HAT_IS_REGION_COOKIE_VALID(svd2->rcookie)) {
1394 return (-1);
1395 }
1396
1397 /* first segment is new, try to extend second */
1398 /* XXX - should also check cred */
1399 if (svd2->vp != a->vp || svd2->maxprot != a->maxprot ||
1400 (!svd2->pageprot && (svd2->prot != a->prot)) ||
1401 svd2->type != a->type || svd2->flags != a->flags ||
1402 seg2->s_szc != a->szc || svd2->softlockcnt_sbase > 0)
1403 return (-1);
1404 /* vp == NULL implies zfod, offset doesn't matter */
1405 if (svd2->vp != NULL &&
1406 (a->offset & PAGEMASK) + seg1->s_size != svd2->offset)
1407 return (-1);
1408
1409 if (svd2->tr_state != SEGVN_TR_OFF) {
1410 return (-1);
1411 }
1412
1413 amp2 = svd2->amp;
1414 if (amp2) {
1415 pgcnt_t newpgs;
1416
1417 /*
1418 * Segment has private pages, can data structures
1419 * be expanded?
1420 *
1421 * Acquire the anon_map lock to prevent it from changing,
1422 * if it is shared. This ensures that the anon_map
1423 * will not change while a thread which has a read/write
1424 * lock on an address space references it.
1425 *
1426 * XXX - Don't need the anon_map lock at all if "refcnt"
1427 * is 1.
1428 */
1429 if (svd2->type == MAP_SHARED)
1430 return (-1);
1431
1432 ANON_LOCK_ENTER(&2->a_rwlock, RW_WRITER);
1433 if (amp2->refcnt > 1) {
1434 ANON_LOCK_EXIT(&2->a_rwlock);
1435 return (-1);
1436 }
1437 newpgs = anon_grow(amp2->ahp, &svd2->anon_index,
1438 btop(seg2->s_size), btop(seg1->s_size),
1439 ANON_NOSLEEP | ANON_GROWDOWN);
1440
1441 if (newpgs == 0) {
1442 ANON_LOCK_EXIT(&2->a_rwlock);
1443 return (-1);
1444 }
1445 amp2->size = ptob(newpgs);
1446 ANON_LOCK_EXIT(&2->a_rwlock);
1447 }
1448 if (svd2->vpage != NULL) {
1449 struct vpage *vp, *evp;
1450 new_vpage =
1451 kmem_zalloc(vpgtob(seg_pages(seg1) + seg_pages(seg2)),
1452 KM_NOSLEEP);
1453 if (new_vpage == NULL) {
1454 /* Not merging segments so adjust anon_index back */
1455 if (amp2)
1456 svd2->anon_index += seg_pages(seg1);
1457 return (-1);
1458 }
1459 bcopy(svd2->vpage, new_vpage + seg_pages(seg1),
1460 vpgtob(seg_pages(seg2)));
1461 kmem_free(svd2->vpage, vpgtob(seg_pages(seg2)));
1462 svd2->vpage = new_vpage;
1463
1464 vp = new_vpage;
1465 evp = vp + seg_pages(seg1);
1466 for (; vp < evp; vp++)
1467 VPP_SETPROT(vp, a->prot);
1468 if (svd2->pageswap && swresv) {
1469 ASSERT(!(svd2->flags & MAP_NORESERVE));
1470 ASSERT(swresv == seg1->s_size);
1471 vp = new_vpage;
1472 for (; vp < evp; vp++) {
1473 VPP_SETSWAPRES(vp);
1474 }
1475 }
1476 }
1477 ASSERT(svd2->vpage != NULL || svd2->pageswap == 0);
1478 size = seg1->s_size;
1479 seg_free(seg1);
1480 seg2->s_size += size;
1481 seg2->s_base -= size;
1482 svd2->offset -= size;
1483 svd2->swresv += swresv;
1484 if (svd2->pageprot && (a->prot & PROT_WRITE) &&
1485 svd2->type == MAP_SHARED && svd2->vp != NULL &&
1486 (svd2->vp->v_flag & VVMEXEC)) {
1487 ASSERT(vn_is_mapped(svd2->vp, V_WRITE));
1488 segvn_inval_trcache(svd2->vp);
1489 }
1490 return (0);
1491 }
1492
1493 /*
1494 * Duplicate all the pages in the segment. This may break COW sharing for a
1495 * given page. If the page is marked with inherit zero set, then instead of
1496 * duplicating the page, we zero the page.
1497 */
1498 static int
segvn_dup_pages(struct seg * seg,struct seg * newseg)1499 segvn_dup_pages(struct seg *seg, struct seg *newseg)
1500 {
1501 int error;
1502 uint_t prot;
1503 page_t *pp;
1504 struct anon *ap, *newap;
1505 size_t i;
1506 caddr_t addr;
1507
1508 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
1509 struct segvn_data *newsvd = (struct segvn_data *)newseg->s_data;
1510 ulong_t old_idx = svd->anon_index;
1511 ulong_t new_idx = 0;
1512
1513 i = btopr(seg->s_size);
1514 addr = seg->s_base;
1515
1516 /*
1517 * XXX break cow sharing using PAGESIZE
1518 * pages. They will be relocated into larger
1519 * pages at fault time.
1520 */
1521 while (i-- > 0) {
1522 if ((ap = anon_get_ptr(svd->amp->ahp, old_idx)) != NULL) {
1523 struct vpage *vpp;
1524
1525 vpp = &svd->vpage[seg_page(seg, addr)];
1526
1527 /*
1528 * prot need not be computed below 'cause anon_private
1529 * is going to ignore it anyway as child doesn't inherit
1530 * pagelock from parent.
1531 */
1532 prot = svd->pageprot ? VPP_PROT(vpp) : svd->prot;
1533
1534 /*
1535 * Check whether we should zero this or dup it.
1536 */
1537 if (svd->svn_inz == SEGVN_INZ_ALL ||
1538 (svd->svn_inz == SEGVN_INZ_VPP &&
1539 VPP_ISINHZERO(vpp))) {
1540 pp = anon_zero(newseg, addr, &newap,
1541 newsvd->cred);
1542 } else {
1543 page_t *anon_pl[1+1];
1544 uint_t vpprot;
1545 error = anon_getpage(&ap, &vpprot, anon_pl,
1546 PAGESIZE, seg, addr, S_READ, svd->cred);
1547 if (error != 0)
1548 return (error);
1549
1550 pp = anon_private(&newap, newseg, addr, prot,
1551 anon_pl[0], 0, newsvd->cred);
1552 }
1553 if (pp == NULL) {
1554 return (ENOMEM);
1555 }
1556 (void) anon_set_ptr(newsvd->amp->ahp, new_idx, newap,
1557 ANON_SLEEP);
1558 page_unlock(pp);
1559 }
1560 addr += PAGESIZE;
1561 old_idx++;
1562 new_idx++;
1563 }
1564
1565 return (0);
1566 }
1567
1568 static int
segvn_dup(struct seg * seg,struct seg * newseg)1569 segvn_dup(struct seg *seg, struct seg *newseg)
1570 {
1571 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
1572 struct segvn_data *newsvd;
1573 pgcnt_t npages = seg_pages(seg);
1574 int error = 0;
1575 size_t len;
1576 struct anon_map *amp;
1577
1578 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as));
1579 ASSERT(newseg->s_as->a_proc->p_parent == curproc);
1580
1581 /*
1582 * If segment has anon reserved, reserve more for the new seg.
1583 * For a MAP_NORESERVE segment swresv will be a count of all the
1584 * allocated anon slots; thus we reserve for the child as many slots
1585 * as the parent has allocated. This semantic prevents the child or
1586 * parent from dieing during a copy-on-write fault caused by trying
1587 * to write a shared pre-existing anon page.
1588 */
1589 if ((len = svd->swresv) != 0) {
1590 if (anon_resv(svd->swresv) == 0)
1591 return (ENOMEM);
1592
1593 TRACE_3(TR_FAC_VM, TR_ANON_PROC, "anon proc:%p %lu %u",
1594 seg, len, 0);
1595 }
1596
1597 newsvd = kmem_cache_alloc(segvn_cache, KM_SLEEP);
1598
1599 newseg->s_ops = &segvn_ops;
1600 newseg->s_data = (void *)newsvd;
1601 newseg->s_szc = seg->s_szc;
1602
1603 newsvd->seg = newseg;
1604 if ((newsvd->vp = svd->vp) != NULL) {
1605 VN_HOLD(svd->vp);
1606 if (svd->type == MAP_SHARED)
1607 lgrp_shm_policy_init(NULL, svd->vp);
1608 }
1609 newsvd->offset = svd->offset;
1610 newsvd->prot = svd->prot;
1611 newsvd->maxprot = svd->maxprot;
1612 newsvd->pageprot = svd->pageprot;
1613 newsvd->type = svd->type;
1614 newsvd->cred = svd->cred;
1615 crhold(newsvd->cred);
1616 newsvd->advice = svd->advice;
1617 newsvd->pageadvice = svd->pageadvice;
1618 newsvd->svn_inz = svd->svn_inz;
1619 newsvd->swresv = svd->swresv;
1620 newsvd->pageswap = svd->pageswap;
1621 newsvd->flags = svd->flags;
1622 newsvd->softlockcnt = 0;
1623 newsvd->softlockcnt_sbase = 0;
1624 newsvd->softlockcnt_send = 0;
1625 newsvd->policy_info = svd->policy_info;
1626 newsvd->rcookie = HAT_INVALID_REGION_COOKIE;
1627
1628 if ((amp = svd->amp) == NULL || svd->tr_state == SEGVN_TR_ON) {
1629 /*
1630 * Not attaching to a shared anon object.
1631 */
1632 ASSERT(!HAT_IS_REGION_COOKIE_VALID(svd->rcookie) ||
1633 svd->tr_state == SEGVN_TR_OFF);
1634 if (svd->tr_state == SEGVN_TR_ON) {
1635 ASSERT(newsvd->vp != NULL && amp != NULL);
1636 newsvd->tr_state = SEGVN_TR_INIT;
1637 } else {
1638 newsvd->tr_state = svd->tr_state;
1639 }
1640 newsvd->amp = NULL;
1641 newsvd->anon_index = 0;
1642 } else {
1643 /* regions for now are only used on pure vnode segments */
1644 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
1645 ASSERT(svd->tr_state == SEGVN_TR_OFF);
1646 newsvd->tr_state = SEGVN_TR_OFF;
1647 if (svd->type == MAP_SHARED) {
1648 ASSERT(svd->svn_inz == SEGVN_INZ_NONE);
1649 newsvd->amp = amp;
1650 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
1651 amp->refcnt++;
1652 ANON_LOCK_EXIT(&->a_rwlock);
1653 newsvd->anon_index = svd->anon_index;
1654 } else {
1655 int reclaim = 1;
1656
1657 /*
1658 * Allocate and initialize new anon_map structure.
1659 */
1660 newsvd->amp = anonmap_alloc(newseg->s_size, 0,
1661 ANON_SLEEP);
1662 newsvd->amp->a_szc = newseg->s_szc;
1663 newsvd->anon_index = 0;
1664 ASSERT(svd->svn_inz == SEGVN_INZ_NONE ||
1665 svd->svn_inz == SEGVN_INZ_ALL ||
1666 svd->svn_inz == SEGVN_INZ_VPP);
1667
1668 /*
1669 * We don't have to acquire the anon_map lock
1670 * for the new segment (since it belongs to an
1671 * address space that is still not associated
1672 * with any process), or the segment in the old
1673 * address space (since all threads in it
1674 * are stopped while duplicating the address space).
1675 */
1676
1677 /*
1678 * The goal of the following code is to make sure that
1679 * softlocked pages do not end up as copy on write
1680 * pages. This would cause problems where one
1681 * thread writes to a page that is COW and a different
1682 * thread in the same process has softlocked it. The
1683 * softlock lock would move away from this process
1684 * because the write would cause this process to get
1685 * a copy (without the softlock).
1686 *
1687 * The strategy here is to just break the
1688 * sharing on pages that could possibly be
1689 * softlocked.
1690 *
1691 * In addition, if any pages have been marked that they
1692 * should be inherited as zero, then we immediately go
1693 * ahead and break COW and zero them. In the case of a
1694 * softlocked page that should be inherited zero, we
1695 * break COW and just get a zero page.
1696 */
1697 retry:
1698 if (svd->softlockcnt ||
1699 svd->svn_inz != SEGVN_INZ_NONE) {
1700 /*
1701 * The softlock count might be non zero
1702 * because some pages are still stuck in the
1703 * cache for lazy reclaim. Flush the cache
1704 * now. This should drop the count to zero.
1705 * [or there is really I/O going on to these
1706 * pages]. Note, we have the writers lock so
1707 * nothing gets inserted during the flush.
1708 */
1709 if (svd->softlockcnt && reclaim == 1) {
1710 segvn_purge(seg);
1711 reclaim = 0;
1712 goto retry;
1713 }
1714
1715 error = segvn_dup_pages(seg, newseg);
1716 if (error != 0) {
1717 newsvd->vpage = NULL;
1718 goto out;
1719 }
1720 } else { /* common case */
1721 if (seg->s_szc != 0) {
1722 /*
1723 * If at least one of anon slots of a
1724 * large page exists then make sure
1725 * all anon slots of a large page
1726 * exist to avoid partial cow sharing
1727 * of a large page in the future.
1728 */
1729 anon_dup_fill_holes(amp->ahp,
1730 svd->anon_index, newsvd->amp->ahp,
1731 0, seg->s_size, seg->s_szc,
1732 svd->vp != NULL);
1733 } else {
1734 anon_dup(amp->ahp, svd->anon_index,
1735 newsvd->amp->ahp, 0, seg->s_size);
1736 }
1737
1738 hat_clrattr(seg->s_as->a_hat, seg->s_base,
1739 seg->s_size, PROT_WRITE);
1740 }
1741 }
1742 }
1743 /*
1744 * If necessary, create a vpage structure for the new segment.
1745 * Do not copy any page lock indications.
1746 */
1747 if (svd->vpage != NULL) {
1748 uint_t i;
1749 struct vpage *ovp = svd->vpage;
1750 struct vpage *nvp;
1751
1752 nvp = newsvd->vpage =
1753 kmem_alloc(vpgtob(npages), KM_SLEEP);
1754 for (i = 0; i < npages; i++) {
1755 *nvp = *ovp++;
1756 VPP_CLRPPLOCK(nvp++);
1757 }
1758 } else
1759 newsvd->vpage = NULL;
1760
1761 /* Inform the vnode of the new mapping */
1762 if (newsvd->vp != NULL) {
1763 error = VOP_ADDMAP(newsvd->vp, (offset_t)newsvd->offset,
1764 newseg->s_as, newseg->s_base, newseg->s_size, newsvd->prot,
1765 newsvd->maxprot, newsvd->type, newsvd->cred, NULL);
1766 }
1767 out:
1768 if (error == 0 && HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
1769 ASSERT(newsvd->amp == NULL);
1770 ASSERT(newsvd->tr_state == SEGVN_TR_OFF);
1771 newsvd->rcookie = svd->rcookie;
1772 hat_dup_region(newseg->s_as->a_hat, newsvd->rcookie);
1773 }
1774 return (error);
1775 }
1776
1777
1778 /*
1779 * callback function to invoke free_vp_pages() for only those pages actually
1780 * processed by the HAT when a shared region is destroyed.
1781 */
1782 extern int free_pages;
1783
1784 static void
segvn_hat_rgn_unload_callback(caddr_t saddr,caddr_t eaddr,caddr_t r_saddr,size_t r_size,void * r_obj,u_offset_t r_objoff)1785 segvn_hat_rgn_unload_callback(caddr_t saddr, caddr_t eaddr, caddr_t r_saddr,
1786 size_t r_size, void *r_obj, u_offset_t r_objoff)
1787 {
1788 u_offset_t off;
1789 size_t len;
1790 vnode_t *vp = (vnode_t *)r_obj;
1791
1792 ASSERT(eaddr > saddr);
1793 ASSERT(saddr >= r_saddr);
1794 ASSERT(saddr < r_saddr + r_size);
1795 ASSERT(eaddr > r_saddr);
1796 ASSERT(eaddr <= r_saddr + r_size);
1797 ASSERT(vp != NULL);
1798
1799 if (!free_pages) {
1800 return;
1801 }
1802
1803 len = eaddr - saddr;
1804 off = (saddr - r_saddr) + r_objoff;
1805 free_vp_pages(vp, off, len);
1806 }
1807
1808 /*
1809 * callback function used by segvn_unmap to invoke free_vp_pages() for only
1810 * those pages actually processed by the HAT
1811 */
1812 static void
segvn_hat_unload_callback(hat_callback_t * cb)1813 segvn_hat_unload_callback(hat_callback_t *cb)
1814 {
1815 struct seg *seg = cb->hcb_data;
1816 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
1817 size_t len;
1818 u_offset_t off;
1819
1820 ASSERT(svd->vp != NULL);
1821 ASSERT(cb->hcb_end_addr > cb->hcb_start_addr);
1822 ASSERT(cb->hcb_start_addr >= seg->s_base);
1823
1824 len = cb->hcb_end_addr - cb->hcb_start_addr;
1825 off = cb->hcb_start_addr - seg->s_base;
1826 free_vp_pages(svd->vp, svd->offset + off, len);
1827 }
1828
1829 /*
1830 * This function determines the number of bytes of swap reserved by
1831 * a segment for which per-page accounting is present. It is used to
1832 * calculate the correct value of a segvn_data's swresv.
1833 */
1834 static size_t
segvn_count_swap_by_vpages(struct seg * seg)1835 segvn_count_swap_by_vpages(struct seg *seg)
1836 {
1837 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
1838 struct vpage *vp, *evp;
1839 size_t nswappages = 0;
1840
1841 ASSERT(svd->pageswap);
1842 ASSERT(svd->vpage != NULL);
1843
1844 evp = &svd->vpage[seg_page(seg, seg->s_base + seg->s_size)];
1845
1846 for (vp = svd->vpage; vp < evp; vp++) {
1847 if (VPP_ISSWAPRES(vp))
1848 nswappages++;
1849 }
1850
1851 return (nswappages << PAGESHIFT);
1852 }
1853
1854 static int
segvn_unmap(struct seg * seg,caddr_t addr,size_t len)1855 segvn_unmap(struct seg *seg, caddr_t addr, size_t len)
1856 {
1857 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
1858 struct segvn_data *nsvd;
1859 struct seg *nseg;
1860 struct anon_map *amp;
1861 pgcnt_t opages; /* old segment size in pages */
1862 pgcnt_t npages; /* new segment size in pages */
1863 pgcnt_t dpages; /* pages being deleted (unmapped) */
1864 hat_callback_t callback; /* used for free_vp_pages() */
1865 hat_callback_t *cbp = NULL;
1866 caddr_t nbase;
1867 size_t nsize;
1868 size_t oswresv;
1869 int reclaim = 1;
1870
1871 /*
1872 * We don't need any segment level locks for "segvn" data
1873 * since the address space is "write" locked.
1874 */
1875 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as));
1876
1877 /*
1878 * Fail the unmap if pages are SOFTLOCKed through this mapping.
1879 * softlockcnt is protected from change by the as write lock.
1880 */
1881 retry:
1882 if (svd->softlockcnt > 0) {
1883 ASSERT(svd->tr_state == SEGVN_TR_OFF);
1884
1885 /*
1886 * If this is shared segment non 0 softlockcnt
1887 * means locked pages are still in use.
1888 */
1889 if (svd->type == MAP_SHARED) {
1890 return (EAGAIN);
1891 }
1892
1893 /*
1894 * since we do have the writers lock nobody can fill
1895 * the cache during the purge. The flush either succeeds
1896 * or we still have pending I/Os.
1897 */
1898 if (reclaim == 1) {
1899 segvn_purge(seg);
1900 reclaim = 0;
1901 goto retry;
1902 }
1903 return (EAGAIN);
1904 }
1905
1906 /*
1907 * Check for bad sizes
1908 */
1909 if (addr < seg->s_base || addr + len > seg->s_base + seg->s_size ||
1910 (len & PAGEOFFSET) || ((uintptr_t)addr & PAGEOFFSET)) {
1911 panic("segvn_unmap");
1912 /*NOTREACHED*/
1913 }
1914
1915 if (seg->s_szc != 0) {
1916 size_t pgsz = page_get_pagesize(seg->s_szc);
1917 int err;
1918 if (!IS_P2ALIGNED(addr, pgsz) || !IS_P2ALIGNED(len, pgsz)) {
1919 ASSERT(seg->s_base != addr || seg->s_size != len);
1920 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
1921 ASSERT(svd->amp == NULL);
1922 ASSERT(svd->tr_state == SEGVN_TR_OFF);
1923 hat_leave_region(seg->s_as->a_hat,
1924 svd->rcookie, HAT_REGION_TEXT);
1925 svd->rcookie = HAT_INVALID_REGION_COOKIE;
1926 /*
1927 * could pass a flag to segvn_demote_range()
1928 * below to tell it not to do any unloads but
1929 * this case is rare enough to not bother for
1930 * now.
1931 */
1932 } else if (svd->tr_state == SEGVN_TR_INIT) {
1933 svd->tr_state = SEGVN_TR_OFF;
1934 } else if (svd->tr_state == SEGVN_TR_ON) {
1935 ASSERT(svd->amp != NULL);
1936 segvn_textunrepl(seg, 1);
1937 ASSERT(svd->amp == NULL);
1938 ASSERT(svd->tr_state == SEGVN_TR_OFF);
1939 }
1940 VM_STAT_ADD(segvnvmstats.demoterange[0]);
1941 err = segvn_demote_range(seg, addr, len, SDR_END, 0);
1942 if (err == 0) {
1943 return (IE_RETRY);
1944 }
1945 return (err);
1946 }
1947 }
1948
1949 /* Inform the vnode of the unmapping. */
1950 if (svd->vp) {
1951 int error;
1952
1953 error = VOP_DELMAP(svd->vp,
1954 (offset_t)svd->offset + (uintptr_t)(addr - seg->s_base),
1955 seg->s_as, addr, len, svd->prot, svd->maxprot,
1956 svd->type, svd->cred, NULL);
1957
1958 if (error == EAGAIN)
1959 return (error);
1960 }
1961
1962 /*
1963 * Remove any page locks set through this mapping.
1964 * If text replication is not off no page locks could have been
1965 * established via this mapping.
1966 */
1967 if (svd->tr_state == SEGVN_TR_OFF) {
1968 (void) segvn_lockop(seg, addr, len, 0, MC_UNLOCK, NULL, 0);
1969 }
1970
1971 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
1972 ASSERT(svd->amp == NULL);
1973 ASSERT(svd->tr_state == SEGVN_TR_OFF);
1974 ASSERT(svd->type == MAP_PRIVATE);
1975 hat_leave_region(seg->s_as->a_hat, svd->rcookie,
1976 HAT_REGION_TEXT);
1977 svd->rcookie = HAT_INVALID_REGION_COOKIE;
1978 } else if (svd->tr_state == SEGVN_TR_ON) {
1979 ASSERT(svd->amp != NULL);
1980 ASSERT(svd->pageprot == 0 && !(svd->prot & PROT_WRITE));
1981 segvn_textunrepl(seg, 1);
1982 ASSERT(svd->amp == NULL && svd->tr_state == SEGVN_TR_OFF);
1983 } else {
1984 if (svd->tr_state != SEGVN_TR_OFF) {
1985 ASSERT(svd->tr_state == SEGVN_TR_INIT);
1986 svd->tr_state = SEGVN_TR_OFF;
1987 }
1988 /*
1989 * Unload any hardware translations in the range to be taken
1990 * out. Use a callback to invoke free_vp_pages() effectively.
1991 */
1992 if (svd->vp != NULL && free_pages != 0) {
1993 callback.hcb_data = seg;
1994 callback.hcb_function = segvn_hat_unload_callback;
1995 cbp = &callback;
1996 }
1997 hat_unload_callback(seg->s_as->a_hat, addr, len,
1998 HAT_UNLOAD_UNMAP, cbp);
1999
2000 if (svd->type == MAP_SHARED && svd->vp != NULL &&
2001 (svd->vp->v_flag & VVMEXEC) &&
2002 ((svd->prot & PROT_WRITE) || svd->pageprot)) {
2003 segvn_inval_trcache(svd->vp);
2004 }
2005 }
2006
2007 /*
2008 * Check for entire segment
2009 */
2010 if (addr == seg->s_base && len == seg->s_size) {
2011 seg_free(seg);
2012 return (0);
2013 }
2014
2015 opages = seg_pages(seg);
2016 dpages = btop(len);
2017 npages = opages - dpages;
2018 amp = svd->amp;
2019 ASSERT(amp == NULL || amp->a_szc >= seg->s_szc);
2020
2021 /*
2022 * Check for beginning of segment
2023 */
2024 if (addr == seg->s_base) {
2025 if (svd->vpage != NULL) {
2026 size_t nbytes;
2027 struct vpage *ovpage;
2028
2029 ovpage = svd->vpage; /* keep pointer to vpage */
2030
2031 nbytes = vpgtob(npages);
2032 svd->vpage = kmem_alloc(nbytes, KM_SLEEP);
2033 bcopy(&ovpage[dpages], svd->vpage, nbytes);
2034
2035 /* free up old vpage */
2036 kmem_free(ovpage, vpgtob(opages));
2037 }
2038 if (amp != NULL) {
2039 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
2040 if (amp->refcnt == 1 || svd->type == MAP_PRIVATE) {
2041 /*
2042 * Shared anon map is no longer in use. Before
2043 * freeing its pages purge all entries from
2044 * pcache that belong to this amp.
2045 */
2046 if (svd->type == MAP_SHARED) {
2047 ASSERT(amp->refcnt == 1);
2048 ASSERT(svd->softlockcnt == 0);
2049 anonmap_purge(amp);
2050 }
2051 /*
2052 * Free up now unused parts of anon_map array.
2053 */
2054 if (amp->a_szc == seg->s_szc) {
2055 if (seg->s_szc != 0) {
2056 anon_free_pages(amp->ahp,
2057 svd->anon_index, len,
2058 seg->s_szc);
2059 } else {
2060 anon_free(amp->ahp,
2061 svd->anon_index,
2062 len);
2063 }
2064 } else {
2065 ASSERT(svd->type == MAP_SHARED);
2066 ASSERT(amp->a_szc > seg->s_szc);
2067 anon_shmap_free_pages(amp,
2068 svd->anon_index, len);
2069 }
2070
2071 /*
2072 * Unreserve swap space for the
2073 * unmapped chunk of this segment in
2074 * case it's MAP_SHARED
2075 */
2076 if (svd->type == MAP_SHARED) {
2077 anon_unresv_zone(len,
2078 seg->s_as->a_proc->p_zone);
2079 amp->swresv -= len;
2080 }
2081 }
2082 ANON_LOCK_EXIT(&->a_rwlock);
2083 svd->anon_index += dpages;
2084 }
2085 if (svd->vp != NULL)
2086 svd->offset += len;
2087
2088 seg->s_base += len;
2089 seg->s_size -= len;
2090
2091 if (svd->swresv) {
2092 if (svd->flags & MAP_NORESERVE) {
2093 ASSERT(amp);
2094 oswresv = svd->swresv;
2095
2096 svd->swresv = ptob(anon_pages(amp->ahp,
2097 svd->anon_index, npages));
2098 anon_unresv_zone(oswresv - svd->swresv,
2099 seg->s_as->a_proc->p_zone);
2100 if (SEG_IS_PARTIAL_RESV(seg))
2101 seg->s_as->a_resvsize -= oswresv -
2102 svd->swresv;
2103 } else {
2104 size_t unlen;
2105
2106 if (svd->pageswap) {
2107 oswresv = svd->swresv;
2108 svd->swresv =
2109 segvn_count_swap_by_vpages(seg);
2110 ASSERT(oswresv >= svd->swresv);
2111 unlen = oswresv - svd->swresv;
2112 } else {
2113 svd->swresv -= len;
2114 ASSERT(svd->swresv == seg->s_size);
2115 unlen = len;
2116 }
2117 anon_unresv_zone(unlen,
2118 seg->s_as->a_proc->p_zone);
2119 }
2120 TRACE_3(TR_FAC_VM, TR_ANON_PROC, "anon proc:%p %lu %u",
2121 seg, len, 0);
2122 }
2123
2124 return (0);
2125 }
2126
2127 /*
2128 * Check for end of segment
2129 */
2130 if (addr + len == seg->s_base + seg->s_size) {
2131 if (svd->vpage != NULL) {
2132 size_t nbytes;
2133 struct vpage *ovpage;
2134
2135 ovpage = svd->vpage; /* keep pointer to vpage */
2136
2137 nbytes = vpgtob(npages);
2138 svd->vpage = kmem_alloc(nbytes, KM_SLEEP);
2139 bcopy(ovpage, svd->vpage, nbytes);
2140
2141 /* free up old vpage */
2142 kmem_free(ovpage, vpgtob(opages));
2143
2144 }
2145 if (amp != NULL) {
2146 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
2147 if (amp->refcnt == 1 || svd->type == MAP_PRIVATE) {
2148 /*
2149 * Free up now unused parts of anon_map array.
2150 */
2151 ulong_t an_idx = svd->anon_index + npages;
2152
2153 /*
2154 * Shared anon map is no longer in use. Before
2155 * freeing its pages purge all entries from
2156 * pcache that belong to this amp.
2157 */
2158 if (svd->type == MAP_SHARED) {
2159 ASSERT(amp->refcnt == 1);
2160 ASSERT(svd->softlockcnt == 0);
2161 anonmap_purge(amp);
2162 }
2163
2164 if (amp->a_szc == seg->s_szc) {
2165 if (seg->s_szc != 0) {
2166 anon_free_pages(amp->ahp,
2167 an_idx, len,
2168 seg->s_szc);
2169 } else {
2170 anon_free(amp->ahp, an_idx,
2171 len);
2172 }
2173 } else {
2174 ASSERT(svd->type == MAP_SHARED);
2175 ASSERT(amp->a_szc > seg->s_szc);
2176 anon_shmap_free_pages(amp,
2177 an_idx, len);
2178 }
2179
2180 /*
2181 * Unreserve swap space for the
2182 * unmapped chunk of this segment in
2183 * case it's MAP_SHARED
2184 */
2185 if (svd->type == MAP_SHARED) {
2186 anon_unresv_zone(len,
2187 seg->s_as->a_proc->p_zone);
2188 amp->swresv -= len;
2189 }
2190 }
2191 ANON_LOCK_EXIT(&->a_rwlock);
2192 }
2193
2194 seg->s_size -= len;
2195
2196 if (svd->swresv) {
2197 if (svd->flags & MAP_NORESERVE) {
2198 ASSERT(amp);
2199 oswresv = svd->swresv;
2200 svd->swresv = ptob(anon_pages(amp->ahp,
2201 svd->anon_index, npages));
2202 anon_unresv_zone(oswresv - svd->swresv,
2203 seg->s_as->a_proc->p_zone);
2204 if (SEG_IS_PARTIAL_RESV(seg))
2205 seg->s_as->a_resvsize -= oswresv -
2206 svd->swresv;
2207 } else {
2208 size_t unlen;
2209
2210 if (svd->pageswap) {
2211 oswresv = svd->swresv;
2212 svd->swresv =
2213 segvn_count_swap_by_vpages(seg);
2214 ASSERT(oswresv >= svd->swresv);
2215 unlen = oswresv - svd->swresv;
2216 } else {
2217 svd->swresv -= len;
2218 ASSERT(svd->swresv == seg->s_size);
2219 unlen = len;
2220 }
2221 anon_unresv_zone(unlen,
2222 seg->s_as->a_proc->p_zone);
2223 }
2224 TRACE_3(TR_FAC_VM, TR_ANON_PROC,
2225 "anon proc:%p %lu %u", seg, len, 0);
2226 }
2227
2228 return (0);
2229 }
2230
2231 /*
2232 * The section to go is in the middle of the segment,
2233 * have to make it into two segments. nseg is made for
2234 * the high end while seg is cut down at the low end.
2235 */
2236 nbase = addr + len; /* new seg base */
2237 nsize = (seg->s_base + seg->s_size) - nbase; /* new seg size */
2238 seg->s_size = addr - seg->s_base; /* shrink old seg */
2239 nseg = seg_alloc(seg->s_as, nbase, nsize);
2240 if (nseg == NULL) {
2241 panic("segvn_unmap seg_alloc");
2242 /*NOTREACHED*/
2243 }
2244 nseg->s_ops = seg->s_ops;
2245 nsvd = kmem_cache_alloc(segvn_cache, KM_SLEEP);
2246 nseg->s_data = (void *)nsvd;
2247 nseg->s_szc = seg->s_szc;
2248 *nsvd = *svd;
2249 nsvd->seg = nseg;
2250 nsvd->offset = svd->offset + (uintptr_t)(nseg->s_base - seg->s_base);
2251 nsvd->swresv = 0;
2252 nsvd->softlockcnt = 0;
2253 nsvd->softlockcnt_sbase = 0;
2254 nsvd->softlockcnt_send = 0;
2255 nsvd->svn_inz = svd->svn_inz;
2256 ASSERT(nsvd->rcookie == HAT_INVALID_REGION_COOKIE);
2257
2258 if (svd->vp != NULL) {
2259 VN_HOLD(nsvd->vp);
2260 if (nsvd->type == MAP_SHARED)
2261 lgrp_shm_policy_init(NULL, nsvd->vp);
2262 }
2263 crhold(svd->cred);
2264
2265 if (svd->vpage == NULL) {
2266 nsvd->vpage = NULL;
2267 } else {
2268 /* need to split vpage into two arrays */
2269 size_t nbytes;
2270 struct vpage *ovpage;
2271
2272 ovpage = svd->vpage; /* keep pointer to vpage */
2273
2274 npages = seg_pages(seg); /* seg has shrunk */
2275 nbytes = vpgtob(npages);
2276 svd->vpage = kmem_alloc(nbytes, KM_SLEEP);
2277
2278 bcopy(ovpage, svd->vpage, nbytes);
2279
2280 npages = seg_pages(nseg);
2281 nbytes = vpgtob(npages);
2282 nsvd->vpage = kmem_alloc(nbytes, KM_SLEEP);
2283
2284 bcopy(&ovpage[opages - npages], nsvd->vpage, nbytes);
2285
2286 /* free up old vpage */
2287 kmem_free(ovpage, vpgtob(opages));
2288 }
2289
2290 if (amp == NULL) {
2291 nsvd->amp = NULL;
2292 nsvd->anon_index = 0;
2293 } else {
2294 /*
2295 * Need to create a new anon map for the new segment.
2296 * We'll also allocate a new smaller array for the old
2297 * smaller segment to save space.
2298 */
2299 opages = btop((uintptr_t)(addr - seg->s_base));
2300 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
2301 if (amp->refcnt == 1 || svd->type == MAP_PRIVATE) {
2302 /*
2303 * Free up now unused parts of anon_map array.
2304 */
2305 ulong_t an_idx = svd->anon_index + opages;
2306
2307 /*
2308 * Shared anon map is no longer in use. Before
2309 * freeing its pages purge all entries from
2310 * pcache that belong to this amp.
2311 */
2312 if (svd->type == MAP_SHARED) {
2313 ASSERT(amp->refcnt == 1);
2314 ASSERT(svd->softlockcnt == 0);
2315 anonmap_purge(amp);
2316 }
2317
2318 if (amp->a_szc == seg->s_szc) {
2319 if (seg->s_szc != 0) {
2320 anon_free_pages(amp->ahp, an_idx, len,
2321 seg->s_szc);
2322 } else {
2323 anon_free(amp->ahp, an_idx,
2324 len);
2325 }
2326 } else {
2327 ASSERT(svd->type == MAP_SHARED);
2328 ASSERT(amp->a_szc > seg->s_szc);
2329 anon_shmap_free_pages(amp, an_idx, len);
2330 }
2331
2332 /*
2333 * Unreserve swap space for the
2334 * unmapped chunk of this segment in
2335 * case it's MAP_SHARED
2336 */
2337 if (svd->type == MAP_SHARED) {
2338 anon_unresv_zone(len,
2339 seg->s_as->a_proc->p_zone);
2340 amp->swresv -= len;
2341 }
2342 }
2343 nsvd->anon_index = svd->anon_index +
2344 btop((uintptr_t)(nseg->s_base - seg->s_base));
2345 if (svd->type == MAP_SHARED) {
2346 amp->refcnt++;
2347 nsvd->amp = amp;
2348 } else {
2349 struct anon_map *namp;
2350 struct anon_hdr *nahp;
2351
2352 ASSERT(svd->type == MAP_PRIVATE);
2353 nahp = anon_create(btop(seg->s_size), ANON_SLEEP);
2354 namp = anonmap_alloc(nseg->s_size, 0, ANON_SLEEP);
2355 namp->a_szc = seg->s_szc;
2356 (void) anon_copy_ptr(amp->ahp, svd->anon_index, nahp,
2357 0, btop(seg->s_size), ANON_SLEEP);
2358 (void) anon_copy_ptr(amp->ahp, nsvd->anon_index,
2359 namp->ahp, 0, btop(nseg->s_size), ANON_SLEEP);
2360 anon_release(amp->ahp, btop(amp->size));
2361 svd->anon_index = 0;
2362 nsvd->anon_index = 0;
2363 amp->ahp = nahp;
2364 amp->size = seg->s_size;
2365 nsvd->amp = namp;
2366 }
2367 ANON_LOCK_EXIT(&->a_rwlock);
2368 }
2369 if (svd->swresv) {
2370 if (svd->flags & MAP_NORESERVE) {
2371 ASSERT(amp);
2372 oswresv = svd->swresv;
2373 svd->swresv = ptob(anon_pages(amp->ahp,
2374 svd->anon_index, btop(seg->s_size)));
2375 nsvd->swresv = ptob(anon_pages(nsvd->amp->ahp,
2376 nsvd->anon_index, btop(nseg->s_size)));
2377 ASSERT(oswresv >= (svd->swresv + nsvd->swresv));
2378 anon_unresv_zone(oswresv - (svd->swresv + nsvd->swresv),
2379 seg->s_as->a_proc->p_zone);
2380 if (SEG_IS_PARTIAL_RESV(seg))
2381 seg->s_as->a_resvsize -= oswresv -
2382 (svd->swresv + nsvd->swresv);
2383 } else {
2384 size_t unlen;
2385
2386 if (svd->pageswap) {
2387 oswresv = svd->swresv;
2388 svd->swresv = segvn_count_swap_by_vpages(seg);
2389 nsvd->swresv = segvn_count_swap_by_vpages(nseg);
2390 ASSERT(oswresv >= (svd->swresv + nsvd->swresv));
2391 unlen = oswresv - (svd->swresv + nsvd->swresv);
2392 } else {
2393 if (seg->s_size + nseg->s_size + len !=
2394 svd->swresv) {
2395 panic("segvn_unmap: cannot split "
2396 "swap reservation");
2397 /*NOTREACHED*/
2398 }
2399 svd->swresv = seg->s_size;
2400 nsvd->swresv = nseg->s_size;
2401 unlen = len;
2402 }
2403 anon_unresv_zone(unlen,
2404 seg->s_as->a_proc->p_zone);
2405 }
2406 TRACE_3(TR_FAC_VM, TR_ANON_PROC, "anon proc:%p %lu %u",
2407 seg, len, 0);
2408 }
2409
2410 return (0); /* I'm glad that's all over with! */
2411 }
2412
2413 static void
segvn_free(struct seg * seg)2414 segvn_free(struct seg *seg)
2415 {
2416 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
2417 pgcnt_t npages = seg_pages(seg);
2418 struct anon_map *amp;
2419 size_t len;
2420
2421 /*
2422 * We don't need any segment level locks for "segvn" data
2423 * since the address space is "write" locked.
2424 */
2425 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as));
2426 ASSERT(svd->tr_state == SEGVN_TR_OFF);
2427
2428 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
2429
2430 /*
2431 * Be sure to unlock pages. XXX Why do things get free'ed instead
2432 * of unmapped? XXX
2433 */
2434 (void) segvn_lockop(seg, seg->s_base, seg->s_size,
2435 0, MC_UNLOCK, NULL, 0);
2436
2437 /*
2438 * Deallocate the vpage and anon pointers if necessary and possible.
2439 */
2440 if (svd->vpage != NULL) {
2441 kmem_free(svd->vpage, vpgtob(npages));
2442 svd->vpage = NULL;
2443 }
2444 if ((amp = svd->amp) != NULL) {
2445 /*
2446 * If there are no more references to this anon_map
2447 * structure, then deallocate the structure after freeing
2448 * up all the anon slot pointers that we can.
2449 */
2450 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
2451 ASSERT(amp->a_szc >= seg->s_szc);
2452 if (--amp->refcnt == 0) {
2453 if (svd->type == MAP_PRIVATE) {
2454 /*
2455 * Private - we only need to anon_free
2456 * the part that this segment refers to.
2457 */
2458 if (seg->s_szc != 0) {
2459 anon_free_pages(amp->ahp,
2460 svd->anon_index, seg->s_size,
2461 seg->s_szc);
2462 } else {
2463 anon_free(amp->ahp, svd->anon_index,
2464 seg->s_size);
2465 }
2466 } else {
2467
2468 /*
2469 * Shared anon map is no longer in use. Before
2470 * freeing its pages purge all entries from
2471 * pcache that belong to this amp.
2472 */
2473 ASSERT(svd->softlockcnt == 0);
2474 anonmap_purge(amp);
2475
2476 /*
2477 * Shared - anon_free the entire
2478 * anon_map's worth of stuff and
2479 * release any swap reservation.
2480 */
2481 if (amp->a_szc != 0) {
2482 anon_shmap_free_pages(amp, 0,
2483 amp->size);
2484 } else {
2485 anon_free(amp->ahp, 0, amp->size);
2486 }
2487 if ((len = amp->swresv) != 0) {
2488 anon_unresv_zone(len,
2489 seg->s_as->a_proc->p_zone);
2490 TRACE_3(TR_FAC_VM, TR_ANON_PROC,
2491 "anon proc:%p %lu %u", seg, len, 0);
2492 }
2493 }
2494 svd->amp = NULL;
2495 ANON_LOCK_EXIT(&->a_rwlock);
2496 anonmap_free(amp);
2497 } else if (svd->type == MAP_PRIVATE) {
2498 /*
2499 * We had a private mapping which still has
2500 * a held anon_map so just free up all the
2501 * anon slot pointers that we were using.
2502 */
2503 if (seg->s_szc != 0) {
2504 anon_free_pages(amp->ahp, svd->anon_index,
2505 seg->s_size, seg->s_szc);
2506 } else {
2507 anon_free(amp->ahp, svd->anon_index,
2508 seg->s_size);
2509 }
2510 ANON_LOCK_EXIT(&->a_rwlock);
2511 } else {
2512 ANON_LOCK_EXIT(&->a_rwlock);
2513 }
2514 }
2515
2516 /*
2517 * Release swap reservation.
2518 */
2519 if ((len = svd->swresv) != 0) {
2520 anon_unresv_zone(svd->swresv,
2521 seg->s_as->a_proc->p_zone);
2522 TRACE_3(TR_FAC_VM, TR_ANON_PROC, "anon proc:%p %lu %u",
2523 seg, len, 0);
2524 if (SEG_IS_PARTIAL_RESV(seg))
2525 seg->s_as->a_resvsize -= svd->swresv;
2526 svd->swresv = 0;
2527 }
2528 /*
2529 * Release claim on vnode, credentials, and finally free the
2530 * private data.
2531 */
2532 if (svd->vp != NULL) {
2533 if (svd->type == MAP_SHARED)
2534 lgrp_shm_policy_fini(NULL, svd->vp);
2535 VN_RELE(svd->vp);
2536 svd->vp = NULL;
2537 }
2538 crfree(svd->cred);
2539 svd->pageprot = 0;
2540 svd->pageadvice = 0;
2541 svd->pageswap = 0;
2542 svd->cred = NULL;
2543
2544 /*
2545 * Take segfree_syncmtx lock to let segvn_reclaim() finish if it's
2546 * still working with this segment without holding as lock (in case
2547 * it's called by pcache async thread).
2548 */
2549 ASSERT(svd->softlockcnt == 0);
2550 mutex_enter(&svd->segfree_syncmtx);
2551 mutex_exit(&svd->segfree_syncmtx);
2552
2553 seg->s_data = NULL;
2554 kmem_cache_free(segvn_cache, svd);
2555 }
2556
2557 /*
2558 * Do a F_SOFTUNLOCK call over the range requested. The range must have
2559 * already been F_SOFTLOCK'ed.
2560 * Caller must always match addr and len of a softunlock with a previous
2561 * softlock with exactly the same addr and len.
2562 */
2563 static void
segvn_softunlock(struct seg * seg,caddr_t addr,size_t len,enum seg_rw rw)2564 segvn_softunlock(struct seg *seg, caddr_t addr, size_t len, enum seg_rw rw)
2565 {
2566 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
2567 page_t *pp;
2568 caddr_t adr;
2569 struct vnode *vp;
2570 u_offset_t offset;
2571 ulong_t anon_index;
2572 struct anon_map *amp;
2573 struct anon *ap = NULL;
2574
2575 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
2576 ASSERT(SEGVN_LOCK_HELD(seg->s_as, &svd->lock));
2577
2578 if ((amp = svd->amp) != NULL)
2579 anon_index = svd->anon_index + seg_page(seg, addr);
2580
2581 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
2582 ASSERT(svd->tr_state == SEGVN_TR_OFF);
2583 hat_unlock_region(seg->s_as->a_hat, addr, len, svd->rcookie);
2584 } else {
2585 hat_unlock(seg->s_as->a_hat, addr, len);
2586 }
2587 for (adr = addr; adr < addr + len; adr += PAGESIZE) {
2588 if (amp != NULL) {
2589 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
2590 if ((ap = anon_get_ptr(amp->ahp, anon_index++))
2591 != NULL) {
2592 swap_xlate(ap, &vp, &offset);
2593 } else {
2594 vp = svd->vp;
2595 offset = svd->offset +
2596 (uintptr_t)(adr - seg->s_base);
2597 }
2598 ANON_LOCK_EXIT(&->a_rwlock);
2599 } else {
2600 vp = svd->vp;
2601 offset = svd->offset +
2602 (uintptr_t)(adr - seg->s_base);
2603 }
2604
2605 /*
2606 * Use page_find() instead of page_lookup() to
2607 * find the page since we know that it is locked.
2608 */
2609 pp = page_find(vp, offset);
2610 if (pp == NULL) {
2611 panic(
2612 "segvn_softunlock: addr %p, ap %p, vp %p, off %llx",
2613 (void *)adr, (void *)ap, (void *)vp, offset);
2614 /*NOTREACHED*/
2615 }
2616
2617 if (rw == S_WRITE) {
2618 hat_setrefmod(pp);
2619 if (seg->s_as->a_vbits)
2620 hat_setstat(seg->s_as, adr, PAGESIZE,
2621 P_REF | P_MOD);
2622 } else if (rw != S_OTHER) {
2623 hat_setref(pp);
2624 if (seg->s_as->a_vbits)
2625 hat_setstat(seg->s_as, adr, PAGESIZE, P_REF);
2626 }
2627 TRACE_3(TR_FAC_VM, TR_SEGVN_FAULT,
2628 "segvn_fault:pp %p vp %p offset %llx", pp, vp, offset);
2629 page_unlock(pp);
2630 }
2631 ASSERT(svd->softlockcnt >= btop(len));
2632 if (!atomic_add_long_nv((ulong_t *)&svd->softlockcnt, -btop(len))) {
2633 /*
2634 * All SOFTLOCKS are gone. Wakeup any waiting
2635 * unmappers so they can try again to unmap.
2636 * Check for waiters first without the mutex
2637 * held so we don't always grab the mutex on
2638 * softunlocks.
2639 */
2640 if (AS_ISUNMAPWAIT(seg->s_as)) {
2641 mutex_enter(&seg->s_as->a_contents);
2642 if (AS_ISUNMAPWAIT(seg->s_as)) {
2643 AS_CLRUNMAPWAIT(seg->s_as);
2644 cv_broadcast(&seg->s_as->a_cv);
2645 }
2646 mutex_exit(&seg->s_as->a_contents);
2647 }
2648 }
2649 }
2650
2651 #define PAGE_HANDLED ((page_t *)-1)
2652
2653 /*
2654 * Release all the pages in the NULL terminated ppp list
2655 * which haven't already been converted to PAGE_HANDLED.
2656 */
2657 static void
segvn_pagelist_rele(page_t ** ppp)2658 segvn_pagelist_rele(page_t **ppp)
2659 {
2660 for (; *ppp != NULL; ppp++) {
2661 if (*ppp != PAGE_HANDLED)
2662 page_unlock(*ppp);
2663 }
2664 }
2665
2666 static int stealcow = 1;
2667
2668 /*
2669 * Workaround for viking chip bug. See bug id 1220902.
2670 * To fix this down in pagefault() would require importing so
2671 * much as and segvn code as to be unmaintainable.
2672 */
2673 int enable_mbit_wa = 0;
2674
2675 /*
2676 * Handles all the dirty work of getting the right
2677 * anonymous pages and loading up the translations.
2678 * This routine is called only from segvn_fault()
2679 * when looping over the range of addresses requested.
2680 *
2681 * The basic algorithm here is:
2682 * If this is an anon_zero case
2683 * Call anon_zero to allocate page
2684 * Load up translation
2685 * Return
2686 * endif
2687 * If this is an anon page
2688 * Use anon_getpage to get the page
2689 * else
2690 * Find page in pl[] list passed in
2691 * endif
2692 * If not a cow
2693 * Load up the translation to the page
2694 * return
2695 * endif
2696 * Call anon_private to handle cow
2697 * Load up (writable) translation to new page
2698 */
2699 static faultcode_t
segvn_faultpage(struct hat * hat,struct seg * seg,caddr_t addr,u_offset_t off,struct vpage * vpage,page_t * pl[],uint_t vpprot,enum fault_type type,enum seg_rw rw,int brkcow)2700 segvn_faultpage(
2701 struct hat *hat, /* the hat to use for mapping */
2702 struct seg *seg, /* seg_vn of interest */
2703 caddr_t addr, /* address in as */
2704 u_offset_t off, /* offset in vp */
2705 struct vpage *vpage, /* pointer to vpage for vp, off */
2706 page_t *pl[], /* object source page pointer */
2707 uint_t vpprot, /* access allowed to object pages */
2708 enum fault_type type, /* type of fault */
2709 enum seg_rw rw, /* type of access at fault */
2710 int brkcow) /* we may need to break cow */
2711 {
2712 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
2713 page_t *pp, **ppp;
2714 uint_t pageflags = 0;
2715 page_t *anon_pl[1 + 1];
2716 page_t *opp = NULL; /* original page */
2717 uint_t prot;
2718 int err;
2719 int cow;
2720 int claim;
2721 int steal = 0;
2722 ulong_t anon_index;
2723 struct anon *ap, *oldap;
2724 struct anon_map *amp;
2725 int hat_flag = (type == F_SOFTLOCK) ? HAT_LOAD_LOCK : HAT_LOAD;
2726 int anon_lock = 0;
2727 anon_sync_obj_t cookie;
2728
2729 if (svd->flags & MAP_TEXT) {
2730 hat_flag |= HAT_LOAD_TEXT;
2731 }
2732
2733 ASSERT(SEGVN_READ_HELD(seg->s_as, &svd->lock));
2734 ASSERT(seg->s_szc == 0);
2735 ASSERT(svd->tr_state != SEGVN_TR_INIT);
2736
2737 /*
2738 * Initialize protection value for this page.
2739 * If we have per page protection values check it now.
2740 */
2741 if (svd->pageprot) {
2742 uint_t protchk;
2743
2744 switch (rw) {
2745 case S_READ:
2746 protchk = PROT_READ;
2747 break;
2748 case S_WRITE:
2749 protchk = PROT_WRITE;
2750 break;
2751 case S_EXEC:
2752 protchk = PROT_EXEC;
2753 break;
2754 case S_OTHER:
2755 default:
2756 protchk = PROT_READ | PROT_WRITE | PROT_EXEC;
2757 break;
2758 }
2759
2760 prot = VPP_PROT(vpage);
2761 if ((prot & protchk) == 0)
2762 return (FC_PROT); /* illegal access type */
2763 } else {
2764 prot = svd->prot;
2765 }
2766
2767 if (type == F_SOFTLOCK) {
2768 atomic_inc_ulong((ulong_t *)&svd->softlockcnt);
2769 }
2770
2771 /*
2772 * Always acquire the anon array lock to prevent 2 threads from
2773 * allocating separate anon slots for the same "addr".
2774 */
2775
2776 if ((amp = svd->amp) != NULL) {
2777 ASSERT(RW_READ_HELD(&->a_rwlock));
2778 anon_index = svd->anon_index + seg_page(seg, addr);
2779 anon_array_enter(amp, anon_index, &cookie);
2780 anon_lock = 1;
2781 }
2782
2783 if (svd->vp == NULL && amp != NULL) {
2784 if ((ap = anon_get_ptr(amp->ahp, anon_index)) == NULL) {
2785 /*
2786 * Allocate a (normally) writable anonymous page of
2787 * zeroes. If no advance reservations, reserve now.
2788 */
2789 if (svd->flags & MAP_NORESERVE) {
2790 if (anon_resv_zone(ptob(1),
2791 seg->s_as->a_proc->p_zone)) {
2792 atomic_add_long(&svd->swresv, ptob(1));
2793 atomic_add_long(&seg->s_as->a_resvsize,
2794 ptob(1));
2795 } else {
2796 err = ENOMEM;
2797 goto out;
2798 }
2799 }
2800 if ((pp = anon_zero(seg, addr, &ap,
2801 svd->cred)) == NULL) {
2802 err = ENOMEM;
2803 goto out; /* out of swap space */
2804 }
2805 /*
2806 * Re-acquire the anon_map lock and
2807 * initialize the anon array entry.
2808 */
2809 (void) anon_set_ptr(amp->ahp, anon_index, ap,
2810 ANON_SLEEP);
2811
2812 ASSERT(pp->p_szc == 0);
2813
2814 /*
2815 * Handle pages that have been marked for migration
2816 */
2817 if (lgrp_optimizations())
2818 page_migrate(seg, addr, &pp, 1);
2819
2820 if (enable_mbit_wa) {
2821 if (rw == S_WRITE)
2822 hat_setmod(pp);
2823 else if (!hat_ismod(pp))
2824 prot &= ~PROT_WRITE;
2825 }
2826 /*
2827 * If AS_PAGLCK is set in a_flags (via memcntl(2)
2828 * with MC_LOCKAS, MCL_FUTURE) and this is a
2829 * MAP_NORESERVE segment, we may need to
2830 * permanently lock the page as it is being faulted
2831 * for the first time. The following text applies
2832 * only to MAP_NORESERVE segments:
2833 *
2834 * As per memcntl(2), if this segment was created
2835 * after MCL_FUTURE was applied (a "future"
2836 * segment), its pages must be locked. If this
2837 * segment existed at MCL_FUTURE application (a
2838 * "past" segment), the interface is unclear.
2839 *
2840 * We decide to lock only if vpage is present:
2841 *
2842 * - "future" segments will have a vpage array (see
2843 * as_map), and so will be locked as required
2844 *
2845 * - "past" segments may not have a vpage array,
2846 * depending on whether events (such as
2847 * mprotect) have occurred. Locking if vpage
2848 * exists will preserve legacy behavior. Not
2849 * locking if vpage is absent, will not break
2850 * the interface or legacy behavior. Note that
2851 * allocating vpage here if it's absent requires
2852 * upgrading the segvn reader lock, the cost of
2853 * which does not seem worthwhile.
2854 *
2855 * Usually testing and setting VPP_ISPPLOCK and
2856 * VPP_SETPPLOCK requires holding the segvn lock as
2857 * writer, but in this case all readers are
2858 * serializing on the anon array lock.
2859 */
2860 if (AS_ISPGLCK(seg->s_as) && vpage != NULL &&
2861 (svd->flags & MAP_NORESERVE) &&
2862 !VPP_ISPPLOCK(vpage)) {
2863 proc_t *p = seg->s_as->a_proc;
2864 ASSERT(svd->type == MAP_PRIVATE);
2865 mutex_enter(&p->p_lock);
2866 if (rctl_incr_locked_mem(p, NULL, PAGESIZE,
2867 1) == 0) {
2868 claim = VPP_PROT(vpage) & PROT_WRITE;
2869 if (page_pp_lock(pp, claim, 0)) {
2870 VPP_SETPPLOCK(vpage);
2871 } else {
2872 rctl_decr_locked_mem(p, NULL,
2873 PAGESIZE, 1);
2874 }
2875 }
2876 mutex_exit(&p->p_lock);
2877 }
2878
2879 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
2880 hat_memload(hat, addr, pp, prot, hat_flag);
2881
2882 if (!(hat_flag & HAT_LOAD_LOCK))
2883 page_unlock(pp);
2884
2885 anon_array_exit(&cookie);
2886 return (0);
2887 }
2888 }
2889
2890 /*
2891 * Obtain the page structure via anon_getpage() if it is
2892 * a private copy of an object (the result of a previous
2893 * copy-on-write).
2894 */
2895 if (amp != NULL) {
2896 if ((ap = anon_get_ptr(amp->ahp, anon_index)) != NULL) {
2897 err = anon_getpage(&ap, &vpprot, anon_pl, PAGESIZE,
2898 seg, addr, rw, svd->cred);
2899 if (err)
2900 goto out;
2901
2902 if (svd->type == MAP_SHARED) {
2903 /*
2904 * If this is a shared mapping to an
2905 * anon_map, then ignore the write
2906 * permissions returned by anon_getpage().
2907 * They apply to the private mappings
2908 * of this anon_map.
2909 */
2910 vpprot |= PROT_WRITE;
2911 }
2912 opp = anon_pl[0];
2913 }
2914 }
2915
2916 /*
2917 * Search the pl[] list passed in if it is from the
2918 * original object (i.e., not a private copy).
2919 */
2920 if (opp == NULL) {
2921 /*
2922 * Find original page. We must be bringing it in
2923 * from the list in pl[].
2924 */
2925 for (ppp = pl; (opp = *ppp) != NULL; ppp++) {
2926 if (opp == PAGE_HANDLED)
2927 continue;
2928 ASSERT(opp->p_vnode == svd->vp); /* XXX */
2929 if (opp->p_offset == off)
2930 break;
2931 }
2932 if (opp == NULL) {
2933 panic("segvn_faultpage not found");
2934 /*NOTREACHED*/
2935 }
2936 *ppp = PAGE_HANDLED;
2937
2938 }
2939
2940 ASSERT(PAGE_LOCKED(opp));
2941
2942 TRACE_3(TR_FAC_VM, TR_SEGVN_FAULT,
2943 "segvn_fault:pp %p vp %p offset %llx", opp, NULL, 0);
2944
2945 /*
2946 * The fault is treated as a copy-on-write fault if a
2947 * write occurs on a private segment and the object
2948 * page (i.e., mapping) is write protected. We assume
2949 * that fatal protection checks have already been made.
2950 */
2951
2952 if (brkcow) {
2953 ASSERT(svd->tr_state == SEGVN_TR_OFF);
2954 cow = !(vpprot & PROT_WRITE);
2955 } else if (svd->tr_state == SEGVN_TR_ON) {
2956 /*
2957 * If we are doing text replication COW on first touch.
2958 */
2959 ASSERT(amp != NULL);
2960 ASSERT(svd->vp != NULL);
2961 ASSERT(rw != S_WRITE);
2962 cow = (ap == NULL);
2963 } else {
2964 cow = 0;
2965 }
2966
2967 /*
2968 * If not a copy-on-write case load the translation
2969 * and return.
2970 */
2971 if (cow == 0) {
2972
2973 /*
2974 * Handle pages that have been marked for migration
2975 */
2976 if (lgrp_optimizations())
2977 page_migrate(seg, addr, &opp, 1);
2978
2979 if (IS_VMODSORT(opp->p_vnode) || enable_mbit_wa) {
2980 if (rw == S_WRITE)
2981 hat_setmod(opp);
2982 else if (rw != S_OTHER && !hat_ismod(opp))
2983 prot &= ~PROT_WRITE;
2984 }
2985
2986 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE ||
2987 (!svd->pageprot && svd->prot == (prot & vpprot)));
2988 ASSERT(amp == NULL ||
2989 svd->rcookie == HAT_INVALID_REGION_COOKIE);
2990 hat_memload_region(hat, addr, opp, prot & vpprot, hat_flag,
2991 svd->rcookie);
2992
2993 if (!(hat_flag & HAT_LOAD_LOCK))
2994 page_unlock(opp);
2995
2996 if (anon_lock) {
2997 anon_array_exit(&cookie);
2998 }
2999 return (0);
3000 }
3001
3002 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
3003
3004 hat_setref(opp);
3005
3006 ASSERT(amp != NULL && anon_lock);
3007
3008 /*
3009 * Steal the page only if it isn't a private page
3010 * since stealing a private page is not worth the effort.
3011 */
3012 if ((ap = anon_get_ptr(amp->ahp, anon_index)) == NULL)
3013 steal = 1;
3014
3015 /*
3016 * Steal the original page if the following conditions are true:
3017 *
3018 * We are low on memory, the page is not private, page is not large,
3019 * not shared, not modified, not `locked' or if we have it `locked'
3020 * (i.e., p_cowcnt == 1 and p_lckcnt == 0, which also implies
3021 * that the page is not shared) and if it doesn't have any
3022 * translations. page_struct_lock isn't needed to look at p_cowcnt
3023 * and p_lckcnt because we first get exclusive lock on page.
3024 */
3025 (void) hat_pagesync(opp, HAT_SYNC_DONTZERO | HAT_SYNC_STOPON_MOD);
3026
3027 if (stealcow && freemem < minfree && steal && opp->p_szc == 0 &&
3028 page_tryupgrade(opp) && !hat_ismod(opp) &&
3029 ((opp->p_lckcnt == 0 && opp->p_cowcnt == 0) ||
3030 (opp->p_lckcnt == 0 && opp->p_cowcnt == 1 &&
3031 vpage != NULL && VPP_ISPPLOCK(vpage)))) {
3032 /*
3033 * Check if this page has other translations
3034 * after unloading our translation.
3035 */
3036 if (hat_page_is_mapped(opp)) {
3037 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
3038 hat_unload(seg->s_as->a_hat, addr, PAGESIZE,
3039 HAT_UNLOAD);
3040 }
3041
3042 /*
3043 * hat_unload() might sync back someone else's recent
3044 * modification, so check again.
3045 */
3046 if (!hat_ismod(opp) && !hat_page_is_mapped(opp))
3047 pageflags |= STEAL_PAGE;
3048 }
3049
3050 /*
3051 * If we have a vpage pointer, see if it indicates that we have
3052 * ``locked'' the page we map -- if so, tell anon_private to
3053 * transfer the locking resource to the new page.
3054 *
3055 * See Statement at the beginning of segvn_lockop regarding
3056 * the way lockcnts/cowcnts are handled during COW.
3057 *
3058 */
3059 if (vpage != NULL && VPP_ISPPLOCK(vpage))
3060 pageflags |= LOCK_PAGE;
3061
3062 /*
3063 * Allocate a private page and perform the copy.
3064 * For MAP_NORESERVE reserve swap space now, unless this
3065 * is a cow fault on an existing anon page in which case
3066 * MAP_NORESERVE will have made advance reservations.
3067 */
3068 if ((svd->flags & MAP_NORESERVE) && (ap == NULL)) {
3069 if (anon_resv_zone(ptob(1), seg->s_as->a_proc->p_zone)) {
3070 atomic_add_long(&svd->swresv, ptob(1));
3071 atomic_add_long(&seg->s_as->a_resvsize, ptob(1));
3072 } else {
3073 page_unlock(opp);
3074 err = ENOMEM;
3075 goto out;
3076 }
3077 }
3078 oldap = ap;
3079 pp = anon_private(&ap, seg, addr, prot, opp, pageflags, svd->cred);
3080 if (pp == NULL) {
3081 err = ENOMEM; /* out of swap space */
3082 goto out;
3083 }
3084
3085 /*
3086 * If we copied away from an anonymous page, then
3087 * we are one step closer to freeing up an anon slot.
3088 *
3089 * NOTE: The original anon slot must be released while
3090 * holding the "anon_map" lock. This is necessary to prevent
3091 * other threads from obtaining a pointer to the anon slot
3092 * which may be freed if its "refcnt" is 1.
3093 */
3094 if (oldap != NULL)
3095 anon_decref(oldap);
3096
3097 (void) anon_set_ptr(amp->ahp, anon_index, ap, ANON_SLEEP);
3098
3099 /*
3100 * Handle pages that have been marked for migration
3101 */
3102 if (lgrp_optimizations())
3103 page_migrate(seg, addr, &pp, 1);
3104
3105 ASSERT(pp->p_szc == 0);
3106
3107 ASSERT(!IS_VMODSORT(pp->p_vnode));
3108 if (enable_mbit_wa) {
3109 if (rw == S_WRITE)
3110 hat_setmod(pp);
3111 else if (!hat_ismod(pp))
3112 prot &= ~PROT_WRITE;
3113 }
3114
3115 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
3116 hat_memload(hat, addr, pp, prot, hat_flag);
3117
3118 if (!(hat_flag & HAT_LOAD_LOCK))
3119 page_unlock(pp);
3120
3121 ASSERT(anon_lock);
3122 anon_array_exit(&cookie);
3123 return (0);
3124 out:
3125 if (anon_lock)
3126 anon_array_exit(&cookie);
3127
3128 if (type == F_SOFTLOCK) {
3129 atomic_dec_ulong((ulong_t *)&svd->softlockcnt);
3130 }
3131 return (FC_MAKE_ERR(err));
3132 }
3133
3134 /*
3135 * relocate a bunch of smaller targ pages into one large repl page. all targ
3136 * pages must be complete pages smaller than replacement pages.
3137 * it's assumed that no page's szc can change since they are all PAGESIZE or
3138 * complete large pages locked SHARED.
3139 */
3140 static void
segvn_relocate_pages(page_t ** targ,page_t * replacement)3141 segvn_relocate_pages(page_t **targ, page_t *replacement)
3142 {
3143 page_t *pp;
3144 pgcnt_t repl_npgs, curnpgs;
3145 pgcnt_t i;
3146 uint_t repl_szc = replacement->p_szc;
3147 page_t *first_repl = replacement;
3148 page_t *repl;
3149 spgcnt_t npgs;
3150
3151 VM_STAT_ADD(segvnvmstats.relocatepages[0]);
3152
3153 ASSERT(repl_szc != 0);
3154 npgs = repl_npgs = page_get_pagecnt(repl_szc);
3155
3156 i = 0;
3157 while (repl_npgs) {
3158 spgcnt_t nreloc;
3159 int err;
3160 ASSERT(replacement != NULL);
3161 pp = targ[i];
3162 ASSERT(pp->p_szc < repl_szc);
3163 ASSERT(PAGE_EXCL(pp));
3164 ASSERT(!PP_ISFREE(pp));
3165 curnpgs = page_get_pagecnt(pp->p_szc);
3166 if (curnpgs == 1) {
3167 VM_STAT_ADD(segvnvmstats.relocatepages[1]);
3168 repl = replacement;
3169 page_sub(&replacement, repl);
3170 ASSERT(PAGE_EXCL(repl));
3171 ASSERT(!PP_ISFREE(repl));
3172 ASSERT(repl->p_szc == repl_szc);
3173 } else {
3174 page_t *repl_savepp;
3175 int j;
3176 VM_STAT_ADD(segvnvmstats.relocatepages[2]);
3177 repl_savepp = replacement;
3178 for (j = 0; j < curnpgs; j++) {
3179 repl = replacement;
3180 page_sub(&replacement, repl);
3181 ASSERT(PAGE_EXCL(repl));
3182 ASSERT(!PP_ISFREE(repl));
3183 ASSERT(repl->p_szc == repl_szc);
3184 ASSERT(page_pptonum(targ[i + j]) ==
3185 page_pptonum(targ[i]) + j);
3186 }
3187 repl = repl_savepp;
3188 ASSERT(IS_P2ALIGNED(page_pptonum(repl), curnpgs));
3189 }
3190 err = page_relocate(&pp, &repl, 0, 1, &nreloc, NULL);
3191 if (err || nreloc != curnpgs) {
3192 panic("segvn_relocate_pages: "
3193 "page_relocate failed err=%d curnpgs=%ld "
3194 "nreloc=%ld", err, curnpgs, nreloc);
3195 }
3196 ASSERT(curnpgs <= repl_npgs);
3197 repl_npgs -= curnpgs;
3198 i += curnpgs;
3199 }
3200 ASSERT(replacement == NULL);
3201
3202 repl = first_repl;
3203 repl_npgs = npgs;
3204 for (i = 0; i < repl_npgs; i++) {
3205 ASSERT(PAGE_EXCL(repl));
3206 ASSERT(!PP_ISFREE(repl));
3207 targ[i] = repl;
3208 page_downgrade(targ[i]);
3209 repl++;
3210 }
3211 }
3212
3213 /*
3214 * Check if all pages in ppa array are complete smaller than szc pages and
3215 * their roots will still be aligned relative to their current size if the
3216 * entire ppa array is relocated into one szc page. If these conditions are
3217 * not met return 0.
3218 *
3219 * If all pages are properly aligned attempt to upgrade their locks
3220 * to exclusive mode. If it fails set *upgrdfail to 1 and return 0.
3221 * upgrdfail was set to 0 by caller.
3222 *
3223 * Return 1 if all pages are aligned and locked exclusively.
3224 *
3225 * If all pages in ppa array happen to be physically contiguous to make one
3226 * szc page and all exclusive locks are successfully obtained promote the page
3227 * size to szc and set *pszc to szc. Return 1 with pages locked shared.
3228 */
3229 static int
segvn_full_szcpages(page_t ** ppa,uint_t szc,int * upgrdfail,uint_t * pszc)3230 segvn_full_szcpages(page_t **ppa, uint_t szc, int *upgrdfail, uint_t *pszc)
3231 {
3232 page_t *pp;
3233 pfn_t pfn;
3234 pgcnt_t totnpgs = page_get_pagecnt(szc);
3235 pfn_t first_pfn;
3236 int contig = 1;
3237 pgcnt_t i;
3238 pgcnt_t j;
3239 uint_t curszc;
3240 pgcnt_t curnpgs;
3241 int root = 0;
3242
3243 ASSERT(szc > 0);
3244
3245 VM_STAT_ADD(segvnvmstats.fullszcpages[0]);
3246
3247 for (i = 0; i < totnpgs; i++) {
3248 pp = ppa[i];
3249 ASSERT(PAGE_SHARED(pp));
3250 ASSERT(!PP_ISFREE(pp));
3251 pfn = page_pptonum(pp);
3252 if (i == 0) {
3253 if (!IS_P2ALIGNED(pfn, totnpgs)) {
3254 contig = 0;
3255 } else {
3256 first_pfn = pfn;
3257 }
3258 } else if (contig && pfn != first_pfn + i) {
3259 contig = 0;
3260 }
3261 if (pp->p_szc == 0) {
3262 if (root) {
3263 VM_STAT_ADD(segvnvmstats.fullszcpages[1]);
3264 return (0);
3265 }
3266 } else if (!root) {
3267 if ((curszc = pp->p_szc) >= szc) {
3268 VM_STAT_ADD(segvnvmstats.fullszcpages[2]);
3269 return (0);
3270 }
3271 if (curszc == 0) {
3272 /*
3273 * p_szc changed means we don't have all pages
3274 * locked. return failure.
3275 */
3276 VM_STAT_ADD(segvnvmstats.fullszcpages[3]);
3277 return (0);
3278 }
3279 curnpgs = page_get_pagecnt(curszc);
3280 if (!IS_P2ALIGNED(pfn, curnpgs) ||
3281 !IS_P2ALIGNED(i, curnpgs)) {
3282 VM_STAT_ADD(segvnvmstats.fullszcpages[4]);
3283 return (0);
3284 }
3285 root = 1;
3286 } else {
3287 ASSERT(i > 0);
3288 VM_STAT_ADD(segvnvmstats.fullszcpages[5]);
3289 if (pp->p_szc != curszc) {
3290 VM_STAT_ADD(segvnvmstats.fullszcpages[6]);
3291 return (0);
3292 }
3293 if (pfn - 1 != page_pptonum(ppa[i - 1])) {
3294 panic("segvn_full_szcpages: "
3295 "large page not physically contiguous");
3296 }
3297 if (P2PHASE(pfn, curnpgs) == curnpgs - 1) {
3298 root = 0;
3299 }
3300 }
3301 }
3302
3303 for (i = 0; i < totnpgs; i++) {
3304 ASSERT(ppa[i]->p_szc < szc);
3305 if (!page_tryupgrade(ppa[i])) {
3306 for (j = 0; j < i; j++) {
3307 page_downgrade(ppa[j]);
3308 }
3309 *pszc = ppa[i]->p_szc;
3310 *upgrdfail = 1;
3311 VM_STAT_ADD(segvnvmstats.fullszcpages[7]);
3312 return (0);
3313 }
3314 }
3315
3316 /*
3317 * When a page is put a free cachelist its szc is set to 0. if file
3318 * system reclaimed pages from cachelist targ pages will be physically
3319 * contiguous with 0 p_szc. in this case just upgrade szc of targ
3320 * pages without any relocations.
3321 * To avoid any hat issues with previous small mappings
3322 * hat_pageunload() the target pages first.
3323 */
3324 if (contig) {
3325 VM_STAT_ADD(segvnvmstats.fullszcpages[8]);
3326 for (i = 0; i < totnpgs; i++) {
3327 (void) hat_pageunload(ppa[i], HAT_FORCE_PGUNLOAD);
3328 }
3329 for (i = 0; i < totnpgs; i++) {
3330 ppa[i]->p_szc = szc;
3331 }
3332 for (i = 0; i < totnpgs; i++) {
3333 ASSERT(PAGE_EXCL(ppa[i]));
3334 page_downgrade(ppa[i]);
3335 }
3336 if (pszc != NULL) {
3337 *pszc = szc;
3338 }
3339 }
3340 VM_STAT_ADD(segvnvmstats.fullszcpages[9]);
3341 return (1);
3342 }
3343
3344 /*
3345 * Create physically contiguous pages for [vp, off] - [vp, off +
3346 * page_size(szc)) range and for private segment return them in ppa array.
3347 * Pages are created either via IO or relocations.
3348 *
3349 * Return 1 on success and 0 on failure.
3350 *
3351 * If physically contiguous pages already exist for this range return 1 without
3352 * filling ppa array. Caller initializes ppa[0] as NULL to detect that ppa
3353 * array wasn't filled. In this case caller fills ppa array via VOP_GETPAGE().
3354 */
3355
3356 static int
segvn_fill_vp_pages(struct segvn_data * svd,vnode_t * vp,u_offset_t off,uint_t szc,page_t ** ppa,page_t ** ppplist,uint_t * ret_pszc,int * downsize)3357 segvn_fill_vp_pages(struct segvn_data *svd, vnode_t *vp, u_offset_t off,
3358 uint_t szc, page_t **ppa, page_t **ppplist, uint_t *ret_pszc,
3359 int *downsize)
3360
3361 {
3362 page_t *pplist = *ppplist;
3363 size_t pgsz = page_get_pagesize(szc);
3364 pgcnt_t pages = btop(pgsz);
3365 ulong_t start_off = off;
3366 u_offset_t eoff = off + pgsz;
3367 spgcnt_t nreloc;
3368 u_offset_t io_off = off;
3369 size_t io_len;
3370 page_t *io_pplist = NULL;
3371 page_t *done_pplist = NULL;
3372 pgcnt_t pgidx = 0;
3373 page_t *pp;
3374 page_t *newpp;
3375 page_t *targpp;
3376 int io_err = 0;
3377 int i;
3378 pfn_t pfn;
3379 ulong_t ppages;
3380 page_t *targ_pplist = NULL;
3381 page_t *repl_pplist = NULL;
3382 page_t *tmp_pplist;
3383 int nios = 0;
3384 uint_t pszc;
3385 struct vattr va;
3386
3387 VM_STAT_ADD(segvnvmstats.fill_vp_pages[0]);
3388
3389 ASSERT(szc != 0);
3390 ASSERT(pplist->p_szc == szc);
3391
3392 /*
3393 * downsize will be set to 1 only if we fail to lock pages. this will
3394 * allow subsequent faults to try to relocate the page again. If we
3395 * fail due to misalignment don't downsize and let the caller map the
3396 * whole region with small mappings to avoid more faults into the area
3397 * where we can't get large pages anyway.
3398 */
3399 *downsize = 0;
3400
3401 while (off < eoff) {
3402 newpp = pplist;
3403 ASSERT(newpp != NULL);
3404 ASSERT(PAGE_EXCL(newpp));
3405 ASSERT(!PP_ISFREE(newpp));
3406 /*
3407 * we pass NULL for nrelocp to page_lookup_create()
3408 * so that it doesn't relocate. We relocate here
3409 * later only after we make sure we can lock all
3410 * pages in the range we handle and they are all
3411 * aligned.
3412 */
3413 pp = page_lookup_create(vp, off, SE_SHARED, newpp, NULL, 0);
3414 ASSERT(pp != NULL);
3415 ASSERT(!PP_ISFREE(pp));
3416 ASSERT(pp->p_vnode == vp);
3417 ASSERT(pp->p_offset == off);
3418 if (pp == newpp) {
3419 VM_STAT_ADD(segvnvmstats.fill_vp_pages[1]);
3420 page_sub(&pplist, pp);
3421 ASSERT(PAGE_EXCL(pp));
3422 ASSERT(page_iolock_assert(pp));
3423 page_list_concat(&io_pplist, &pp);
3424 off += PAGESIZE;
3425 continue;
3426 }
3427 VM_STAT_ADD(segvnvmstats.fill_vp_pages[2]);
3428 pfn = page_pptonum(pp);
3429 pszc = pp->p_szc;
3430 if (pszc >= szc && targ_pplist == NULL && io_pplist == NULL &&
3431 IS_P2ALIGNED(pfn, pages)) {
3432 ASSERT(repl_pplist == NULL);
3433 ASSERT(done_pplist == NULL);
3434 ASSERT(pplist == *ppplist);
3435 page_unlock(pp);
3436 page_free_replacement_page(pplist);
3437 page_create_putback(pages);
3438 *ppplist = NULL;
3439 VM_STAT_ADD(segvnvmstats.fill_vp_pages[3]);
3440 return (1);
3441 }
3442 if (pszc >= szc) {
3443 page_unlock(pp);
3444 segvn_faultvnmpss_align_err1++;
3445 goto out;
3446 }
3447 ppages = page_get_pagecnt(pszc);
3448 if (!IS_P2ALIGNED(pfn, ppages)) {
3449 ASSERT(pszc > 0);
3450 /*
3451 * sizing down to pszc won't help.
3452 */
3453 page_unlock(pp);
3454 segvn_faultvnmpss_align_err2++;
3455 goto out;
3456 }
3457 pfn = page_pptonum(newpp);
3458 if (!IS_P2ALIGNED(pfn, ppages)) {
3459 ASSERT(pszc > 0);
3460 /*
3461 * sizing down to pszc won't help.
3462 */
3463 page_unlock(pp);
3464 segvn_faultvnmpss_align_err3++;
3465 goto out;
3466 }
3467 if (!PAGE_EXCL(pp)) {
3468 VM_STAT_ADD(segvnvmstats.fill_vp_pages[4]);
3469 page_unlock(pp);
3470 *downsize = 1;
3471 *ret_pszc = pp->p_szc;
3472 goto out;
3473 }
3474 targpp = pp;
3475 if (io_pplist != NULL) {
3476 VM_STAT_ADD(segvnvmstats.fill_vp_pages[5]);
3477 io_len = off - io_off;
3478 /*
3479 * Some file systems like NFS don't check EOF
3480 * conditions in VOP_PAGEIO(). Check it here
3481 * now that pages are locked SE_EXCL. Any file
3482 * truncation will wait until the pages are
3483 * unlocked so no need to worry that file will
3484 * be truncated after we check its size here.
3485 * XXX fix NFS to remove this check.
3486 */
3487 va.va_mask = AT_SIZE;
3488 if (VOP_GETATTR(vp, &va, ATTR_HINT, svd->cred, NULL)) {
3489 VM_STAT_ADD(segvnvmstats.fill_vp_pages[6]);
3490 page_unlock(targpp);
3491 goto out;
3492 }
3493 if (btopr(va.va_size) < btopr(io_off + io_len)) {
3494 VM_STAT_ADD(segvnvmstats.fill_vp_pages[7]);
3495 *downsize = 1;
3496 *ret_pszc = 0;
3497 page_unlock(targpp);
3498 goto out;
3499 }
3500 io_err = VOP_PAGEIO(vp, io_pplist, io_off, io_len,
3501 B_READ, svd->cred, NULL);
3502 if (io_err) {
3503 VM_STAT_ADD(segvnvmstats.fill_vp_pages[8]);
3504 page_unlock(targpp);
3505 if (io_err == EDEADLK) {
3506 segvn_vmpss_pageio_deadlk_err++;
3507 }
3508 goto out;
3509 }
3510 nios++;
3511 VM_STAT_ADD(segvnvmstats.fill_vp_pages[9]);
3512 while (io_pplist != NULL) {
3513 pp = io_pplist;
3514 page_sub(&io_pplist, pp);
3515 ASSERT(page_iolock_assert(pp));
3516 page_io_unlock(pp);
3517 pgidx = (pp->p_offset - start_off) >>
3518 PAGESHIFT;
3519 ASSERT(pgidx < pages);
3520 ppa[pgidx] = pp;
3521 page_list_concat(&done_pplist, &pp);
3522 }
3523 }
3524 pp = targpp;
3525 ASSERT(PAGE_EXCL(pp));
3526 ASSERT(pp->p_szc <= pszc);
3527 if (pszc != 0 && !group_page_trylock(pp, SE_EXCL)) {
3528 VM_STAT_ADD(segvnvmstats.fill_vp_pages[10]);
3529 page_unlock(pp);
3530 *downsize = 1;
3531 *ret_pszc = pp->p_szc;
3532 goto out;
3533 }
3534 VM_STAT_ADD(segvnvmstats.fill_vp_pages[11]);
3535 /*
3536 * page szc chould have changed before the entire group was
3537 * locked. reread page szc.
3538 */
3539 pszc = pp->p_szc;
3540 ppages = page_get_pagecnt(pszc);
3541
3542 /* link just the roots */
3543 page_list_concat(&targ_pplist, &pp);
3544 page_sub(&pplist, newpp);
3545 page_list_concat(&repl_pplist, &newpp);
3546 off += PAGESIZE;
3547 while (--ppages != 0) {
3548 newpp = pplist;
3549 page_sub(&pplist, newpp);
3550 off += PAGESIZE;
3551 }
3552 io_off = off;
3553 }
3554 if (io_pplist != NULL) {
3555 VM_STAT_ADD(segvnvmstats.fill_vp_pages[12]);
3556 io_len = eoff - io_off;
3557 va.va_mask = AT_SIZE;
3558 if (VOP_GETATTR(vp, &va, ATTR_HINT, svd->cred, NULL) != 0) {
3559 VM_STAT_ADD(segvnvmstats.fill_vp_pages[13]);
3560 goto out;
3561 }
3562 if (btopr(va.va_size) < btopr(io_off + io_len)) {
3563 VM_STAT_ADD(segvnvmstats.fill_vp_pages[14]);
3564 *downsize = 1;
3565 *ret_pszc = 0;
3566 goto out;
3567 }
3568 io_err = VOP_PAGEIO(vp, io_pplist, io_off, io_len,
3569 B_READ, svd->cred, NULL);
3570 if (io_err) {
3571 VM_STAT_ADD(segvnvmstats.fill_vp_pages[15]);
3572 if (io_err == EDEADLK) {
3573 segvn_vmpss_pageio_deadlk_err++;
3574 }
3575 goto out;
3576 }
3577 nios++;
3578 while (io_pplist != NULL) {
3579 pp = io_pplist;
3580 page_sub(&io_pplist, pp);
3581 ASSERT(page_iolock_assert(pp));
3582 page_io_unlock(pp);
3583 pgidx = (pp->p_offset - start_off) >> PAGESHIFT;
3584 ASSERT(pgidx < pages);
3585 ppa[pgidx] = pp;
3586 }
3587 }
3588 /*
3589 * we're now bound to succeed or panic.
3590 * remove pages from done_pplist. it's not needed anymore.
3591 */
3592 while (done_pplist != NULL) {
3593 pp = done_pplist;
3594 page_sub(&done_pplist, pp);
3595 }
3596 VM_STAT_ADD(segvnvmstats.fill_vp_pages[16]);
3597 ASSERT(pplist == NULL);
3598 *ppplist = NULL;
3599 while (targ_pplist != NULL) {
3600 int ret;
3601 VM_STAT_ADD(segvnvmstats.fill_vp_pages[17]);
3602 ASSERT(repl_pplist);
3603 pp = targ_pplist;
3604 page_sub(&targ_pplist, pp);
3605 pgidx = (pp->p_offset - start_off) >> PAGESHIFT;
3606 newpp = repl_pplist;
3607 page_sub(&repl_pplist, newpp);
3608 #ifdef DEBUG
3609 pfn = page_pptonum(pp);
3610 pszc = pp->p_szc;
3611 ppages = page_get_pagecnt(pszc);
3612 ASSERT(IS_P2ALIGNED(pfn, ppages));
3613 pfn = page_pptonum(newpp);
3614 ASSERT(IS_P2ALIGNED(pfn, ppages));
3615 ASSERT(P2PHASE(pfn, pages) == pgidx);
3616 #endif
3617 nreloc = 0;
3618 ret = page_relocate(&pp, &newpp, 0, 1, &nreloc, NULL);
3619 if (ret != 0 || nreloc == 0) {
3620 panic("segvn_fill_vp_pages: "
3621 "page_relocate failed");
3622 }
3623 pp = newpp;
3624 while (nreloc-- != 0) {
3625 ASSERT(PAGE_EXCL(pp));
3626 ASSERT(pp->p_vnode == vp);
3627 ASSERT(pgidx ==
3628 ((pp->p_offset - start_off) >> PAGESHIFT));
3629 ppa[pgidx++] = pp;
3630 pp++;
3631 }
3632 }
3633
3634 if (svd->type == MAP_PRIVATE) {
3635 VM_STAT_ADD(segvnvmstats.fill_vp_pages[18]);
3636 for (i = 0; i < pages; i++) {
3637 ASSERT(ppa[i] != NULL);
3638 ASSERT(PAGE_EXCL(ppa[i]));
3639 ASSERT(ppa[i]->p_vnode == vp);
3640 ASSERT(ppa[i]->p_offset ==
3641 start_off + (i << PAGESHIFT));
3642 page_downgrade(ppa[i]);
3643 }
3644 ppa[pages] = NULL;
3645 } else {
3646 VM_STAT_ADD(segvnvmstats.fill_vp_pages[19]);
3647 /*
3648 * the caller will still call VOP_GETPAGE() for shared segments
3649 * to check FS write permissions. For private segments we map
3650 * file read only anyway. so no VOP_GETPAGE is needed.
3651 */
3652 for (i = 0; i < pages; i++) {
3653 ASSERT(ppa[i] != NULL);
3654 ASSERT(PAGE_EXCL(ppa[i]));
3655 ASSERT(ppa[i]->p_vnode == vp);
3656 ASSERT(ppa[i]->p_offset ==
3657 start_off + (i << PAGESHIFT));
3658 page_unlock(ppa[i]);
3659 }
3660 ppa[0] = NULL;
3661 }
3662
3663 return (1);
3664 out:
3665 /*
3666 * Do the cleanup. Unlock target pages we didn't relocate. They are
3667 * linked on targ_pplist by root pages. reassemble unused replacement
3668 * and io pages back to pplist.
3669 */
3670 if (io_pplist != NULL) {
3671 VM_STAT_ADD(segvnvmstats.fill_vp_pages[20]);
3672 pp = io_pplist;
3673 do {
3674 ASSERT(pp->p_vnode == vp);
3675 ASSERT(pp->p_offset == io_off);
3676 ASSERT(page_iolock_assert(pp));
3677 page_io_unlock(pp);
3678 page_hashout(pp, NULL);
3679 io_off += PAGESIZE;
3680 } while ((pp = pp->p_next) != io_pplist);
3681 page_list_concat(&io_pplist, &pplist);
3682 pplist = io_pplist;
3683 }
3684 tmp_pplist = NULL;
3685 while (targ_pplist != NULL) {
3686 VM_STAT_ADD(segvnvmstats.fill_vp_pages[21]);
3687 pp = targ_pplist;
3688 ASSERT(PAGE_EXCL(pp));
3689 page_sub(&targ_pplist, pp);
3690
3691 pszc = pp->p_szc;
3692 ppages = page_get_pagecnt(pszc);
3693 ASSERT(IS_P2ALIGNED(page_pptonum(pp), ppages));
3694
3695 if (pszc != 0) {
3696 group_page_unlock(pp);
3697 }
3698 page_unlock(pp);
3699
3700 pp = repl_pplist;
3701 ASSERT(pp != NULL);
3702 ASSERT(PAGE_EXCL(pp));
3703 ASSERT(pp->p_szc == szc);
3704 page_sub(&repl_pplist, pp);
3705
3706 ASSERT(IS_P2ALIGNED(page_pptonum(pp), ppages));
3707
3708 /* relink replacement page */
3709 page_list_concat(&tmp_pplist, &pp);
3710 while (--ppages != 0) {
3711 VM_STAT_ADD(segvnvmstats.fill_vp_pages[22]);
3712 pp++;
3713 ASSERT(PAGE_EXCL(pp));
3714 ASSERT(pp->p_szc == szc);
3715 page_list_concat(&tmp_pplist, &pp);
3716 }
3717 }
3718 if (tmp_pplist != NULL) {
3719 VM_STAT_ADD(segvnvmstats.fill_vp_pages[23]);
3720 page_list_concat(&tmp_pplist, &pplist);
3721 pplist = tmp_pplist;
3722 }
3723 /*
3724 * at this point all pages are either on done_pplist or
3725 * pplist. They can't be all on done_pplist otherwise
3726 * we'd've been done.
3727 */
3728 ASSERT(pplist != NULL);
3729 if (nios != 0) {
3730 VM_STAT_ADD(segvnvmstats.fill_vp_pages[24]);
3731 pp = pplist;
3732 do {
3733 VM_STAT_ADD(segvnvmstats.fill_vp_pages[25]);
3734 ASSERT(pp->p_szc == szc);
3735 ASSERT(PAGE_EXCL(pp));
3736 ASSERT(pp->p_vnode != vp);
3737 pp->p_szc = 0;
3738 } while ((pp = pp->p_next) != pplist);
3739
3740 pp = done_pplist;
3741 do {
3742 VM_STAT_ADD(segvnvmstats.fill_vp_pages[26]);
3743 ASSERT(pp->p_szc == szc);
3744 ASSERT(PAGE_EXCL(pp));
3745 ASSERT(pp->p_vnode == vp);
3746 pp->p_szc = 0;
3747 } while ((pp = pp->p_next) != done_pplist);
3748
3749 while (pplist != NULL) {
3750 VM_STAT_ADD(segvnvmstats.fill_vp_pages[27]);
3751 pp = pplist;
3752 page_sub(&pplist, pp);
3753 page_free(pp, 0);
3754 }
3755
3756 while (done_pplist != NULL) {
3757 VM_STAT_ADD(segvnvmstats.fill_vp_pages[28]);
3758 pp = done_pplist;
3759 page_sub(&done_pplist, pp);
3760 page_unlock(pp);
3761 }
3762 *ppplist = NULL;
3763 return (0);
3764 }
3765 ASSERT(pplist == *ppplist);
3766 if (io_err) {
3767 VM_STAT_ADD(segvnvmstats.fill_vp_pages[29]);
3768 /*
3769 * don't downsize on io error.
3770 * see if vop_getpage succeeds.
3771 * pplist may still be used in this case
3772 * for relocations.
3773 */
3774 return (0);
3775 }
3776 VM_STAT_ADD(segvnvmstats.fill_vp_pages[30]);
3777 page_free_replacement_page(pplist);
3778 page_create_putback(pages);
3779 *ppplist = NULL;
3780 return (0);
3781 }
3782
3783 int segvn_anypgsz = 0;
3784
3785 #define SEGVN_RESTORE_SOFTLOCK_VP(type, pages) \
3786 if ((type) == F_SOFTLOCK) { \
3787 atomic_add_long((ulong_t *)&(svd)->softlockcnt, \
3788 -(pages)); \
3789 }
3790
3791 #define SEGVN_UPDATE_MODBITS(ppa, pages, rw, prot, vpprot) \
3792 if (IS_VMODSORT((ppa)[0]->p_vnode)) { \
3793 if ((rw) == S_WRITE) { \
3794 for (i = 0; i < (pages); i++) { \
3795 ASSERT((ppa)[i]->p_vnode == \
3796 (ppa)[0]->p_vnode); \
3797 hat_setmod((ppa)[i]); \
3798 } \
3799 } else if ((rw) != S_OTHER && \
3800 ((prot) & (vpprot) & PROT_WRITE)) { \
3801 for (i = 0; i < (pages); i++) { \
3802 ASSERT((ppa)[i]->p_vnode == \
3803 (ppa)[0]->p_vnode); \
3804 if (!hat_ismod((ppa)[i])) { \
3805 prot &= ~PROT_WRITE; \
3806 break; \
3807 } \
3808 } \
3809 } \
3810 }
3811
3812 #ifdef VM_STATS
3813
3814 #define SEGVN_VMSTAT_FLTVNPAGES(idx) \
3815 VM_STAT_ADD(segvnvmstats.fltvnpages[(idx)]);
3816
3817 #else /* VM_STATS */
3818
3819 #define SEGVN_VMSTAT_FLTVNPAGES(idx)
3820
3821 #endif
3822
3823 static faultcode_t
segvn_fault_vnodepages(struct hat * hat,struct seg * seg,caddr_t lpgaddr,caddr_t lpgeaddr,enum fault_type type,enum seg_rw rw,caddr_t addr,caddr_t eaddr,int brkcow)3824 segvn_fault_vnodepages(struct hat *hat, struct seg *seg, caddr_t lpgaddr,
3825 caddr_t lpgeaddr, enum fault_type type, enum seg_rw rw, caddr_t addr,
3826 caddr_t eaddr, int brkcow)
3827 {
3828 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
3829 struct anon_map *amp = svd->amp;
3830 uchar_t segtype = svd->type;
3831 uint_t szc = seg->s_szc;
3832 size_t pgsz = page_get_pagesize(szc);
3833 size_t maxpgsz = pgsz;
3834 pgcnt_t pages = btop(pgsz);
3835 pgcnt_t maxpages = pages;
3836 size_t ppasize = (pages + 1) * sizeof (page_t *);
3837 caddr_t a = lpgaddr;
3838 caddr_t maxlpgeaddr = lpgeaddr;
3839 u_offset_t off = svd->offset + (uintptr_t)(a - seg->s_base);
3840 ulong_t aindx = svd->anon_index + seg_page(seg, a);
3841 struct vpage *vpage = (svd->vpage != NULL) ?
3842 &svd->vpage[seg_page(seg, a)] : NULL;
3843 vnode_t *vp = svd->vp;
3844 page_t **ppa;
3845 uint_t pszc;
3846 size_t ppgsz;
3847 pgcnt_t ppages;
3848 faultcode_t err = 0;
3849 int ierr;
3850 int vop_size_err = 0;
3851 uint_t protchk, prot, vpprot;
3852 ulong_t i;
3853 int hat_flag = (type == F_SOFTLOCK) ? HAT_LOAD_LOCK : HAT_LOAD;
3854 anon_sync_obj_t an_cookie;
3855 enum seg_rw arw;
3856 int alloc_failed = 0;
3857 int adjszc_chk;
3858 struct vattr va;
3859 int xhat = 0;
3860 page_t *pplist;
3861 pfn_t pfn;
3862 int physcontig;
3863 int upgrdfail;
3864 int segvn_anypgsz_vnode = 0; /* for now map vnode with 2 page sizes */
3865 int tron = (svd->tr_state == SEGVN_TR_ON);
3866
3867 ASSERT(szc != 0);
3868 ASSERT(vp != NULL);
3869 ASSERT(brkcow == 0 || amp != NULL);
3870 ASSERT(tron == 0 || amp != NULL);
3871 ASSERT(enable_mbit_wa == 0); /* no mbit simulations with large pages */
3872 ASSERT(!(svd->flags & MAP_NORESERVE));
3873 ASSERT(type != F_SOFTUNLOCK);
3874 ASSERT(IS_P2ALIGNED(a, maxpgsz));
3875 ASSERT(amp == NULL || IS_P2ALIGNED(aindx, maxpages));
3876 ASSERT(SEGVN_LOCK_HELD(seg->s_as, &svd->lock));
3877 ASSERT(seg->s_szc < NBBY * sizeof (int));
3878 ASSERT(type != F_SOFTLOCK || lpgeaddr - a == maxpgsz);
3879 ASSERT(svd->tr_state != SEGVN_TR_INIT);
3880
3881 VM_STAT_COND_ADD(type == F_SOFTLOCK, segvnvmstats.fltvnpages[0]);
3882 VM_STAT_COND_ADD(type != F_SOFTLOCK, segvnvmstats.fltvnpages[1]);
3883
3884 if (svd->flags & MAP_TEXT) {
3885 hat_flag |= HAT_LOAD_TEXT;
3886 }
3887
3888 if (svd->pageprot) {
3889 switch (rw) {
3890 case S_READ:
3891 protchk = PROT_READ;
3892 break;
3893 case S_WRITE:
3894 protchk = PROT_WRITE;
3895 break;
3896 case S_EXEC:
3897 protchk = PROT_EXEC;
3898 break;
3899 case S_OTHER:
3900 default:
3901 protchk = PROT_READ | PROT_WRITE | PROT_EXEC;
3902 break;
3903 }
3904 } else {
3905 prot = svd->prot;
3906 /* caller has already done segment level protection check. */
3907 }
3908
3909 if (seg->s_as->a_hat != hat) {
3910 xhat = 1;
3911 }
3912
3913 if (rw == S_WRITE && segtype == MAP_PRIVATE) {
3914 SEGVN_VMSTAT_FLTVNPAGES(2);
3915 arw = S_READ;
3916 } else {
3917 arw = rw;
3918 }
3919
3920 ppa = kmem_alloc(ppasize, KM_SLEEP);
3921
3922 VM_STAT_COND_ADD(amp != NULL, segvnvmstats.fltvnpages[3]);
3923
3924 for (;;) {
3925 adjszc_chk = 0;
3926 for (; a < lpgeaddr; a += pgsz, off += pgsz, aindx += pages) {
3927 if (adjszc_chk) {
3928 while (szc < seg->s_szc) {
3929 uintptr_t e;
3930 uint_t tszc;
3931 tszc = segvn_anypgsz_vnode ? szc + 1 :
3932 seg->s_szc;
3933 ppgsz = page_get_pagesize(tszc);
3934 if (!IS_P2ALIGNED(a, ppgsz) ||
3935 ((alloc_failed >> tszc) & 0x1)) {
3936 break;
3937 }
3938 SEGVN_VMSTAT_FLTVNPAGES(4);
3939 szc = tszc;
3940 pgsz = ppgsz;
3941 pages = btop(pgsz);
3942 e = P2ROUNDUP((uintptr_t)eaddr, pgsz);
3943 lpgeaddr = (caddr_t)e;
3944 }
3945 }
3946
3947 again:
3948 if (IS_P2ALIGNED(a, maxpgsz) && amp != NULL) {
3949 ASSERT(IS_P2ALIGNED(aindx, maxpages));
3950 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
3951 anon_array_enter(amp, aindx, &an_cookie);
3952 if (anon_get_ptr(amp->ahp, aindx) != NULL) {
3953 SEGVN_VMSTAT_FLTVNPAGES(5);
3954 ASSERT(anon_pages(amp->ahp, aindx,
3955 maxpages) == maxpages);
3956 anon_array_exit(&an_cookie);
3957 ANON_LOCK_EXIT(&->a_rwlock);
3958 err = segvn_fault_anonpages(hat, seg,
3959 a, a + maxpgsz, type, rw,
3960 MAX(a, addr),
3961 MIN(a + maxpgsz, eaddr), brkcow);
3962 if (err != 0) {
3963 SEGVN_VMSTAT_FLTVNPAGES(6);
3964 goto out;
3965 }
3966 if (szc < seg->s_szc) {
3967 szc = seg->s_szc;
3968 pgsz = maxpgsz;
3969 pages = maxpages;
3970 lpgeaddr = maxlpgeaddr;
3971 }
3972 goto next;
3973 } else {
3974 ASSERT(anon_pages(amp->ahp, aindx,
3975 maxpages) == 0);
3976 SEGVN_VMSTAT_FLTVNPAGES(7);
3977 anon_array_exit(&an_cookie);
3978 ANON_LOCK_EXIT(&->a_rwlock);
3979 }
3980 }
3981 ASSERT(!brkcow || IS_P2ALIGNED(a, maxpgsz));
3982 ASSERT(!tron || IS_P2ALIGNED(a, maxpgsz));
3983
3984 if (svd->pageprot != 0 && IS_P2ALIGNED(a, maxpgsz)) {
3985 ASSERT(vpage != NULL);
3986 prot = VPP_PROT(vpage);
3987 ASSERT(sameprot(seg, a, maxpgsz));
3988 if ((prot & protchk) == 0) {
3989 SEGVN_VMSTAT_FLTVNPAGES(8);
3990 err = FC_PROT;
3991 goto out;
3992 }
3993 }
3994 if (type == F_SOFTLOCK) {
3995 atomic_add_long((ulong_t *)&svd->softlockcnt,
3996 pages);
3997 }
3998
3999 pplist = NULL;
4000 physcontig = 0;
4001 ppa[0] = NULL;
4002 if (!brkcow && !tron && szc &&
4003 !page_exists_physcontig(vp, off, szc,
4004 segtype == MAP_PRIVATE ? ppa : NULL)) {
4005 SEGVN_VMSTAT_FLTVNPAGES(9);
4006 if (page_alloc_pages(vp, seg, a, &pplist, NULL,
4007 szc, 0, 0) && type != F_SOFTLOCK) {
4008 SEGVN_VMSTAT_FLTVNPAGES(10);
4009 pszc = 0;
4010 ierr = -1;
4011 alloc_failed |= (1 << szc);
4012 break;
4013 }
4014 if (pplist != NULL &&
4015 vp->v_mpssdata == SEGVN_PAGEIO) {
4016 int downsize;
4017 SEGVN_VMSTAT_FLTVNPAGES(11);
4018 physcontig = segvn_fill_vp_pages(svd,
4019 vp, off, szc, ppa, &pplist,
4020 &pszc, &downsize);
4021 ASSERT(!physcontig || pplist == NULL);
4022 if (!physcontig && downsize &&
4023 type != F_SOFTLOCK) {
4024 ASSERT(pplist == NULL);
4025 SEGVN_VMSTAT_FLTVNPAGES(12);
4026 ierr = -1;
4027 break;
4028 }
4029 ASSERT(!physcontig ||
4030 segtype == MAP_PRIVATE ||
4031 ppa[0] == NULL);
4032 if (physcontig && ppa[0] == NULL) {
4033 physcontig = 0;
4034 }
4035 }
4036 } else if (!brkcow && !tron && szc && ppa[0] != NULL) {
4037 SEGVN_VMSTAT_FLTVNPAGES(13);
4038 ASSERT(segtype == MAP_PRIVATE);
4039 physcontig = 1;
4040 }
4041
4042 if (!physcontig) {
4043 SEGVN_VMSTAT_FLTVNPAGES(14);
4044 ppa[0] = NULL;
4045 ierr = VOP_GETPAGE(vp, (offset_t)off, pgsz,
4046 &vpprot, ppa, pgsz, seg, a, arw,
4047 svd->cred, NULL);
4048 #ifdef DEBUG
4049 if (ierr == 0) {
4050 for (i = 0; i < pages; i++) {
4051 ASSERT(PAGE_LOCKED(ppa[i]));
4052 ASSERT(!PP_ISFREE(ppa[i]));
4053 ASSERT(ppa[i]->p_vnode == vp);
4054 ASSERT(ppa[i]->p_offset ==
4055 off + (i << PAGESHIFT));
4056 }
4057 }
4058 #endif /* DEBUG */
4059 if (segtype == MAP_PRIVATE) {
4060 SEGVN_VMSTAT_FLTVNPAGES(15);
4061 vpprot &= ~PROT_WRITE;
4062 }
4063 } else {
4064 ASSERT(segtype == MAP_PRIVATE);
4065 SEGVN_VMSTAT_FLTVNPAGES(16);
4066 vpprot = PROT_ALL & ~PROT_WRITE;
4067 ierr = 0;
4068 }
4069
4070 if (ierr != 0) {
4071 SEGVN_VMSTAT_FLTVNPAGES(17);
4072 if (pplist != NULL) {
4073 SEGVN_VMSTAT_FLTVNPAGES(18);
4074 page_free_replacement_page(pplist);
4075 page_create_putback(pages);
4076 }
4077 SEGVN_RESTORE_SOFTLOCK_VP(type, pages);
4078 if (a + pgsz <= eaddr) {
4079 SEGVN_VMSTAT_FLTVNPAGES(19);
4080 err = FC_MAKE_ERR(ierr);
4081 goto out;
4082 }
4083 va.va_mask = AT_SIZE;
4084 if (VOP_GETATTR(vp, &va, 0, svd->cred, NULL)) {
4085 SEGVN_VMSTAT_FLTVNPAGES(20);
4086 err = FC_MAKE_ERR(EIO);
4087 goto out;
4088 }
4089 if (btopr(va.va_size) >= btopr(off + pgsz)) {
4090 SEGVN_VMSTAT_FLTVNPAGES(21);
4091 err = FC_MAKE_ERR(ierr);
4092 goto out;
4093 }
4094 if (btopr(va.va_size) <
4095 btopr(off + (eaddr - a))) {
4096 SEGVN_VMSTAT_FLTVNPAGES(22);
4097 err = FC_MAKE_ERR(ierr);
4098 goto out;
4099 }
4100 if (brkcow || tron || type == F_SOFTLOCK) {
4101 /* can't reduce map area */
4102 SEGVN_VMSTAT_FLTVNPAGES(23);
4103 vop_size_err = 1;
4104 goto out;
4105 }
4106 SEGVN_VMSTAT_FLTVNPAGES(24);
4107 ASSERT(szc != 0);
4108 pszc = 0;
4109 ierr = -1;
4110 break;
4111 }
4112
4113 if (amp != NULL) {
4114 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
4115 anon_array_enter(amp, aindx, &an_cookie);
4116 }
4117 if (amp != NULL &&
4118 anon_get_ptr(amp->ahp, aindx) != NULL) {
4119 ulong_t taindx = P2ALIGN(aindx, maxpages);
4120
4121 SEGVN_VMSTAT_FLTVNPAGES(25);
4122 ASSERT(anon_pages(amp->ahp, taindx,
4123 maxpages) == maxpages);
4124 for (i = 0; i < pages; i++) {
4125 page_unlock(ppa[i]);
4126 }
4127 anon_array_exit(&an_cookie);
4128 ANON_LOCK_EXIT(&->a_rwlock);
4129 if (pplist != NULL) {
4130 page_free_replacement_page(pplist);
4131 page_create_putback(pages);
4132 }
4133 SEGVN_RESTORE_SOFTLOCK_VP(type, pages);
4134 if (szc < seg->s_szc) {
4135 SEGVN_VMSTAT_FLTVNPAGES(26);
4136 /*
4137 * For private segments SOFTLOCK
4138 * either always breaks cow (any rw
4139 * type except S_READ_NOCOW) or
4140 * address space is locked as writer
4141 * (S_READ_NOCOW case) and anon slots
4142 * can't show up on second check.
4143 * Therefore if we are here for
4144 * SOFTLOCK case it must be a cow
4145 * break but cow break never reduces
4146 * szc. text replication (tron) in
4147 * this case works as cow break.
4148 * Thus the assert below.
4149 */
4150 ASSERT(!brkcow && !tron &&
4151 type != F_SOFTLOCK);
4152 pszc = seg->s_szc;
4153 ierr = -2;
4154 break;
4155 }
4156 ASSERT(IS_P2ALIGNED(a, maxpgsz));
4157 goto again;
4158 }
4159 #ifdef DEBUG
4160 if (amp != NULL) {
4161 ulong_t taindx = P2ALIGN(aindx, maxpages);
4162 ASSERT(!anon_pages(amp->ahp, taindx, maxpages));
4163 }
4164 #endif /* DEBUG */
4165
4166 if (brkcow || tron) {
4167 ASSERT(amp != NULL);
4168 ASSERT(pplist == NULL);
4169 ASSERT(szc == seg->s_szc);
4170 ASSERT(IS_P2ALIGNED(a, maxpgsz));
4171 ASSERT(IS_P2ALIGNED(aindx, maxpages));
4172 SEGVN_VMSTAT_FLTVNPAGES(27);
4173 ierr = anon_map_privatepages(amp, aindx, szc,
4174 seg, a, prot, ppa, vpage, segvn_anypgsz,
4175 tron ? PG_LOCAL : 0, svd->cred);
4176 if (ierr != 0) {
4177 SEGVN_VMSTAT_FLTVNPAGES(28);
4178 anon_array_exit(&an_cookie);
4179 ANON_LOCK_EXIT(&->a_rwlock);
4180 SEGVN_RESTORE_SOFTLOCK_VP(type, pages);
4181 err = FC_MAKE_ERR(ierr);
4182 goto out;
4183 }
4184
4185 ASSERT(!IS_VMODSORT(ppa[0]->p_vnode));
4186 /*
4187 * p_szc can't be changed for locked
4188 * swapfs pages.
4189 */
4190 ASSERT(svd->rcookie ==
4191 HAT_INVALID_REGION_COOKIE);
4192 hat_memload_array(hat, a, pgsz, ppa, prot,
4193 hat_flag);
4194
4195 if (!(hat_flag & HAT_LOAD_LOCK)) {
4196 SEGVN_VMSTAT_FLTVNPAGES(29);
4197 for (i = 0; i < pages; i++) {
4198 page_unlock(ppa[i]);
4199 }
4200 }
4201 anon_array_exit(&an_cookie);
4202 ANON_LOCK_EXIT(&->a_rwlock);
4203 goto next;
4204 }
4205
4206 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE ||
4207 (!svd->pageprot && svd->prot == (prot & vpprot)));
4208
4209 pfn = page_pptonum(ppa[0]);
4210 /*
4211 * hat_page_demote() needs an SE_EXCL lock on one of
4212 * constituent page_t's and it decreases root's p_szc
4213 * last. This means if root's p_szc is equal szc and
4214 * all its constituent pages are locked
4215 * hat_page_demote() that could have changed p_szc to
4216 * szc is already done and no new have page_demote()
4217 * can start for this large page.
4218 */
4219
4220 /*
4221 * we need to make sure same mapping size is used for
4222 * the same address range if there's a possibility the
4223 * adddress is already mapped because hat layer panics
4224 * when translation is loaded for the range already
4225 * mapped with a different page size. We achieve it
4226 * by always using largest page size possible subject
4227 * to the constraints of page size, segment page size
4228 * and page alignment. Since mappings are invalidated
4229 * when those constraints change and make it
4230 * impossible to use previously used mapping size no
4231 * mapping size conflicts should happen.
4232 */
4233
4234 chkszc:
4235 if ((pszc = ppa[0]->p_szc) == szc &&
4236 IS_P2ALIGNED(pfn, pages)) {
4237
4238 SEGVN_VMSTAT_FLTVNPAGES(30);
4239 #ifdef DEBUG
4240 for (i = 0; i < pages; i++) {
4241 ASSERT(PAGE_LOCKED(ppa[i]));
4242 ASSERT(!PP_ISFREE(ppa[i]));
4243 ASSERT(page_pptonum(ppa[i]) ==
4244 pfn + i);
4245 ASSERT(ppa[i]->p_szc == szc);
4246 ASSERT(ppa[i]->p_vnode == vp);
4247 ASSERT(ppa[i]->p_offset ==
4248 off + (i << PAGESHIFT));
4249 }
4250 #endif /* DEBUG */
4251 /*
4252 * All pages are of szc we need and they are
4253 * all locked so they can't change szc. load
4254 * translations.
4255 *
4256 * if page got promoted since last check
4257 * we don't need pplist.
4258 */
4259 if (pplist != NULL) {
4260 page_free_replacement_page(pplist);
4261 page_create_putback(pages);
4262 }
4263 if (PP_ISMIGRATE(ppa[0])) {
4264 page_migrate(seg, a, ppa, pages);
4265 }
4266 SEGVN_UPDATE_MODBITS(ppa, pages, rw,
4267 prot, vpprot);
4268 if (!xhat) {
4269 hat_memload_array_region(hat, a, pgsz,
4270 ppa, prot & vpprot, hat_flag,
4271 svd->rcookie);
4272 } else {
4273 /*
4274 * avoid large xhat mappings to FS
4275 * pages so that hat_page_demote()
4276 * doesn't need to check for xhat
4277 * large mappings.
4278 * Don't use regions with xhats.
4279 */
4280 for (i = 0; i < pages; i++) {
4281 hat_memload(hat,
4282 a + (i << PAGESHIFT),
4283 ppa[i], prot & vpprot,
4284 hat_flag);
4285 }
4286 }
4287
4288 if (!(hat_flag & HAT_LOAD_LOCK)) {
4289 for (i = 0; i < pages; i++) {
4290 page_unlock(ppa[i]);
4291 }
4292 }
4293 if (amp != NULL) {
4294 anon_array_exit(&an_cookie);
4295 ANON_LOCK_EXIT(&->a_rwlock);
4296 }
4297 goto next;
4298 }
4299
4300 /*
4301 * See if upsize is possible.
4302 */
4303 if (pszc > szc && szc < seg->s_szc &&
4304 (segvn_anypgsz_vnode || pszc >= seg->s_szc)) {
4305 pgcnt_t aphase;
4306 uint_t pszc1 = MIN(pszc, seg->s_szc);
4307 ppgsz = page_get_pagesize(pszc1);
4308 ppages = btop(ppgsz);
4309 aphase = btop(P2PHASE((uintptr_t)a, ppgsz));
4310
4311 ASSERT(type != F_SOFTLOCK);
4312
4313 SEGVN_VMSTAT_FLTVNPAGES(31);
4314 if (aphase != P2PHASE(pfn, ppages)) {
4315 segvn_faultvnmpss_align_err4++;
4316 } else {
4317 SEGVN_VMSTAT_FLTVNPAGES(32);
4318 if (pplist != NULL) {
4319 page_t *pl = pplist;
4320 page_free_replacement_page(pl);
4321 page_create_putback(pages);
4322 }
4323 for (i = 0; i < pages; i++) {
4324 page_unlock(ppa[i]);
4325 }
4326 if (amp != NULL) {
4327 anon_array_exit(&an_cookie);
4328 ANON_LOCK_EXIT(&->a_rwlock);
4329 }
4330 pszc = pszc1;
4331 ierr = -2;
4332 break;
4333 }
4334 }
4335
4336 /*
4337 * check if we should use smallest mapping size.
4338 */
4339 upgrdfail = 0;
4340 if (szc == 0 || xhat ||
4341 (pszc >= szc &&
4342 !IS_P2ALIGNED(pfn, pages)) ||
4343 (pszc < szc &&
4344 !segvn_full_szcpages(ppa, szc, &upgrdfail,
4345 &pszc))) {
4346
4347 if (upgrdfail && type != F_SOFTLOCK) {
4348 /*
4349 * segvn_full_szcpages failed to lock
4350 * all pages EXCL. Size down.
4351 */
4352 ASSERT(pszc < szc);
4353
4354 SEGVN_VMSTAT_FLTVNPAGES(33);
4355
4356 if (pplist != NULL) {
4357 page_t *pl = pplist;
4358 page_free_replacement_page(pl);
4359 page_create_putback(pages);
4360 }
4361
4362 for (i = 0; i < pages; i++) {
4363 page_unlock(ppa[i]);
4364 }
4365 if (amp != NULL) {
4366 anon_array_exit(&an_cookie);
4367 ANON_LOCK_EXIT(&->a_rwlock);
4368 }
4369 ierr = -1;
4370 break;
4371 }
4372 if (szc != 0 && !xhat && !upgrdfail) {
4373 segvn_faultvnmpss_align_err5++;
4374 }
4375 SEGVN_VMSTAT_FLTVNPAGES(34);
4376 if (pplist != NULL) {
4377 page_free_replacement_page(pplist);
4378 page_create_putback(pages);
4379 }
4380 SEGVN_UPDATE_MODBITS(ppa, pages, rw,
4381 prot, vpprot);
4382 if (upgrdfail && segvn_anypgsz_vnode) {
4383 /* SOFTLOCK case */
4384 hat_memload_array_region(hat, a, pgsz,
4385 ppa, prot & vpprot, hat_flag,
4386 svd->rcookie);
4387 } else {
4388 for (i = 0; i < pages; i++) {
4389 hat_memload_region(hat,
4390 a + (i << PAGESHIFT),
4391 ppa[i], prot & vpprot,
4392 hat_flag, svd->rcookie);
4393 }
4394 }
4395 if (!(hat_flag & HAT_LOAD_LOCK)) {
4396 for (i = 0; i < pages; i++) {
4397 page_unlock(ppa[i]);
4398 }
4399 }
4400 if (amp != NULL) {
4401 anon_array_exit(&an_cookie);
4402 ANON_LOCK_EXIT(&->a_rwlock);
4403 }
4404 goto next;
4405 }
4406
4407 if (pszc == szc) {
4408 /*
4409 * segvn_full_szcpages() upgraded pages szc.
4410 */
4411 ASSERT(pszc == ppa[0]->p_szc);
4412 ASSERT(IS_P2ALIGNED(pfn, pages));
4413 goto chkszc;
4414 }
4415
4416 if (pszc > szc) {
4417 kmutex_t *szcmtx;
4418 SEGVN_VMSTAT_FLTVNPAGES(35);
4419 /*
4420 * p_szc of ppa[0] can change since we haven't
4421 * locked all constituent pages. Call
4422 * page_lock_szc() to prevent szc changes.
4423 * This should be a rare case that happens when
4424 * multiple segments use a different page size
4425 * to map the same file offsets.
4426 */
4427 szcmtx = page_szc_lock(ppa[0]);
4428 pszc = ppa[0]->p_szc;
4429 ASSERT(szcmtx != NULL || pszc == 0);
4430 ASSERT(ppa[0]->p_szc <= pszc);
4431 if (pszc <= szc) {
4432 SEGVN_VMSTAT_FLTVNPAGES(36);
4433 if (szcmtx != NULL) {
4434 mutex_exit(szcmtx);
4435 }
4436 goto chkszc;
4437 }
4438 if (pplist != NULL) {
4439 /*
4440 * page got promoted since last check.
4441 * we don't need preaalocated large
4442 * page.
4443 */
4444 SEGVN_VMSTAT_FLTVNPAGES(37);
4445 page_free_replacement_page(pplist);
4446 page_create_putback(pages);
4447 }
4448 SEGVN_UPDATE_MODBITS(ppa, pages, rw,
4449 prot, vpprot);
4450 hat_memload_array_region(hat, a, pgsz, ppa,
4451 prot & vpprot, hat_flag, svd->rcookie);
4452 mutex_exit(szcmtx);
4453 if (!(hat_flag & HAT_LOAD_LOCK)) {
4454 for (i = 0; i < pages; i++) {
4455 page_unlock(ppa[i]);
4456 }
4457 }
4458 if (amp != NULL) {
4459 anon_array_exit(&an_cookie);
4460 ANON_LOCK_EXIT(&->a_rwlock);
4461 }
4462 goto next;
4463 }
4464
4465 /*
4466 * if page got demoted since last check
4467 * we could have not allocated larger page.
4468 * allocate now.
4469 */
4470 if (pplist == NULL &&
4471 page_alloc_pages(vp, seg, a, &pplist, NULL,
4472 szc, 0, 0) && type != F_SOFTLOCK) {
4473 SEGVN_VMSTAT_FLTVNPAGES(38);
4474 for (i = 0; i < pages; i++) {
4475 page_unlock(ppa[i]);
4476 }
4477 if (amp != NULL) {
4478 anon_array_exit(&an_cookie);
4479 ANON_LOCK_EXIT(&->a_rwlock);
4480 }
4481 ierr = -1;
4482 alloc_failed |= (1 << szc);
4483 break;
4484 }
4485
4486 SEGVN_VMSTAT_FLTVNPAGES(39);
4487
4488 if (pplist != NULL) {
4489 segvn_relocate_pages(ppa, pplist);
4490 #ifdef DEBUG
4491 } else {
4492 ASSERT(type == F_SOFTLOCK);
4493 SEGVN_VMSTAT_FLTVNPAGES(40);
4494 #endif /* DEBUG */
4495 }
4496
4497 SEGVN_UPDATE_MODBITS(ppa, pages, rw, prot, vpprot);
4498
4499 if (pplist == NULL && segvn_anypgsz_vnode == 0) {
4500 ASSERT(type == F_SOFTLOCK);
4501 for (i = 0; i < pages; i++) {
4502 ASSERT(ppa[i]->p_szc < szc);
4503 hat_memload_region(hat,
4504 a + (i << PAGESHIFT),
4505 ppa[i], prot & vpprot, hat_flag,
4506 svd->rcookie);
4507 }
4508 } else {
4509 ASSERT(pplist != NULL || type == F_SOFTLOCK);
4510 hat_memload_array_region(hat, a, pgsz, ppa,
4511 prot & vpprot, hat_flag, svd->rcookie);
4512 }
4513 if (!(hat_flag & HAT_LOAD_LOCK)) {
4514 for (i = 0; i < pages; i++) {
4515 ASSERT(PAGE_SHARED(ppa[i]));
4516 page_unlock(ppa[i]);
4517 }
4518 }
4519 if (amp != NULL) {
4520 anon_array_exit(&an_cookie);
4521 ANON_LOCK_EXIT(&->a_rwlock);
4522 }
4523
4524 next:
4525 if (vpage != NULL) {
4526 vpage += pages;
4527 }
4528 adjszc_chk = 1;
4529 }
4530 if (a == lpgeaddr)
4531 break;
4532 ASSERT(a < lpgeaddr);
4533
4534 ASSERT(!brkcow && !tron && type != F_SOFTLOCK);
4535
4536 /*
4537 * ierr == -1 means we failed to map with a large page.
4538 * (either due to allocation/relocation failures or
4539 * misalignment with other mappings to this file.
4540 *
4541 * ierr == -2 means some other thread allocated a large page
4542 * after we gave up tp map with a large page. retry with
4543 * larger mapping.
4544 */
4545 ASSERT(ierr == -1 || ierr == -2);
4546 ASSERT(ierr == -2 || szc != 0);
4547 ASSERT(ierr == -1 || szc < seg->s_szc);
4548 if (ierr == -2) {
4549 SEGVN_VMSTAT_FLTVNPAGES(41);
4550 ASSERT(pszc > szc && pszc <= seg->s_szc);
4551 szc = pszc;
4552 } else if (segvn_anypgsz_vnode) {
4553 SEGVN_VMSTAT_FLTVNPAGES(42);
4554 szc--;
4555 } else {
4556 SEGVN_VMSTAT_FLTVNPAGES(43);
4557 ASSERT(pszc < szc);
4558 /*
4559 * other process created pszc large page.
4560 * but we still have to drop to 0 szc.
4561 */
4562 szc = 0;
4563 }
4564
4565 pgsz = page_get_pagesize(szc);
4566 pages = btop(pgsz);
4567 if (ierr == -2) {
4568 /*
4569 * Size up case. Note lpgaddr may only be needed for
4570 * softlock case so we don't adjust it here.
4571 */
4572 a = (caddr_t)P2ALIGN((uintptr_t)a, pgsz);
4573 ASSERT(a >= lpgaddr);
4574 lpgeaddr = (caddr_t)P2ROUNDUP((uintptr_t)eaddr, pgsz);
4575 off = svd->offset + (uintptr_t)(a - seg->s_base);
4576 aindx = svd->anon_index + seg_page(seg, a);
4577 vpage = (svd->vpage != NULL) ?
4578 &svd->vpage[seg_page(seg, a)] : NULL;
4579 } else {
4580 /*
4581 * Size down case. Note lpgaddr may only be needed for
4582 * softlock case so we don't adjust it here.
4583 */
4584 ASSERT(IS_P2ALIGNED(a, pgsz));
4585 ASSERT(IS_P2ALIGNED(lpgeaddr, pgsz));
4586 lpgeaddr = (caddr_t)P2ROUNDUP((uintptr_t)eaddr, pgsz);
4587 ASSERT(a < lpgeaddr);
4588 if (a < addr) {
4589 SEGVN_VMSTAT_FLTVNPAGES(44);
4590 /*
4591 * The beginning of the large page region can
4592 * be pulled to the right to make a smaller
4593 * region. We haven't yet faulted a single
4594 * page.
4595 */
4596 a = (caddr_t)P2ALIGN((uintptr_t)addr, pgsz);
4597 ASSERT(a >= lpgaddr);
4598 off = svd->offset +
4599 (uintptr_t)(a - seg->s_base);
4600 aindx = svd->anon_index + seg_page(seg, a);
4601 vpage = (svd->vpage != NULL) ?
4602 &svd->vpage[seg_page(seg, a)] : NULL;
4603 }
4604 }
4605 }
4606 out:
4607 kmem_free(ppa, ppasize);
4608 if (!err && !vop_size_err) {
4609 SEGVN_VMSTAT_FLTVNPAGES(45);
4610 return (0);
4611 }
4612 if (type == F_SOFTLOCK && a > lpgaddr) {
4613 SEGVN_VMSTAT_FLTVNPAGES(46);
4614 segvn_softunlock(seg, lpgaddr, a - lpgaddr, S_OTHER);
4615 }
4616 if (!vop_size_err) {
4617 SEGVN_VMSTAT_FLTVNPAGES(47);
4618 return (err);
4619 }
4620 ASSERT(brkcow || tron || type == F_SOFTLOCK);
4621 /*
4622 * Large page end is mapped beyond the end of file and it's a cow
4623 * fault (can be a text replication induced cow) or softlock so we can't
4624 * reduce the map area. For now just demote the segment. This should
4625 * really only happen if the end of the file changed after the mapping
4626 * was established since when large page segments are created we make
4627 * sure they don't extend beyond the end of the file.
4628 */
4629 SEGVN_VMSTAT_FLTVNPAGES(48);
4630
4631 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
4632 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
4633 err = 0;
4634 if (seg->s_szc != 0) {
4635 segvn_fltvnpages_clrszc_cnt++;
4636 ASSERT(svd->softlockcnt == 0);
4637 err = segvn_clrszc(seg);
4638 if (err != 0) {
4639 segvn_fltvnpages_clrszc_err++;
4640 }
4641 }
4642 ASSERT(err || seg->s_szc == 0);
4643 SEGVN_LOCK_DOWNGRADE(seg->s_as, &svd->lock);
4644 /* segvn_fault will do its job as if szc had been zero to begin with */
4645 return (err == 0 ? IE_RETRY : FC_MAKE_ERR(err));
4646 }
4647
4648 /*
4649 * This routine will attempt to fault in one large page.
4650 * it will use smaller pages if that fails.
4651 * It should only be called for pure anonymous segments.
4652 */
4653 static faultcode_t
segvn_fault_anonpages(struct hat * hat,struct seg * seg,caddr_t lpgaddr,caddr_t lpgeaddr,enum fault_type type,enum seg_rw rw,caddr_t addr,caddr_t eaddr,int brkcow)4654 segvn_fault_anonpages(struct hat *hat, struct seg *seg, caddr_t lpgaddr,
4655 caddr_t lpgeaddr, enum fault_type type, enum seg_rw rw, caddr_t addr,
4656 caddr_t eaddr, int brkcow)
4657 {
4658 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
4659 struct anon_map *amp = svd->amp;
4660 uchar_t segtype = svd->type;
4661 uint_t szc = seg->s_szc;
4662 size_t pgsz = page_get_pagesize(szc);
4663 size_t maxpgsz = pgsz;
4664 pgcnt_t pages = btop(pgsz);
4665 uint_t ppaszc = szc;
4666 caddr_t a = lpgaddr;
4667 ulong_t aindx = svd->anon_index + seg_page(seg, a);
4668 struct vpage *vpage = (svd->vpage != NULL) ?
4669 &svd->vpage[seg_page(seg, a)] : NULL;
4670 page_t **ppa;
4671 uint_t ppa_szc;
4672 faultcode_t err;
4673 int ierr;
4674 uint_t protchk, prot, vpprot;
4675 ulong_t i;
4676 int hat_flag = (type == F_SOFTLOCK) ? HAT_LOAD_LOCK : HAT_LOAD;
4677 anon_sync_obj_t cookie;
4678 int adjszc_chk;
4679 int pgflags = (svd->tr_state == SEGVN_TR_ON) ? PG_LOCAL : 0;
4680
4681 ASSERT(szc != 0);
4682 ASSERT(amp != NULL);
4683 ASSERT(enable_mbit_wa == 0); /* no mbit simulations with large pages */
4684 ASSERT(!(svd->flags & MAP_NORESERVE));
4685 ASSERT(type != F_SOFTUNLOCK);
4686 ASSERT(IS_P2ALIGNED(a, maxpgsz));
4687 ASSERT(!brkcow || svd->tr_state == SEGVN_TR_OFF);
4688 ASSERT(svd->tr_state != SEGVN_TR_INIT);
4689
4690 ASSERT(SEGVN_LOCK_HELD(seg->s_as, &svd->lock));
4691
4692 VM_STAT_COND_ADD(type == F_SOFTLOCK, segvnvmstats.fltanpages[0]);
4693 VM_STAT_COND_ADD(type != F_SOFTLOCK, segvnvmstats.fltanpages[1]);
4694
4695 if (svd->flags & MAP_TEXT) {
4696 hat_flag |= HAT_LOAD_TEXT;
4697 }
4698
4699 if (svd->pageprot) {
4700 switch (rw) {
4701 case S_READ:
4702 protchk = PROT_READ;
4703 break;
4704 case S_WRITE:
4705 protchk = PROT_WRITE;
4706 break;
4707 case S_EXEC:
4708 protchk = PROT_EXEC;
4709 break;
4710 case S_OTHER:
4711 default:
4712 protchk = PROT_READ | PROT_WRITE | PROT_EXEC;
4713 break;
4714 }
4715 VM_STAT_ADD(segvnvmstats.fltanpages[2]);
4716 } else {
4717 prot = svd->prot;
4718 /* caller has already done segment level protection check. */
4719 }
4720
4721 ppa = kmem_cache_alloc(segvn_szc_cache[ppaszc], KM_SLEEP);
4722 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
4723 for (;;) {
4724 adjszc_chk = 0;
4725 for (; a < lpgeaddr; a += pgsz, aindx += pages) {
4726 if (svd->pageprot != 0 && IS_P2ALIGNED(a, maxpgsz)) {
4727 VM_STAT_ADD(segvnvmstats.fltanpages[3]);
4728 ASSERT(vpage != NULL);
4729 prot = VPP_PROT(vpage);
4730 ASSERT(sameprot(seg, a, maxpgsz));
4731 if ((prot & protchk) == 0) {
4732 err = FC_PROT;
4733 goto error;
4734 }
4735 }
4736 if (adjszc_chk && IS_P2ALIGNED(a, maxpgsz) &&
4737 pgsz < maxpgsz) {
4738 ASSERT(a > lpgaddr);
4739 szc = seg->s_szc;
4740 pgsz = maxpgsz;
4741 pages = btop(pgsz);
4742 ASSERT(IS_P2ALIGNED(aindx, pages));
4743 lpgeaddr = (caddr_t)P2ROUNDUP((uintptr_t)eaddr,
4744 pgsz);
4745 }
4746 if (type == F_SOFTLOCK) {
4747 atomic_add_long((ulong_t *)&svd->softlockcnt,
4748 pages);
4749 }
4750 anon_array_enter(amp, aindx, &cookie);
4751 ppa_szc = (uint_t)-1;
4752 ierr = anon_map_getpages(amp, aindx, szc, seg, a,
4753 prot, &vpprot, ppa, &ppa_szc, vpage, rw, brkcow,
4754 segvn_anypgsz, pgflags, svd->cred);
4755 if (ierr != 0) {
4756 anon_array_exit(&cookie);
4757 VM_STAT_ADD(segvnvmstats.fltanpages[4]);
4758 if (type == F_SOFTLOCK) {
4759 atomic_add_long(
4760 (ulong_t *)&svd->softlockcnt,
4761 -pages);
4762 }
4763 if (ierr > 0) {
4764 VM_STAT_ADD(segvnvmstats.fltanpages[6]);
4765 err = FC_MAKE_ERR(ierr);
4766 goto error;
4767 }
4768 break;
4769 }
4770
4771 ASSERT(!IS_VMODSORT(ppa[0]->p_vnode));
4772
4773 ASSERT(segtype == MAP_SHARED ||
4774 ppa[0]->p_szc <= szc);
4775 ASSERT(segtype == MAP_PRIVATE ||
4776 ppa[0]->p_szc >= szc);
4777
4778 /*
4779 * Handle pages that have been marked for migration
4780 */
4781 if (lgrp_optimizations())
4782 page_migrate(seg, a, ppa, pages);
4783
4784 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
4785
4786 if (segtype == MAP_SHARED) {
4787 vpprot |= PROT_WRITE;
4788 }
4789
4790 hat_memload_array(hat, a, pgsz, ppa,
4791 prot & vpprot, hat_flag);
4792
4793 if (hat_flag & HAT_LOAD_LOCK) {
4794 VM_STAT_ADD(segvnvmstats.fltanpages[7]);
4795 } else {
4796 VM_STAT_ADD(segvnvmstats.fltanpages[8]);
4797 for (i = 0; i < pages; i++)
4798 page_unlock(ppa[i]);
4799 }
4800 if (vpage != NULL)
4801 vpage += pages;
4802
4803 anon_array_exit(&cookie);
4804 adjszc_chk = 1;
4805 }
4806 if (a == lpgeaddr)
4807 break;
4808 ASSERT(a < lpgeaddr);
4809 /*
4810 * ierr == -1 means we failed to allocate a large page.
4811 * so do a size down operation.
4812 *
4813 * ierr == -2 means some other process that privately shares
4814 * pages with this process has allocated a larger page and we
4815 * need to retry with larger pages. So do a size up
4816 * operation. This relies on the fact that large pages are
4817 * never partially shared i.e. if we share any constituent
4818 * page of a large page with another process we must share the
4819 * entire large page. Note this cannot happen for SOFTLOCK
4820 * case, unless current address (a) is at the beginning of the
4821 * next page size boundary because the other process couldn't
4822 * have relocated locked pages.
4823 */
4824 ASSERT(ierr == -1 || ierr == -2);
4825
4826 if (segvn_anypgsz) {
4827 ASSERT(ierr == -2 || szc != 0);
4828 ASSERT(ierr == -1 || szc < seg->s_szc);
4829 szc = (ierr == -1) ? szc - 1 : szc + 1;
4830 } else {
4831 /*
4832 * For non COW faults and segvn_anypgsz == 0
4833 * we need to be careful not to loop forever
4834 * if existing page is found with szc other
4835 * than 0 or seg->s_szc. This could be due
4836 * to page relocations on behalf of DR or
4837 * more likely large page creation. For this
4838 * case simply re-size to existing page's szc
4839 * if returned by anon_map_getpages().
4840 */
4841 if (ppa_szc == (uint_t)-1) {
4842 szc = (ierr == -1) ? 0 : seg->s_szc;
4843 } else {
4844 ASSERT(ppa_szc <= seg->s_szc);
4845 ASSERT(ierr == -2 || ppa_szc < szc);
4846 ASSERT(ierr == -1 || ppa_szc > szc);
4847 szc = ppa_szc;
4848 }
4849 }
4850
4851 pgsz = page_get_pagesize(szc);
4852 pages = btop(pgsz);
4853 ASSERT(type != F_SOFTLOCK || ierr == -1 ||
4854 (IS_P2ALIGNED(a, pgsz) && IS_P2ALIGNED(lpgeaddr, pgsz)));
4855 if (type == F_SOFTLOCK) {
4856 /*
4857 * For softlocks we cannot reduce the fault area
4858 * (calculated based on the largest page size for this
4859 * segment) for size down and a is already next
4860 * page size aligned as assertted above for size
4861 * ups. Therefore just continue in case of softlock.
4862 */
4863 VM_STAT_ADD(segvnvmstats.fltanpages[9]);
4864 continue; /* keep lint happy */
4865 } else if (ierr == -2) {
4866
4867 /*
4868 * Size up case. Note lpgaddr may only be needed for
4869 * softlock case so we don't adjust it here.
4870 */
4871 VM_STAT_ADD(segvnvmstats.fltanpages[10]);
4872 a = (caddr_t)P2ALIGN((uintptr_t)a, pgsz);
4873 ASSERT(a >= lpgaddr);
4874 lpgeaddr = (caddr_t)P2ROUNDUP((uintptr_t)eaddr, pgsz);
4875 aindx = svd->anon_index + seg_page(seg, a);
4876 vpage = (svd->vpage != NULL) ?
4877 &svd->vpage[seg_page(seg, a)] : NULL;
4878 } else {
4879 /*
4880 * Size down case. Note lpgaddr may only be needed for
4881 * softlock case so we don't adjust it here.
4882 */
4883 VM_STAT_ADD(segvnvmstats.fltanpages[11]);
4884 ASSERT(IS_P2ALIGNED(a, pgsz));
4885 ASSERT(IS_P2ALIGNED(lpgeaddr, pgsz));
4886 lpgeaddr = (caddr_t)P2ROUNDUP((uintptr_t)eaddr, pgsz);
4887 ASSERT(a < lpgeaddr);
4888 if (a < addr) {
4889 /*
4890 * The beginning of the large page region can
4891 * be pulled to the right to make a smaller
4892 * region. We haven't yet faulted a single
4893 * page.
4894 */
4895 VM_STAT_ADD(segvnvmstats.fltanpages[12]);
4896 a = (caddr_t)P2ALIGN((uintptr_t)addr, pgsz);
4897 ASSERT(a >= lpgaddr);
4898 aindx = svd->anon_index + seg_page(seg, a);
4899 vpage = (svd->vpage != NULL) ?
4900 &svd->vpage[seg_page(seg, a)] : NULL;
4901 }
4902 }
4903 }
4904 VM_STAT_ADD(segvnvmstats.fltanpages[13]);
4905 ANON_LOCK_EXIT(&->a_rwlock);
4906 kmem_cache_free(segvn_szc_cache[ppaszc], ppa);
4907 return (0);
4908 error:
4909 VM_STAT_ADD(segvnvmstats.fltanpages[14]);
4910 ANON_LOCK_EXIT(&->a_rwlock);
4911 kmem_cache_free(segvn_szc_cache[ppaszc], ppa);
4912 if (type == F_SOFTLOCK && a > lpgaddr) {
4913 VM_STAT_ADD(segvnvmstats.fltanpages[15]);
4914 segvn_softunlock(seg, lpgaddr, a - lpgaddr, S_OTHER);
4915 }
4916 return (err);
4917 }
4918
4919 int fltadvice = 1; /* set to free behind pages for sequential access */
4920
4921 /*
4922 * This routine is called via a machine specific fault handling routine.
4923 * It is also called by software routines wishing to lock or unlock
4924 * a range of addresses.
4925 *
4926 * Here is the basic algorithm:
4927 * If unlocking
4928 * Call segvn_softunlock
4929 * Return
4930 * endif
4931 * Checking and set up work
4932 * If we will need some non-anonymous pages
4933 * Call VOP_GETPAGE over the range of non-anonymous pages
4934 * endif
4935 * Loop over all addresses requested
4936 * Call segvn_faultpage passing in page list
4937 * to load up translations and handle anonymous pages
4938 * endloop
4939 * Load up translation to any additional pages in page list not
4940 * already handled that fit into this segment
4941 */
4942 static faultcode_t
segvn_fault(struct hat * hat,struct seg * seg,caddr_t addr,size_t len,enum fault_type type,enum seg_rw rw)4943 segvn_fault(struct hat *hat, struct seg *seg, caddr_t addr, size_t len,
4944 enum fault_type type, enum seg_rw rw)
4945 {
4946 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
4947 page_t **plp, **ppp, *pp;
4948 u_offset_t off;
4949 caddr_t a;
4950 struct vpage *vpage;
4951 uint_t vpprot, prot;
4952 int err;
4953 page_t *pl[PVN_GETPAGE_NUM + 1];
4954 size_t plsz, pl_alloc_sz;
4955 size_t page;
4956 ulong_t anon_index;
4957 struct anon_map *amp;
4958 int dogetpage = 0;
4959 caddr_t lpgaddr, lpgeaddr;
4960 size_t pgsz;
4961 anon_sync_obj_t cookie;
4962 int brkcow = BREAK_COW_SHARE(rw, type, svd->type);
4963
4964 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
4965 ASSERT(svd->amp == NULL || svd->rcookie == HAT_INVALID_REGION_COOKIE);
4966
4967 /*
4968 * First handle the easy stuff
4969 */
4970 if (type == F_SOFTUNLOCK) {
4971 if (rw == S_READ_NOCOW) {
4972 rw = S_READ;
4973 ASSERT(AS_WRITE_HELD(seg->s_as));
4974 }
4975 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
4976 pgsz = (seg->s_szc == 0) ? PAGESIZE :
4977 page_get_pagesize(seg->s_szc);
4978 VM_STAT_COND_ADD(pgsz > PAGESIZE, segvnvmstats.fltanpages[16]);
4979 CALC_LPG_REGION(pgsz, seg, addr, len, lpgaddr, lpgeaddr);
4980 segvn_softunlock(seg, lpgaddr, lpgeaddr - lpgaddr, rw);
4981 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
4982 return (0);
4983 }
4984
4985 ASSERT(svd->tr_state == SEGVN_TR_OFF ||
4986 !HAT_IS_REGION_COOKIE_VALID(svd->rcookie));
4987 if (brkcow == 0) {
4988 if (svd->tr_state == SEGVN_TR_INIT) {
4989 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
4990 if (svd->tr_state == SEGVN_TR_INIT) {
4991 ASSERT(svd->vp != NULL && svd->amp == NULL);
4992 ASSERT(svd->flags & MAP_TEXT);
4993 ASSERT(svd->type == MAP_PRIVATE);
4994 segvn_textrepl(seg);
4995 ASSERT(svd->tr_state != SEGVN_TR_INIT);
4996 ASSERT(svd->tr_state != SEGVN_TR_ON ||
4997 svd->amp != NULL);
4998 }
4999 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5000 }
5001 } else if (svd->tr_state != SEGVN_TR_OFF) {
5002 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
5003
5004 if (rw == S_WRITE && svd->tr_state != SEGVN_TR_OFF) {
5005 ASSERT(!svd->pageprot && !(svd->prot & PROT_WRITE));
5006 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5007 return (FC_PROT);
5008 }
5009
5010 if (svd->tr_state == SEGVN_TR_ON) {
5011 ASSERT(svd->vp != NULL && svd->amp != NULL);
5012 segvn_textunrepl(seg, 0);
5013 ASSERT(svd->amp == NULL &&
5014 svd->tr_state == SEGVN_TR_OFF);
5015 } else if (svd->tr_state != SEGVN_TR_OFF) {
5016 svd->tr_state = SEGVN_TR_OFF;
5017 }
5018 ASSERT(svd->amp == NULL && svd->tr_state == SEGVN_TR_OFF);
5019 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5020 }
5021
5022 top:
5023 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
5024
5025 /*
5026 * If we have the same protections for the entire segment,
5027 * insure that the access being attempted is legitimate.
5028 */
5029
5030 if (svd->pageprot == 0) {
5031 uint_t protchk;
5032
5033 switch (rw) {
5034 case S_READ:
5035 case S_READ_NOCOW:
5036 protchk = PROT_READ;
5037 break;
5038 case S_WRITE:
5039 protchk = PROT_WRITE;
5040 break;
5041 case S_EXEC:
5042 protchk = PROT_EXEC;
5043 break;
5044 case S_OTHER:
5045 default:
5046 protchk = PROT_READ | PROT_WRITE | PROT_EXEC;
5047 break;
5048 }
5049
5050 if ((svd->prot & protchk) == 0) {
5051 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5052 return (FC_PROT); /* illegal access type */
5053 }
5054 }
5055
5056 if (brkcow && HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
5057 /* this must be SOFTLOCK S_READ fault */
5058 ASSERT(svd->amp == NULL);
5059 ASSERT(svd->tr_state == SEGVN_TR_OFF);
5060 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5061 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
5062 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
5063 /*
5064 * this must be the first ever non S_READ_NOCOW
5065 * softlock for this segment.
5066 */
5067 ASSERT(svd->softlockcnt == 0);
5068 hat_leave_region(seg->s_as->a_hat, svd->rcookie,
5069 HAT_REGION_TEXT);
5070 svd->rcookie = HAT_INVALID_REGION_COOKIE;
5071 }
5072 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5073 goto top;
5074 }
5075
5076 /*
5077 * We can't allow the long term use of softlocks for vmpss segments,
5078 * because in some file truncation cases we should be able to demote
5079 * the segment, which requires that there are no softlocks. The
5080 * only case where it's ok to allow a SOFTLOCK fault against a vmpss
5081 * segment is S_READ_NOCOW, where the caller holds the address space
5082 * locked as writer and calls softunlock before dropping the as lock.
5083 * S_READ_NOCOW is used by /proc to read memory from another user.
5084 *
5085 * Another deadlock between SOFTLOCK and file truncation can happen
5086 * because segvn_fault_vnodepages() calls the FS one pagesize at
5087 * a time. A second VOP_GETPAGE() call by segvn_fault_vnodepages()
5088 * can cause a deadlock because the first set of page_t's remain
5089 * locked SE_SHARED. To avoid this, we demote segments on a first
5090 * SOFTLOCK if they have a length greater than the segment's
5091 * page size.
5092 *
5093 * So for now, we only avoid demoting a segment on a SOFTLOCK when
5094 * the access type is S_READ_NOCOW and the fault length is less than
5095 * or equal to the segment's page size. While this is quite restrictive,
5096 * it should be the most common case of SOFTLOCK against a vmpss
5097 * segment.
5098 *
5099 * For S_READ_NOCOW, it's safe not to do a copy on write because the
5100 * caller makes sure no COW will be caused by another thread for a
5101 * softlocked page.
5102 */
5103 if (type == F_SOFTLOCK && svd->vp != NULL && seg->s_szc != 0) {
5104 int demote = 0;
5105
5106 if (rw != S_READ_NOCOW) {
5107 demote = 1;
5108 }
5109 if (!demote && len > PAGESIZE) {
5110 pgsz = page_get_pagesize(seg->s_szc);
5111 CALC_LPG_REGION(pgsz, seg, addr, len, lpgaddr,
5112 lpgeaddr);
5113 if (lpgeaddr - lpgaddr > pgsz) {
5114 demote = 1;
5115 }
5116 }
5117
5118 ASSERT(demote || AS_WRITE_HELD(seg->s_as));
5119
5120 if (demote) {
5121 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5122 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
5123 if (seg->s_szc != 0) {
5124 segvn_vmpss_clrszc_cnt++;
5125 ASSERT(svd->softlockcnt == 0);
5126 err = segvn_clrszc(seg);
5127 if (err) {
5128 segvn_vmpss_clrszc_err++;
5129 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5130 return (FC_MAKE_ERR(err));
5131 }
5132 }
5133 ASSERT(seg->s_szc == 0);
5134 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5135 goto top;
5136 }
5137 }
5138
5139 /*
5140 * Check to see if we need to allocate an anon_map structure.
5141 */
5142 if (svd->amp == NULL && (svd->vp == NULL || brkcow)) {
5143 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
5144 /*
5145 * Drop the "read" lock on the segment and acquire
5146 * the "write" version since we have to allocate the
5147 * anon_map.
5148 */
5149 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5150 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
5151
5152 if (svd->amp == NULL) {
5153 svd->amp = anonmap_alloc(seg->s_size, 0, ANON_SLEEP);
5154 svd->amp->a_szc = seg->s_szc;
5155 }
5156 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5157
5158 /*
5159 * Start all over again since segment protections
5160 * may have changed after we dropped the "read" lock.
5161 */
5162 goto top;
5163 }
5164
5165 /*
5166 * S_READ_NOCOW vs S_READ distinction was
5167 * only needed for the code above. After
5168 * that we treat it as S_READ.
5169 */
5170 if (rw == S_READ_NOCOW) {
5171 ASSERT(type == F_SOFTLOCK);
5172 ASSERT(AS_WRITE_HELD(seg->s_as));
5173 rw = S_READ;
5174 }
5175
5176 amp = svd->amp;
5177
5178 /*
5179 * MADV_SEQUENTIAL work is ignored for large page segments.
5180 */
5181 if (seg->s_szc != 0) {
5182 pgsz = page_get_pagesize(seg->s_szc);
5183 ASSERT(SEGVN_LOCK_HELD(seg->s_as, &svd->lock));
5184 CALC_LPG_REGION(pgsz, seg, addr, len, lpgaddr, lpgeaddr);
5185 if (svd->vp == NULL) {
5186 err = segvn_fault_anonpages(hat, seg, lpgaddr,
5187 lpgeaddr, type, rw, addr, addr + len, brkcow);
5188 } else {
5189 err = segvn_fault_vnodepages(hat, seg, lpgaddr,
5190 lpgeaddr, type, rw, addr, addr + len, brkcow);
5191 if (err == IE_RETRY) {
5192 ASSERT(seg->s_szc == 0);
5193 ASSERT(SEGVN_READ_HELD(seg->s_as, &svd->lock));
5194 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5195 goto top;
5196 }
5197 }
5198 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5199 return (err);
5200 }
5201
5202 page = seg_page(seg, addr);
5203 if (amp != NULL) {
5204 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
5205 anon_index = svd->anon_index + page;
5206
5207 if (type == F_PROT && rw == S_READ &&
5208 svd->tr_state == SEGVN_TR_OFF &&
5209 svd->type == MAP_PRIVATE && svd->pageprot == 0) {
5210 size_t index = anon_index;
5211 struct anon *ap;
5212
5213 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
5214 /*
5215 * The fast path could apply to S_WRITE also, except
5216 * that the protection fault could be caused by lazy
5217 * tlb flush when ro->rw. In this case, the pte is
5218 * RW already. But RO in the other cpu's tlb causes
5219 * the fault. Since hat_chgprot won't do anything if
5220 * pte doesn't change, we may end up faulting
5221 * indefinitely until the RO tlb entry gets replaced.
5222 */
5223 for (a = addr; a < addr + len; a += PAGESIZE, index++) {
5224 anon_array_enter(amp, index, &cookie);
5225 ap = anon_get_ptr(amp->ahp, index);
5226 anon_array_exit(&cookie);
5227 if ((ap == NULL) || (ap->an_refcnt != 1)) {
5228 ANON_LOCK_EXIT(&->a_rwlock);
5229 goto slow;
5230 }
5231 }
5232 hat_chgprot(seg->s_as->a_hat, addr, len, svd->prot);
5233 ANON_LOCK_EXIT(&->a_rwlock);
5234 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5235 return (0);
5236 }
5237 }
5238 slow:
5239
5240 if (svd->vpage == NULL)
5241 vpage = NULL;
5242 else
5243 vpage = &svd->vpage[page];
5244
5245 off = svd->offset + (uintptr_t)(addr - seg->s_base);
5246
5247 /*
5248 * If MADV_SEQUENTIAL has been set for the particular page we
5249 * are faulting on, free behind all pages in the segment and put
5250 * them on the free list.
5251 */
5252
5253 if ((page != 0) && fltadvice && svd->tr_state != SEGVN_TR_ON) {
5254 struct vpage *vpp;
5255 ulong_t fanon_index;
5256 size_t fpage;
5257 u_offset_t pgoff, fpgoff;
5258 struct vnode *fvp;
5259 struct anon *fap = NULL;
5260
5261 if (svd->advice == MADV_SEQUENTIAL ||
5262 (svd->pageadvice &&
5263 VPP_ADVICE(vpage) == MADV_SEQUENTIAL)) {
5264 pgoff = off - PAGESIZE;
5265 fpage = page - 1;
5266 if (vpage != NULL)
5267 vpp = &svd->vpage[fpage];
5268 if (amp != NULL)
5269 fanon_index = svd->anon_index + fpage;
5270
5271 while (pgoff > svd->offset) {
5272 if (svd->advice != MADV_SEQUENTIAL &&
5273 (!svd->pageadvice || (vpage &&
5274 VPP_ADVICE(vpp) != MADV_SEQUENTIAL)))
5275 break;
5276
5277 /*
5278 * If this is an anon page, we must find the
5279 * correct <vp, offset> for it
5280 */
5281 fap = NULL;
5282 if (amp != NULL) {
5283 ANON_LOCK_ENTER(&->a_rwlock,
5284 RW_READER);
5285 anon_array_enter(amp, fanon_index,
5286 &cookie);
5287 fap = anon_get_ptr(amp->ahp,
5288 fanon_index);
5289 if (fap != NULL) {
5290 swap_xlate(fap, &fvp, &fpgoff);
5291 } else {
5292 fpgoff = pgoff;
5293 fvp = svd->vp;
5294 }
5295 anon_array_exit(&cookie);
5296 ANON_LOCK_EXIT(&->a_rwlock);
5297 } else {
5298 fpgoff = pgoff;
5299 fvp = svd->vp;
5300 }
5301 if (fvp == NULL)
5302 break; /* XXX */
5303 /*
5304 * Skip pages that are free or have an
5305 * "exclusive" lock.
5306 */
5307 pp = page_lookup_nowait(fvp, fpgoff, SE_SHARED);
5308 if (pp == NULL)
5309 break;
5310 /*
5311 * We don't need the page_struct_lock to test
5312 * as this is only advisory; even if we
5313 * acquire it someone might race in and lock
5314 * the page after we unlock and before the
5315 * PUTPAGE, then VOP_PUTPAGE will do nothing.
5316 */
5317 if (pp->p_lckcnt == 0 && pp->p_cowcnt == 0) {
5318 /*
5319 * Hold the vnode before releasing
5320 * the page lock to prevent it from
5321 * being freed and re-used by some
5322 * other thread.
5323 */
5324 VN_HOLD(fvp);
5325 page_unlock(pp);
5326 /*
5327 * We should build a page list
5328 * to kluster putpages XXX
5329 */
5330 (void) VOP_PUTPAGE(fvp,
5331 (offset_t)fpgoff, PAGESIZE,
5332 (B_DONTNEED|B_FREE|B_ASYNC),
5333 svd->cred, NULL);
5334 VN_RELE(fvp);
5335 } else {
5336 /*
5337 * XXX - Should the loop terminate if
5338 * the page is `locked'?
5339 */
5340 page_unlock(pp);
5341 }
5342 --vpp;
5343 --fanon_index;
5344 pgoff -= PAGESIZE;
5345 }
5346 }
5347 }
5348
5349 plp = pl;
5350 *plp = NULL;
5351 pl_alloc_sz = 0;
5352
5353 /*
5354 * See if we need to call VOP_GETPAGE for
5355 * *any* of the range being faulted on.
5356 * We can skip all of this work if there
5357 * was no original vnode.
5358 */
5359 if (svd->vp != NULL) {
5360 u_offset_t vp_off;
5361 size_t vp_len;
5362 struct anon *ap;
5363 vnode_t *vp;
5364
5365 vp_off = off;
5366 vp_len = len;
5367
5368 if (amp == NULL)
5369 dogetpage = 1;
5370 else {
5371 /*
5372 * Only acquire reader lock to prevent amp->ahp
5373 * from being changed. It's ok to miss pages,
5374 * hence we don't do anon_array_enter
5375 */
5376 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
5377 ap = anon_get_ptr(amp->ahp, anon_index);
5378
5379 if (len <= PAGESIZE)
5380 /* inline non_anon() */
5381 dogetpage = (ap == NULL);
5382 else
5383 dogetpage = non_anon(amp->ahp, anon_index,
5384 &vp_off, &vp_len);
5385 ANON_LOCK_EXIT(&->a_rwlock);
5386 }
5387
5388 if (dogetpage) {
5389 enum seg_rw arw;
5390 struct as *as = seg->s_as;
5391
5392 if (len > ptob((sizeof (pl) / sizeof (pl[0])) - 1)) {
5393 /*
5394 * Page list won't fit in local array,
5395 * allocate one of the needed size.
5396 */
5397 pl_alloc_sz =
5398 (btop(len) + 1) * sizeof (page_t *);
5399 plp = kmem_alloc(pl_alloc_sz, KM_SLEEP);
5400 plp[0] = NULL;
5401 plsz = len;
5402 } else if (rw == S_WRITE && svd->type == MAP_PRIVATE ||
5403 svd->tr_state == SEGVN_TR_ON || rw == S_OTHER ||
5404 (((size_t)(addr + PAGESIZE) <
5405 (size_t)(seg->s_base + seg->s_size)) &&
5406 hat_probe(as->a_hat, addr + PAGESIZE))) {
5407 /*
5408 * Ask VOP_GETPAGE to return the exact number
5409 * of pages if
5410 * (a) this is a COW fault, or
5411 * (b) this is a software fault, or
5412 * (c) next page is already mapped.
5413 */
5414 plsz = len;
5415 } else {
5416 /*
5417 * Ask VOP_GETPAGE to return adjacent pages
5418 * within the segment.
5419 */
5420 plsz = MIN((size_t)PVN_GETPAGE_SZ, (size_t)
5421 ((seg->s_base + seg->s_size) - addr));
5422 ASSERT((addr + plsz) <=
5423 (seg->s_base + seg->s_size));
5424 }
5425
5426 /*
5427 * Need to get some non-anonymous pages.
5428 * We need to make only one call to GETPAGE to do
5429 * this to prevent certain deadlocking conditions
5430 * when we are doing locking. In this case
5431 * non_anon() should have picked up the smallest
5432 * range which includes all the non-anonymous
5433 * pages in the requested range. We have to
5434 * be careful regarding which rw flag to pass in
5435 * because on a private mapping, the underlying
5436 * object is never allowed to be written.
5437 */
5438 if (rw == S_WRITE && svd->type == MAP_PRIVATE) {
5439 arw = S_READ;
5440 } else {
5441 arw = rw;
5442 }
5443 vp = svd->vp;
5444 TRACE_3(TR_FAC_VM, TR_SEGVN_GETPAGE,
5445 "segvn_getpage:seg %p addr %p vp %p",
5446 seg, addr, vp);
5447 err = VOP_GETPAGE(vp, (offset_t)vp_off, vp_len,
5448 &vpprot, plp, plsz, seg, addr + (vp_off - off), arw,
5449 svd->cred, NULL);
5450 if (err) {
5451 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5452 segvn_pagelist_rele(plp);
5453 if (pl_alloc_sz)
5454 kmem_free(plp, pl_alloc_sz);
5455 return (FC_MAKE_ERR(err));
5456 }
5457 if (svd->type == MAP_PRIVATE)
5458 vpprot &= ~PROT_WRITE;
5459 }
5460 }
5461
5462 /*
5463 * N.B. at this time the plp array has all the needed non-anon
5464 * pages in addition to (possibly) having some adjacent pages.
5465 */
5466
5467 /*
5468 * Always acquire the anon_array_lock to prevent
5469 * 2 threads from allocating separate anon slots for
5470 * the same "addr".
5471 *
5472 * If this is a copy-on-write fault and we don't already
5473 * have the anon_array_lock, acquire it to prevent the
5474 * fault routine from handling multiple copy-on-write faults
5475 * on the same "addr" in the same address space.
5476 *
5477 * Only one thread should deal with the fault since after
5478 * it is handled, the other threads can acquire a translation
5479 * to the newly created private page. This prevents two or
5480 * more threads from creating different private pages for the
5481 * same fault.
5482 *
5483 * We grab "serialization" lock here if this is a MAP_PRIVATE segment
5484 * to prevent deadlock between this thread and another thread
5485 * which has soft-locked this page and wants to acquire serial_lock.
5486 * ( bug 4026339 )
5487 *
5488 * The fix for bug 4026339 becomes unnecessary when using the
5489 * locking scheme with per amp rwlock and a global set of hash
5490 * lock, anon_array_lock. If we steal a vnode page when low
5491 * on memory and upgrad the page lock through page_rename,
5492 * then the page is PAGE_HANDLED, nothing needs to be done
5493 * for this page after returning from segvn_faultpage.
5494 *
5495 * But really, the page lock should be downgraded after
5496 * the stolen page is page_rename'd.
5497 */
5498
5499 if (amp != NULL)
5500 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
5501
5502 /*
5503 * Ok, now loop over the address range and handle faults
5504 */
5505 for (a = addr; a < addr + len; a += PAGESIZE, off += PAGESIZE) {
5506 err = segvn_faultpage(hat, seg, a, off, vpage, plp, vpprot,
5507 type, rw, brkcow);
5508 if (err) {
5509 if (amp != NULL)
5510 ANON_LOCK_EXIT(&->a_rwlock);
5511 if (type == F_SOFTLOCK && a > addr) {
5512 segvn_softunlock(seg, addr, (a - addr),
5513 S_OTHER);
5514 }
5515 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5516 segvn_pagelist_rele(plp);
5517 if (pl_alloc_sz)
5518 kmem_free(plp, pl_alloc_sz);
5519 return (err);
5520 }
5521 if (vpage) {
5522 vpage++;
5523 } else if (svd->vpage) {
5524 page = seg_page(seg, addr);
5525 vpage = &svd->vpage[++page];
5526 }
5527 }
5528
5529 /* Didn't get pages from the underlying fs so we're done */
5530 if (!dogetpage)
5531 goto done;
5532
5533 /*
5534 * Now handle any other pages in the list returned.
5535 * If the page can be used, load up the translations now.
5536 * Note that the for loop will only be entered if "plp"
5537 * is pointing to a non-NULL page pointer which means that
5538 * VOP_GETPAGE() was called and vpprot has been initialized.
5539 */
5540 if (svd->pageprot == 0)
5541 prot = svd->prot & vpprot;
5542
5543
5544 /*
5545 * Large Files: diff should be unsigned value because we started
5546 * supporting > 2GB segment sizes from 2.5.1 and when a
5547 * large file of size > 2GB gets mapped to address space
5548 * the diff value can be > 2GB.
5549 */
5550
5551 for (ppp = plp; (pp = *ppp) != NULL; ppp++) {
5552 size_t diff;
5553 struct anon *ap;
5554 int anon_index;
5555 anon_sync_obj_t cookie;
5556 int hat_flag = HAT_LOAD_ADV;
5557
5558 if (svd->flags & MAP_TEXT) {
5559 hat_flag |= HAT_LOAD_TEXT;
5560 }
5561
5562 if (pp == PAGE_HANDLED)
5563 continue;
5564
5565 if (svd->tr_state != SEGVN_TR_ON &&
5566 pp->p_offset >= svd->offset &&
5567 pp->p_offset < svd->offset + seg->s_size) {
5568
5569 diff = pp->p_offset - svd->offset;
5570
5571 /*
5572 * Large Files: Following is the assertion
5573 * validating the above cast.
5574 */
5575 ASSERT(svd->vp == pp->p_vnode);
5576
5577 page = btop(diff);
5578 if (svd->pageprot)
5579 prot = VPP_PROT(&svd->vpage[page]) & vpprot;
5580
5581 /*
5582 * Prevent other threads in the address space from
5583 * creating private pages (i.e., allocating anon slots)
5584 * while we are in the process of loading translations
5585 * to additional pages returned by the underlying
5586 * object.
5587 */
5588 if (amp != NULL) {
5589 anon_index = svd->anon_index + page;
5590 anon_array_enter(amp, anon_index, &cookie);
5591 ap = anon_get_ptr(amp->ahp, anon_index);
5592 }
5593 if ((amp == NULL) || (ap == NULL)) {
5594 if (IS_VMODSORT(pp->p_vnode) ||
5595 enable_mbit_wa) {
5596 if (rw == S_WRITE)
5597 hat_setmod(pp);
5598 else if (rw != S_OTHER &&
5599 !hat_ismod(pp))
5600 prot &= ~PROT_WRITE;
5601 }
5602 /*
5603 * Skip mapping read ahead pages marked
5604 * for migration, so they will get migrated
5605 * properly on fault
5606 */
5607 ASSERT(amp == NULL ||
5608 svd->rcookie == HAT_INVALID_REGION_COOKIE);
5609 if ((prot & PROT_READ) && !PP_ISMIGRATE(pp)) {
5610 hat_memload_region(hat,
5611 seg->s_base + diff,
5612 pp, prot, hat_flag,
5613 svd->rcookie);
5614 }
5615 }
5616 if (amp != NULL)
5617 anon_array_exit(&cookie);
5618 }
5619 page_unlock(pp);
5620 }
5621 done:
5622 if (amp != NULL)
5623 ANON_LOCK_EXIT(&->a_rwlock);
5624 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5625 if (pl_alloc_sz)
5626 kmem_free(plp, pl_alloc_sz);
5627 return (0);
5628 }
5629
5630 /*
5631 * This routine is used to start I/O on pages asynchronously. XXX it will
5632 * only create PAGESIZE pages. At fault time they will be relocated into
5633 * larger pages.
5634 */
5635 static faultcode_t
segvn_faulta(struct seg * seg,caddr_t addr)5636 segvn_faulta(struct seg *seg, caddr_t addr)
5637 {
5638 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
5639 int err;
5640 struct anon_map *amp;
5641 vnode_t *vp;
5642
5643 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
5644
5645 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
5646 if ((amp = svd->amp) != NULL) {
5647 struct anon *ap;
5648
5649 /*
5650 * Reader lock to prevent amp->ahp from being changed.
5651 * This is advisory, it's ok to miss a page, so
5652 * we don't do anon_array_enter lock.
5653 */
5654 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
5655 if ((ap = anon_get_ptr(amp->ahp,
5656 svd->anon_index + seg_page(seg, addr))) != NULL) {
5657
5658 err = anon_getpage(&ap, NULL, NULL,
5659 0, seg, addr, S_READ, svd->cred);
5660
5661 ANON_LOCK_EXIT(&->a_rwlock);
5662 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5663 if (err)
5664 return (FC_MAKE_ERR(err));
5665 return (0);
5666 }
5667 ANON_LOCK_EXIT(&->a_rwlock);
5668 }
5669
5670 if (svd->vp == NULL) {
5671 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5672 return (0); /* zfod page - do nothing now */
5673 }
5674
5675 vp = svd->vp;
5676 TRACE_3(TR_FAC_VM, TR_SEGVN_GETPAGE,
5677 "segvn_getpage:seg %p addr %p vp %p", seg, addr, vp);
5678 err = VOP_GETPAGE(vp,
5679 (offset_t)(svd->offset + (uintptr_t)(addr - seg->s_base)),
5680 PAGESIZE, NULL, NULL, 0, seg, addr,
5681 S_OTHER, svd->cred, NULL);
5682
5683 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5684 if (err)
5685 return (FC_MAKE_ERR(err));
5686 return (0);
5687 }
5688
5689 static int
segvn_setprot(struct seg * seg,caddr_t addr,size_t len,uint_t prot)5690 segvn_setprot(struct seg *seg, caddr_t addr, size_t len, uint_t prot)
5691 {
5692 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
5693 struct vpage *cvp, *svp, *evp;
5694 struct vnode *vp;
5695 size_t pgsz;
5696 pgcnt_t pgcnt;
5697 anon_sync_obj_t cookie;
5698 int unload_done = 0;
5699
5700 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
5701
5702 if ((svd->maxprot & prot) != prot)
5703 return (EACCES); /* violated maxprot */
5704
5705 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
5706
5707 /* return if prot is the same */
5708 if (!svd->pageprot && svd->prot == prot) {
5709 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5710 return (0);
5711 }
5712
5713 /*
5714 * Since we change protections we first have to flush the cache.
5715 * This makes sure all the pagelock calls have to recheck
5716 * protections.
5717 */
5718 if (svd->softlockcnt > 0) {
5719 ASSERT(svd->tr_state == SEGVN_TR_OFF);
5720
5721 /*
5722 * If this is shared segment non 0 softlockcnt
5723 * means locked pages are still in use.
5724 */
5725 if (svd->type == MAP_SHARED) {
5726 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5727 return (EAGAIN);
5728 }
5729
5730 /*
5731 * Since we do have the segvn writers lock nobody can fill
5732 * the cache with entries belonging to this seg during
5733 * the purge. The flush either succeeds or we still have
5734 * pending I/Os.
5735 */
5736 segvn_purge(seg);
5737 if (svd->softlockcnt > 0) {
5738 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5739 return (EAGAIN);
5740 }
5741 }
5742
5743 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
5744 ASSERT(svd->amp == NULL);
5745 ASSERT(svd->tr_state == SEGVN_TR_OFF);
5746 hat_leave_region(seg->s_as->a_hat, svd->rcookie,
5747 HAT_REGION_TEXT);
5748 svd->rcookie = HAT_INVALID_REGION_COOKIE;
5749 unload_done = 1;
5750 } else if (svd->tr_state == SEGVN_TR_INIT) {
5751 svd->tr_state = SEGVN_TR_OFF;
5752 } else if (svd->tr_state == SEGVN_TR_ON) {
5753 ASSERT(svd->amp != NULL);
5754 segvn_textunrepl(seg, 0);
5755 ASSERT(svd->amp == NULL && svd->tr_state == SEGVN_TR_OFF);
5756 unload_done = 1;
5757 }
5758
5759 if ((prot & PROT_WRITE) && svd->type == MAP_SHARED &&
5760 svd->vp != NULL && (svd->vp->v_flag & VVMEXEC)) {
5761 ASSERT(vn_is_mapped(svd->vp, V_WRITE));
5762 segvn_inval_trcache(svd->vp);
5763 }
5764 if (seg->s_szc != 0) {
5765 int err;
5766 pgsz = page_get_pagesize(seg->s_szc);
5767 pgcnt = pgsz >> PAGESHIFT;
5768 ASSERT(IS_P2ALIGNED(pgcnt, pgcnt));
5769 if (!IS_P2ALIGNED(addr, pgsz) || !IS_P2ALIGNED(len, pgsz)) {
5770 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5771 ASSERT(seg->s_base != addr || seg->s_size != len);
5772 /*
5773 * If we are holding the as lock as a reader then
5774 * we need to return IE_RETRY and let the as
5775 * layer drop and re-acquire the lock as a writer.
5776 */
5777 if (AS_READ_HELD(seg->s_as))
5778 return (IE_RETRY);
5779 VM_STAT_ADD(segvnvmstats.demoterange[1]);
5780 if (svd->type == MAP_PRIVATE || svd->vp != NULL) {
5781 err = segvn_demote_range(seg, addr, len,
5782 SDR_END, 0);
5783 } else {
5784 uint_t szcvec = map_pgszcvec(seg->s_base,
5785 pgsz, (uintptr_t)seg->s_base,
5786 (svd->flags & MAP_TEXT), MAPPGSZC_SHM, 0);
5787 err = segvn_demote_range(seg, addr, len,
5788 SDR_END, szcvec);
5789 }
5790 if (err == 0)
5791 return (IE_RETRY);
5792 if (err == ENOMEM)
5793 return (IE_NOMEM);
5794 return (err);
5795 }
5796 }
5797
5798
5799 /*
5800 * If it's a private mapping and we're making it writable then we
5801 * may have to reserve the additional swap space now. If we are
5802 * making writable only a part of the segment then we use its vpage
5803 * array to keep a record of the pages for which we have reserved
5804 * swap. In this case we set the pageswap field in the segment's
5805 * segvn structure to record this.
5806 *
5807 * If it's a private mapping to a file (i.e., vp != NULL) and we're
5808 * removing write permission on the entire segment and we haven't
5809 * modified any pages, we can release the swap space.
5810 */
5811 if (svd->type == MAP_PRIVATE) {
5812 if (prot & PROT_WRITE) {
5813 if (!(svd->flags & MAP_NORESERVE) &&
5814 !(svd->swresv && svd->pageswap == 0)) {
5815 size_t sz = 0;
5816
5817 /*
5818 * Start by determining how much swap
5819 * space is required.
5820 */
5821 if (addr == seg->s_base &&
5822 len == seg->s_size &&
5823 svd->pageswap == 0) {
5824 /* The whole segment */
5825 sz = seg->s_size;
5826 } else {
5827 /*
5828 * Make sure that the vpage array
5829 * exists, and make a note of the
5830 * range of elements corresponding
5831 * to len.
5832 */
5833 segvn_vpage(seg);
5834 if (svd->vpage == NULL) {
5835 SEGVN_LOCK_EXIT(seg->s_as,
5836 &svd->lock);
5837 return (ENOMEM);
5838 }
5839 svp = &svd->vpage[seg_page(seg, addr)];
5840 evp = &svd->vpage[seg_page(seg,
5841 addr + len)];
5842
5843 if (svd->pageswap == 0) {
5844 /*
5845 * This is the first time we've
5846 * asked for a part of this
5847 * segment, so we need to
5848 * reserve everything we've
5849 * been asked for.
5850 */
5851 sz = len;
5852 } else {
5853 /*
5854 * We have to count the number
5855 * of pages required.
5856 */
5857 for (cvp = svp; cvp < evp;
5858 cvp++) {
5859 if (!VPP_ISSWAPRES(cvp))
5860 sz++;
5861 }
5862 sz <<= PAGESHIFT;
5863 }
5864 }
5865
5866 /* Try to reserve the necessary swap. */
5867 if (anon_resv_zone(sz,
5868 seg->s_as->a_proc->p_zone) == 0) {
5869 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5870 return (IE_NOMEM);
5871 }
5872
5873 /*
5874 * Make a note of how much swap space
5875 * we've reserved.
5876 */
5877 if (svd->pageswap == 0 && sz == seg->s_size) {
5878 svd->swresv = sz;
5879 } else {
5880 ASSERT(svd->vpage != NULL);
5881 svd->swresv += sz;
5882 svd->pageswap = 1;
5883 for (cvp = svp; cvp < evp; cvp++) {
5884 if (!VPP_ISSWAPRES(cvp))
5885 VPP_SETSWAPRES(cvp);
5886 }
5887 }
5888 }
5889 } else {
5890 /*
5891 * Swap space is released only if this segment
5892 * does not map anonymous memory, since read faults
5893 * on such segments still need an anon slot to read
5894 * in the data.
5895 */
5896 if (svd->swresv != 0 && svd->vp != NULL &&
5897 svd->amp == NULL && addr == seg->s_base &&
5898 len == seg->s_size && svd->pageprot == 0) {
5899 ASSERT(svd->pageswap == 0);
5900 anon_unresv_zone(svd->swresv,
5901 seg->s_as->a_proc->p_zone);
5902 svd->swresv = 0;
5903 TRACE_3(TR_FAC_VM, TR_ANON_PROC,
5904 "anon proc:%p %lu %u", seg, 0, 0);
5905 }
5906 }
5907 }
5908
5909 if (addr == seg->s_base && len == seg->s_size && svd->vpage == NULL) {
5910 if (svd->prot == prot) {
5911 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5912 return (0); /* all done */
5913 }
5914 svd->prot = (uchar_t)prot;
5915 } else if (svd->type == MAP_PRIVATE) {
5916 struct anon *ap = NULL;
5917 page_t *pp;
5918 u_offset_t offset, off;
5919 struct anon_map *amp;
5920 ulong_t anon_idx = 0;
5921
5922 /*
5923 * A vpage structure exists or else the change does not
5924 * involve the entire segment. Establish a vpage structure
5925 * if none is there. Then, for each page in the range,
5926 * adjust its individual permissions. Note that write-
5927 * enabling a MAP_PRIVATE page can affect the claims for
5928 * locked down memory. Overcommitting memory terminates
5929 * the operation.
5930 */
5931 segvn_vpage(seg);
5932 if (svd->vpage == NULL) {
5933 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
5934 return (ENOMEM);
5935 }
5936 svd->pageprot = 1;
5937 if ((amp = svd->amp) != NULL) {
5938 anon_idx = svd->anon_index + seg_page(seg, addr);
5939 ASSERT(seg->s_szc == 0 ||
5940 IS_P2ALIGNED(anon_idx, pgcnt));
5941 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
5942 }
5943
5944 offset = svd->offset + (uintptr_t)(addr - seg->s_base);
5945 evp = &svd->vpage[seg_page(seg, addr + len)];
5946
5947 /*
5948 * See Statement at the beginning of segvn_lockop regarding
5949 * the way cowcnts and lckcnts are handled.
5950 */
5951 for (svp = &svd->vpage[seg_page(seg, addr)]; svp < evp; svp++) {
5952
5953 if (seg->s_szc != 0) {
5954 if (amp != NULL) {
5955 anon_array_enter(amp, anon_idx,
5956 &cookie);
5957 }
5958 if (IS_P2ALIGNED(anon_idx, pgcnt) &&
5959 !segvn_claim_pages(seg, svp, offset,
5960 anon_idx, prot)) {
5961 if (amp != NULL) {
5962 anon_array_exit(&cookie);
5963 }
5964 break;
5965 }
5966 if (amp != NULL) {
5967 anon_array_exit(&cookie);
5968 }
5969 anon_idx++;
5970 } else {
5971 if (amp != NULL) {
5972 anon_array_enter(amp, anon_idx,
5973 &cookie);
5974 ap = anon_get_ptr(amp->ahp, anon_idx++);
5975 }
5976
5977 if (VPP_ISPPLOCK(svp) &&
5978 VPP_PROT(svp) != prot) {
5979
5980 if (amp == NULL || ap == NULL) {
5981 vp = svd->vp;
5982 off = offset;
5983 } else
5984 swap_xlate(ap, &vp, &off);
5985 if (amp != NULL)
5986 anon_array_exit(&cookie);
5987
5988 if ((pp = page_lookup(vp, off,
5989 SE_SHARED)) == NULL) {
5990 panic("segvn_setprot: no page");
5991 /*NOTREACHED*/
5992 }
5993 ASSERT(seg->s_szc == 0);
5994 if ((VPP_PROT(svp) ^ prot) &
5995 PROT_WRITE) {
5996 if (prot & PROT_WRITE) {
5997 if (!page_addclaim(
5998 pp)) {
5999 page_unlock(pp);
6000 break;
6001 }
6002 } else {
6003 if (!page_subclaim(
6004 pp)) {
6005 page_unlock(pp);
6006 break;
6007 }
6008 }
6009 }
6010 page_unlock(pp);
6011 } else if (amp != NULL)
6012 anon_array_exit(&cookie);
6013 }
6014 VPP_SETPROT(svp, prot);
6015 offset += PAGESIZE;
6016 }
6017 if (amp != NULL)
6018 ANON_LOCK_EXIT(&->a_rwlock);
6019
6020 /*
6021 * Did we terminate prematurely? If so, simply unload
6022 * the translations to the things we've updated so far.
6023 */
6024 if (svp != evp) {
6025 if (unload_done) {
6026 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6027 return (IE_NOMEM);
6028 }
6029 len = (svp - &svd->vpage[seg_page(seg, addr)]) *
6030 PAGESIZE;
6031 ASSERT(seg->s_szc == 0 || IS_P2ALIGNED(len, pgsz));
6032 if (len != 0)
6033 hat_unload(seg->s_as->a_hat, addr,
6034 len, HAT_UNLOAD);
6035 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6036 return (IE_NOMEM);
6037 }
6038 } else {
6039 segvn_vpage(seg);
6040 if (svd->vpage == NULL) {
6041 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6042 return (ENOMEM);
6043 }
6044 svd->pageprot = 1;
6045 evp = &svd->vpage[seg_page(seg, addr + len)];
6046 for (svp = &svd->vpage[seg_page(seg, addr)]; svp < evp; svp++) {
6047 VPP_SETPROT(svp, prot);
6048 }
6049 }
6050
6051 if (unload_done) {
6052 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6053 return (0);
6054 }
6055
6056 if (((prot & PROT_WRITE) != 0 &&
6057 (svd->vp != NULL || svd->type == MAP_PRIVATE)) ||
6058 (prot & ~PROT_USER) == PROT_NONE) {
6059 /*
6060 * Either private or shared data with write access (in
6061 * which case we need to throw out all former translations
6062 * so that we get the right translations set up on fault
6063 * and we don't allow write access to any copy-on-write pages
6064 * that might be around or to prevent write access to pages
6065 * representing holes in a file), or we don't have permission
6066 * to access the memory at all (in which case we have to
6067 * unload any current translations that might exist).
6068 */
6069 hat_unload(seg->s_as->a_hat, addr, len, HAT_UNLOAD);
6070 } else {
6071 /*
6072 * A shared mapping or a private mapping in which write
6073 * protection is going to be denied - just change all the
6074 * protections over the range of addresses in question.
6075 * segvn does not support any other attributes other
6076 * than prot so we can use hat_chgattr.
6077 */
6078 hat_chgattr(seg->s_as->a_hat, addr, len, prot);
6079 }
6080
6081 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6082
6083 return (0);
6084 }
6085
6086 /*
6087 * segvn_setpagesize is called via SEGOP_SETPAGESIZE from as_setpagesize,
6088 * to determine if the seg is capable of mapping the requested szc.
6089 */
6090 static int
segvn_setpagesize(struct seg * seg,caddr_t addr,size_t len,uint_t szc)6091 segvn_setpagesize(struct seg *seg, caddr_t addr, size_t len, uint_t szc)
6092 {
6093 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6094 struct segvn_data *nsvd;
6095 struct anon_map *amp = svd->amp;
6096 struct seg *nseg;
6097 caddr_t eaddr = addr + len, a;
6098 size_t pgsz = page_get_pagesize(szc);
6099 pgcnt_t pgcnt = page_get_pagecnt(szc);
6100 int err;
6101 u_offset_t off = svd->offset + (uintptr_t)(addr - seg->s_base);
6102
6103 ASSERT(seg->s_as && AS_WRITE_HELD(seg->s_as));
6104 ASSERT(addr >= seg->s_base && eaddr <= seg->s_base + seg->s_size);
6105
6106 if (seg->s_szc == szc || segvn_lpg_disable != 0) {
6107 return (0);
6108 }
6109
6110 /*
6111 * addr should always be pgsz aligned but eaddr may be misaligned if
6112 * it's at the end of the segment.
6113 *
6114 * XXX we should assert this condition since as_setpagesize() logic
6115 * guarantees it.
6116 */
6117 if (!IS_P2ALIGNED(addr, pgsz) ||
6118 (!IS_P2ALIGNED(eaddr, pgsz) &&
6119 eaddr != seg->s_base + seg->s_size)) {
6120
6121 segvn_setpgsz_align_err++;
6122 return (EINVAL);
6123 }
6124
6125 if (amp != NULL && svd->type == MAP_SHARED) {
6126 ulong_t an_idx = svd->anon_index + seg_page(seg, addr);
6127 if (!IS_P2ALIGNED(an_idx, pgcnt)) {
6128
6129 segvn_setpgsz_anon_align_err++;
6130 return (EINVAL);
6131 }
6132 }
6133
6134 if ((svd->flags & MAP_NORESERVE) || seg->s_as == &kas ||
6135 szc > segvn_maxpgszc) {
6136 return (EINVAL);
6137 }
6138
6139 /* paranoid check */
6140 if (svd->vp != NULL &&
6141 (IS_SWAPFSVP(svd->vp) || VN_ISKAS(svd->vp))) {
6142 return (EINVAL);
6143 }
6144
6145 if (seg->s_szc == 0 && svd->vp != NULL &&
6146 map_addr_vacalign_check(addr, off)) {
6147 return (EINVAL);
6148 }
6149
6150 /*
6151 * Check that protections are the same within new page
6152 * size boundaries.
6153 */
6154 if (svd->pageprot) {
6155 for (a = addr; a < eaddr; a += pgsz) {
6156 if ((a + pgsz) > eaddr) {
6157 if (!sameprot(seg, a, eaddr - a)) {
6158 return (EINVAL);
6159 }
6160 } else {
6161 if (!sameprot(seg, a, pgsz)) {
6162 return (EINVAL);
6163 }
6164 }
6165 }
6166 }
6167
6168 /*
6169 * Since we are changing page size we first have to flush
6170 * the cache. This makes sure all the pagelock calls have
6171 * to recheck protections.
6172 */
6173 if (svd->softlockcnt > 0) {
6174 ASSERT(svd->tr_state == SEGVN_TR_OFF);
6175
6176 /*
6177 * If this is shared segment non 0 softlockcnt
6178 * means locked pages are still in use.
6179 */
6180 if (svd->type == MAP_SHARED) {
6181 return (EAGAIN);
6182 }
6183
6184 /*
6185 * Since we do have the segvn writers lock nobody can fill
6186 * the cache with entries belonging to this seg during
6187 * the purge. The flush either succeeds or we still have
6188 * pending I/Os.
6189 */
6190 segvn_purge(seg);
6191 if (svd->softlockcnt > 0) {
6192 return (EAGAIN);
6193 }
6194 }
6195
6196 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
6197 ASSERT(svd->amp == NULL);
6198 ASSERT(svd->tr_state == SEGVN_TR_OFF);
6199 hat_leave_region(seg->s_as->a_hat, svd->rcookie,
6200 HAT_REGION_TEXT);
6201 svd->rcookie = HAT_INVALID_REGION_COOKIE;
6202 } else if (svd->tr_state == SEGVN_TR_INIT) {
6203 svd->tr_state = SEGVN_TR_OFF;
6204 } else if (svd->tr_state == SEGVN_TR_ON) {
6205 ASSERT(svd->amp != NULL);
6206 segvn_textunrepl(seg, 1);
6207 ASSERT(svd->amp == NULL && svd->tr_state == SEGVN_TR_OFF);
6208 amp = NULL;
6209 }
6210
6211 /*
6212 * Operation for sub range of existing segment.
6213 */
6214 if (addr != seg->s_base || eaddr != (seg->s_base + seg->s_size)) {
6215 if (szc < seg->s_szc) {
6216 VM_STAT_ADD(segvnvmstats.demoterange[2]);
6217 err = segvn_demote_range(seg, addr, len, SDR_RANGE, 0);
6218 if (err == 0) {
6219 return (IE_RETRY);
6220 }
6221 if (err == ENOMEM) {
6222 return (IE_NOMEM);
6223 }
6224 return (err);
6225 }
6226 if (addr != seg->s_base) {
6227 nseg = segvn_split_seg(seg, addr);
6228 if (eaddr != (nseg->s_base + nseg->s_size)) {
6229 /* eaddr is szc aligned */
6230 (void) segvn_split_seg(nseg, eaddr);
6231 }
6232 return (IE_RETRY);
6233 }
6234 if (eaddr != (seg->s_base + seg->s_size)) {
6235 /* eaddr is szc aligned */
6236 (void) segvn_split_seg(seg, eaddr);
6237 }
6238 return (IE_RETRY);
6239 }
6240
6241 /*
6242 * Break any low level sharing and reset seg->s_szc to 0.
6243 */
6244 if ((err = segvn_clrszc(seg)) != 0) {
6245 if (err == ENOMEM) {
6246 err = IE_NOMEM;
6247 }
6248 return (err);
6249 }
6250 ASSERT(seg->s_szc == 0);
6251
6252 /*
6253 * If the end of the current segment is not pgsz aligned
6254 * then attempt to concatenate with the next segment.
6255 */
6256 if (!IS_P2ALIGNED(eaddr, pgsz)) {
6257 nseg = AS_SEGNEXT(seg->s_as, seg);
6258 if (nseg == NULL || nseg == seg || eaddr != nseg->s_base) {
6259 return (ENOMEM);
6260 }
6261 if (nseg->s_ops != &segvn_ops) {
6262 return (EINVAL);
6263 }
6264 nsvd = (struct segvn_data *)nseg->s_data;
6265 if (nsvd->softlockcnt > 0) {
6266 /*
6267 * If this is shared segment non 0 softlockcnt
6268 * means locked pages are still in use.
6269 */
6270 if (nsvd->type == MAP_SHARED) {
6271 return (EAGAIN);
6272 }
6273 segvn_purge(nseg);
6274 if (nsvd->softlockcnt > 0) {
6275 return (EAGAIN);
6276 }
6277 }
6278 err = segvn_clrszc(nseg);
6279 if (err == ENOMEM) {
6280 err = IE_NOMEM;
6281 }
6282 if (err != 0) {
6283 return (err);
6284 }
6285 ASSERT(nsvd->rcookie == HAT_INVALID_REGION_COOKIE);
6286 err = segvn_concat(seg, nseg, 1);
6287 if (err == -1) {
6288 return (EINVAL);
6289 }
6290 if (err == -2) {
6291 return (IE_NOMEM);
6292 }
6293 return (IE_RETRY);
6294 }
6295
6296 /*
6297 * May need to re-align anon array to
6298 * new szc.
6299 */
6300 if (amp != NULL) {
6301 if (!IS_P2ALIGNED(svd->anon_index, pgcnt)) {
6302 struct anon_hdr *nahp;
6303
6304 ASSERT(svd->type == MAP_PRIVATE);
6305
6306 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
6307 ASSERT(amp->refcnt == 1);
6308 nahp = anon_create(btop(amp->size), ANON_NOSLEEP);
6309 if (nahp == NULL) {
6310 ANON_LOCK_EXIT(&->a_rwlock);
6311 return (IE_NOMEM);
6312 }
6313 if (anon_copy_ptr(amp->ahp, svd->anon_index,
6314 nahp, 0, btop(seg->s_size), ANON_NOSLEEP)) {
6315 anon_release(nahp, btop(amp->size));
6316 ANON_LOCK_EXIT(&->a_rwlock);
6317 return (IE_NOMEM);
6318 }
6319 anon_release(amp->ahp, btop(amp->size));
6320 amp->ahp = nahp;
6321 svd->anon_index = 0;
6322 ANON_LOCK_EXIT(&->a_rwlock);
6323 }
6324 }
6325 if (svd->vp != NULL && szc != 0) {
6326 struct vattr va;
6327 u_offset_t eoffpage = svd->offset;
6328 va.va_mask = AT_SIZE;
6329 eoffpage += seg->s_size;
6330 eoffpage = btopr(eoffpage);
6331 if (VOP_GETATTR(svd->vp, &va, 0, svd->cred, NULL) != 0) {
6332 segvn_setpgsz_getattr_err++;
6333 return (EINVAL);
6334 }
6335 if (btopr(va.va_size) < eoffpage) {
6336 segvn_setpgsz_eof_err++;
6337 return (EINVAL);
6338 }
6339 if (amp != NULL) {
6340 /*
6341 * anon_fill_cow_holes() may call VOP_GETPAGE().
6342 * don't take anon map lock here to avoid holding it
6343 * across VOP_GETPAGE() calls that may call back into
6344 * segvn for klsutering checks. We don't really need
6345 * anon map lock here since it's a private segment and
6346 * we hold as level lock as writers.
6347 */
6348 if ((err = anon_fill_cow_holes(seg, seg->s_base,
6349 amp->ahp, svd->anon_index, svd->vp, svd->offset,
6350 seg->s_size, szc, svd->prot, svd->vpage,
6351 svd->cred)) != 0) {
6352 return (EINVAL);
6353 }
6354 }
6355 segvn_setvnode_mpss(svd->vp);
6356 }
6357
6358 if (amp != NULL) {
6359 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
6360 if (svd->type == MAP_PRIVATE) {
6361 amp->a_szc = szc;
6362 } else if (szc > amp->a_szc) {
6363 amp->a_szc = szc;
6364 }
6365 ANON_LOCK_EXIT(&->a_rwlock);
6366 }
6367
6368 seg->s_szc = szc;
6369
6370 return (0);
6371 }
6372
6373 static int
segvn_clrszc(struct seg * seg)6374 segvn_clrszc(struct seg *seg)
6375 {
6376 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6377 struct anon_map *amp = svd->amp;
6378 size_t pgsz;
6379 pgcnt_t pages;
6380 int err = 0;
6381 caddr_t a = seg->s_base;
6382 caddr_t ea = a + seg->s_size;
6383 ulong_t an_idx = svd->anon_index;
6384 vnode_t *vp = svd->vp;
6385 struct vpage *vpage = svd->vpage;
6386 page_t *anon_pl[1 + 1], *pp;
6387 struct anon *ap, *oldap;
6388 uint_t prot = svd->prot, vpprot;
6389 int pageflag = 0;
6390
6391 ASSERT(AS_WRITE_HELD(seg->s_as) ||
6392 SEGVN_WRITE_HELD(seg->s_as, &svd->lock));
6393 ASSERT(svd->softlockcnt == 0);
6394
6395 if (vp == NULL && amp == NULL) {
6396 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
6397 seg->s_szc = 0;
6398 return (0);
6399 }
6400
6401 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
6402 ASSERT(svd->amp == NULL);
6403 ASSERT(svd->tr_state == SEGVN_TR_OFF);
6404 hat_leave_region(seg->s_as->a_hat, svd->rcookie,
6405 HAT_REGION_TEXT);
6406 svd->rcookie = HAT_INVALID_REGION_COOKIE;
6407 } else if (svd->tr_state == SEGVN_TR_ON) {
6408 ASSERT(svd->amp != NULL);
6409 segvn_textunrepl(seg, 1);
6410 ASSERT(svd->amp == NULL && svd->tr_state == SEGVN_TR_OFF);
6411 amp = NULL;
6412 } else {
6413 if (svd->tr_state != SEGVN_TR_OFF) {
6414 ASSERT(svd->tr_state == SEGVN_TR_INIT);
6415 svd->tr_state = SEGVN_TR_OFF;
6416 }
6417
6418 /*
6419 * do HAT_UNLOAD_UNMAP since we are changing the pagesize.
6420 * unload argument is 0 when we are freeing the segment
6421 * and unload was already done.
6422 */
6423 hat_unload(seg->s_as->a_hat, seg->s_base, seg->s_size,
6424 HAT_UNLOAD_UNMAP);
6425 }
6426
6427 if (amp == NULL || svd->type == MAP_SHARED) {
6428 seg->s_szc = 0;
6429 return (0);
6430 }
6431
6432 pgsz = page_get_pagesize(seg->s_szc);
6433 pages = btop(pgsz);
6434
6435 /*
6436 * XXX anon rwlock is not really needed because this is a
6437 * private segment and we are writers.
6438 */
6439 ANON_LOCK_ENTER(&->a_rwlock, RW_WRITER);
6440
6441 for (; a < ea; a += pgsz, an_idx += pages) {
6442 if ((oldap = anon_get_ptr(amp->ahp, an_idx)) != NULL) {
6443 ASSERT(vpage != NULL || svd->pageprot == 0);
6444 if (vpage != NULL) {
6445 ASSERT(sameprot(seg, a, pgsz));
6446 prot = VPP_PROT(vpage);
6447 pageflag = VPP_ISPPLOCK(vpage) ? LOCK_PAGE : 0;
6448 }
6449 if (seg->s_szc != 0) {
6450 ASSERT(vp == NULL || anon_pages(amp->ahp,
6451 an_idx, pages) == pages);
6452 if ((err = anon_map_demotepages(amp, an_idx,
6453 seg, a, prot, vpage, svd->cred)) != 0) {
6454 goto out;
6455 }
6456 } else {
6457 if (oldap->an_refcnt == 1) {
6458 continue;
6459 }
6460 if ((err = anon_getpage(&oldap, &vpprot,
6461 anon_pl, PAGESIZE, seg, a, S_READ,
6462 svd->cred))) {
6463 goto out;
6464 }
6465 if ((pp = anon_private(&ap, seg, a, prot,
6466 anon_pl[0], pageflag, svd->cred)) == NULL) {
6467 err = ENOMEM;
6468 goto out;
6469 }
6470 anon_decref(oldap);
6471 (void) anon_set_ptr(amp->ahp, an_idx, ap,
6472 ANON_SLEEP);
6473 page_unlock(pp);
6474 }
6475 }
6476 vpage = (vpage == NULL) ? NULL : vpage + pages;
6477 }
6478
6479 amp->a_szc = 0;
6480 seg->s_szc = 0;
6481 out:
6482 ANON_LOCK_EXIT(&->a_rwlock);
6483 return (err);
6484 }
6485
6486 static int
segvn_claim_pages(struct seg * seg,struct vpage * svp,u_offset_t off,ulong_t anon_idx,uint_t prot)6487 segvn_claim_pages(
6488 struct seg *seg,
6489 struct vpage *svp,
6490 u_offset_t off,
6491 ulong_t anon_idx,
6492 uint_t prot)
6493 {
6494 pgcnt_t pgcnt = page_get_pagecnt(seg->s_szc);
6495 size_t ppasize = (pgcnt + 1) * sizeof (page_t *);
6496 page_t **ppa;
6497 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6498 struct anon_map *amp = svd->amp;
6499 struct vpage *evp = svp + pgcnt;
6500 caddr_t addr = ((uintptr_t)(svp - svd->vpage) << PAGESHIFT)
6501 + seg->s_base;
6502 struct anon *ap;
6503 struct vnode *vp = svd->vp;
6504 page_t *pp;
6505 pgcnt_t pg_idx, i;
6506 int err = 0;
6507 anoff_t aoff;
6508 int anon = (amp != NULL) ? 1 : 0;
6509
6510 ASSERT(svd->type == MAP_PRIVATE);
6511 ASSERT(svd->vpage != NULL);
6512 ASSERT(seg->s_szc != 0);
6513 ASSERT(IS_P2ALIGNED(pgcnt, pgcnt));
6514 ASSERT(amp == NULL || IS_P2ALIGNED(anon_idx, pgcnt));
6515 ASSERT(sameprot(seg, addr, pgcnt << PAGESHIFT));
6516
6517 if (VPP_PROT(svp) == prot)
6518 return (1);
6519 if (!((VPP_PROT(svp) ^ prot) & PROT_WRITE))
6520 return (1);
6521
6522 ppa = kmem_alloc(ppasize, KM_SLEEP);
6523 if (anon && vp != NULL) {
6524 if (anon_get_ptr(amp->ahp, anon_idx) == NULL) {
6525 anon = 0;
6526 ASSERT(!anon_pages(amp->ahp, anon_idx, pgcnt));
6527 }
6528 ASSERT(!anon ||
6529 anon_pages(amp->ahp, anon_idx, pgcnt) == pgcnt);
6530 }
6531
6532 for (*ppa = NULL, pg_idx = 0; svp < evp; svp++, anon_idx++) {
6533 if (!VPP_ISPPLOCK(svp))
6534 continue;
6535 if (anon) {
6536 ap = anon_get_ptr(amp->ahp, anon_idx);
6537 if (ap == NULL) {
6538 panic("segvn_claim_pages: no anon slot");
6539 }
6540 swap_xlate(ap, &vp, &aoff);
6541 off = (u_offset_t)aoff;
6542 }
6543 ASSERT(vp != NULL);
6544 if ((pp = page_lookup(vp,
6545 (u_offset_t)off, SE_SHARED)) == NULL) {
6546 panic("segvn_claim_pages: no page");
6547 }
6548 ppa[pg_idx++] = pp;
6549 off += PAGESIZE;
6550 }
6551
6552 if (ppa[0] == NULL) {
6553 kmem_free(ppa, ppasize);
6554 return (1);
6555 }
6556
6557 ASSERT(pg_idx <= pgcnt);
6558 ppa[pg_idx] = NULL;
6559
6560
6561 /* Find each large page within ppa, and adjust its claim */
6562
6563 /* Does ppa cover a single large page? */
6564 if (ppa[0]->p_szc == seg->s_szc) {
6565 if (prot & PROT_WRITE)
6566 err = page_addclaim_pages(ppa);
6567 else
6568 err = page_subclaim_pages(ppa);
6569 } else {
6570 for (i = 0; ppa[i]; i += pgcnt) {
6571 ASSERT(IS_P2ALIGNED(page_pptonum(ppa[i]), pgcnt));
6572 if (prot & PROT_WRITE)
6573 err = page_addclaim_pages(&ppa[i]);
6574 else
6575 err = page_subclaim_pages(&ppa[i]);
6576 if (err == 0)
6577 break;
6578 }
6579 }
6580
6581 for (i = 0; i < pg_idx; i++) {
6582 ASSERT(ppa[i] != NULL);
6583 page_unlock(ppa[i]);
6584 }
6585
6586 kmem_free(ppa, ppasize);
6587 return (err);
6588 }
6589
6590 /*
6591 * Returns right (upper address) segment if split occurred.
6592 * If the address is equal to the beginning or end of its segment it returns
6593 * the current segment.
6594 */
6595 static struct seg *
segvn_split_seg(struct seg * seg,caddr_t addr)6596 segvn_split_seg(struct seg *seg, caddr_t addr)
6597 {
6598 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6599 struct seg *nseg;
6600 size_t nsize;
6601 struct segvn_data *nsvd;
6602
6603 ASSERT(AS_WRITE_HELD(seg->s_as));
6604 ASSERT(svd->tr_state == SEGVN_TR_OFF);
6605
6606 ASSERT(addr >= seg->s_base);
6607 ASSERT(addr <= seg->s_base + seg->s_size);
6608 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
6609
6610 if (addr == seg->s_base || addr == seg->s_base + seg->s_size)
6611 return (seg);
6612
6613 nsize = seg->s_base + seg->s_size - addr;
6614 seg->s_size = addr - seg->s_base;
6615 nseg = seg_alloc(seg->s_as, addr, nsize);
6616 ASSERT(nseg != NULL);
6617 nseg->s_ops = seg->s_ops;
6618 nsvd = kmem_cache_alloc(segvn_cache, KM_SLEEP);
6619 nseg->s_data = (void *)nsvd;
6620 nseg->s_szc = seg->s_szc;
6621 *nsvd = *svd;
6622 ASSERT(nsvd->rcookie == HAT_INVALID_REGION_COOKIE);
6623 nsvd->seg = nseg;
6624 rw_init(&nsvd->lock, NULL, RW_DEFAULT, NULL);
6625
6626 if (nsvd->vp != NULL) {
6627 VN_HOLD(nsvd->vp);
6628 nsvd->offset = svd->offset +
6629 (uintptr_t)(nseg->s_base - seg->s_base);
6630 if (nsvd->type == MAP_SHARED)
6631 lgrp_shm_policy_init(NULL, nsvd->vp);
6632 } else {
6633 /*
6634 * The offset for an anonymous segment has no signifigance in
6635 * terms of an offset into a file. If we were to use the above
6636 * calculation instead, the structures read out of
6637 * /proc/<pid>/xmap would be more difficult to decipher since
6638 * it would be unclear whether two seemingly contiguous
6639 * prxmap_t structures represented different segments or a
6640 * single segment that had been split up into multiple prxmap_t
6641 * structures (e.g. if some part of the segment had not yet
6642 * been faulted in).
6643 */
6644 nsvd->offset = 0;
6645 }
6646
6647 ASSERT(svd->softlockcnt == 0);
6648 ASSERT(svd->softlockcnt_sbase == 0);
6649 ASSERT(svd->softlockcnt_send == 0);
6650 crhold(svd->cred);
6651
6652 if (svd->vpage != NULL) {
6653 size_t bytes = vpgtob(seg_pages(seg));
6654 size_t nbytes = vpgtob(seg_pages(nseg));
6655 struct vpage *ovpage = svd->vpage;
6656
6657 svd->vpage = kmem_alloc(bytes, KM_SLEEP);
6658 bcopy(ovpage, svd->vpage, bytes);
6659 nsvd->vpage = kmem_alloc(nbytes, KM_SLEEP);
6660 bcopy(ovpage + seg_pages(seg), nsvd->vpage, nbytes);
6661 kmem_free(ovpage, bytes + nbytes);
6662 }
6663 if (svd->amp != NULL && svd->type == MAP_PRIVATE) {
6664 struct anon_map *oamp = svd->amp, *namp;
6665 struct anon_hdr *nahp;
6666
6667 ANON_LOCK_ENTER(&oamp->a_rwlock, RW_WRITER);
6668 ASSERT(oamp->refcnt == 1);
6669 nahp = anon_create(btop(seg->s_size), ANON_SLEEP);
6670 (void) anon_copy_ptr(oamp->ahp, svd->anon_index,
6671 nahp, 0, btop(seg->s_size), ANON_SLEEP);
6672
6673 namp = anonmap_alloc(nseg->s_size, 0, ANON_SLEEP);
6674 namp->a_szc = nseg->s_szc;
6675 (void) anon_copy_ptr(oamp->ahp,
6676 svd->anon_index + btop(seg->s_size),
6677 namp->ahp, 0, btop(nseg->s_size), ANON_SLEEP);
6678 anon_release(oamp->ahp, btop(oamp->size));
6679 oamp->ahp = nahp;
6680 oamp->size = seg->s_size;
6681 svd->anon_index = 0;
6682 nsvd->amp = namp;
6683 nsvd->anon_index = 0;
6684 ANON_LOCK_EXIT(&oamp->a_rwlock);
6685 } else if (svd->amp != NULL) {
6686 pgcnt_t pgcnt = page_get_pagecnt(seg->s_szc);
6687 ASSERT(svd->amp == nsvd->amp);
6688 ASSERT(seg->s_szc <= svd->amp->a_szc);
6689 nsvd->anon_index = svd->anon_index + seg_pages(seg);
6690 ASSERT(IS_P2ALIGNED(nsvd->anon_index, pgcnt));
6691 ANON_LOCK_ENTER(&svd->amp->a_rwlock, RW_WRITER);
6692 svd->amp->refcnt++;
6693 ANON_LOCK_EXIT(&svd->amp->a_rwlock);
6694 }
6695
6696 /*
6697 * Split the amount of swap reserved.
6698 */
6699 if (svd->swresv) {
6700 /*
6701 * For MAP_NORESERVE, only allocate swap reserve for pages
6702 * being used. Other segments get enough to cover whole
6703 * segment.
6704 */
6705 if (svd->flags & MAP_NORESERVE) {
6706 size_t oswresv;
6707
6708 ASSERT(svd->amp);
6709 oswresv = svd->swresv;
6710 svd->swresv = ptob(anon_pages(svd->amp->ahp,
6711 svd->anon_index, btop(seg->s_size)));
6712 nsvd->swresv = ptob(anon_pages(nsvd->amp->ahp,
6713 nsvd->anon_index, btop(nseg->s_size)));
6714 ASSERT(oswresv >= (svd->swresv + nsvd->swresv));
6715 } else {
6716 if (svd->pageswap) {
6717 svd->swresv = segvn_count_swap_by_vpages(seg);
6718 ASSERT(nsvd->swresv >= svd->swresv);
6719 nsvd->swresv -= svd->swresv;
6720 } else {
6721 ASSERT(svd->swresv == seg->s_size +
6722 nseg->s_size);
6723 svd->swresv = seg->s_size;
6724 nsvd->swresv = nseg->s_size;
6725 }
6726 }
6727 }
6728
6729 return (nseg);
6730 }
6731
6732 /*
6733 * called on memory operations (unmap, setprot, setpagesize) for a subset
6734 * of a large page segment to either demote the memory range (SDR_RANGE)
6735 * or the ends (SDR_END) by addr/len.
6736 *
6737 * returns 0 on success. returns errno, including ENOMEM, on failure.
6738 */
6739 static int
segvn_demote_range(struct seg * seg,caddr_t addr,size_t len,int flag,uint_t szcvec)6740 segvn_demote_range(
6741 struct seg *seg,
6742 caddr_t addr,
6743 size_t len,
6744 int flag,
6745 uint_t szcvec)
6746 {
6747 caddr_t eaddr = addr + len;
6748 caddr_t lpgaddr, lpgeaddr;
6749 struct seg *nseg;
6750 struct seg *badseg1 = NULL;
6751 struct seg *badseg2 = NULL;
6752 size_t pgsz;
6753 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6754 int err;
6755 uint_t szc = seg->s_szc;
6756 uint_t tszcvec;
6757
6758 ASSERT(AS_WRITE_HELD(seg->s_as));
6759 ASSERT(svd->tr_state == SEGVN_TR_OFF);
6760 ASSERT(szc != 0);
6761 pgsz = page_get_pagesize(szc);
6762 ASSERT(seg->s_base != addr || seg->s_size != len);
6763 ASSERT(addr >= seg->s_base && eaddr <= seg->s_base + seg->s_size);
6764 ASSERT(svd->softlockcnt == 0);
6765 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
6766 ASSERT(szcvec == 0 || (flag == SDR_END && svd->type == MAP_SHARED));
6767
6768 CALC_LPG_REGION(pgsz, seg, addr, len, lpgaddr, lpgeaddr);
6769 ASSERT(flag == SDR_RANGE || eaddr < lpgeaddr || addr > lpgaddr);
6770 if (flag == SDR_RANGE) {
6771 /* demote entire range */
6772 badseg1 = nseg = segvn_split_seg(seg, lpgaddr);
6773 (void) segvn_split_seg(nseg, lpgeaddr);
6774 ASSERT(badseg1->s_base == lpgaddr);
6775 ASSERT(badseg1->s_size == lpgeaddr - lpgaddr);
6776 } else if (addr != lpgaddr) {
6777 ASSERT(flag == SDR_END);
6778 badseg1 = nseg = segvn_split_seg(seg, lpgaddr);
6779 if (eaddr != lpgeaddr && eaddr > lpgaddr + pgsz &&
6780 eaddr < lpgaddr + 2 * pgsz) {
6781 (void) segvn_split_seg(nseg, lpgeaddr);
6782 ASSERT(badseg1->s_base == lpgaddr);
6783 ASSERT(badseg1->s_size == 2 * pgsz);
6784 } else {
6785 nseg = segvn_split_seg(nseg, lpgaddr + pgsz);
6786 ASSERT(badseg1->s_base == lpgaddr);
6787 ASSERT(badseg1->s_size == pgsz);
6788 if (eaddr != lpgeaddr && eaddr > lpgaddr + pgsz) {
6789 ASSERT(lpgeaddr - lpgaddr > 2 * pgsz);
6790 nseg = segvn_split_seg(nseg, lpgeaddr - pgsz);
6791 badseg2 = nseg;
6792 (void) segvn_split_seg(nseg, lpgeaddr);
6793 ASSERT(badseg2->s_base == lpgeaddr - pgsz);
6794 ASSERT(badseg2->s_size == pgsz);
6795 }
6796 }
6797 } else {
6798 ASSERT(flag == SDR_END);
6799 ASSERT(eaddr < lpgeaddr);
6800 badseg1 = nseg = segvn_split_seg(seg, lpgeaddr - pgsz);
6801 (void) segvn_split_seg(nseg, lpgeaddr);
6802 ASSERT(badseg1->s_base == lpgeaddr - pgsz);
6803 ASSERT(badseg1->s_size == pgsz);
6804 }
6805
6806 ASSERT(badseg1 != NULL);
6807 ASSERT(badseg1->s_szc == szc);
6808 ASSERT(flag == SDR_RANGE || badseg1->s_size == pgsz ||
6809 badseg1->s_size == 2 * pgsz);
6810 ASSERT(sameprot(badseg1, badseg1->s_base, pgsz));
6811 ASSERT(badseg1->s_size == pgsz ||
6812 sameprot(badseg1, badseg1->s_base + pgsz, pgsz));
6813 if (err = segvn_clrszc(badseg1)) {
6814 return (err);
6815 }
6816 ASSERT(badseg1->s_szc == 0);
6817
6818 if (szc > 1 && (tszcvec = P2PHASE(szcvec, 1 << szc)) > 1) {
6819 uint_t tszc = highbit(tszcvec) - 1;
6820 caddr_t ta = MAX(addr, badseg1->s_base);
6821 caddr_t te;
6822 size_t tpgsz = page_get_pagesize(tszc);
6823
6824 ASSERT(svd->type == MAP_SHARED);
6825 ASSERT(flag == SDR_END);
6826 ASSERT(tszc < szc && tszc > 0);
6827
6828 if (eaddr > badseg1->s_base + badseg1->s_size) {
6829 te = badseg1->s_base + badseg1->s_size;
6830 } else {
6831 te = eaddr;
6832 }
6833
6834 ASSERT(ta <= te);
6835 badseg1->s_szc = tszc;
6836 if (!IS_P2ALIGNED(ta, tpgsz) || !IS_P2ALIGNED(te, tpgsz)) {
6837 if (badseg2 != NULL) {
6838 err = segvn_demote_range(badseg1, ta, te - ta,
6839 SDR_END, tszcvec);
6840 if (err != 0) {
6841 return (err);
6842 }
6843 } else {
6844 return (segvn_demote_range(badseg1, ta,
6845 te - ta, SDR_END, tszcvec));
6846 }
6847 }
6848 }
6849
6850 if (badseg2 == NULL)
6851 return (0);
6852 ASSERT(badseg2->s_szc == szc);
6853 ASSERT(badseg2->s_size == pgsz);
6854 ASSERT(sameprot(badseg2, badseg2->s_base, badseg2->s_size));
6855 if (err = segvn_clrszc(badseg2)) {
6856 return (err);
6857 }
6858 ASSERT(badseg2->s_szc == 0);
6859
6860 if (szc > 1 && (tszcvec = P2PHASE(szcvec, 1 << szc)) > 1) {
6861 uint_t tszc = highbit(tszcvec) - 1;
6862 size_t tpgsz = page_get_pagesize(tszc);
6863
6864 ASSERT(svd->type == MAP_SHARED);
6865 ASSERT(flag == SDR_END);
6866 ASSERT(tszc < szc && tszc > 0);
6867 ASSERT(badseg2->s_base > addr);
6868 ASSERT(eaddr > badseg2->s_base);
6869 ASSERT(eaddr < badseg2->s_base + badseg2->s_size);
6870
6871 badseg2->s_szc = tszc;
6872 if (!IS_P2ALIGNED(eaddr, tpgsz)) {
6873 return (segvn_demote_range(badseg2, badseg2->s_base,
6874 eaddr - badseg2->s_base, SDR_END, tszcvec));
6875 }
6876 }
6877
6878 return (0);
6879 }
6880
6881 static int
segvn_checkprot(struct seg * seg,caddr_t addr,size_t len,uint_t prot)6882 segvn_checkprot(struct seg *seg, caddr_t addr, size_t len, uint_t prot)
6883 {
6884 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6885 struct vpage *vp, *evp;
6886
6887 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
6888
6889 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
6890 /*
6891 * If segment protection can be used, simply check against them.
6892 */
6893 if (svd->pageprot == 0) {
6894 int err;
6895
6896 err = ((svd->prot & prot) != prot) ? EACCES : 0;
6897 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6898 return (err);
6899 }
6900
6901 /*
6902 * Have to check down to the vpage level.
6903 */
6904 evp = &svd->vpage[seg_page(seg, addr + len)];
6905 for (vp = &svd->vpage[seg_page(seg, addr)]; vp < evp; vp++) {
6906 if ((VPP_PROT(vp) & prot) != prot) {
6907 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6908 return (EACCES);
6909 }
6910 }
6911 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6912 return (0);
6913 }
6914
6915 static int
segvn_getprot(struct seg * seg,caddr_t addr,size_t len,uint_t * protv)6916 segvn_getprot(struct seg *seg, caddr_t addr, size_t len, uint_t *protv)
6917 {
6918 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6919 size_t pgno = seg_page(seg, addr + len) - seg_page(seg, addr) + 1;
6920
6921 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
6922
6923 if (pgno != 0) {
6924 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
6925 if (svd->pageprot == 0) {
6926 do {
6927 protv[--pgno] = svd->prot;
6928 } while (pgno != 0);
6929 } else {
6930 size_t pgoff = seg_page(seg, addr);
6931
6932 do {
6933 pgno--;
6934 protv[pgno] = VPP_PROT(&svd->vpage[pgno+pgoff]);
6935 } while (pgno != 0);
6936 }
6937 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
6938 }
6939 return (0);
6940 }
6941
6942 static u_offset_t
segvn_getoffset(struct seg * seg,caddr_t addr)6943 segvn_getoffset(struct seg *seg, caddr_t addr)
6944 {
6945 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6946
6947 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
6948
6949 return (svd->offset + (uintptr_t)(addr - seg->s_base));
6950 }
6951
6952 /*ARGSUSED*/
6953 static int
segvn_gettype(struct seg * seg,caddr_t addr)6954 segvn_gettype(struct seg *seg, caddr_t addr)
6955 {
6956 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6957
6958 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
6959
6960 return (svd->type | (svd->flags & (MAP_NORESERVE | MAP_TEXT |
6961 MAP_INITDATA)));
6962 }
6963
6964 /*ARGSUSED*/
6965 static int
segvn_getvp(struct seg * seg,caddr_t addr,struct vnode ** vpp)6966 segvn_getvp(struct seg *seg, caddr_t addr, struct vnode **vpp)
6967 {
6968 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6969
6970 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
6971
6972 *vpp = svd->vp;
6973 return (0);
6974 }
6975
6976 /*
6977 * Check to see if it makes sense to do kluster/read ahead to
6978 * addr + delta relative to the mapping at addr. We assume here
6979 * that delta is a signed PAGESIZE'd multiple (which can be negative).
6980 *
6981 * For segvn, we currently "approve" of the action if we are
6982 * still in the segment and it maps from the same vp/off,
6983 * or if the advice stored in segvn_data or vpages allows it.
6984 * Currently, klustering is not allowed only if MADV_RANDOM is set.
6985 */
6986 static int
segvn_kluster(struct seg * seg,caddr_t addr,ssize_t delta)6987 segvn_kluster(struct seg *seg, caddr_t addr, ssize_t delta)
6988 {
6989 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
6990 struct anon *oap, *ap;
6991 ssize_t pd;
6992 size_t page;
6993 struct vnode *vp1, *vp2;
6994 u_offset_t off1, off2;
6995 struct anon_map *amp;
6996
6997 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
6998 ASSERT(AS_WRITE_HELD(seg->s_as) ||
6999 SEGVN_LOCK_HELD(seg->s_as, &svd->lock));
7000
7001 if (addr + delta < seg->s_base ||
7002 addr + delta >= (seg->s_base + seg->s_size))
7003 return (-1); /* exceeded segment bounds */
7004
7005 pd = delta / (ssize_t)PAGESIZE; /* divide to preserve sign bit */
7006 page = seg_page(seg, addr);
7007
7008 /*
7009 * Check to see if either of the pages addr or addr + delta
7010 * have advice set that prevents klustering (if MADV_RANDOM advice
7011 * is set for entire segment, or MADV_SEQUENTIAL is set and delta
7012 * is negative).
7013 */
7014 if (svd->advice == MADV_RANDOM ||
7015 svd->advice == MADV_SEQUENTIAL && delta < 0)
7016 return (-1);
7017 else if (svd->pageadvice && svd->vpage) {
7018 struct vpage *bvpp, *evpp;
7019
7020 bvpp = &svd->vpage[page];
7021 evpp = &svd->vpage[page + pd];
7022 if (VPP_ADVICE(bvpp) == MADV_RANDOM ||
7023 VPP_ADVICE(evpp) == MADV_SEQUENTIAL && delta < 0)
7024 return (-1);
7025 if (VPP_ADVICE(bvpp) != VPP_ADVICE(evpp) &&
7026 VPP_ADVICE(evpp) == MADV_RANDOM)
7027 return (-1);
7028 }
7029
7030 if (svd->type == MAP_SHARED)
7031 return (0); /* shared mapping - all ok */
7032
7033 if ((amp = svd->amp) == NULL)
7034 return (0); /* off original vnode */
7035
7036 page += svd->anon_index;
7037
7038 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
7039
7040 oap = anon_get_ptr(amp->ahp, page);
7041 ap = anon_get_ptr(amp->ahp, page + pd);
7042
7043 ANON_LOCK_EXIT(&->a_rwlock);
7044
7045 if ((oap == NULL && ap != NULL) || (oap != NULL && ap == NULL)) {
7046 return (-1); /* one with and one without an anon */
7047 }
7048
7049 if (oap == NULL) { /* implies that ap == NULL */
7050 return (0); /* off original vnode */
7051 }
7052
7053 /*
7054 * Now we know we have two anon pointers - check to
7055 * see if they happen to be properly allocated.
7056 */
7057
7058 /*
7059 * XXX We cheat here and don't lock the anon slots. We can't because
7060 * we may have been called from the anon layer which might already
7061 * have locked them. We are holding a refcnt on the slots so they
7062 * can't disappear. The worst that will happen is we'll get the wrong
7063 * names (vp, off) for the slots and make a poor klustering decision.
7064 */
7065 swap_xlate(ap, &vp1, &off1);
7066 swap_xlate(oap, &vp2, &off2);
7067
7068
7069 if (!VOP_CMP(vp1, vp2, NULL) || off1 - off2 != delta)
7070 return (-1);
7071 return (0);
7072 }
7073
7074 /*
7075 * Swap the pages of seg out to secondary storage, returning the
7076 * number of bytes of storage freed.
7077 *
7078 * The basic idea is first to unload all translations and then to call
7079 * VOP_PUTPAGE() for all newly-unmapped pages, to push them out to the
7080 * swap device. Pages to which other segments have mappings will remain
7081 * mapped and won't be swapped. Our caller (as_swapout) has already
7082 * performed the unloading step.
7083 *
7084 * The value returned is intended to correlate well with the process's
7085 * memory requirements. However, there are some caveats:
7086 * 1) When given a shared segment as argument, this routine will
7087 * only succeed in swapping out pages for the last sharer of the
7088 * segment. (Previous callers will only have decremented mapping
7089 * reference counts.)
7090 * 2) We assume that the hat layer maintains a large enough translation
7091 * cache to capture process reference patterns.
7092 */
7093 static size_t
segvn_swapout(struct seg * seg)7094 segvn_swapout(struct seg *seg)
7095 {
7096 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
7097 struct anon_map *amp;
7098 pgcnt_t pgcnt = 0;
7099 pgcnt_t npages;
7100 pgcnt_t page;
7101 ulong_t anon_index;
7102
7103 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
7104
7105 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
7106 /*
7107 * Find pages unmapped by our caller and force them
7108 * out to the virtual swap device.
7109 */
7110 if ((amp = svd->amp) != NULL)
7111 anon_index = svd->anon_index;
7112 npages = seg->s_size >> PAGESHIFT;
7113 for (page = 0; page < npages; page++) {
7114 page_t *pp;
7115 struct anon *ap;
7116 struct vnode *vp;
7117 u_offset_t off;
7118 anon_sync_obj_t cookie;
7119
7120 /*
7121 * Obtain <vp, off> pair for the page, then look it up.
7122 *
7123 * Note that this code is willing to consider regular
7124 * pages as well as anon pages. Is this appropriate here?
7125 */
7126 ap = NULL;
7127 if (amp != NULL) {
7128 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
7129 if (anon_array_try_enter(amp, anon_index + page,
7130 &cookie)) {
7131 ANON_LOCK_EXIT(&->a_rwlock);
7132 continue;
7133 }
7134 ap = anon_get_ptr(amp->ahp, anon_index + page);
7135 if (ap != NULL) {
7136 swap_xlate(ap, &vp, &off);
7137 } else {
7138 vp = svd->vp;
7139 off = svd->offset + ptob(page);
7140 }
7141 anon_array_exit(&cookie);
7142 ANON_LOCK_EXIT(&->a_rwlock);
7143 } else {
7144 vp = svd->vp;
7145 off = svd->offset + ptob(page);
7146 }
7147 if (vp == NULL) { /* untouched zfod page */
7148 ASSERT(ap == NULL);
7149 continue;
7150 }
7151
7152 pp = page_lookup_nowait(vp, off, SE_SHARED);
7153 if (pp == NULL)
7154 continue;
7155
7156
7157 /*
7158 * Examine the page to see whether it can be tossed out,
7159 * keeping track of how many we've found.
7160 */
7161 if (!page_tryupgrade(pp)) {
7162 /*
7163 * If the page has an i/o lock and no mappings,
7164 * it's very likely that the page is being
7165 * written out as a result of klustering.
7166 * Assume this is so and take credit for it here.
7167 */
7168 if (!page_io_trylock(pp)) {
7169 if (!hat_page_is_mapped(pp))
7170 pgcnt++;
7171 } else {
7172 page_io_unlock(pp);
7173 }
7174 page_unlock(pp);
7175 continue;
7176 }
7177 ASSERT(!page_iolock_assert(pp));
7178
7179
7180 /*
7181 * Skip if page is locked or has mappings.
7182 * We don't need the page_struct_lock to look at lckcnt
7183 * and cowcnt because the page is exclusive locked.
7184 */
7185 if (pp->p_lckcnt != 0 || pp->p_cowcnt != 0 ||
7186 hat_page_is_mapped(pp)) {
7187 page_unlock(pp);
7188 continue;
7189 }
7190
7191 /*
7192 * dispose skips large pages so try to demote first.
7193 */
7194 if (pp->p_szc != 0 && !page_try_demote_pages(pp)) {
7195 page_unlock(pp);
7196 /*
7197 * XXX should skip the remaining page_t's of this
7198 * large page.
7199 */
7200 continue;
7201 }
7202
7203 ASSERT(pp->p_szc == 0);
7204
7205 /*
7206 * No longer mapped -- we can toss it out. How
7207 * we do so depends on whether or not it's dirty.
7208 */
7209 if (hat_ismod(pp) && pp->p_vnode) {
7210 /*
7211 * We must clean the page before it can be
7212 * freed. Setting B_FREE will cause pvn_done
7213 * to free the page when the i/o completes.
7214 * XXX: This also causes it to be accounted
7215 * as a pageout instead of a swap: need
7216 * B_SWAPOUT bit to use instead of B_FREE.
7217 *
7218 * Hold the vnode before releasing the page lock
7219 * to prevent it from being freed and re-used by
7220 * some other thread.
7221 */
7222 VN_HOLD(vp);
7223 page_unlock(pp);
7224
7225 /*
7226 * Queue all i/o requests for the pageout thread
7227 * to avoid saturating the pageout devices.
7228 */
7229 if (!queue_io_request(vp, off))
7230 VN_RELE(vp);
7231 } else {
7232 /*
7233 * The page was clean, free it.
7234 *
7235 * XXX: Can we ever encounter modified pages
7236 * with no associated vnode here?
7237 */
7238 ASSERT(pp->p_vnode != NULL);
7239 /*LINTED: constant in conditional context*/
7240 VN_DISPOSE(pp, B_FREE, 0, kcred);
7241 }
7242
7243 /*
7244 * Credit now even if i/o is in progress.
7245 */
7246 pgcnt++;
7247 }
7248 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7249
7250 /*
7251 * Wakeup pageout to initiate i/o on all queued requests.
7252 */
7253 cv_signal_pageout();
7254 return (ptob(pgcnt));
7255 }
7256
7257 /*
7258 * Synchronize primary storage cache with real object in virtual memory.
7259 *
7260 * XXX - Anonymous pages should not be sync'ed out at all.
7261 */
7262 static int
segvn_sync(struct seg * seg,caddr_t addr,size_t len,int attr,uint_t flags)7263 segvn_sync(struct seg *seg, caddr_t addr, size_t len, int attr, uint_t flags)
7264 {
7265 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
7266 struct vpage *vpp;
7267 page_t *pp;
7268 u_offset_t offset;
7269 struct vnode *vp;
7270 u_offset_t off;
7271 caddr_t eaddr;
7272 int bflags;
7273 int err = 0;
7274 int segtype;
7275 int pageprot;
7276 int prot;
7277 ulong_t anon_index;
7278 struct anon_map *amp;
7279 struct anon *ap;
7280 anon_sync_obj_t cookie;
7281
7282 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
7283
7284 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
7285
7286 if (svd->softlockcnt > 0) {
7287 /*
7288 * If this is shared segment non 0 softlockcnt
7289 * means locked pages are still in use.
7290 */
7291 if (svd->type == MAP_SHARED) {
7292 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7293 return (EAGAIN);
7294 }
7295
7296 /*
7297 * flush all pages from seg cache
7298 * otherwise we may deadlock in swap_putpage
7299 * for B_INVAL page (4175402).
7300 *
7301 * Even if we grab segvn WRITER's lock
7302 * here, there might be another thread which could've
7303 * successfully performed lookup/insert just before
7304 * we acquired the lock here. So, grabbing either
7305 * lock here is of not much use. Until we devise
7306 * a strategy at upper layers to solve the
7307 * synchronization issues completely, we expect
7308 * applications to handle this appropriately.
7309 */
7310 segvn_purge(seg);
7311 if (svd->softlockcnt > 0) {
7312 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7313 return (EAGAIN);
7314 }
7315 } else if (svd->type == MAP_SHARED && svd->amp != NULL &&
7316 svd->amp->a_softlockcnt > 0) {
7317 /*
7318 * Try to purge this amp's entries from pcache. It will
7319 * succeed only if other segments that share the amp have no
7320 * outstanding softlock's.
7321 */
7322 segvn_purge(seg);
7323 if (svd->amp->a_softlockcnt > 0 || svd->softlockcnt > 0) {
7324 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7325 return (EAGAIN);
7326 }
7327 }
7328
7329 vpp = svd->vpage;
7330 offset = svd->offset + (uintptr_t)(addr - seg->s_base);
7331 bflags = ((flags & MS_ASYNC) ? B_ASYNC : 0) |
7332 ((flags & MS_INVALIDATE) ? B_INVAL : 0);
7333
7334 if (attr) {
7335 pageprot = attr & ~(SHARED|PRIVATE);
7336 segtype = (attr & SHARED) ? MAP_SHARED : MAP_PRIVATE;
7337
7338 /*
7339 * We are done if the segment types don't match
7340 * or if we have segment level protections and
7341 * they don't match.
7342 */
7343 if (svd->type != segtype) {
7344 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7345 return (0);
7346 }
7347 if (vpp == NULL) {
7348 if (svd->prot != pageprot) {
7349 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7350 return (0);
7351 }
7352 prot = svd->prot;
7353 } else
7354 vpp = &svd->vpage[seg_page(seg, addr)];
7355
7356 } else if (svd->vp && svd->amp == NULL &&
7357 (flags & MS_INVALIDATE) == 0) {
7358
7359 /*
7360 * No attributes, no anonymous pages and MS_INVALIDATE flag
7361 * is not on, just use one big request.
7362 */
7363 err = VOP_PUTPAGE(svd->vp, (offset_t)offset, len,
7364 bflags, svd->cred, NULL);
7365 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7366 return (err);
7367 }
7368
7369 if ((amp = svd->amp) != NULL)
7370 anon_index = svd->anon_index + seg_page(seg, addr);
7371
7372 for (eaddr = addr + len; addr < eaddr; addr += PAGESIZE) {
7373 ap = NULL;
7374 if (amp != NULL) {
7375 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
7376 anon_array_enter(amp, anon_index, &cookie);
7377 ap = anon_get_ptr(amp->ahp, anon_index++);
7378 if (ap != NULL) {
7379 swap_xlate(ap, &vp, &off);
7380 } else {
7381 vp = svd->vp;
7382 off = offset;
7383 }
7384 anon_array_exit(&cookie);
7385 ANON_LOCK_EXIT(&->a_rwlock);
7386 } else {
7387 vp = svd->vp;
7388 off = offset;
7389 }
7390 offset += PAGESIZE;
7391
7392 if (vp == NULL) /* untouched zfod page */
7393 continue;
7394
7395 if (attr) {
7396 if (vpp) {
7397 prot = VPP_PROT(vpp);
7398 vpp++;
7399 }
7400 if (prot != pageprot) {
7401 continue;
7402 }
7403 }
7404
7405 /*
7406 * See if any of these pages are locked -- if so, then we
7407 * will have to truncate an invalidate request at the first
7408 * locked one. We don't need the page_struct_lock to test
7409 * as this is only advisory; even if we acquire it someone
7410 * might race in and lock the page after we unlock and before
7411 * we do the PUTPAGE, then PUTPAGE simply does nothing.
7412 */
7413 if (flags & MS_INVALIDATE) {
7414 if ((pp = page_lookup(vp, off, SE_SHARED)) != NULL) {
7415 if (pp->p_lckcnt != 0 || pp->p_cowcnt != 0) {
7416 page_unlock(pp);
7417 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7418 return (EBUSY);
7419 }
7420 if (ap != NULL && pp->p_szc != 0 &&
7421 page_tryupgrade(pp)) {
7422 if (pp->p_lckcnt == 0 &&
7423 pp->p_cowcnt == 0) {
7424 /*
7425 * swapfs VN_DISPOSE() won't
7426 * invalidate large pages.
7427 * Attempt to demote.
7428 * XXX can't help it if it
7429 * fails. But for swapfs
7430 * pages it is no big deal.
7431 */
7432 (void) page_try_demote_pages(
7433 pp);
7434 }
7435 }
7436 page_unlock(pp);
7437 }
7438 } else if (svd->type == MAP_SHARED && amp != NULL) {
7439 /*
7440 * Avoid writing out to disk ISM's large pages
7441 * because segspt_free_pages() relies on NULL an_pvp
7442 * of anon slots of such pages.
7443 */
7444
7445 ASSERT(svd->vp == NULL);
7446 /*
7447 * swapfs uses page_lookup_nowait if not freeing or
7448 * invalidating and skips a page if
7449 * page_lookup_nowait returns NULL.
7450 */
7451 pp = page_lookup_nowait(vp, off, SE_SHARED);
7452 if (pp == NULL) {
7453 continue;
7454 }
7455 if (pp->p_szc != 0) {
7456 page_unlock(pp);
7457 continue;
7458 }
7459
7460 /*
7461 * Note ISM pages are created large so (vp, off)'s
7462 * page cannot suddenly become large after we unlock
7463 * pp.
7464 */
7465 page_unlock(pp);
7466 }
7467 /*
7468 * XXX - Should ultimately try to kluster
7469 * calls to VOP_PUTPAGE() for performance.
7470 */
7471 VN_HOLD(vp);
7472 err = VOP_PUTPAGE(vp, (offset_t)off, PAGESIZE,
7473 (bflags | (IS_SWAPFSVP(vp) ? B_PAGE_NOWAIT : 0)),
7474 svd->cred, NULL);
7475
7476 VN_RELE(vp);
7477 if (err)
7478 break;
7479 }
7480 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7481 return (err);
7482 }
7483
7484 /*
7485 * Determine if we have data corresponding to pages in the
7486 * primary storage virtual memory cache (i.e., "in core").
7487 */
7488 static size_t
segvn_incore(struct seg * seg,caddr_t addr,size_t len,char * vec)7489 segvn_incore(struct seg *seg, caddr_t addr, size_t len, char *vec)
7490 {
7491 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
7492 struct vnode *vp, *avp;
7493 u_offset_t offset, aoffset;
7494 size_t p, ep;
7495 int ret;
7496 struct vpage *vpp;
7497 page_t *pp;
7498 uint_t start;
7499 struct anon_map *amp; /* XXX - for locknest */
7500 struct anon *ap;
7501 uint_t attr;
7502 anon_sync_obj_t cookie;
7503
7504 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
7505
7506 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
7507 if (svd->amp == NULL && svd->vp == NULL) {
7508 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7509 bzero(vec, btopr(len));
7510 return (len); /* no anonymous pages created yet */
7511 }
7512
7513 p = seg_page(seg, addr);
7514 ep = seg_page(seg, addr + len);
7515 start = svd->vp ? SEG_PAGE_VNODEBACKED : 0;
7516
7517 amp = svd->amp;
7518 for (; p < ep; p++, addr += PAGESIZE) {
7519 vpp = (svd->vpage) ? &svd->vpage[p]: NULL;
7520 ret = start;
7521 ap = NULL;
7522 avp = NULL;
7523 /* Grab the vnode/offset for the anon slot */
7524 if (amp != NULL) {
7525 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
7526 anon_array_enter(amp, svd->anon_index + p, &cookie);
7527 ap = anon_get_ptr(amp->ahp, svd->anon_index + p);
7528 if (ap != NULL) {
7529 swap_xlate(ap, &avp, &aoffset);
7530 }
7531 anon_array_exit(&cookie);
7532 ANON_LOCK_EXIT(&->a_rwlock);
7533 }
7534 if ((avp != NULL) && page_exists(avp, aoffset)) {
7535 /* A page exists for the anon slot */
7536 ret |= SEG_PAGE_INCORE;
7537
7538 /*
7539 * If page is mapped and writable
7540 */
7541 attr = (uint_t)0;
7542 if ((hat_getattr(seg->s_as->a_hat, addr,
7543 &attr) != -1) && (attr & PROT_WRITE)) {
7544 ret |= SEG_PAGE_ANON;
7545 }
7546 /*
7547 * Don't get page_struct lock for lckcnt and cowcnt,
7548 * since this is purely advisory.
7549 */
7550 if ((pp = page_lookup_nowait(avp, aoffset,
7551 SE_SHARED)) != NULL) {
7552 if (pp->p_lckcnt)
7553 ret |= SEG_PAGE_SOFTLOCK;
7554 if (pp->p_cowcnt)
7555 ret |= SEG_PAGE_HASCOW;
7556 page_unlock(pp);
7557 }
7558 }
7559
7560 /* Gather vnode statistics */
7561 vp = svd->vp;
7562 offset = svd->offset + (uintptr_t)(addr - seg->s_base);
7563
7564 if (vp != NULL) {
7565 /*
7566 * Try to obtain a "shared" lock on the page
7567 * without blocking. If this fails, determine
7568 * if the page is in memory.
7569 */
7570 pp = page_lookup_nowait(vp, offset, SE_SHARED);
7571 if ((pp == NULL) && (page_exists(vp, offset))) {
7572 /* Page is incore, and is named */
7573 ret |= (SEG_PAGE_INCORE | SEG_PAGE_VNODE);
7574 }
7575 /*
7576 * Don't get page_struct lock for lckcnt and cowcnt,
7577 * since this is purely advisory.
7578 */
7579 if (pp != NULL) {
7580 ret |= (SEG_PAGE_INCORE | SEG_PAGE_VNODE);
7581 if (pp->p_lckcnt)
7582 ret |= SEG_PAGE_SOFTLOCK;
7583 if (pp->p_cowcnt)
7584 ret |= SEG_PAGE_HASCOW;
7585 page_unlock(pp);
7586 }
7587 }
7588
7589 /* Gather virtual page information */
7590 if (vpp) {
7591 if (VPP_ISPPLOCK(vpp))
7592 ret |= SEG_PAGE_LOCKED;
7593 vpp++;
7594 }
7595
7596 *vec++ = (char)ret;
7597 }
7598 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7599 return (len);
7600 }
7601
7602 /*
7603 * Statement for p_cowcnts/p_lckcnts.
7604 *
7605 * p_cowcnt is updated while mlock/munlocking MAP_PRIVATE and PROT_WRITE region
7606 * irrespective of the following factors or anything else:
7607 *
7608 * (1) anon slots are populated or not
7609 * (2) cow is broken or not
7610 * (3) refcnt on ap is 1 or greater than 1
7611 *
7612 * If it's not MAP_PRIVATE and PROT_WRITE, p_lckcnt is updated during mlock
7613 * and munlock.
7614 *
7615 *
7616 * Handling p_cowcnts/p_lckcnts during copy-on-write fault:
7617 *
7618 * if vpage has PROT_WRITE
7619 * transfer cowcnt on the oldpage -> cowcnt on the newpage
7620 * else
7621 * transfer lckcnt on the oldpage -> lckcnt on the newpage
7622 *
7623 * During copy-on-write, decrement p_cowcnt on the oldpage and increment
7624 * p_cowcnt on the newpage *if* the corresponding vpage has PROT_WRITE.
7625 *
7626 * We may also break COW if softlocking on read access in the physio case.
7627 * In this case, vpage may not have PROT_WRITE. So, we need to decrement
7628 * p_lckcnt on the oldpage and increment p_lckcnt on the newpage *if* the
7629 * vpage doesn't have PROT_WRITE.
7630 *
7631 *
7632 * Handling p_cowcnts/p_lckcnts during mprotect on mlocked region:
7633 *
7634 * If a MAP_PRIVATE region loses PROT_WRITE, we decrement p_cowcnt and
7635 * increment p_lckcnt by calling page_subclaim() which takes care of
7636 * availrmem accounting and p_lckcnt overflow.
7637 *
7638 * If a MAP_PRIVATE region gains PROT_WRITE, we decrement p_lckcnt and
7639 * increment p_cowcnt by calling page_addclaim() which takes care of
7640 * availrmem availability and p_cowcnt overflow.
7641 */
7642
7643 /*
7644 * Lock down (or unlock) pages mapped by this segment.
7645 *
7646 * XXX only creates PAGESIZE pages if anon slots are not initialized.
7647 * At fault time they will be relocated into larger pages.
7648 */
7649 static int
segvn_lockop(struct seg * seg,caddr_t addr,size_t len,int attr,int op,ulong_t * lockmap,size_t pos)7650 segvn_lockop(struct seg *seg, caddr_t addr, size_t len,
7651 int attr, int op, ulong_t *lockmap, size_t pos)
7652 {
7653 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
7654 struct vpage *vpp;
7655 struct vpage *evp;
7656 page_t *pp;
7657 u_offset_t offset;
7658 u_offset_t off;
7659 int segtype;
7660 int pageprot;
7661 int claim;
7662 struct vnode *vp;
7663 ulong_t anon_index;
7664 struct anon_map *amp;
7665 struct anon *ap;
7666 struct vattr va;
7667 anon_sync_obj_t cookie;
7668 struct kshmid *sp = NULL;
7669 struct proc *p = curproc;
7670 kproject_t *proj = NULL;
7671 int chargeproc = 1;
7672 size_t locked_bytes = 0;
7673 size_t unlocked_bytes = 0;
7674 int err = 0;
7675
7676 /*
7677 * Hold write lock on address space because may split or concatenate
7678 * segments
7679 */
7680 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
7681
7682 /*
7683 * If this is a shm, use shm's project and zone, else use
7684 * project and zone of calling process
7685 */
7686
7687 /* Determine if this segment backs a sysV shm */
7688 if (svd->amp != NULL && svd->amp->a_sp != NULL) {
7689 ASSERT(svd->type == MAP_SHARED);
7690 ASSERT(svd->tr_state == SEGVN_TR_OFF);
7691 sp = svd->amp->a_sp;
7692 proj = sp->shm_perm.ipc_proj;
7693 chargeproc = 0;
7694 }
7695
7696 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
7697 if (attr) {
7698 pageprot = attr & ~(SHARED|PRIVATE);
7699 segtype = attr & SHARED ? MAP_SHARED : MAP_PRIVATE;
7700
7701 /*
7702 * We are done if the segment types don't match
7703 * or if we have segment level protections and
7704 * they don't match.
7705 */
7706 if (svd->type != segtype) {
7707 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7708 return (0);
7709 }
7710 if (svd->pageprot == 0 && svd->prot != pageprot) {
7711 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7712 return (0);
7713 }
7714 }
7715
7716 if (op == MC_LOCK) {
7717 if (svd->tr_state == SEGVN_TR_INIT) {
7718 svd->tr_state = SEGVN_TR_OFF;
7719 } else if (svd->tr_state == SEGVN_TR_ON) {
7720 ASSERT(svd->amp != NULL);
7721 segvn_textunrepl(seg, 0);
7722 ASSERT(svd->amp == NULL &&
7723 svd->tr_state == SEGVN_TR_OFF);
7724 }
7725 }
7726
7727 /*
7728 * If we're locking, then we must create a vpage structure if
7729 * none exists. If we're unlocking, then check to see if there
7730 * is a vpage -- if not, then we could not have locked anything.
7731 */
7732
7733 if ((vpp = svd->vpage) == NULL) {
7734 if (op == MC_LOCK) {
7735 segvn_vpage(seg);
7736 if (svd->vpage == NULL) {
7737 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7738 return (ENOMEM);
7739 }
7740 } else {
7741 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7742 return (0);
7743 }
7744 }
7745
7746 /*
7747 * The anonymous data vector (i.e., previously
7748 * unreferenced mapping to swap space) can be allocated
7749 * by lazily testing for its existence.
7750 */
7751 if (op == MC_LOCK && svd->amp == NULL && svd->vp == NULL) {
7752 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
7753 svd->amp = anonmap_alloc(seg->s_size, 0, ANON_SLEEP);
7754 svd->amp->a_szc = seg->s_szc;
7755 }
7756
7757 if ((amp = svd->amp) != NULL) {
7758 anon_index = svd->anon_index + seg_page(seg, addr);
7759 }
7760
7761 offset = svd->offset + (uintptr_t)(addr - seg->s_base);
7762 evp = &svd->vpage[seg_page(seg, addr + len)];
7763
7764 if (sp != NULL)
7765 mutex_enter(&sp->shm_mlock);
7766
7767 /* determine number of unlocked bytes in range for lock operation */
7768 if (op == MC_LOCK) {
7769
7770 if (sp == NULL) {
7771 for (vpp = &svd->vpage[seg_page(seg, addr)]; vpp < evp;
7772 vpp++) {
7773 if (!VPP_ISPPLOCK(vpp))
7774 unlocked_bytes += PAGESIZE;
7775 }
7776 } else {
7777 ulong_t i_idx, i_edx;
7778 anon_sync_obj_t i_cookie;
7779 struct anon *i_ap;
7780 struct vnode *i_vp;
7781 u_offset_t i_off;
7782
7783 /* Only count sysV pages once for locked memory */
7784 i_edx = svd->anon_index + seg_page(seg, addr + len);
7785 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
7786 for (i_idx = anon_index; i_idx < i_edx; i_idx++) {
7787 anon_array_enter(amp, i_idx, &i_cookie);
7788 i_ap = anon_get_ptr(amp->ahp, i_idx);
7789 if (i_ap == NULL) {
7790 unlocked_bytes += PAGESIZE;
7791 anon_array_exit(&i_cookie);
7792 continue;
7793 }
7794 swap_xlate(i_ap, &i_vp, &i_off);
7795 anon_array_exit(&i_cookie);
7796 pp = page_lookup(i_vp, i_off, SE_SHARED);
7797 if (pp == NULL) {
7798 unlocked_bytes += PAGESIZE;
7799 continue;
7800 } else if (pp->p_lckcnt == 0)
7801 unlocked_bytes += PAGESIZE;
7802 page_unlock(pp);
7803 }
7804 ANON_LOCK_EXIT(&->a_rwlock);
7805 }
7806
7807 mutex_enter(&p->p_lock);
7808 err = rctl_incr_locked_mem(p, proj, unlocked_bytes,
7809 chargeproc);
7810 mutex_exit(&p->p_lock);
7811
7812 if (err) {
7813 if (sp != NULL)
7814 mutex_exit(&sp->shm_mlock);
7815 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
7816 return (err);
7817 }
7818 }
7819 /*
7820 * Loop over all pages in the range. Process if we're locking and
7821 * page has not already been locked in this mapping; or if we're
7822 * unlocking and the page has been locked.
7823 */
7824 for (vpp = &svd->vpage[seg_page(seg, addr)]; vpp < evp;
7825 vpp++, pos++, addr += PAGESIZE, offset += PAGESIZE, anon_index++) {
7826 if ((attr == 0 || VPP_PROT(vpp) == pageprot) &&
7827 ((op == MC_LOCK && !VPP_ISPPLOCK(vpp)) ||
7828 (op == MC_UNLOCK && VPP_ISPPLOCK(vpp)))) {
7829
7830 if (amp != NULL)
7831 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
7832 /*
7833 * If this isn't a MAP_NORESERVE segment and
7834 * we're locking, allocate anon slots if they
7835 * don't exist. The page is brought in later on.
7836 */
7837 if (op == MC_LOCK && svd->vp == NULL &&
7838 ((svd->flags & MAP_NORESERVE) == 0) &&
7839 amp != NULL &&
7840 ((ap = anon_get_ptr(amp->ahp, anon_index))
7841 == NULL)) {
7842 anon_array_enter(amp, anon_index, &cookie);
7843
7844 if ((ap = anon_get_ptr(amp->ahp,
7845 anon_index)) == NULL) {
7846 pp = anon_zero(seg, addr, &ap,
7847 svd->cred);
7848 if (pp == NULL) {
7849 anon_array_exit(&cookie);
7850 ANON_LOCK_EXIT(&->a_rwlock);
7851 err = ENOMEM;
7852 goto out;
7853 }
7854 ASSERT(anon_get_ptr(amp->ahp,
7855 anon_index) == NULL);
7856 (void) anon_set_ptr(amp->ahp,
7857 anon_index, ap, ANON_SLEEP);
7858 page_unlock(pp);
7859 }
7860 anon_array_exit(&cookie);
7861 }
7862
7863 /*
7864 * Get name for page, accounting for
7865 * existence of private copy.
7866 */
7867 ap = NULL;
7868 if (amp != NULL) {
7869 anon_array_enter(amp, anon_index, &cookie);
7870 ap = anon_get_ptr(amp->ahp, anon_index);
7871 if (ap != NULL) {
7872 swap_xlate(ap, &vp, &off);
7873 } else {
7874 if (svd->vp == NULL &&
7875 (svd->flags & MAP_NORESERVE)) {
7876 anon_array_exit(&cookie);
7877 ANON_LOCK_EXIT(&->a_rwlock);
7878 continue;
7879 }
7880 vp = svd->vp;
7881 off = offset;
7882 }
7883 if (op != MC_LOCK || ap == NULL) {
7884 anon_array_exit(&cookie);
7885 ANON_LOCK_EXIT(&->a_rwlock);
7886 }
7887 } else {
7888 vp = svd->vp;
7889 off = offset;
7890 }
7891
7892 /*
7893 * Get page frame. It's ok if the page is
7894 * not available when we're unlocking, as this
7895 * may simply mean that a page we locked got
7896 * truncated out of existence after we locked it.
7897 *
7898 * Invoke VOP_GETPAGE() to obtain the page struct
7899 * since we may need to read it from disk if its
7900 * been paged out.
7901 */
7902 if (op != MC_LOCK)
7903 pp = page_lookup(vp, off, SE_SHARED);
7904 else {
7905 page_t *pl[1 + 1];
7906 int error;
7907
7908 ASSERT(vp != NULL);
7909
7910 error = VOP_GETPAGE(vp, (offset_t)off, PAGESIZE,
7911 (uint_t *)NULL, pl, PAGESIZE, seg, addr,
7912 S_OTHER, svd->cred, NULL);
7913
7914 if (error && ap != NULL) {
7915 anon_array_exit(&cookie);
7916 ANON_LOCK_EXIT(&->a_rwlock);
7917 }
7918
7919 /*
7920 * If the error is EDEADLK then we must bounce
7921 * up and drop all vm subsystem locks and then
7922 * retry the operation later
7923 * This behavior is a temporary measure because
7924 * ufs/sds logging is badly designed and will
7925 * deadlock if we don't allow this bounce to
7926 * happen. The real solution is to re-design
7927 * the logging code to work properly. See bug
7928 * 4125102 for details of the problem.
7929 */
7930 if (error == EDEADLK) {
7931 err = error;
7932 goto out;
7933 }
7934 /*
7935 * Quit if we fail to fault in the page. Treat
7936 * the failure as an error, unless the addr
7937 * is mapped beyond the end of a file.
7938 */
7939 if (error && svd->vp) {
7940 va.va_mask = AT_SIZE;
7941 if (VOP_GETATTR(svd->vp, &va, 0,
7942 svd->cred, NULL) != 0) {
7943 err = EIO;
7944 goto out;
7945 }
7946 if (btopr(va.va_size) >=
7947 btopr(off + 1)) {
7948 err = EIO;
7949 goto out;
7950 }
7951 goto out;
7952
7953 } else if (error) {
7954 err = EIO;
7955 goto out;
7956 }
7957 pp = pl[0];
7958 ASSERT(pp != NULL);
7959 }
7960
7961 /*
7962 * See Statement at the beginning of this routine.
7963 *
7964 * claim is always set if MAP_PRIVATE and PROT_WRITE
7965 * irrespective of following factors:
7966 *
7967 * (1) anon slots are populated or not
7968 * (2) cow is broken or not
7969 * (3) refcnt on ap is 1 or greater than 1
7970 *
7971 * See 4140683 for details
7972 */
7973 claim = ((VPP_PROT(vpp) & PROT_WRITE) &&
7974 (svd->type == MAP_PRIVATE));
7975
7976 /*
7977 * Perform page-level operation appropriate to
7978 * operation. If locking, undo the SOFTLOCK
7979 * performed to bring the page into memory
7980 * after setting the lock. If unlocking,
7981 * and no page was found, account for the claim
7982 * separately.
7983 */
7984 if (op == MC_LOCK) {
7985 int ret = 1; /* Assume success */
7986
7987 ASSERT(!VPP_ISPPLOCK(vpp));
7988
7989 ret = page_pp_lock(pp, claim, 0);
7990 if (ap != NULL) {
7991 if (ap->an_pvp != NULL) {
7992 anon_swap_free(ap, pp);
7993 }
7994 anon_array_exit(&cookie);
7995 ANON_LOCK_EXIT(&->a_rwlock);
7996 }
7997 if (ret == 0) {
7998 /* locking page failed */
7999 page_unlock(pp);
8000 err = EAGAIN;
8001 goto out;
8002 }
8003 VPP_SETPPLOCK(vpp);
8004 if (sp != NULL) {
8005 if (pp->p_lckcnt == 1)
8006 locked_bytes += PAGESIZE;
8007 } else
8008 locked_bytes += PAGESIZE;
8009
8010 if (lockmap != (ulong_t *)NULL)
8011 BT_SET(lockmap, pos);
8012
8013 page_unlock(pp);
8014 } else {
8015 ASSERT(VPP_ISPPLOCK(vpp));
8016 if (pp != NULL) {
8017 /* sysV pages should be locked */
8018 ASSERT(sp == NULL || pp->p_lckcnt > 0);
8019 page_pp_unlock(pp, claim, 0);
8020 if (sp != NULL) {
8021 if (pp->p_lckcnt == 0)
8022 unlocked_bytes
8023 += PAGESIZE;
8024 } else
8025 unlocked_bytes += PAGESIZE;
8026 page_unlock(pp);
8027 } else {
8028 ASSERT(sp == NULL);
8029 unlocked_bytes += PAGESIZE;
8030 }
8031 VPP_CLRPPLOCK(vpp);
8032 }
8033 }
8034 }
8035 out:
8036 if (op == MC_LOCK) {
8037 /* Credit back bytes that did not get locked */
8038 if ((unlocked_bytes - locked_bytes) > 0) {
8039 if (proj == NULL)
8040 mutex_enter(&p->p_lock);
8041 rctl_decr_locked_mem(p, proj,
8042 (unlocked_bytes - locked_bytes), chargeproc);
8043 if (proj == NULL)
8044 mutex_exit(&p->p_lock);
8045 }
8046
8047 } else {
8048 /* Account bytes that were unlocked */
8049 if (unlocked_bytes > 0) {
8050 if (proj == NULL)
8051 mutex_enter(&p->p_lock);
8052 rctl_decr_locked_mem(p, proj, unlocked_bytes,
8053 chargeproc);
8054 if (proj == NULL)
8055 mutex_exit(&p->p_lock);
8056 }
8057 }
8058 if (sp != NULL)
8059 mutex_exit(&sp->shm_mlock);
8060 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8061
8062 return (err);
8063 }
8064
8065 /*
8066 * Set advice from user for specified pages
8067 * There are 10 types of advice:
8068 * MADV_NORMAL - Normal (default) behavior (whatever that is)
8069 * MADV_RANDOM - Random page references
8070 * do not allow readahead or 'klustering'
8071 * MADV_SEQUENTIAL - Sequential page references
8072 * Pages previous to the one currently being
8073 * accessed (determined by fault) are 'not needed'
8074 * and are freed immediately
8075 * MADV_WILLNEED - Pages are likely to be used (fault ahead in mctl)
8076 * MADV_DONTNEED - Pages are not needed (synced out in mctl)
8077 * MADV_FREE - Contents can be discarded
8078 * MADV_ACCESS_DEFAULT- Default access
8079 * MADV_ACCESS_LWP - Next LWP will access heavily
8080 * MADV_ACCESS_MANY- Many LWPs or processes will access heavily
8081 * MADV_PURGE - Contents will be immediately discarded
8082 */
8083 static int
segvn_advise(struct seg * seg,caddr_t addr,size_t len,uint_t behav)8084 segvn_advise(struct seg *seg, caddr_t addr, size_t len, uint_t behav)
8085 {
8086 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
8087 size_t page;
8088 int err = 0;
8089 int already_set;
8090 struct anon_map *amp;
8091 ulong_t anon_index;
8092 struct seg *next;
8093 lgrp_mem_policy_t policy;
8094 struct seg *prev;
8095 struct vnode *vp;
8096
8097 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
8098
8099 /*
8100 * In case of MADV_FREE/MADV_PURGE, we won't be modifying any segment
8101 * private data structures; so, we only need to grab READER's lock
8102 */
8103 if (behav != MADV_FREE && behav != MADV_PURGE) {
8104 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
8105 if (svd->tr_state != SEGVN_TR_OFF) {
8106 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8107 return (0);
8108 }
8109 } else {
8110 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
8111 }
8112
8113 /*
8114 * Large pages are assumed to be only turned on when accesses to the
8115 * segment's address range have spatial and temporal locality. That
8116 * justifies ignoring MADV_SEQUENTIAL for large page segments.
8117 * Also, ignore advice affecting lgroup memory allocation
8118 * if don't need to do lgroup optimizations on this system
8119 */
8120
8121 if ((behav == MADV_SEQUENTIAL &&
8122 (seg->s_szc != 0 || HAT_IS_REGION_COOKIE_VALID(svd->rcookie))) ||
8123 (!lgrp_optimizations() && (behav == MADV_ACCESS_DEFAULT ||
8124 behav == MADV_ACCESS_LWP || behav == MADV_ACCESS_MANY))) {
8125 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8126 return (0);
8127 }
8128
8129 if (behav == MADV_SEQUENTIAL || behav == MADV_ACCESS_DEFAULT ||
8130 behav == MADV_ACCESS_LWP || behav == MADV_ACCESS_MANY) {
8131 /*
8132 * Since we are going to unload hat mappings
8133 * we first have to flush the cache. Otherwise
8134 * this might lead to system panic if another
8135 * thread is doing physio on the range whose
8136 * mappings are unloaded by madvise(3C).
8137 */
8138 if (svd->softlockcnt > 0) {
8139 /*
8140 * If this is shared segment non 0 softlockcnt
8141 * means locked pages are still in use.
8142 */
8143 if (svd->type == MAP_SHARED) {
8144 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8145 return (EAGAIN);
8146 }
8147 /*
8148 * Since we do have the segvn writers lock
8149 * nobody can fill the cache with entries
8150 * belonging to this seg during the purge.
8151 * The flush either succeeds or we still
8152 * have pending I/Os. In the later case,
8153 * madvise(3C) fails.
8154 */
8155 segvn_purge(seg);
8156 if (svd->softlockcnt > 0) {
8157 /*
8158 * Since madvise(3C) is advisory and
8159 * it's not part of UNIX98, madvise(3C)
8160 * failure here doesn't cause any hardship.
8161 * Note that we don't block in "as" layer.
8162 */
8163 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8164 return (EAGAIN);
8165 }
8166 } else if (svd->type == MAP_SHARED && svd->amp != NULL &&
8167 svd->amp->a_softlockcnt > 0) {
8168 /*
8169 * Try to purge this amp's entries from pcache. It
8170 * will succeed only if other segments that share the
8171 * amp have no outstanding softlock's.
8172 */
8173 segvn_purge(seg);
8174 }
8175 }
8176
8177 amp = svd->amp;
8178 vp = svd->vp;
8179 if (behav == MADV_FREE || behav == MADV_PURGE) {
8180 pgcnt_t purged;
8181
8182 if (behav == MADV_FREE && (vp != NULL || amp == NULL)) {
8183 /*
8184 * MADV_FREE is not supported for segments with an
8185 * underlying object; if anonmap is NULL, anon slots
8186 * are not yet populated and there is nothing for us
8187 * to do. As MADV_FREE is advisory, we don't return an
8188 * error in either case.
8189 */
8190 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8191 return (0);
8192 }
8193
8194 if (amp == NULL) {
8195 /*
8196 * If we're here with a NULL anonmap, it's because we
8197 * are doing a MADV_PURGE. We have nothing to do, but
8198 * because MADV_PURGE isn't merely advisory, we return
8199 * an error in this case.
8200 */
8201 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8202 return (EBUSY);
8203 }
8204
8205 segvn_purge(seg);
8206
8207 page = seg_page(seg, addr);
8208 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
8209 err = anon_disclaim(amp,
8210 svd->anon_index + page, len, behav, &purged);
8211
8212 if (purged != 0 && (svd->flags & MAP_NORESERVE)) {
8213 /*
8214 * If we purged pages on a MAP_NORESERVE mapping, we
8215 * need to be sure to now unreserve our reserved swap.
8216 * (We use the atomic operations to manipulate our
8217 * segment and address space counters because we only
8218 * have the corresponding locks held as reader, not
8219 * writer.)
8220 */
8221 ssize_t bytes = ptob(purged);
8222
8223 anon_unresv_zone(bytes, seg->s_as->a_proc->p_zone);
8224 atomic_add_long(&svd->swresv, -bytes);
8225 atomic_add_long(&seg->s_as->a_resvsize, -bytes);
8226 }
8227
8228 ANON_LOCK_EXIT(&->a_rwlock);
8229 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8230
8231 /*
8232 * MADV_PURGE and MADV_FREE differ in their return semantics:
8233 * because MADV_PURGE is designed to be bug-for-bug compatible
8234 * with its clumsy Linux forebear, it will fail where MADV_FREE
8235 * does not.
8236 */
8237 return (behav == MADV_PURGE ? err : 0);
8238 }
8239
8240 /*
8241 * If advice is to be applied to entire segment,
8242 * use advice field in seg_data structure
8243 * otherwise use appropriate vpage entry.
8244 */
8245 if ((addr == seg->s_base) && (len == seg->s_size)) {
8246 switch (behav) {
8247 case MADV_ACCESS_LWP:
8248 case MADV_ACCESS_MANY:
8249 case MADV_ACCESS_DEFAULT:
8250 /*
8251 * Set memory allocation policy for this segment
8252 */
8253 policy = lgrp_madv_to_policy(behav, len, svd->type);
8254 if (svd->type == MAP_SHARED)
8255 already_set = lgrp_shm_policy_set(policy, amp,
8256 svd->anon_index, vp, svd->offset, len);
8257 else {
8258 /*
8259 * For private memory, need writers lock on
8260 * address space because the segment may be
8261 * split or concatenated when changing policy
8262 */
8263 if (AS_READ_HELD(seg->s_as)) {
8264 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8265 return (IE_RETRY);
8266 }
8267
8268 already_set = lgrp_privm_policy_set(policy,
8269 &svd->policy_info, len);
8270 }
8271
8272 /*
8273 * If policy set already and it shouldn't be reapplied,
8274 * don't do anything.
8275 */
8276 if (already_set &&
8277 !LGRP_MEM_POLICY_REAPPLICABLE(policy))
8278 break;
8279
8280 /*
8281 * Mark any existing pages in given range for
8282 * migration
8283 */
8284 page_mark_migrate(seg, addr, len, amp, svd->anon_index,
8285 vp, svd->offset, 1);
8286
8287 /*
8288 * If same policy set already or this is a shared
8289 * memory segment, don't need to try to concatenate
8290 * segment with adjacent ones.
8291 */
8292 if (already_set || svd->type == MAP_SHARED)
8293 break;
8294
8295 /*
8296 * Try to concatenate this segment with previous
8297 * one and next one, since we changed policy for
8298 * this one and it may be compatible with adjacent
8299 * ones now.
8300 */
8301 prev = AS_SEGPREV(seg->s_as, seg);
8302 next = AS_SEGNEXT(seg->s_as, seg);
8303
8304 if (next && next->s_ops == &segvn_ops &&
8305 addr + len == next->s_base)
8306 (void) segvn_concat(seg, next, 1);
8307
8308 if (prev && prev->s_ops == &segvn_ops &&
8309 addr == prev->s_base + prev->s_size) {
8310 /*
8311 * Drop lock for private data of current
8312 * segment before concatenating (deleting) it
8313 * and return IE_REATTACH to tell as_ctl() that
8314 * current segment has changed
8315 */
8316 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8317 if (!segvn_concat(prev, seg, 1))
8318 err = IE_REATTACH;
8319
8320 return (err);
8321 }
8322 break;
8323
8324 case MADV_SEQUENTIAL:
8325 /*
8326 * unloading mapping guarantees
8327 * detection in segvn_fault
8328 */
8329 ASSERT(seg->s_szc == 0);
8330 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
8331 hat_unload(seg->s_as->a_hat, addr, len,
8332 HAT_UNLOAD);
8333 /* FALLTHROUGH */
8334 case MADV_NORMAL:
8335 case MADV_RANDOM:
8336 svd->advice = (uchar_t)behav;
8337 svd->pageadvice = 0;
8338 break;
8339 case MADV_WILLNEED: /* handled in memcntl */
8340 case MADV_DONTNEED: /* handled in memcntl */
8341 case MADV_FREE: /* handled above */
8342 case MADV_PURGE: /* handled above */
8343 break;
8344 default:
8345 err = EINVAL;
8346 }
8347 } else {
8348 caddr_t eaddr;
8349 struct seg *new_seg;
8350 struct segvn_data *new_svd;
8351 u_offset_t off;
8352 caddr_t oldeaddr;
8353
8354 page = seg_page(seg, addr);
8355
8356 segvn_vpage(seg);
8357 if (svd->vpage == NULL) {
8358 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8359 return (ENOMEM);
8360 }
8361
8362 switch (behav) {
8363 struct vpage *bvpp, *evpp;
8364
8365 case MADV_ACCESS_LWP:
8366 case MADV_ACCESS_MANY:
8367 case MADV_ACCESS_DEFAULT:
8368 /*
8369 * Set memory allocation policy for portion of this
8370 * segment
8371 */
8372
8373 /*
8374 * Align address and length of advice to page
8375 * boundaries for large pages
8376 */
8377 if (seg->s_szc != 0) {
8378 size_t pgsz;
8379
8380 pgsz = page_get_pagesize(seg->s_szc);
8381 addr = (caddr_t)P2ALIGN((uintptr_t)addr, pgsz);
8382 len = P2ROUNDUP(len, pgsz);
8383 }
8384
8385 /*
8386 * Check to see whether policy is set already
8387 */
8388 policy = lgrp_madv_to_policy(behav, len, svd->type);
8389
8390 anon_index = svd->anon_index + page;
8391 off = svd->offset + (uintptr_t)(addr - seg->s_base);
8392
8393 if (svd->type == MAP_SHARED)
8394 already_set = lgrp_shm_policy_set(policy, amp,
8395 anon_index, vp, off, len);
8396 else
8397 already_set =
8398 (policy == svd->policy_info.mem_policy);
8399
8400 /*
8401 * If policy set already and it shouldn't be reapplied,
8402 * don't do anything.
8403 */
8404 if (already_set &&
8405 !LGRP_MEM_POLICY_REAPPLICABLE(policy))
8406 break;
8407
8408 /*
8409 * For private memory, need writers lock on
8410 * address space because the segment may be
8411 * split or concatenated when changing policy
8412 */
8413 if (svd->type == MAP_PRIVATE &&
8414 AS_READ_HELD(seg->s_as)) {
8415 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8416 return (IE_RETRY);
8417 }
8418
8419 /*
8420 * Mark any existing pages in given range for
8421 * migration
8422 */
8423 page_mark_migrate(seg, addr, len, amp, svd->anon_index,
8424 vp, svd->offset, 1);
8425
8426 /*
8427 * Don't need to try to split or concatenate
8428 * segments, since policy is same or this is a shared
8429 * memory segment
8430 */
8431 if (already_set || svd->type == MAP_SHARED)
8432 break;
8433
8434 if (HAT_IS_REGION_COOKIE_VALID(svd->rcookie)) {
8435 ASSERT(svd->amp == NULL);
8436 ASSERT(svd->tr_state == SEGVN_TR_OFF);
8437 ASSERT(svd->softlockcnt == 0);
8438 hat_leave_region(seg->s_as->a_hat, svd->rcookie,
8439 HAT_REGION_TEXT);
8440 svd->rcookie = HAT_INVALID_REGION_COOKIE;
8441 }
8442
8443 /*
8444 * Split off new segment if advice only applies to a
8445 * portion of existing segment starting in middle
8446 */
8447 new_seg = NULL;
8448 eaddr = addr + len;
8449 oldeaddr = seg->s_base + seg->s_size;
8450 if (addr > seg->s_base) {
8451 /*
8452 * Must flush I/O page cache
8453 * before splitting segment
8454 */
8455 if (svd->softlockcnt > 0)
8456 segvn_purge(seg);
8457
8458 /*
8459 * Split segment and return IE_REATTACH to tell
8460 * as_ctl() that current segment changed
8461 */
8462 new_seg = segvn_split_seg(seg, addr);
8463 new_svd = (struct segvn_data *)new_seg->s_data;
8464 err = IE_REATTACH;
8465
8466 /*
8467 * If new segment ends where old one
8468 * did, try to concatenate the new
8469 * segment with next one.
8470 */
8471 if (eaddr == oldeaddr) {
8472 /*
8473 * Set policy for new segment
8474 */
8475 (void) lgrp_privm_policy_set(policy,
8476 &new_svd->policy_info,
8477 new_seg->s_size);
8478
8479 next = AS_SEGNEXT(new_seg->s_as,
8480 new_seg);
8481
8482 if (next &&
8483 next->s_ops == &segvn_ops &&
8484 eaddr == next->s_base)
8485 (void) segvn_concat(new_seg,
8486 next, 1);
8487 }
8488 }
8489
8490 /*
8491 * Split off end of existing segment if advice only
8492 * applies to a portion of segment ending before
8493 * end of the existing segment
8494 */
8495 if (eaddr < oldeaddr) {
8496 /*
8497 * Must flush I/O page cache
8498 * before splitting segment
8499 */
8500 if (svd->softlockcnt > 0)
8501 segvn_purge(seg);
8502
8503 /*
8504 * If beginning of old segment was already
8505 * split off, use new segment to split end off
8506 * from.
8507 */
8508 if (new_seg != NULL && new_seg != seg) {
8509 /*
8510 * Split segment
8511 */
8512 (void) segvn_split_seg(new_seg, eaddr);
8513
8514 /*
8515 * Set policy for new segment
8516 */
8517 (void) lgrp_privm_policy_set(policy,
8518 &new_svd->policy_info,
8519 new_seg->s_size);
8520 } else {
8521 /*
8522 * Split segment and return IE_REATTACH
8523 * to tell as_ctl() that current
8524 * segment changed
8525 */
8526 (void) segvn_split_seg(seg, eaddr);
8527 err = IE_REATTACH;
8528
8529 (void) lgrp_privm_policy_set(policy,
8530 &svd->policy_info, seg->s_size);
8531
8532 /*
8533 * If new segment starts where old one
8534 * did, try to concatenate it with
8535 * previous segment.
8536 */
8537 if (addr == seg->s_base) {
8538 prev = AS_SEGPREV(seg->s_as,
8539 seg);
8540
8541 /*
8542 * Drop lock for private data
8543 * of current segment before
8544 * concatenating (deleting) it
8545 */
8546 if (prev &&
8547 prev->s_ops ==
8548 &segvn_ops &&
8549 addr == prev->s_base +
8550 prev->s_size) {
8551 SEGVN_LOCK_EXIT(
8552 seg->s_as,
8553 &svd->lock);
8554 (void) segvn_concat(
8555 prev, seg, 1);
8556 return (err);
8557 }
8558 }
8559 }
8560 }
8561 break;
8562 case MADV_SEQUENTIAL:
8563 ASSERT(seg->s_szc == 0);
8564 ASSERT(svd->rcookie == HAT_INVALID_REGION_COOKIE);
8565 hat_unload(seg->s_as->a_hat, addr, len, HAT_UNLOAD);
8566 /* FALLTHROUGH */
8567 case MADV_NORMAL:
8568 case MADV_RANDOM:
8569 bvpp = &svd->vpage[page];
8570 evpp = &svd->vpage[page + (len >> PAGESHIFT)];
8571 for (; bvpp < evpp; bvpp++)
8572 VPP_SETADVICE(bvpp, behav);
8573 svd->advice = MADV_NORMAL;
8574 break;
8575 case MADV_WILLNEED: /* handled in memcntl */
8576 case MADV_DONTNEED: /* handled in memcntl */
8577 case MADV_FREE: /* handled above */
8578 case MADV_PURGE: /* handled above */
8579 break;
8580 default:
8581 err = EINVAL;
8582 }
8583 }
8584 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8585 return (err);
8586 }
8587
8588 /*
8589 * There is one kind of inheritance that can be specified for pages:
8590 *
8591 * SEGP_INH_ZERO - Pages should be zeroed in the child
8592 */
8593 static int
segvn_inherit(struct seg * seg,caddr_t addr,size_t len,uint_t behav)8594 segvn_inherit(struct seg *seg, caddr_t addr, size_t len, uint_t behav)
8595 {
8596 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
8597 struct vpage *bvpp, *evpp;
8598 size_t page;
8599 int ret = 0;
8600
8601 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
8602
8603 /* Can't support something we don't know about */
8604 if (behav != SEGP_INH_ZERO)
8605 return (ENOTSUP);
8606
8607 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_WRITER);
8608
8609 /*
8610 * This must be a straightforward anonymous segment that is mapped
8611 * privately and is not backed by a vnode.
8612 */
8613 if (svd->tr_state != SEGVN_TR_OFF ||
8614 svd->type != MAP_PRIVATE ||
8615 svd->vp != NULL) {
8616 ret = EINVAL;
8617 goto out;
8618 }
8619
8620 /*
8621 * If the entire segment has been marked as inherit zero, then no reason
8622 * to do anything else.
8623 */
8624 if (svd->svn_inz == SEGVN_INZ_ALL) {
8625 ret = 0;
8626 goto out;
8627 }
8628
8629 /*
8630 * If this applies to the entire segment, simply mark it and we're done.
8631 */
8632 if ((addr == seg->s_base) && (len == seg->s_size)) {
8633 svd->svn_inz = SEGVN_INZ_ALL;
8634 ret = 0;
8635 goto out;
8636 }
8637
8638 /*
8639 * We've been asked to mark a subset of this segment as inherit zero,
8640 * therefore we need to mainpulate its vpages.
8641 */
8642 if (svd->vpage == NULL) {
8643 segvn_vpage(seg);
8644 if (svd->vpage == NULL) {
8645 ret = ENOMEM;
8646 goto out;
8647 }
8648 }
8649
8650 svd->svn_inz = SEGVN_INZ_VPP;
8651 page = seg_page(seg, addr);
8652 bvpp = &svd->vpage[page];
8653 evpp = &svd->vpage[page + (len >> PAGESHIFT)];
8654 for (; bvpp < evpp; bvpp++)
8655 VPP_SETINHZERO(bvpp);
8656 ret = 0;
8657
8658 out:
8659 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
8660 return (ret);
8661 }
8662
8663 /*
8664 * Create a vpage structure for this seg.
8665 */
8666 static void
segvn_vpage(struct seg * seg)8667 segvn_vpage(struct seg *seg)
8668 {
8669 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
8670 struct vpage *vp, *evp;
8671 static pgcnt_t page_limit = 0;
8672
8673 ASSERT(SEGVN_WRITE_HELD(seg->s_as, &svd->lock));
8674
8675 /*
8676 * If no vpage structure exists, allocate one. Copy the protections
8677 * and the advice from the segment itself to the individual pages.
8678 */
8679 if (svd->vpage == NULL) {
8680 /*
8681 * Start by calculating the number of pages we must allocate to
8682 * track the per-page vpage structs needs for this entire
8683 * segment. If we know now that it will require more than our
8684 * heuristic for the maximum amount of kmem we can consume then
8685 * fail. We do this here, instead of trying to detect this deep
8686 * in page_resv and propagating the error up, since the entire
8687 * memory allocation stack is not amenable to passing this
8688 * back. Instead, it wants to keep trying.
8689 *
8690 * As a heuristic we set a page limit of 5/8s of total_pages
8691 * for this allocation. We use shifts so that no floating
8692 * point conversion takes place and only need to do the
8693 * calculation once.
8694 */
8695 ulong_t mem_needed = seg_pages(seg) * sizeof (struct vpage);
8696 pgcnt_t npages = mem_needed >> PAGESHIFT;
8697
8698 if (page_limit == 0)
8699 page_limit = (total_pages >> 1) + (total_pages >> 3);
8700
8701 if (npages > page_limit)
8702 return;
8703
8704 svd->pageadvice = 1;
8705 svd->vpage = kmem_zalloc(mem_needed, KM_SLEEP);
8706 evp = &svd->vpage[seg_page(seg, seg->s_base + seg->s_size)];
8707 for (vp = svd->vpage; vp < evp; vp++) {
8708 VPP_SETPROT(vp, svd->prot);
8709 VPP_SETADVICE(vp, svd->advice);
8710 }
8711 }
8712 }
8713
8714 /*
8715 * Dump the pages belonging to this segvn segment.
8716 */
8717 static void
segvn_dump(struct seg * seg)8718 segvn_dump(struct seg *seg)
8719 {
8720 struct segvn_data *svd;
8721 page_t *pp;
8722 struct anon_map *amp;
8723 ulong_t anon_index;
8724 struct vnode *vp;
8725 u_offset_t off, offset;
8726 pfn_t pfn;
8727 pgcnt_t page, npages;
8728 caddr_t addr;
8729
8730 npages = seg_pages(seg);
8731 svd = (struct segvn_data *)seg->s_data;
8732 vp = svd->vp;
8733 off = offset = svd->offset;
8734 addr = seg->s_base;
8735
8736 if ((amp = svd->amp) != NULL) {
8737 anon_index = svd->anon_index;
8738 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
8739 }
8740
8741 for (page = 0; page < npages; page++, offset += PAGESIZE) {
8742 struct anon *ap;
8743 int we_own_it = 0;
8744
8745 if (amp && (ap = anon_get_ptr(svd->amp->ahp, anon_index++))) {
8746 swap_xlate_nopanic(ap, &vp, &off);
8747 } else {
8748 vp = svd->vp;
8749 off = offset;
8750 }
8751
8752 /*
8753 * If pp == NULL, the page either does not exist
8754 * or is exclusively locked. So determine if it
8755 * exists before searching for it.
8756 */
8757
8758 if ((pp = page_lookup_nowait(vp, off, SE_SHARED)))
8759 we_own_it = 1;
8760 else
8761 pp = page_exists(vp, off);
8762
8763 if (pp) {
8764 pfn = page_pptonum(pp);
8765 dump_addpage(seg->s_as, addr, pfn);
8766 if (we_own_it)
8767 page_unlock(pp);
8768 }
8769 addr += PAGESIZE;
8770 dump_timeleft = dump_timeout;
8771 }
8772
8773 if (amp != NULL)
8774 ANON_LOCK_EXIT(&->a_rwlock);
8775 }
8776
8777 #ifdef DEBUG
8778 static uint32_t segvn_pglock_mtbf = 0;
8779 #endif
8780
8781 #define PCACHE_SHWLIST ((page_t *)-2)
8782 #define NOPCACHE_SHWLIST ((page_t *)-1)
8783
8784 /*
8785 * Lock/Unlock anon pages over a given range. Return shadow list. This routine
8786 * uses global segment pcache to cache shadow lists (i.e. pp arrays) of pages
8787 * to avoid the overhead of per page locking, unlocking for subsequent IOs to
8788 * the same parts of the segment. Currently shadow list creation is only
8789 * supported for pure anon segments. MAP_PRIVATE segment pcache entries are
8790 * tagged with segment pointer, starting virtual address and length. This
8791 * approach for MAP_SHARED segments may add many pcache entries for the same
8792 * set of pages and lead to long hash chains that decrease pcache lookup
8793 * performance. To avoid this issue for shared segments shared anon map and
8794 * starting anon index are used for pcache entry tagging. This allows all
8795 * segments to share pcache entries for the same anon range and reduces pcache
8796 * chain's length as well as memory overhead from duplicate shadow lists and
8797 * pcache entries.
8798 *
8799 * softlockcnt field in segvn_data structure counts the number of F_SOFTLOCK'd
8800 * pages via segvn_fault() and pagelock'd pages via this routine. But pagelock
8801 * part of softlockcnt accounting is done differently for private and shared
8802 * segments. In private segment case softlock is only incremented when a new
8803 * shadow list is created but not when an existing one is found via
8804 * seg_plookup(). pcache entries have reference count incremented/decremented
8805 * by each seg_plookup()/seg_pinactive() operation. Only entries that have 0
8806 * reference count can be purged (and purging is needed before segment can be
8807 * freed). When a private segment pcache entry is purged segvn_reclaim() will
8808 * decrement softlockcnt. Since in private segment case each of its pcache
8809 * entries only belongs to this segment we can expect that when
8810 * segvn_pagelock(L_PAGEUNLOCK) was called for all outstanding IOs in this
8811 * segment purge will succeed and softlockcnt will drop to 0. In shared
8812 * segment case reference count in pcache entry counts active locks from many
8813 * different segments so we can't expect segment purging to succeed even when
8814 * segvn_pagelock(L_PAGEUNLOCK) was called for all outstanding IOs in this
8815 * segment. To be able to determine when there're no pending pagelocks in
8816 * shared segment case we don't rely on purging to make softlockcnt drop to 0
8817 * but instead softlockcnt is incremented and decremented for every
8818 * segvn_pagelock(L_PAGELOCK/L_PAGEUNLOCK) call regardless if a new shadow
8819 * list was created or an existing one was found. When softlockcnt drops to 0
8820 * this segment no longer has any claims for pcached shadow lists and the
8821 * segment can be freed even if there're still active pcache entries
8822 * shared by this segment anon map. Shared segment pcache entries belong to
8823 * anon map and are typically removed when anon map is freed after all
8824 * processes destroy the segments that use this anon map.
8825 */
8826 static int
segvn_pagelock(struct seg * seg,caddr_t addr,size_t len,struct page *** ppp,enum lock_type type,enum seg_rw rw)8827 segvn_pagelock(struct seg *seg, caddr_t addr, size_t len, struct page ***ppp,
8828 enum lock_type type, enum seg_rw rw)
8829 {
8830 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
8831 size_t np;
8832 pgcnt_t adjustpages;
8833 pgcnt_t npages;
8834 ulong_t anon_index;
8835 uint_t protchk = (rw == S_READ) ? PROT_READ : PROT_WRITE;
8836 uint_t error;
8837 struct anon_map *amp;
8838 pgcnt_t anpgcnt;
8839 struct page **pplist, **pl, *pp;
8840 caddr_t a;
8841 size_t page;
8842 caddr_t lpgaddr, lpgeaddr;
8843 anon_sync_obj_t cookie;
8844 int anlock;
8845 struct anon_map *pamp;
8846 caddr_t paddr;
8847 seg_preclaim_cbfunc_t preclaim_callback;
8848 size_t pgsz;
8849 int use_pcache;
8850 size_t wlen;
8851 uint_t pflags = 0;
8852 int sftlck_sbase = 0;
8853 int sftlck_send = 0;
8854
8855 #ifdef DEBUG
8856 if (type == L_PAGELOCK && segvn_pglock_mtbf) {
8857 hrtime_t ts = gethrtime();
8858 if ((ts % segvn_pglock_mtbf) == 0) {
8859 return (ENOTSUP);
8860 }
8861 if ((ts % segvn_pglock_mtbf) == 1) {
8862 return (EFAULT);
8863 }
8864 }
8865 #endif
8866
8867 TRACE_2(TR_FAC_PHYSIO, TR_PHYSIO_SEGVN_START,
8868 "segvn_pagelock: start seg %p addr %p", seg, addr);
8869
8870 ASSERT(seg->s_as && AS_LOCK_HELD(seg->s_as));
8871 ASSERT(type == L_PAGELOCK || type == L_PAGEUNLOCK);
8872
8873 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
8874
8875 /*
8876 * for now we only support pagelock to anon memory. We would have to
8877 * check protections for vnode objects and call into the vnode driver.
8878 * That's too much for a fast path. Let the fault entry point handle
8879 * it.
8880 */
8881 if (svd->vp != NULL) {
8882 if (type == L_PAGELOCK) {
8883 error = ENOTSUP;
8884 goto out;
8885 }
8886 panic("segvn_pagelock(L_PAGEUNLOCK): vp != NULL");
8887 }
8888 if ((amp = svd->amp) == NULL) {
8889 if (type == L_PAGELOCK) {
8890 error = EFAULT;
8891 goto out;
8892 }
8893 panic("segvn_pagelock(L_PAGEUNLOCK): amp == NULL");
8894 }
8895 if (rw != S_READ && rw != S_WRITE) {
8896 if (type == L_PAGELOCK) {
8897 error = ENOTSUP;
8898 goto out;
8899 }
8900 panic("segvn_pagelock(L_PAGEUNLOCK): bad rw");
8901 }
8902
8903 if (seg->s_szc != 0) {
8904 /*
8905 * We are adjusting the pagelock region to the large page size
8906 * boundary because the unlocked part of a large page cannot
8907 * be freed anyway unless all constituent pages of a large
8908 * page are locked. Bigger regions reduce pcache chain length
8909 * and improve lookup performance. The tradeoff is that the
8910 * very first segvn_pagelock() call for a given page is more
8911 * expensive if only 1 page_t is needed for IO. This is only
8912 * an issue if pcache entry doesn't get reused by several
8913 * subsequent calls. We optimize here for the case when pcache
8914 * is heavily used by repeated IOs to the same address range.
8915 *
8916 * Note segment's page size cannot change while we are holding
8917 * as lock. And then it cannot change while softlockcnt is
8918 * not 0. This will allow us to correctly recalculate large
8919 * page size region for the matching pageunlock/reclaim call
8920 * since as_pageunlock() caller must always match
8921 * as_pagelock() call's addr and len.
8922 *
8923 * For pageunlock *ppp points to the pointer of page_t that
8924 * corresponds to the real unadjusted start address. Similar
8925 * for pagelock *ppp must point to the pointer of page_t that
8926 * corresponds to the real unadjusted start address.
8927 */
8928 pgsz = page_get_pagesize(seg->s_szc);
8929 CALC_LPG_REGION(pgsz, seg, addr, len, lpgaddr, lpgeaddr);
8930 adjustpages = btop((uintptr_t)(addr - lpgaddr));
8931 } else if (len < segvn_pglock_comb_thrshld) {
8932 lpgaddr = addr;
8933 lpgeaddr = addr + len;
8934 adjustpages = 0;
8935 pgsz = PAGESIZE;
8936 } else {
8937 /*
8938 * Align the address range of large enough requests to allow
8939 * combining of different shadow lists into 1 to reduce memory
8940 * overhead from potentially overlapping large shadow lists
8941 * (worst case is we have a 1MB IO into buffers with start
8942 * addresses separated by 4K). Alignment is only possible if
8943 * padded chunks have sufficient access permissions. Note
8944 * permissions won't change between L_PAGELOCK and
8945 * L_PAGEUNLOCK calls since non 0 softlockcnt will force
8946 * segvn_setprot() to wait until softlockcnt drops to 0. This
8947 * allows us to determine in L_PAGEUNLOCK the same range we
8948 * computed in L_PAGELOCK.
8949 *
8950 * If alignment is limited by segment ends set
8951 * sftlck_sbase/sftlck_send flags. In L_PAGELOCK case when
8952 * these flags are set bump softlockcnt_sbase/softlockcnt_send
8953 * per segment counters. In L_PAGEUNLOCK case decrease
8954 * softlockcnt_sbase/softlockcnt_send counters if
8955 * sftlck_sbase/sftlck_send flags are set. When
8956 * softlockcnt_sbase/softlockcnt_send are non 0
8957 * segvn_concat()/segvn_extend_prev()/segvn_extend_next()
8958 * won't merge the segments. This restriction combined with
8959 * restriction on segment unmapping and splitting for segments
8960 * that have non 0 softlockcnt allows L_PAGEUNLOCK to
8961 * correctly determine the same range that was previously
8962 * locked by matching L_PAGELOCK.
8963 */
8964 pflags = SEGP_PSHIFT | (segvn_pglock_comb_bshift << 16);
8965 pgsz = PAGESIZE;
8966 if (svd->type == MAP_PRIVATE) {
8967 lpgaddr = (caddr_t)P2ALIGN((uintptr_t)addr,
8968 segvn_pglock_comb_balign);
8969 if (lpgaddr < seg->s_base) {
8970 lpgaddr = seg->s_base;
8971 sftlck_sbase = 1;
8972 }
8973 } else {
8974 ulong_t aix = svd->anon_index + seg_page(seg, addr);
8975 ulong_t aaix = P2ALIGN(aix, segvn_pglock_comb_palign);
8976 if (aaix < svd->anon_index) {
8977 lpgaddr = seg->s_base;
8978 sftlck_sbase = 1;
8979 } else {
8980 lpgaddr = addr - ptob(aix - aaix);
8981 ASSERT(lpgaddr >= seg->s_base);
8982 }
8983 }
8984 if (svd->pageprot && lpgaddr != addr) {
8985 struct vpage *vp = &svd->vpage[seg_page(seg, lpgaddr)];
8986 struct vpage *evp = &svd->vpage[seg_page(seg, addr)];
8987 while (vp < evp) {
8988 if ((VPP_PROT(vp) & protchk) == 0) {
8989 break;
8990 }
8991 vp++;
8992 }
8993 if (vp < evp) {
8994 lpgaddr = addr;
8995 pflags = 0;
8996 }
8997 }
8998 lpgeaddr = addr + len;
8999 if (pflags) {
9000 if (svd->type == MAP_PRIVATE) {
9001 lpgeaddr = (caddr_t)P2ROUNDUP(
9002 (uintptr_t)lpgeaddr,
9003 segvn_pglock_comb_balign);
9004 } else {
9005 ulong_t aix = svd->anon_index +
9006 seg_page(seg, lpgeaddr);
9007 ulong_t aaix = P2ROUNDUP(aix,
9008 segvn_pglock_comb_palign);
9009 if (aaix < aix) {
9010 lpgeaddr = 0;
9011 } else {
9012 lpgeaddr += ptob(aaix - aix);
9013 }
9014 }
9015 if (lpgeaddr == 0 ||
9016 lpgeaddr > seg->s_base + seg->s_size) {
9017 lpgeaddr = seg->s_base + seg->s_size;
9018 sftlck_send = 1;
9019 }
9020 }
9021 if (svd->pageprot && lpgeaddr != addr + len) {
9022 struct vpage *vp;
9023 struct vpage *evp;
9024
9025 vp = &svd->vpage[seg_page(seg, addr + len)];
9026 evp = &svd->vpage[seg_page(seg, lpgeaddr)];
9027
9028 while (vp < evp) {
9029 if ((VPP_PROT(vp) & protchk) == 0) {
9030 break;
9031 }
9032 vp++;
9033 }
9034 if (vp < evp) {
9035 lpgeaddr = addr + len;
9036 }
9037 }
9038 adjustpages = btop((uintptr_t)(addr - lpgaddr));
9039 }
9040
9041 /*
9042 * For MAP_SHARED segments we create pcache entries tagged by amp and
9043 * anon index so that we can share pcache entries with other segments
9044 * that map this amp. For private segments pcache entries are tagged
9045 * with segment and virtual address.
9046 */
9047 if (svd->type == MAP_SHARED) {
9048 pamp = amp;
9049 paddr = (caddr_t)((lpgaddr - seg->s_base) +
9050 ptob(svd->anon_index));
9051 preclaim_callback = shamp_reclaim;
9052 } else {
9053 pamp = NULL;
9054 paddr = lpgaddr;
9055 preclaim_callback = segvn_reclaim;
9056 }
9057
9058 if (type == L_PAGEUNLOCK) {
9059 VM_STAT_ADD(segvnvmstats.pagelock[0]);
9060
9061 /*
9062 * update hat ref bits for /proc. We need to make sure
9063 * that threads tracing the ref and mod bits of the
9064 * address space get the right data.
9065 * Note: page ref and mod bits are updated at reclaim time
9066 */
9067 if (seg->s_as->a_vbits) {
9068 for (a = addr; a < addr + len; a += PAGESIZE) {
9069 if (rw == S_WRITE) {
9070 hat_setstat(seg->s_as, a,
9071 PAGESIZE, P_REF | P_MOD);
9072 } else {
9073 hat_setstat(seg->s_as, a,
9074 PAGESIZE, P_REF);
9075 }
9076 }
9077 }
9078
9079 /*
9080 * Check the shadow list entry after the last page used in
9081 * this IO request. If it's NOPCACHE_SHWLIST the shadow list
9082 * was not inserted into pcache and is not large page
9083 * adjusted. In this case call reclaim callback directly and
9084 * don't adjust the shadow list start and size for large
9085 * pages.
9086 */
9087 npages = btop(len);
9088 if ((*ppp)[npages] == NOPCACHE_SHWLIST) {
9089 void *ptag;
9090 if (pamp != NULL) {
9091 ASSERT(svd->type == MAP_SHARED);
9092 ptag = (void *)pamp;
9093 paddr = (caddr_t)((addr - seg->s_base) +
9094 ptob(svd->anon_index));
9095 } else {
9096 ptag = (void *)seg;
9097 paddr = addr;
9098 }
9099 (*preclaim_callback)(ptag, paddr, len, *ppp, rw, 0);
9100 } else {
9101 ASSERT((*ppp)[npages] == PCACHE_SHWLIST ||
9102 IS_SWAPFSVP((*ppp)[npages]->p_vnode));
9103 len = lpgeaddr - lpgaddr;
9104 npages = btop(len);
9105 seg_pinactive(seg, pamp, paddr, len,
9106 *ppp - adjustpages, rw, pflags, preclaim_callback);
9107 }
9108
9109 if (pamp != NULL) {
9110 ASSERT(svd->type == MAP_SHARED);
9111 ASSERT(svd->softlockcnt >= npages);
9112 atomic_add_long((ulong_t *)&svd->softlockcnt, -npages);
9113 }
9114
9115 if (sftlck_sbase) {
9116 ASSERT(svd->softlockcnt_sbase > 0);
9117 atomic_dec_ulong((ulong_t *)&svd->softlockcnt_sbase);
9118 }
9119 if (sftlck_send) {
9120 ASSERT(svd->softlockcnt_send > 0);
9121 atomic_dec_ulong((ulong_t *)&svd->softlockcnt_send);
9122 }
9123
9124 /*
9125 * If someone is blocked while unmapping, we purge
9126 * segment page cache and thus reclaim pplist synchronously
9127 * without waiting for seg_pasync_thread. This speeds up
9128 * unmapping in cases where munmap(2) is called, while
9129 * raw async i/o is still in progress or where a thread
9130 * exits on data fault in a multithreaded application.
9131 */
9132 if (AS_ISUNMAPWAIT(seg->s_as)) {
9133 if (svd->softlockcnt == 0) {
9134 mutex_enter(&seg->s_as->a_contents);
9135 if (AS_ISUNMAPWAIT(seg->s_as)) {
9136 AS_CLRUNMAPWAIT(seg->s_as);
9137 cv_broadcast(&seg->s_as->a_cv);
9138 }
9139 mutex_exit(&seg->s_as->a_contents);
9140 } else if (pamp == NULL) {
9141 /*
9142 * softlockcnt is not 0 and this is a
9143 * MAP_PRIVATE segment. Try to purge its
9144 * pcache entries to reduce softlockcnt.
9145 * If it drops to 0 segvn_reclaim()
9146 * will wake up a thread waiting on
9147 * unmapwait flag.
9148 *
9149 * We don't purge MAP_SHARED segments with non
9150 * 0 softlockcnt since IO is still in progress
9151 * for such segments.
9152 */
9153 ASSERT(svd->type == MAP_PRIVATE);
9154 segvn_purge(seg);
9155 }
9156 }
9157 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
9158 TRACE_2(TR_FAC_PHYSIO, TR_PHYSIO_SEGVN_UNLOCK_END,
9159 "segvn_pagelock: unlock seg %p addr %p", seg, addr);
9160 return (0);
9161 }
9162
9163 /* The L_PAGELOCK case ... */
9164
9165 VM_STAT_ADD(segvnvmstats.pagelock[1]);
9166
9167 /*
9168 * For MAP_SHARED segments we have to check protections before
9169 * seg_plookup() since pcache entries may be shared by many segments
9170 * with potentially different page protections.
9171 */
9172 if (pamp != NULL) {
9173 ASSERT(svd->type == MAP_SHARED);
9174 if (svd->pageprot == 0) {
9175 if ((svd->prot & protchk) == 0) {
9176 error = EACCES;
9177 goto out;
9178 }
9179 } else {
9180 /*
9181 * check page protections
9182 */
9183 caddr_t ea;
9184
9185 if (seg->s_szc) {
9186 a = lpgaddr;
9187 ea = lpgeaddr;
9188 } else {
9189 a = addr;
9190 ea = addr + len;
9191 }
9192 for (; a < ea; a += pgsz) {
9193 struct vpage *vp;
9194
9195 ASSERT(seg->s_szc == 0 ||
9196 sameprot(seg, a, pgsz));
9197 vp = &svd->vpage[seg_page(seg, a)];
9198 if ((VPP_PROT(vp) & protchk) == 0) {
9199 error = EACCES;
9200 goto out;
9201 }
9202 }
9203 }
9204 }
9205
9206 /*
9207 * try to find pages in segment page cache
9208 */
9209 pplist = seg_plookup(seg, pamp, paddr, lpgeaddr - lpgaddr, rw, pflags);
9210 if (pplist != NULL) {
9211 if (pamp != NULL) {
9212 npages = btop((uintptr_t)(lpgeaddr - lpgaddr));
9213 ASSERT(svd->type == MAP_SHARED);
9214 atomic_add_long((ulong_t *)&svd->softlockcnt,
9215 npages);
9216 }
9217 if (sftlck_sbase) {
9218 atomic_inc_ulong((ulong_t *)&svd->softlockcnt_sbase);
9219 }
9220 if (sftlck_send) {
9221 atomic_inc_ulong((ulong_t *)&svd->softlockcnt_send);
9222 }
9223 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
9224 *ppp = pplist + adjustpages;
9225 TRACE_2(TR_FAC_PHYSIO, TR_PHYSIO_SEGVN_HIT_END,
9226 "segvn_pagelock: cache hit seg %p addr %p", seg, addr);
9227 return (0);
9228 }
9229
9230 /*
9231 * For MAP_SHARED segments we already verified above that segment
9232 * protections allow this pagelock operation.
9233 */
9234 if (pamp == NULL) {
9235 ASSERT(svd->type == MAP_PRIVATE);
9236 if (svd->pageprot == 0) {
9237 if ((svd->prot & protchk) == 0) {
9238 error = EACCES;
9239 goto out;
9240 }
9241 if (svd->prot & PROT_WRITE) {
9242 wlen = lpgeaddr - lpgaddr;
9243 } else {
9244 wlen = 0;
9245 ASSERT(rw == S_READ);
9246 }
9247 } else {
9248 int wcont = 1;
9249 /*
9250 * check page protections
9251 */
9252 for (a = lpgaddr, wlen = 0; a < lpgeaddr; a += pgsz) {
9253 struct vpage *vp;
9254
9255 ASSERT(seg->s_szc == 0 ||
9256 sameprot(seg, a, pgsz));
9257 vp = &svd->vpage[seg_page(seg, a)];
9258 if ((VPP_PROT(vp) & protchk) == 0) {
9259 error = EACCES;
9260 goto out;
9261 }
9262 if (wcont && (VPP_PROT(vp) & PROT_WRITE)) {
9263 wlen += pgsz;
9264 } else {
9265 wcont = 0;
9266 ASSERT(rw == S_READ);
9267 }
9268 }
9269 }
9270 ASSERT(rw == S_READ || wlen == lpgeaddr - lpgaddr);
9271 ASSERT(rw == S_WRITE || wlen <= lpgeaddr - lpgaddr);
9272 }
9273
9274 /*
9275 * Only build large page adjusted shadow list if we expect to insert
9276 * it into pcache. For large enough pages it's a big overhead to
9277 * create a shadow list of the entire large page. But this overhead
9278 * should be amortized over repeated pcache hits on subsequent reuse
9279 * of this shadow list (IO into any range within this shadow list will
9280 * find it in pcache since we large page align the request for pcache
9281 * lookups). pcache performance is improved with bigger shadow lists
9282 * as it reduces the time to pcache the entire big segment and reduces
9283 * pcache chain length.
9284 */
9285 if (seg_pinsert_check(seg, pamp, paddr,
9286 lpgeaddr - lpgaddr, pflags) == SEGP_SUCCESS) {
9287 addr = lpgaddr;
9288 len = lpgeaddr - lpgaddr;
9289 use_pcache = 1;
9290 } else {
9291 use_pcache = 0;
9292 /*
9293 * Since this entry will not be inserted into the pcache, we
9294 * will not do any adjustments to the starting address or
9295 * size of the memory to be locked.
9296 */
9297 adjustpages = 0;
9298 }
9299 npages = btop(len);
9300
9301 pplist = kmem_alloc(sizeof (page_t *) * (npages + 1), KM_SLEEP);
9302 pl = pplist;
9303 *ppp = pplist + adjustpages;
9304 /*
9305 * If use_pcache is 0 this shadow list is not large page adjusted.
9306 * Record this info in the last entry of shadow array so that
9307 * L_PAGEUNLOCK can determine if it should large page adjust the
9308 * address range to find the real range that was locked.
9309 */
9310 pl[npages] = use_pcache ? PCACHE_SHWLIST : NOPCACHE_SHWLIST;
9311
9312 page = seg_page(seg, addr);
9313 anon_index = svd->anon_index + page;
9314
9315 anlock = 0;
9316 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
9317 ASSERT(amp->a_szc >= seg->s_szc);
9318 anpgcnt = page_get_pagecnt(amp->a_szc);
9319 for (a = addr; a < addr + len; a += PAGESIZE, anon_index++) {
9320 struct anon *ap;
9321 struct vnode *vp;
9322 u_offset_t off;
9323
9324 /*
9325 * Lock and unlock anon array only once per large page.
9326 * anon_array_enter() locks the root anon slot according to
9327 * a_szc which can't change while anon map is locked. We lock
9328 * anon the first time through this loop and each time we
9329 * reach anon index that corresponds to a root of a large
9330 * page.
9331 */
9332 if (a == addr || P2PHASE(anon_index, anpgcnt) == 0) {
9333 ASSERT(anlock == 0);
9334 anon_array_enter(amp, anon_index, &cookie);
9335 anlock = 1;
9336 }
9337 ap = anon_get_ptr(amp->ahp, anon_index);
9338
9339 /*
9340 * We must never use seg_pcache for COW pages
9341 * because we might end up with original page still
9342 * lying in seg_pcache even after private page is
9343 * created. This leads to data corruption as
9344 * aio_write refers to the page still in cache
9345 * while all other accesses refer to the private
9346 * page.
9347 */
9348 if (ap == NULL || ap->an_refcnt != 1) {
9349 struct vpage *vpage;
9350
9351 if (seg->s_szc) {
9352 error = EFAULT;
9353 break;
9354 }
9355 if (svd->vpage != NULL) {
9356 vpage = &svd->vpage[seg_page(seg, a)];
9357 } else {
9358 vpage = NULL;
9359 }
9360 ASSERT(anlock);
9361 anon_array_exit(&cookie);
9362 anlock = 0;
9363 pp = NULL;
9364 error = segvn_faultpage(seg->s_as->a_hat, seg, a, 0,
9365 vpage, &pp, 0, F_INVAL, rw, 1);
9366 if (error) {
9367 error = fc_decode(error);
9368 break;
9369 }
9370 anon_array_enter(amp, anon_index, &cookie);
9371 anlock = 1;
9372 ap = anon_get_ptr(amp->ahp, anon_index);
9373 if (ap == NULL || ap->an_refcnt != 1) {
9374 error = EFAULT;
9375 break;
9376 }
9377 }
9378 swap_xlate(ap, &vp, &off);
9379 pp = page_lookup_nowait(vp, off, SE_SHARED);
9380 if (pp == NULL) {
9381 error = EFAULT;
9382 break;
9383 }
9384 if (ap->an_pvp != NULL) {
9385 anon_swap_free(ap, pp);
9386 }
9387 /*
9388 * Unlock anon if this is the last slot in a large page.
9389 */
9390 if (P2PHASE(anon_index, anpgcnt) == anpgcnt - 1) {
9391 ASSERT(anlock);
9392 anon_array_exit(&cookie);
9393 anlock = 0;
9394 }
9395 *pplist++ = pp;
9396 }
9397 if (anlock) { /* Ensure the lock is dropped */
9398 anon_array_exit(&cookie);
9399 }
9400 ANON_LOCK_EXIT(&->a_rwlock);
9401
9402 if (a >= addr + len) {
9403 atomic_add_long((ulong_t *)&svd->softlockcnt, npages);
9404 if (pamp != NULL) {
9405 ASSERT(svd->type == MAP_SHARED);
9406 atomic_add_long((ulong_t *)&pamp->a_softlockcnt,
9407 npages);
9408 wlen = len;
9409 }
9410 if (sftlck_sbase) {
9411 atomic_inc_ulong((ulong_t *)&svd->softlockcnt_sbase);
9412 }
9413 if (sftlck_send) {
9414 atomic_inc_ulong((ulong_t *)&svd->softlockcnt_send);
9415 }
9416 if (use_pcache) {
9417 (void) seg_pinsert(seg, pamp, paddr, len, wlen, pl,
9418 rw, pflags, preclaim_callback);
9419 }
9420 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
9421 TRACE_2(TR_FAC_PHYSIO, TR_PHYSIO_SEGVN_FILL_END,
9422 "segvn_pagelock: cache fill seg %p addr %p", seg, addr);
9423 return (0);
9424 }
9425
9426 pplist = pl;
9427 np = ((uintptr_t)(a - addr)) >> PAGESHIFT;
9428 while (np > (uint_t)0) {
9429 ASSERT(PAGE_LOCKED(*pplist));
9430 page_unlock(*pplist);
9431 np--;
9432 pplist++;
9433 }
9434 kmem_free(pl, sizeof (page_t *) * (npages + 1));
9435 out:
9436 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
9437 *ppp = NULL;
9438 TRACE_2(TR_FAC_PHYSIO, TR_PHYSIO_SEGVN_MISS_END,
9439 "segvn_pagelock: cache miss seg %p addr %p", seg, addr);
9440 return (error);
9441 }
9442
9443 /*
9444 * purge any cached pages in the I/O page cache
9445 */
9446 static void
segvn_purge(struct seg * seg)9447 segvn_purge(struct seg *seg)
9448 {
9449 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
9450
9451 /*
9452 * pcache is only used by pure anon segments.
9453 */
9454 if (svd->amp == NULL || svd->vp != NULL) {
9455 return;
9456 }
9457
9458 /*
9459 * For MAP_SHARED segments non 0 segment's softlockcnt means
9460 * active IO is still in progress via this segment. So we only
9461 * purge MAP_SHARED segments when their softlockcnt is 0.
9462 */
9463 if (svd->type == MAP_PRIVATE) {
9464 if (svd->softlockcnt) {
9465 seg_ppurge(seg, NULL, 0);
9466 }
9467 } else if (svd->softlockcnt == 0 && svd->amp->a_softlockcnt != 0) {
9468 seg_ppurge(seg, svd->amp, 0);
9469 }
9470 }
9471
9472 /*
9473 * If async argument is not 0 we are called from pcache async thread and don't
9474 * hold AS lock.
9475 */
9476
9477 /*ARGSUSED*/
9478 static int
segvn_reclaim(void * ptag,caddr_t addr,size_t len,struct page ** pplist,enum seg_rw rw,int async)9479 segvn_reclaim(void *ptag, caddr_t addr, size_t len, struct page **pplist,
9480 enum seg_rw rw, int async)
9481 {
9482 struct seg *seg = (struct seg *)ptag;
9483 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
9484 pgcnt_t np, npages;
9485 struct page **pl;
9486
9487 npages = np = btop(len);
9488 ASSERT(npages);
9489
9490 ASSERT(svd->vp == NULL && svd->amp != NULL);
9491 ASSERT(svd->softlockcnt >= npages);
9492 ASSERT(async || AS_LOCK_HELD(seg->s_as));
9493
9494 pl = pplist;
9495
9496 ASSERT(pl[np] == NOPCACHE_SHWLIST || pl[np] == PCACHE_SHWLIST);
9497 ASSERT(!async || pl[np] == PCACHE_SHWLIST);
9498
9499 while (np > (uint_t)0) {
9500 if (rw == S_WRITE) {
9501 hat_setrefmod(*pplist);
9502 } else {
9503 hat_setref(*pplist);
9504 }
9505 page_unlock(*pplist);
9506 np--;
9507 pplist++;
9508 }
9509
9510 kmem_free(pl, sizeof (page_t *) * (npages + 1));
9511
9512 /*
9513 * If we are pcache async thread we don't hold AS lock. This means if
9514 * softlockcnt drops to 0 after the decrement below address space may
9515 * get freed. We can't allow it since after softlock derement to 0 we
9516 * still need to access as structure for possible wakeup of unmap
9517 * waiters. To prevent the disappearance of as we take this segment
9518 * segfree_syncmtx. segvn_free() also takes this mutex as a barrier to
9519 * make sure this routine completes before segment is freed.
9520 *
9521 * The second complication we have to deal with in async case is a
9522 * possibility of missed wake up of unmap wait thread. When we don't
9523 * hold as lock here we may take a_contents lock before unmap wait
9524 * thread that was first to see softlockcnt was still not 0. As a
9525 * result we'll fail to wake up an unmap wait thread. To avoid this
9526 * race we set nounmapwait flag in as structure if we drop softlockcnt
9527 * to 0 when we were called by pcache async thread. unmapwait thread
9528 * will not block if this flag is set.
9529 */
9530 if (async) {
9531 mutex_enter(&svd->segfree_syncmtx);
9532 }
9533
9534 if (!atomic_add_long_nv((ulong_t *)&svd->softlockcnt, -npages)) {
9535 if (async || AS_ISUNMAPWAIT(seg->s_as)) {
9536 mutex_enter(&seg->s_as->a_contents);
9537 if (async) {
9538 AS_SETNOUNMAPWAIT(seg->s_as);
9539 }
9540 if (AS_ISUNMAPWAIT(seg->s_as)) {
9541 AS_CLRUNMAPWAIT(seg->s_as);
9542 cv_broadcast(&seg->s_as->a_cv);
9543 }
9544 mutex_exit(&seg->s_as->a_contents);
9545 }
9546 }
9547
9548 if (async) {
9549 mutex_exit(&svd->segfree_syncmtx);
9550 }
9551 return (0);
9552 }
9553
9554 /*ARGSUSED*/
9555 static int
shamp_reclaim(void * ptag,caddr_t addr,size_t len,struct page ** pplist,enum seg_rw rw,int async)9556 shamp_reclaim(void *ptag, caddr_t addr, size_t len, struct page **pplist,
9557 enum seg_rw rw, int async)
9558 {
9559 amp_t *amp = (amp_t *)ptag;
9560 pgcnt_t np, npages;
9561 struct page **pl;
9562
9563 npages = np = btop(len);
9564 ASSERT(npages);
9565 ASSERT(amp->a_softlockcnt >= npages);
9566
9567 pl = pplist;
9568
9569 ASSERT(pl[np] == NOPCACHE_SHWLIST || pl[np] == PCACHE_SHWLIST);
9570 ASSERT(!async || pl[np] == PCACHE_SHWLIST);
9571
9572 while (np > (uint_t)0) {
9573 if (rw == S_WRITE) {
9574 hat_setrefmod(*pplist);
9575 } else {
9576 hat_setref(*pplist);
9577 }
9578 page_unlock(*pplist);
9579 np--;
9580 pplist++;
9581 }
9582
9583 kmem_free(pl, sizeof (page_t *) * (npages + 1));
9584
9585 /*
9586 * If somebody sleeps in anonmap_purge() wake them up if a_softlockcnt
9587 * drops to 0. anon map can't be freed until a_softlockcnt drops to 0
9588 * and anonmap_purge() acquires a_purgemtx.
9589 */
9590 mutex_enter(&->a_purgemtx);
9591 if (!atomic_add_long_nv((ulong_t *)&->a_softlockcnt, -npages) &&
9592 amp->a_purgewait) {
9593 amp->a_purgewait = 0;
9594 cv_broadcast(&->a_purgecv);
9595 }
9596 mutex_exit(&->a_purgemtx);
9597 return (0);
9598 }
9599
9600 /*
9601 * get a memory ID for an addr in a given segment
9602 *
9603 * XXX only creates PAGESIZE pages if anon slots are not initialized.
9604 * At fault time they will be relocated into larger pages.
9605 */
9606 static int
segvn_getmemid(struct seg * seg,caddr_t addr,memid_t * memidp)9607 segvn_getmemid(struct seg *seg, caddr_t addr, memid_t *memidp)
9608 {
9609 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
9610 struct anon *ap = NULL;
9611 ulong_t anon_index;
9612 struct anon_map *amp;
9613 anon_sync_obj_t cookie;
9614
9615 if (svd->type == MAP_PRIVATE) {
9616 memidp->val[0] = (uintptr_t)seg->s_as;
9617 memidp->val[1] = (uintptr_t)addr;
9618 return (0);
9619 }
9620
9621 if (svd->type == MAP_SHARED) {
9622 if (svd->vp) {
9623 memidp->val[0] = (uintptr_t)svd->vp;
9624 memidp->val[1] = (u_longlong_t)svd->offset +
9625 (uintptr_t)(addr - seg->s_base);
9626 return (0);
9627 } else {
9628
9629 SEGVN_LOCK_ENTER(seg->s_as, &svd->lock, RW_READER);
9630 if ((amp = svd->amp) != NULL) {
9631 anon_index = svd->anon_index +
9632 seg_page(seg, addr);
9633 }
9634 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
9635
9636 ASSERT(amp != NULL);
9637
9638 ANON_LOCK_ENTER(&->a_rwlock, RW_READER);
9639 anon_array_enter(amp, anon_index, &cookie);
9640 ap = anon_get_ptr(amp->ahp, anon_index);
9641 if (ap == NULL) {
9642 page_t *pp;
9643
9644 pp = anon_zero(seg, addr, &ap, svd->cred);
9645 if (pp == NULL) {
9646 anon_array_exit(&cookie);
9647 ANON_LOCK_EXIT(&->a_rwlock);
9648 return (ENOMEM);
9649 }
9650 ASSERT(anon_get_ptr(amp->ahp, anon_index)
9651 == NULL);
9652 (void) anon_set_ptr(amp->ahp, anon_index,
9653 ap, ANON_SLEEP);
9654 page_unlock(pp);
9655 }
9656
9657 anon_array_exit(&cookie);
9658 ANON_LOCK_EXIT(&->a_rwlock);
9659
9660 memidp->val[0] = (uintptr_t)ap;
9661 memidp->val[1] = (uintptr_t)addr & PAGEOFFSET;
9662 return (0);
9663 }
9664 }
9665 return (EINVAL);
9666 }
9667
9668 static int
sameprot(struct seg * seg,caddr_t a,size_t len)9669 sameprot(struct seg *seg, caddr_t a, size_t len)
9670 {
9671 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
9672 struct vpage *vpage;
9673 spgcnt_t pages = btop(len);
9674 uint_t prot;
9675
9676 if (svd->pageprot == 0)
9677 return (1);
9678
9679 ASSERT(svd->vpage != NULL);
9680
9681 vpage = &svd->vpage[seg_page(seg, a)];
9682 prot = VPP_PROT(vpage);
9683 vpage++;
9684 pages--;
9685 while (pages-- > 0) {
9686 if (prot != VPP_PROT(vpage))
9687 return (0);
9688 vpage++;
9689 }
9690 return (1);
9691 }
9692
9693 /*
9694 * Get memory allocation policy info for specified address in given segment
9695 */
9696 static lgrp_mem_policy_info_t *
segvn_getpolicy(struct seg * seg,caddr_t addr)9697 segvn_getpolicy(struct seg *seg, caddr_t addr)
9698 {
9699 struct anon_map *amp;
9700 ulong_t anon_index;
9701 lgrp_mem_policy_info_t *policy_info;
9702 struct segvn_data *svn_data;
9703 u_offset_t vn_off;
9704 vnode_t *vp;
9705
9706 ASSERT(seg != NULL);
9707
9708 svn_data = (struct segvn_data *)seg->s_data;
9709 if (svn_data == NULL)
9710 return (NULL);
9711
9712 /*
9713 * Get policy info for private or shared memory
9714 */
9715 if (svn_data->type != MAP_SHARED) {
9716 if (svn_data->tr_state != SEGVN_TR_ON) {
9717 policy_info = &svn_data->policy_info;
9718 } else {
9719 policy_info = &svn_data->tr_policy_info;
9720 ASSERT(policy_info->mem_policy ==
9721 LGRP_MEM_POLICY_NEXT_SEG);
9722 }
9723 } else {
9724 amp = svn_data->amp;
9725 anon_index = svn_data->anon_index + seg_page(seg, addr);
9726 vp = svn_data->vp;
9727 vn_off = svn_data->offset + (uintptr_t)(addr - seg->s_base);
9728 policy_info = lgrp_shm_policy_get(amp, anon_index, vp, vn_off);
9729 }
9730
9731 return (policy_info);
9732 }
9733
9734 /*ARGSUSED*/
9735 static int
segvn_capable(struct seg * seg,segcapability_t capability)9736 segvn_capable(struct seg *seg, segcapability_t capability)
9737 {
9738 return (0);
9739 }
9740
9741 /*
9742 * Bind text vnode segment to an amp. If we bind successfully mappings will be
9743 * established to per vnode mapping per lgroup amp pages instead of to vnode
9744 * pages. There's one amp per vnode text mapping per lgroup. Many processes
9745 * may share the same text replication amp. If a suitable amp doesn't already
9746 * exist in svntr hash table create a new one. We may fail to bind to amp if
9747 * segment is not eligible for text replication. Code below first checks for
9748 * these conditions. If binding is successful segment tr_state is set to on
9749 * and svd->amp points to the amp to use. Otherwise tr_state is set to off and
9750 * svd->amp remains as NULL.
9751 */
9752 static void
segvn_textrepl(struct seg * seg)9753 segvn_textrepl(struct seg *seg)
9754 {
9755 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
9756 vnode_t *vp = svd->vp;
9757 u_offset_t off = svd->offset;
9758 size_t size = seg->s_size;
9759 u_offset_t eoff = off + size;
9760 uint_t szc = seg->s_szc;
9761 ulong_t hash = SVNTR_HASH_FUNC(vp);
9762 svntr_t *svntrp;
9763 struct vattr va;
9764 proc_t *p = seg->s_as->a_proc;
9765 lgrp_id_t lgrp_id;
9766 lgrp_id_t olid;
9767 int first;
9768 struct anon_map *amp;
9769
9770 ASSERT(AS_LOCK_HELD(seg->s_as));
9771 ASSERT(SEGVN_WRITE_HELD(seg->s_as, &svd->lock));
9772 ASSERT(p != NULL);
9773 ASSERT(svd->tr_state == SEGVN_TR_INIT);
9774 ASSERT(!HAT_IS_REGION_COOKIE_VALID(svd->rcookie));
9775 ASSERT(svd->flags & MAP_TEXT);
9776 ASSERT(svd->type == MAP_PRIVATE);
9777 ASSERT(vp != NULL && svd->amp == NULL);
9778 ASSERT(!svd->pageprot && !(svd->prot & PROT_WRITE));
9779 ASSERT(!(svd->flags & MAP_NORESERVE) && svd->swresv == 0);
9780 ASSERT(seg->s_as != &kas);
9781 ASSERT(off < eoff);
9782 ASSERT(svntr_hashtab != NULL);
9783
9784 /*
9785 * If numa optimizations are no longer desired bail out.
9786 */
9787 if (!lgrp_optimizations()) {
9788 svd->tr_state = SEGVN_TR_OFF;
9789 return;
9790 }
9791
9792 /*
9793 * Avoid creating anon maps with size bigger than the file size.
9794 * If VOP_GETATTR() call fails bail out.
9795 */
9796 va.va_mask = AT_SIZE | AT_MTIME | AT_CTIME;
9797 if (VOP_GETATTR(vp, &va, 0, svd->cred, NULL) != 0) {
9798 svd->tr_state = SEGVN_TR_OFF;
9799 SEGVN_TR_ADDSTAT(gaerr);
9800 return;
9801 }
9802 if (btopr(va.va_size) < btopr(eoff)) {
9803 svd->tr_state = SEGVN_TR_OFF;
9804 SEGVN_TR_ADDSTAT(overmap);
9805 return;
9806 }
9807
9808 /*
9809 * VVMEXEC may not be set yet if exec() prefaults text segment. Set
9810 * this flag now before vn_is_mapped(V_WRITE) so that MAP_SHARED
9811 * mapping that checks if trcache for this vnode needs to be
9812 * invalidated can't miss us.
9813 */
9814 if (!(vp->v_flag & VVMEXEC)) {
9815 mutex_enter(&vp->v_lock);
9816 vp->v_flag |= VVMEXEC;
9817 mutex_exit(&vp->v_lock);
9818 }
9819 mutex_enter(&svntr_hashtab[hash].tr_lock);
9820 /*
9821 * Bail out if potentially MAP_SHARED writable mappings exist to this
9822 * vnode. We don't want to use old file contents from existing
9823 * replicas if this mapping was established after the original file
9824 * was changed.
9825 */
9826 if (vn_is_mapped(vp, V_WRITE)) {
9827 mutex_exit(&svntr_hashtab[hash].tr_lock);
9828 svd->tr_state = SEGVN_TR_OFF;
9829 SEGVN_TR_ADDSTAT(wrcnt);
9830 return;
9831 }
9832 svntrp = svntr_hashtab[hash].tr_head;
9833 for (; svntrp != NULL; svntrp = svntrp->tr_next) {
9834 ASSERT(svntrp->tr_refcnt != 0);
9835 if (svntrp->tr_vp != vp) {
9836 continue;
9837 }
9838
9839 /*
9840 * Bail out if the file or its attributes were changed after
9841 * this replication entry was created since we need to use the
9842 * latest file contents. Note that mtime test alone is not
9843 * sufficient because a user can explicitly change mtime via
9844 * utimes(2) interfaces back to the old value after modifiying
9845 * the file contents. To detect this case we also have to test
9846 * ctime which among other things records the time of the last
9847 * mtime change by utimes(2). ctime is not changed when the file
9848 * is only read or executed so we expect that typically existing
9849 * replication amp's can be used most of the time.
9850 */
9851 if (!svntrp->tr_valid ||
9852 svntrp->tr_mtime.tv_sec != va.va_mtime.tv_sec ||
9853 svntrp->tr_mtime.tv_nsec != va.va_mtime.tv_nsec ||
9854 svntrp->tr_ctime.tv_sec != va.va_ctime.tv_sec ||
9855 svntrp->tr_ctime.tv_nsec != va.va_ctime.tv_nsec) {
9856 mutex_exit(&svntr_hashtab[hash].tr_lock);
9857 svd->tr_state = SEGVN_TR_OFF;
9858 SEGVN_TR_ADDSTAT(stale);
9859 return;
9860 }
9861 /*
9862 * if off, eoff and szc match current segment we found the
9863 * existing entry we can use.
9864 */
9865 if (svntrp->tr_off == off && svntrp->tr_eoff == eoff &&
9866 svntrp->tr_szc == szc) {
9867 break;
9868 }
9869 /*
9870 * Don't create different but overlapping in file offsets
9871 * entries to avoid replication of the same file pages more
9872 * than once per lgroup.
9873 */
9874 if ((off >= svntrp->tr_off && off < svntrp->tr_eoff) ||
9875 (eoff > svntrp->tr_off && eoff <= svntrp->tr_eoff)) {
9876 mutex_exit(&svntr_hashtab[hash].tr_lock);
9877 svd->tr_state = SEGVN_TR_OFF;
9878 SEGVN_TR_ADDSTAT(overlap);
9879 return;
9880 }
9881 }
9882 /*
9883 * If we didn't find existing entry create a new one.
9884 */
9885 if (svntrp == NULL) {
9886 svntrp = kmem_cache_alloc(svntr_cache, KM_NOSLEEP);
9887 if (svntrp == NULL) {
9888 mutex_exit(&svntr_hashtab[hash].tr_lock);
9889 svd->tr_state = SEGVN_TR_OFF;
9890 SEGVN_TR_ADDSTAT(nokmem);
9891 return;
9892 }
9893 #ifdef DEBUG
9894 {
9895 lgrp_id_t i;
9896 for (i = 0; i < NLGRPS_MAX; i++) {
9897 ASSERT(svntrp->tr_amp[i] == NULL);
9898 }
9899 }
9900 #endif /* DEBUG */
9901 svntrp->tr_vp = vp;
9902 svntrp->tr_off = off;
9903 svntrp->tr_eoff = eoff;
9904 svntrp->tr_szc = szc;
9905 svntrp->tr_valid = 1;
9906 svntrp->tr_mtime = va.va_mtime;
9907 svntrp->tr_ctime = va.va_ctime;
9908 svntrp->tr_refcnt = 0;
9909 svntrp->tr_next = svntr_hashtab[hash].tr_head;
9910 svntr_hashtab[hash].tr_head = svntrp;
9911 }
9912 first = 1;
9913 again:
9914 /*
9915 * We want to pick a replica with pages on main thread's (t_tid = 1,
9916 * aka T1) lgrp. Currently text replication is only optimized for
9917 * workloads that either have all threads of a process on the same
9918 * lgrp or execute their large text primarily on main thread.
9919 */
9920 lgrp_id = p->p_t1_lgrpid;
9921 if (lgrp_id == LGRP_NONE) {
9922 /*
9923 * In case exec() prefaults text on non main thread use
9924 * current thread lgrpid. It will become main thread anyway
9925 * soon.
9926 */
9927 lgrp_id = lgrp_home_id(curthread);
9928 }
9929 /*
9930 * Set p_tr_lgrpid to lgrpid if it hasn't been set yet. Otherwise
9931 * just set it to NLGRPS_MAX if it's different from current process T1
9932 * home lgrp. p_tr_lgrpid is used to detect if process uses text
9933 * replication and T1 new home is different from lgrp used for text
9934 * replication. When this happens asyncronous segvn thread rechecks if
9935 * segments should change lgrps used for text replication. If we fail
9936 * to set p_tr_lgrpid with atomic_cas_32 then set it to NLGRPS_MAX
9937 * without cas if it's not already NLGRPS_MAX and not equal lgrp_id
9938 * we want to use. We don't need to use cas in this case because
9939 * another thread that races in between our non atomic check and set
9940 * may only change p_tr_lgrpid to NLGRPS_MAX at this point.
9941 */
9942 ASSERT(lgrp_id != LGRP_NONE && lgrp_id < NLGRPS_MAX);
9943 olid = p->p_tr_lgrpid;
9944 if (lgrp_id != olid && olid != NLGRPS_MAX) {
9945 lgrp_id_t nlid = (olid == LGRP_NONE) ? lgrp_id : NLGRPS_MAX;
9946 if (atomic_cas_32((uint32_t *)&p->p_tr_lgrpid, olid, nlid) !=
9947 olid) {
9948 olid = p->p_tr_lgrpid;
9949 ASSERT(olid != LGRP_NONE);
9950 if (olid != lgrp_id && olid != NLGRPS_MAX) {
9951 p->p_tr_lgrpid = NLGRPS_MAX;
9952 }
9953 }
9954 ASSERT(p->p_tr_lgrpid != LGRP_NONE);
9955 membar_producer();
9956 /*
9957 * lgrp_move_thread() won't schedule async recheck after
9958 * p->p_t1_lgrpid update unless p->p_tr_lgrpid is not
9959 * LGRP_NONE. Recheck p_t1_lgrpid once now that p->p_tr_lgrpid
9960 * is not LGRP_NONE.
9961 */
9962 if (first && p->p_t1_lgrpid != LGRP_NONE &&
9963 p->p_t1_lgrpid != lgrp_id) {
9964 first = 0;
9965 goto again;
9966 }
9967 }
9968 /*
9969 * If no amp was created yet for lgrp_id create a new one as long as
9970 * we have enough memory to afford it.
9971 */
9972 if ((amp = svntrp->tr_amp[lgrp_id]) == NULL) {
9973 size_t trmem = atomic_add_long_nv(&segvn_textrepl_bytes, size);
9974 if (trmem > segvn_textrepl_max_bytes) {
9975 SEGVN_TR_ADDSTAT(normem);
9976 goto fail;
9977 }
9978 if (anon_try_resv_zone(size, NULL) == 0) {
9979 SEGVN_TR_ADDSTAT(noanon);
9980 goto fail;
9981 }
9982 amp = anonmap_alloc(size, size, ANON_NOSLEEP);
9983 if (amp == NULL) {
9984 anon_unresv_zone(size, NULL);
9985 SEGVN_TR_ADDSTAT(nokmem);
9986 goto fail;
9987 }
9988 ASSERT(amp->refcnt == 1);
9989 amp->a_szc = szc;
9990 svntrp->tr_amp[lgrp_id] = amp;
9991 SEGVN_TR_ADDSTAT(newamp);
9992 }
9993 svntrp->tr_refcnt++;
9994 ASSERT(svd->svn_trnext == NULL);
9995 ASSERT(svd->svn_trprev == NULL);
9996 svd->svn_trnext = svntrp->tr_svnhead;
9997 svd->svn_trprev = NULL;
9998 if (svntrp->tr_svnhead != NULL) {
9999 svntrp->tr_svnhead->svn_trprev = svd;
10000 }
10001 svntrp->tr_svnhead = svd;
10002 ASSERT(amp->a_szc == szc && amp->size == size && amp->swresv == size);
10003 ASSERT(amp->refcnt >= 1);
10004 svd->amp = amp;
10005 svd->anon_index = 0;
10006 svd->tr_policy_info.mem_policy = LGRP_MEM_POLICY_NEXT_SEG;
10007 svd->tr_policy_info.mem_lgrpid = lgrp_id;
10008 svd->tr_state = SEGVN_TR_ON;
10009 mutex_exit(&svntr_hashtab[hash].tr_lock);
10010 SEGVN_TR_ADDSTAT(repl);
10011 return;
10012 fail:
10013 ASSERT(segvn_textrepl_bytes >= size);
10014 atomic_add_long(&segvn_textrepl_bytes, -size);
10015 ASSERT(svntrp != NULL);
10016 ASSERT(svntrp->tr_amp[lgrp_id] == NULL);
10017 if (svntrp->tr_refcnt == 0) {
10018 ASSERT(svntrp == svntr_hashtab[hash].tr_head);
10019 svntr_hashtab[hash].tr_head = svntrp->tr_next;
10020 mutex_exit(&svntr_hashtab[hash].tr_lock);
10021 kmem_cache_free(svntr_cache, svntrp);
10022 } else {
10023 mutex_exit(&svntr_hashtab[hash].tr_lock);
10024 }
10025 svd->tr_state = SEGVN_TR_OFF;
10026 }
10027
10028 /*
10029 * Convert seg back to regular vnode mapping seg by unbinding it from its text
10030 * replication amp. This routine is most typically called when segment is
10031 * unmapped but can also be called when segment no longer qualifies for text
10032 * replication (e.g. due to protection changes). If unload_unmap is set use
10033 * HAT_UNLOAD_UNMAP flag in hat_unload_callback(). If we are the last user of
10034 * svntr free all its anon maps and remove it from the hash table.
10035 */
10036 static void
segvn_textunrepl(struct seg * seg,int unload_unmap)10037 segvn_textunrepl(struct seg *seg, int unload_unmap)
10038 {
10039 struct segvn_data *svd = (struct segvn_data *)seg->s_data;
10040 vnode_t *vp = svd->vp;
10041 u_offset_t off = svd->offset;
10042 size_t size = seg->s_size;
10043 u_offset_t eoff = off + size;
10044 uint_t szc = seg->s_szc;
10045 ulong_t hash = SVNTR_HASH_FUNC(vp);
10046 svntr_t *svntrp;
10047 svntr_t **prv_svntrp;
10048 lgrp_id_t lgrp_id = svd->tr_policy_info.mem_lgrpid;
10049 lgrp_id_t i;
10050
10051 ASSERT(AS_LOCK_HELD(seg->s_as));
10052 ASSERT(AS_WRITE_HELD(seg->s_as) ||
10053 SEGVN_WRITE_HELD(seg->s_as, &svd->lock));
10054 ASSERT(svd->tr_state == SEGVN_TR_ON);
10055 ASSERT(!HAT_IS_REGION_COOKIE_VALID(svd->rcookie));
10056 ASSERT(svd->amp != NULL);
10057 ASSERT(svd->amp->refcnt >= 1);
10058 ASSERT(svd->anon_index == 0);
10059 ASSERT(lgrp_id != LGRP_NONE && lgrp_id < NLGRPS_MAX);
10060 ASSERT(svntr_hashtab != NULL);
10061
10062 mutex_enter(&svntr_hashtab[hash].tr_lock);
10063 prv_svntrp = &svntr_hashtab[hash].tr_head;
10064 for (; (svntrp = *prv_svntrp) != NULL; prv_svntrp = &svntrp->tr_next) {
10065 ASSERT(svntrp->tr_refcnt != 0);
10066 if (svntrp->tr_vp == vp && svntrp->tr_off == off &&
10067 svntrp->tr_eoff == eoff && svntrp->tr_szc == szc) {
10068 break;
10069 }
10070 }
10071 if (svntrp == NULL) {
10072 panic("segvn_textunrepl: svntr record not found");
10073 }
10074 if (svntrp->tr_amp[lgrp_id] != svd->amp) {
10075 panic("segvn_textunrepl: amp mismatch");
10076 }
10077 svd->tr_state = SEGVN_TR_OFF;
10078 svd->amp = NULL;
10079 if (svd->svn_trprev == NULL) {
10080 ASSERT(svntrp->tr_svnhead == svd);
10081 svntrp->tr_svnhead = svd->svn_trnext;
10082 if (svntrp->tr_svnhead != NULL) {
10083 svntrp->tr_svnhead->svn_trprev = NULL;
10084 }
10085 svd->svn_trnext = NULL;
10086 } else {
10087 svd->svn_trprev->svn_trnext = svd->svn_trnext;
10088 if (svd->svn_trnext != NULL) {
10089 svd->svn_trnext->svn_trprev = svd->svn_trprev;
10090 svd->svn_trnext = NULL;
10091 }
10092 svd->svn_trprev = NULL;
10093 }
10094 if (--svntrp->tr_refcnt) {
10095 mutex_exit(&svntr_hashtab[hash].tr_lock);
10096 goto done;
10097 }
10098 *prv_svntrp = svntrp->tr_next;
10099 mutex_exit(&svntr_hashtab[hash].tr_lock);
10100 for (i = 0; i < NLGRPS_MAX; i++) {
10101 struct anon_map *amp = svntrp->tr_amp[i];
10102 if (amp == NULL) {
10103 continue;
10104 }
10105 ASSERT(amp->refcnt == 1);
10106 ASSERT(amp->swresv == size);
10107 ASSERT(amp->size == size);
10108 ASSERT(amp->a_szc == szc);
10109 if (amp->a_szc != 0) {
10110 anon_free_pages(amp->ahp, 0, size, szc);
10111 } else {
10112 anon_free(amp->ahp, 0, size);
10113 }
10114 svntrp->tr_amp[i] = NULL;
10115 ASSERT(segvn_textrepl_bytes >= size);
10116 atomic_add_long(&segvn_textrepl_bytes, -size);
10117 anon_unresv_zone(amp->swresv, NULL);
10118 amp->refcnt = 0;
10119 anonmap_free(amp);
10120 }
10121 kmem_cache_free(svntr_cache, svntrp);
10122 done:
10123 hat_unload_callback(seg->s_as->a_hat, seg->s_base, size,
10124 unload_unmap ? HAT_UNLOAD_UNMAP : 0, NULL);
10125 }
10126
10127 /*
10128 * This is called when a MAP_SHARED writable mapping is created to a vnode
10129 * that is currently used for execution (VVMEXEC flag is set). In this case we
10130 * need to prevent further use of existing replicas.
10131 */
10132 static void
segvn_inval_trcache(vnode_t * vp)10133 segvn_inval_trcache(vnode_t *vp)
10134 {
10135 ulong_t hash = SVNTR_HASH_FUNC(vp);
10136 svntr_t *svntrp;
10137
10138 ASSERT(vp->v_flag & VVMEXEC);
10139
10140 if (svntr_hashtab == NULL) {
10141 return;
10142 }
10143
10144 mutex_enter(&svntr_hashtab[hash].tr_lock);
10145 svntrp = svntr_hashtab[hash].tr_head;
10146 for (; svntrp != NULL; svntrp = svntrp->tr_next) {
10147 ASSERT(svntrp->tr_refcnt != 0);
10148 if (svntrp->tr_vp == vp && svntrp->tr_valid) {
10149 svntrp->tr_valid = 0;
10150 }
10151 }
10152 mutex_exit(&svntr_hashtab[hash].tr_lock);
10153 }
10154
10155 static void
segvn_trasync_thread(void)10156 segvn_trasync_thread(void)
10157 {
10158 callb_cpr_t cpr_info;
10159 kmutex_t cpr_lock; /* just for CPR stuff */
10160
10161 mutex_init(&cpr_lock, NULL, MUTEX_DEFAULT, NULL);
10162
10163 CALLB_CPR_INIT(&cpr_info, &cpr_lock,
10164 callb_generic_cpr, "segvn_async");
10165
10166 if (segvn_update_textrepl_interval == 0) {
10167 segvn_update_textrepl_interval = segvn_update_tr_time * hz;
10168 } else {
10169 segvn_update_textrepl_interval *= hz;
10170 }
10171 (void) timeout(segvn_trupdate_wakeup, NULL,
10172 segvn_update_textrepl_interval);
10173
10174 for (;;) {
10175 mutex_enter(&cpr_lock);
10176 CALLB_CPR_SAFE_BEGIN(&cpr_info);
10177 mutex_exit(&cpr_lock);
10178 sema_p(&segvn_trasync_sem);
10179 mutex_enter(&cpr_lock);
10180 CALLB_CPR_SAFE_END(&cpr_info, &cpr_lock);
10181 mutex_exit(&cpr_lock);
10182 segvn_trupdate();
10183 }
10184 }
10185
10186 static uint64_t segvn_lgrp_trthr_migrs_snpsht = 0;
10187
10188 static void
segvn_trupdate_wakeup(void * dummy)10189 segvn_trupdate_wakeup(void *dummy)
10190 {
10191 uint64_t cur_lgrp_trthr_migrs = lgrp_get_trthr_migrations();
10192
10193 if (cur_lgrp_trthr_migrs != segvn_lgrp_trthr_migrs_snpsht) {
10194 segvn_lgrp_trthr_migrs_snpsht = cur_lgrp_trthr_migrs;
10195 sema_v(&segvn_trasync_sem);
10196 }
10197
10198 if (!segvn_disable_textrepl_update &&
10199 segvn_update_textrepl_interval != 0) {
10200 (void) timeout(segvn_trupdate_wakeup, dummy,
10201 segvn_update_textrepl_interval);
10202 }
10203 }
10204
10205 static void
segvn_trupdate(void)10206 segvn_trupdate(void)
10207 {
10208 ulong_t hash;
10209 svntr_t *svntrp;
10210 segvn_data_t *svd;
10211
10212 ASSERT(svntr_hashtab != NULL);
10213
10214 for (hash = 0; hash < svntr_hashtab_sz; hash++) {
10215 mutex_enter(&svntr_hashtab[hash].tr_lock);
10216 svntrp = svntr_hashtab[hash].tr_head;
10217 for (; svntrp != NULL; svntrp = svntrp->tr_next) {
10218 ASSERT(svntrp->tr_refcnt != 0);
10219 svd = svntrp->tr_svnhead;
10220 for (; svd != NULL; svd = svd->svn_trnext) {
10221 segvn_trupdate_seg(svd->seg, svd, svntrp,
10222 hash);
10223 }
10224 }
10225 mutex_exit(&svntr_hashtab[hash].tr_lock);
10226 }
10227 }
10228
10229 static void
segvn_trupdate_seg(struct seg * seg,segvn_data_t * svd,svntr_t * svntrp,ulong_t hash)10230 segvn_trupdate_seg(struct seg *seg,
10231 segvn_data_t *svd,
10232 svntr_t *svntrp,
10233 ulong_t hash)
10234 {
10235 proc_t *p;
10236 lgrp_id_t lgrp_id;
10237 struct as *as;
10238 size_t size;
10239 struct anon_map *amp;
10240
10241 ASSERT(svd->vp != NULL);
10242 ASSERT(svd->vp == svntrp->tr_vp);
10243 ASSERT(svd->offset == svntrp->tr_off);
10244 ASSERT(svd->offset + seg->s_size == svntrp->tr_eoff);
10245 ASSERT(seg != NULL);
10246 ASSERT(svd->seg == seg);
10247 ASSERT(seg->s_data == (void *)svd);
10248 ASSERT(seg->s_szc == svntrp->tr_szc);
10249 ASSERT(svd->tr_state == SEGVN_TR_ON);
10250 ASSERT(!HAT_IS_REGION_COOKIE_VALID(svd->rcookie));
10251 ASSERT(svd->amp != NULL);
10252 ASSERT(svd->tr_policy_info.mem_policy == LGRP_MEM_POLICY_NEXT_SEG);
10253 ASSERT(svd->tr_policy_info.mem_lgrpid != LGRP_NONE);
10254 ASSERT(svd->tr_policy_info.mem_lgrpid < NLGRPS_MAX);
10255 ASSERT(svntrp->tr_amp[svd->tr_policy_info.mem_lgrpid] == svd->amp);
10256 ASSERT(svntrp->tr_refcnt != 0);
10257 ASSERT(mutex_owned(&svntr_hashtab[hash].tr_lock));
10258
10259 as = seg->s_as;
10260 ASSERT(as != NULL && as != &kas);
10261 p = as->a_proc;
10262 ASSERT(p != NULL);
10263 ASSERT(p->p_tr_lgrpid != LGRP_NONE);
10264 lgrp_id = p->p_t1_lgrpid;
10265 if (lgrp_id == LGRP_NONE) {
10266 return;
10267 }
10268 ASSERT(lgrp_id < NLGRPS_MAX);
10269 if (svd->tr_policy_info.mem_lgrpid == lgrp_id) {
10270 return;
10271 }
10272
10273 /*
10274 * Use tryenter locking since we are locking as/seg and svntr hash
10275 * lock in reverse from syncrounous thread order.
10276 */
10277 if (!AS_LOCK_TRYENTER(as, RW_READER)) {
10278 SEGVN_TR_ADDSTAT(nolock);
10279 if (segvn_lgrp_trthr_migrs_snpsht) {
10280 segvn_lgrp_trthr_migrs_snpsht = 0;
10281 }
10282 return;
10283 }
10284 if (!SEGVN_LOCK_TRYENTER(seg->s_as, &svd->lock, RW_WRITER)) {
10285 AS_LOCK_EXIT(as);
10286 SEGVN_TR_ADDSTAT(nolock);
10287 if (segvn_lgrp_trthr_migrs_snpsht) {
10288 segvn_lgrp_trthr_migrs_snpsht = 0;
10289 }
10290 return;
10291 }
10292 size = seg->s_size;
10293 if (svntrp->tr_amp[lgrp_id] == NULL) {
10294 size_t trmem = atomic_add_long_nv(&segvn_textrepl_bytes, size);
10295 if (trmem > segvn_textrepl_max_bytes) {
10296 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
10297 AS_LOCK_EXIT(as);
10298 atomic_add_long(&segvn_textrepl_bytes, -size);
10299 SEGVN_TR_ADDSTAT(normem);
10300 return;
10301 }
10302 if (anon_try_resv_zone(size, NULL) == 0) {
10303 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
10304 AS_LOCK_EXIT(as);
10305 atomic_add_long(&segvn_textrepl_bytes, -size);
10306 SEGVN_TR_ADDSTAT(noanon);
10307 return;
10308 }
10309 amp = anonmap_alloc(size, size, KM_NOSLEEP);
10310 if (amp == NULL) {
10311 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
10312 AS_LOCK_EXIT(as);
10313 atomic_add_long(&segvn_textrepl_bytes, -size);
10314 anon_unresv_zone(size, NULL);
10315 SEGVN_TR_ADDSTAT(nokmem);
10316 return;
10317 }
10318 ASSERT(amp->refcnt == 1);
10319 amp->a_szc = seg->s_szc;
10320 svntrp->tr_amp[lgrp_id] = amp;
10321 }
10322 /*
10323 * We don't need to drop the bucket lock but here we give other
10324 * threads a chance. svntr and svd can't be unlinked as long as
10325 * segment lock is held as a writer and AS held as well. After we
10326 * retake bucket lock we'll continue from where we left. We'll be able
10327 * to reach the end of either list since new entries are always added
10328 * to the beginning of the lists.
10329 */
10330 mutex_exit(&svntr_hashtab[hash].tr_lock);
10331 hat_unload_callback(as->a_hat, seg->s_base, size, 0, NULL);
10332 mutex_enter(&svntr_hashtab[hash].tr_lock);
10333
10334 ASSERT(svd->tr_state == SEGVN_TR_ON);
10335 ASSERT(svd->amp != NULL);
10336 ASSERT(svd->tr_policy_info.mem_policy == LGRP_MEM_POLICY_NEXT_SEG);
10337 ASSERT(svd->tr_policy_info.mem_lgrpid != lgrp_id);
10338 ASSERT(svd->amp != svntrp->tr_amp[lgrp_id]);
10339
10340 svd->tr_policy_info.mem_lgrpid = lgrp_id;
10341 svd->amp = svntrp->tr_amp[lgrp_id];
10342 p->p_tr_lgrpid = NLGRPS_MAX;
10343 SEGVN_LOCK_EXIT(seg->s_as, &svd->lock);
10344 AS_LOCK_EXIT(as);
10345
10346 ASSERT(svntrp->tr_refcnt != 0);
10347 ASSERT(svd->vp == svntrp->tr_vp);
10348 ASSERT(svd->tr_policy_info.mem_lgrpid == lgrp_id);
10349 ASSERT(svd->amp != NULL && svd->amp == svntrp->tr_amp[lgrp_id]);
10350 ASSERT(svd->seg == seg);
10351 ASSERT(svd->tr_state == SEGVN_TR_ON);
10352
10353 SEGVN_TR_ADDSTAT(asyncrepl);
10354 }
10355