xref: /titanic_41/usr/src/uts/common/vm/seg_kmem.c (revision dd7afb26c5036958cddc0c2c1e499571664a6ed0)
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) 1998, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright 2016 Joyent, Inc.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/t_lock.h>
28 #include <sys/param.h>
29 #include <sys/sysmacros.h>
30 #include <sys/tuneable.h>
31 #include <sys/systm.h>
32 #include <sys/vm.h>
33 #include <sys/kmem.h>
34 #include <sys/vmem.h>
35 #include <sys/mman.h>
36 #include <sys/cmn_err.h>
37 #include <sys/debug.h>
38 #include <sys/dumphdr.h>
39 #include <sys/bootconf.h>
40 #include <sys/lgrp.h>
41 #include <vm/seg_kmem.h>
42 #include <vm/hat.h>
43 #include <vm/page.h>
44 #include <vm/vm_dep.h>
45 #include <vm/faultcode.h>
46 #include <sys/promif.h>
47 #include <vm/seg_kp.h>
48 #include <sys/bitmap.h>
49 #include <sys/mem_cage.h>
50 
51 #ifdef __sparc
52 #include <sys/ivintr.h>
53 #include <sys/panic.h>
54 #endif
55 
56 /*
57  * seg_kmem is the primary kernel memory segment driver.  It
58  * maps the kernel heap [kernelheap, ekernelheap), module text,
59  * and all memory which was allocated before the VM was initialized
60  * into kas.
61  *
62  * Pages which belong to seg_kmem are hashed into &kvp vnode at
63  * an offset equal to (u_offset_t)virt_addr, and have p_lckcnt >= 1.
64  * They must never be paged out since segkmem_fault() is a no-op to
65  * prevent recursive faults.
66  *
67  * Currently, seg_kmem pages are sharelocked (p_sharelock == 1) on
68  * __x86 and are unlocked (p_sharelock == 0) on __sparc.  Once __x86
69  * supports relocation the #ifdef kludges can be removed.
70  *
71  * seg_kmem pages may be subject to relocation by page_relocate(),
72  * provided that the HAT supports it; if this is so, segkmem_reloc
73  * will be set to a nonzero value. All boot time allocated memory as
74  * well as static memory is considered off limits to relocation.
75  * Pages are "relocatable" if p_state does not have P_NORELOC set, so
76  * we request P_NORELOC pages for memory that isn't safe to relocate.
77  *
78  * The kernel heap is logically divided up into four pieces:
79  *
80  *   heap32_arena is for allocations that require 32-bit absolute
81  *   virtual addresses (e.g. code that uses 32-bit pointers/offsets).
82  *
83  *   heap_core is for allocations that require 2GB *relative*
84  *   offsets; in other words all memory from heap_core is within
85  *   2GB of all other memory from the same arena. This is a requirement
86  *   of the addressing modes of some processors in supervisor code.
87  *
88  *   heap_arena is the general heap arena.
89  *
90  *   static_arena is the static memory arena.  Allocations from it
91  *   are not subject to relocation so it is safe to use the memory
92  *   physical address as well as the virtual address (e.g. the VA to
93  *   PA translations are static).  Caches may import from static_arena;
94  *   all other static memory allocations should use static_alloc_arena.
95  *
96  * On some platforms which have limited virtual address space, seg_kmem
97  * may share [kernelheap, ekernelheap) with seg_kp; if this is so,
98  * segkp_bitmap is non-NULL, and each bit represents a page of virtual
99  * address space which is actually seg_kp mapped.
100  */
101 
102 extern ulong_t *segkp_bitmap;   /* Is set if segkp is from the kernel heap */
103 
104 char *kernelheap;		/* start of primary kernel heap */
105 char *ekernelheap;		/* end of primary kernel heap */
106 struct seg kvseg;		/* primary kernel heap segment */
107 struct seg kvseg_core;		/* "core" kernel heap segment */
108 struct seg kzioseg;		/* Segment for zio mappings */
109 vmem_t *heap_arena;		/* primary kernel heap arena */
110 vmem_t *heap_core_arena;	/* core kernel heap arena */
111 char *heap_core_base;		/* start of core kernel heap arena */
112 char *heap_lp_base;		/* start of kernel large page heap arena */
113 char *heap_lp_end;		/* end of kernel large page heap arena */
114 vmem_t *hat_memload_arena;	/* HAT translation data */
115 struct seg kvseg32;		/* 32-bit kernel heap segment */
116 vmem_t *heap32_arena;		/* 32-bit kernel heap arena */
117 vmem_t *heaptext_arena;		/* heaptext arena */
118 struct as kas;			/* kernel address space */
119 int segkmem_reloc;		/* enable/disable relocatable segkmem pages */
120 vmem_t *static_arena;		/* arena for caches to import static memory */
121 vmem_t *static_alloc_arena;	/* arena for allocating static memory */
122 vmem_t *zio_arena = NULL;	/* arena for allocating zio memory */
123 vmem_t *zio_alloc_arena = NULL;	/* arena for allocating zio memory */
124 
125 /*
126  * seg_kmem driver can map part of the kernel heap with large pages.
127  * Currently this functionality is implemented for sparc platforms only.
128  *
129  * The large page size "segkmem_lpsize" for kernel heap is selected in the
130  * platform specific code. It can also be modified via /etc/system file.
131  * Setting segkmem_lpsize to PAGESIZE in /etc/system disables usage of large
132  * pages for kernel heap. "segkmem_lpshift" is adjusted appropriately to
133  * match segkmem_lpsize.
134  *
135  * At boot time we carve from kernel heap arena a range of virtual addresses
136  * that will be used for large page mappings. This range [heap_lp_base,
137  * heap_lp_end) is set up as a separate vmem arena - "heap_lp_arena". We also
138  * create "kmem_lp_arena" that caches memory already backed up by large
139  * pages. kmem_lp_arena imports virtual segments from heap_lp_arena.
140  */
141 
142 size_t	segkmem_lpsize;
143 static  uint_t	segkmem_lpshift = PAGESHIFT;
144 int	segkmem_lpszc = 0;
145 
146 size_t  segkmem_kmemlp_quantum = 0x400000;	/* 4MB */
147 size_t  segkmem_heaplp_quantum;
148 vmem_t *heap_lp_arena;
149 static  vmem_t *kmem_lp_arena;
150 static  vmem_t *segkmem_ppa_arena;
151 static	segkmem_lpcb_t segkmem_lpcb;
152 
153 /*
154  * We use "segkmem_kmemlp_max" to limit the total amount of physical memory
155  * consumed by the large page heap. By default this parameter is set to 1/8 of
156  * physmem but can be adjusted through /etc/system either directly or
157  * indirectly by setting "segkmem_kmemlp_pcnt" to the percent of physmem
158  * we allow for large page heap.
159  */
160 size_t  segkmem_kmemlp_max;
161 static  uint_t  segkmem_kmemlp_pcnt;
162 
163 /*
164  * Getting large pages for kernel heap could be problematic due to
165  * physical memory fragmentation. That's why we allow to preallocate
166  * "segkmem_kmemlp_min" bytes at boot time.
167  */
168 static  size_t	segkmem_kmemlp_min;
169 
170 /*
171  * Throttling is used to avoid expensive tries to allocate large pages
172  * for kernel heap when a lot of succesive attempts to do so fail.
173  */
174 static  ulong_t segkmem_lpthrottle_max = 0x400000;
175 static  ulong_t segkmem_lpthrottle_start = 0x40;
176 static  ulong_t segkmem_use_lpthrottle = 1;
177 
178 /*
179  * Freed pages accumulate on a garbage list until segkmem is ready,
180  * at which point we call segkmem_gc() to free it all.
181  */
182 typedef struct segkmem_gc_list {
183 	struct segkmem_gc_list	*gc_next;
184 	vmem_t			*gc_arena;
185 	size_t			gc_size;
186 } segkmem_gc_list_t;
187 
188 static segkmem_gc_list_t *segkmem_gc_list;
189 
190 /*
191  * Allocations from the hat_memload arena add VM_MEMLOAD to their
192  * vmflags so that segkmem_xalloc() can inform the hat layer that it needs
193  * to take steps to prevent infinite recursion.  HAT allocations also
194  * must be non-relocatable to prevent recursive page faults.
195  */
196 static void *
hat_memload_alloc(vmem_t * vmp,size_t size,int flags)197 hat_memload_alloc(vmem_t *vmp, size_t size, int flags)
198 {
199 	flags |= (VM_MEMLOAD | VM_NORELOC);
200 	return (segkmem_alloc(vmp, size, flags));
201 }
202 
203 /*
204  * Allocations from static_arena arena (or any other arena that uses
205  * segkmem_alloc_permanent()) require non-relocatable (permanently
206  * wired) memory pages, since these pages are referenced by physical
207  * as well as virtual address.
208  */
209 void *
segkmem_alloc_permanent(vmem_t * vmp,size_t size,int flags)210 segkmem_alloc_permanent(vmem_t *vmp, size_t size, int flags)
211 {
212 	return (segkmem_alloc(vmp, size, flags | VM_NORELOC));
213 }
214 
215 /*
216  * Initialize kernel heap boundaries.
217  */
218 void
kernelheap_init(void * heap_start,void * heap_end,char * first_avail,void * core_start,void * core_end)219 kernelheap_init(
220 	void *heap_start,
221 	void *heap_end,
222 	char *first_avail,
223 	void *core_start,
224 	void *core_end)
225 {
226 	uintptr_t textbase;
227 	size_t core_size;
228 	size_t heap_size;
229 	vmem_t *heaptext_parent;
230 	size_t	heap_lp_size = 0;
231 #ifdef __sparc
232 	size_t kmem64_sz = kmem64_aligned_end - kmem64_base;
233 #endif	/* __sparc */
234 
235 	kernelheap = heap_start;
236 	ekernelheap = heap_end;
237 
238 #ifdef __sparc
239 	heap_lp_size = (((uintptr_t)heap_end - (uintptr_t)heap_start) / 4);
240 	/*
241 	 * Bias heap_lp start address by kmem64_sz to reduce collisions
242 	 * in 4M kernel TSB between kmem64 area and heap_lp
243 	 */
244 	kmem64_sz = P2ROUNDUP(kmem64_sz, MMU_PAGESIZE256M);
245 	if (kmem64_sz <= heap_lp_size / 2)
246 		heap_lp_size -= kmem64_sz;
247 	heap_lp_base = ekernelheap - heap_lp_size;
248 	heap_lp_end = heap_lp_base + heap_lp_size;
249 #endif	/* __sparc */
250 
251 	/*
252 	 * If this platform has a 'core' heap area, then the space for
253 	 * overflow module text should be carved out of the end of that
254 	 * heap.  Otherwise, it gets carved out of the general purpose
255 	 * heap.
256 	 */
257 	core_size = (uintptr_t)core_end - (uintptr_t)core_start;
258 	if (core_size > 0) {
259 		ASSERT(core_size >= HEAPTEXT_SIZE);
260 		textbase = (uintptr_t)core_end - HEAPTEXT_SIZE;
261 		core_size -= HEAPTEXT_SIZE;
262 	}
263 #ifndef __sparc
264 	else {
265 		ekernelheap -= HEAPTEXT_SIZE;
266 		textbase = (uintptr_t)ekernelheap;
267 	}
268 #endif
269 
270 	heap_size = (uintptr_t)ekernelheap - (uintptr_t)kernelheap;
271 	heap_arena = vmem_init("heap", kernelheap, heap_size, PAGESIZE,
272 	    segkmem_alloc, segkmem_free);
273 
274 	if (core_size > 0) {
275 		heap_core_arena = vmem_create("heap_core", core_start,
276 		    core_size, PAGESIZE, NULL, NULL, NULL, 0, VM_SLEEP);
277 		heap_core_base = core_start;
278 	} else {
279 		heap_core_arena = heap_arena;
280 		heap_core_base = kernelheap;
281 	}
282 
283 	/*
284 	 * reserve space for the large page heap. If large pages for kernel
285 	 * heap is enabled large page heap arean will be created later in the
286 	 * boot sequence in segkmem_heap_lp_init(). Otherwise the allocated
287 	 * range will be returned back to the heap_arena.
288 	 */
289 	if (heap_lp_size) {
290 		(void) vmem_xalloc(heap_arena, heap_lp_size, PAGESIZE, 0, 0,
291 		    heap_lp_base, heap_lp_end,
292 		    VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
293 	}
294 
295 	/*
296 	 * Remove the already-spoken-for memory range [kernelheap, first_avail).
297 	 */
298 	(void) vmem_xalloc(heap_arena, first_avail - kernelheap, PAGESIZE,
299 	    0, 0, kernelheap, first_avail, VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
300 
301 #ifdef __sparc
302 	heap32_arena = vmem_create("heap32", (void *)SYSBASE32,
303 	    SYSLIMIT32 - SYSBASE32 - HEAPTEXT_SIZE, PAGESIZE, NULL,
304 	    NULL, NULL, 0, VM_SLEEP);
305 	/*
306 	 * Prom claims the physical and virtual resources used by panicbuf
307 	 * and inter_vec_table. So reserve space for panicbuf, intr_vec_table,
308 	 * reserved interrupt vector data structures from 32-bit heap.
309 	 */
310 	(void) vmem_xalloc(heap32_arena, PANICBUFSIZE, PAGESIZE, 0, 0,
311 	    panicbuf, panicbuf + PANICBUFSIZE,
312 	    VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
313 
314 	(void) vmem_xalloc(heap32_arena, IVSIZE, PAGESIZE, 0, 0,
315 	    intr_vec_table, (caddr_t)intr_vec_table + IVSIZE,
316 	    VM_NOSLEEP | VM_BESTFIT | VM_PANIC);
317 
318 	textbase = SYSLIMIT32 - HEAPTEXT_SIZE;
319 	heaptext_parent = NULL;
320 #else	/* __sparc */
321 	heap32_arena = heap_core_arena;
322 	heaptext_parent = heap_core_arena;
323 #endif	/* __sparc */
324 
325 	heaptext_arena = vmem_create("heaptext", (void *)textbase,
326 	    HEAPTEXT_SIZE, PAGESIZE, NULL, NULL, heaptext_parent, 0, VM_SLEEP);
327 
328 	/*
329 	 * Create a set of arenas for memory with static translations
330 	 * (e.g. VA -> PA translations cannot change).  Since using
331 	 * kernel pages by physical address implies it isn't safe to
332 	 * walk across page boundaries, the static_arena quantum must
333 	 * be PAGESIZE.  Any kmem caches that require static memory
334 	 * should source from static_arena, while direct allocations
335 	 * should only use static_alloc_arena.
336 	 */
337 	static_arena = vmem_create("static", NULL, 0, PAGESIZE,
338 	    segkmem_alloc_permanent, segkmem_free, heap_arena, 0, VM_SLEEP);
339 	static_alloc_arena = vmem_create("static_alloc", NULL, 0,
340 	    sizeof (uint64_t), vmem_alloc, vmem_free, static_arena,
341 	    0, VM_SLEEP);
342 
343 	/*
344 	 * Create an arena for translation data (ptes, hmes, or hblks).
345 	 * We need an arena for this because hat_memload() is essential
346 	 * to vmem_populate() (see comments in common/os/vmem.c).
347 	 *
348 	 * Note: any kmem cache that allocates from hat_memload_arena
349 	 * must be created as a KMC_NOHASH cache (i.e. no external slab
350 	 * and bufctl structures to allocate) so that slab creation doesn't
351 	 * require anything more than a single vmem_alloc().
352 	 */
353 	hat_memload_arena = vmem_create("hat_memload", NULL, 0, PAGESIZE,
354 	    hat_memload_alloc, segkmem_free, heap_arena, 0,
355 	    VM_SLEEP | VMC_POPULATOR | VMC_DUMPSAFE);
356 }
357 
358 void
boot_mapin(caddr_t addr,size_t size)359 boot_mapin(caddr_t addr, size_t size)
360 {
361 	caddr_t	 eaddr;
362 	page_t	*pp;
363 	pfn_t	 pfnum;
364 
365 	if (page_resv(btop(size), KM_NOSLEEP) == 0)
366 		panic("boot_mapin: page_resv failed");
367 
368 	for (eaddr = addr + size; addr < eaddr; addr += PAGESIZE) {
369 		pfnum = va_to_pfn(addr);
370 		if (pfnum == PFN_INVALID)
371 			continue;
372 		if ((pp = page_numtopp_nolock(pfnum)) == NULL)
373 			panic("boot_mapin(): No pp for pfnum = %lx", pfnum);
374 
375 		/*
376 		 * must break up any large pages that may have constituent
377 		 * pages being utilized for BOP_ALLOC()'s before calling
378 		 * page_numtopp().The locking code (ie. page_reclaim())
379 		 * can't handle them
380 		 */
381 		if (pp->p_szc != 0)
382 			page_boot_demote(pp);
383 
384 		pp = page_numtopp(pfnum, SE_EXCL);
385 		if (pp == NULL || PP_ISFREE(pp))
386 			panic("boot_alloc: pp is NULL or free");
387 
388 		/*
389 		 * If the cage is on but doesn't yet contain this page,
390 		 * mark it as non-relocatable.
391 		 */
392 		if (kcage_on && !PP_ISNORELOC(pp)) {
393 			PP_SETNORELOC(pp);
394 			PLCNT_XFER_NORELOC(pp);
395 		}
396 
397 		(void) page_hashin(pp, &kvp, (u_offset_t)(uintptr_t)addr, NULL);
398 		pp->p_lckcnt = 1;
399 #if defined(__x86)
400 		page_downgrade(pp);
401 #else
402 		page_unlock(pp);
403 #endif
404 	}
405 }
406 
407 /*
408  * Get pages from boot and hash them into the kernel's vp.
409  * Used after page structs have been allocated, but before segkmem is ready.
410  */
411 void *
boot_alloc(void * inaddr,size_t size,uint_t align)412 boot_alloc(void *inaddr, size_t size, uint_t align)
413 {
414 	caddr_t addr = inaddr;
415 
416 	if (bootops == NULL)
417 		prom_panic("boot_alloc: attempt to allocate memory after "
418 		    "BOP_GONE");
419 
420 	size = ptob(btopr(size));
421 #ifdef __sparc
422 	if (bop_alloc_chunk(addr, size, align) != (caddr_t)addr)
423 		panic("boot_alloc: bop_alloc_chunk failed");
424 #else
425 	if (BOP_ALLOC(bootops, addr, size, align) != addr)
426 		panic("boot_alloc: BOP_ALLOC failed");
427 #endif
428 	boot_mapin((caddr_t)addr, size);
429 	return (addr);
430 }
431 
432 static void
segkmem_badop()433 segkmem_badop()
434 {
435 	panic("segkmem_badop");
436 }
437 
438 #define	SEGKMEM_BADOP(t)	(t(*)())segkmem_badop
439 
440 /*ARGSUSED*/
441 static faultcode_t
segkmem_fault(struct hat * hat,struct seg * seg,caddr_t addr,size_t size,enum fault_type type,enum seg_rw rw)442 segkmem_fault(struct hat *hat, struct seg *seg, caddr_t addr, size_t size,
443 	enum fault_type type, enum seg_rw rw)
444 {
445 	pgcnt_t npages;
446 	spgcnt_t pg;
447 	page_t *pp;
448 	struct vnode *vp = seg->s_data;
449 
450 	ASSERT(RW_READ_HELD(&seg->s_as->a_lock));
451 
452 	if (seg->s_as != &kas || size > seg->s_size ||
453 	    addr < seg->s_base || addr + size > seg->s_base + seg->s_size)
454 		panic("segkmem_fault: bad args");
455 
456 	/*
457 	 * If it is one of segkp pages, call segkp_fault.
458 	 */
459 	if (segkp_bitmap && seg == &kvseg &&
460 	    BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
461 		return (SEGOP_FAULT(hat, segkp, addr, size, type, rw));
462 
463 	if (rw != S_READ && rw != S_WRITE && rw != S_OTHER)
464 		return (FC_NOSUPPORT);
465 
466 	npages = btopr(size);
467 
468 	switch (type) {
469 	case F_SOFTLOCK:	/* lock down already-loaded translations */
470 		for (pg = 0; pg < npages; pg++) {
471 			pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr,
472 			    SE_SHARED);
473 			if (pp == NULL) {
474 				/*
475 				 * Hmm, no page. Does a kernel mapping
476 				 * exist for it?
477 				 */
478 				if (!hat_probe(kas.a_hat, addr)) {
479 					addr -= PAGESIZE;
480 					while (--pg >= 0) {
481 						pp = page_find(vp, (u_offset_t)
482 						    (uintptr_t)addr);
483 						if (pp)
484 							page_unlock(pp);
485 						addr -= PAGESIZE;
486 					}
487 					return (FC_NOMAP);
488 				}
489 			}
490 			addr += PAGESIZE;
491 		}
492 		if (rw == S_OTHER)
493 			hat_reserve(seg->s_as, addr, size);
494 		return (0);
495 	case F_SOFTUNLOCK:
496 		while (npages--) {
497 			pp = page_find(vp, (u_offset_t)(uintptr_t)addr);
498 			if (pp)
499 				page_unlock(pp);
500 			addr += PAGESIZE;
501 		}
502 		return (0);
503 	default:
504 		return (FC_NOSUPPORT);
505 	}
506 	/*NOTREACHED*/
507 }
508 
509 static int
segkmem_setprot(struct seg * seg,caddr_t addr,size_t size,uint_t prot)510 segkmem_setprot(struct seg *seg, caddr_t addr, size_t size, uint_t prot)
511 {
512 	ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
513 
514 	if (seg->s_as != &kas || size > seg->s_size ||
515 	    addr < seg->s_base || addr + size > seg->s_base + seg->s_size)
516 		panic("segkmem_setprot: bad args");
517 
518 	/*
519 	 * If it is one of segkp pages, call segkp.
520 	 */
521 	if (segkp_bitmap && seg == &kvseg &&
522 	    BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
523 		return (SEGOP_SETPROT(segkp, addr, size, prot));
524 
525 	if (prot == 0)
526 		hat_unload(kas.a_hat, addr, size, HAT_UNLOAD);
527 	else
528 		hat_chgprot(kas.a_hat, addr, size, prot);
529 	return (0);
530 }
531 
532 /*
533  * This is a dummy segkmem function overloaded to call segkp
534  * when segkp is under the heap.
535  */
536 /* ARGSUSED */
537 static int
segkmem_checkprot(struct seg * seg,caddr_t addr,size_t size,uint_t prot)538 segkmem_checkprot(struct seg *seg, caddr_t addr, size_t size, uint_t prot)
539 {
540 	ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
541 
542 	if (seg->s_as != &kas)
543 		segkmem_badop();
544 
545 	/*
546 	 * If it is one of segkp pages, call into segkp.
547 	 */
548 	if (segkp_bitmap && seg == &kvseg &&
549 	    BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
550 		return (SEGOP_CHECKPROT(segkp, addr, size, prot));
551 
552 	segkmem_badop();
553 	return (0);
554 }
555 
556 /*
557  * This is a dummy segkmem function overloaded to call segkp
558  * when segkp is under the heap.
559  */
560 /* ARGSUSED */
561 static int
segkmem_kluster(struct seg * seg,caddr_t addr,ssize_t delta)562 segkmem_kluster(struct seg *seg, caddr_t addr, ssize_t delta)
563 {
564 	ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
565 
566 	if (seg->s_as != &kas)
567 		segkmem_badop();
568 
569 	/*
570 	 * If it is one of segkp pages, call into segkp.
571 	 */
572 	if (segkp_bitmap && seg == &kvseg &&
573 	    BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
574 		return (SEGOP_KLUSTER(segkp, addr, delta));
575 
576 	segkmem_badop();
577 	return (0);
578 }
579 
580 static void
segkmem_xdump_range(void * arg,void * start,size_t size)581 segkmem_xdump_range(void *arg, void *start, size_t size)
582 {
583 	struct as *as = arg;
584 	caddr_t addr = start;
585 	caddr_t addr_end = addr + size;
586 
587 	while (addr < addr_end) {
588 		pfn_t pfn = hat_getpfnum(kas.a_hat, addr);
589 		if (pfn != PFN_INVALID && pfn <= physmax && pf_is_memory(pfn))
590 			dump_addpage(as, addr, pfn);
591 		addr += PAGESIZE;
592 		dump_timeleft = dump_timeout;
593 	}
594 }
595 
596 static void
segkmem_dump_range(void * arg,void * start,size_t size)597 segkmem_dump_range(void *arg, void *start, size_t size)
598 {
599 	caddr_t addr = start;
600 	caddr_t addr_end = addr + size;
601 
602 	/*
603 	 * If we are about to start dumping the range of addresses we
604 	 * carved out of the kernel heap for the large page heap walk
605 	 * heap_lp_arena to find what segments are actually populated
606 	 */
607 	if (SEGKMEM_USE_LARGEPAGES &&
608 	    addr == heap_lp_base && addr_end == heap_lp_end &&
609 	    vmem_size(heap_lp_arena, VMEM_ALLOC) < size) {
610 		vmem_walk(heap_lp_arena, VMEM_ALLOC | VMEM_REENTRANT,
611 		    segkmem_xdump_range, arg);
612 	} else {
613 		segkmem_xdump_range(arg, start, size);
614 	}
615 }
616 
617 static void
segkmem_dump(struct seg * seg)618 segkmem_dump(struct seg *seg)
619 {
620 	/*
621 	 * The kernel's heap_arena (represented by kvseg) is a very large
622 	 * VA space, most of which is typically unused.  To speed up dumping
623 	 * we use vmem_walk() to quickly find the pieces of heap_arena that
624 	 * are actually in use.  We do the same for heap32_arena and
625 	 * heap_core.
626 	 *
627 	 * We specify VMEM_REENTRANT to vmem_walk() because dump_addpage()
628 	 * may ultimately need to allocate memory.  Reentrant walks are
629 	 * necessarily imperfect snapshots.  The kernel heap continues
630 	 * to change during a live crash dump, for example.  For a normal
631 	 * crash dump, however, we know that there won't be any other threads
632 	 * messing with the heap.  Therefore, at worst, we may fail to dump
633 	 * the pages that get allocated by the act of dumping; but we will
634 	 * always dump every page that was allocated when the walk began.
635 	 *
636 	 * The other segkmem segments are dense (fully populated), so there's
637 	 * no need to use this technique when dumping them.
638 	 *
639 	 * Note: when adding special dump handling for any new sparsely-
640 	 * populated segments, be sure to add similar handling to the ::kgrep
641 	 * code in mdb.
642 	 */
643 	if (seg == &kvseg) {
644 		vmem_walk(heap_arena, VMEM_ALLOC | VMEM_REENTRANT,
645 		    segkmem_dump_range, seg->s_as);
646 #ifndef __sparc
647 		vmem_walk(heaptext_arena, VMEM_ALLOC | VMEM_REENTRANT,
648 		    segkmem_dump_range, seg->s_as);
649 #endif
650 	} else if (seg == &kvseg_core) {
651 		vmem_walk(heap_core_arena, VMEM_ALLOC | VMEM_REENTRANT,
652 		    segkmem_dump_range, seg->s_as);
653 	} else if (seg == &kvseg32) {
654 		vmem_walk(heap32_arena, VMEM_ALLOC | VMEM_REENTRANT,
655 		    segkmem_dump_range, seg->s_as);
656 		vmem_walk(heaptext_arena, VMEM_ALLOC | VMEM_REENTRANT,
657 		    segkmem_dump_range, seg->s_as);
658 	} else if (seg == &kzioseg) {
659 		/*
660 		 * We don't want to dump pages attached to kzioseg since they
661 		 * contain file data from ZFS.  If this page's segment is
662 		 * kzioseg return instead of writing it to the dump device.
663 		 */
664 		return;
665 	} else {
666 		segkmem_dump_range(seg->s_as, seg->s_base, seg->s_size);
667 	}
668 }
669 
670 /*
671  * lock/unlock kmem pages over a given range [addr, addr+len).
672  * Returns a shadow list of pages in ppp. If there are holes
673  * in the range (e.g. some of the kernel mappings do not have
674  * underlying page_ts) returns ENOTSUP so that as_pagelock()
675  * will handle the range via as_fault(F_SOFTLOCK).
676  */
677 /*ARGSUSED*/
678 static int
segkmem_pagelock(struct seg * seg,caddr_t addr,size_t len,page_t *** ppp,enum lock_type type,enum seg_rw rw)679 segkmem_pagelock(struct seg *seg, caddr_t addr, size_t len,
680 	page_t ***ppp, enum lock_type type, enum seg_rw rw)
681 {
682 	page_t **pplist, *pp;
683 	pgcnt_t npages;
684 	spgcnt_t pg;
685 	size_t nb;
686 	struct vnode *vp = seg->s_data;
687 
688 	ASSERT(ppp != NULL);
689 
690 	/*
691 	 * If it is one of segkp pages, call into segkp.
692 	 */
693 	if (segkp_bitmap && seg == &kvseg &&
694 	    BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
695 		return (SEGOP_PAGELOCK(segkp, addr, len, ppp, type, rw));
696 
697 	npages = btopr(len);
698 	nb = sizeof (page_t *) * npages;
699 
700 	if (type == L_PAGEUNLOCK) {
701 		pplist = *ppp;
702 		ASSERT(pplist != NULL);
703 
704 		for (pg = 0; pg < npages; pg++) {
705 			pp = pplist[pg];
706 			page_unlock(pp);
707 		}
708 		kmem_free(pplist, nb);
709 		return (0);
710 	}
711 
712 	ASSERT(type == L_PAGELOCK);
713 
714 	pplist = kmem_alloc(nb, KM_NOSLEEP);
715 	if (pplist == NULL) {
716 		*ppp = NULL;
717 		return (ENOTSUP);	/* take the slow path */
718 	}
719 
720 	for (pg = 0; pg < npages; pg++) {
721 		pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr, SE_SHARED);
722 		if (pp == NULL) {
723 			while (--pg >= 0)
724 				page_unlock(pplist[pg]);
725 			kmem_free(pplist, nb);
726 			*ppp = NULL;
727 			return (ENOTSUP);
728 		}
729 		pplist[pg] = pp;
730 		addr += PAGESIZE;
731 	}
732 
733 	*ppp = pplist;
734 	return (0);
735 }
736 
737 /*
738  * This is a dummy segkmem function overloaded to call segkp
739  * when segkp is under the heap.
740  */
741 /* ARGSUSED */
742 static int
segkmem_getmemid(struct seg * seg,caddr_t addr,memid_t * memidp)743 segkmem_getmemid(struct seg *seg, caddr_t addr, memid_t *memidp)
744 {
745 	ASSERT(RW_LOCK_HELD(&seg->s_as->a_lock));
746 
747 	if (seg->s_as != &kas)
748 		segkmem_badop();
749 
750 	/*
751 	 * If it is one of segkp pages, call into segkp.
752 	 */
753 	if (segkp_bitmap && seg == &kvseg &&
754 	    BT_TEST(segkp_bitmap, btop((uintptr_t)(addr - seg->s_base))))
755 		return (SEGOP_GETMEMID(segkp, addr, memidp));
756 
757 	segkmem_badop();
758 	return (0);
759 }
760 
761 /*ARGSUSED*/
762 static lgrp_mem_policy_info_t *
segkmem_getpolicy(struct seg * seg,caddr_t addr)763 segkmem_getpolicy(struct seg *seg, caddr_t addr)
764 {
765 	return (NULL);
766 }
767 
768 /*ARGSUSED*/
769 static int
segkmem_capable(struct seg * seg,segcapability_t capability)770 segkmem_capable(struct seg *seg, segcapability_t capability)
771 {
772 	if (capability == S_CAPABILITY_NOMINFLT)
773 		return (1);
774 	return (0);
775 }
776 
777 struct seg_ops segkmem_ops = {
778 	SEGKMEM_BADOP(int),		/* dup */
779 	SEGKMEM_BADOP(int),		/* unmap */
780 	SEGKMEM_BADOP(void),		/* free */
781 	segkmem_fault,
782 	SEGKMEM_BADOP(faultcode_t),	/* faulta */
783 	segkmem_setprot,
784 	segkmem_checkprot,
785 	segkmem_kluster,
786 	SEGKMEM_BADOP(size_t),		/* swapout */
787 	SEGKMEM_BADOP(int),		/* sync */
788 	SEGKMEM_BADOP(size_t),		/* incore */
789 	SEGKMEM_BADOP(int),		/* lockop */
790 	SEGKMEM_BADOP(int),		/* getprot */
791 	SEGKMEM_BADOP(u_offset_t),	/* getoffset */
792 	SEGKMEM_BADOP(int),		/* gettype */
793 	SEGKMEM_BADOP(int),		/* getvp */
794 	SEGKMEM_BADOP(int),		/* advise */
795 	segkmem_dump,
796 	segkmem_pagelock,
797 	SEGKMEM_BADOP(int),		/* setpgsz */
798 	segkmem_getmemid,
799 	segkmem_getpolicy,		/* getpolicy */
800 	segkmem_capable,		/* capable */
801 	seg_inherit_notsup		/* inherit */
802 };
803 
804 int
segkmem_zio_create(struct seg * seg)805 segkmem_zio_create(struct seg *seg)
806 {
807 	ASSERT(seg->s_as == &kas && RW_WRITE_HELD(&kas.a_lock));
808 	seg->s_ops = &segkmem_ops;
809 	seg->s_data = &zvp;
810 	kas.a_size += seg->s_size;
811 	return (0);
812 }
813 
814 int
segkmem_create(struct seg * seg)815 segkmem_create(struct seg *seg)
816 {
817 	ASSERT(seg->s_as == &kas && RW_WRITE_HELD(&kas.a_lock));
818 	seg->s_ops = &segkmem_ops;
819 	seg->s_data = &kvp;
820 	kas.a_size += seg->s_size;
821 	return (0);
822 }
823 
824 /*ARGSUSED*/
825 page_t *
segkmem_page_create(void * addr,size_t size,int vmflag,void * arg)826 segkmem_page_create(void *addr, size_t size, int vmflag, void *arg)
827 {
828 	struct seg kseg;
829 	int pgflags;
830 	struct vnode *vp = arg;
831 
832 	if (vp == NULL)
833 		vp = &kvp;
834 
835 	kseg.s_as = &kas;
836 	pgflags = PG_EXCL;
837 
838 	if (segkmem_reloc == 0 || (vmflag & VM_NORELOC))
839 		pgflags |= PG_NORELOC;
840 	if ((vmflag & VM_NOSLEEP) == 0)
841 		pgflags |= PG_WAIT;
842 	if (vmflag & VM_PANIC)
843 		pgflags |= PG_PANIC;
844 	if (vmflag & VM_PUSHPAGE)
845 		pgflags |= PG_PUSHPAGE;
846 	if (vmflag & VM_NORMALPRI) {
847 		ASSERT(vmflag & VM_NOSLEEP);
848 		pgflags |= PG_NORMALPRI;
849 	}
850 
851 	return (page_create_va(vp, (u_offset_t)(uintptr_t)addr, size,
852 	    pgflags, &kseg, addr));
853 }
854 
855 /*
856  * Allocate pages to back the virtual address range [addr, addr + size).
857  * If addr is NULL, allocate the virtual address space as well.
858  */
859 void *
segkmem_xalloc(vmem_t * vmp,void * inaddr,size_t size,int vmflag,uint_t attr,page_t * (* page_create_func)(void *,size_t,int,void *),void * pcarg)860 segkmem_xalloc(vmem_t *vmp, void *inaddr, size_t size, int vmflag, uint_t attr,
861 	page_t *(*page_create_func)(void *, size_t, int, void *), void *pcarg)
862 {
863 	page_t *ppl;
864 	caddr_t addr = inaddr;
865 	pgcnt_t npages = btopr(size);
866 	int allocflag;
867 
868 	if (inaddr == NULL && (addr = vmem_alloc(vmp, size, vmflag)) == NULL)
869 		return (NULL);
870 
871 	ASSERT(((uintptr_t)addr & PAGEOFFSET) == 0);
872 
873 	if (page_resv(npages, vmflag & VM_KMFLAGS) == 0) {
874 		if (inaddr == NULL)
875 			vmem_free(vmp, addr, size);
876 		return (NULL);
877 	}
878 
879 	ppl = page_create_func(addr, size, vmflag, pcarg);
880 	if (ppl == NULL) {
881 		if (inaddr == NULL)
882 			vmem_free(vmp, addr, size);
883 		page_unresv(npages);
884 		return (NULL);
885 	}
886 
887 	/*
888 	 * Under certain conditions, we need to let the HAT layer know
889 	 * that it cannot safely allocate memory.  Allocations from
890 	 * the hat_memload vmem arena always need this, to prevent
891 	 * infinite recursion.
892 	 *
893 	 * In addition, the x86 hat cannot safely do memory
894 	 * allocations while in vmem_populate(), because there
895 	 * is no simple bound on its usage.
896 	 */
897 	if (vmflag & VM_MEMLOAD)
898 		allocflag = HAT_NO_KALLOC;
899 #if defined(__x86)
900 	else if (vmem_is_populator())
901 		allocflag = HAT_NO_KALLOC;
902 #endif
903 	else
904 		allocflag = 0;
905 
906 	while (ppl != NULL) {
907 		page_t *pp = ppl;
908 		page_sub(&ppl, pp);
909 		ASSERT(page_iolock_assert(pp));
910 		ASSERT(PAGE_EXCL(pp));
911 		page_io_unlock(pp);
912 		hat_memload(kas.a_hat, (caddr_t)(uintptr_t)pp->p_offset, pp,
913 		    (PROT_ALL & ~PROT_USER) | HAT_NOSYNC | attr,
914 		    HAT_LOAD_LOCK | allocflag);
915 		pp->p_lckcnt = 1;
916 #if defined(__x86)
917 		page_downgrade(pp);
918 #else
919 		if (vmflag & SEGKMEM_SHARELOCKED)
920 			page_downgrade(pp);
921 		else
922 			page_unlock(pp);
923 #endif
924 	}
925 
926 	return (addr);
927 }
928 
929 static void *
segkmem_alloc_vn(vmem_t * vmp,size_t size,int vmflag,struct vnode * vp)930 segkmem_alloc_vn(vmem_t *vmp, size_t size, int vmflag, struct vnode *vp)
931 {
932 	void *addr;
933 	segkmem_gc_list_t *gcp, **prev_gcpp;
934 
935 	ASSERT(vp != NULL);
936 
937 	if (kvseg.s_base == NULL) {
938 #ifndef __sparc
939 		if (bootops->bsys_alloc == NULL)
940 			halt("Memory allocation between bop_alloc() and "
941 			    "kmem_alloc().\n");
942 #endif
943 
944 		/*
945 		 * There's not a lot of memory to go around during boot,
946 		 * so recycle it if we can.
947 		 */
948 		for (prev_gcpp = &segkmem_gc_list; (gcp = *prev_gcpp) != NULL;
949 		    prev_gcpp = &gcp->gc_next) {
950 			if (gcp->gc_arena == vmp && gcp->gc_size == size) {
951 				*prev_gcpp = gcp->gc_next;
952 				return (gcp);
953 			}
954 		}
955 
956 		addr = vmem_alloc(vmp, size, vmflag | VM_PANIC);
957 		if (boot_alloc(addr, size, BO_NO_ALIGN) != addr)
958 			panic("segkmem_alloc: boot_alloc failed");
959 		return (addr);
960 	}
961 	return (segkmem_xalloc(vmp, NULL, size, vmflag, 0,
962 	    segkmem_page_create, vp));
963 }
964 
965 void *
segkmem_alloc(vmem_t * vmp,size_t size,int vmflag)966 segkmem_alloc(vmem_t *vmp, size_t size, int vmflag)
967 {
968 	return (segkmem_alloc_vn(vmp, size, vmflag, &kvp));
969 }
970 
971 void *
segkmem_zio_alloc(vmem_t * vmp,size_t size,int vmflag)972 segkmem_zio_alloc(vmem_t *vmp, size_t size, int vmflag)
973 {
974 	return (segkmem_alloc_vn(vmp, size, vmflag, &zvp));
975 }
976 
977 /*
978  * Any changes to this routine must also be carried over to
979  * devmap_free_pages() in the seg_dev driver. This is because
980  * we currently don't have a special kernel segment for non-paged
981  * kernel memory that is exported by drivers to user space.
982  */
983 static void
segkmem_free_vn(vmem_t * vmp,void * inaddr,size_t size,struct vnode * vp,void (* func)(page_t *))984 segkmem_free_vn(vmem_t *vmp, void *inaddr, size_t size, struct vnode *vp,
985     void (*func)(page_t *))
986 {
987 	page_t *pp;
988 	caddr_t addr = inaddr;
989 	caddr_t eaddr;
990 	pgcnt_t npages = btopr(size);
991 
992 	ASSERT(((uintptr_t)addr & PAGEOFFSET) == 0);
993 	ASSERT(vp != NULL);
994 
995 	if (kvseg.s_base == NULL) {
996 		segkmem_gc_list_t *gc = inaddr;
997 		gc->gc_arena = vmp;
998 		gc->gc_size = size;
999 		gc->gc_next = segkmem_gc_list;
1000 		segkmem_gc_list = gc;
1001 		return;
1002 	}
1003 
1004 	hat_unload(kas.a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1005 
1006 	for (eaddr = addr + size; addr < eaddr; addr += PAGESIZE) {
1007 #if defined(__x86)
1008 		pp = page_find(vp, (u_offset_t)(uintptr_t)addr);
1009 		if (pp == NULL)
1010 			panic("segkmem_free: page not found");
1011 		if (!page_tryupgrade(pp)) {
1012 			/*
1013 			 * Some other thread has a sharelock. Wait for
1014 			 * it to drop the lock so we can free this page.
1015 			 */
1016 			page_unlock(pp);
1017 			pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr,
1018 			    SE_EXCL);
1019 		}
1020 #else
1021 		pp = page_lookup(vp, (u_offset_t)(uintptr_t)addr, SE_EXCL);
1022 #endif
1023 		if (pp == NULL)
1024 			panic("segkmem_free: page not found");
1025 		/* Clear p_lckcnt so page_destroy() doesn't update availrmem */
1026 		pp->p_lckcnt = 0;
1027 		if (func)
1028 			func(pp);
1029 		else
1030 			page_destroy(pp, 0);
1031 	}
1032 	if (func == NULL)
1033 		page_unresv(npages);
1034 
1035 	if (vmp != NULL)
1036 		vmem_free(vmp, inaddr, size);
1037 
1038 }
1039 
1040 void
segkmem_xfree(vmem_t * vmp,void * inaddr,size_t size,void (* func)(page_t *))1041 segkmem_xfree(vmem_t *vmp, void *inaddr, size_t size, void (*func)(page_t *))
1042 {
1043 	segkmem_free_vn(vmp, inaddr, size, &kvp, func);
1044 }
1045 
1046 void
segkmem_free(vmem_t * vmp,void * inaddr,size_t size)1047 segkmem_free(vmem_t *vmp, void *inaddr, size_t size)
1048 {
1049 	segkmem_free_vn(vmp, inaddr, size, &kvp, NULL);
1050 }
1051 
1052 void
segkmem_zio_free(vmem_t * vmp,void * inaddr,size_t size)1053 segkmem_zio_free(vmem_t *vmp, void *inaddr, size_t size)
1054 {
1055 	segkmem_free_vn(vmp, inaddr, size, &zvp, NULL);
1056 }
1057 
1058 void
segkmem_gc(void)1059 segkmem_gc(void)
1060 {
1061 	ASSERT(kvseg.s_base != NULL);
1062 	while (segkmem_gc_list != NULL) {
1063 		segkmem_gc_list_t *gc = segkmem_gc_list;
1064 		segkmem_gc_list = gc->gc_next;
1065 		segkmem_free(gc->gc_arena, gc, gc->gc_size);
1066 	}
1067 }
1068 
1069 /*
1070  * Legacy entry points from here to end of file.
1071  */
1072 void
segkmem_mapin(struct seg * seg,void * addr,size_t size,uint_t vprot,pfn_t pfn,uint_t flags)1073 segkmem_mapin(struct seg *seg, void *addr, size_t size, uint_t vprot,
1074     pfn_t pfn, uint_t flags)
1075 {
1076 	hat_unload(seg->s_as->a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1077 	hat_devload(seg->s_as->a_hat, addr, size, pfn, vprot,
1078 	    flags | HAT_LOAD_LOCK);
1079 }
1080 
1081 void
segkmem_mapout(struct seg * seg,void * addr,size_t size)1082 segkmem_mapout(struct seg *seg, void *addr, size_t size)
1083 {
1084 	hat_unload(seg->s_as->a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1085 }
1086 
1087 void *
kmem_getpages(pgcnt_t npages,int kmflag)1088 kmem_getpages(pgcnt_t npages, int kmflag)
1089 {
1090 	return (kmem_alloc(ptob(npages), kmflag));
1091 }
1092 
1093 void
kmem_freepages(void * addr,pgcnt_t npages)1094 kmem_freepages(void *addr, pgcnt_t npages)
1095 {
1096 	kmem_free(addr, ptob(npages));
1097 }
1098 
1099 /*
1100  * segkmem_page_create_large() allocates a large page to be used for the kmem
1101  * caches. If kpr is enabled we ask for a relocatable page unless requested
1102  * otherwise. If kpr is disabled we have to ask for a non-reloc page
1103  */
1104 static page_t *
segkmem_page_create_large(void * addr,size_t size,int vmflag,void * arg)1105 segkmem_page_create_large(void *addr, size_t size, int vmflag, void *arg)
1106 {
1107 	int pgflags;
1108 
1109 	pgflags = PG_EXCL;
1110 
1111 	if (segkmem_reloc == 0 || (vmflag & VM_NORELOC))
1112 		pgflags |= PG_NORELOC;
1113 	if (!(vmflag & VM_NOSLEEP))
1114 		pgflags |= PG_WAIT;
1115 	if (vmflag & VM_PUSHPAGE)
1116 		pgflags |= PG_PUSHPAGE;
1117 	if (vmflag & VM_NORMALPRI)
1118 		pgflags |= PG_NORMALPRI;
1119 
1120 	return (page_create_va_large(&kvp, (u_offset_t)(uintptr_t)addr, size,
1121 	    pgflags, &kvseg, addr, arg));
1122 }
1123 
1124 /*
1125  * Allocate a large page to back the virtual address range
1126  * [addr, addr + size).  If addr is NULL, allocate the virtual address
1127  * space as well.
1128  */
1129 static void *
segkmem_xalloc_lp(vmem_t * vmp,void * inaddr,size_t size,int vmflag,uint_t attr,page_t * (* page_create_func)(void *,size_t,int,void *),void * pcarg)1130 segkmem_xalloc_lp(vmem_t *vmp, void *inaddr, size_t size, int vmflag,
1131     uint_t attr, page_t *(*page_create_func)(void *, size_t, int, void *),
1132     void *pcarg)
1133 {
1134 	caddr_t addr = inaddr, pa;
1135 	size_t  lpsize = segkmem_lpsize;
1136 	pgcnt_t npages = btopr(size);
1137 	pgcnt_t nbpages = btop(lpsize);
1138 	pgcnt_t nlpages = size >> segkmem_lpshift;
1139 	size_t  ppasize = nbpages * sizeof (page_t *);
1140 	page_t *pp, *rootpp, **ppa, *pplist = NULL;
1141 	int i;
1142 
1143 	vmflag |= VM_NOSLEEP;
1144 
1145 	if (page_resv(npages, vmflag & VM_KMFLAGS) == 0) {
1146 		return (NULL);
1147 	}
1148 
1149 	/*
1150 	 * allocate an array we need for hat_memload_array.
1151 	 * we use a separate arena to avoid recursion.
1152 	 * we will not need this array when hat_memload_array learns pp++
1153 	 */
1154 	if ((ppa = vmem_alloc(segkmem_ppa_arena, ppasize, vmflag)) == NULL) {
1155 		goto fail_array_alloc;
1156 	}
1157 
1158 	if (inaddr == NULL && (addr = vmem_alloc(vmp, size, vmflag)) == NULL)
1159 		goto fail_vmem_alloc;
1160 
1161 	ASSERT(((uintptr_t)addr & (lpsize - 1)) == 0);
1162 
1163 	/* create all the pages */
1164 	for (pa = addr, i = 0; i < nlpages; i++, pa += lpsize) {
1165 		if ((pp = page_create_func(pa, lpsize, vmflag, pcarg)) == NULL)
1166 			goto fail_page_create;
1167 		page_list_concat(&pplist, &pp);
1168 	}
1169 
1170 	/* at this point we have all the resource to complete the request */
1171 	while ((rootpp = pplist) != NULL) {
1172 		for (i = 0; i < nbpages; i++) {
1173 			ASSERT(pplist != NULL);
1174 			pp = pplist;
1175 			page_sub(&pplist, pp);
1176 			ASSERT(page_iolock_assert(pp));
1177 			page_io_unlock(pp);
1178 			ppa[i] = pp;
1179 		}
1180 		/*
1181 		 * Load the locked entry. It's OK to preload the entry into the
1182 		 * TSB since we now support large mappings in the kernel TSB.
1183 		 */
1184 		hat_memload_array(kas.a_hat,
1185 		    (caddr_t)(uintptr_t)rootpp->p_offset, lpsize,
1186 		    ppa, (PROT_ALL & ~PROT_USER) | HAT_NOSYNC | attr,
1187 		    HAT_LOAD_LOCK);
1188 
1189 		for (--i; i >= 0; --i) {
1190 			ppa[i]->p_lckcnt = 1;
1191 			page_unlock(ppa[i]);
1192 		}
1193 	}
1194 
1195 	vmem_free(segkmem_ppa_arena, ppa, ppasize);
1196 	return (addr);
1197 
1198 fail_page_create:
1199 	while ((rootpp = pplist) != NULL) {
1200 		for (i = 0, pp = pplist; i < nbpages; i++, pp = pplist) {
1201 			ASSERT(pp != NULL);
1202 			page_sub(&pplist, pp);
1203 			ASSERT(page_iolock_assert(pp));
1204 			page_io_unlock(pp);
1205 		}
1206 		page_destroy_pages(rootpp);
1207 	}
1208 
1209 	if (inaddr == NULL)
1210 		vmem_free(vmp, addr, size);
1211 
1212 fail_vmem_alloc:
1213 	vmem_free(segkmem_ppa_arena, ppa, ppasize);
1214 
1215 fail_array_alloc:
1216 	page_unresv(npages);
1217 
1218 	return (NULL);
1219 }
1220 
1221 static void
segkmem_free_one_lp(caddr_t addr,size_t size)1222 segkmem_free_one_lp(caddr_t addr, size_t size)
1223 {
1224 	page_t		*pp, *rootpp = NULL;
1225 	pgcnt_t 	pgs_left = btopr(size);
1226 
1227 	ASSERT(size == segkmem_lpsize);
1228 
1229 	hat_unload(kas.a_hat, addr, size, HAT_UNLOAD_UNLOCK);
1230 
1231 	for (; pgs_left > 0; addr += PAGESIZE, pgs_left--) {
1232 		pp = page_lookup(&kvp, (u_offset_t)(uintptr_t)addr, SE_EXCL);
1233 		if (pp == NULL)
1234 			panic("segkmem_free_one_lp: page not found");
1235 		ASSERT(PAGE_EXCL(pp));
1236 		pp->p_lckcnt = 0;
1237 		if (rootpp == NULL)
1238 			rootpp = pp;
1239 	}
1240 	ASSERT(rootpp != NULL);
1241 	page_destroy_pages(rootpp);
1242 
1243 	/* page_unresv() is done by the caller */
1244 }
1245 
1246 /*
1247  * This function is called to import new spans into the vmem arenas like
1248  * kmem_default_arena and kmem_oversize_arena. It first tries to import
1249  * spans from large page arena - kmem_lp_arena. In order to do this it might
1250  * have to "upgrade the requested size" to kmem_lp_arena quantum. If
1251  * it was not able to satisfy the upgraded request it then calls regular
1252  * segkmem_alloc() that satisfies the request by importing from "*vmp" arena
1253  */
1254 /*ARGSUSED*/
1255 void *
segkmem_alloc_lp(vmem_t * vmp,size_t * sizep,size_t align,int vmflag)1256 segkmem_alloc_lp(vmem_t *vmp, size_t *sizep, size_t align, int vmflag)
1257 {
1258 	size_t size;
1259 	kthread_t *t = curthread;
1260 	segkmem_lpcb_t *lpcb = &segkmem_lpcb;
1261 
1262 	ASSERT(sizep != NULL);
1263 
1264 	size = *sizep;
1265 
1266 	if (lpcb->lp_uselp && !(t->t_flag & T_PANIC) &&
1267 	    !(vmflag & SEGKMEM_SHARELOCKED)) {
1268 
1269 		size_t kmemlp_qnt = segkmem_kmemlp_quantum;
1270 		size_t asize = P2ROUNDUP(size, kmemlp_qnt);
1271 		void  *addr = NULL;
1272 		ulong_t *lpthrtp = &lpcb->lp_throttle;
1273 		ulong_t lpthrt = *lpthrtp;
1274 		int	dowakeup = 0;
1275 		int	doalloc = 1;
1276 
1277 		ASSERT(kmem_lp_arena != NULL);
1278 		ASSERT(asize >= size);
1279 
1280 		if (lpthrt != 0) {
1281 			/* try to update the throttle value */
1282 			lpthrt = atomic_inc_ulong_nv(lpthrtp);
1283 			if (lpthrt >= segkmem_lpthrottle_max) {
1284 				lpthrt = atomic_cas_ulong(lpthrtp, lpthrt,
1285 				    segkmem_lpthrottle_max / 4);
1286 			}
1287 
1288 			/*
1289 			 * when we get above throttle start do an exponential
1290 			 * backoff at trying large pages and reaping
1291 			 */
1292 			if (lpthrt > segkmem_lpthrottle_start &&
1293 			    !ISP2(lpthrt)) {
1294 				lpcb->allocs_throttled++;
1295 				lpthrt--;
1296 				if (ISP2(lpthrt))
1297 					kmem_reap();
1298 				return (segkmem_alloc(vmp, size, vmflag));
1299 			}
1300 		}
1301 
1302 		if (!(vmflag & VM_NOSLEEP) &&
1303 		    segkmem_heaplp_quantum >= (8 * kmemlp_qnt) &&
1304 		    vmem_size(kmem_lp_arena, VMEM_FREE) <= kmemlp_qnt &&
1305 		    asize < (segkmem_heaplp_quantum - kmemlp_qnt)) {
1306 
1307 			/*
1308 			 * we are low on free memory in kmem_lp_arena
1309 			 * we let only one guy to allocate heap_lp
1310 			 * quantum size chunk that everybody is going to
1311 			 * share
1312 			 */
1313 			mutex_enter(&lpcb->lp_lock);
1314 
1315 			if (lpcb->lp_wait) {
1316 
1317 				/* we are not the first one - wait */
1318 				cv_wait(&lpcb->lp_cv, &lpcb->lp_lock);
1319 				if (vmem_size(kmem_lp_arena, VMEM_FREE) <
1320 				    kmemlp_qnt)  {
1321 					doalloc = 0;
1322 				}
1323 			} else if (vmem_size(kmem_lp_arena, VMEM_FREE) <=
1324 			    kmemlp_qnt) {
1325 
1326 				/*
1327 				 * we are the first one, make sure we import
1328 				 * a large page
1329 				 */
1330 				if (asize == kmemlp_qnt)
1331 					asize += kmemlp_qnt;
1332 				dowakeup = 1;
1333 				lpcb->lp_wait = 1;
1334 			}
1335 
1336 			mutex_exit(&lpcb->lp_lock);
1337 		}
1338 
1339 		/*
1340 		 * VM_ABORT flag prevents sleeps in vmem_xalloc when
1341 		 * large pages are not available. In that case this allocation
1342 		 * attempt will fail and we will retry allocation with small
1343 		 * pages. We also do not want to panic if this allocation fails
1344 		 * because we are going to retry.
1345 		 */
1346 		if (doalloc) {
1347 			addr = vmem_alloc(kmem_lp_arena, asize,
1348 			    (vmflag | VM_ABORT) & ~VM_PANIC);
1349 
1350 			if (dowakeup) {
1351 				mutex_enter(&lpcb->lp_lock);
1352 				ASSERT(lpcb->lp_wait != 0);
1353 				lpcb->lp_wait = 0;
1354 				cv_broadcast(&lpcb->lp_cv);
1355 				mutex_exit(&lpcb->lp_lock);
1356 			}
1357 		}
1358 
1359 		if (addr != NULL) {
1360 			*sizep = asize;
1361 			*lpthrtp = 0;
1362 			return (addr);
1363 		}
1364 
1365 		if (vmflag & VM_NOSLEEP)
1366 			lpcb->nosleep_allocs_failed++;
1367 		else
1368 			lpcb->sleep_allocs_failed++;
1369 		lpcb->alloc_bytes_failed += size;
1370 
1371 		/* if large page throttling is not started yet do it */
1372 		if (segkmem_use_lpthrottle && lpthrt == 0) {
1373 			lpthrt = atomic_cas_ulong(lpthrtp, lpthrt, 1);
1374 		}
1375 	}
1376 	return (segkmem_alloc(vmp, size, vmflag));
1377 }
1378 
1379 void
segkmem_free_lp(vmem_t * vmp,void * inaddr,size_t size)1380 segkmem_free_lp(vmem_t *vmp, void *inaddr, size_t size)
1381 {
1382 	if (kmem_lp_arena == NULL || !IS_KMEM_VA_LARGEPAGE((caddr_t)inaddr)) {
1383 		segkmem_free(vmp, inaddr, size);
1384 	} else {
1385 		vmem_free(kmem_lp_arena, inaddr, size);
1386 	}
1387 }
1388 
1389 /*
1390  * segkmem_alloc_lpi() imports virtual memory from large page heap arena
1391  * into kmem_lp arena. In the process it maps the imported segment with
1392  * large pages
1393  */
1394 static void *
segkmem_alloc_lpi(vmem_t * vmp,size_t size,int vmflag)1395 segkmem_alloc_lpi(vmem_t *vmp, size_t size, int vmflag)
1396 {
1397 	segkmem_lpcb_t *lpcb = &segkmem_lpcb;
1398 	void  *addr;
1399 
1400 	ASSERT(size != 0);
1401 	ASSERT(vmp == heap_lp_arena);
1402 
1403 	/* do not allow large page heap grow beyound limits */
1404 	if (vmem_size(vmp, VMEM_ALLOC) >= segkmem_kmemlp_max) {
1405 		lpcb->allocs_limited++;
1406 		return (NULL);
1407 	}
1408 
1409 	addr = segkmem_xalloc_lp(vmp, NULL, size, vmflag, 0,
1410 	    segkmem_page_create_large, NULL);
1411 	return (addr);
1412 }
1413 
1414 /*
1415  * segkmem_free_lpi() returns virtual memory back into large page heap arena
1416  * from kmem_lp arena. Beore doing this it unmaps the segment and frees
1417  * large pages used to map it.
1418  */
1419 static void
segkmem_free_lpi(vmem_t * vmp,void * inaddr,size_t size)1420 segkmem_free_lpi(vmem_t *vmp, void *inaddr, size_t size)
1421 {
1422 	pgcnt_t		nlpages = size >> segkmem_lpshift;
1423 	size_t		lpsize = segkmem_lpsize;
1424 	caddr_t		addr = inaddr;
1425 	pgcnt_t 	npages = btopr(size);
1426 	int		i;
1427 
1428 	ASSERT(vmp == heap_lp_arena);
1429 	ASSERT(IS_KMEM_VA_LARGEPAGE(addr));
1430 	ASSERT(((uintptr_t)inaddr & (lpsize - 1)) == 0);
1431 
1432 	for (i = 0; i < nlpages; i++) {
1433 		segkmem_free_one_lp(addr, lpsize);
1434 		addr += lpsize;
1435 	}
1436 
1437 	page_unresv(npages);
1438 
1439 	vmem_free(vmp, inaddr, size);
1440 }
1441 
1442 /*
1443  * This function is called at system boot time by kmem_init right after
1444  * /etc/system file has been read. It checks based on hardware configuration
1445  * and /etc/system settings if system is going to use large pages. The
1446  * initialiazation necessary to actually start using large pages
1447  * happens later in the process after segkmem_heap_lp_init() is called.
1448  */
1449 int
segkmem_lpsetup()1450 segkmem_lpsetup()
1451 {
1452 	int use_large_pages = 0;
1453 
1454 #ifdef __sparc
1455 
1456 	size_t memtotal = physmem * PAGESIZE;
1457 
1458 	if (heap_lp_base == NULL) {
1459 		segkmem_lpsize = PAGESIZE;
1460 		return (0);
1461 	}
1462 
1463 	/* get a platform dependent value of large page size for kernel heap */
1464 	segkmem_lpsize = get_segkmem_lpsize(segkmem_lpsize);
1465 
1466 	if (segkmem_lpsize <= PAGESIZE) {
1467 		/*
1468 		 * put virtual space reserved for the large page kernel
1469 		 * back to the regular heap
1470 		 */
1471 		vmem_xfree(heap_arena, heap_lp_base,
1472 		    heap_lp_end - heap_lp_base);
1473 		heap_lp_base = NULL;
1474 		heap_lp_end = NULL;
1475 		segkmem_lpsize = PAGESIZE;
1476 		return (0);
1477 	}
1478 
1479 	/* set heap_lp quantum if necessary */
1480 	if (segkmem_heaplp_quantum == 0 || !ISP2(segkmem_heaplp_quantum) ||
1481 	    P2PHASE(segkmem_heaplp_quantum, segkmem_lpsize)) {
1482 		segkmem_heaplp_quantum = segkmem_lpsize;
1483 	}
1484 
1485 	/* set kmem_lp quantum if necessary */
1486 	if (segkmem_kmemlp_quantum == 0 || !ISP2(segkmem_kmemlp_quantum) ||
1487 	    segkmem_kmemlp_quantum > segkmem_heaplp_quantum) {
1488 		segkmem_kmemlp_quantum = segkmem_heaplp_quantum;
1489 	}
1490 
1491 	/* set total amount of memory allowed for large page kernel heap */
1492 	if (segkmem_kmemlp_max == 0) {
1493 		if (segkmem_kmemlp_pcnt == 0 || segkmem_kmemlp_pcnt > 100)
1494 			segkmem_kmemlp_pcnt = 12;
1495 		segkmem_kmemlp_max = (memtotal * segkmem_kmemlp_pcnt) / 100;
1496 	}
1497 	segkmem_kmemlp_max = P2ROUNDUP(segkmem_kmemlp_max,
1498 	    segkmem_heaplp_quantum);
1499 
1500 	/* fix lp kmem preallocation request if necesssary */
1501 	if (segkmem_kmemlp_min) {
1502 		segkmem_kmemlp_min = P2ROUNDUP(segkmem_kmemlp_min,
1503 		    segkmem_heaplp_quantum);
1504 		if (segkmem_kmemlp_min > segkmem_kmemlp_max)
1505 			segkmem_kmemlp_min = segkmem_kmemlp_max;
1506 	}
1507 
1508 	use_large_pages = 1;
1509 	segkmem_lpszc = page_szc(segkmem_lpsize);
1510 	segkmem_lpshift = page_get_shift(segkmem_lpszc);
1511 
1512 #endif
1513 	return (use_large_pages);
1514 }
1515 
1516 void
segkmem_zio_init(void * zio_mem_base,size_t zio_mem_size)1517 segkmem_zio_init(void *zio_mem_base, size_t zio_mem_size)
1518 {
1519 	ASSERT(zio_mem_base != NULL);
1520 	ASSERT(zio_mem_size != 0);
1521 
1522 	/*
1523 	 * To reduce VA space fragmentation, we set up quantum caches for the
1524 	 * smaller sizes;  we chose 32k because that translates to 128k VA
1525 	 * slabs, which matches nicely with the common 128k zio_data bufs.
1526 	 */
1527 	zio_arena = vmem_create("zfs_file_data", zio_mem_base, zio_mem_size,
1528 	    PAGESIZE, NULL, NULL, NULL, 32 * 1024, VM_SLEEP);
1529 
1530 	zio_alloc_arena = vmem_create("zfs_file_data_buf", NULL, 0, PAGESIZE,
1531 	    segkmem_zio_alloc, segkmem_zio_free, zio_arena, 0, VM_SLEEP);
1532 
1533 	ASSERT(zio_arena != NULL);
1534 	ASSERT(zio_alloc_arena != NULL);
1535 }
1536 
1537 #ifdef __sparc
1538 
1539 
1540 static void *
segkmem_alloc_ppa(vmem_t * vmp,size_t size,int vmflag)1541 segkmem_alloc_ppa(vmem_t *vmp, size_t size, int vmflag)
1542 {
1543 	size_t ppaquantum = btopr(segkmem_lpsize) * sizeof (page_t *);
1544 	void   *addr;
1545 
1546 	if (ppaquantum <= PAGESIZE)
1547 		return (segkmem_alloc(vmp, size, vmflag));
1548 
1549 	ASSERT((size & (ppaquantum - 1)) == 0);
1550 
1551 	addr = vmem_xalloc(vmp, size, ppaquantum, 0, 0, NULL, NULL, vmflag);
1552 	if (addr != NULL && segkmem_xalloc(vmp, addr, size, vmflag, 0,
1553 	    segkmem_page_create, NULL) == NULL) {
1554 		vmem_xfree(vmp, addr, size);
1555 		addr = NULL;
1556 	}
1557 
1558 	return (addr);
1559 }
1560 
1561 static void
segkmem_free_ppa(vmem_t * vmp,void * addr,size_t size)1562 segkmem_free_ppa(vmem_t *vmp, void *addr, size_t size)
1563 {
1564 	size_t ppaquantum = btopr(segkmem_lpsize) * sizeof (page_t *);
1565 
1566 	ASSERT(addr != NULL);
1567 
1568 	if (ppaquantum <= PAGESIZE) {
1569 		segkmem_free(vmp, addr, size);
1570 	} else {
1571 		segkmem_free(NULL, addr, size);
1572 		vmem_xfree(vmp, addr, size);
1573 	}
1574 }
1575 
1576 void
segkmem_heap_lp_init()1577 segkmem_heap_lp_init()
1578 {
1579 	segkmem_lpcb_t *lpcb = &segkmem_lpcb;
1580 	size_t heap_lp_size = heap_lp_end - heap_lp_base;
1581 	size_t lpsize = segkmem_lpsize;
1582 	size_t ppaquantum;
1583 	void   *addr;
1584 
1585 	if (segkmem_lpsize <= PAGESIZE) {
1586 		ASSERT(heap_lp_base == NULL);
1587 		ASSERT(heap_lp_end == NULL);
1588 		return;
1589 	}
1590 
1591 	ASSERT(segkmem_heaplp_quantum >= lpsize);
1592 	ASSERT((segkmem_heaplp_quantum & (lpsize - 1)) == 0);
1593 	ASSERT(lpcb->lp_uselp == 0);
1594 	ASSERT(heap_lp_base != NULL);
1595 	ASSERT(heap_lp_end != NULL);
1596 	ASSERT(heap_lp_base < heap_lp_end);
1597 	ASSERT(heap_lp_arena == NULL);
1598 	ASSERT(((uintptr_t)heap_lp_base & (lpsize - 1)) == 0);
1599 	ASSERT(((uintptr_t)heap_lp_end & (lpsize - 1)) == 0);
1600 
1601 	/* create large page heap arena */
1602 	heap_lp_arena = vmem_create("heap_lp", heap_lp_base, heap_lp_size,
1603 	    segkmem_heaplp_quantum, NULL, NULL, NULL, 0, VM_SLEEP);
1604 
1605 	ASSERT(heap_lp_arena != NULL);
1606 
1607 	/* This arena caches memory already mapped by large pages */
1608 	kmem_lp_arena = vmem_create("kmem_lp", NULL, 0, segkmem_kmemlp_quantum,
1609 	    segkmem_alloc_lpi, segkmem_free_lpi, heap_lp_arena, 0, VM_SLEEP);
1610 
1611 	ASSERT(kmem_lp_arena != NULL);
1612 
1613 	mutex_init(&lpcb->lp_lock, NULL, MUTEX_DEFAULT, NULL);
1614 	cv_init(&lpcb->lp_cv, NULL, CV_DEFAULT, NULL);
1615 
1616 	/*
1617 	 * this arena is used for the array of page_t pointers necessary
1618 	 * to call hat_mem_load_array
1619 	 */
1620 	ppaquantum = btopr(lpsize) * sizeof (page_t *);
1621 	segkmem_ppa_arena = vmem_create("segkmem_ppa", NULL, 0, ppaquantum,
1622 	    segkmem_alloc_ppa, segkmem_free_ppa, heap_arena, ppaquantum,
1623 	    VM_SLEEP);
1624 
1625 	ASSERT(segkmem_ppa_arena != NULL);
1626 
1627 	/* prealloacate some memory for the lp kernel heap */
1628 	if (segkmem_kmemlp_min) {
1629 
1630 		ASSERT(P2PHASE(segkmem_kmemlp_min,
1631 		    segkmem_heaplp_quantum) == 0);
1632 
1633 		if ((addr = segkmem_alloc_lpi(heap_lp_arena,
1634 		    segkmem_kmemlp_min, VM_SLEEP)) != NULL) {
1635 
1636 			addr = vmem_add(kmem_lp_arena, addr,
1637 			    segkmem_kmemlp_min, VM_SLEEP);
1638 			ASSERT(addr != NULL);
1639 		}
1640 	}
1641 
1642 	lpcb->lp_uselp = 1;
1643 }
1644 
1645 #endif
1646