xref: /freebsd/sys/dev/md/md.c (revision 15925062e1ba75cb4908a68655b797870187ea57)
1 /*-
2  * SPDX-License-Identifier: (Beerware AND BSD-3-Clause)
3  *
4  * ----------------------------------------------------------------------------
5  * "THE BEER-WARE LICENSE" (Revision 42):
6  * <phk@FreeBSD.ORG> wrote this file.  As long as you retain this notice you
7  * can do whatever you want with this stuff. If we meet some day, and you think
8  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
9  * ----------------------------------------------------------------------------
10  *
11  */
12 
13 /*-
14  * The following functions are based on the historical vn(4) driver:
15  * mdstart_swap(), mdstart_vnode(), mdcreate_swap(), mdcreate_vnode()
16  * and mddestroy(), and as such under the following copyright:
17  *
18  * Copyright (c) 1988 University of Utah.
19  * Copyright (c) 1990, 1993
20  *	The Regents of the University of California.  All rights reserved.
21  * Copyright (c) 2013 The FreeBSD Foundation
22  * All rights reserved.
23  *
24  * This code is derived from software contributed to Berkeley by
25  * the Systems Programming Group of the University of Utah Computer
26  * Science Department.
27  *
28  * Portions of this software were developed by Konstantin Belousov
29  * under sponsorship from the FreeBSD Foundation.
30  *
31  * Redistribution and use in source and binary forms, with or without
32  * modification, are permitted provided that the following conditions
33  * are met:
34  * 1. Redistributions of source code must retain the above copyright
35  *    notice, this list of conditions and the following disclaimer.
36  * 2. Redistributions in binary form must reproduce the above copyright
37  *    notice, this list of conditions and the following disclaimer in the
38  *    documentation and/or other materials provided with the distribution.
39  * 3. Neither the name of the University nor the names of its contributors
40  *    may be used to endorse or promote products derived from this software
41  *    without specific prior written permission.
42  *
43  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53  * SUCH DAMAGE.
54  *
55  * from: Utah Hdr: vn.c 1.13 94/04/02
56  * From: src/sys/dev/vn/vn.c,v 1.122 2000/12/16 16:06:03
57  */
58 
59 #include "opt_rootdevname.h"
60 #include "opt_geom.h"
61 #include "opt_md.h"
62 
63 #include <sys/param.h>
64 #include <sys/systm.h>
65 #include <sys/bio.h>
66 #include <sys/buf.h>
67 #include <sys/conf.h>
68 #include <sys/devicestat.h>
69 #include <sys/fcntl.h>
70 #include <sys/kernel.h>
71 #include <sys/kthread.h>
72 #include <sys/limits.h>
73 #include <sys/linker.h>
74 #include <sys/lock.h>
75 #include <sys/malloc.h>
76 #include <sys/mdioctl.h>
77 #include <sys/mount.h>
78 #include <sys/mutex.h>
79 #include <sys/sx.h>
80 #include <sys/namei.h>
81 #include <sys/proc.h>
82 #include <sys/queue.h>
83 #include <sys/rwlock.h>
84 #include <sys/sbuf.h>
85 #include <sys/sched.h>
86 #include <sys/sf_buf.h>
87 #include <sys/sysctl.h>
88 #include <sys/uio.h>
89 #include <sys/unistd.h>
90 #include <sys/vnode.h>
91 #include <sys/disk.h>
92 #include <sys/param.h>
93 #include <sys/bus.h>
94 
95 #include <geom/geom.h>
96 #include <geom/geom_int.h>
97 
98 #include <vm/vm.h>
99 #include <vm/vm_extern.h>
100 #include <vm/vm_param.h>
101 #include <vm/vm_object.h>
102 #include <vm/vm_page.h>
103 #include <vm/vm_pager.h>
104 #include <vm/swap_pager.h>
105 #include <vm/uma.h>
106 
107 #include <machine/bus.h>
108 
109 #define MD_MODVER 1
110 
111 #define MD_SHUTDOWN	0x10000		/* Tell worker thread to terminate. */
112 #define	MD_EXITING	0x20000		/* Worker thread is exiting. */
113 #define MD_PROVIDERGONE	0x40000		/* Safe to free the softc */
114 
115 #ifndef MD_NSECT
116 #define MD_NSECT (10000 * 2)
117 #endif
118 
119 struct md_req {
120 	unsigned	md_unit;	/* unit number */
121 	enum md_types	md_type;	/* type of disk */
122 	off_t		md_mediasize;	/* size of disk in bytes */
123 	unsigned	md_sectorsize;	/* sectorsize */
124 	unsigned	md_options;	/* options */
125 	int		md_fwheads;	/* firmware heads */
126 	int		md_fwsectors;	/* firmware sectors */
127 	char		*md_file;	/* pathname of file to mount */
128 	enum uio_seg	md_file_seg;	/* location of md_file */
129 	char		*md_label;	/* label of the device (userspace) */
130 	int		*md_units;	/* pointer to units array (kernel) */
131 	size_t		md_units_nitems; /* items in md_units array */
132 };
133 
134 #ifdef COMPAT_FREEBSD32
135 struct md_ioctl32 {
136 	unsigned	md_version;
137 	unsigned	md_unit;
138 	enum md_types	md_type;
139 	uint32_t	md_file;
140 	off_t		md_mediasize;
141 	unsigned	md_sectorsize;
142 	unsigned	md_options;
143 	uint64_t	md_base;
144 	int		md_fwheads;
145 	int		md_fwsectors;
146 	uint32_t	md_label;
147 	int		md_pad[MDNPAD];
148 }
149 #ifdef __amd64__
150 __attribute__((__packed__))
151 #endif
152 ;
153 #ifndef __amd64__
154 CTASSERT((sizeof(struct md_ioctl32)) == 440);
155 #else
156 CTASSERT((sizeof(struct md_ioctl32)) == 436);
157 #endif
158 
159 #define	MDIOCATTACH_32	_IOC_NEWTYPE(MDIOCATTACH, struct md_ioctl32)
160 #define	MDIOCDETACH_32	_IOC_NEWTYPE(MDIOCDETACH, struct md_ioctl32)
161 #define	MDIOCQUERY_32	_IOC_NEWTYPE(MDIOCQUERY, struct md_ioctl32)
162 #define	MDIOCRESIZE_32	_IOC_NEWTYPE(MDIOCRESIZE, struct md_ioctl32)
163 #endif /* COMPAT_FREEBSD32 */
164 
165 static MALLOC_DEFINE(M_MD, "md_disk", "Memory Disk");
166 static MALLOC_DEFINE(M_MDSECT, "md_sectors", "Memory Disk Sectors");
167 
168 static int md_debug;
169 SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0,
170     "Enable md(4) debug messages");
171 static int md_malloc_wait;
172 SYSCTL_INT(_vm, OID_AUTO, md_malloc_wait, CTLFLAG_RW, &md_malloc_wait, 0,
173     "Allow malloc to wait for memory allocations");
174 
175 #if defined(MD_ROOT) && !defined(MD_ROOT_FSTYPE)
176 #define	MD_ROOT_FSTYPE	"ufs"
177 #endif
178 
179 #if defined(MD_ROOT)
180 /*
181  * Preloaded image gets put here.
182  */
183 #if defined(MD_ROOT_SIZE)
184 /*
185  * We put the mfs_root symbol into the oldmfs section of the kernel object file.
186  * Applications that patch the object with the image can determine
187  * the size looking at the oldmfs section size within the kernel.
188  */
189 u_char mfs_root[MD_ROOT_SIZE*1024] __attribute__ ((section ("oldmfs")));
190 const int mfs_root_size = sizeof(mfs_root);
191 #elif defined(MD_ROOT_MEM)
192 /* MD region already mapped in the memory */
193 u_char *mfs_root;
194 int mfs_root_size;
195 #else
196 extern volatile u_char __weak_symbol mfs_root;
197 extern volatile u_char __weak_symbol mfs_root_end;
198 #define mfs_root_size ((uintptr_t)(&mfs_root_end - &mfs_root))
199 #endif
200 #endif
201 
202 static g_init_t g_md_init;
203 static g_fini_t g_md_fini;
204 static g_start_t g_md_start;
205 static g_access_t g_md_access;
206 static void g_md_dumpconf(struct sbuf *sb, const char *indent,
207     struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp);
208 static g_provgone_t g_md_providergone;
209 
210 static struct cdev *status_dev = NULL;
211 static struct sx md_sx;
212 static struct unrhdr *md_uh;
213 
214 static d_ioctl_t mdctlioctl;
215 
216 static struct cdevsw mdctl_cdevsw = {
217 	.d_version =	D_VERSION,
218 	.d_ioctl =	mdctlioctl,
219 	.d_name =	MD_NAME,
220 };
221 
222 struct g_class g_md_class = {
223 	.name = "MD",
224 	.version = G_VERSION,
225 	.init = g_md_init,
226 	.fini = g_md_fini,
227 	.start = g_md_start,
228 	.access = g_md_access,
229 	.dumpconf = g_md_dumpconf,
230 	.providergone = g_md_providergone,
231 };
232 
233 DECLARE_GEOM_CLASS(g_md_class, g_md);
234 MODULE_VERSION(geom_md, 0);
235 
236 static LIST_HEAD(, md_s) md_softc_list = LIST_HEAD_INITIALIZER(md_softc_list);
237 
238 #define NINDIR	(PAGE_SIZE / sizeof(uintptr_t))
239 #define NMASK	(NINDIR-1)
240 static int nshift;
241 
242 struct indir {
243 	uintptr_t	*array;
244 	u_int		total;
245 	u_int		used;
246 	u_int		shift;
247 };
248 
249 struct md_s {
250 	int unit;
251 	LIST_ENTRY(md_s) list;
252 	struct bio_queue_head bio_queue;
253 	struct mtx queue_mtx;
254 	struct cdev *dev;
255 	enum md_types type;
256 	off_t mediasize;
257 	unsigned sectorsize;
258 	unsigned opencount;
259 	unsigned fwheads;
260 	unsigned fwsectors;
261 	char ident[DISK_IDENT_SIZE];
262 	unsigned flags;
263 	char name[20];
264 	struct proc *procp;
265 	struct g_geom *gp;
266 	struct g_provider *pp;
267 	int (*start)(struct md_s *sc, struct bio *bp);
268 	struct devstat *devstat;
269 	struct ucred *cred;
270 	char label[PATH_MAX];
271 	bool candelete;
272 
273 	union {
274 		/* MD_MALLOC related fields */
275 		struct {
276 			struct indir *indir;
277 			uma_zone_t uma;
278 		} s_malloc;
279 
280 		/* MD_PRELOAD related fields */
281 		struct {
282 			u_char *pl_ptr;
283 			size_t pl_len;
284 			char name[PATH_MAX];
285 		} s_preload;
286 
287 		/* MD_VNODE related fields */
288 		struct {
289 			struct vnode *vnode;
290 			char file[PATH_MAX];
291 			vm_offset_t kva;
292 		} s_vnode;
293 
294 		/* MD_SWAP related fields */
295 		struct {
296 			vm_object_t object;
297 		} s_swap;
298 
299 		/* MD_NULL */
300 		struct {
301 		} s_null;
302 	};
303 };
304 
305 static struct indir *
new_indir(u_int shift)306 new_indir(u_int shift)
307 {
308 	struct indir *ip;
309 
310 	ip = malloc(sizeof *ip, M_MD, (md_malloc_wait ? M_WAITOK : M_NOWAIT)
311 	    | M_ZERO);
312 	if (ip == NULL)
313 		return (NULL);
314 	ip->array = malloc(sizeof(uintptr_t) * NINDIR,
315 	    M_MDSECT, (md_malloc_wait ? M_WAITOK : M_NOWAIT) | M_ZERO);
316 	if (ip->array == NULL) {
317 		free(ip, M_MD);
318 		return (NULL);
319 	}
320 	ip->total = NINDIR;
321 	ip->shift = shift;
322 	return (ip);
323 }
324 
325 static void
del_indir(struct indir * ip)326 del_indir(struct indir *ip)
327 {
328 
329 	free(ip->array, M_MDSECT);
330 	free(ip, M_MD);
331 }
332 
333 static void
destroy_indir(struct md_s * sc,struct indir * ip)334 destroy_indir(struct md_s *sc, struct indir *ip)
335 {
336 	int i;
337 
338 	for (i = 0; i < NINDIR; i++) {
339 		if (!ip->array[i])
340 			continue;
341 		if (ip->shift)
342 			destroy_indir(sc, (struct indir*)(ip->array[i]));
343 		else if (ip->array[i] > 255)
344 			uma_zfree(sc->s_malloc.uma, (void *)(ip->array[i]));
345 	}
346 	del_indir(ip);
347 }
348 
349 /*
350  * This function does the math and allocates the top level "indir" structure
351  * for a device of "size" sectors.
352  */
353 
354 static struct indir *
dimension(off_t size)355 dimension(off_t size)
356 {
357 	off_t rcnt;
358 	struct indir *ip;
359 	int layer;
360 
361 	rcnt = size;
362 	layer = 0;
363 	while (rcnt > NINDIR) {
364 		rcnt /= NINDIR;
365 		layer++;
366 	}
367 
368 	/*
369 	 * XXX: the top layer is probably not fully populated, so we allocate
370 	 * too much space for ip->array in here.
371 	 */
372 	ip = malloc(sizeof *ip, M_MD, M_WAITOK | M_ZERO);
373 	ip->array = malloc(sizeof(uintptr_t) * NINDIR,
374 	    M_MDSECT, M_WAITOK | M_ZERO);
375 	ip->total = NINDIR;
376 	ip->shift = layer * nshift;
377 	return (ip);
378 }
379 
380 /*
381  * Read a given sector
382  */
383 
384 static uintptr_t
s_read(struct indir * ip,off_t offset)385 s_read(struct indir *ip, off_t offset)
386 {
387 	struct indir *cip;
388 	int idx;
389 	uintptr_t up;
390 
391 	if (md_debug > 1)
392 		printf("s_read(%jd)\n", (intmax_t)offset);
393 	up = 0;
394 	for (cip = ip; cip != NULL;) {
395 		if (cip->shift) {
396 			idx = (offset >> cip->shift) & NMASK;
397 			up = cip->array[idx];
398 			cip = (struct indir *)up;
399 			continue;
400 		}
401 		idx = offset & NMASK;
402 		return (cip->array[idx]);
403 	}
404 	return (0);
405 }
406 
407 /*
408  * Write a given sector, prune the tree if the value is 0
409  */
410 
411 static int
s_write(struct indir * ip,off_t offset,uintptr_t ptr)412 s_write(struct indir *ip, off_t offset, uintptr_t ptr)
413 {
414 	struct indir *cip, *lip[10];
415 	int idx, li;
416 	uintptr_t up;
417 
418 	if (md_debug > 1)
419 		printf("s_write(%jd, %p)\n", (intmax_t)offset, (void *)ptr);
420 	up = 0;
421 	li = 0;
422 	cip = ip;
423 	for (;;) {
424 		lip[li++] = cip;
425 		if (cip->shift) {
426 			idx = (offset >> cip->shift) & NMASK;
427 			up = cip->array[idx];
428 			if (up != 0) {
429 				cip = (struct indir *)up;
430 				continue;
431 			}
432 			/* Allocate branch */
433 			cip->array[idx] =
434 			    (uintptr_t)new_indir(cip->shift - nshift);
435 			if (cip->array[idx] == 0)
436 				return (ENOSPC);
437 			cip->used++;
438 			up = cip->array[idx];
439 			cip = (struct indir *)up;
440 			continue;
441 		}
442 		/* leafnode */
443 		idx = offset & NMASK;
444 		up = cip->array[idx];
445 		if (up != 0)
446 			cip->used--;
447 		cip->array[idx] = ptr;
448 		if (ptr != 0)
449 			cip->used++;
450 		break;
451 	}
452 	if (cip->used != 0 || li == 1)
453 		return (0);
454 	li--;
455 	while (cip->used == 0 && cip != ip) {
456 		li--;
457 		idx = (offset >> lip[li]->shift) & NMASK;
458 		up = lip[li]->array[idx];
459 		KASSERT(up == (uintptr_t)cip, ("md screwed up"));
460 		del_indir(cip);
461 		lip[li]->array[idx] = 0;
462 		lip[li]->used--;
463 		cip = lip[li];
464 	}
465 	return (0);
466 }
467 
468 static int
g_md_access(struct g_provider * pp,int r,int w,int e)469 g_md_access(struct g_provider *pp, int r, int w, int e)
470 {
471 	struct md_s *sc;
472 
473 	sc = pp->geom->softc;
474 	if (sc == NULL) {
475 		if (r <= 0 && w <= 0 && e <= 0)
476 			return (0);
477 		return (ENXIO);
478 	}
479 	r += pp->acr;
480 	w += pp->acw;
481 	e += pp->ace;
482 	if ((sc->flags & MD_READONLY) != 0 && w > 0)
483 		return (EROFS);
484 	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
485 		sc->opencount = 1;
486 	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
487 		sc->opencount = 0;
488 	}
489 	return (0);
490 }
491 
492 static void
g_md_start(struct bio * bp)493 g_md_start(struct bio *bp)
494 {
495 	struct md_s *sc;
496 
497 	sc = bp->bio_to->geom->softc;
498 	if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE)) {
499 		devstat_start_transaction_bio(sc->devstat, bp);
500 	}
501 	mtx_lock(&sc->queue_mtx);
502 	bioq_disksort(&sc->bio_queue, bp);
503 	wakeup(sc);
504 	mtx_unlock(&sc->queue_mtx);
505 }
506 
507 #define	MD_MALLOC_MOVE_ZERO	1
508 #define	MD_MALLOC_MOVE_FILL	2
509 #define	MD_MALLOC_MOVE_READ	3
510 #define	MD_MALLOC_MOVE_WRITE	4
511 #define	MD_MALLOC_MOVE_CMP	5
512 
513 static int
md_malloc_move_ma(vm_page_t ** mp,int * ma_offs,unsigned sectorsize,void * ptr,u_char fill,int op)514 md_malloc_move_ma(vm_page_t **mp, int *ma_offs, unsigned sectorsize,
515     void *ptr, u_char fill, int op)
516 {
517 	struct sf_buf *sf;
518 	vm_page_t m, *mp1;
519 	char *p, first;
520 	off_t *uc;
521 	unsigned n;
522 	int error, i, ma_offs1, sz, first_read;
523 
524 	m = NULL;
525 	error = 0;
526 	sf = NULL;
527 	/* if (op == MD_MALLOC_MOVE_CMP) { gcc */
528 		first = 0;
529 		first_read = 0;
530 		uc = ptr;
531 		mp1 = *mp;
532 		ma_offs1 = *ma_offs;
533 	/* } */
534 	sched_pin();
535 	for (n = sectorsize; n != 0; n -= sz) {
536 		sz = imin(PAGE_SIZE - *ma_offs, n);
537 		if (m != **mp) {
538 			if (sf != NULL)
539 				sf_buf_free(sf);
540 			m = **mp;
541 			sf = sf_buf_alloc(m, SFB_CPUPRIVATE |
542 			    (md_malloc_wait ? 0 : SFB_NOWAIT));
543 			if (sf == NULL) {
544 				error = ENOMEM;
545 				break;
546 			}
547 		}
548 		p = (char *)sf_buf_kva(sf) + *ma_offs;
549 		switch (op) {
550 		case MD_MALLOC_MOVE_ZERO:
551 			bzero(p, sz);
552 			break;
553 		case MD_MALLOC_MOVE_FILL:
554 			memset(p, fill, sz);
555 			break;
556 		case MD_MALLOC_MOVE_READ:
557 			bcopy(ptr, p, sz);
558 			cpu_flush_dcache(p, sz);
559 			break;
560 		case MD_MALLOC_MOVE_WRITE:
561 			bcopy(p, ptr, sz);
562 			break;
563 		case MD_MALLOC_MOVE_CMP:
564 			for (i = 0; i < sz; i++, p++) {
565 				if (!first_read) {
566 					*uc = (u_char)*p;
567 					first = *p;
568 					first_read = 1;
569 				} else if (*p != first) {
570 					error = EDOOFUS;
571 					break;
572 				}
573 			}
574 			break;
575 		default:
576 			KASSERT(0, ("md_malloc_move_ma unknown op %d\n", op));
577 			break;
578 		}
579 		if (error != 0)
580 			break;
581 		*ma_offs += sz;
582 		*ma_offs %= PAGE_SIZE;
583 		if (*ma_offs == 0)
584 			(*mp)++;
585 		ptr = (char *)ptr + sz;
586 	}
587 
588 	if (sf != NULL)
589 		sf_buf_free(sf);
590 	sched_unpin();
591 	if (op == MD_MALLOC_MOVE_CMP && error != 0) {
592 		*mp = mp1;
593 		*ma_offs = ma_offs1;
594 	}
595 	return (error);
596 }
597 
598 static int
md_malloc_move_vlist(bus_dma_segment_t ** pvlist,int * pma_offs,unsigned len,void * ptr,u_char fill,int op)599 md_malloc_move_vlist(bus_dma_segment_t **pvlist, int *pma_offs,
600     unsigned len, void *ptr, u_char fill, int op)
601 {
602 	bus_dma_segment_t *vlist;
603 	uint8_t *p, *end, first;
604 	off_t *uc;
605 	int ma_offs, seg_len;
606 
607 	vlist = *pvlist;
608 	ma_offs = *pma_offs;
609 	uc = ptr;
610 
611 	for (; len != 0; len -= seg_len) {
612 		seg_len = imin(vlist->ds_len - ma_offs, len);
613 		p = (uint8_t *)(uintptr_t)vlist->ds_addr + ma_offs;
614 		switch (op) {
615 		case MD_MALLOC_MOVE_ZERO:
616 			bzero(p, seg_len);
617 			break;
618 		case MD_MALLOC_MOVE_FILL:
619 			memset(p, fill, seg_len);
620 			break;
621 		case MD_MALLOC_MOVE_READ:
622 			bcopy(ptr, p, seg_len);
623 			cpu_flush_dcache(p, seg_len);
624 			break;
625 		case MD_MALLOC_MOVE_WRITE:
626 			bcopy(p, ptr, seg_len);
627 			break;
628 		case MD_MALLOC_MOVE_CMP:
629 			end = p + seg_len;
630 			first = *uc = *p;
631 			/* Confirm all following bytes match the first */
632 			while (++p < end) {
633 				if (*p != first)
634 					return (EDOOFUS);
635 			}
636 			break;
637 		default:
638 			KASSERT(0, ("md_malloc_move_vlist unknown op %d\n", op));
639 			break;
640 		}
641 
642 		ma_offs += seg_len;
643 		if (ma_offs == vlist->ds_len) {
644 			ma_offs = 0;
645 			vlist++;
646 		}
647 		ptr = (uint8_t *)ptr + seg_len;
648 	}
649 	*pvlist = vlist;
650 	*pma_offs = ma_offs;
651 
652 	return (0);
653 }
654 
655 static int
mdstart_malloc(struct md_s * sc,struct bio * bp)656 mdstart_malloc(struct md_s *sc, struct bio *bp)
657 {
658 	u_char *dst;
659 	vm_page_t *m;
660 	bus_dma_segment_t *vlist;
661 	int i, error, error1, ma_offs, notmapped;
662 	off_t secno, nsec, uc;
663 	uintptr_t sp, osp;
664 
665 	switch (bp->bio_cmd) {
666 	case BIO_READ:
667 	case BIO_WRITE:
668 	case BIO_DELETE:
669 		break;
670 	case BIO_FLUSH:
671 		return (0);
672 	default:
673 		return (EOPNOTSUPP);
674 	}
675 
676 	notmapped = (bp->bio_flags & BIO_UNMAPPED) != 0;
677 	vlist = (bp->bio_flags & BIO_VLIST) != 0 ?
678 	    (bus_dma_segment_t *)bp->bio_data : NULL;
679 	if (notmapped) {
680 		m = bp->bio_ma;
681 		ma_offs = bp->bio_ma_offset;
682 		dst = NULL;
683 		KASSERT(vlist == NULL, ("vlists cannot be unmapped"));
684 	} else if (vlist != NULL) {
685 		ma_offs = bp->bio_ma_offset;
686 		dst = NULL;
687 	} else {
688 		dst = bp->bio_data;
689 	}
690 
691 	nsec = bp->bio_length / sc->sectorsize;
692 	secno = bp->bio_offset / sc->sectorsize;
693 	error = 0;
694 	while (nsec--) {
695 		osp = s_read(sc->s_malloc.indir, secno);
696 		if (bp->bio_cmd == BIO_DELETE) {
697 			if (osp != 0)
698 				error = s_write(sc->s_malloc.indir, secno, 0);
699 		} else if (bp->bio_cmd == BIO_READ) {
700 			if (osp == 0) {
701 				if (notmapped) {
702 					error = md_malloc_move_ma(&m, &ma_offs,
703 					    sc->sectorsize, NULL, 0,
704 					    MD_MALLOC_MOVE_ZERO);
705 				} else if (vlist != NULL) {
706 					error = md_malloc_move_vlist(&vlist,
707 					    &ma_offs, sc->sectorsize, NULL, 0,
708 					    MD_MALLOC_MOVE_ZERO);
709 				} else
710 					bzero(dst, sc->sectorsize);
711 			} else if (osp <= 255) {
712 				if (notmapped) {
713 					error = md_malloc_move_ma(&m, &ma_offs,
714 					    sc->sectorsize, NULL, osp,
715 					    MD_MALLOC_MOVE_FILL);
716 				} else if (vlist != NULL) {
717 					error = md_malloc_move_vlist(&vlist,
718 					    &ma_offs, sc->sectorsize, NULL, osp,
719 					    MD_MALLOC_MOVE_FILL);
720 				} else
721 					memset(dst, osp, sc->sectorsize);
722 			} else {
723 				if (notmapped) {
724 					error = md_malloc_move_ma(&m, &ma_offs,
725 					    sc->sectorsize, (void *)osp, 0,
726 					    MD_MALLOC_MOVE_READ);
727 				} else if (vlist != NULL) {
728 					error = md_malloc_move_vlist(&vlist,
729 					    &ma_offs, sc->sectorsize,
730 					    (void *)osp, 0,
731 					    MD_MALLOC_MOVE_READ);
732 				} else {
733 					bcopy((void *)osp, dst, sc->sectorsize);
734 					cpu_flush_dcache(dst, sc->sectorsize);
735 				}
736 			}
737 			osp = 0;
738 		} else if (bp->bio_cmd == BIO_WRITE) {
739 			if (sc->flags & MD_COMPRESS) {
740 				if (notmapped) {
741 					error1 = md_malloc_move_ma(&m, &ma_offs,
742 					    sc->sectorsize, &uc, 0,
743 					    MD_MALLOC_MOVE_CMP);
744 					i = error1 == 0 ? sc->sectorsize : 0;
745 				} else if (vlist != NULL) {
746 					error1 = md_malloc_move_vlist(&vlist,
747 					    &ma_offs, sc->sectorsize, &uc, 0,
748 					    MD_MALLOC_MOVE_CMP);
749 					i = error1 == 0 ? sc->sectorsize : 0;
750 				} else {
751 					uc = dst[0];
752 					for (i = 1; i < sc->sectorsize; i++) {
753 						if (dst[i] != uc)
754 							break;
755 					}
756 				}
757 			} else {
758 				i = 0;
759 				uc = 0;
760 			}
761 			if (i == sc->sectorsize) {
762 				if (osp != uc)
763 					error = s_write(sc->s_malloc.indir,
764 					    secno, uc);
765 			} else {
766 				if (osp <= 255) {
767 					sp = (uintptr_t)uma_zalloc(
768 					    sc->s_malloc.uma,
769 					    md_malloc_wait ? M_WAITOK :
770 					    M_NOWAIT);
771 					if (sp == 0) {
772 						error = ENOSPC;
773 						break;
774 					}
775 					if (notmapped) {
776 						error = md_malloc_move_ma(&m,
777 						    &ma_offs, sc->sectorsize,
778 						    (void *)sp, 0,
779 						    MD_MALLOC_MOVE_WRITE);
780 					} else if (vlist != NULL) {
781 						error = md_malloc_move_vlist(
782 						    &vlist, &ma_offs,
783 						    sc->sectorsize, (void *)sp,
784 						    0, MD_MALLOC_MOVE_WRITE);
785 					} else {
786 						bcopy(dst, (void *)sp,
787 						    sc->sectorsize);
788 					}
789 					error = s_write(sc->s_malloc.indir,
790 					    secno, sp);
791 				} else {
792 					if (notmapped) {
793 						error = md_malloc_move_ma(&m,
794 						    &ma_offs, sc->sectorsize,
795 						    (void *)osp, 0,
796 						    MD_MALLOC_MOVE_WRITE);
797 					} else if (vlist != NULL) {
798 						error = md_malloc_move_vlist(
799 						    &vlist, &ma_offs,
800 						    sc->sectorsize, (void *)osp,
801 						    0, MD_MALLOC_MOVE_WRITE);
802 					} else {
803 						bcopy(dst, (void *)osp,
804 						    sc->sectorsize);
805 					}
806 					osp = 0;
807 				}
808 			}
809 		} else {
810 			error = EOPNOTSUPP;
811 		}
812 		if (osp > 255)
813 			uma_zfree(sc->s_malloc.uma, (void*)osp);
814 		if (error != 0)
815 			break;
816 		secno++;
817 		if (!notmapped && vlist == NULL)
818 			dst += sc->sectorsize;
819 	}
820 	bp->bio_resid = 0;
821 	return (error);
822 }
823 
824 static void
mdcopyto_vlist(void * src,bus_dma_segment_t * vlist,off_t offset,off_t len)825 mdcopyto_vlist(void *src, bus_dma_segment_t *vlist, off_t offset, off_t len)
826 {
827 	off_t seg_len;
828 
829 	while (offset >= vlist->ds_len) {
830 		offset -= vlist->ds_len;
831 		vlist++;
832 	}
833 
834 	while (len != 0) {
835 		seg_len = omin(len, vlist->ds_len - offset);
836 		bcopy(src, (void *)(uintptr_t)(vlist->ds_addr + offset),
837 		    seg_len);
838 		offset = 0;
839 		src = (uint8_t *)src + seg_len;
840 		len -= seg_len;
841 		vlist++;
842 	}
843 }
844 
845 static void
mdcopyfrom_vlist(bus_dma_segment_t * vlist,off_t offset,void * dst,off_t len)846 mdcopyfrom_vlist(bus_dma_segment_t *vlist, off_t offset, void *dst, off_t len)
847 {
848 	off_t seg_len;
849 
850 	while (offset >= vlist->ds_len) {
851 		offset -= vlist->ds_len;
852 		vlist++;
853 	}
854 
855 	while (len != 0) {
856 		seg_len = omin(len, vlist->ds_len - offset);
857 		bcopy((void *)(uintptr_t)(vlist->ds_addr + offset), dst,
858 		    seg_len);
859 		offset = 0;
860 		dst = (uint8_t *)dst + seg_len;
861 		len -= seg_len;
862 		vlist++;
863 	}
864 }
865 
866 static int
mdstart_preload(struct md_s * sc,struct bio * bp)867 mdstart_preload(struct md_s *sc, struct bio *bp)
868 {
869 	uint8_t *p;
870 
871 	p = sc->s_preload.pl_ptr + bp->bio_offset;
872 	switch (bp->bio_cmd) {
873 	case BIO_READ:
874 		if ((bp->bio_flags & BIO_VLIST) != 0) {
875 			mdcopyto_vlist(p, (bus_dma_segment_t *)bp->bio_data,
876 			    bp->bio_ma_offset, bp->bio_length);
877 		} else {
878 			bcopy(p, bp->bio_data, bp->bio_length);
879 		}
880 		cpu_flush_dcache(bp->bio_data, bp->bio_length);
881 		break;
882 	case BIO_WRITE:
883 		if ((bp->bio_flags & BIO_VLIST) != 0) {
884 			mdcopyfrom_vlist((bus_dma_segment_t *)bp->bio_data,
885 			    bp->bio_ma_offset, p, bp->bio_length);
886 		} else {
887 			bcopy(bp->bio_data, p, bp->bio_length);
888 		}
889 		break;
890 	}
891 	bp->bio_resid = 0;
892 	return (0);
893 }
894 
895 static int
mdstart_vnode(struct md_s * sc,struct bio * bp)896 mdstart_vnode(struct md_s *sc, struct bio *bp)
897 {
898 	int error;
899 	struct uio auio;
900 	struct iovec aiov;
901 	struct iovec *piov;
902 	struct mount *mp;
903 	struct vnode *vp;
904 	bus_dma_segment_t *vlist;
905 	struct thread *td;
906 	off_t iolen, iostart, off, len;
907 	int ma_offs, npages;
908 	bool mapped;
909 
910 	td = curthread;
911 	vp = sc->s_vnode.vnode;
912 	piov = NULL;
913 	ma_offs = bp->bio_ma_offset;
914 	off = bp->bio_offset;
915 	len = bp->bio_length;
916 	mapped = false;
917 
918 	/*
919 	 * VNODE I/O
920 	 *
921 	 * If an error occurs, we set BIO_ERROR but we do not set
922 	 * B_INVAL because (for a write anyway), the buffer is
923 	 * still valid.
924 	 */
925 
926 	switch (bp->bio_cmd) {
927 	case BIO_READ:
928 		auio.uio_rw = UIO_READ;
929 		break;
930 	case BIO_WRITE:
931 		auio.uio_rw = UIO_WRITE;
932 		break;
933 	case BIO_FLUSH:
934 		do {
935 			(void)vn_start_write(vp, &mp, V_WAIT);
936 			vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
937 			error = VOP_FSYNC(vp, MNT_WAIT, td);
938 			VOP_UNLOCK(vp);
939 			vn_finished_write(mp);
940 		} while (error == ERELOOKUP);
941 		return (error);
942 	case BIO_DELETE:
943 		if (sc->candelete) {
944 			error = vn_deallocate(vp, &off, &len, 0,
945 			    sc->flags & MD_ASYNC ? 0 : IO_SYNC,
946 			    sc->cred, NOCRED);
947 			bp->bio_resid = len;
948 			return (error);
949 		}
950 		/* FALLTHROUGH */
951 	default:
952 		return (EOPNOTSUPP);
953 	}
954 
955 	auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
956 	auio.uio_resid = bp->bio_length;
957 	auio.uio_segflg = UIO_SYSSPACE;
958 	auio.uio_td = td;
959 
960 	if ((bp->bio_flags & BIO_VLIST) != 0) {
961 		piov = malloc(sizeof(*piov) * bp->bio_ma_n, M_MD, M_WAITOK);
962 		auio.uio_iov = piov;
963 		vlist = (bus_dma_segment_t *)bp->bio_data;
964 		while (len > 0) {
965 			piov->iov_base = (void *)(uintptr_t)(vlist->ds_addr +
966 			    ma_offs);
967 			piov->iov_len = vlist->ds_len - ma_offs;
968 			if (piov->iov_len > len)
969 				piov->iov_len = len;
970 			len -= piov->iov_len;
971 			ma_offs = 0;
972 			vlist++;
973 			piov++;
974 		}
975 		auio.uio_iovcnt = piov - auio.uio_iov;
976 		piov = auio.uio_iov;
977 	} else if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
978 		bp->bio_resid = len;
979 unmapped_step:
980 		npages = atop(min(maxphys, round_page(len + (ma_offs &
981 		    PAGE_MASK))));
982 		iolen = min(ptoa(npages) - (ma_offs & PAGE_MASK), len);
983 		KASSERT(iolen > 0, ("zero iolen"));
984 		KASSERT(npages <= atop(maxphys + PAGE_SIZE),
985 		    ("npages %d too large", npages));
986 		pmap_qenter(sc->s_vnode.kva, &bp->bio_ma[atop(ma_offs)],
987 		    npages);
988 		aiov.iov_base = (void *)(sc->s_vnode.kva + (ma_offs &
989 		    PAGE_MASK));
990 		aiov.iov_len = iolen;
991 		auio.uio_iov = &aiov;
992 		auio.uio_iovcnt = 1;
993 		auio.uio_resid = iolen;
994 		mapped = true;
995 	} else {
996 		aiov.iov_base = bp->bio_data;
997 		aiov.iov_len = bp->bio_length;
998 		auio.uio_iov = &aiov;
999 		auio.uio_iovcnt = 1;
1000 	}
1001 	iostart = auio.uio_offset;
1002 	if (bp->bio_cmd == BIO_READ) {
1003 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1004 		error = VOP_READ(vp, &auio, 0, sc->cred);
1005 		VOP_UNLOCK(vp);
1006 	} else {
1007 		(void) vn_start_write(vp, &mp, V_WAIT);
1008 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1009 		error = VOP_WRITE(vp, &auio, sc->flags & MD_ASYNC ? 0 : IO_SYNC,
1010 		    sc->cred);
1011 		VOP_UNLOCK(vp);
1012 		vn_finished_write(mp);
1013 		if (error == 0)
1014 			sc->flags &= ~MD_VERIFY;
1015 	}
1016 
1017 	/* When MD_CACHE is set, try to avoid double-caching the data. */
1018 	if (error == 0 && (sc->flags & MD_CACHE) == 0)
1019 		VOP_ADVISE(vp, iostart, auio.uio_offset - 1,
1020 		    POSIX_FADV_DONTNEED);
1021 
1022 	if (mapped) {
1023 		pmap_qremove(sc->s_vnode.kva, npages);
1024 		if (error == 0) {
1025 			len -= iolen;
1026 			bp->bio_resid -= iolen;
1027 			ma_offs += iolen;
1028 			if (len > 0)
1029 				goto unmapped_step;
1030 		}
1031 	} else {
1032 		bp->bio_resid = auio.uio_resid;
1033 	}
1034 
1035 	free(piov, M_MD);
1036 	return (error);
1037 }
1038 
1039 static int
mdstart_swap(struct md_s * sc,struct bio * bp)1040 mdstart_swap(struct md_s *sc, struct bio *bp)
1041 {
1042 	vm_page_t m;
1043 	u_char *p;
1044 	vm_pindex_t i, lastp;
1045 	bus_dma_segment_t *vlist;
1046 	int rv, ma_offs, offs, len, lastend;
1047 
1048 	switch (bp->bio_cmd) {
1049 	case BIO_READ:
1050 	case BIO_WRITE:
1051 	case BIO_DELETE:
1052 		break;
1053 	case BIO_FLUSH:
1054 		return (0);
1055 	default:
1056 		return (EOPNOTSUPP);
1057 	}
1058 
1059 	p = bp->bio_data;
1060 	ma_offs = (bp->bio_flags & (BIO_UNMAPPED|BIO_VLIST)) != 0 ?
1061 	    bp->bio_ma_offset : 0;
1062 	vlist = (bp->bio_flags & BIO_VLIST) != 0 ?
1063 	    (bus_dma_segment_t *)bp->bio_data : NULL;
1064 
1065 	/*
1066 	 * offs is the offset at which to start operating on the
1067 	 * next (ie, first) page.  lastp is the last page on
1068 	 * which we're going to operate.  lastend is the ending
1069 	 * position within that last page (ie, PAGE_SIZE if
1070 	 * we're operating on complete aligned pages).
1071 	 */
1072 	offs = bp->bio_offset % PAGE_SIZE;
1073 	lastp = (bp->bio_offset + bp->bio_length - 1) / PAGE_SIZE;
1074 	lastend = (bp->bio_offset + bp->bio_length - 1) % PAGE_SIZE + 1;
1075 
1076 	rv = VM_PAGER_OK;
1077 	vm_object_pip_add(sc->s_swap.object, 1);
1078 	for (i = bp->bio_offset / PAGE_SIZE; i <= lastp; i++) {
1079 		len = ((i == lastp) ? lastend : PAGE_SIZE) - offs;
1080 		m = vm_page_grab_unlocked(sc->s_swap.object, i,
1081 		    VM_ALLOC_SYSTEM);
1082 		if (bp->bio_cmd == BIO_READ) {
1083 			if (vm_page_all_valid(m))
1084 				rv = VM_PAGER_OK;
1085 			else
1086 				rv = vm_pager_get_pages(sc->s_swap.object,
1087 				    &m, 1, NULL, NULL);
1088 			if (rv == VM_PAGER_ERROR) {
1089 				VM_OBJECT_WLOCK(sc->s_swap.object);
1090 				vm_page_free(m);
1091 				VM_OBJECT_WUNLOCK(sc->s_swap.object);
1092 				break;
1093 			} else if (rv == VM_PAGER_FAIL) {
1094 				/*
1095 				 * Pager does not have the page.  Zero
1096 				 * the allocated page, and mark it as
1097 				 * valid. Do not set dirty, the page
1098 				 * can be recreated if thrown out.
1099 				 */
1100 				pmap_zero_page(m);
1101 				vm_page_valid(m);
1102 			}
1103 			if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
1104 				pmap_copy_pages(&m, offs, bp->bio_ma,
1105 				    ma_offs, len);
1106 			} else if ((bp->bio_flags & BIO_VLIST) != 0) {
1107 				physcopyout_vlist(VM_PAGE_TO_PHYS(m) + offs,
1108 				    vlist, ma_offs, len);
1109 				cpu_flush_dcache(p, len);
1110 			} else {
1111 				physcopyout(VM_PAGE_TO_PHYS(m) + offs, p, len);
1112 				cpu_flush_dcache(p, len);
1113 			}
1114 		} else if (bp->bio_cmd == BIO_WRITE) {
1115 			if (len == PAGE_SIZE || vm_page_all_valid(m))
1116 				rv = VM_PAGER_OK;
1117 			else
1118 				rv = vm_pager_get_pages(sc->s_swap.object,
1119 				    &m, 1, NULL, NULL);
1120 			if (rv == VM_PAGER_ERROR) {
1121 				VM_OBJECT_WLOCK(sc->s_swap.object);
1122 				vm_page_free(m);
1123 				VM_OBJECT_WUNLOCK(sc->s_swap.object);
1124 				break;
1125 			} else if (rv == VM_PAGER_FAIL)
1126 				pmap_zero_page(m);
1127 
1128 			if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
1129 				pmap_copy_pages(bp->bio_ma, ma_offs, &m,
1130 				    offs, len);
1131 			} else if ((bp->bio_flags & BIO_VLIST) != 0) {
1132 				physcopyin_vlist(vlist, ma_offs,
1133 				    VM_PAGE_TO_PHYS(m) + offs, len);
1134 			} else {
1135 				physcopyin(p, VM_PAGE_TO_PHYS(m) + offs, len);
1136 			}
1137 
1138 			vm_page_valid(m);
1139 			vm_page_set_dirty(m);
1140 		} else if (bp->bio_cmd == BIO_DELETE) {
1141 			if (len == PAGE_SIZE || vm_page_all_valid(m))
1142 				rv = VM_PAGER_OK;
1143 			else
1144 				rv = vm_pager_get_pages(sc->s_swap.object,
1145 				    &m, 1, NULL, NULL);
1146 			VM_OBJECT_WLOCK(sc->s_swap.object);
1147 			if (rv == VM_PAGER_ERROR) {
1148 				vm_page_free(m);
1149 				VM_OBJECT_WUNLOCK(sc->s_swap.object);
1150 				break;
1151 			} else if (rv == VM_PAGER_FAIL) {
1152 				vm_page_free(m);
1153 				m = NULL;
1154 			} else {
1155 				/* Page is valid. */
1156 				if (len != PAGE_SIZE) {
1157 					pmap_zero_page_area(m, offs, len);
1158 					vm_page_set_dirty(m);
1159 				} else {
1160 					vm_pager_page_unswapped(m);
1161 					vm_page_free(m);
1162 					m = NULL;
1163 				}
1164 			}
1165 			VM_OBJECT_WUNLOCK(sc->s_swap.object);
1166 		}
1167 		if (m != NULL) {
1168 			/*
1169 			 * The page may be deactivated prior to setting
1170 			 * PGA_REFERENCED, but in this case it will be
1171 			 * reactivated by the page daemon.
1172 			 */
1173 			if (vm_page_active(m))
1174 				vm_page_reference(m);
1175 			else
1176 				vm_page_activate(m);
1177 			vm_page_xunbusy(m);
1178 		}
1179 
1180 		/* Actions on further pages start at offset 0 */
1181 		p += PAGE_SIZE - offs;
1182 		offs = 0;
1183 		ma_offs += len;
1184 	}
1185 	vm_object_pip_wakeup(sc->s_swap.object);
1186 	return (rv != VM_PAGER_ERROR ? 0 : ENOSPC);
1187 }
1188 
1189 static int
mdstart_null(struct md_s * sc,struct bio * bp)1190 mdstart_null(struct md_s *sc, struct bio *bp)
1191 {
1192 
1193 	switch (bp->bio_cmd) {
1194 	case BIO_READ:
1195 		bzero(bp->bio_data, bp->bio_length);
1196 		cpu_flush_dcache(bp->bio_data, bp->bio_length);
1197 		break;
1198 	case BIO_WRITE:
1199 		break;
1200 	}
1201 	bp->bio_resid = 0;
1202 	return (0);
1203 }
1204 
1205 static void
md_handleattr(struct md_s * sc,struct bio * bp)1206 md_handleattr(struct md_s *sc, struct bio *bp)
1207 {
1208 	if (sc->fwsectors && sc->fwheads &&
1209 	    (g_handleattr_int(bp, "GEOM::fwsectors", sc->fwsectors) != 0 ||
1210 	    g_handleattr_int(bp, "GEOM::fwheads", sc->fwheads) != 0))
1211 		return;
1212 	if (g_handleattr_int(bp, "GEOM::candelete", sc->candelete) != 0)
1213 		return;
1214 	if (sc->ident[0] != '\0' &&
1215 	    g_handleattr_str(bp, "GEOM::ident", sc->ident) != 0)
1216 		return;
1217 	if (g_handleattr_int(bp, "MNT::verified", (sc->flags & MD_VERIFY) != 0))
1218 		return;
1219 	g_io_deliver(bp, EOPNOTSUPP);
1220 }
1221 
1222 static void
md_kthread(void * arg)1223 md_kthread(void *arg)
1224 {
1225 	struct md_s *sc;
1226 	struct bio *bp;
1227 	int error;
1228 
1229 	sc = arg;
1230 	thread_lock(curthread);
1231 	sched_prio(curthread, PRIBIO);
1232 	thread_unlock(curthread);
1233 	if (sc->type == MD_VNODE)
1234 		curthread->td_pflags |= TDP_NORUNNINGBUF;
1235 
1236 	for (;;) {
1237 		mtx_lock(&sc->queue_mtx);
1238 		if (sc->flags & MD_SHUTDOWN) {
1239 			sc->flags |= MD_EXITING;
1240 			mtx_unlock(&sc->queue_mtx);
1241 			kproc_exit(0);
1242 		}
1243 		bp = bioq_takefirst(&sc->bio_queue);
1244 		if (!bp) {
1245 			msleep(sc, &sc->queue_mtx, PRIBIO | PDROP, "mdwait", 0);
1246 			continue;
1247 		}
1248 		mtx_unlock(&sc->queue_mtx);
1249 		if (bp->bio_cmd == BIO_GETATTR) {
1250 			md_handleattr(sc, bp);
1251 		} else {
1252 			error = sc->start(sc, bp);
1253 			if (bp->bio_cmd == BIO_READ || bp->bio_cmd == BIO_WRITE) {
1254 				/*
1255 				 * Devstat uses (bio_bcount, bio_resid) for
1256 				 * determining the length of the completed part
1257 				 * of the i/o.  g_io_deliver() will translate
1258 				 * from bio_completed to that, but it also
1259 				 * destroys the bio so we must do our own
1260 				 * translation.
1261 				 */
1262 				bp->bio_bcount = bp->bio_length;
1263 				devstat_end_transaction_bio(sc->devstat, bp);
1264 			}
1265 			bp->bio_completed = bp->bio_length - bp->bio_resid;
1266 			g_io_deliver(bp, error);
1267 		}
1268 	}
1269 }
1270 
1271 static struct md_s *
mdfind(int unit)1272 mdfind(int unit)
1273 {
1274 	struct md_s *sc;
1275 
1276 	LIST_FOREACH(sc, &md_softc_list, list) {
1277 		if (sc->unit == unit)
1278 			break;
1279 	}
1280 	return (sc);
1281 }
1282 
1283 static struct md_s *
mdnew(int unit,int * errp,enum md_types type)1284 mdnew(int unit, int *errp, enum md_types type)
1285 {
1286 	struct md_s *sc;
1287 	int error;
1288 
1289 	*errp = 0;
1290 	if (unit == -1)
1291 		unit = alloc_unr(md_uh);
1292 	else
1293 		unit = alloc_unr_specific(md_uh, unit);
1294 
1295 	if (unit == -1) {
1296 		*errp = EBUSY;
1297 		return (NULL);
1298 	}
1299 
1300 	sc = malloc(sizeof(*sc), M_MD, M_WAITOK | M_ZERO);
1301 	sc->type = type;
1302 	bioq_init(&sc->bio_queue);
1303 	mtx_init(&sc->queue_mtx, "md bio queue", NULL, MTX_DEF);
1304 	sc->unit = unit;
1305 	sprintf(sc->name, "md%d", unit);
1306 	LIST_INSERT_HEAD(&md_softc_list, sc, list);
1307 	error = kproc_create(md_kthread, sc, &sc->procp, 0, 0,"%s", sc->name);
1308 	if (error == 0)
1309 		return (sc);
1310 	LIST_REMOVE(sc, list);
1311 	mtx_destroy(&sc->queue_mtx);
1312 	free_unr(md_uh, sc->unit);
1313 	free(sc, M_MD);
1314 	*errp = error;
1315 	return (NULL);
1316 }
1317 
1318 static void
mdinit(struct md_s * sc)1319 mdinit(struct md_s *sc)
1320 {
1321 	struct g_geom *gp;
1322 	struct g_provider *pp;
1323 	unsigned remn;
1324 
1325 	g_topology_lock();
1326 	gp = g_new_geomf(&g_md_class, "md%d", sc->unit);
1327 	gp->softc = sc;
1328 	pp = g_new_providerf(gp, "md%d", sc->unit);
1329 	devstat_remove_entry(pp->stat);
1330 	pp->stat = NULL;
1331 	pp->flags |= G_PF_DIRECT_SEND | G_PF_DIRECT_RECEIVE;
1332 	/* Prune off any residual fractional sector. */
1333 	remn = sc->mediasize % sc->sectorsize;
1334 	if (remn != 0) {
1335 		printf("md%d: truncating fractional last sector by %u bytes\n",
1336 		    sc->unit, remn);
1337 		sc->mediasize -= remn;
1338 	}
1339 	pp->mediasize = sc->mediasize;
1340 	pp->sectorsize = sc->sectorsize;
1341 	switch (sc->type) {
1342 	case MD_MALLOC:
1343 	case MD_VNODE:
1344 	case MD_SWAP:
1345 		pp->flags |= G_PF_ACCEPT_UNMAPPED;
1346 		break;
1347 	case MD_PRELOAD:
1348 	case MD_NULL:
1349 		break;
1350 	}
1351 	sc->gp = gp;
1352 	sc->pp = pp;
1353 	sc->devstat = devstat_new_entry("md", sc->unit, sc->sectorsize,
1354 	    DEVSTAT_ALL_SUPPORTED, DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
1355 	sc->devstat->id = pp;
1356 	g_error_provider(pp, 0);
1357 	g_topology_unlock();
1358 }
1359 
1360 static int
mdcreate_malloc(struct md_s * sc,struct md_req * mdr)1361 mdcreate_malloc(struct md_s *sc, struct md_req *mdr)
1362 {
1363 	uintptr_t sp;
1364 	int error;
1365 	off_t u;
1366 
1367 	error = 0;
1368 	if (mdr->md_options & ~(MD_AUTOUNIT | MD_COMPRESS | MD_RESERVE))
1369 		return (EINVAL);
1370 	if (mdr->md_sectorsize != 0 && !powerof2(mdr->md_sectorsize))
1371 		return (EINVAL);
1372 	/* Compression doesn't make sense if we have reserved space */
1373 	if (mdr->md_options & MD_RESERVE)
1374 		mdr->md_options &= ~MD_COMPRESS;
1375 	if (mdr->md_fwsectors != 0)
1376 		sc->fwsectors = mdr->md_fwsectors;
1377 	if (mdr->md_fwheads != 0)
1378 		sc->fwheads = mdr->md_fwheads;
1379 	sc->flags = mdr->md_options & (MD_COMPRESS | MD_FORCE | MD_RESERVE);
1380 	sc->s_malloc.indir = dimension(sc->mediasize / sc->sectorsize);
1381 	sc->s_malloc.uma = uma_zcreate(sc->name, sc->sectorsize, NULL, NULL,
1382 	    NULL, NULL, 0x1ff, 0);
1383 	if (mdr->md_options & MD_RESERVE) {
1384 		off_t nsectors;
1385 
1386 		nsectors = sc->mediasize / sc->sectorsize;
1387 		for (u = 0; u < nsectors; u++) {
1388 			sp = (uintptr_t)uma_zalloc(sc->s_malloc.uma,
1389 			    (md_malloc_wait ? M_WAITOK : M_NOWAIT) | M_ZERO);
1390 			if (sp != 0)
1391 				error = s_write(sc->s_malloc.indir, u, sp);
1392 			else
1393 				error = ENOMEM;
1394 			if (error != 0)
1395 				break;
1396 		}
1397 	}
1398 	return (error);
1399 }
1400 
1401 static int
mdsetcred(struct md_s * sc,struct ucred * cred)1402 mdsetcred(struct md_s *sc, struct ucred *cred)
1403 {
1404 	char *tmpbuf;
1405 	int error = 0;
1406 
1407 	/*
1408 	 * Set credits in our softc
1409 	 */
1410 
1411 	if (sc->cred)
1412 		crfree(sc->cred);
1413 	sc->cred = crhold(cred);
1414 
1415 	/*
1416 	 * Horrible kludge to establish credentials for NFS  XXX.
1417 	 */
1418 
1419 	if (sc->type == MD_VNODE && sc->s_vnode.vnode != NULL) {
1420 		struct uio auio;
1421 		struct iovec aiov;
1422 
1423 		tmpbuf = malloc(sc->sectorsize, M_TEMP, M_WAITOK);
1424 		bzero(&auio, sizeof(auio));
1425 
1426 		aiov.iov_base = tmpbuf;
1427 		aiov.iov_len = sc->sectorsize;
1428 		auio.uio_iov = &aiov;
1429 		auio.uio_iovcnt = 1;
1430 		auio.uio_offset = 0;
1431 		auio.uio_rw = UIO_READ;
1432 		auio.uio_segflg = UIO_SYSSPACE;
1433 		auio.uio_resid = aiov.iov_len;
1434 		vn_lock(sc->s_vnode.vnode, LK_EXCLUSIVE | LK_RETRY);
1435 		error = VOP_READ(sc->s_vnode.vnode, &auio, 0, sc->cred);
1436 		VOP_UNLOCK(sc->s_vnode.vnode);
1437 		free(tmpbuf, M_TEMP);
1438 	}
1439 	return (error);
1440 }
1441 
1442 static int
mdcreate_vnode(struct md_s * sc,struct md_req * mdr,struct thread * td)1443 mdcreate_vnode(struct md_s *sc, struct md_req *mdr, struct thread *td)
1444 {
1445 	struct vattr vattr;
1446 	struct nameidata nd;
1447 	char *fname;
1448 	int error, flags;
1449 	long v;
1450 
1451 	fname = mdr->md_file;
1452 	if (mdr->md_file_seg == UIO_USERSPACE) {
1453 		error = copyinstr(fname, sc->s_vnode.file,
1454 		    sizeof(sc->s_vnode.file), NULL);
1455 		if (error != 0)
1456 			return (error);
1457 	} else if (mdr->md_file_seg == UIO_SYSSPACE)
1458 		strlcpy(sc->s_vnode.file, fname, sizeof(sc->s_vnode.file));
1459 	else
1460 		return (EDOOFUS);
1461 
1462 	/*
1463 	 * If the user specified that this is a read only device, don't
1464 	 * set the FWRITE mask before trying to open the backing store.
1465 	 */
1466 	flags = FREAD | ((mdr->md_options & MD_READONLY) ? 0 : FWRITE) \
1467 	    | ((mdr->md_options & MD_VERIFY) ? O_VERIFY : 0);
1468 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, sc->s_vnode.file);
1469 	error = vn_open(&nd, &flags, 0, NULL);
1470 	if (error != 0)
1471 		return (error);
1472 	NDFREE_PNBUF(&nd);
1473 	if (nd.ni_vp->v_type != VREG) {
1474 		error = EINVAL;
1475 		goto bad;
1476 	}
1477 	error = VOP_GETATTR(nd.ni_vp, &vattr, td->td_ucred);
1478 	if (error != 0)
1479 		goto bad;
1480 	if ((mdr->md_options & MD_MUSTDEALLOC) != 0) {
1481 		error = VOP_PATHCONF(nd.ni_vp, _PC_DEALLOC_PRESENT, &v);
1482 		if (error != 0)
1483 			goto bad;
1484 		if (v == 0)
1485 			sc->candelete = false;
1486 	}
1487 	if (VOP_ISLOCKED(nd.ni_vp) != LK_EXCLUSIVE) {
1488 		vn_lock(nd.ni_vp, LK_UPGRADE | LK_RETRY);
1489 		if (VN_IS_DOOMED(nd.ni_vp)) {
1490 			/* Forced unmount. */
1491 			error = EBADF;
1492 			goto bad;
1493 		}
1494 	}
1495 	nd.ni_vp->v_vflag |= VV_MD;
1496 	VOP_UNLOCK(nd.ni_vp);
1497 
1498 	if (mdr->md_fwsectors != 0)
1499 		sc->fwsectors = mdr->md_fwsectors;
1500 	if (mdr->md_fwheads != 0)
1501 		sc->fwheads = mdr->md_fwheads;
1502 	snprintf(sc->ident, sizeof(sc->ident), "MD-DEV%ju-INO%ju",
1503 	    (uintmax_t)vattr.va_fsid, (uintmax_t)vattr.va_fileid);
1504 	sc->flags = mdr->md_options & (MD_ASYNC | MD_CACHE | MD_FORCE |
1505 	    MD_VERIFY | MD_MUSTDEALLOC);
1506 	if (!(flags & FWRITE))
1507 		sc->flags |= MD_READONLY;
1508 	sc->s_vnode.vnode = nd.ni_vp;
1509 
1510 	error = mdsetcred(sc, td->td_ucred);
1511 	if (error != 0) {
1512 		sc->s_vnode.vnode = NULL;
1513 		vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
1514 		nd.ni_vp->v_vflag &= ~VV_MD;
1515 		goto bad;
1516 	}
1517 
1518 	sc->s_vnode.kva = kva_alloc(maxphys + PAGE_SIZE);
1519 	return (0);
1520 bad:
1521 	VOP_UNLOCK(nd.ni_vp);
1522 	(void)vn_close(nd.ni_vp, flags, td->td_ucred, td);
1523 	return (error);
1524 }
1525 
1526 static void
g_md_providergone(struct g_provider * pp)1527 g_md_providergone(struct g_provider *pp)
1528 {
1529 	struct md_s *sc = pp->geom->softc;
1530 
1531 	mtx_lock(&sc->queue_mtx);
1532 	sc->flags |= MD_PROVIDERGONE;
1533 	wakeup(&sc->flags);
1534 	mtx_unlock(&sc->queue_mtx);
1535 }
1536 
1537 static int
mddestroy(struct md_s * sc,struct thread * td)1538 mddestroy(struct md_s *sc, struct thread *td)
1539 {
1540 
1541 	if (sc->gp) {
1542 		g_topology_lock();
1543 		g_wither_geom(sc->gp, ENXIO);
1544 		g_topology_unlock();
1545 
1546 		mtx_lock(&sc->queue_mtx);
1547 		while (!(sc->flags & MD_PROVIDERGONE))
1548 			msleep(&sc->flags, &sc->queue_mtx, PRIBIO, "mddestroy", 0);
1549 		mtx_unlock(&sc->queue_mtx);
1550 	}
1551 	if (sc->devstat) {
1552 		devstat_remove_entry(sc->devstat);
1553 		sc->devstat = NULL;
1554 	}
1555 	mtx_lock(&sc->queue_mtx);
1556 	sc->flags |= MD_SHUTDOWN;
1557 	wakeup(sc);
1558 	while (!(sc->flags & MD_EXITING))
1559 		msleep(sc->procp, &sc->queue_mtx, PRIBIO, "mddestroy", hz / 10);
1560 	mtx_unlock(&sc->queue_mtx);
1561 	mtx_destroy(&sc->queue_mtx);
1562 	switch (sc->type) {
1563 	case MD_VNODE:
1564 		if (sc->s_vnode.vnode != NULL) {
1565 			vn_lock(sc->s_vnode.vnode, LK_EXCLUSIVE | LK_RETRY);
1566 			sc->s_vnode.vnode->v_vflag &= ~VV_MD;
1567 			VOP_UNLOCK(sc->s_vnode.vnode);
1568 			(void)vn_close(sc->s_vnode.vnode,
1569 			    sc->flags & MD_READONLY ?  FREAD : (FREAD|FWRITE),
1570 			    sc->cred, td);
1571 		}
1572 		if (sc->s_vnode.kva != 0)
1573 			kva_free(sc->s_vnode.kva, maxphys + PAGE_SIZE);
1574 		break;
1575 	case MD_SWAP:
1576 		if (sc->s_swap.object != NULL)
1577 			vm_object_deallocate(sc->s_swap.object);
1578 		break;
1579 	case MD_MALLOC:
1580 		if (sc->s_malloc.indir != NULL)
1581 			destroy_indir(sc, sc->s_malloc.indir);
1582 		if (sc->s_malloc.uma != NULL)
1583 			uma_zdestroy(sc->s_malloc.uma);
1584 		break;
1585 	case MD_PRELOAD:
1586 	case MD_NULL:
1587 		break;
1588 	default:
1589 		__assert_unreachable();
1590 	}
1591 	if (sc->cred != NULL)
1592 		crfree(sc->cred);
1593 
1594 	LIST_REMOVE(sc, list);
1595 	free_unr(md_uh, sc->unit);
1596 	free(sc, M_MD);
1597 	return (0);
1598 }
1599 
1600 static int
mdresize(struct md_s * sc,struct md_req * mdr)1601 mdresize(struct md_s *sc, struct md_req *mdr)
1602 {
1603 	int error, res;
1604 	vm_pindex_t oldpages, newpages;
1605 
1606 	switch (sc->type) {
1607 	case MD_VNODE:
1608 	case MD_NULL:
1609 		break;
1610 	case MD_SWAP:
1611 		if (mdr->md_mediasize <= 0 ||
1612 		    (mdr->md_mediasize % PAGE_SIZE) != 0)
1613 			return (EDOM);
1614 		oldpages = OFF_TO_IDX(sc->mediasize);
1615 		newpages = OFF_TO_IDX(mdr->md_mediasize);
1616 		if (newpages < oldpages) {
1617 			VM_OBJECT_WLOCK(sc->s_swap.object);
1618 			vm_object_page_remove(sc->s_swap.object, newpages,
1619 			    0, 0);
1620 			swap_release_by_cred(IDX_TO_OFF(oldpages -
1621 			    newpages), sc->cred);
1622 			sc->s_swap.object->charge = IDX_TO_OFF(newpages);
1623 			sc->s_swap.object->size = newpages;
1624 			VM_OBJECT_WUNLOCK(sc->s_swap.object);
1625 		} else if (newpages > oldpages) {
1626 			res = swap_reserve_by_cred(IDX_TO_OFF(newpages -
1627 			    oldpages), sc->cred);
1628 			if (!res)
1629 				return (ENOMEM);
1630 			if ((mdr->md_options & MD_RESERVE) ||
1631 			    (sc->flags & MD_RESERVE)) {
1632 				error = swap_pager_reserve(sc->s_swap.object,
1633 				    oldpages, newpages - oldpages);
1634 				if (error < 0) {
1635 					swap_release_by_cred(
1636 					    IDX_TO_OFF(newpages - oldpages),
1637 					    sc->cred);
1638 					return (EDOM);
1639 				}
1640 			}
1641 			VM_OBJECT_WLOCK(sc->s_swap.object);
1642 			sc->s_swap.object->charge = IDX_TO_OFF(newpages);
1643 			sc->s_swap.object->size = newpages;
1644 			VM_OBJECT_WUNLOCK(sc->s_swap.object);
1645 		}
1646 		break;
1647 	default:
1648 		return (EOPNOTSUPP);
1649 	}
1650 
1651 	sc->mediasize = mdr->md_mediasize;
1652 
1653 	g_topology_lock();
1654 	g_resize_provider(sc->pp, sc->mediasize);
1655 	g_topology_unlock();
1656 	return (0);
1657 }
1658 
1659 static int
mdcreate_swap(struct md_s * sc,struct md_req * mdr,struct thread * td)1660 mdcreate_swap(struct md_s *sc, struct md_req *mdr, struct thread *td)
1661 {
1662 	vm_ooffset_t npage;
1663 	int error;
1664 
1665 	/*
1666 	 * Range check.  Disallow negative sizes and sizes not being
1667 	 * multiple of page size.
1668 	 */
1669 	if (sc->mediasize <= 0 || (sc->mediasize % PAGE_SIZE) != 0)
1670 		return (EDOM);
1671 
1672 	/*
1673 	 * Allocate an OBJT_SWAP object.
1674 	 *
1675 	 * Note the truncation.
1676 	 */
1677 
1678 	if ((mdr->md_options & MD_VERIFY) != 0)
1679 		return (EINVAL);
1680 	npage = mdr->md_mediasize / PAGE_SIZE;
1681 	if (mdr->md_fwsectors != 0)
1682 		sc->fwsectors = mdr->md_fwsectors;
1683 	if (mdr->md_fwheads != 0)
1684 		sc->fwheads = mdr->md_fwheads;
1685 	sc->s_swap.object = vm_pager_allocate(OBJT_SWAP, NULL,
1686 	    PAGE_SIZE * npage, VM_PROT_DEFAULT, 0, td->td_ucred);
1687 	if (sc->s_swap.object == NULL)
1688 		return (ENOMEM);
1689 	sc->flags = mdr->md_options & (MD_FORCE | MD_RESERVE);
1690 	if (mdr->md_options & MD_RESERVE) {
1691 		if (swap_pager_reserve(sc->s_swap.object, 0, npage) < 0) {
1692 			error = EDOM;
1693 			goto finish;
1694 		}
1695 	}
1696 	error = mdsetcred(sc, td->td_ucred);
1697  finish:
1698 	if (error != 0) {
1699 		vm_object_deallocate(sc->s_swap.object);
1700 		sc->s_swap.object = NULL;
1701 	}
1702 	return (error);
1703 }
1704 
1705 static int
mdcreate_null(struct md_s * sc,struct md_req * mdr,struct thread * td)1706 mdcreate_null(struct md_s *sc, struct md_req *mdr, struct thread *td)
1707 {
1708 
1709 	/*
1710 	 * Range check.  Disallow negative sizes and sizes not being
1711 	 * multiple of page size.
1712 	 */
1713 	if (sc->mediasize <= 0 || (sc->mediasize % PAGE_SIZE) != 0)
1714 		return (EDOM);
1715 
1716 	return (0);
1717 }
1718 
1719 static int
kern_mdattach_locked(struct thread * td,struct md_req * mdr)1720 kern_mdattach_locked(struct thread *td, struct md_req *mdr)
1721 {
1722 	struct md_s *sc;
1723 	unsigned sectsize;
1724 	int error;
1725 
1726 	sx_assert(&md_sx, SA_XLOCKED);
1727 
1728 	switch (mdr->md_type) {
1729 	case MD_MALLOC:
1730 	case MD_PRELOAD:
1731 	case MD_VNODE:
1732 	case MD_SWAP:
1733 	case MD_NULL:
1734 		break;
1735 	default:
1736 		return (EINVAL);
1737 	}
1738 	if (mdr->md_sectorsize == 0)
1739 		sectsize = DEV_BSIZE;
1740 	else
1741 		sectsize = mdr->md_sectorsize;
1742 	if (sectsize > maxphys || mdr->md_mediasize < sectsize)
1743 		return (EINVAL);
1744 	if (mdr->md_options & MD_AUTOUNIT)
1745 		sc = mdnew(-1, &error, mdr->md_type);
1746 	else {
1747 		if (mdr->md_unit > INT_MAX)
1748 			return (EINVAL);
1749 		sc = mdnew(mdr->md_unit, &error, mdr->md_type);
1750 	}
1751 	if (sc == NULL)
1752 		return (error);
1753 	if (mdr->md_label != NULL)
1754 		error = copyinstr(mdr->md_label, sc->label,
1755 		    sizeof(sc->label), NULL);
1756 	if (error != 0)
1757 		goto err_after_new;
1758 	if (mdr->md_options & MD_AUTOUNIT)
1759 		mdr->md_unit = sc->unit;
1760 	sc->mediasize = mdr->md_mediasize;
1761 	sc->sectorsize = sectsize;
1762 	sc->candelete = true;
1763 	error = EDOOFUS;
1764 	switch (sc->type) {
1765 	case MD_MALLOC:
1766 		sc->start = mdstart_malloc;
1767 		error = mdcreate_malloc(sc, mdr);
1768 		break;
1769 	case MD_PRELOAD:
1770 		/*
1771 		 * We disallow attaching preloaded memory disks via
1772 		 * ioctl. Preloaded memory disks are automatically
1773 		 * attached in g_md_init().
1774 		 */
1775 		error = EOPNOTSUPP;
1776 		break;
1777 	case MD_VNODE:
1778 		sc->start = mdstart_vnode;
1779 		error = mdcreate_vnode(sc, mdr, td);
1780 		break;
1781 	case MD_SWAP:
1782 		sc->start = mdstart_swap;
1783 		error = mdcreate_swap(sc, mdr, td);
1784 		break;
1785 	case MD_NULL:
1786 		sc->start = mdstart_null;
1787 		error = mdcreate_null(sc, mdr, td);
1788 		break;
1789 	}
1790 err_after_new:
1791 	if (error != 0) {
1792 		mddestroy(sc, td);
1793 		return (error);
1794 	}
1795 
1796 	mdinit(sc);
1797 	return (0);
1798 }
1799 
1800 static int
kern_mdattach(struct thread * td,struct md_req * mdr)1801 kern_mdattach(struct thread *td, struct md_req *mdr)
1802 {
1803 	int error;
1804 
1805 	sx_xlock(&md_sx);
1806 	error = kern_mdattach_locked(td, mdr);
1807 	sx_xunlock(&md_sx);
1808 	return (error);
1809 }
1810 
1811 static int
kern_mddetach_locked(struct thread * td,struct md_req * mdr)1812 kern_mddetach_locked(struct thread *td, struct md_req *mdr)
1813 {
1814 	struct md_s *sc;
1815 
1816 	sx_assert(&md_sx, SA_XLOCKED);
1817 
1818 	if (mdr->md_mediasize != 0 ||
1819 	    (mdr->md_options & ~MD_FORCE) != 0)
1820 		return (EINVAL);
1821 
1822 	sc = mdfind(mdr->md_unit);
1823 	if (sc == NULL)
1824 		return (ENOENT);
1825 	if (sc->opencount != 0 && !(sc->flags & MD_FORCE) &&
1826 	    !(mdr->md_options & MD_FORCE))
1827 		return (EBUSY);
1828 	return (mddestroy(sc, td));
1829 }
1830 
1831 static int
kern_mddetach(struct thread * td,struct md_req * mdr)1832 kern_mddetach(struct thread *td, struct md_req *mdr)
1833 {
1834 	int error;
1835 
1836 	sx_xlock(&md_sx);
1837 	error = kern_mddetach_locked(td, mdr);
1838 	sx_xunlock(&md_sx);
1839 	return (error);
1840 }
1841 
1842 static int
kern_mdresize_locked(struct md_req * mdr)1843 kern_mdresize_locked(struct md_req *mdr)
1844 {
1845 	struct md_s *sc;
1846 
1847 	sx_assert(&md_sx, SA_XLOCKED);
1848 
1849 	if ((mdr->md_options & ~(MD_FORCE | MD_RESERVE)) != 0)
1850 		return (EINVAL);
1851 
1852 	sc = mdfind(mdr->md_unit);
1853 	if (sc == NULL)
1854 		return (ENOENT);
1855 	if (mdr->md_mediasize < sc->sectorsize)
1856 		return (EINVAL);
1857 	mdr->md_mediasize -= mdr->md_mediasize % sc->sectorsize;
1858 	if (mdr->md_mediasize < sc->mediasize &&
1859 	    !(sc->flags & MD_FORCE) &&
1860 	    !(mdr->md_options & MD_FORCE))
1861 		return (EBUSY);
1862 	return (mdresize(sc, mdr));
1863 }
1864 
1865 static int
kern_mdresize(struct md_req * mdr)1866 kern_mdresize(struct md_req *mdr)
1867 {
1868 	int error;
1869 
1870 	sx_xlock(&md_sx);
1871 	error = kern_mdresize_locked(mdr);
1872 	sx_xunlock(&md_sx);
1873 	return (error);
1874 }
1875 
1876 static int
kern_mdquery_locked(struct md_req * mdr)1877 kern_mdquery_locked(struct md_req *mdr)
1878 {
1879 	struct md_s *sc;
1880 	int error;
1881 
1882 	sx_assert(&md_sx, SA_XLOCKED);
1883 
1884 	sc = mdfind(mdr->md_unit);
1885 	if (sc == NULL)
1886 		return (ENOENT);
1887 	mdr->md_type = sc->type;
1888 	mdr->md_options = sc->flags;
1889 	mdr->md_mediasize = sc->mediasize;
1890 	mdr->md_sectorsize = sc->sectorsize;
1891 	error = 0;
1892 	if (mdr->md_label != NULL) {
1893 		error = copyout(sc->label, mdr->md_label,
1894 		    strlen(sc->label) + 1);
1895 		if (error != 0)
1896 			return (error);
1897 	}
1898 	if (sc->type == MD_VNODE) {
1899 		error = copyout(sc->s_vnode.file, mdr->md_file,
1900 		    strlen(sc->s_vnode.file) + 1);
1901 	} else if (sc->type == MD_PRELOAD && mdr->md_file != NULL) {
1902 		error = copyout(sc->s_preload.name, mdr->md_file,
1903 		    strlen(sc->s_preload.name) + 1);
1904 	}
1905 	return (error);
1906 }
1907 
1908 static int
kern_mdquery(struct md_req * mdr)1909 kern_mdquery(struct md_req *mdr)
1910 {
1911 	int error;
1912 
1913 	sx_xlock(&md_sx);
1914 	error = kern_mdquery_locked(mdr);
1915 	sx_xunlock(&md_sx);
1916 	return (error);
1917 }
1918 
1919 /* Copy members that are not userspace pointers. */
1920 #define	MD_IOCTL2REQ(mdio, mdr) do {					\
1921 	(mdr)->md_unit = (mdio)->md_unit;				\
1922 	(mdr)->md_type = (mdio)->md_type;				\
1923 	(mdr)->md_mediasize = (mdio)->md_mediasize;			\
1924 	(mdr)->md_sectorsize = (mdio)->md_sectorsize;			\
1925 	(mdr)->md_options = (mdio)->md_options;				\
1926 	(mdr)->md_fwheads = (mdio)->md_fwheads;				\
1927 	(mdr)->md_fwsectors = (mdio)->md_fwsectors;			\
1928 	(mdr)->md_units = &(mdio)->md_pad[0];				\
1929 	(mdr)->md_units_nitems = nitems((mdio)->md_pad);		\
1930 } while(0)
1931 
1932 /* Copy members that might have been updated */
1933 #define MD_REQ2IOCTL(mdr, mdio) do {					\
1934 	(mdio)->md_unit = (mdr)->md_unit;				\
1935 	(mdio)->md_type = (mdr)->md_type;				\
1936 	(mdio)->md_mediasize = (mdr)->md_mediasize;			\
1937 	(mdio)->md_sectorsize = (mdr)->md_sectorsize;			\
1938 	(mdio)->md_options = (mdr)->md_options;				\
1939 	(mdio)->md_fwheads = (mdr)->md_fwheads;				\
1940 	(mdio)->md_fwsectors = (mdr)->md_fwsectors;			\
1941 } while(0)
1942 
1943 static int
mdctlioctl(struct cdev * dev,u_long cmd,caddr_t addr,int flags,struct thread * td)1944 mdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
1945     struct thread *td)
1946 {
1947 	struct md_req mdr;
1948 	int error;
1949 
1950 	if (md_debug)
1951 		printf("mdctlioctl(%s %lx %p %x %p)\n",
1952 			devtoname(dev), cmd, addr, flags, td);
1953 
1954 	bzero(&mdr, sizeof(mdr));
1955 	switch (cmd) {
1956 	case MDIOCATTACH:
1957 	case MDIOCDETACH:
1958 	case MDIOCRESIZE:
1959 	case MDIOCQUERY: {
1960 		struct md_ioctl *mdio = (struct md_ioctl *)addr;
1961 		if (mdio->md_version != MDIOVERSION)
1962 			return (EINVAL);
1963 		MD_IOCTL2REQ(mdio, &mdr);
1964 		mdr.md_file = mdio->md_file;
1965 		mdr.md_file_seg = UIO_USERSPACE;
1966 		/* If the file is adjacent to the md_ioctl it's in kernel. */
1967 		if ((void *)mdio->md_file == (void *)(mdio + 1))
1968 			mdr.md_file_seg = UIO_SYSSPACE;
1969 		mdr.md_label = mdio->md_label;
1970 		break;
1971 	}
1972 #ifdef COMPAT_FREEBSD32
1973 	case MDIOCATTACH_32:
1974 	case MDIOCDETACH_32:
1975 	case MDIOCRESIZE_32:
1976 	case MDIOCQUERY_32: {
1977 		struct md_ioctl32 *mdio = (struct md_ioctl32 *)addr;
1978 		if (mdio->md_version != MDIOVERSION)
1979 			return (EINVAL);
1980 		MD_IOCTL2REQ(mdio, &mdr);
1981 		mdr.md_file = (void *)(uintptr_t)mdio->md_file;
1982 		mdr.md_file_seg = UIO_USERSPACE;
1983 		mdr.md_label = (void *)(uintptr_t)mdio->md_label;
1984 		break;
1985 	}
1986 #endif
1987 	default:
1988 		/* Fall through to handler switch. */
1989 		break;
1990 	}
1991 
1992 	error = 0;
1993 	switch (cmd) {
1994 	case MDIOCATTACH:
1995 #ifdef COMPAT_FREEBSD32
1996 	case MDIOCATTACH_32:
1997 #endif
1998 		error = kern_mdattach(td, &mdr);
1999 		break;
2000 	case MDIOCDETACH:
2001 #ifdef COMPAT_FREEBSD32
2002 	case MDIOCDETACH_32:
2003 #endif
2004 		error = kern_mddetach(td, &mdr);
2005 		break;
2006 	case MDIOCRESIZE:
2007 #ifdef COMPAT_FREEBSD32
2008 	case MDIOCRESIZE_32:
2009 #endif
2010 		error = kern_mdresize(&mdr);
2011 		break;
2012 	case MDIOCQUERY:
2013 #ifdef COMPAT_FREEBSD32
2014 	case MDIOCQUERY_32:
2015 #endif
2016 		error = kern_mdquery(&mdr);
2017 		break;
2018 	default:
2019 		error = ENOIOCTL;
2020 	}
2021 
2022 	switch (cmd) {
2023 	case MDIOCATTACH:
2024 	case MDIOCQUERY: {
2025 		struct md_ioctl *mdio = (struct md_ioctl *)addr;
2026 		MD_REQ2IOCTL(&mdr, mdio);
2027 		break;
2028 	}
2029 #ifdef COMPAT_FREEBSD32
2030 	case MDIOCATTACH_32:
2031 	case MDIOCQUERY_32: {
2032 		struct md_ioctl32 *mdio = (struct md_ioctl32 *)addr;
2033 		MD_REQ2IOCTL(&mdr, mdio);
2034 		break;
2035 	}
2036 #endif
2037 	default:
2038 		/* Other commands to not alter mdr. */
2039 		break;
2040 	}
2041 
2042 	return (error);
2043 }
2044 
2045 static void
md_preloaded(u_char * image,size_t length,const char * name)2046 md_preloaded(u_char *image, size_t length, const char *name)
2047 {
2048 	struct md_s *sc;
2049 	int error;
2050 
2051 	sc = mdnew(-1, &error, MD_PRELOAD);
2052 	if (sc == NULL)
2053 		return;
2054 	sc->mediasize = length;
2055 	sc->sectorsize = DEV_BSIZE;
2056 	sc->s_preload.pl_ptr = image;
2057 	sc->s_preload.pl_len = length;
2058 	sc->start = mdstart_preload;
2059 	if (name != NULL)
2060 		strlcpy(sc->s_preload.name, name,
2061 		    sizeof(sc->s_preload.name));
2062 #ifdef MD_ROOT
2063 	if (sc->unit == 0) {
2064 #ifndef ROOTDEVNAME
2065 		rootdevnames[0] = MD_ROOT_FSTYPE ":/dev/md0";
2066 #endif
2067 #ifdef MD_ROOT_READONLY
2068 		sc->flags |= MD_READONLY;
2069 #endif
2070 	}
2071 #endif
2072 	mdinit(sc);
2073 	if (name != NULL) {
2074 		printf("%s%d: Preloaded image <%s> %zd bytes at %p\n",
2075 		    MD_NAME, sc->unit, name, length, image);
2076 	} else {
2077 		printf("%s%d: Embedded image %zd bytes at %p\n",
2078 		    MD_NAME, sc->unit, length, image);
2079 	}
2080 }
2081 
2082 static void
g_md_init(struct g_class * mp __unused)2083 g_md_init(struct g_class *mp __unused)
2084 {
2085 	caddr_t mod;
2086 	u_char *ptr, *name, *type;
2087 	u_char scratch[40];
2088 	unsigned len;
2089 	int i;
2090 	vm_offset_t paddr;
2091 
2092 	/* figure out log2(NINDIR) */
2093 	for (i = NINDIR, nshift = -1; i; nshift++)
2094 		i >>= 1;
2095 
2096 	mod = NULL;
2097 	sx_init(&md_sx, "MD config lock");
2098 	g_topology_unlock();
2099 	md_uh = new_unrhdr(0, INT_MAX, NULL);
2100 #ifdef MD_ROOT
2101 	if (mfs_root_size != 0) {
2102 		sx_xlock(&md_sx);
2103 #ifdef MD_ROOT_MEM
2104 		md_preloaded(mfs_root, mfs_root_size, NULL);
2105 #else
2106 		md_preloaded(__DEVOLATILE(u_char *, &mfs_root), mfs_root_size,
2107 		    NULL);
2108 #endif
2109 		sx_xunlock(&md_sx);
2110 	}
2111 #endif
2112 	/* XXX: are preload_* static or do they need Giant ? */
2113 	while ((mod = preload_search_next_name(mod)) != NULL) {
2114 		name = (char *)preload_search_info(mod, MODINFO_NAME);
2115 		if (name == NULL)
2116 			continue;
2117 		type = (char *)preload_search_info(mod, MODINFO_TYPE);
2118 		if (type == NULL)
2119 			continue;
2120 		if (strcmp(type, "md_image") && strcmp(type, "mfs_root"))
2121 			continue;
2122 		ptr = preload_fetch_addr(mod);
2123 		len = preload_fetch_size(mod);
2124 		if (ptr != NULL && len != 0) {
2125 			sx_xlock(&md_sx);
2126 			md_preloaded(ptr, len, name);
2127 			sx_xunlock(&md_sx);
2128 		}
2129 	}
2130 
2131 	/*
2132 	 * Load up to 32 pre-loaded disks
2133 	 */
2134 	for (int i = 0; i < 32; i++) {
2135 		if (resource_long_value("md", i, "physaddr",
2136 			(long *) &paddr) != 0 ||
2137 		    resource_int_value("md", i, "len", &len) != 0)
2138 		        break;
2139 		ptr = (char *)pmap_map(NULL, paddr, paddr + len, VM_PROT_READ);
2140 		if (ptr != NULL && len != 0) {
2141 			sprintf(scratch, "preload%d 0x%016jx", i,
2142 			    (uintmax_t)paddr);
2143 			sx_xlock(&md_sx);
2144 			md_preloaded(ptr, len, scratch);
2145 			sx_xunlock(&md_sx);
2146 		}
2147 	}
2148 
2149 	status_dev = make_dev(&mdctl_cdevsw, INT_MAX, UID_ROOT, GID_WHEEL,
2150 	    0600, MDCTL_NAME);
2151 	g_topology_lock();
2152 }
2153 
2154 static void
g_md_dumpconf(struct sbuf * sb,const char * indent,struct g_geom * gp,struct g_consumer * cp __unused,struct g_provider * pp)2155 g_md_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
2156     struct g_consumer *cp __unused, struct g_provider *pp)
2157 {
2158 	struct md_s *mp;
2159 	char *type;
2160 
2161 	mp = gp->softc;
2162 	if (mp == NULL)
2163 		return;
2164 
2165 	switch (mp->type) {
2166 	case MD_MALLOC:
2167 		type = "malloc";
2168 		break;
2169 	case MD_PRELOAD:
2170 		type = "preload";
2171 		break;
2172 	case MD_VNODE:
2173 		type = "vnode";
2174 		break;
2175 	case MD_SWAP:
2176 		type = "swap";
2177 		break;
2178 	case MD_NULL:
2179 		type = "null";
2180 		break;
2181 	default:
2182 		type = "unknown";
2183 		break;
2184 	}
2185 
2186 	if (pp != NULL) {
2187 		if (indent == NULL) {
2188 			sbuf_printf(sb, " u %d", mp->unit);
2189 			sbuf_printf(sb, " s %ju", (uintmax_t) mp->sectorsize);
2190 			sbuf_printf(sb, " f %ju", (uintmax_t) mp->fwheads);
2191 			sbuf_printf(sb, " fs %ju", (uintmax_t) mp->fwsectors);
2192 			sbuf_printf(sb, " l %ju", (uintmax_t) mp->mediasize);
2193 			sbuf_printf(sb, " t %s", type);
2194 			if (mp->type == MD_VNODE &&
2195 			    mp->s_vnode.vnode != NULL)
2196 				sbuf_printf(sb, " file %s", mp->s_vnode.file);
2197 			if (mp->type == MD_PRELOAD &&
2198 			    mp->s_preload.name[0] != '\0') {
2199 				sbuf_printf(sb, " file %s",
2200 				    mp->s_preload.name);
2201 			}
2202 			sbuf_printf(sb, " label %s", mp->label);
2203 		} else {
2204 			sbuf_printf(sb, "%s<unit>%d</unit>\n", indent,
2205 			    mp->unit);
2206 			sbuf_printf(sb, "%s<sectorsize>%ju</sectorsize>\n",
2207 			    indent, (uintmax_t) mp->sectorsize);
2208 			sbuf_printf(sb, "%s<fwheads>%ju</fwheads>\n",
2209 			    indent, (uintmax_t) mp->fwheads);
2210 			sbuf_printf(sb, "%s<fwsectors>%ju</fwsectors>\n",
2211 			    indent, (uintmax_t) mp->fwsectors);
2212 			if (mp->ident[0] != '\0') {
2213 				sbuf_printf(sb, "%s<ident>", indent);
2214 				g_conf_printf_escaped(sb, "%s", mp->ident);
2215 				sbuf_printf(sb, "</ident>\n");
2216 			}
2217 			sbuf_printf(sb, "%s<length>%ju</length>\n",
2218 			    indent, (uintmax_t) mp->mediasize);
2219 			sbuf_printf(sb, "%s<compression>%s</compression>\n", indent,
2220 			    (mp->flags & MD_COMPRESS) == 0 ? "off": "on");
2221 			sbuf_printf(sb, "%s<access>%s</access>\n", indent,
2222 			    (mp->flags & MD_READONLY) == 0 ? "read-write":
2223 			    "read-only");
2224 			sbuf_printf(sb, "%s<type>%s</type>\n", indent,
2225 			    type);
2226 			if (mp->type == MD_VNODE) {
2227 				if (mp->s_vnode.vnode != NULL) {
2228 					sbuf_printf(sb, "%s<file>", indent);
2229 					g_conf_printf_escaped(sb, "%s",
2230 					    mp->s_vnode.file);
2231 					sbuf_printf(sb, "</file>\n");
2232 				}
2233 				sbuf_printf(sb, "%s<cache>%s</cache>\n", indent,
2234 				    (mp->flags & MD_CACHE) == 0 ? "off": "on");
2235 			}
2236 			if (mp->type == MD_PRELOAD &&
2237 			    mp->s_preload.name[0] != '\0') {
2238 				sbuf_printf(sb, "%s<file>", indent);
2239 				g_conf_printf_escaped(sb, "%s",
2240 				    mp->s_preload.name);
2241 				sbuf_printf(sb, "</file>\n");
2242 			}
2243 			sbuf_printf(sb, "%s<label>", indent);
2244 			g_conf_printf_escaped(sb, "%s", mp->label);
2245 			sbuf_printf(sb, "</label>\n");
2246 		}
2247 	}
2248 }
2249 
2250 static void
g_md_fini(struct g_class * mp __unused)2251 g_md_fini(struct g_class *mp __unused)
2252 {
2253 
2254 	sx_destroy(&md_sx);
2255 	if (status_dev != NULL)
2256 		destroy_dev(status_dev);
2257 	delete_unrhdr(md_uh);
2258 }
2259