xref: /freebsd/sys/dev/md/md.c (revision aa0a1e58)
1 /*-
2  * ----------------------------------------------------------------------------
3  * "THE BEER-WARE LICENSE" (Revision 42):
4  * <phk@FreeBSD.ORG> wrote this file.  As long as you retain this notice you
5  * can do whatever you want with this stuff. If we meet some day, and you think
6  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
7  * ----------------------------------------------------------------------------
8  *
9  * $FreeBSD$
10  *
11  */
12 
13 /*-
14  * The following functions are based in the vn(4) driver: mdstart_swap(),
15  * mdstart_vnode(), mdcreate_swap(), mdcreate_vnode() and mddestroy(),
16  * 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  *
22  * This code is derived from software contributed to Berkeley by
23  * the Systems Programming Group of the University of Utah Computer
24  * Science Department.
25  *
26  * Redistribution and use in source and binary forms, with or without
27  * modification, are permitted provided that the following conditions
28  * are met:
29  * 1. Redistributions of source code must retain the above copyright
30  *    notice, this list of conditions and the following disclaimer.
31  * 2. Redistributions in binary form must reproduce the above copyright
32  *    notice, this list of conditions and the following disclaimer in the
33  *    documentation and/or other materials provided with the distribution.
34  * 4. Neither the name of the University nor the names of its contributors
35  *    may be used to endorse or promote products derived from this software
36  *    without specific prior written permission.
37  *
38  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
39  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
41  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
42  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
43  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
44  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
45  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
46  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
47  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48  * SUCH DAMAGE.
49  *
50  * from: Utah Hdr: vn.c 1.13 94/04/02
51  *
52  *	from: @(#)vn.c	8.6 (Berkeley) 4/1/94
53  * From: src/sys/dev/vn/vn.c,v 1.122 2000/12/16 16:06:03
54  */
55 
56 #include "opt_geom.h"
57 #include "opt_md.h"
58 
59 #include <sys/param.h>
60 #include <sys/systm.h>
61 #include <sys/bio.h>
62 #include <sys/conf.h>
63 #include <sys/devicestat.h>
64 #include <sys/fcntl.h>
65 #include <sys/kernel.h>
66 #include <sys/kthread.h>
67 #include <sys/limits.h>
68 #include <sys/linker.h>
69 #include <sys/lock.h>
70 #include <sys/malloc.h>
71 #include <sys/mdioctl.h>
72 #include <sys/mount.h>
73 #include <sys/mutex.h>
74 #include <sys/sx.h>
75 #include <sys/namei.h>
76 #include <sys/proc.h>
77 #include <sys/queue.h>
78 #include <sys/sched.h>
79 #include <sys/sf_buf.h>
80 #include <sys/sysctl.h>
81 #include <sys/vnode.h>
82 
83 #include <geom/geom.h>
84 
85 #include <vm/vm.h>
86 #include <vm/vm_object.h>
87 #include <vm/vm_page.h>
88 #include <vm/vm_pager.h>
89 #include <vm/swap_pager.h>
90 #include <vm/uma.h>
91 
92 #define MD_MODVER 1
93 
94 #define MD_SHUTDOWN	0x10000		/* Tell worker thread to terminate. */
95 #define	MD_EXITING	0x20000		/* Worker thread is exiting. */
96 
97 #ifndef MD_NSECT
98 #define MD_NSECT (10000 * 2)
99 #endif
100 
101 static MALLOC_DEFINE(M_MD, "md_disk", "Memory Disk");
102 static MALLOC_DEFINE(M_MDSECT, "md_sectors", "Memory Disk Sectors");
103 
104 static int md_debug;
105 SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0, "");
106 static int md_malloc_wait;
107 SYSCTL_INT(_vm, OID_AUTO, md_malloc_wait, CTLFLAG_RW, &md_malloc_wait, 0, "");
108 
109 #if defined(MD_ROOT) && defined(MD_ROOT_SIZE)
110 /*
111  * Preloaded image gets put here.
112  * Applications that patch the object with the image can determine
113  * the size looking at the start and end markers (strings),
114  * so we want them contiguous.
115  */
116 static struct {
117 	u_char start[MD_ROOT_SIZE*1024];
118 	u_char end[128];
119 } mfs_root = {
120 	.start = "MFS Filesystem goes here",
121 	.end = "MFS Filesystem had better STOP here",
122 };
123 #endif
124 
125 static g_init_t g_md_init;
126 static g_fini_t g_md_fini;
127 static g_start_t g_md_start;
128 static g_access_t g_md_access;
129 static void g_md_dumpconf(struct sbuf *sb, const char *indent,
130     struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp);
131 
132 static int mdunits;
133 static struct cdev *status_dev = 0;
134 static struct sx md_sx;
135 static struct unrhdr *md_uh;
136 
137 static d_ioctl_t mdctlioctl;
138 
139 static struct cdevsw mdctl_cdevsw = {
140 	.d_version =	D_VERSION,
141 	.d_ioctl =	mdctlioctl,
142 	.d_name =	MD_NAME,
143 };
144 
145 struct g_class g_md_class = {
146 	.name = "MD",
147 	.version = G_VERSION,
148 	.init = g_md_init,
149 	.fini = g_md_fini,
150 	.start = g_md_start,
151 	.access = g_md_access,
152 	.dumpconf = g_md_dumpconf,
153 };
154 
155 DECLARE_GEOM_CLASS(g_md_class, g_md);
156 
157 
158 static LIST_HEAD(, md_s) md_softc_list = LIST_HEAD_INITIALIZER(md_softc_list);
159 
160 #define NINDIR	(PAGE_SIZE / sizeof(uintptr_t))
161 #define NMASK	(NINDIR-1)
162 static int nshift;
163 
164 struct indir {
165 	uintptr_t	*array;
166 	u_int		total;
167 	u_int		used;
168 	u_int		shift;
169 };
170 
171 struct md_s {
172 	int unit;
173 	LIST_ENTRY(md_s) list;
174 	struct bio_queue_head bio_queue;
175 	struct mtx queue_mtx;
176 	struct cdev *dev;
177 	enum md_types type;
178 	off_t mediasize;
179 	unsigned sectorsize;
180 	unsigned opencount;
181 	unsigned fwheads;
182 	unsigned fwsectors;
183 	unsigned flags;
184 	char name[20];
185 	struct proc *procp;
186 	struct g_geom *gp;
187 	struct g_provider *pp;
188 	int (*start)(struct md_s *sc, struct bio *bp);
189 	struct devstat *devstat;
190 
191 	/* MD_MALLOC related fields */
192 	struct indir *indir;
193 	uma_zone_t uma;
194 
195 	/* MD_PRELOAD related fields */
196 	u_char *pl_ptr;
197 	size_t pl_len;
198 
199 	/* MD_VNODE related fields */
200 	struct vnode *vnode;
201 	char file[PATH_MAX];
202 	struct ucred *cred;
203 
204 	/* MD_SWAP related fields */
205 	vm_object_t object;
206 };
207 
208 static struct indir *
209 new_indir(u_int shift)
210 {
211 	struct indir *ip;
212 
213 	ip = malloc(sizeof *ip, M_MD, (md_malloc_wait ? M_WAITOK : M_NOWAIT)
214 	    | M_ZERO);
215 	if (ip == NULL)
216 		return (NULL);
217 	ip->array = malloc(sizeof(uintptr_t) * NINDIR,
218 	    M_MDSECT, (md_malloc_wait ? M_WAITOK : M_NOWAIT) | M_ZERO);
219 	if (ip->array == NULL) {
220 		free(ip, M_MD);
221 		return (NULL);
222 	}
223 	ip->total = NINDIR;
224 	ip->shift = shift;
225 	return (ip);
226 }
227 
228 static void
229 del_indir(struct indir *ip)
230 {
231 
232 	free(ip->array, M_MDSECT);
233 	free(ip, M_MD);
234 }
235 
236 static void
237 destroy_indir(struct md_s *sc, struct indir *ip)
238 {
239 	int i;
240 
241 	for (i = 0; i < NINDIR; i++) {
242 		if (!ip->array[i])
243 			continue;
244 		if (ip->shift)
245 			destroy_indir(sc, (struct indir*)(ip->array[i]));
246 		else if (ip->array[i] > 255)
247 			uma_zfree(sc->uma, (void *)(ip->array[i]));
248 	}
249 	del_indir(ip);
250 }
251 
252 /*
253  * This function does the math and allocates the top level "indir" structure
254  * for a device of "size" sectors.
255  */
256 
257 static struct indir *
258 dimension(off_t size)
259 {
260 	off_t rcnt;
261 	struct indir *ip;
262 	int layer;
263 
264 	rcnt = size;
265 	layer = 0;
266 	while (rcnt > NINDIR) {
267 		rcnt /= NINDIR;
268 		layer++;
269 	}
270 
271 	/*
272 	 * XXX: the top layer is probably not fully populated, so we allocate
273 	 * too much space for ip->array in here.
274 	 */
275 	ip = malloc(sizeof *ip, M_MD, M_WAITOK | M_ZERO);
276 	ip->array = malloc(sizeof(uintptr_t) * NINDIR,
277 	    M_MDSECT, M_WAITOK | M_ZERO);
278 	ip->total = NINDIR;
279 	ip->shift = layer * nshift;
280 	return (ip);
281 }
282 
283 /*
284  * Read a given sector
285  */
286 
287 static uintptr_t
288 s_read(struct indir *ip, off_t offset)
289 {
290 	struct indir *cip;
291 	int idx;
292 	uintptr_t up;
293 
294 	if (md_debug > 1)
295 		printf("s_read(%jd)\n", (intmax_t)offset);
296 	up = 0;
297 	for (cip = ip; cip != NULL;) {
298 		if (cip->shift) {
299 			idx = (offset >> cip->shift) & NMASK;
300 			up = cip->array[idx];
301 			cip = (struct indir *)up;
302 			continue;
303 		}
304 		idx = offset & NMASK;
305 		return (cip->array[idx]);
306 	}
307 	return (0);
308 }
309 
310 /*
311  * Write a given sector, prune the tree if the value is 0
312  */
313 
314 static int
315 s_write(struct indir *ip, off_t offset, uintptr_t ptr)
316 {
317 	struct indir *cip, *lip[10];
318 	int idx, li;
319 	uintptr_t up;
320 
321 	if (md_debug > 1)
322 		printf("s_write(%jd, %p)\n", (intmax_t)offset, (void *)ptr);
323 	up = 0;
324 	li = 0;
325 	cip = ip;
326 	for (;;) {
327 		lip[li++] = cip;
328 		if (cip->shift) {
329 			idx = (offset >> cip->shift) & NMASK;
330 			up = cip->array[idx];
331 			if (up != 0) {
332 				cip = (struct indir *)up;
333 				continue;
334 			}
335 			/* Allocate branch */
336 			cip->array[idx] =
337 			    (uintptr_t)new_indir(cip->shift - nshift);
338 			if (cip->array[idx] == 0)
339 				return (ENOSPC);
340 			cip->used++;
341 			up = cip->array[idx];
342 			cip = (struct indir *)up;
343 			continue;
344 		}
345 		/* leafnode */
346 		idx = offset & NMASK;
347 		up = cip->array[idx];
348 		if (up != 0)
349 			cip->used--;
350 		cip->array[idx] = ptr;
351 		if (ptr != 0)
352 			cip->used++;
353 		break;
354 	}
355 	if (cip->used != 0 || li == 1)
356 		return (0);
357 	li--;
358 	while (cip->used == 0 && cip != ip) {
359 		li--;
360 		idx = (offset >> lip[li]->shift) & NMASK;
361 		up = lip[li]->array[idx];
362 		KASSERT(up == (uintptr_t)cip, ("md screwed up"));
363 		del_indir(cip);
364 		lip[li]->array[idx] = 0;
365 		lip[li]->used--;
366 		cip = lip[li];
367 	}
368 	return (0);
369 }
370 
371 
372 static int
373 g_md_access(struct g_provider *pp, int r, int w, int e)
374 {
375 	struct md_s *sc;
376 
377 	sc = pp->geom->softc;
378 	if (sc == NULL) {
379 		if (r <= 0 && w <= 0 && e <= 0)
380 			return (0);
381 		return (ENXIO);
382 	}
383 	r += pp->acr;
384 	w += pp->acw;
385 	e += pp->ace;
386 	if ((sc->flags & MD_READONLY) != 0 && w > 0)
387 		return (EROFS);
388 	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
389 		sc->opencount = 1;
390 	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
391 		sc->opencount = 0;
392 	}
393 	return (0);
394 }
395 
396 static void
397 g_md_start(struct bio *bp)
398 {
399 	struct md_s *sc;
400 
401 	sc = bp->bio_to->geom->softc;
402 	if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
403 		devstat_start_transaction_bio(sc->devstat, bp);
404 	mtx_lock(&sc->queue_mtx);
405 	bioq_disksort(&sc->bio_queue, bp);
406 	mtx_unlock(&sc->queue_mtx);
407 	wakeup(sc);
408 }
409 
410 static int
411 mdstart_malloc(struct md_s *sc, struct bio *bp)
412 {
413 	int i, error;
414 	u_char *dst;
415 	off_t secno, nsec, uc;
416 	uintptr_t sp, osp;
417 
418 	switch (bp->bio_cmd) {
419 	case BIO_READ:
420 	case BIO_WRITE:
421 	case BIO_DELETE:
422 		break;
423 	default:
424 		return (EOPNOTSUPP);
425 	}
426 
427 	nsec = bp->bio_length / sc->sectorsize;
428 	secno = bp->bio_offset / sc->sectorsize;
429 	dst = bp->bio_data;
430 	error = 0;
431 	while (nsec--) {
432 		osp = s_read(sc->indir, secno);
433 		if (bp->bio_cmd == BIO_DELETE) {
434 			if (osp != 0)
435 				error = s_write(sc->indir, secno, 0);
436 		} else if (bp->bio_cmd == BIO_READ) {
437 			if (osp == 0)
438 				bzero(dst, sc->sectorsize);
439 			else if (osp <= 255)
440 				memset(dst, osp, sc->sectorsize);
441 			else {
442 				bcopy((void *)osp, dst, sc->sectorsize);
443 				cpu_flush_dcache(dst, sc->sectorsize);
444 			}
445 			osp = 0;
446 		} else if (bp->bio_cmd == BIO_WRITE) {
447 			if (sc->flags & MD_COMPRESS) {
448 				uc = dst[0];
449 				for (i = 1; i < sc->sectorsize; i++)
450 					if (dst[i] != uc)
451 						break;
452 			} else {
453 				i = 0;
454 				uc = 0;
455 			}
456 			if (i == sc->sectorsize) {
457 				if (osp != uc)
458 					error = s_write(sc->indir, secno, uc);
459 			} else {
460 				if (osp <= 255) {
461 					sp = (uintptr_t)uma_zalloc(sc->uma,
462 					    md_malloc_wait ? M_WAITOK :
463 					    M_NOWAIT);
464 					if (sp == 0) {
465 						error = ENOSPC;
466 						break;
467 					}
468 					bcopy(dst, (void *)sp, sc->sectorsize);
469 					error = s_write(sc->indir, secno, sp);
470 				} else {
471 					bcopy(dst, (void *)osp, sc->sectorsize);
472 					osp = 0;
473 				}
474 			}
475 		} else {
476 			error = EOPNOTSUPP;
477 		}
478 		if (osp > 255)
479 			uma_zfree(sc->uma, (void*)osp);
480 		if (error != 0)
481 			break;
482 		secno++;
483 		dst += sc->sectorsize;
484 	}
485 	bp->bio_resid = 0;
486 	return (error);
487 }
488 
489 static int
490 mdstart_preload(struct md_s *sc, struct bio *bp)
491 {
492 
493 	switch (bp->bio_cmd) {
494 	case BIO_READ:
495 		bcopy(sc->pl_ptr + bp->bio_offset, bp->bio_data,
496 		    bp->bio_length);
497 		cpu_flush_dcache(bp->bio_data, bp->bio_length);
498 		break;
499 	case BIO_WRITE:
500 		bcopy(bp->bio_data, sc->pl_ptr + bp->bio_offset,
501 		    bp->bio_length);
502 		break;
503 	}
504 	bp->bio_resid = 0;
505 	return (0);
506 }
507 
508 static int
509 mdstart_vnode(struct md_s *sc, struct bio *bp)
510 {
511 	int error, vfslocked;
512 	struct uio auio;
513 	struct iovec aiov;
514 	struct mount *mp;
515 	struct vnode *vp;
516 	struct thread *td;
517 
518 	switch (bp->bio_cmd) {
519 	case BIO_READ:
520 	case BIO_WRITE:
521 	case BIO_FLUSH:
522 		break;
523 	default:
524 		return (EOPNOTSUPP);
525 	}
526 
527 	td = curthread;
528 	vp = sc->vnode;
529 
530 	/*
531 	 * VNODE I/O
532 	 *
533 	 * If an error occurs, we set BIO_ERROR but we do not set
534 	 * B_INVAL because (for a write anyway), the buffer is
535 	 * still valid.
536 	 */
537 
538 	if (bp->bio_cmd == BIO_FLUSH) {
539 		vfslocked = VFS_LOCK_GIANT(vp->v_mount);
540 		(void) vn_start_write(vp, &mp, V_WAIT);
541 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
542 		error = VOP_FSYNC(vp, MNT_WAIT, td);
543 		VOP_UNLOCK(vp, 0);
544 		vn_finished_write(mp);
545 		VFS_UNLOCK_GIANT(vfslocked);
546 		return (error);
547 	}
548 
549 	bzero(&auio, sizeof(auio));
550 
551 	aiov.iov_base = bp->bio_data;
552 	aiov.iov_len = bp->bio_length;
553 	auio.uio_iov = &aiov;
554 	auio.uio_iovcnt = 1;
555 	auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
556 	auio.uio_segflg = UIO_SYSSPACE;
557 	if (bp->bio_cmd == BIO_READ)
558 		auio.uio_rw = UIO_READ;
559 	else if (bp->bio_cmd == BIO_WRITE)
560 		auio.uio_rw = UIO_WRITE;
561 	else
562 		panic("wrong BIO_OP in mdstart_vnode");
563 	auio.uio_resid = bp->bio_length;
564 	auio.uio_td = td;
565 	/*
566 	 * When reading set IO_DIRECT to try to avoid double-caching
567 	 * the data.  When writing IO_DIRECT is not optimal.
568 	 */
569 	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
570 	if (bp->bio_cmd == BIO_READ) {
571 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
572 		error = VOP_READ(vp, &auio, IO_DIRECT, sc->cred);
573 		VOP_UNLOCK(vp, 0);
574 	} else {
575 		(void) vn_start_write(vp, &mp, V_WAIT);
576 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
577 		error = VOP_WRITE(vp, &auio, sc->flags & MD_ASYNC ? 0 : IO_SYNC,
578 		    sc->cred);
579 		VOP_UNLOCK(vp, 0);
580 		vn_finished_write(mp);
581 	}
582 	VFS_UNLOCK_GIANT(vfslocked);
583 	bp->bio_resid = auio.uio_resid;
584 	return (error);
585 }
586 
587 static int
588 mdstart_swap(struct md_s *sc, struct bio *bp)
589 {
590 	struct sf_buf *sf;
591 	int rv, offs, len, lastend;
592 	vm_pindex_t i, lastp;
593 	vm_page_t m;
594 	u_char *p;
595 
596 	switch (bp->bio_cmd) {
597 	case BIO_READ:
598 	case BIO_WRITE:
599 	case BIO_DELETE:
600 		break;
601 	default:
602 		return (EOPNOTSUPP);
603 	}
604 
605 	p = bp->bio_data;
606 
607 	/*
608 	 * offs is the offset at which to start operating on the
609 	 * next (ie, first) page.  lastp is the last page on
610 	 * which we're going to operate.  lastend is the ending
611 	 * position within that last page (ie, PAGE_SIZE if
612 	 * we're operating on complete aligned pages).
613 	 */
614 	offs = bp->bio_offset % PAGE_SIZE;
615 	lastp = (bp->bio_offset + bp->bio_length - 1) / PAGE_SIZE;
616 	lastend = (bp->bio_offset + bp->bio_length - 1) % PAGE_SIZE + 1;
617 
618 	rv = VM_PAGER_OK;
619 	VM_OBJECT_LOCK(sc->object);
620 	vm_object_pip_add(sc->object, 1);
621 	for (i = bp->bio_offset / PAGE_SIZE; i <= lastp; i++) {
622 		len = ((i == lastp) ? lastend : PAGE_SIZE) - offs;
623 
624 		m = vm_page_grab(sc->object, i,
625 		    VM_ALLOC_NORMAL|VM_ALLOC_RETRY);
626 		VM_OBJECT_UNLOCK(sc->object);
627 		sched_pin();
628 		sf = sf_buf_alloc(m, SFB_CPUPRIVATE);
629 		VM_OBJECT_LOCK(sc->object);
630 		if (bp->bio_cmd == BIO_READ) {
631 			if (m->valid != VM_PAGE_BITS_ALL)
632 				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
633 			if (rv == VM_PAGER_ERROR) {
634 				sf_buf_free(sf);
635 				sched_unpin();
636 				vm_page_wakeup(m);
637 				break;
638 			}
639 			bcopy((void *)(sf_buf_kva(sf) + offs), p, len);
640 			cpu_flush_dcache(p, len);
641 		} else if (bp->bio_cmd == BIO_WRITE) {
642 			if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
643 				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
644 			if (rv == VM_PAGER_ERROR) {
645 				sf_buf_free(sf);
646 				sched_unpin();
647 				vm_page_wakeup(m);
648 				break;
649 			}
650 			bcopy(p, (void *)(sf_buf_kva(sf) + offs), len);
651 			m->valid = VM_PAGE_BITS_ALL;
652 		} else if (bp->bio_cmd == BIO_DELETE) {
653 			if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
654 				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
655 			if (rv == VM_PAGER_ERROR) {
656 				sf_buf_free(sf);
657 				sched_unpin();
658 				vm_page_wakeup(m);
659 				break;
660 			}
661 			if (len != PAGE_SIZE) {
662 				bzero((void *)(sf_buf_kva(sf) + offs), len);
663 				vm_page_clear_dirty(m, offs, len);
664 				m->valid = VM_PAGE_BITS_ALL;
665 			} else
666 				vm_pager_page_unswapped(m);
667 		}
668 		sf_buf_free(sf);
669 		sched_unpin();
670 		vm_page_wakeup(m);
671 		vm_page_lock(m);
672 		if (bp->bio_cmd == BIO_DELETE && len == PAGE_SIZE)
673 			vm_page_free(m);
674 		else
675 			vm_page_activate(m);
676 		vm_page_unlock(m);
677 		if (bp->bio_cmd == BIO_WRITE)
678 			vm_page_dirty(m);
679 
680 		/* Actions on further pages start at offset 0 */
681 		p += PAGE_SIZE - offs;
682 		offs = 0;
683 #if 0
684 if (bootverbose || bp->bio_offset / PAGE_SIZE < 17)
685 printf("wire_count %d busy %d flags %x hold_count %d act_count %d queue %d valid %d dirty %d @ %d\n",
686     m->wire_count, m->busy,
687     m->flags, m->hold_count, m->act_count, m->queue, m->valid, m->dirty, i);
688 #endif
689 	}
690 	vm_object_pip_subtract(sc->object, 1);
691 	VM_OBJECT_UNLOCK(sc->object);
692 	return (rv != VM_PAGER_ERROR ? 0 : ENOSPC);
693 }
694 
695 static void
696 md_kthread(void *arg)
697 {
698 	struct md_s *sc;
699 	struct bio *bp;
700 	int error;
701 
702 	sc = arg;
703 	thread_lock(curthread);
704 	sched_prio(curthread, PRIBIO);
705 	thread_unlock(curthread);
706 	if (sc->type == MD_VNODE)
707 		curthread->td_pflags |= TDP_NORUNNINGBUF;
708 
709 	for (;;) {
710 		mtx_lock(&sc->queue_mtx);
711 		if (sc->flags & MD_SHUTDOWN) {
712 			sc->flags |= MD_EXITING;
713 			mtx_unlock(&sc->queue_mtx);
714 			kproc_exit(0);
715 		}
716 		bp = bioq_takefirst(&sc->bio_queue);
717 		if (!bp) {
718 			msleep(sc, &sc->queue_mtx, PRIBIO | PDROP, "mdwait", 0);
719 			continue;
720 		}
721 		mtx_unlock(&sc->queue_mtx);
722 		if (bp->bio_cmd == BIO_GETATTR) {
723 			if ((sc->fwsectors && sc->fwheads &&
724 			    (g_handleattr_int(bp, "GEOM::fwsectors",
725 			    sc->fwsectors) ||
726 			    g_handleattr_int(bp, "GEOM::fwheads",
727 			    sc->fwheads))) ||
728 			    g_handleattr_int(bp, "GEOM::candelete", 1))
729 				error = -1;
730 			else
731 				error = EOPNOTSUPP;
732 		} else {
733 			error = sc->start(sc, bp);
734 		}
735 
736 		if (error != -1) {
737 			bp->bio_completed = bp->bio_length;
738 			if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
739 				devstat_end_transaction_bio(sc->devstat, bp);
740 			g_io_deliver(bp, error);
741 		}
742 	}
743 }
744 
745 static struct md_s *
746 mdfind(int unit)
747 {
748 	struct md_s *sc;
749 
750 	LIST_FOREACH(sc, &md_softc_list, list) {
751 		if (sc->unit == unit)
752 			break;
753 	}
754 	return (sc);
755 }
756 
757 static struct md_s *
758 mdnew(int unit, int *errp, enum md_types type)
759 {
760 	struct md_s *sc;
761 	int error;
762 
763 	*errp = 0;
764 	if (unit == -1)
765 		unit = alloc_unr(md_uh);
766 	else
767 		unit = alloc_unr_specific(md_uh, unit);
768 
769 	if (unit == -1) {
770 		*errp = EBUSY;
771 		return (NULL);
772 	}
773 
774 	sc = (struct md_s *)malloc(sizeof *sc, M_MD, M_WAITOK | M_ZERO);
775 	sc->type = type;
776 	bioq_init(&sc->bio_queue);
777 	mtx_init(&sc->queue_mtx, "md bio queue", NULL, MTX_DEF);
778 	sc->unit = unit;
779 	sprintf(sc->name, "md%d", unit);
780 	LIST_INSERT_HEAD(&md_softc_list, sc, list);
781 	error = kproc_create(md_kthread, sc, &sc->procp, 0, 0,"%s", sc->name);
782 	if (error == 0)
783 		return (sc);
784 	LIST_REMOVE(sc, list);
785 	mtx_destroy(&sc->queue_mtx);
786 	free_unr(md_uh, sc->unit);
787 	free(sc, M_MD);
788 	*errp = error;
789 	return (NULL);
790 }
791 
792 static void
793 mdinit(struct md_s *sc)
794 {
795 	struct g_geom *gp;
796 	struct g_provider *pp;
797 
798 	g_topology_lock();
799 	gp = g_new_geomf(&g_md_class, "md%d", sc->unit);
800 	gp->softc = sc;
801 	pp = g_new_providerf(gp, "md%d", sc->unit);
802 	pp->mediasize = sc->mediasize;
803 	pp->sectorsize = sc->sectorsize;
804 	sc->gp = gp;
805 	sc->pp = pp;
806 	g_error_provider(pp, 0);
807 	g_topology_unlock();
808 	sc->devstat = devstat_new_entry("md", sc->unit, sc->sectorsize,
809 	    DEVSTAT_ALL_SUPPORTED, DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
810 }
811 
812 /*
813  * XXX: we should check that the range they feed us is mapped.
814  * XXX: we should implement read-only.
815  */
816 
817 static int
818 mdcreate_preload(struct md_s *sc, struct md_ioctl *mdio)
819 {
820 
821 	if (mdio->md_options & ~(MD_AUTOUNIT | MD_FORCE))
822 		return (EINVAL);
823 	if (mdio->md_base == 0)
824 		return (EINVAL);
825 	sc->flags = mdio->md_options & MD_FORCE;
826 	/* Cast to pointer size, then to pointer to avoid warning */
827 	sc->pl_ptr = (u_char *)(uintptr_t)mdio->md_base;
828 	sc->pl_len = (size_t)sc->mediasize;
829 	return (0);
830 }
831 
832 
833 static int
834 mdcreate_malloc(struct md_s *sc, struct md_ioctl *mdio)
835 {
836 	uintptr_t sp;
837 	int error;
838 	off_t u;
839 
840 	error = 0;
841 	if (mdio->md_options & ~(MD_AUTOUNIT | MD_COMPRESS | MD_RESERVE))
842 		return (EINVAL);
843 	if (mdio->md_sectorsize != 0 && !powerof2(mdio->md_sectorsize))
844 		return (EINVAL);
845 	/* Compression doesn't make sense if we have reserved space */
846 	if (mdio->md_options & MD_RESERVE)
847 		mdio->md_options &= ~MD_COMPRESS;
848 	if (mdio->md_fwsectors != 0)
849 		sc->fwsectors = mdio->md_fwsectors;
850 	if (mdio->md_fwheads != 0)
851 		sc->fwheads = mdio->md_fwheads;
852 	sc->flags = mdio->md_options & (MD_COMPRESS | MD_FORCE);
853 	sc->indir = dimension(sc->mediasize / sc->sectorsize);
854 	sc->uma = uma_zcreate(sc->name, sc->sectorsize, NULL, NULL, NULL, NULL,
855 	    0x1ff, 0);
856 	if (mdio->md_options & MD_RESERVE) {
857 		off_t nsectors;
858 
859 		nsectors = sc->mediasize / sc->sectorsize;
860 		for (u = 0; u < nsectors; u++) {
861 			sp = (uintptr_t)uma_zalloc(sc->uma, (md_malloc_wait ?
862 			    M_WAITOK : M_NOWAIT) | M_ZERO);
863 			if (sp != 0)
864 				error = s_write(sc->indir, u, sp);
865 			else
866 				error = ENOMEM;
867 			if (error != 0)
868 				break;
869 		}
870 	}
871 	return (error);
872 }
873 
874 
875 static int
876 mdsetcred(struct md_s *sc, struct ucred *cred)
877 {
878 	char *tmpbuf;
879 	int error = 0;
880 
881 	/*
882 	 * Set credits in our softc
883 	 */
884 
885 	if (sc->cred)
886 		crfree(sc->cred);
887 	sc->cred = crhold(cred);
888 
889 	/*
890 	 * Horrible kludge to establish credentials for NFS  XXX.
891 	 */
892 
893 	if (sc->vnode) {
894 		struct uio auio;
895 		struct iovec aiov;
896 
897 		tmpbuf = malloc(sc->sectorsize, M_TEMP, M_WAITOK);
898 		bzero(&auio, sizeof(auio));
899 
900 		aiov.iov_base = tmpbuf;
901 		aiov.iov_len = sc->sectorsize;
902 		auio.uio_iov = &aiov;
903 		auio.uio_iovcnt = 1;
904 		auio.uio_offset = 0;
905 		auio.uio_rw = UIO_READ;
906 		auio.uio_segflg = UIO_SYSSPACE;
907 		auio.uio_resid = aiov.iov_len;
908 		vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY);
909 		error = VOP_READ(sc->vnode, &auio, 0, sc->cred);
910 		VOP_UNLOCK(sc->vnode, 0);
911 		free(tmpbuf, M_TEMP);
912 	}
913 	return (error);
914 }
915 
916 static int
917 mdcreate_vnode(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
918 {
919 	struct vattr vattr;
920 	struct nameidata nd;
921 	char *fname;
922 	int error, flags, vfslocked;
923 
924 	/*
925 	 * Kernel-originated requests must have the filename appended
926 	 * to the mdio structure to protect against malicious software.
927 	 */
928 	fname = mdio->md_file;
929 	if ((void *)fname != (void *)(mdio + 1)) {
930 		error = copyinstr(fname, sc->file, sizeof(sc->file), NULL);
931 		if (error != 0)
932 			return (error);
933 	} else
934 		strlcpy(sc->file, fname, sizeof(sc->file));
935 
936 	/*
937 	 * If the user specified that this is a read only device, don't
938 	 * set the FWRITE mask before trying to open the backing store.
939 	 */
940 	flags = FREAD | ((mdio->md_options & MD_READONLY) ? 0 : FWRITE);
941 	NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, sc->file, td);
942 	error = vn_open(&nd, &flags, 0, NULL);
943 	if (error != 0)
944 		return (error);
945 	vfslocked = NDHASGIANT(&nd);
946 	NDFREE(&nd, NDF_ONLY_PNBUF);
947 	if (nd.ni_vp->v_type != VREG) {
948 		error = EINVAL;
949 		goto bad;
950 	}
951 	error = VOP_GETATTR(nd.ni_vp, &vattr, td->td_ucred);
952 	if (error != 0)
953 		goto bad;
954 	if (VOP_ISLOCKED(nd.ni_vp) != LK_EXCLUSIVE) {
955 		vn_lock(nd.ni_vp, LK_UPGRADE | LK_RETRY);
956 		if (nd.ni_vp->v_iflag & VI_DOOMED) {
957 			/* Forced unmount. */
958 			error = EBADF;
959 			goto bad;
960 		}
961 	}
962 	nd.ni_vp->v_vflag |= VV_MD;
963 	VOP_UNLOCK(nd.ni_vp, 0);
964 
965 	if (mdio->md_fwsectors != 0)
966 		sc->fwsectors = mdio->md_fwsectors;
967 	if (mdio->md_fwheads != 0)
968 		sc->fwheads = mdio->md_fwheads;
969 	sc->flags = mdio->md_options & (MD_FORCE | MD_ASYNC);
970 	if (!(flags & FWRITE))
971 		sc->flags |= MD_READONLY;
972 	sc->vnode = nd.ni_vp;
973 
974 	error = mdsetcred(sc, td->td_ucred);
975 	if (error != 0) {
976 		sc->vnode = NULL;
977 		vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
978 		nd.ni_vp->v_vflag &= ~VV_MD;
979 		goto bad;
980 	}
981 	VFS_UNLOCK_GIANT(vfslocked);
982 	return (0);
983 bad:
984 	VOP_UNLOCK(nd.ni_vp, 0);
985 	(void)vn_close(nd.ni_vp, flags, td->td_ucred, td);
986 	VFS_UNLOCK_GIANT(vfslocked);
987 	return (error);
988 }
989 
990 static int
991 mddestroy(struct md_s *sc, struct thread *td)
992 {
993 	int vfslocked;
994 
995 	if (sc->gp) {
996 		sc->gp->softc = NULL;
997 		g_topology_lock();
998 		g_wither_geom(sc->gp, ENXIO);
999 		g_topology_unlock();
1000 		sc->gp = NULL;
1001 		sc->pp = NULL;
1002 	}
1003 	if (sc->devstat) {
1004 		devstat_remove_entry(sc->devstat);
1005 		sc->devstat = NULL;
1006 	}
1007 	mtx_lock(&sc->queue_mtx);
1008 	sc->flags |= MD_SHUTDOWN;
1009 	wakeup(sc);
1010 	while (!(sc->flags & MD_EXITING))
1011 		msleep(sc->procp, &sc->queue_mtx, PRIBIO, "mddestroy", hz / 10);
1012 	mtx_unlock(&sc->queue_mtx);
1013 	mtx_destroy(&sc->queue_mtx);
1014 	if (sc->vnode != NULL) {
1015 		vfslocked = VFS_LOCK_GIANT(sc->vnode->v_mount);
1016 		vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY);
1017 		sc->vnode->v_vflag &= ~VV_MD;
1018 		VOP_UNLOCK(sc->vnode, 0);
1019 		(void)vn_close(sc->vnode, sc->flags & MD_READONLY ?
1020 		    FREAD : (FREAD|FWRITE), sc->cred, td);
1021 		VFS_UNLOCK_GIANT(vfslocked);
1022 	}
1023 	if (sc->cred != NULL)
1024 		crfree(sc->cred);
1025 	if (sc->object != NULL)
1026 		vm_object_deallocate(sc->object);
1027 	if (sc->indir)
1028 		destroy_indir(sc, sc->indir);
1029 	if (sc->uma)
1030 		uma_zdestroy(sc->uma);
1031 
1032 	LIST_REMOVE(sc, list);
1033 	free_unr(md_uh, sc->unit);
1034 	free(sc, M_MD);
1035 	return (0);
1036 }
1037 
1038 static int
1039 mdcreate_swap(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
1040 {
1041 	vm_ooffset_t npage;
1042 	int error;
1043 
1044 	/*
1045 	 * Range check.  Disallow negative sizes or any size less then the
1046 	 * size of a page.  Then round to a page.
1047 	 */
1048 	if (sc->mediasize == 0 || (sc->mediasize % PAGE_SIZE) != 0)
1049 		return (EDOM);
1050 
1051 	/*
1052 	 * Allocate an OBJT_SWAP object.
1053 	 *
1054 	 * Note the truncation.
1055 	 */
1056 
1057 	npage = mdio->md_mediasize / PAGE_SIZE;
1058 	if (mdio->md_fwsectors != 0)
1059 		sc->fwsectors = mdio->md_fwsectors;
1060 	if (mdio->md_fwheads != 0)
1061 		sc->fwheads = mdio->md_fwheads;
1062 	sc->object = vm_pager_allocate(OBJT_SWAP, NULL, PAGE_SIZE * npage,
1063 	    VM_PROT_DEFAULT, 0, td->td_ucred);
1064 	if (sc->object == NULL)
1065 		return (ENOMEM);
1066 	sc->flags = mdio->md_options & MD_FORCE;
1067 	if (mdio->md_options & MD_RESERVE) {
1068 		if (swap_pager_reserve(sc->object, 0, npage) < 0) {
1069 			error = EDOM;
1070 			goto finish;
1071 		}
1072 	}
1073 	error = mdsetcred(sc, td->td_ucred);
1074  finish:
1075 	if (error != 0) {
1076 		vm_object_deallocate(sc->object);
1077 		sc->object = NULL;
1078 	}
1079 	return (error);
1080 }
1081 
1082 
1083 static int
1084 xmdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
1085 {
1086 	struct md_ioctl *mdio;
1087 	struct md_s *sc;
1088 	int error, i;
1089 
1090 	if (md_debug)
1091 		printf("mdctlioctl(%s %lx %p %x %p)\n",
1092 			devtoname(dev), cmd, addr, flags, td);
1093 
1094 	mdio = (struct md_ioctl *)addr;
1095 	if (mdio->md_version != MDIOVERSION)
1096 		return (EINVAL);
1097 
1098 	/*
1099 	 * We assert the version number in the individual ioctl
1100 	 * handlers instead of out here because (a) it is possible we
1101 	 * may add another ioctl in the future which doesn't read an
1102 	 * mdio, and (b) the correct return value for an unknown ioctl
1103 	 * is ENOIOCTL, not EINVAL.
1104 	 */
1105 	error = 0;
1106 	switch (cmd) {
1107 	case MDIOCATTACH:
1108 		switch (mdio->md_type) {
1109 		case MD_MALLOC:
1110 		case MD_PRELOAD:
1111 		case MD_VNODE:
1112 		case MD_SWAP:
1113 			break;
1114 		default:
1115 			return (EINVAL);
1116 		}
1117 		if (mdio->md_options & MD_AUTOUNIT)
1118 			sc = mdnew(-1, &error, mdio->md_type);
1119 		else {
1120 			if (mdio->md_unit > INT_MAX)
1121 				return (EINVAL);
1122 			sc = mdnew(mdio->md_unit, &error, mdio->md_type);
1123 		}
1124 		if (sc == NULL)
1125 			return (error);
1126 		if (mdio->md_options & MD_AUTOUNIT)
1127 			mdio->md_unit = sc->unit;
1128 		sc->mediasize = mdio->md_mediasize;
1129 		if (mdio->md_sectorsize == 0)
1130 			sc->sectorsize = DEV_BSIZE;
1131 		else
1132 			sc->sectorsize = mdio->md_sectorsize;
1133 		error = EDOOFUS;
1134 		switch (sc->type) {
1135 		case MD_MALLOC:
1136 			sc->start = mdstart_malloc;
1137 			error = mdcreate_malloc(sc, mdio);
1138 			break;
1139 		case MD_PRELOAD:
1140 			sc->start = mdstart_preload;
1141 			error = mdcreate_preload(sc, mdio);
1142 			break;
1143 		case MD_VNODE:
1144 			sc->start = mdstart_vnode;
1145 			error = mdcreate_vnode(sc, mdio, td);
1146 			break;
1147 		case MD_SWAP:
1148 			sc->start = mdstart_swap;
1149 			error = mdcreate_swap(sc, mdio, td);
1150 			break;
1151 		}
1152 		if (error != 0) {
1153 			mddestroy(sc, td);
1154 			return (error);
1155 		}
1156 
1157 		/* Prune off any residual fractional sector */
1158 		i = sc->mediasize % sc->sectorsize;
1159 		sc->mediasize -= i;
1160 
1161 		mdinit(sc);
1162 		return (0);
1163 	case MDIOCDETACH:
1164 		if (mdio->md_mediasize != 0 ||
1165 		    (mdio->md_options & ~MD_FORCE) != 0)
1166 			return (EINVAL);
1167 
1168 		sc = mdfind(mdio->md_unit);
1169 		if (sc == NULL)
1170 			return (ENOENT);
1171 		if (sc->opencount != 0 && !(sc->flags & MD_FORCE) &&
1172 		    !(mdio->md_options & MD_FORCE))
1173 			return (EBUSY);
1174 		return (mddestroy(sc, td));
1175 	case MDIOCQUERY:
1176 		sc = mdfind(mdio->md_unit);
1177 		if (sc == NULL)
1178 			return (ENOENT);
1179 		mdio->md_type = sc->type;
1180 		mdio->md_options = sc->flags;
1181 		mdio->md_mediasize = sc->mediasize;
1182 		mdio->md_sectorsize = sc->sectorsize;
1183 		if (sc->type == MD_VNODE)
1184 			error = copyout(sc->file, mdio->md_file,
1185 			    strlen(sc->file) + 1);
1186 		return (error);
1187 	case MDIOCLIST:
1188 		i = 1;
1189 		LIST_FOREACH(sc, &md_softc_list, list) {
1190 			if (i == MDNPAD - 1)
1191 				mdio->md_pad[i] = -1;
1192 			else
1193 				mdio->md_pad[i++] = sc->unit;
1194 		}
1195 		mdio->md_pad[0] = i - 1;
1196 		return (0);
1197 	default:
1198 		return (ENOIOCTL);
1199 	};
1200 }
1201 
1202 static int
1203 mdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
1204 {
1205 	int error;
1206 
1207 	sx_xlock(&md_sx);
1208 	error = xmdctlioctl(dev, cmd, addr, flags, td);
1209 	sx_xunlock(&md_sx);
1210 	return (error);
1211 }
1212 
1213 static void
1214 md_preloaded(u_char *image, size_t length)
1215 {
1216 	struct md_s *sc;
1217 	int error;
1218 
1219 	sc = mdnew(-1, &error, MD_PRELOAD);
1220 	if (sc == NULL)
1221 		return;
1222 	sc->mediasize = length;
1223 	sc->sectorsize = DEV_BSIZE;
1224 	sc->pl_ptr = image;
1225 	sc->pl_len = length;
1226 	sc->start = mdstart_preload;
1227 #ifdef MD_ROOT
1228 	if (sc->unit == 0)
1229 		rootdevnames[0] = "ufs:/dev/md0";
1230 #endif
1231 	mdinit(sc);
1232 }
1233 
1234 static void
1235 g_md_init(struct g_class *mp __unused)
1236 {
1237 	caddr_t mod;
1238 	u_char *ptr, *name, *type;
1239 	unsigned len;
1240 	int i;
1241 
1242 	/* figure out log2(NINDIR) */
1243 	for (i = NINDIR, nshift = -1; i; nshift++)
1244 		i >>= 1;
1245 
1246 	mod = NULL;
1247 	sx_init(&md_sx, "MD config lock");
1248 	g_topology_unlock();
1249 	md_uh = new_unrhdr(0, INT_MAX, NULL);
1250 #ifdef MD_ROOT_SIZE
1251 	sx_xlock(&md_sx);
1252 	md_preloaded(mfs_root.start, sizeof(mfs_root.start));
1253 	sx_xunlock(&md_sx);
1254 #endif
1255 	/* XXX: are preload_* static or do they need Giant ? */
1256 	while ((mod = preload_search_next_name(mod)) != NULL) {
1257 		name = (char *)preload_search_info(mod, MODINFO_NAME);
1258 		if (name == NULL)
1259 			continue;
1260 		type = (char *)preload_search_info(mod, MODINFO_TYPE);
1261 		if (type == NULL)
1262 			continue;
1263 		if (strcmp(type, "md_image") && strcmp(type, "mfs_root"))
1264 			continue;
1265 		ptr = preload_fetch_addr(mod);
1266 		len = preload_fetch_size(mod);
1267 		if (ptr != NULL && len != 0) {
1268 			printf("%s%d: Preloaded image <%s> %d bytes at %p\n",
1269 			    MD_NAME, mdunits, name, len, ptr);
1270 			sx_xlock(&md_sx);
1271 			md_preloaded(ptr, len);
1272 			sx_xunlock(&md_sx);
1273 		}
1274 	}
1275 	status_dev = make_dev(&mdctl_cdevsw, INT_MAX, UID_ROOT, GID_WHEEL,
1276 	    0600, MDCTL_NAME);
1277 	g_topology_lock();
1278 }
1279 
1280 static void
1281 g_md_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1282     struct g_consumer *cp __unused, struct g_provider *pp)
1283 {
1284 	struct md_s *mp;
1285 	char *type;
1286 
1287 	mp = gp->softc;
1288 	if (mp == NULL)
1289 		return;
1290 
1291 	switch (mp->type) {
1292 	case MD_MALLOC:
1293 		type = "malloc";
1294 		break;
1295 	case MD_PRELOAD:
1296 		type = "preload";
1297 		break;
1298 	case MD_VNODE:
1299 		type = "vnode";
1300 		break;
1301 	case MD_SWAP:
1302 		type = "swap";
1303 		break;
1304 	default:
1305 		type = "unknown";
1306 		break;
1307 	}
1308 
1309 	if (pp != NULL) {
1310 		if (indent == NULL) {
1311 			sbuf_printf(sb, " u %d", mp->unit);
1312 			sbuf_printf(sb, " s %ju", (uintmax_t) mp->sectorsize);
1313 			sbuf_printf(sb, " f %ju", (uintmax_t) mp->fwheads);
1314 			sbuf_printf(sb, " fs %ju", (uintmax_t) mp->fwsectors);
1315 			sbuf_printf(sb, " l %ju", (uintmax_t) mp->mediasize);
1316 			sbuf_printf(sb, " t %s", type);
1317 			if (mp->type == MD_VNODE && mp->vnode != NULL)
1318 				sbuf_printf(sb, " file %s", mp->file);
1319 		} else {
1320 			sbuf_printf(sb, "%s<unit>%d</unit>\n", indent,
1321 			    mp->unit);
1322 			sbuf_printf(sb, "%s<sectorsize>%ju</sectorsize>\n",
1323 			    indent, (uintmax_t) mp->sectorsize);
1324 			sbuf_printf(sb, "%s<fwheads>%ju</fwheads>\n",
1325 			    indent, (uintmax_t) mp->fwheads);
1326 			sbuf_printf(sb, "%s<fwsectors>%ju</fwsectors>\n",
1327 			    indent, (uintmax_t) mp->fwsectors);
1328 			sbuf_printf(sb, "%s<length>%ju</length>\n",
1329 			    indent, (uintmax_t) mp->mediasize);
1330 			sbuf_printf(sb, "%s<type>%s</type>\n", indent,
1331 			    type);
1332 			if (mp->type == MD_VNODE && mp->vnode != NULL)
1333 				sbuf_printf(sb, "%s<file>%s</file>\n",
1334 				    indent, mp->file);
1335 		}
1336 	}
1337 }
1338 
1339 static void
1340 g_md_fini(struct g_class *mp __unused)
1341 {
1342 
1343 	sx_destroy(&md_sx);
1344 	if (status_dev != NULL)
1345 		destroy_dev(status_dev);
1346 	delete_unrhdr(md_uh);
1347 }
1348