md.c revision 223920
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: head/sys/dev/md/md.c 223920 2011-07-11 05:19:28Z ae $
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/sbuf.h>
79#include <sys/sched.h>
80#include <sys/sf_buf.h>
81#include <sys/sysctl.h>
82#include <sys/vnode.h>
83
84#include <geom/geom.h>
85
86#include <vm/vm.h>
87#include <vm/vm_object.h>
88#include <vm/vm_page.h>
89#include <vm/vm_pager.h>
90#include <vm/swap_pager.h>
91#include <vm/uma.h>
92
93#include <machine/vmparam.h>
94
95#define MD_MODVER 1
96
97#define MD_SHUTDOWN	0x10000		/* Tell worker thread to terminate. */
98#define	MD_EXITING	0x20000		/* Worker thread is exiting. */
99
100#ifndef MD_NSECT
101#define MD_NSECT (10000 * 2)
102#endif
103
104static MALLOC_DEFINE(M_MD, "md_disk", "Memory Disk");
105static MALLOC_DEFINE(M_MDSECT, "md_sectors", "Memory Disk Sectors");
106
107static int md_debug;
108SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0, "");
109static int md_malloc_wait;
110SYSCTL_INT(_vm, OID_AUTO, md_malloc_wait, CTLFLAG_RW, &md_malloc_wait, 0, "");
111
112#if defined(MD_ROOT) && defined(MD_ROOT_SIZE)
113/*
114 * Preloaded image gets put here.
115 * Applications that patch the object with the image can determine
116 * the size looking at the start and end markers (strings),
117 * so we want them contiguous.
118 */
119static struct {
120	u_char start[MD_ROOT_SIZE*1024];
121	u_char end[128];
122} mfs_root = {
123	.start = "MFS Filesystem goes here",
124	.end = "MFS Filesystem had better STOP here",
125};
126#endif
127
128static g_init_t g_md_init;
129static g_fini_t g_md_fini;
130static g_start_t g_md_start;
131static g_access_t g_md_access;
132static void g_md_dumpconf(struct sbuf *sb, const char *indent,
133    struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp);
134
135static int mdunits;
136static struct cdev *status_dev = 0;
137static struct sx md_sx;
138static struct unrhdr *md_uh;
139
140static d_ioctl_t mdctlioctl;
141
142static struct cdevsw mdctl_cdevsw = {
143	.d_version =	D_VERSION,
144	.d_ioctl =	mdctlioctl,
145	.d_name =	MD_NAME,
146};
147
148struct g_class g_md_class = {
149	.name = "MD",
150	.version = G_VERSION,
151	.init = g_md_init,
152	.fini = g_md_fini,
153	.start = g_md_start,
154	.access = g_md_access,
155	.dumpconf = g_md_dumpconf,
156};
157
158DECLARE_GEOM_CLASS(g_md_class, g_md);
159
160
161static LIST_HEAD(, md_s) md_softc_list = LIST_HEAD_INITIALIZER(md_softc_list);
162
163#define NINDIR	(PAGE_SIZE / sizeof(uintptr_t))
164#define NMASK	(NINDIR-1)
165static int nshift;
166
167struct indir {
168	uintptr_t	*array;
169	u_int		total;
170	u_int		used;
171	u_int		shift;
172};
173
174struct md_s {
175	int unit;
176	LIST_ENTRY(md_s) list;
177	struct bio_queue_head bio_queue;
178	struct mtx queue_mtx;
179	struct cdev *dev;
180	enum md_types type;
181	off_t mediasize;
182	unsigned sectorsize;
183	unsigned opencount;
184	unsigned fwheads;
185	unsigned fwsectors;
186	unsigned flags;
187	char name[20];
188	struct proc *procp;
189	struct g_geom *gp;
190	struct g_provider *pp;
191	int (*start)(struct md_s *sc, struct bio *bp);
192	struct devstat *devstat;
193
194	/* MD_MALLOC related fields */
195	struct indir *indir;
196	uma_zone_t uma;
197
198	/* MD_PRELOAD related fields */
199	u_char *pl_ptr;
200	size_t pl_len;
201
202	/* MD_VNODE related fields */
203	struct vnode *vnode;
204	char file[PATH_MAX];
205	struct ucred *cred;
206
207	/* MD_SWAP related fields */
208	vm_object_t object;
209};
210
211static struct indir *
212new_indir(u_int shift)
213{
214	struct indir *ip;
215
216	ip = malloc(sizeof *ip, M_MD, (md_malloc_wait ? M_WAITOK : M_NOWAIT)
217	    | M_ZERO);
218	if (ip == NULL)
219		return (NULL);
220	ip->array = malloc(sizeof(uintptr_t) * NINDIR,
221	    M_MDSECT, (md_malloc_wait ? M_WAITOK : M_NOWAIT) | M_ZERO);
222	if (ip->array == NULL) {
223		free(ip, M_MD);
224		return (NULL);
225	}
226	ip->total = NINDIR;
227	ip->shift = shift;
228	return (ip);
229}
230
231static void
232del_indir(struct indir *ip)
233{
234
235	free(ip->array, M_MDSECT);
236	free(ip, M_MD);
237}
238
239static void
240destroy_indir(struct md_s *sc, struct indir *ip)
241{
242	int i;
243
244	for (i = 0; i < NINDIR; i++) {
245		if (!ip->array[i])
246			continue;
247		if (ip->shift)
248			destroy_indir(sc, (struct indir*)(ip->array[i]));
249		else if (ip->array[i] > 255)
250			uma_zfree(sc->uma, (void *)(ip->array[i]));
251	}
252	del_indir(ip);
253}
254
255/*
256 * This function does the math and allocates the top level "indir" structure
257 * for a device of "size" sectors.
258 */
259
260static struct indir *
261dimension(off_t size)
262{
263	off_t rcnt;
264	struct indir *ip;
265	int layer;
266
267	rcnt = size;
268	layer = 0;
269	while (rcnt > NINDIR) {
270		rcnt /= NINDIR;
271		layer++;
272	}
273
274	/*
275	 * XXX: the top layer is probably not fully populated, so we allocate
276	 * too much space for ip->array in here.
277	 */
278	ip = malloc(sizeof *ip, M_MD, M_WAITOK | M_ZERO);
279	ip->array = malloc(sizeof(uintptr_t) * NINDIR,
280	    M_MDSECT, M_WAITOK | M_ZERO);
281	ip->total = NINDIR;
282	ip->shift = layer * nshift;
283	return (ip);
284}
285
286/*
287 * Read a given sector
288 */
289
290static uintptr_t
291s_read(struct indir *ip, off_t offset)
292{
293	struct indir *cip;
294	int idx;
295	uintptr_t up;
296
297	if (md_debug > 1)
298		printf("s_read(%jd)\n", (intmax_t)offset);
299	up = 0;
300	for (cip = ip; cip != NULL;) {
301		if (cip->shift) {
302			idx = (offset >> cip->shift) & NMASK;
303			up = cip->array[idx];
304			cip = (struct indir *)up;
305			continue;
306		}
307		idx = offset & NMASK;
308		return (cip->array[idx]);
309	}
310	return (0);
311}
312
313/*
314 * Write a given sector, prune the tree if the value is 0
315 */
316
317static int
318s_write(struct indir *ip, off_t offset, uintptr_t ptr)
319{
320	struct indir *cip, *lip[10];
321	int idx, li;
322	uintptr_t up;
323
324	if (md_debug > 1)
325		printf("s_write(%jd, %p)\n", (intmax_t)offset, (void *)ptr);
326	up = 0;
327	li = 0;
328	cip = ip;
329	for (;;) {
330		lip[li++] = cip;
331		if (cip->shift) {
332			idx = (offset >> cip->shift) & NMASK;
333			up = cip->array[idx];
334			if (up != 0) {
335				cip = (struct indir *)up;
336				continue;
337			}
338			/* Allocate branch */
339			cip->array[idx] =
340			    (uintptr_t)new_indir(cip->shift - nshift);
341			if (cip->array[idx] == 0)
342				return (ENOSPC);
343			cip->used++;
344			up = cip->array[idx];
345			cip = (struct indir *)up;
346			continue;
347		}
348		/* leafnode */
349		idx = offset & NMASK;
350		up = cip->array[idx];
351		if (up != 0)
352			cip->used--;
353		cip->array[idx] = ptr;
354		if (ptr != 0)
355			cip->used++;
356		break;
357	}
358	if (cip->used != 0 || li == 1)
359		return (0);
360	li--;
361	while (cip->used == 0 && cip != ip) {
362		li--;
363		idx = (offset >> lip[li]->shift) & NMASK;
364		up = lip[li]->array[idx];
365		KASSERT(up == (uintptr_t)cip, ("md screwed up"));
366		del_indir(cip);
367		lip[li]->array[idx] = 0;
368		lip[li]->used--;
369		cip = lip[li];
370	}
371	return (0);
372}
373
374
375static int
376g_md_access(struct g_provider *pp, int r, int w, int e)
377{
378	struct md_s *sc;
379
380	sc = pp->geom->softc;
381	if (sc == NULL) {
382		if (r <= 0 && w <= 0 && e <= 0)
383			return (0);
384		return (ENXIO);
385	}
386	r += pp->acr;
387	w += pp->acw;
388	e += pp->ace;
389	if ((sc->flags & MD_READONLY) != 0 && w > 0)
390		return (EROFS);
391	if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
392		sc->opencount = 1;
393	} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
394		sc->opencount = 0;
395	}
396	return (0);
397}
398
399static void
400g_md_start(struct bio *bp)
401{
402	struct md_s *sc;
403
404	sc = bp->bio_to->geom->softc;
405	if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
406		devstat_start_transaction_bio(sc->devstat, bp);
407	mtx_lock(&sc->queue_mtx);
408	bioq_disksort(&sc->bio_queue, bp);
409	mtx_unlock(&sc->queue_mtx);
410	wakeup(sc);
411}
412
413static int
414mdstart_malloc(struct md_s *sc, struct bio *bp)
415{
416	int i, error;
417	u_char *dst;
418	off_t secno, nsec, uc;
419	uintptr_t sp, osp;
420
421	switch (bp->bio_cmd) {
422	case BIO_READ:
423	case BIO_WRITE:
424	case BIO_DELETE:
425		break;
426	default:
427		return (EOPNOTSUPP);
428	}
429
430	nsec = bp->bio_length / sc->sectorsize;
431	secno = bp->bio_offset / sc->sectorsize;
432	dst = bp->bio_data;
433	error = 0;
434	while (nsec--) {
435		osp = s_read(sc->indir, secno);
436		if (bp->bio_cmd == BIO_DELETE) {
437			if (osp != 0)
438				error = s_write(sc->indir, secno, 0);
439		} else if (bp->bio_cmd == BIO_READ) {
440			if (osp == 0)
441				bzero(dst, sc->sectorsize);
442			else if (osp <= 255)
443				memset(dst, osp, sc->sectorsize);
444			else {
445				bcopy((void *)osp, dst, sc->sectorsize);
446				cpu_flush_dcache(dst, sc->sectorsize);
447			}
448			osp = 0;
449		} else if (bp->bio_cmd == BIO_WRITE) {
450			if (sc->flags & MD_COMPRESS) {
451				uc = dst[0];
452				for (i = 1; i < sc->sectorsize; i++)
453					if (dst[i] != uc)
454						break;
455			} else {
456				i = 0;
457				uc = 0;
458			}
459			if (i == sc->sectorsize) {
460				if (osp != uc)
461					error = s_write(sc->indir, secno, uc);
462			} else {
463				if (osp <= 255) {
464					sp = (uintptr_t)uma_zalloc(sc->uma,
465					    md_malloc_wait ? M_WAITOK :
466					    M_NOWAIT);
467					if (sp == 0) {
468						error = ENOSPC;
469						break;
470					}
471					bcopy(dst, (void *)sp, sc->sectorsize);
472					error = s_write(sc->indir, secno, sp);
473				} else {
474					bcopy(dst, (void *)osp, sc->sectorsize);
475					osp = 0;
476				}
477			}
478		} else {
479			error = EOPNOTSUPP;
480		}
481		if (osp > 255)
482			uma_zfree(sc->uma, (void*)osp);
483		if (error != 0)
484			break;
485		secno++;
486		dst += sc->sectorsize;
487	}
488	bp->bio_resid = 0;
489	return (error);
490}
491
492static int
493mdstart_preload(struct md_s *sc, struct bio *bp)
494{
495
496	switch (bp->bio_cmd) {
497	case BIO_READ:
498		bcopy(sc->pl_ptr + bp->bio_offset, bp->bio_data,
499		    bp->bio_length);
500		cpu_flush_dcache(bp->bio_data, bp->bio_length);
501		break;
502	case BIO_WRITE:
503		bcopy(bp->bio_data, sc->pl_ptr + bp->bio_offset,
504		    bp->bio_length);
505		break;
506	}
507	bp->bio_resid = 0;
508	return (0);
509}
510
511static int
512mdstart_vnode(struct md_s *sc, struct bio *bp)
513{
514	int error, vfslocked;
515	struct uio auio;
516	struct iovec aiov;
517	struct mount *mp;
518	struct vnode *vp;
519	struct thread *td;
520	off_t end, zerosize;
521
522	switch (bp->bio_cmd) {
523	case BIO_READ:
524	case BIO_WRITE:
525	case BIO_DELETE:
526	case BIO_FLUSH:
527		break;
528	default:
529		return (EOPNOTSUPP);
530	}
531
532	td = curthread;
533	vp = sc->vnode;
534
535	/*
536	 * VNODE I/O
537	 *
538	 * If an error occurs, we set BIO_ERROR but we do not set
539	 * B_INVAL because (for a write anyway), the buffer is
540	 * still valid.
541	 */
542
543	if (bp->bio_cmd == BIO_FLUSH) {
544		vfslocked = VFS_LOCK_GIANT(vp->v_mount);
545		(void) vn_start_write(vp, &mp, V_WAIT);
546		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
547		error = VOP_FSYNC(vp, MNT_WAIT, td);
548		VOP_UNLOCK(vp, 0);
549		vn_finished_write(mp);
550		VFS_UNLOCK_GIANT(vfslocked);
551		return (error);
552	}
553
554	bzero(&auio, sizeof(auio));
555
556	/*
557	 * Special case for BIO_DELETE.  On the surface, this is very
558	 * similar to BIO_WRITE, except that we write from our own
559	 * fixed-length buffer, so we have to loop.  The net result is
560	 * that the two cases end up having very little in common.
561	 */
562	if (bp->bio_cmd == BIO_DELETE) {
563		zerosize = ZERO_REGION_SIZE -
564		    (ZERO_REGION_SIZE % sc->sectorsize);
565		auio.uio_iov = &aiov;
566		auio.uio_iovcnt = 1;
567		auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
568		auio.uio_segflg = UIO_SYSSPACE;
569		auio.uio_rw = UIO_WRITE;
570		auio.uio_td = td;
571		end = bp->bio_offset + bp->bio_length;
572		vfslocked = VFS_LOCK_GIANT(vp->v_mount);
573		(void) vn_start_write(vp, &mp, V_WAIT);
574		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
575		error = 0;
576		while (auio.uio_offset < end) {
577			aiov.iov_base = __DECONST(void *, zero_region);
578			aiov.iov_len = end - auio.uio_offset;
579			if (aiov.iov_len > zerosize)
580				aiov.iov_len = zerosize;
581			auio.uio_resid = aiov.iov_len;
582			error = VOP_WRITE(vp, &auio,
583			    sc->flags & MD_ASYNC ? 0 : IO_SYNC, sc->cred);
584			if (error != 0)
585				break;
586		}
587		VOP_UNLOCK(vp, 0);
588		vn_finished_write(mp);
589		bp->bio_resid = end - auio.uio_offset;
590		VFS_UNLOCK_GIANT(vfslocked);
591		return (error);
592	}
593
594	aiov.iov_base = bp->bio_data;
595	aiov.iov_len = bp->bio_length;
596	auio.uio_iov = &aiov;
597	auio.uio_iovcnt = 1;
598	auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
599	auio.uio_segflg = UIO_SYSSPACE;
600	if (bp->bio_cmd == BIO_READ)
601		auio.uio_rw = UIO_READ;
602	else if (bp->bio_cmd == BIO_WRITE)
603		auio.uio_rw = UIO_WRITE;
604	else
605		panic("wrong BIO_OP in mdstart_vnode");
606	auio.uio_resid = bp->bio_length;
607	auio.uio_td = td;
608	/*
609	 * When reading set IO_DIRECT to try to avoid double-caching
610	 * the data.  When writing IO_DIRECT is not optimal.
611	 */
612	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
613	if (bp->bio_cmd == BIO_READ) {
614		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
615		error = VOP_READ(vp, &auio, IO_DIRECT, sc->cred);
616		VOP_UNLOCK(vp, 0);
617	} else {
618		(void) vn_start_write(vp, &mp, V_WAIT);
619		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
620		error = VOP_WRITE(vp, &auio, sc->flags & MD_ASYNC ? 0 : IO_SYNC,
621		    sc->cred);
622		VOP_UNLOCK(vp, 0);
623		vn_finished_write(mp);
624	}
625	VFS_UNLOCK_GIANT(vfslocked);
626	bp->bio_resid = auio.uio_resid;
627	return (error);
628}
629
630static int
631mdstart_swap(struct md_s *sc, struct bio *bp)
632{
633	struct sf_buf *sf;
634	int rv, offs, len, lastend;
635	vm_pindex_t i, lastp;
636	vm_page_t m;
637	u_char *p;
638
639	switch (bp->bio_cmd) {
640	case BIO_READ:
641	case BIO_WRITE:
642	case BIO_DELETE:
643		break;
644	default:
645		return (EOPNOTSUPP);
646	}
647
648	p = bp->bio_data;
649
650	/*
651	 * offs is the offset at which to start operating on the
652	 * next (ie, first) page.  lastp is the last page on
653	 * which we're going to operate.  lastend is the ending
654	 * position within that last page (ie, PAGE_SIZE if
655	 * we're operating on complete aligned pages).
656	 */
657	offs = bp->bio_offset % PAGE_SIZE;
658	lastp = (bp->bio_offset + bp->bio_length - 1) / PAGE_SIZE;
659	lastend = (bp->bio_offset + bp->bio_length - 1) % PAGE_SIZE + 1;
660
661	rv = VM_PAGER_OK;
662	VM_OBJECT_LOCK(sc->object);
663	vm_object_pip_add(sc->object, 1);
664	for (i = bp->bio_offset / PAGE_SIZE; i <= lastp; i++) {
665		len = ((i == lastp) ? lastend : PAGE_SIZE) - offs;
666
667		m = vm_page_grab(sc->object, i,
668		    VM_ALLOC_NORMAL|VM_ALLOC_RETRY);
669		VM_OBJECT_UNLOCK(sc->object);
670		sched_pin();
671		sf = sf_buf_alloc(m, SFB_CPUPRIVATE);
672		VM_OBJECT_LOCK(sc->object);
673		if (bp->bio_cmd == BIO_READ) {
674			if (m->valid != VM_PAGE_BITS_ALL)
675				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
676			if (rv == VM_PAGER_ERROR) {
677				sf_buf_free(sf);
678				sched_unpin();
679				vm_page_wakeup(m);
680				break;
681			}
682			bcopy((void *)(sf_buf_kva(sf) + offs), p, len);
683			cpu_flush_dcache(p, len);
684		} else if (bp->bio_cmd == BIO_WRITE) {
685			if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
686				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
687			if (rv == VM_PAGER_ERROR) {
688				sf_buf_free(sf);
689				sched_unpin();
690				vm_page_wakeup(m);
691				break;
692			}
693			bcopy(p, (void *)(sf_buf_kva(sf) + offs), len);
694			m->valid = VM_PAGE_BITS_ALL;
695		} else if (bp->bio_cmd == BIO_DELETE) {
696			if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
697				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
698			if (rv == VM_PAGER_ERROR) {
699				sf_buf_free(sf);
700				sched_unpin();
701				vm_page_wakeup(m);
702				break;
703			}
704			if (len != PAGE_SIZE) {
705				bzero((void *)(sf_buf_kva(sf) + offs), len);
706				vm_page_clear_dirty(m, offs, len);
707				m->valid = VM_PAGE_BITS_ALL;
708			} else
709				vm_pager_page_unswapped(m);
710		}
711		sf_buf_free(sf);
712		sched_unpin();
713		vm_page_wakeup(m);
714		vm_page_lock(m);
715		if (bp->bio_cmd == BIO_DELETE && len == PAGE_SIZE)
716			vm_page_free(m);
717		else
718			vm_page_activate(m);
719		vm_page_unlock(m);
720		if (bp->bio_cmd == BIO_WRITE)
721			vm_page_dirty(m);
722
723		/* Actions on further pages start at offset 0 */
724		p += PAGE_SIZE - offs;
725		offs = 0;
726#if 0
727if (bootverbose || bp->bio_offset / PAGE_SIZE < 17)
728printf("wire_count %d busy %d flags %x hold_count %d act_count %d queue %d valid %d dirty %d @ %d\n",
729    m->wire_count, m->busy,
730    m->flags, m->hold_count, m->act_count, m->queue, m->valid, m->dirty, i);
731#endif
732	}
733	vm_object_pip_subtract(sc->object, 1);
734	VM_OBJECT_UNLOCK(sc->object);
735	return (rv != VM_PAGER_ERROR ? 0 : ENOSPC);
736}
737
738static void
739md_kthread(void *arg)
740{
741	struct md_s *sc;
742	struct bio *bp;
743	int error;
744
745	sc = arg;
746	thread_lock(curthread);
747	sched_prio(curthread, PRIBIO);
748	thread_unlock(curthread);
749	if (sc->type == MD_VNODE)
750		curthread->td_pflags |= TDP_NORUNNINGBUF;
751
752	for (;;) {
753		mtx_lock(&sc->queue_mtx);
754		if (sc->flags & MD_SHUTDOWN) {
755			sc->flags |= MD_EXITING;
756			mtx_unlock(&sc->queue_mtx);
757			kproc_exit(0);
758		}
759		bp = bioq_takefirst(&sc->bio_queue);
760		if (!bp) {
761			msleep(sc, &sc->queue_mtx, PRIBIO | PDROP, "mdwait", 0);
762			continue;
763		}
764		mtx_unlock(&sc->queue_mtx);
765		if (bp->bio_cmd == BIO_GETATTR) {
766			if ((sc->fwsectors && sc->fwheads &&
767			    (g_handleattr_int(bp, "GEOM::fwsectors",
768			    sc->fwsectors) ||
769			    g_handleattr_int(bp, "GEOM::fwheads",
770			    sc->fwheads))) ||
771			    g_handleattr_int(bp, "GEOM::candelete", 1))
772				error = -1;
773			else
774				error = EOPNOTSUPP;
775		} else {
776			error = sc->start(sc, bp);
777		}
778
779		if (error != -1) {
780			bp->bio_completed = bp->bio_length;
781			if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
782				devstat_end_transaction_bio(sc->devstat, bp);
783			g_io_deliver(bp, error);
784		}
785	}
786}
787
788static struct md_s *
789mdfind(int unit)
790{
791	struct md_s *sc;
792
793	LIST_FOREACH(sc, &md_softc_list, list) {
794		if (sc->unit == unit)
795			break;
796	}
797	return (sc);
798}
799
800static struct md_s *
801mdnew(int unit, int *errp, enum md_types type)
802{
803	struct md_s *sc;
804	int error;
805
806	*errp = 0;
807	if (unit == -1)
808		unit = alloc_unr(md_uh);
809	else
810		unit = alloc_unr_specific(md_uh, unit);
811
812	if (unit == -1) {
813		*errp = EBUSY;
814		return (NULL);
815	}
816
817	sc = (struct md_s *)malloc(sizeof *sc, M_MD, M_WAITOK | M_ZERO);
818	sc->type = type;
819	bioq_init(&sc->bio_queue);
820	mtx_init(&sc->queue_mtx, "md bio queue", NULL, MTX_DEF);
821	sc->unit = unit;
822	sprintf(sc->name, "md%d", unit);
823	LIST_INSERT_HEAD(&md_softc_list, sc, list);
824	error = kproc_create(md_kthread, sc, &sc->procp, 0, 0,"%s", sc->name);
825	if (error == 0)
826		return (sc);
827	LIST_REMOVE(sc, list);
828	mtx_destroy(&sc->queue_mtx);
829	free_unr(md_uh, sc->unit);
830	free(sc, M_MD);
831	*errp = error;
832	return (NULL);
833}
834
835static void
836mdinit(struct md_s *sc)
837{
838	struct g_geom *gp;
839	struct g_provider *pp;
840
841	g_topology_lock();
842	gp = g_new_geomf(&g_md_class, "md%d", sc->unit);
843	gp->softc = sc;
844	pp = g_new_providerf(gp, "md%d", sc->unit);
845	pp->mediasize = sc->mediasize;
846	pp->sectorsize = sc->sectorsize;
847	sc->gp = gp;
848	sc->pp = pp;
849	g_error_provider(pp, 0);
850	g_topology_unlock();
851	sc->devstat = devstat_new_entry("md", sc->unit, sc->sectorsize,
852	    DEVSTAT_ALL_SUPPORTED, DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
853}
854
855/*
856 * XXX: we should check that the range they feed us is mapped.
857 * XXX: we should implement read-only.
858 */
859
860static int
861mdcreate_preload(struct md_s *sc, struct md_ioctl *mdio)
862{
863
864	if (mdio->md_options & ~(MD_AUTOUNIT | MD_FORCE))
865		return (EINVAL);
866	if (mdio->md_base == 0)
867		return (EINVAL);
868	sc->flags = mdio->md_options & MD_FORCE;
869	/* Cast to pointer size, then to pointer to avoid warning */
870	sc->pl_ptr = (u_char *)(uintptr_t)mdio->md_base;
871	sc->pl_len = (size_t)sc->mediasize;
872	return (0);
873}
874
875
876static int
877mdcreate_malloc(struct md_s *sc, struct md_ioctl *mdio)
878{
879	uintptr_t sp;
880	int error;
881	off_t u;
882
883	error = 0;
884	if (mdio->md_options & ~(MD_AUTOUNIT | MD_COMPRESS | MD_RESERVE))
885		return (EINVAL);
886	if (mdio->md_sectorsize != 0 && !powerof2(mdio->md_sectorsize))
887		return (EINVAL);
888	/* Compression doesn't make sense if we have reserved space */
889	if (mdio->md_options & MD_RESERVE)
890		mdio->md_options &= ~MD_COMPRESS;
891	if (mdio->md_fwsectors != 0)
892		sc->fwsectors = mdio->md_fwsectors;
893	if (mdio->md_fwheads != 0)
894		sc->fwheads = mdio->md_fwheads;
895	sc->flags = mdio->md_options & (MD_COMPRESS | MD_FORCE);
896	sc->indir = dimension(sc->mediasize / sc->sectorsize);
897	sc->uma = uma_zcreate(sc->name, sc->sectorsize, NULL, NULL, NULL, NULL,
898	    0x1ff, 0);
899	if (mdio->md_options & MD_RESERVE) {
900		off_t nsectors;
901
902		nsectors = sc->mediasize / sc->sectorsize;
903		for (u = 0; u < nsectors; u++) {
904			sp = (uintptr_t)uma_zalloc(sc->uma, (md_malloc_wait ?
905			    M_WAITOK : M_NOWAIT) | M_ZERO);
906			if (sp != 0)
907				error = s_write(sc->indir, u, sp);
908			else
909				error = ENOMEM;
910			if (error != 0)
911				break;
912		}
913	}
914	return (error);
915}
916
917
918static int
919mdsetcred(struct md_s *sc, struct ucred *cred)
920{
921	char *tmpbuf;
922	int error = 0;
923
924	/*
925	 * Set credits in our softc
926	 */
927
928	if (sc->cred)
929		crfree(sc->cred);
930	sc->cred = crhold(cred);
931
932	/*
933	 * Horrible kludge to establish credentials for NFS  XXX.
934	 */
935
936	if (sc->vnode) {
937		struct uio auio;
938		struct iovec aiov;
939
940		tmpbuf = malloc(sc->sectorsize, M_TEMP, M_WAITOK);
941		bzero(&auio, sizeof(auio));
942
943		aiov.iov_base = tmpbuf;
944		aiov.iov_len = sc->sectorsize;
945		auio.uio_iov = &aiov;
946		auio.uio_iovcnt = 1;
947		auio.uio_offset = 0;
948		auio.uio_rw = UIO_READ;
949		auio.uio_segflg = UIO_SYSSPACE;
950		auio.uio_resid = aiov.iov_len;
951		vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY);
952		error = VOP_READ(sc->vnode, &auio, 0, sc->cred);
953		VOP_UNLOCK(sc->vnode, 0);
954		free(tmpbuf, M_TEMP);
955	}
956	return (error);
957}
958
959static int
960mdcreate_vnode(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
961{
962	struct vattr vattr;
963	struct nameidata nd;
964	char *fname;
965	int error, flags, vfslocked;
966
967	/*
968	 * Kernel-originated requests must have the filename appended
969	 * to the mdio structure to protect against malicious software.
970	 */
971	fname = mdio->md_file;
972	if ((void *)fname != (void *)(mdio + 1)) {
973		error = copyinstr(fname, sc->file, sizeof(sc->file), NULL);
974		if (error != 0)
975			return (error);
976	} else
977		strlcpy(sc->file, fname, sizeof(sc->file));
978
979	/*
980	 * If the user specified that this is a read only device, don't
981	 * set the FWRITE mask before trying to open the backing store.
982	 */
983	flags = FREAD | ((mdio->md_options & MD_READONLY) ? 0 : FWRITE);
984	NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, sc->file, td);
985	error = vn_open(&nd, &flags, 0, NULL);
986	if (error != 0)
987		return (error);
988	vfslocked = NDHASGIANT(&nd);
989	NDFREE(&nd, NDF_ONLY_PNBUF);
990	if (nd.ni_vp->v_type != VREG) {
991		error = EINVAL;
992		goto bad;
993	}
994	error = VOP_GETATTR(nd.ni_vp, &vattr, td->td_ucred);
995	if (error != 0)
996		goto bad;
997	if (VOP_ISLOCKED(nd.ni_vp) != LK_EXCLUSIVE) {
998		vn_lock(nd.ni_vp, LK_UPGRADE | LK_RETRY);
999		if (nd.ni_vp->v_iflag & VI_DOOMED) {
1000			/* Forced unmount. */
1001			error = EBADF;
1002			goto bad;
1003		}
1004	}
1005	nd.ni_vp->v_vflag |= VV_MD;
1006	VOP_UNLOCK(nd.ni_vp, 0);
1007
1008	if (mdio->md_fwsectors != 0)
1009		sc->fwsectors = mdio->md_fwsectors;
1010	if (mdio->md_fwheads != 0)
1011		sc->fwheads = mdio->md_fwheads;
1012	sc->flags = mdio->md_options & (MD_FORCE | MD_ASYNC);
1013	if (!(flags & FWRITE))
1014		sc->flags |= MD_READONLY;
1015	sc->vnode = nd.ni_vp;
1016
1017	error = mdsetcred(sc, td->td_ucred);
1018	if (error != 0) {
1019		sc->vnode = NULL;
1020		vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
1021		nd.ni_vp->v_vflag &= ~VV_MD;
1022		goto bad;
1023	}
1024	VFS_UNLOCK_GIANT(vfslocked);
1025	return (0);
1026bad:
1027	VOP_UNLOCK(nd.ni_vp, 0);
1028	(void)vn_close(nd.ni_vp, flags, td->td_ucred, td);
1029	VFS_UNLOCK_GIANT(vfslocked);
1030	return (error);
1031}
1032
1033static int
1034mddestroy(struct md_s *sc, struct thread *td)
1035{
1036	int vfslocked;
1037
1038	if (sc->gp) {
1039		sc->gp->softc = NULL;
1040		g_topology_lock();
1041		g_wither_geom(sc->gp, ENXIO);
1042		g_topology_unlock();
1043		sc->gp = NULL;
1044		sc->pp = NULL;
1045	}
1046	if (sc->devstat) {
1047		devstat_remove_entry(sc->devstat);
1048		sc->devstat = NULL;
1049	}
1050	mtx_lock(&sc->queue_mtx);
1051	sc->flags |= MD_SHUTDOWN;
1052	wakeup(sc);
1053	while (!(sc->flags & MD_EXITING))
1054		msleep(sc->procp, &sc->queue_mtx, PRIBIO, "mddestroy", hz / 10);
1055	mtx_unlock(&sc->queue_mtx);
1056	mtx_destroy(&sc->queue_mtx);
1057	if (sc->vnode != NULL) {
1058		vfslocked = VFS_LOCK_GIANT(sc->vnode->v_mount);
1059		vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY);
1060		sc->vnode->v_vflag &= ~VV_MD;
1061		VOP_UNLOCK(sc->vnode, 0);
1062		(void)vn_close(sc->vnode, sc->flags & MD_READONLY ?
1063		    FREAD : (FREAD|FWRITE), sc->cred, td);
1064		VFS_UNLOCK_GIANT(vfslocked);
1065	}
1066	if (sc->cred != NULL)
1067		crfree(sc->cred);
1068	if (sc->object != NULL)
1069		vm_object_deallocate(sc->object);
1070	if (sc->indir)
1071		destroy_indir(sc, sc->indir);
1072	if (sc->uma)
1073		uma_zdestroy(sc->uma);
1074
1075	LIST_REMOVE(sc, list);
1076	free_unr(md_uh, sc->unit);
1077	free(sc, M_MD);
1078	return (0);
1079}
1080
1081static int
1082mdcreate_swap(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
1083{
1084	vm_ooffset_t npage;
1085	int error;
1086
1087	/*
1088	 * Range check.  Disallow negative sizes or any size less then the
1089	 * size of a page.  Then round to a page.
1090	 */
1091	if (sc->mediasize == 0 || (sc->mediasize % PAGE_SIZE) != 0)
1092		return (EDOM);
1093
1094	/*
1095	 * Allocate an OBJT_SWAP object.
1096	 *
1097	 * Note the truncation.
1098	 */
1099
1100	npage = mdio->md_mediasize / PAGE_SIZE;
1101	if (mdio->md_fwsectors != 0)
1102		sc->fwsectors = mdio->md_fwsectors;
1103	if (mdio->md_fwheads != 0)
1104		sc->fwheads = mdio->md_fwheads;
1105	sc->object = vm_pager_allocate(OBJT_SWAP, NULL, PAGE_SIZE * npage,
1106	    VM_PROT_DEFAULT, 0, td->td_ucred);
1107	if (sc->object == NULL)
1108		return (ENOMEM);
1109	sc->flags = mdio->md_options & MD_FORCE;
1110	if (mdio->md_options & MD_RESERVE) {
1111		if (swap_pager_reserve(sc->object, 0, npage) < 0) {
1112			error = EDOM;
1113			goto finish;
1114		}
1115	}
1116	error = mdsetcred(sc, td->td_ucred);
1117 finish:
1118	if (error != 0) {
1119		vm_object_deallocate(sc->object);
1120		sc->object = NULL;
1121	}
1122	return (error);
1123}
1124
1125
1126static int
1127xmdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
1128{
1129	struct md_ioctl *mdio;
1130	struct md_s *sc;
1131	int error, i;
1132
1133	if (md_debug)
1134		printf("mdctlioctl(%s %lx %p %x %p)\n",
1135			devtoname(dev), cmd, addr, flags, td);
1136
1137	mdio = (struct md_ioctl *)addr;
1138	if (mdio->md_version != MDIOVERSION)
1139		return (EINVAL);
1140
1141	/*
1142	 * We assert the version number in the individual ioctl
1143	 * handlers instead of out here because (a) it is possible we
1144	 * may add another ioctl in the future which doesn't read an
1145	 * mdio, and (b) the correct return value for an unknown ioctl
1146	 * is ENOIOCTL, not EINVAL.
1147	 */
1148	error = 0;
1149	switch (cmd) {
1150	case MDIOCATTACH:
1151		switch (mdio->md_type) {
1152		case MD_MALLOC:
1153		case MD_PRELOAD:
1154		case MD_VNODE:
1155		case MD_SWAP:
1156			break;
1157		default:
1158			return (EINVAL);
1159		}
1160		if (mdio->md_options & MD_AUTOUNIT)
1161			sc = mdnew(-1, &error, mdio->md_type);
1162		else {
1163			if (mdio->md_unit > INT_MAX)
1164				return (EINVAL);
1165			sc = mdnew(mdio->md_unit, &error, mdio->md_type);
1166		}
1167		if (sc == NULL)
1168			return (error);
1169		if (mdio->md_options & MD_AUTOUNIT)
1170			mdio->md_unit = sc->unit;
1171		sc->mediasize = mdio->md_mediasize;
1172		if (mdio->md_sectorsize == 0)
1173			sc->sectorsize = DEV_BSIZE;
1174		else
1175			sc->sectorsize = mdio->md_sectorsize;
1176		error = EDOOFUS;
1177		switch (sc->type) {
1178		case MD_MALLOC:
1179			sc->start = mdstart_malloc;
1180			error = mdcreate_malloc(sc, mdio);
1181			break;
1182		case MD_PRELOAD:
1183			sc->start = mdstart_preload;
1184			error = mdcreate_preload(sc, mdio);
1185			break;
1186		case MD_VNODE:
1187			sc->start = mdstart_vnode;
1188			error = mdcreate_vnode(sc, mdio, td);
1189			break;
1190		case MD_SWAP:
1191			sc->start = mdstart_swap;
1192			error = mdcreate_swap(sc, mdio, td);
1193			break;
1194		}
1195		if (error != 0) {
1196			mddestroy(sc, td);
1197			return (error);
1198		}
1199
1200		/* Prune off any residual fractional sector */
1201		i = sc->mediasize % sc->sectorsize;
1202		sc->mediasize -= i;
1203
1204		mdinit(sc);
1205		return (0);
1206	case MDIOCDETACH:
1207		if (mdio->md_mediasize != 0 ||
1208		    (mdio->md_options & ~MD_FORCE) != 0)
1209			return (EINVAL);
1210
1211		sc = mdfind(mdio->md_unit);
1212		if (sc == NULL)
1213			return (ENOENT);
1214		if (sc->opencount != 0 && !(sc->flags & MD_FORCE) &&
1215		    !(mdio->md_options & MD_FORCE))
1216			return (EBUSY);
1217		return (mddestroy(sc, td));
1218	case MDIOCQUERY:
1219		sc = mdfind(mdio->md_unit);
1220		if (sc == NULL)
1221			return (ENOENT);
1222		mdio->md_type = sc->type;
1223		mdio->md_options = sc->flags;
1224		mdio->md_mediasize = sc->mediasize;
1225		mdio->md_sectorsize = sc->sectorsize;
1226		if (sc->type == MD_VNODE)
1227			error = copyout(sc->file, mdio->md_file,
1228			    strlen(sc->file) + 1);
1229		return (error);
1230	case MDIOCLIST:
1231		i = 1;
1232		LIST_FOREACH(sc, &md_softc_list, list) {
1233			if (i == MDNPAD - 1)
1234				mdio->md_pad[i] = -1;
1235			else
1236				mdio->md_pad[i++] = sc->unit;
1237		}
1238		mdio->md_pad[0] = i - 1;
1239		return (0);
1240	default:
1241		return (ENOIOCTL);
1242	};
1243}
1244
1245static int
1246mdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
1247{
1248	int error;
1249
1250	sx_xlock(&md_sx);
1251	error = xmdctlioctl(dev, cmd, addr, flags, td);
1252	sx_xunlock(&md_sx);
1253	return (error);
1254}
1255
1256static void
1257md_preloaded(u_char *image, size_t length)
1258{
1259	struct md_s *sc;
1260	int error;
1261
1262	sc = mdnew(-1, &error, MD_PRELOAD);
1263	if (sc == NULL)
1264		return;
1265	sc->mediasize = length;
1266	sc->sectorsize = DEV_BSIZE;
1267	sc->pl_ptr = image;
1268	sc->pl_len = length;
1269	sc->start = mdstart_preload;
1270#ifdef MD_ROOT
1271	if (sc->unit == 0)
1272		rootdevnames[0] = "ufs:/dev/md0";
1273#endif
1274	mdinit(sc);
1275}
1276
1277static void
1278g_md_init(struct g_class *mp __unused)
1279{
1280	caddr_t mod;
1281	u_char *ptr, *name, *type;
1282	unsigned len;
1283	int i;
1284
1285	/* figure out log2(NINDIR) */
1286	for (i = NINDIR, nshift = -1; i; nshift++)
1287		i >>= 1;
1288
1289	mod = NULL;
1290	sx_init(&md_sx, "MD config lock");
1291	g_topology_unlock();
1292	md_uh = new_unrhdr(0, INT_MAX, NULL);
1293#ifdef MD_ROOT_SIZE
1294	sx_xlock(&md_sx);
1295	md_preloaded(mfs_root.start, sizeof(mfs_root.start));
1296	sx_xunlock(&md_sx);
1297#endif
1298	/* XXX: are preload_* static or do they need Giant ? */
1299	while ((mod = preload_search_next_name(mod)) != NULL) {
1300		name = (char *)preload_search_info(mod, MODINFO_NAME);
1301		if (name == NULL)
1302			continue;
1303		type = (char *)preload_search_info(mod, MODINFO_TYPE);
1304		if (type == NULL)
1305			continue;
1306		if (strcmp(type, "md_image") && strcmp(type, "mfs_root"))
1307			continue;
1308		ptr = preload_fetch_addr(mod);
1309		len = preload_fetch_size(mod);
1310		if (ptr != NULL && len != 0) {
1311			printf("%s%d: Preloaded image <%s> %d bytes at %p\n",
1312			    MD_NAME, mdunits, name, len, ptr);
1313			sx_xlock(&md_sx);
1314			md_preloaded(ptr, len);
1315			sx_xunlock(&md_sx);
1316		}
1317	}
1318	status_dev = make_dev(&mdctl_cdevsw, INT_MAX, UID_ROOT, GID_WHEEL,
1319	    0600, MDCTL_NAME);
1320	g_topology_lock();
1321}
1322
1323static void
1324g_md_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1325    struct g_consumer *cp __unused, struct g_provider *pp)
1326{
1327	struct md_s *mp;
1328	char *type;
1329
1330	mp = gp->softc;
1331	if (mp == NULL)
1332		return;
1333
1334	switch (mp->type) {
1335	case MD_MALLOC:
1336		type = "malloc";
1337		break;
1338	case MD_PRELOAD:
1339		type = "preload";
1340		break;
1341	case MD_VNODE:
1342		type = "vnode";
1343		break;
1344	case MD_SWAP:
1345		type = "swap";
1346		break;
1347	default:
1348		type = "unknown";
1349		break;
1350	}
1351
1352	if (pp != NULL) {
1353		if (indent == NULL) {
1354			sbuf_printf(sb, " u %d", mp->unit);
1355			sbuf_printf(sb, " s %ju", (uintmax_t) mp->sectorsize);
1356			sbuf_printf(sb, " f %ju", (uintmax_t) mp->fwheads);
1357			sbuf_printf(sb, " fs %ju", (uintmax_t) mp->fwsectors);
1358			sbuf_printf(sb, " l %ju", (uintmax_t) mp->mediasize);
1359			sbuf_printf(sb, " t %s", type);
1360			if (mp->type == MD_VNODE && mp->vnode != NULL)
1361				sbuf_printf(sb, " file %s", mp->file);
1362		} else {
1363			sbuf_printf(sb, "%s<unit>%d</unit>\n", indent,
1364			    mp->unit);
1365			sbuf_printf(sb, "%s<sectorsize>%ju</sectorsize>\n",
1366			    indent, (uintmax_t) mp->sectorsize);
1367			sbuf_printf(sb, "%s<fwheads>%ju</fwheads>\n",
1368			    indent, (uintmax_t) mp->fwheads);
1369			sbuf_printf(sb, "%s<fwsectors>%ju</fwsectors>\n",
1370			    indent, (uintmax_t) mp->fwsectors);
1371			sbuf_printf(sb, "%s<length>%ju</length>\n",
1372			    indent, (uintmax_t) mp->mediasize);
1373			sbuf_printf(sb, "%s<type>%s</type>\n", indent,
1374			    type);
1375			if (mp->type == MD_VNODE && mp->vnode != NULL)
1376				sbuf_printf(sb, "%s<file>%s</file>\n",
1377				    indent, mp->file);
1378		}
1379	}
1380}
1381
1382static void
1383g_md_fini(struct g_class *mp __unused)
1384{
1385
1386	sx_destroy(&md_sx);
1387	if (status_dev != NULL)
1388		destroy_dev(status_dev);
1389	delete_unrhdr(md_uh);
1390}
1391