freebsd-skq/sys/dev/md/md.c
Konstantin Belousov 537cc627d7 Fix the data corruption on the swap-backed md.
Assign the rv variable a success code if the pager was not asked for
the page.  Using an error code from the previous processed page caused
zeroing of the valid page, when e.g. the previous page was not
available in the pager.

Reported by:	lstewart
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2013-05-24 09:48:42 +00:00

1631 lines
38 KiB
C

/*-
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
* $FreeBSD$
*
*/
/*-
* The following functions are based in the vn(4) driver: mdstart_swap(),
* mdstart_vnode(), mdcreate_swap(), mdcreate_vnode() and mddestroy(),
* and as such under the following copyright:
*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
* Copyright (c) 2013 The FreeBSD Foundation
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Portions of this software were developed by Konstantin Belousov
* under sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: Utah Hdr: vn.c 1.13 94/04/02
*
* from: @(#)vn.c 8.6 (Berkeley) 4/1/94
* From: src/sys/dev/vn/vn.c,v 1.122 2000/12/16 16:06:03
*/
#include "opt_geom.h"
#include "opt_md.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/devicestat.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/limits.h>
#include <sys/linker.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mdioctl.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/sx.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/rwlock.h>
#include <sys/sbuf.h>
#include <sys/sched.h>
#include <sys/sf_buf.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <geom/geom.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/swap_pager.h>
#include <vm/uma.h>
#define MD_MODVER 1
#define MD_SHUTDOWN 0x10000 /* Tell worker thread to terminate. */
#define MD_EXITING 0x20000 /* Worker thread is exiting. */
#ifndef MD_NSECT
#define MD_NSECT (10000 * 2)
#endif
static MALLOC_DEFINE(M_MD, "md_disk", "Memory Disk");
static MALLOC_DEFINE(M_MDSECT, "md_sectors", "Memory Disk Sectors");
static int md_debug;
SYSCTL_INT(_debug, OID_AUTO, mddebug, CTLFLAG_RW, &md_debug, 0,
"Enable md(4) debug messages");
static int md_malloc_wait;
SYSCTL_INT(_vm, OID_AUTO, md_malloc_wait, CTLFLAG_RW, &md_malloc_wait, 0,
"Allow malloc to wait for memory allocations");
#if defined(MD_ROOT) && !defined(MD_ROOT_FSTYPE)
#define MD_ROOT_FSTYPE "ufs"
#endif
#if defined(MD_ROOT) && defined(MD_ROOT_SIZE)
/*
* Preloaded image gets put here.
* Applications that patch the object with the image can determine
* the size looking at the start and end markers (strings),
* so we want them contiguous.
*/
static struct {
u_char start[MD_ROOT_SIZE*1024];
u_char end[128];
} mfs_root = {
.start = "MFS Filesystem goes here",
.end = "MFS Filesystem had better STOP here",
};
#endif
static g_init_t g_md_init;
static g_fini_t g_md_fini;
static g_start_t g_md_start;
static g_access_t g_md_access;
static void g_md_dumpconf(struct sbuf *sb, const char *indent,
struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp);
static struct cdev *status_dev = 0;
static struct sx md_sx;
static struct unrhdr *md_uh;
static d_ioctl_t mdctlioctl;
static struct cdevsw mdctl_cdevsw = {
.d_version = D_VERSION,
.d_ioctl = mdctlioctl,
.d_name = MD_NAME,
};
struct g_class g_md_class = {
.name = "MD",
.version = G_VERSION,
.init = g_md_init,
.fini = g_md_fini,
.start = g_md_start,
.access = g_md_access,
.dumpconf = g_md_dumpconf,
};
DECLARE_GEOM_CLASS(g_md_class, g_md);
static LIST_HEAD(, md_s) md_softc_list = LIST_HEAD_INITIALIZER(md_softc_list);
#define NINDIR (PAGE_SIZE / sizeof(uintptr_t))
#define NMASK (NINDIR-1)
static int nshift;
static int md_vnode_pbuf_freecnt;
struct indir {
uintptr_t *array;
u_int total;
u_int used;
u_int shift;
};
struct md_s {
int unit;
LIST_ENTRY(md_s) list;
struct bio_queue_head bio_queue;
struct mtx queue_mtx;
struct cdev *dev;
enum md_types type;
off_t mediasize;
unsigned sectorsize;
unsigned opencount;
unsigned fwheads;
unsigned fwsectors;
unsigned flags;
char name[20];
struct proc *procp;
struct g_geom *gp;
struct g_provider *pp;
int (*start)(struct md_s *sc, struct bio *bp);
struct devstat *devstat;
/* MD_MALLOC related fields */
struct indir *indir;
uma_zone_t uma;
/* MD_PRELOAD related fields */
u_char *pl_ptr;
size_t pl_len;
/* MD_VNODE related fields */
struct vnode *vnode;
char file[PATH_MAX];
struct ucred *cred;
/* MD_SWAP related fields */
vm_object_t object;
};
static struct indir *
new_indir(u_int shift)
{
struct indir *ip;
ip = malloc(sizeof *ip, M_MD, (md_malloc_wait ? M_WAITOK : M_NOWAIT)
| M_ZERO);
if (ip == NULL)
return (NULL);
ip->array = malloc(sizeof(uintptr_t) * NINDIR,
M_MDSECT, (md_malloc_wait ? M_WAITOK : M_NOWAIT) | M_ZERO);
if (ip->array == NULL) {
free(ip, M_MD);
return (NULL);
}
ip->total = NINDIR;
ip->shift = shift;
return (ip);
}
static void
del_indir(struct indir *ip)
{
free(ip->array, M_MDSECT);
free(ip, M_MD);
}
static void
destroy_indir(struct md_s *sc, struct indir *ip)
{
int i;
for (i = 0; i < NINDIR; i++) {
if (!ip->array[i])
continue;
if (ip->shift)
destroy_indir(sc, (struct indir*)(ip->array[i]));
else if (ip->array[i] > 255)
uma_zfree(sc->uma, (void *)(ip->array[i]));
}
del_indir(ip);
}
/*
* This function does the math and allocates the top level "indir" structure
* for a device of "size" sectors.
*/
static struct indir *
dimension(off_t size)
{
off_t rcnt;
struct indir *ip;
int layer;
rcnt = size;
layer = 0;
while (rcnt > NINDIR) {
rcnt /= NINDIR;
layer++;
}
/*
* XXX: the top layer is probably not fully populated, so we allocate
* too much space for ip->array in here.
*/
ip = malloc(sizeof *ip, M_MD, M_WAITOK | M_ZERO);
ip->array = malloc(sizeof(uintptr_t) * NINDIR,
M_MDSECT, M_WAITOK | M_ZERO);
ip->total = NINDIR;
ip->shift = layer * nshift;
return (ip);
}
/*
* Read a given sector
*/
static uintptr_t
s_read(struct indir *ip, off_t offset)
{
struct indir *cip;
int idx;
uintptr_t up;
if (md_debug > 1)
printf("s_read(%jd)\n", (intmax_t)offset);
up = 0;
for (cip = ip; cip != NULL;) {
if (cip->shift) {
idx = (offset >> cip->shift) & NMASK;
up = cip->array[idx];
cip = (struct indir *)up;
continue;
}
idx = offset & NMASK;
return (cip->array[idx]);
}
return (0);
}
/*
* Write a given sector, prune the tree if the value is 0
*/
static int
s_write(struct indir *ip, off_t offset, uintptr_t ptr)
{
struct indir *cip, *lip[10];
int idx, li;
uintptr_t up;
if (md_debug > 1)
printf("s_write(%jd, %p)\n", (intmax_t)offset, (void *)ptr);
up = 0;
li = 0;
cip = ip;
for (;;) {
lip[li++] = cip;
if (cip->shift) {
idx = (offset >> cip->shift) & NMASK;
up = cip->array[idx];
if (up != 0) {
cip = (struct indir *)up;
continue;
}
/* Allocate branch */
cip->array[idx] =
(uintptr_t)new_indir(cip->shift - nshift);
if (cip->array[idx] == 0)
return (ENOSPC);
cip->used++;
up = cip->array[idx];
cip = (struct indir *)up;
continue;
}
/* leafnode */
idx = offset & NMASK;
up = cip->array[idx];
if (up != 0)
cip->used--;
cip->array[idx] = ptr;
if (ptr != 0)
cip->used++;
break;
}
if (cip->used != 0 || li == 1)
return (0);
li--;
while (cip->used == 0 && cip != ip) {
li--;
idx = (offset >> lip[li]->shift) & NMASK;
up = lip[li]->array[idx];
KASSERT(up == (uintptr_t)cip, ("md screwed up"));
del_indir(cip);
lip[li]->array[idx] = 0;
lip[li]->used--;
cip = lip[li];
}
return (0);
}
static int
g_md_access(struct g_provider *pp, int r, int w, int e)
{
struct md_s *sc;
sc = pp->geom->softc;
if (sc == NULL) {
if (r <= 0 && w <= 0 && e <= 0)
return (0);
return (ENXIO);
}
r += pp->acr;
w += pp->acw;
e += pp->ace;
if ((sc->flags & MD_READONLY) != 0 && w > 0)
return (EROFS);
if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
sc->opencount = 1;
} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
sc->opencount = 0;
}
return (0);
}
static void
g_md_start(struct bio *bp)
{
struct md_s *sc;
sc = bp->bio_to->geom->softc;
if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
devstat_start_transaction_bio(sc->devstat, bp);
mtx_lock(&sc->queue_mtx);
bioq_disksort(&sc->bio_queue, bp);
mtx_unlock(&sc->queue_mtx);
wakeup(sc);
}
#define MD_MALLOC_MOVE_ZERO 1
#define MD_MALLOC_MOVE_FILL 2
#define MD_MALLOC_MOVE_READ 3
#define MD_MALLOC_MOVE_WRITE 4
#define MD_MALLOC_MOVE_CMP 5
static int
md_malloc_move(vm_page_t **mp, int *ma_offs, unsigned sectorsize,
void *ptr, u_char fill, int op)
{
struct sf_buf *sf;
vm_page_t m, *mp1;
char *p, first;
off_t *uc;
unsigned n;
int error, i, ma_offs1, sz, first_read;
m = NULL;
error = 0;
sf = NULL;
/* if (op == MD_MALLOC_MOVE_CMP) { gcc */
first = 0;
first_read = 0;
uc = ptr;
mp1 = *mp;
ma_offs1 = *ma_offs;
/* } */
sched_pin();
for (n = sectorsize; n != 0; n -= sz) {
sz = imin(PAGE_SIZE - *ma_offs, n);
if (m != **mp) {
if (sf != NULL)
sf_buf_free(sf);
m = **mp;
sf = sf_buf_alloc(m, SFB_CPUPRIVATE |
(md_malloc_wait ? 0 : SFB_NOWAIT));
if (sf == NULL) {
error = ENOMEM;
break;
}
}
p = (char *)sf_buf_kva(sf) + *ma_offs;
switch (op) {
case MD_MALLOC_MOVE_ZERO:
bzero(p, sz);
break;
case MD_MALLOC_MOVE_FILL:
memset(p, fill, sz);
break;
case MD_MALLOC_MOVE_READ:
bcopy(ptr, p, sz);
cpu_flush_dcache(p, sz);
break;
case MD_MALLOC_MOVE_WRITE:
bcopy(p, ptr, sz);
break;
case MD_MALLOC_MOVE_CMP:
for (i = 0; i < sz; i++, p++) {
if (!first_read) {
*uc = (u_char)*p;
first = *p;
first_read = 1;
} else if (*p != first) {
error = EDOOFUS;
break;
}
}
break;
default:
KASSERT(0, ("md_malloc_move unknown op %d\n", op));
break;
}
if (error != 0)
break;
*ma_offs += sz;
*ma_offs %= PAGE_SIZE;
if (*ma_offs == 0)
(*mp)++;
ptr = (char *)ptr + sz;
}
if (sf != NULL)
sf_buf_free(sf);
sched_unpin();
if (op == MD_MALLOC_MOVE_CMP && error != 0) {
*mp = mp1;
*ma_offs = ma_offs1;
}
return (error);
}
static int
mdstart_malloc(struct md_s *sc, struct bio *bp)
{
u_char *dst;
vm_page_t *m;
int i, error, error1, ma_offs, notmapped;
off_t secno, nsec, uc;
uintptr_t sp, osp;
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
break;
default:
return (EOPNOTSUPP);
}
notmapped = (bp->bio_flags & BIO_UNMAPPED) != 0;
if (notmapped) {
m = bp->bio_ma;
ma_offs = bp->bio_ma_offset;
dst = NULL;
} else {
dst = bp->bio_data;
}
nsec = bp->bio_length / sc->sectorsize;
secno = bp->bio_offset / sc->sectorsize;
error = 0;
while (nsec--) {
osp = s_read(sc->indir, secno);
if (bp->bio_cmd == BIO_DELETE) {
if (osp != 0)
error = s_write(sc->indir, secno, 0);
} else if (bp->bio_cmd == BIO_READ) {
if (osp == 0) {
if (notmapped) {
error = md_malloc_move(&m, &ma_offs,
sc->sectorsize, NULL, 0,
MD_MALLOC_MOVE_ZERO);
} else
bzero(dst, sc->sectorsize);
} else if (osp <= 255) {
if (notmapped) {
error = md_malloc_move(&m, &ma_offs,
sc->sectorsize, NULL, osp,
MD_MALLOC_MOVE_FILL);
} else
memset(dst, osp, sc->sectorsize);
} else {
if (notmapped) {
error = md_malloc_move(&m, &ma_offs,
sc->sectorsize, (void *)osp, 0,
MD_MALLOC_MOVE_READ);
} else {
bcopy((void *)osp, dst, sc->sectorsize);
cpu_flush_dcache(dst, sc->sectorsize);
}
}
osp = 0;
} else if (bp->bio_cmd == BIO_WRITE) {
if (sc->flags & MD_COMPRESS) {
if (notmapped) {
error1 = md_malloc_move(&m, &ma_offs,
sc->sectorsize, &uc, 0,
MD_MALLOC_MOVE_CMP);
i = error1 == 0 ? sc->sectorsize : 0;
} else {
uc = dst[0];
for (i = 1; i < sc->sectorsize; i++) {
if (dst[i] != uc)
break;
}
}
} else {
i = 0;
uc = 0;
}
if (i == sc->sectorsize) {
if (osp != uc)
error = s_write(sc->indir, secno, uc);
} else {
if (osp <= 255) {
sp = (uintptr_t)uma_zalloc(sc->uma,
md_malloc_wait ? M_WAITOK :
M_NOWAIT);
if (sp == 0) {
error = ENOSPC;
break;
}
if (notmapped) {
error = md_malloc_move(&m,
&ma_offs, sc->sectorsize,
(void *)sp, 0,
MD_MALLOC_MOVE_WRITE);
} else {
bcopy(dst, (void *)sp,
sc->sectorsize);
}
error = s_write(sc->indir, secno, sp);
} else {
if (notmapped) {
error = md_malloc_move(&m,
&ma_offs, sc->sectorsize,
(void *)osp, 0,
MD_MALLOC_MOVE_WRITE);
} else {
bcopy(dst, (void *)osp,
sc->sectorsize);
}
osp = 0;
}
}
} else {
error = EOPNOTSUPP;
}
if (osp > 255)
uma_zfree(sc->uma, (void*)osp);
if (error != 0)
break;
secno++;
if (!notmapped)
dst += sc->sectorsize;
}
bp->bio_resid = 0;
return (error);
}
static int
mdstart_preload(struct md_s *sc, struct bio *bp)
{
switch (bp->bio_cmd) {
case BIO_READ:
bcopy(sc->pl_ptr + bp->bio_offset, bp->bio_data,
bp->bio_length);
cpu_flush_dcache(bp->bio_data, bp->bio_length);
break;
case BIO_WRITE:
bcopy(bp->bio_data, sc->pl_ptr + bp->bio_offset,
bp->bio_length);
break;
}
bp->bio_resid = 0;
return (0);
}
static int
mdstart_vnode(struct md_s *sc, struct bio *bp)
{
int error;
struct uio auio;
struct iovec aiov;
struct mount *mp;
struct vnode *vp;
struct buf *pb;
struct thread *td;
off_t end, zerosize;
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
case BIO_FLUSH:
break;
default:
return (EOPNOTSUPP);
}
td = curthread;
vp = sc->vnode;
/*
* VNODE I/O
*
* If an error occurs, we set BIO_ERROR but we do not set
* B_INVAL because (for a write anyway), the buffer is
* still valid.
*/
if (bp->bio_cmd == BIO_FLUSH) {
(void) vn_start_write(vp, &mp, V_WAIT);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_FSYNC(vp, MNT_WAIT, td);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
return (error);
}
bzero(&auio, sizeof(auio));
/*
* Special case for BIO_DELETE. On the surface, this is very
* similar to BIO_WRITE, except that we write from our own
* fixed-length buffer, so we have to loop. The net result is
* that the two cases end up having very little in common.
*/
if (bp->bio_cmd == BIO_DELETE) {
zerosize = ZERO_REGION_SIZE -
(ZERO_REGION_SIZE % sc->sectorsize);
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_rw = UIO_WRITE;
auio.uio_td = td;
end = bp->bio_offset + bp->bio_length;
(void) vn_start_write(vp, &mp, V_WAIT);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = 0;
while (auio.uio_offset < end) {
aiov.iov_base = __DECONST(void *, zero_region);
aiov.iov_len = end - auio.uio_offset;
if (aiov.iov_len > zerosize)
aiov.iov_len = zerosize;
auio.uio_resid = aiov.iov_len;
error = VOP_WRITE(vp, &auio,
sc->flags & MD_ASYNC ? 0 : IO_SYNC, sc->cred);
if (error != 0)
break;
}
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
bp->bio_resid = end - auio.uio_offset;
return (error);
}
KASSERT(bp->bio_length <= MAXPHYS, ("bio_length %jd",
(uintmax_t)bp->bio_length));
if ((bp->bio_flags & BIO_UNMAPPED) == 0) {
pb = NULL;
aiov.iov_base = bp->bio_data;
} else {
pb = getpbuf(&md_vnode_pbuf_freecnt);
pmap_qenter((vm_offset_t)pb->b_data, bp->bio_ma, bp->bio_ma_n);
aiov.iov_base = (void *)((vm_offset_t)pb->b_data +
bp->bio_ma_offset);
}
aiov.iov_len = bp->bio_length;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = (vm_ooffset_t)bp->bio_offset;
auio.uio_segflg = UIO_SYSSPACE;
if (bp->bio_cmd == BIO_READ)
auio.uio_rw = UIO_READ;
else if (bp->bio_cmd == BIO_WRITE)
auio.uio_rw = UIO_WRITE;
else
panic("wrong BIO_OP in mdstart_vnode");
auio.uio_resid = bp->bio_length;
auio.uio_td = td;
/*
* When reading set IO_DIRECT to try to avoid double-caching
* the data. When writing IO_DIRECT is not optimal.
*/
if (bp->bio_cmd == BIO_READ) {
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_READ(vp, &auio, IO_DIRECT, sc->cred);
VOP_UNLOCK(vp, 0);
} else {
(void) vn_start_write(vp, &mp, V_WAIT);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_WRITE(vp, &auio, sc->flags & MD_ASYNC ? 0 : IO_SYNC,
sc->cred);
VOP_UNLOCK(vp, 0);
vn_finished_write(mp);
}
if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
pmap_qremove((vm_offset_t)pb->b_data, bp->bio_ma_n);
relpbuf(pb, &md_vnode_pbuf_freecnt);
}
bp->bio_resid = auio.uio_resid;
return (error);
}
static int
mdstart_swap(struct md_s *sc, struct bio *bp)
{
vm_page_t m;
u_char *p;
vm_pindex_t i, lastp;
int rv, ma_offs, offs, len, lastend;
switch (bp->bio_cmd) {
case BIO_READ:
case BIO_WRITE:
case BIO_DELETE:
break;
default:
return (EOPNOTSUPP);
}
p = bp->bio_data;
ma_offs = (bp->bio_flags & BIO_UNMAPPED) == 0 ? 0 : bp->bio_ma_offset;
/*
* offs is the offset at which to start operating on the
* next (ie, first) page. lastp is the last page on
* which we're going to operate. lastend is the ending
* position within that last page (ie, PAGE_SIZE if
* we're operating on complete aligned pages).
*/
offs = bp->bio_offset % PAGE_SIZE;
lastp = (bp->bio_offset + bp->bio_length - 1) / PAGE_SIZE;
lastend = (bp->bio_offset + bp->bio_length - 1) % PAGE_SIZE + 1;
rv = VM_PAGER_OK;
VM_OBJECT_WLOCK(sc->object);
vm_object_pip_add(sc->object, 1);
for (i = bp->bio_offset / PAGE_SIZE; i <= lastp; i++) {
len = ((i == lastp) ? lastend : PAGE_SIZE) - offs;
m = vm_page_grab(sc->object, i, VM_ALLOC_NORMAL |
VM_ALLOC_RETRY);
if (bp->bio_cmd == BIO_READ) {
if (m->valid == VM_PAGE_BITS_ALL)
rv = VM_PAGER_OK;
else
rv = vm_pager_get_pages(sc->object, &m, 1, 0);
if (rv == VM_PAGER_ERROR) {
vm_page_wakeup(m);
break;
} else if (rv == VM_PAGER_FAIL) {
/*
* Pager does not have the page. Zero
* the allocated page, and mark it as
* valid. Do not set dirty, the page
* can be recreated if thrown out.
*/
pmap_zero_page(m);
m->valid = VM_PAGE_BITS_ALL;
}
if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
pmap_copy_pages(&m, offs, bp->bio_ma,
ma_offs, len);
} else {
physcopyout(VM_PAGE_TO_PHYS(m) + offs, p, len);
cpu_flush_dcache(p, len);
}
} else if (bp->bio_cmd == BIO_WRITE) {
if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
rv = vm_pager_get_pages(sc->object, &m, 1, 0);
else
rv = VM_PAGER_OK;
if (rv == VM_PAGER_ERROR) {
vm_page_wakeup(m);
break;
}
if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
pmap_copy_pages(bp->bio_ma, ma_offs, &m,
offs, len);
} else {
physcopyin(p, VM_PAGE_TO_PHYS(m) + offs, len);
}
m->valid = VM_PAGE_BITS_ALL;
} else if (bp->bio_cmd == BIO_DELETE) {
if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
rv = vm_pager_get_pages(sc->object, &m, 1, 0);
else
rv = VM_PAGER_OK;
if (rv == VM_PAGER_ERROR) {
vm_page_wakeup(m);
break;
}
if (len != PAGE_SIZE) {
pmap_zero_page_area(m, offs, len);
vm_page_clear_dirty(m, offs, len);
m->valid = VM_PAGE_BITS_ALL;
} else
vm_pager_page_unswapped(m);
}
vm_page_wakeup(m);
vm_page_lock(m);
if (bp->bio_cmd == BIO_DELETE && len == PAGE_SIZE)
vm_page_free(m);
else
vm_page_activate(m);
vm_page_unlock(m);
if (bp->bio_cmd == BIO_WRITE)
vm_page_dirty(m);
/* Actions on further pages start at offset 0 */
p += PAGE_SIZE - offs;
offs = 0;
ma_offs += len;
}
vm_object_pip_subtract(sc->object, 1);
VM_OBJECT_WUNLOCK(sc->object);
return (rv != VM_PAGER_ERROR ? 0 : ENOSPC);
}
static void
md_kthread(void *arg)
{
struct md_s *sc;
struct bio *bp;
int error;
sc = arg;
thread_lock(curthread);
sched_prio(curthread, PRIBIO);
thread_unlock(curthread);
if (sc->type == MD_VNODE)
curthread->td_pflags |= TDP_NORUNNINGBUF;
for (;;) {
mtx_lock(&sc->queue_mtx);
if (sc->flags & MD_SHUTDOWN) {
sc->flags |= MD_EXITING;
mtx_unlock(&sc->queue_mtx);
kproc_exit(0);
}
bp = bioq_takefirst(&sc->bio_queue);
if (!bp) {
msleep(sc, &sc->queue_mtx, PRIBIO | PDROP, "mdwait", 0);
continue;
}
mtx_unlock(&sc->queue_mtx);
if (bp->bio_cmd == BIO_GETATTR) {
if ((sc->fwsectors && sc->fwheads &&
(g_handleattr_int(bp, "GEOM::fwsectors",
sc->fwsectors) ||
g_handleattr_int(bp, "GEOM::fwheads",
sc->fwheads))) ||
g_handleattr_int(bp, "GEOM::candelete", 1))
error = -1;
else
error = EOPNOTSUPP;
} else {
error = sc->start(sc, bp);
}
if (error != -1) {
bp->bio_completed = bp->bio_length;
if ((bp->bio_cmd == BIO_READ) || (bp->bio_cmd == BIO_WRITE))
devstat_end_transaction_bio(sc->devstat, bp);
g_io_deliver(bp, error);
}
}
}
static struct md_s *
mdfind(int unit)
{
struct md_s *sc;
LIST_FOREACH(sc, &md_softc_list, list) {
if (sc->unit == unit)
break;
}
return (sc);
}
static struct md_s *
mdnew(int unit, int *errp, enum md_types type)
{
struct md_s *sc;
int error;
*errp = 0;
if (unit == -1)
unit = alloc_unr(md_uh);
else
unit = alloc_unr_specific(md_uh, unit);
if (unit == -1) {
*errp = EBUSY;
return (NULL);
}
sc = (struct md_s *)malloc(sizeof *sc, M_MD, M_WAITOK | M_ZERO);
sc->type = type;
bioq_init(&sc->bio_queue);
mtx_init(&sc->queue_mtx, "md bio queue", NULL, MTX_DEF);
sc->unit = unit;
sprintf(sc->name, "md%d", unit);
LIST_INSERT_HEAD(&md_softc_list, sc, list);
error = kproc_create(md_kthread, sc, &sc->procp, 0, 0,"%s", sc->name);
if (error == 0)
return (sc);
LIST_REMOVE(sc, list);
mtx_destroy(&sc->queue_mtx);
free_unr(md_uh, sc->unit);
free(sc, M_MD);
*errp = error;
return (NULL);
}
static void
mdinit(struct md_s *sc)
{
struct g_geom *gp;
struct g_provider *pp;
g_topology_lock();
gp = g_new_geomf(&g_md_class, "md%d", sc->unit);
gp->softc = sc;
pp = g_new_providerf(gp, "md%d", sc->unit);
pp->mediasize = sc->mediasize;
pp->sectorsize = sc->sectorsize;
switch (sc->type) {
case MD_MALLOC:
case MD_VNODE:
case MD_SWAP:
pp->flags |= G_PF_ACCEPT_UNMAPPED;
break;
case MD_PRELOAD:
break;
}
sc->gp = gp;
sc->pp = pp;
g_error_provider(pp, 0);
g_topology_unlock();
sc->devstat = devstat_new_entry("md", sc->unit, sc->sectorsize,
DEVSTAT_ALL_SUPPORTED, DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
}
static int
mdcreate_malloc(struct md_s *sc, struct md_ioctl *mdio)
{
uintptr_t sp;
int error;
off_t u;
error = 0;
if (mdio->md_options & ~(MD_AUTOUNIT | MD_COMPRESS | MD_RESERVE))
return (EINVAL);
if (mdio->md_sectorsize != 0 && !powerof2(mdio->md_sectorsize))
return (EINVAL);
/* Compression doesn't make sense if we have reserved space */
if (mdio->md_options & MD_RESERVE)
mdio->md_options &= ~MD_COMPRESS;
if (mdio->md_fwsectors != 0)
sc->fwsectors = mdio->md_fwsectors;
if (mdio->md_fwheads != 0)
sc->fwheads = mdio->md_fwheads;
sc->flags = mdio->md_options & (MD_COMPRESS | MD_FORCE);
sc->indir = dimension(sc->mediasize / sc->sectorsize);
sc->uma = uma_zcreate(sc->name, sc->sectorsize, NULL, NULL, NULL, NULL,
0x1ff, 0);
if (mdio->md_options & MD_RESERVE) {
off_t nsectors;
nsectors = sc->mediasize / sc->sectorsize;
for (u = 0; u < nsectors; u++) {
sp = (uintptr_t)uma_zalloc(sc->uma, (md_malloc_wait ?
M_WAITOK : M_NOWAIT) | M_ZERO);
if (sp != 0)
error = s_write(sc->indir, u, sp);
else
error = ENOMEM;
if (error != 0)
break;
}
}
return (error);
}
static int
mdsetcred(struct md_s *sc, struct ucred *cred)
{
char *tmpbuf;
int error = 0;
/*
* Set credits in our softc
*/
if (sc->cred)
crfree(sc->cred);
sc->cred = crhold(cred);
/*
* Horrible kludge to establish credentials for NFS XXX.
*/
if (sc->vnode) {
struct uio auio;
struct iovec aiov;
tmpbuf = malloc(sc->sectorsize, M_TEMP, M_WAITOK);
bzero(&auio, sizeof(auio));
aiov.iov_base = tmpbuf;
aiov.iov_len = sc->sectorsize;
auio.uio_iov = &aiov;
auio.uio_iovcnt = 1;
auio.uio_offset = 0;
auio.uio_rw = UIO_READ;
auio.uio_segflg = UIO_SYSSPACE;
auio.uio_resid = aiov.iov_len;
vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY);
error = VOP_READ(sc->vnode, &auio, 0, sc->cred);
VOP_UNLOCK(sc->vnode, 0);
free(tmpbuf, M_TEMP);
}
return (error);
}
static int
mdcreate_vnode(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
{
struct vattr vattr;
struct nameidata nd;
char *fname;
int error, flags;
/*
* Kernel-originated requests must have the filename appended
* to the mdio structure to protect against malicious software.
*/
fname = mdio->md_file;
if ((void *)fname != (void *)(mdio + 1)) {
error = copyinstr(fname, sc->file, sizeof(sc->file), NULL);
if (error != 0)
return (error);
} else
strlcpy(sc->file, fname, sizeof(sc->file));
/*
* If the user specified that this is a read only device, don't
* set the FWRITE mask before trying to open the backing store.
*/
flags = FREAD | ((mdio->md_options & MD_READONLY) ? 0 : FWRITE);
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, sc->file, td);
error = vn_open(&nd, &flags, 0, NULL);
if (error != 0)
return (error);
NDFREE(&nd, NDF_ONLY_PNBUF);
if (nd.ni_vp->v_type != VREG) {
error = EINVAL;
goto bad;
}
error = VOP_GETATTR(nd.ni_vp, &vattr, td->td_ucred);
if (error != 0)
goto bad;
if (VOP_ISLOCKED(nd.ni_vp) != LK_EXCLUSIVE) {
vn_lock(nd.ni_vp, LK_UPGRADE | LK_RETRY);
if (nd.ni_vp->v_iflag & VI_DOOMED) {
/* Forced unmount. */
error = EBADF;
goto bad;
}
}
nd.ni_vp->v_vflag |= VV_MD;
VOP_UNLOCK(nd.ni_vp, 0);
if (mdio->md_fwsectors != 0)
sc->fwsectors = mdio->md_fwsectors;
if (mdio->md_fwheads != 0)
sc->fwheads = mdio->md_fwheads;
sc->flags = mdio->md_options & (MD_FORCE | MD_ASYNC);
if (!(flags & FWRITE))
sc->flags |= MD_READONLY;
sc->vnode = nd.ni_vp;
error = mdsetcred(sc, td->td_ucred);
if (error != 0) {
sc->vnode = NULL;
vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
nd.ni_vp->v_vflag &= ~VV_MD;
goto bad;
}
return (0);
bad:
VOP_UNLOCK(nd.ni_vp, 0);
(void)vn_close(nd.ni_vp, flags, td->td_ucred, td);
return (error);
}
static int
mddestroy(struct md_s *sc, struct thread *td)
{
if (sc->gp) {
sc->gp->softc = NULL;
g_topology_lock();
g_wither_geom(sc->gp, ENXIO);
g_topology_unlock();
sc->gp = NULL;
sc->pp = NULL;
}
if (sc->devstat) {
devstat_remove_entry(sc->devstat);
sc->devstat = NULL;
}
mtx_lock(&sc->queue_mtx);
sc->flags |= MD_SHUTDOWN;
wakeup(sc);
while (!(sc->flags & MD_EXITING))
msleep(sc->procp, &sc->queue_mtx, PRIBIO, "mddestroy", hz / 10);
mtx_unlock(&sc->queue_mtx);
mtx_destroy(&sc->queue_mtx);
if (sc->vnode != NULL) {
vn_lock(sc->vnode, LK_EXCLUSIVE | LK_RETRY);
sc->vnode->v_vflag &= ~VV_MD;
VOP_UNLOCK(sc->vnode, 0);
(void)vn_close(sc->vnode, sc->flags & MD_READONLY ?
FREAD : (FREAD|FWRITE), sc->cred, td);
}
if (sc->cred != NULL)
crfree(sc->cred);
if (sc->object != NULL)
vm_object_deallocate(sc->object);
if (sc->indir)
destroy_indir(sc, sc->indir);
if (sc->uma)
uma_zdestroy(sc->uma);
LIST_REMOVE(sc, list);
free_unr(md_uh, sc->unit);
free(sc, M_MD);
return (0);
}
static int
mdresize(struct md_s *sc, struct md_ioctl *mdio)
{
int error, res;
vm_pindex_t oldpages, newpages;
switch (sc->type) {
case MD_VNODE:
break;
case MD_SWAP:
if (mdio->md_mediasize <= 0 ||
(mdio->md_mediasize % PAGE_SIZE) != 0)
return (EDOM);
oldpages = OFF_TO_IDX(round_page(sc->mediasize));
newpages = OFF_TO_IDX(round_page(mdio->md_mediasize));
if (newpages < oldpages) {
VM_OBJECT_WLOCK(sc->object);
vm_object_page_remove(sc->object, newpages, 0, 0);
swap_pager_freespace(sc->object, newpages,
oldpages - newpages);
swap_release_by_cred(IDX_TO_OFF(oldpages -
newpages), sc->cred);
sc->object->charge = IDX_TO_OFF(newpages);
sc->object->size = newpages;
VM_OBJECT_WUNLOCK(sc->object);
} else if (newpages > oldpages) {
res = swap_reserve_by_cred(IDX_TO_OFF(newpages -
oldpages), sc->cred);
if (!res)
return (ENOMEM);
if ((mdio->md_options & MD_RESERVE) ||
(sc->flags & MD_RESERVE)) {
error = swap_pager_reserve(sc->object,
oldpages, newpages - oldpages);
if (error < 0) {
swap_release_by_cred(
IDX_TO_OFF(newpages - oldpages),
sc->cred);
return (EDOM);
}
}
VM_OBJECT_WLOCK(sc->object);
sc->object->charge = IDX_TO_OFF(newpages);
sc->object->size = newpages;
VM_OBJECT_WUNLOCK(sc->object);
}
break;
default:
return (EOPNOTSUPP);
}
sc->mediasize = mdio->md_mediasize;
g_topology_lock();
g_resize_provider(sc->pp, sc->mediasize);
g_topology_unlock();
return (0);
}
static int
mdcreate_swap(struct md_s *sc, struct md_ioctl *mdio, struct thread *td)
{
vm_ooffset_t npage;
int error;
/*
* Range check. Disallow negative sizes or any size less then the
* size of a page. Then round to a page.
*/
if (sc->mediasize <= 0 || (sc->mediasize % PAGE_SIZE) != 0)
return (EDOM);
/*
* Allocate an OBJT_SWAP object.
*
* Note the truncation.
*/
npage = mdio->md_mediasize / PAGE_SIZE;
if (mdio->md_fwsectors != 0)
sc->fwsectors = mdio->md_fwsectors;
if (mdio->md_fwheads != 0)
sc->fwheads = mdio->md_fwheads;
sc->object = vm_pager_allocate(OBJT_SWAP, NULL, PAGE_SIZE * npage,
VM_PROT_DEFAULT, 0, td->td_ucred);
if (sc->object == NULL)
return (ENOMEM);
sc->flags = mdio->md_options & (MD_FORCE | MD_RESERVE);
if (mdio->md_options & MD_RESERVE) {
if (swap_pager_reserve(sc->object, 0, npage) < 0) {
error = EDOM;
goto finish;
}
}
error = mdsetcred(sc, td->td_ucred);
finish:
if (error != 0) {
vm_object_deallocate(sc->object);
sc->object = NULL;
}
return (error);
}
static int
xmdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
{
struct md_ioctl *mdio;
struct md_s *sc;
int error, i;
unsigned sectsize;
if (md_debug)
printf("mdctlioctl(%s %lx %p %x %p)\n",
devtoname(dev), cmd, addr, flags, td);
mdio = (struct md_ioctl *)addr;
if (mdio->md_version != MDIOVERSION)
return (EINVAL);
/*
* We assert the version number in the individual ioctl
* handlers instead of out here because (a) it is possible we
* may add another ioctl in the future which doesn't read an
* mdio, and (b) the correct return value for an unknown ioctl
* is ENOIOCTL, not EINVAL.
*/
error = 0;
switch (cmd) {
case MDIOCATTACH:
switch (mdio->md_type) {
case MD_MALLOC:
case MD_PRELOAD:
case MD_VNODE:
case MD_SWAP:
break;
default:
return (EINVAL);
}
if (mdio->md_sectorsize == 0)
sectsize = DEV_BSIZE;
else
sectsize = mdio->md_sectorsize;
if (sectsize > MAXPHYS || mdio->md_mediasize < sectsize)
return (EINVAL);
if (mdio->md_options & MD_AUTOUNIT)
sc = mdnew(-1, &error, mdio->md_type);
else {
if (mdio->md_unit > INT_MAX)
return (EINVAL);
sc = mdnew(mdio->md_unit, &error, mdio->md_type);
}
if (sc == NULL)
return (error);
if (mdio->md_options & MD_AUTOUNIT)
mdio->md_unit = sc->unit;
sc->mediasize = mdio->md_mediasize;
sc->sectorsize = sectsize;
error = EDOOFUS;
switch (sc->type) {
case MD_MALLOC:
sc->start = mdstart_malloc;
error = mdcreate_malloc(sc, mdio);
break;
case MD_PRELOAD:
/*
* We disallow attaching preloaded memory disks via
* ioctl. Preloaded memory disks are automatically
* attached in g_md_init().
*/
error = EOPNOTSUPP;
break;
case MD_VNODE:
sc->start = mdstart_vnode;
error = mdcreate_vnode(sc, mdio, td);
break;
case MD_SWAP:
sc->start = mdstart_swap;
error = mdcreate_swap(sc, mdio, td);
break;
}
if (error != 0) {
mddestroy(sc, td);
return (error);
}
/* Prune off any residual fractional sector */
i = sc->mediasize % sc->sectorsize;
sc->mediasize -= i;
mdinit(sc);
return (0);
case MDIOCDETACH:
if (mdio->md_mediasize != 0 ||
(mdio->md_options & ~MD_FORCE) != 0)
return (EINVAL);
sc = mdfind(mdio->md_unit);
if (sc == NULL)
return (ENOENT);
if (sc->opencount != 0 && !(sc->flags & MD_FORCE) &&
!(mdio->md_options & MD_FORCE))
return (EBUSY);
return (mddestroy(sc, td));
case MDIOCRESIZE:
if ((mdio->md_options & ~(MD_FORCE | MD_RESERVE)) != 0)
return (EINVAL);
sc = mdfind(mdio->md_unit);
if (sc == NULL)
return (ENOENT);
if (mdio->md_mediasize < sc->sectorsize)
return (EINVAL);
if (mdio->md_mediasize < sc->mediasize &&
!(sc->flags & MD_FORCE) &&
!(mdio->md_options & MD_FORCE))
return (EBUSY);
return (mdresize(sc, mdio));
case MDIOCQUERY:
sc = mdfind(mdio->md_unit);
if (sc == NULL)
return (ENOENT);
mdio->md_type = sc->type;
mdio->md_options = sc->flags;
mdio->md_mediasize = sc->mediasize;
mdio->md_sectorsize = sc->sectorsize;
if (sc->type == MD_VNODE)
error = copyout(sc->file, mdio->md_file,
strlen(sc->file) + 1);
return (error);
case MDIOCLIST:
i = 1;
LIST_FOREACH(sc, &md_softc_list, list) {
if (i == MDNPAD - 1)
mdio->md_pad[i] = -1;
else
mdio->md_pad[i++] = sc->unit;
}
mdio->md_pad[0] = i - 1;
return (0);
default:
return (ENOIOCTL);
};
}
static int
mdctlioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, struct thread *td)
{
int error;
sx_xlock(&md_sx);
error = xmdctlioctl(dev, cmd, addr, flags, td);
sx_xunlock(&md_sx);
return (error);
}
static void
md_preloaded(u_char *image, size_t length, const char *name)
{
struct md_s *sc;
int error;
sc = mdnew(-1, &error, MD_PRELOAD);
if (sc == NULL)
return;
sc->mediasize = length;
sc->sectorsize = DEV_BSIZE;
sc->pl_ptr = image;
sc->pl_len = length;
sc->start = mdstart_preload;
#ifdef MD_ROOT
if (sc->unit == 0)
rootdevnames[0] = MD_ROOT_FSTYPE ":/dev/md0";
#endif
mdinit(sc);
if (name != NULL) {
printf("%s%d: Preloaded image <%s> %zd bytes at %p\n",
MD_NAME, sc->unit, name, length, image);
}
}
static void
g_md_init(struct g_class *mp __unused)
{
caddr_t mod;
u_char *ptr, *name, *type;
unsigned len;
int i;
/* figure out log2(NINDIR) */
for (i = NINDIR, nshift = -1; i; nshift++)
i >>= 1;
mod = NULL;
sx_init(&md_sx, "MD config lock");
g_topology_unlock();
md_uh = new_unrhdr(0, INT_MAX, NULL);
#ifdef MD_ROOT_SIZE
sx_xlock(&md_sx);
md_preloaded(mfs_root.start, sizeof(mfs_root.start), NULL);
sx_xunlock(&md_sx);
#endif
/* XXX: are preload_* static or do they need Giant ? */
while ((mod = preload_search_next_name(mod)) != NULL) {
name = (char *)preload_search_info(mod, MODINFO_NAME);
if (name == NULL)
continue;
type = (char *)preload_search_info(mod, MODINFO_TYPE);
if (type == NULL)
continue;
if (strcmp(type, "md_image") && strcmp(type, "mfs_root"))
continue;
ptr = preload_fetch_addr(mod);
len = preload_fetch_size(mod);
if (ptr != NULL && len != 0) {
sx_xlock(&md_sx);
md_preloaded(ptr, len, name);
sx_xunlock(&md_sx);
}
}
md_vnode_pbuf_freecnt = nswbuf / 10;
status_dev = make_dev(&mdctl_cdevsw, INT_MAX, UID_ROOT, GID_WHEEL,
0600, MDCTL_NAME);
g_topology_lock();
}
static void
g_md_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
struct g_consumer *cp __unused, struct g_provider *pp)
{
struct md_s *mp;
char *type;
mp = gp->softc;
if (mp == NULL)
return;
switch (mp->type) {
case MD_MALLOC:
type = "malloc";
break;
case MD_PRELOAD:
type = "preload";
break;
case MD_VNODE:
type = "vnode";
break;
case MD_SWAP:
type = "swap";
break;
default:
type = "unknown";
break;
}
if (pp != NULL) {
if (indent == NULL) {
sbuf_printf(sb, " u %d", mp->unit);
sbuf_printf(sb, " s %ju", (uintmax_t) mp->sectorsize);
sbuf_printf(sb, " f %ju", (uintmax_t) mp->fwheads);
sbuf_printf(sb, " fs %ju", (uintmax_t) mp->fwsectors);
sbuf_printf(sb, " l %ju", (uintmax_t) mp->mediasize);
sbuf_printf(sb, " t %s", type);
if (mp->type == MD_VNODE && mp->vnode != NULL)
sbuf_printf(sb, " file %s", mp->file);
} else {
sbuf_printf(sb, "%s<unit>%d</unit>\n", indent,
mp->unit);
sbuf_printf(sb, "%s<sectorsize>%ju</sectorsize>\n",
indent, (uintmax_t) mp->sectorsize);
sbuf_printf(sb, "%s<fwheads>%ju</fwheads>\n",
indent, (uintmax_t) mp->fwheads);
sbuf_printf(sb, "%s<fwsectors>%ju</fwsectors>\n",
indent, (uintmax_t) mp->fwsectors);
sbuf_printf(sb, "%s<length>%ju</length>\n",
indent, (uintmax_t) mp->mediasize);
sbuf_printf(sb, "%s<compression>%s</compression>\n", indent,
(mp->flags & MD_COMPRESS) == 0 ? "off": "on");
sbuf_printf(sb, "%s<access>%s</access>\n", indent,
(mp->flags & MD_READONLY) == 0 ? "read-write":
"read-only");
sbuf_printf(sb, "%s<type>%s</type>\n", indent,
type);
if (mp->type == MD_VNODE && mp->vnode != NULL)
sbuf_printf(sb, "%s<file>%s</file>\n",
indent, mp->file);
}
}
}
static void
g_md_fini(struct g_class *mp __unused)
{
sx_destroy(&md_sx);
if (status_dev != NULL)
destroy_dev(status_dev);
delete_unrhdr(md_uh);
}