freebsd-dev/sys/geom/geom_disk.c
John Polstra a7e69e8b7d Fix a bug that caused some /dev entries to continue to exist after
the underlying drive had been hot-unplugged from the system.  Here
is a specific example.  Filesystem code had opened /dev/da1s1e.
Subsequently, the drive was hot-unplugged.  This (correctly) caused
all of the associated /dev/da1* entries to be deleted.  When the
filesystem later realized that the drive was gone it closed the
device, reducing the write-access counts to 0 on the geom providers
for da1s1e, da1s1, and da1.  This caused geom to re-taste the
providers, resulting in the devices being created again.  When the
drive was hot-plugged back in, it resulted in duplicate /dev entries
for da1s1e, da1s1, and da1.

This fix adds a new disk_gone() function which is called by CAM when a
drive goes away.  It orphans all of the providers associated with the
drive, setting an error condition of ENXIO in each one.  In addition,
we prevent a re-taste on last close for writing if an error condition
has been set in the provider.

Sponsored by:   Isilon Systems
Reviewed by:    phk
MFC after:      1 week
2005-11-18 02:43:49 +00:00

467 lines
11 KiB
C

/*-
* Copyright (c) 2002 Poul-Henning Kamp
* Copyright (c) 2002 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Poul-Henning Kamp
* and NAI Labs, the Security Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* 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.
* 3. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_geom.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/bio.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/sysctl.h>
#include <sys/devicestat.h>
#include <machine/md_var.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <geom/geom.h>
#include <geom/geom_disk.h>
#include <geom/geom_int.h>
static struct mtx g_disk_done_mtx;
static g_access_t g_disk_access;
static g_init_t g_disk_init;
static g_fini_t g_disk_fini;
static g_start_t g_disk_start;
static g_ioctl_t g_disk_ioctl;
static g_dumpconf_t g_disk_dumpconf;
static struct g_class g_disk_class = {
.name = "DISK",
.version = G_VERSION,
.init = g_disk_init,
.fini = g_disk_fini,
.start = g_disk_start,
.access = g_disk_access,
.ioctl = g_disk_ioctl,
.dumpconf = g_disk_dumpconf,
};
static void
g_disk_init(struct g_class *mp __unused)
{
mtx_init(&g_disk_done_mtx, "g_disk_done", NULL, MTX_DEF);
}
static void
g_disk_fini(struct g_class *mp __unused)
{
mtx_destroy(&g_disk_done_mtx);
}
DECLARE_GEOM_CLASS(g_disk_class, g_disk);
static void __inline
g_disk_lock_giant(struct disk *dp)
{
if (dp->d_flags & DISKFLAG_NEEDSGIANT)
mtx_lock(&Giant);
}
static void __inline
g_disk_unlock_giant(struct disk *dp)
{
if (dp->d_flags & DISKFLAG_NEEDSGIANT)
mtx_unlock(&Giant);
}
static int
g_disk_access(struct g_provider *pp, int r, int w, int e)
{
struct disk *dp;
int error;
g_trace(G_T_ACCESS, "g_disk_access(%s, %d, %d, %d)",
pp->name, r, w, e);
g_topology_assert();
dp = pp->geom->softc;
if (dp == NULL || dp->d_destroyed) {
/*
* Allow decreasing access count even if disk is not
* avaliable anymore.
*/
if (r <= 0 && w <= 0 && e <= 0)
return (0);
return (ENXIO);
}
r += pp->acr;
w += pp->acw;
e += pp->ace;
error = 0;
if ((pp->acr + pp->acw + pp->ace) == 0 && (r + w + e) > 0) {
if (dp->d_open != NULL) {
g_disk_lock_giant(dp);
error = dp->d_open(dp);
if (error != 0)
printf("Opened disk %s -> %d\n",
pp->name, error);
g_disk_unlock_giant(dp);
}
pp->mediasize = dp->d_mediasize;
pp->sectorsize = dp->d_sectorsize;
dp->d_flags |= DISKFLAG_OPEN;
if (dp->d_maxsize == 0) {
printf("WARNING: Disk drive %s%d has no d_maxsize\n",
dp->d_name, dp->d_unit);
dp->d_maxsize = DFLTPHYS;
}
} else if ((pp->acr + pp->acw + pp->ace) > 0 && (r + w + e) == 0) {
if (dp->d_close != NULL) {
g_disk_lock_giant(dp);
error = dp->d_close(dp);
if (error != 0)
printf("Closed disk %s -> %d\n",
pp->name, error);
g_disk_unlock_giant(dp);
}
dp->d_flags &= ~DISKFLAG_OPEN;
}
return (error);
}
static void
g_disk_kerneldump(struct bio *bp, struct disk *dp)
{
int error;
struct g_kerneldump *gkd;
struct dumperinfo di;
struct g_geom *gp;
gkd = (struct g_kerneldump*)bp->bio_data;
gp = bp->bio_to->geom;
g_trace(G_T_TOPOLOGY, "g_disk_kernedump(%s, %jd, %jd)",
gp->name, (intmax_t)gkd->offset, (intmax_t)gkd->length);
if (dp->d_dump == NULL) {
g_io_deliver(bp, ENODEV);
return;
}
di.dumper = dp->d_dump;
di.priv = dp;
di.blocksize = dp->d_sectorsize;
di.mediaoffset = gkd->offset;
if ((gkd->offset + gkd->length) > dp->d_mediasize)
gkd->length = dp->d_mediasize - gkd->offset;
di.mediasize = gkd->length;
error = set_dumper(&di);
g_io_deliver(bp, error);
}
static void
g_disk_done(struct bio *bp)
{
struct bio *bp2;
struct disk *dp;
/* See "notes" for why we need a mutex here */
/* XXX: will witness accept a mix of Giant/unGiant drivers here ? */
mtx_lock(&g_disk_done_mtx);
bp->bio_completed = bp->bio_length - bp->bio_resid;
bp2 = bp->bio_parent;
if (bp2->bio_error == 0)
bp2->bio_error = bp->bio_error;
bp2->bio_completed += bp->bio_completed;
if ((dp = bp2->bio_to->geom->softc))
devstat_end_transaction_bio(dp->d_devstat, bp);
g_destroy_bio(bp);
bp2->bio_inbed++;
if (bp2->bio_children == bp2->bio_inbed) {
bp2->bio_resid = bp2->bio_bcount - bp2->bio_completed;
g_io_deliver(bp2, bp2->bio_error);
}
mtx_unlock(&g_disk_done_mtx);
}
static int
g_disk_ioctl(struct g_provider *pp, u_long cmd, void * data, int fflag, struct thread *td)
{
struct g_geom *gp;
struct disk *dp;
int error;
gp = pp->geom;
dp = gp->softc;
if (dp->d_ioctl == NULL)
return (ENOIOCTL);
g_disk_lock_giant(dp);
error = dp->d_ioctl(dp, cmd, data, fflag, td);
g_disk_unlock_giant(dp);
return(error);
}
static void
g_disk_start(struct bio *bp)
{
struct bio *bp2, *bp3;
struct disk *dp;
int error;
off_t off;
dp = bp->bio_to->geom->softc;
if (dp == NULL || dp->d_destroyed) {
g_io_deliver(bp, ENXIO);
return;
}
error = EJUSTRETURN;
switch(bp->bio_cmd) {
case BIO_DELETE:
if (!(dp->d_flags & DISKFLAG_CANDELETE)) {
error = 0;
break;
}
/* fall-through */
case BIO_READ:
case BIO_WRITE:
off = 0;
bp3 = NULL;
bp2 = g_clone_bio(bp);
if (bp2 == NULL) {
error = ENOMEM;
break;
}
do {
bp2->bio_offset += off;
bp2->bio_length -= off;
bp2->bio_data += off;
if (bp2->bio_length > dp->d_maxsize) {
/*
* XXX: If we have a stripesize we should really
* use it here.
*/
bp2->bio_length = dp->d_maxsize;
off += dp->d_maxsize;
/*
* To avoid a race, we need to grab the next bio
* before we schedule this one. See "notes".
*/
bp3 = g_clone_bio(bp);
if (bp3 == NULL)
bp->bio_error = ENOMEM;
}
bp2->bio_done = g_disk_done;
bp2->bio_pblkno = bp2->bio_offset / dp->d_sectorsize;
bp2->bio_bcount = bp2->bio_length;
bp2->bio_disk = dp;
devstat_start_transaction_bio(dp->d_devstat, bp2);
g_disk_lock_giant(dp);
dp->d_strategy(bp2);
g_disk_unlock_giant(dp);
bp2 = bp3;
bp3 = NULL;
} while (bp2 != NULL);
break;
case BIO_GETATTR:
if (g_handleattr_int(bp, "GEOM::fwsectors", dp->d_fwsectors))
break;
else if (g_handleattr_int(bp, "GEOM::fwheads", dp->d_fwheads))
break;
else if (g_handleattr_off_t(bp, "GEOM::frontstuff", 0))
break;
else if (!strcmp(bp->bio_attribute, "GEOM::kerneldump"))
g_disk_kerneldump(bp, dp);
else
error = ENOIOCTL;
break;
default:
error = EOPNOTSUPP;
break;
}
if (error != EJUSTRETURN)
g_io_deliver(bp, error);
return;
}
static void
g_disk_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp)
{
struct disk *dp;
dp = gp->softc;
if (dp == NULL)
return;
if (indent == NULL) {
sbuf_printf(sb, " hd %u", dp->d_fwheads);
sbuf_printf(sb, " sc %u", dp->d_fwsectors);
return;
}
if (pp != NULL) {
sbuf_printf(sb, "%s<fwheads>%u</fwheads>\n",
indent, dp->d_fwheads);
sbuf_printf(sb, "%s<fwsectors>%u</fwsectors>\n",
indent, dp->d_fwsectors);
}
}
static void
g_disk_create(void *arg, int flag)
{
struct g_geom *gp;
struct g_provider *pp;
struct disk *dp;
if (flag == EV_CANCEL)
return;
g_topology_assert();
dp = arg;
gp = g_new_geomf(&g_disk_class, "%s%d", dp->d_name, dp->d_unit);
gp->softc = dp;
pp = g_new_providerf(gp, "%s", gp->name);
pp->mediasize = dp->d_mediasize;
pp->sectorsize = dp->d_sectorsize;
if (dp->d_flags & DISKFLAG_CANDELETE)
pp->flags |= G_PF_CANDELETE;
pp->stripeoffset = dp->d_stripeoffset;
pp->stripesize = dp->d_stripesize;
if (bootverbose)
printf("GEOM: new disk %s\n", gp->name);
dp->d_geom = gp;
g_error_provider(pp, 0);
}
static void
g_disk_destroy(void *ptr, int flag)
{
struct disk *dp;
struct g_geom *gp;
g_topology_assert();
dp = ptr;
gp = dp->d_geom;
if (gp != NULL) {
gp->softc = NULL;
g_wither_geom(gp, ENXIO);
}
g_free(dp);
}
struct disk *
disk_alloc()
{
struct disk *dp;
dp = g_malloc(sizeof *dp, M_WAITOK | M_ZERO);
return (dp);
}
void
disk_create(struct disk *dp, int version)
{
if (version != DISK_VERSION_00) {
printf("WARNING: Attempt to add disk %s%d %s",
dp->d_name, dp->d_unit,
" using incompatible ABI version of disk(9)\n");
printf("WARNING: Ignoring disk %s%d\n",
dp->d_name, dp->d_unit);
return;
}
KASSERT(dp->d_strategy != NULL, ("disk_create need d_strategy"));
KASSERT(dp->d_name != NULL, ("disk_create need d_name"));
KASSERT(*dp->d_name != 0, ("disk_create need d_name"));
KASSERT(strlen(dp->d_name) < SPECNAMELEN - 4, ("disk name too long"));
if (dp->d_devstat == NULL)
dp->d_devstat = devstat_new_entry(dp->d_name, dp->d_unit,
dp->d_sectorsize, DEVSTAT_ALL_SUPPORTED,
DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX);
dp->d_geom = NULL;
g_post_event(g_disk_create, dp, M_WAITOK, dp, NULL);
}
void
disk_destroy(struct disk *dp)
{
g_cancel_event(dp);
dp->d_destroyed = 1;
if (dp->d_devstat != NULL)
devstat_remove_entry(dp->d_devstat);
g_post_event(g_disk_destroy, dp, M_WAITOK, NULL);
}
void
disk_gone(struct disk *dp)
{
struct g_geom *gp;
struct g_provider *pp;
gp = dp->d_geom;
if (gp != NULL)
LIST_FOREACH(pp, &gp->provider, provider)
g_orphan_provider(pp, ENXIO);
}
static void
g_kern_disks(void *p, int flag __unused)
{
struct sbuf *sb;
struct g_geom *gp;
char *sp;
sb = p;
sp = "";
g_topology_assert();
LIST_FOREACH(gp, &g_disk_class.geom, geom) {
sbuf_printf(sb, "%s%s", sp, gp->name);
sp = " ";
}
sbuf_finish(sb);
}
static int
sysctl_disks(SYSCTL_HANDLER_ARGS)
{
int error;
struct sbuf *sb;
sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND);
g_waitfor_event(g_kern_disks, sb, M_WAITOK, NULL);
error = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb) + 1);
sbuf_delete(sb);
return error;
}
SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NOLOCK, 0, 0,
sysctl_disks, "A", "names of available disks");