freebsd-dev/sys/geom/geom_dev.c
Conrad Meyer b4d7290796 geom_dev: Use kenv 'dumpdev' in the same way as rc/etc.d/dumpon
Skip a /dev/ prefix, if one is present, when checking for matching
device names for dump.

Suggested by:	avg
Reviewed by:	markj
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D3725
2015-09-23 21:08:52 +00:00

719 lines
18 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 <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/ctype.h>
#include <sys/bio.h>
#include <sys/bus.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/disk.h>
#include <sys/fcntl.h>
#include <sys/limits.h>
#include <sys/sysctl.h>
#include <geom/geom.h>
#include <geom/geom_int.h>
#include <machine/stdarg.h>
struct g_dev_softc {
struct mtx sc_mtx;
struct cdev *sc_dev;
struct cdev *sc_alias;
int sc_open;
int sc_active;
};
static d_open_t g_dev_open;
static d_close_t g_dev_close;
static d_strategy_t g_dev_strategy;
static d_ioctl_t g_dev_ioctl;
static struct cdevsw g_dev_cdevsw = {
.d_version = D_VERSION,
.d_open = g_dev_open,
.d_close = g_dev_close,
.d_read = physread,
.d_write = physwrite,
.d_ioctl = g_dev_ioctl,
.d_strategy = g_dev_strategy,
.d_name = "g_dev",
.d_flags = D_DISK | D_TRACKCLOSE,
};
static g_init_t g_dev_init;
static g_fini_t g_dev_fini;
static g_taste_t g_dev_taste;
static g_orphan_t g_dev_orphan;
static g_attrchanged_t g_dev_attrchanged;
static struct g_class g_dev_class = {
.name = "DEV",
.version = G_VERSION,
.init = g_dev_init,
.fini = g_dev_fini,
.taste = g_dev_taste,
.orphan = g_dev_orphan,
.attrchanged = g_dev_attrchanged
};
/*
* We target 262144 (8 x 32768) sectors by default as this significantly
* increases the throughput on commonly used SSD's with a marginal
* increase in non-interruptible request latency.
*/
static uint64_t g_dev_del_max_sectors = 262144;
SYSCTL_DECL(_kern_geom);
SYSCTL_NODE(_kern_geom, OID_AUTO, dev, CTLFLAG_RW, 0, "GEOM_DEV stuff");
SYSCTL_QUAD(_kern_geom_dev, OID_AUTO, delete_max_sectors, CTLFLAG_RW,
&g_dev_del_max_sectors, 0, "Maximum number of sectors in a single "
"delete request sent to the provider. Larger requests are chunked "
"so they can be interrupted. (0 = disable chunking)");
static char *dumpdev = NULL;
static void
g_dev_init(struct g_class *mp)
{
dumpdev = kern_getenv("dumpdev");
}
static void
g_dev_fini(struct g_class *mp)
{
freeenv(dumpdev);
dumpdev = NULL;
}
static int
g_dev_setdumpdev(struct cdev *dev, struct thread *td)
{
struct g_kerneldump kd;
struct g_consumer *cp;
int error, len;
if (dev == NULL)
return (set_dumper(NULL, NULL, td));
cp = dev->si_drv2;
len = sizeof(kd);
kd.offset = 0;
kd.length = OFF_MAX;
error = g_io_getattr("GEOM::kerneldump", cp, &len, &kd);
if (error == 0) {
error = set_dumper(&kd.di, devtoname(dev), td);
if (error == 0)
dev->si_flags |= SI_DUMPDEV;
}
return (error);
}
static void
init_dumpdev(struct cdev *dev)
{
const char *devprefix = "/dev/", *devname;
size_t len;
if (dumpdev == NULL)
return;
len = strlen(devprefix);
devname = devtoname(dev);
if (strcmp(devname, dumpdev) != 0 &&
(strncmp(dumpdev, devprefix, len) != 0 ||
strcmp(devname, dumpdev + len) != 0))
return;
if (g_dev_setdumpdev(dev, curthread) == 0) {
freeenv(dumpdev);
dumpdev = NULL;
}
}
static void
g_dev_destroy(void *arg, int flags __unused)
{
struct g_consumer *cp;
struct g_geom *gp;
struct g_dev_softc *sc;
char buf[SPECNAMELEN + 6];
g_topology_assert();
cp = arg;
gp = cp->geom;
sc = cp->private;
g_trace(G_T_TOPOLOGY, "g_dev_destroy(%p(%s))", cp, gp->name);
snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
devctl_notify_f("GEOM", "DEV", "DESTROY", buf, M_WAITOK);
if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
g_access(cp, -cp->acr, -cp->acw, -cp->ace);
g_detach(cp);
g_destroy_consumer(cp);
g_destroy_geom(gp);
mtx_destroy(&sc->sc_mtx);
g_free(sc);
}
void
g_dev_print(void)
{
struct g_geom *gp;
char const *p = "";
LIST_FOREACH(gp, &g_dev_class.geom, geom) {
printf("%s%s", p, gp->name);
p = " ";
}
printf("\n");
}
static void
g_dev_attrchanged(struct g_consumer *cp, const char *attr)
{
struct g_dev_softc *sc;
struct cdev *dev;
char buf[SPECNAMELEN + 6];
sc = cp->private;
if (strcmp(attr, "GEOM::media") == 0) {
dev = sc->sc_dev;
snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
devctl_notify_f("DEVFS", "CDEV", "MEDIACHANGE", buf, M_WAITOK);
devctl_notify_f("GEOM", "DEV", "MEDIACHANGE", buf, M_WAITOK);
dev = sc->sc_alias;
if (dev != NULL) {
snprintf(buf, sizeof(buf), "cdev=%s", dev->si_name);
devctl_notify_f("DEVFS", "CDEV", "MEDIACHANGE", buf,
M_WAITOK);
devctl_notify_f("GEOM", "DEV", "MEDIACHANGE", buf,
M_WAITOK);
}
return;
}
if (strcmp(attr, "GEOM::physpath") != 0)
return;
if (g_access(cp, 1, 0, 0) == 0) {
char *physpath;
int error, physpath_len;
physpath_len = MAXPATHLEN;
physpath = g_malloc(physpath_len, M_WAITOK|M_ZERO);
error =
g_io_getattr("GEOM::physpath", cp, &physpath_len, physpath);
g_access(cp, -1, 0, 0);
if (error == 0 && strlen(physpath) != 0) {
struct cdev *old_alias_dev;
struct cdev **alias_devp;
dev = sc->sc_dev;
old_alias_dev = sc->sc_alias;
alias_devp = (struct cdev **)&sc->sc_alias;
make_dev_physpath_alias(MAKEDEV_WAITOK, alias_devp,
dev, old_alias_dev, physpath);
} else if (sc->sc_alias) {
destroy_dev((struct cdev *)sc->sc_alias);
sc->sc_alias = NULL;
}
g_free(physpath);
}
}
struct g_provider *
g_dev_getprovider(struct cdev *dev)
{
struct g_consumer *cp;
g_topology_assert();
if (dev == NULL)
return (NULL);
if (dev->si_devsw != &g_dev_cdevsw)
return (NULL);
cp = dev->si_drv2;
return (cp->provider);
}
static struct g_geom *
g_dev_taste(struct g_class *mp, struct g_provider *pp, int insist __unused)
{
struct g_geom *gp;
struct g_consumer *cp;
struct g_dev_softc *sc;
int error, len;
struct cdev *dev, *adev;
char buf[SPECNAMELEN + 6], *val;
g_trace(G_T_TOPOLOGY, "dev_taste(%s,%s)", mp->name, pp->name);
g_topology_assert();
gp = g_new_geomf(mp, "%s", pp->name);
sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO);
mtx_init(&sc->sc_mtx, "g_dev", NULL, MTX_DEF);
cp = g_new_consumer(gp);
cp->private = sc;
cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
error = g_attach(cp, pp);
KASSERT(error == 0,
("g_dev_taste(%s) failed to g_attach, err=%d", pp->name, error));
error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &dev,
&g_dev_cdevsw, NULL, UID_ROOT, GID_OPERATOR, 0640, "%s", gp->name);
if (error != 0) {
printf("%s: make_dev_p() failed (gp->name=%s, error=%d)\n",
__func__, gp->name, error);
g_detach(cp);
g_destroy_consumer(cp);
g_destroy_geom(gp);
mtx_destroy(&sc->sc_mtx);
g_free(sc);
return (NULL);
}
dev->si_flags |= SI_UNMAPPED;
sc->sc_dev = dev;
/* Search for device alias name and create it if found. */
adev = NULL;
for (len = MIN(strlen(gp->name), sizeof(buf) - 15); len > 0; len--) {
snprintf(buf, sizeof(buf), "kern.devalias.%s", gp->name);
buf[14 + len] = 0;
val = kern_getenv(buf);
if (val != NULL) {
snprintf(buf, sizeof(buf), "%s%s",
val, gp->name + len);
freeenv(val);
if ((make_dev_alias_p(MAKEDEV_CHECKNAME|MAKEDEV_WAITOK,
&adev, dev, "%s", buf)) != 0)
printf("Warning: unable to create device "
"alias %s\n", buf);
break;
}
}
dev->si_iosize_max = MAXPHYS;
dev->si_drv2 = cp;
init_dumpdev(dev);
if (adev != NULL) {
adev->si_iosize_max = MAXPHYS;
adev->si_drv2 = cp;
adev->si_flags |= SI_UNMAPPED;
init_dumpdev(adev);
}
g_dev_attrchanged(cp, "GEOM::physpath");
snprintf(buf, sizeof(buf), "cdev=%s", gp->name);
devctl_notify_f("GEOM", "DEV", "CREATE", buf, M_WAITOK);
return (gp);
}
static int
g_dev_open(struct cdev *dev, int flags, int fmt, struct thread *td)
{
struct g_consumer *cp;
struct g_dev_softc *sc;
int error, r, w, e;
cp = dev->si_drv2;
if (cp == NULL)
return (ENXIO); /* g_dev_taste() not done yet */
g_trace(G_T_ACCESS, "g_dev_open(%s, %d, %d, %p)",
cp->geom->name, flags, fmt, td);
r = flags & FREAD ? 1 : 0;
w = flags & FWRITE ? 1 : 0;
#ifdef notyet
e = flags & O_EXCL ? 1 : 0;
#else
e = 0;
#endif
/*
* This happens on attempt to open a device node with O_EXEC.
*/
if (r + w + e == 0)
return (EINVAL);
if (w) {
/*
* When running in very secure mode, do not allow
* opens for writing of any disks.
*/
error = securelevel_ge(td->td_ucred, 2);
if (error)
return (error);
}
g_topology_lock();
error = g_access(cp, r, w, e);
g_topology_unlock();
if (error == 0) {
sc = cp->private;
mtx_lock(&sc->sc_mtx);
if (sc->sc_open == 0 && sc->sc_active != 0)
wakeup(&sc->sc_active);
sc->sc_open += r + w + e;
mtx_unlock(&sc->sc_mtx);
}
return (error);
}
static int
g_dev_close(struct cdev *dev, int flags, int fmt, struct thread *td)
{
struct g_consumer *cp;
struct g_dev_softc *sc;
int error, r, w, e;
cp = dev->si_drv2;
if (cp == NULL)
return (ENXIO);
g_trace(G_T_ACCESS, "g_dev_close(%s, %d, %d, %p)",
cp->geom->name, flags, fmt, td);
r = flags & FREAD ? -1 : 0;
w = flags & FWRITE ? -1 : 0;
#ifdef notyet
e = flags & O_EXCL ? -1 : 0;
#else
e = 0;
#endif
/*
* The vgonel(9) - caused by eg. forced unmount of devfs - calls
* VOP_CLOSE(9) on devfs vnode without any FREAD or FWRITE flags,
* which would result in zero deltas, which in turn would cause
* panic in g_access(9).
*
* Note that we cannot zero the counters (ie. do "r = cp->acr"
* etc) instead, because the consumer might be opened in another
* devfs instance.
*/
if (r + w + e == 0)
return (EINVAL);
sc = cp->private;
mtx_lock(&sc->sc_mtx);
sc->sc_open += r + w + e;
while (sc->sc_open == 0 && sc->sc_active != 0)
msleep(&sc->sc_active, &sc->sc_mtx, 0, "PRIBIO", 0);
mtx_unlock(&sc->sc_mtx);
g_topology_lock();
error = g_access(cp, r, w, e);
g_topology_unlock();
return (error);
}
/*
* XXX: Until we have unmessed the ioctl situation, there is a race against
* XXX: a concurrent orphanization. We cannot close it by holding topology
* XXX: since that would prevent us from doing our job, and stalling events
* XXX: will break (actually: stall) the BSD disklabel hacks.
*/
static int
g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
{
struct g_consumer *cp;
struct g_provider *pp;
off_t offset, length, chunk;
int i, error;
cp = dev->si_drv2;
pp = cp->provider;
error = 0;
KASSERT(cp->acr || cp->acw,
("Consumer with zero access count in g_dev_ioctl"));
i = IOCPARM_LEN(cmd);
switch (cmd) {
case DIOCGSECTORSIZE:
*(u_int *)data = cp->provider->sectorsize;
if (*(u_int *)data == 0)
error = ENOENT;
break;
case DIOCGMEDIASIZE:
*(off_t *)data = cp->provider->mediasize;
if (*(off_t *)data == 0)
error = ENOENT;
break;
case DIOCGFWSECTORS:
error = g_io_getattr("GEOM::fwsectors", cp, &i, data);
if (error == 0 && *(u_int *)data == 0)
error = ENOENT;
break;
case DIOCGFWHEADS:
error = g_io_getattr("GEOM::fwheads", cp, &i, data);
if (error == 0 && *(u_int *)data == 0)
error = ENOENT;
break;
case DIOCGFRONTSTUFF:
error = g_io_getattr("GEOM::frontstuff", cp, &i, data);
break;
case DIOCSKERNELDUMP:
if (*(u_int *)data == 0)
error = g_dev_setdumpdev(NULL, td);
else
error = g_dev_setdumpdev(dev, td);
break;
case DIOCGFLUSH:
error = g_io_flush(cp);
break;
case DIOCGDELETE:
offset = ((off_t *)data)[0];
length = ((off_t *)data)[1];
if ((offset % cp->provider->sectorsize) != 0 ||
(length % cp->provider->sectorsize) != 0 || length <= 0) {
printf("%s: offset=%jd length=%jd\n", __func__, offset,
length);
error = EINVAL;
break;
}
while (length > 0) {
chunk = length;
if (g_dev_del_max_sectors != 0 && chunk >
g_dev_del_max_sectors * cp->provider->sectorsize) {
chunk = g_dev_del_max_sectors *
cp->provider->sectorsize;
}
error = g_delete_data(cp, offset, chunk);
length -= chunk;
offset += chunk;
if (error)
break;
/*
* Since the request size can be large, the service
* time can be is likewise. We make this ioctl
* interruptible by checking for signals for each bio.
*/
if (SIGPENDING(td))
break;
}
break;
case DIOCGIDENT:
error = g_io_getattr("GEOM::ident", cp, &i, data);
break;
case DIOCGPROVIDERNAME:
if (pp == NULL)
return (ENOENT);
strlcpy(data, pp->name, i);
break;
case DIOCGSTRIPESIZE:
*(off_t *)data = cp->provider->stripesize;
break;
case DIOCGSTRIPEOFFSET:
*(off_t *)data = cp->provider->stripeoffset;
break;
case DIOCGPHYSPATH:
error = g_io_getattr("GEOM::physpath", cp, &i, data);
if (error == 0 && *(char *)data == '\0')
error = ENOENT;
break;
case DIOCGATTR: {
struct diocgattr_arg *arg = (struct diocgattr_arg *)data;
if (arg->len > sizeof(arg->value)) {
error = EINVAL;
break;
}
error = g_io_getattr(arg->name, cp, &arg->len, &arg->value);
break;
}
default:
if (cp->provider->geom->ioctl != NULL) {
error = cp->provider->geom->ioctl(cp->provider, cmd, data, fflag, td);
} else {
error = ENOIOCTL;
}
}
return (error);
}
static void
g_dev_done(struct bio *bp2)
{
struct g_consumer *cp;
struct g_dev_softc *sc;
struct bio *bp;
int destroy;
cp = bp2->bio_from;
sc = cp->private;
bp = bp2->bio_parent;
bp->bio_error = bp2->bio_error;
bp->bio_completed = bp2->bio_completed;
bp->bio_resid = bp->bio_length - bp2->bio_completed;
if (bp2->bio_error != 0) {
g_trace(G_T_BIO, "g_dev_done(%p) had error %d",
bp2, bp2->bio_error);
bp->bio_flags |= BIO_ERROR;
} else {
g_trace(G_T_BIO, "g_dev_done(%p/%p) resid %ld completed %jd",
bp2, bp, bp2->bio_resid, (intmax_t)bp2->bio_completed);
}
g_destroy_bio(bp2);
destroy = 0;
mtx_lock(&sc->sc_mtx);
if ((--sc->sc_active) == 0) {
if (sc->sc_open == 0)
wakeup(&sc->sc_active);
if (sc->sc_dev == NULL)
destroy = 1;
}
mtx_unlock(&sc->sc_mtx);
if (destroy)
g_post_event(g_dev_destroy, cp, M_NOWAIT, NULL);
biodone(bp);
}
static void
g_dev_strategy(struct bio *bp)
{
struct g_consumer *cp;
struct bio *bp2;
struct cdev *dev;
struct g_dev_softc *sc;
KASSERT(bp->bio_cmd == BIO_READ ||
bp->bio_cmd == BIO_WRITE ||
bp->bio_cmd == BIO_DELETE ||
bp->bio_cmd == BIO_FLUSH,
("Wrong bio_cmd bio=%p cmd=%d", bp, bp->bio_cmd));
dev = bp->bio_dev;
cp = dev->si_drv2;
sc = cp->private;
KASSERT(cp->acr || cp->acw,
("Consumer with zero access count in g_dev_strategy"));
#ifdef INVARIANTS
if ((bp->bio_offset % cp->provider->sectorsize) != 0 ||
(bp->bio_bcount % cp->provider->sectorsize) != 0) {
bp->bio_resid = bp->bio_bcount;
biofinish(bp, NULL, EINVAL);
return;
}
#endif
mtx_lock(&sc->sc_mtx);
KASSERT(sc->sc_open > 0, ("Closed device in g_dev_strategy"));
sc->sc_active++;
mtx_unlock(&sc->sc_mtx);
for (;;) {
/*
* XXX: This is not an ideal solution, but I belive it to
* XXX: deadlock safe, all things considered.
*/
bp2 = g_clone_bio(bp);
if (bp2 != NULL)
break;
pause("gdstrat", hz / 10);
}
KASSERT(bp2 != NULL, ("XXX: ENOMEM in a bad place"));
bp2->bio_done = g_dev_done;
g_trace(G_T_BIO,
"g_dev_strategy(%p/%p) offset %jd length %jd data %p cmd %d",
bp, bp2, (intmax_t)bp->bio_offset, (intmax_t)bp2->bio_length,
bp2->bio_data, bp2->bio_cmd);
g_io_request(bp2, cp);
KASSERT(cp->acr || cp->acw,
("g_dev_strategy raced with g_dev_close and lost"));
}
/*
* g_dev_callback()
*
* Called by devfs when asynchronous device destruction is completed.
* - Mark that we have no attached device any more.
* - If there are no outstanding requests, schedule geom destruction.
* Otherwise destruction will be scheduled later by g_dev_done().
*/
static void
g_dev_callback(void *arg)
{
struct g_consumer *cp;
struct g_dev_softc *sc;
int destroy;
cp = arg;
sc = cp->private;
g_trace(G_T_TOPOLOGY, "g_dev_callback(%p(%s))", cp, cp->geom->name);
mtx_lock(&sc->sc_mtx);
sc->sc_dev = NULL;
sc->sc_alias = NULL;
destroy = (sc->sc_active == 0);
mtx_unlock(&sc->sc_mtx);
if (destroy)
g_post_event(g_dev_destroy, cp, M_WAITOK, NULL);
}
/*
* g_dev_orphan()
*
* Called from below when the provider orphaned us.
* - Clear any dump settings.
* - Request asynchronous device destruction to prevent any more requests
* from coming in. The provider is already marked with an error, so
* anything which comes in in the interrim will be returned immediately.
*/
static void
g_dev_orphan(struct g_consumer *cp)
{
struct cdev *dev;
struct g_dev_softc *sc;
g_topology_assert();
sc = cp->private;
dev = sc->sc_dev;
g_trace(G_T_TOPOLOGY, "g_dev_orphan(%p(%s))", cp, cp->geom->name);
/* Reset any dump-area set on this device */
if (dev->si_flags & SI_DUMPDEV)
(void)set_dumper(NULL, NULL, curthread);
/* Destroy the struct cdev *so we get no more requests */
destroy_dev_sched_cb(dev, g_dev_callback, cp);
}
DECLARE_GEOM_CLASS(g_dev_class, g_dev);