vdev_disk.c revision f4a724507725f215972bd6c8cdaaa33b0803e58d
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <sys/zfs_context.h>
#include <sys/spa.h>
#include <sys/refcount.h>
#include <sys/vdev_disk.h>
#include <sys/vdev_impl.h>
#include <sys/fs/zfs.h>
#include <sys/zio.h>
#include <sys/sunldi.h>
#include <sys/fm/fs/zfs.h>
/*
* Virtual device vector for disks.
*/
extern ldi_ident_t zfs_li;
typedef struct vdev_disk_buf {
buf_t vdb_buf;
zio_t *vdb_io;
} vdev_disk_buf_t;
static int
vdev_disk_open(vdev_t *vd, uint64_t *psize, uint64_t *ashift)
{
vdev_disk_t *dvd;
struct dk_minfo dkm;
int error;
dev_t dev;
int otyp;
/*
* We must have a pathname, and it must be absolute.
*/
if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') {
vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
return (EINVAL);
}
dvd = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_disk_t), KM_SLEEP);
/*
* When opening a disk device, we want to preserve the user's original
* intent. We always want to open the device by the path the user gave
* us, even if it is one of multiple paths to the save device. But we
* also want to be able to survive disks being removed/recabled.
* Therefore the sequence of opening devices is:
*
* 1. Try opening the device by path. For legacy pools without the
* 'whole_disk' property, attempt to fix the path by appending 's0'.
*
* 2. If the devid of the device matches the stored value, return
* success.
*
* 3. Otherwise, the device may have moved. Try opening the device
* by the devid instead.
*
* If the vdev is part of the root pool, we avoid opening it by path.
* We do this because there is no /dev path available early in boot,
* and if we try to open the device by path at a later point, we can
* deadlock when devfsadm attempts to open the underlying backing store
* file.
*/
if (vd->vdev_devid != NULL) {
if (ddi_devid_str_decode(vd->vdev_devid, &dvd->vd_devid,
&dvd->vd_minor) != 0) {
vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
return (EINVAL);
}
}
error = EINVAL; /* presume failure */
if (vd->vdev_path != NULL && !spa_is_root(vd->vdev_spa)) {
ddi_devid_t devid;
if (vd->vdev_wholedisk == -1ULL) {
size_t len = strlen(vd->vdev_path) + 3;
char *buf = kmem_alloc(len, KM_SLEEP);
ldi_handle_t lh;
(void) snprintf(buf, len, "%ss0", vd->vdev_path);
if (ldi_open_by_name(buf, spa_mode, kcred,
&lh, zfs_li) == 0) {
spa_strfree(vd->vdev_path);
vd->vdev_path = buf;
vd->vdev_wholedisk = 1ULL;
(void) ldi_close(lh, spa_mode, kcred);
} else {
kmem_free(buf, len);
}
}
error = ldi_open_by_name(vd->vdev_path, spa_mode, kcred,
&dvd->vd_lh, zfs_li);
/*
* Compare the devid to the stored value.
*/
if (error == 0 && vd->vdev_devid != NULL &&
ldi_get_devid(dvd->vd_lh, &devid) == 0) {
if (ddi_devid_compare(devid, dvd->vd_devid) != 0) {
error = EINVAL;
(void) ldi_close(dvd->vd_lh, spa_mode, kcred);
dvd->vd_lh = NULL;
}
ddi_devid_free(devid);
}
/*
* If we succeeded in opening the device, but 'vdev_wholedisk'
* is not yet set, then this must be a slice.
*/
if (error == 0 && vd->vdev_wholedisk == -1ULL)
vd->vdev_wholedisk = 0;
}
/*
* If we were unable to open by path, or the devid check fails, open by
* devid instead.
*/
if (error != 0 && vd->vdev_devid != NULL)
error = ldi_open_by_devid(dvd->vd_devid, dvd->vd_minor,
spa_mode, kcred, &dvd->vd_lh, zfs_li);
/*
* If all else fails, then try opening by physical path (if available)
* or the logical path (if we failed due to the devid check). While not
* as reliable as the devid, this will give us something, and the higher
* level vdev validation will prevent us from opening the wrong device.
*/
if (error) {
if (vd->vdev_physpath != NULL &&
(dev = ddi_pathname_to_dev_t(vd->vdev_physpath)) != ENODEV)
error = ldi_open_by_dev(&dev, OTYP_BLK, spa_mode,
kcred, &dvd->vd_lh, zfs_li);
/*
* Note that we don't support the legacy auto-wholedisk support
* as above. This hasn't been used in a very long time and we
* don't need to propagate its oddities to this edge condition.
*/
if (error && vd->vdev_path != NULL &&
!spa_is_root(vd->vdev_spa))
error = ldi_open_by_name(vd->vdev_path, spa_mode, kcred,
&dvd->vd_lh, zfs_li);
}
if (error) {
vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
return (error);
}
/*
* Once a device is opened, verify that the physical device path (if
* available) is up to date.
*/
if (ldi_get_dev(dvd->vd_lh, &dev) == 0 &&
ldi_get_otyp(dvd->vd_lh, &otyp) == 0) {
char *physpath, *minorname;
physpath = kmem_alloc(MAXPATHLEN, KM_SLEEP);
minorname = NULL;
if (ddi_dev_pathname(dev, otyp, physpath) == 0 &&
ldi_get_minor_name(dvd->vd_lh, &minorname) == 0 &&
(vd->vdev_physpath == NULL ||
strcmp(vd->vdev_physpath, physpath) != 0)) {
if (vd->vdev_physpath)
spa_strfree(vd->vdev_physpath);
(void) strlcat(physpath, ":", MAXPATHLEN);
(void) strlcat(physpath, minorname, MAXPATHLEN);
vd->vdev_physpath = spa_strdup(physpath);
}
if (minorname)
kmem_free(minorname, strlen(minorname) + 1);
kmem_free(physpath, MAXPATHLEN);
}
/*
* Determine the actual size of the device.
*/
if (ldi_get_size(dvd->vd_lh, psize) != 0) {
vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
return (EINVAL);
}
/*
* If we own the whole disk, try to enable disk write caching.
* We ignore errors because it's OK if we can't do it.
*/
if (vd->vdev_wholedisk == 1) {
int wce = 1;
(void) ldi_ioctl(dvd->vd_lh, DKIOCSETWCE, (intptr_t)&wce,
FKIOCTL, kcred, NULL);
}
/*
* Determine the device's minimum transfer size.
* If the ioctl isn't supported, assume DEV_BSIZE.
*/
if (ldi_ioctl(dvd->vd_lh, DKIOCGMEDIAINFO, (intptr_t)&dkm,
FKIOCTL, kcred, NULL) != 0)
dkm.dki_lbsize = DEV_BSIZE;
*ashift = highbit(MAX(dkm.dki_lbsize, SPA_MINBLOCKSIZE)) - 1;
/*
* Clear the nowritecache bit, so that on a vdev_reopen() we will
* try again.
*/
vd->vdev_nowritecache = B_FALSE;
return (0);
}
static void
vdev_disk_close(vdev_t *vd)
{
vdev_disk_t *dvd = vd->vdev_tsd;
if (dvd == NULL)
return;
if (dvd->vd_minor != NULL)
ddi_devid_str_free(dvd->vd_minor);
if (dvd->vd_devid != NULL)
ddi_devid_free(dvd->vd_devid);
if (dvd->vd_lh != NULL)
(void) ldi_close(dvd->vd_lh, spa_mode, kcred);
kmem_free(dvd, sizeof (vdev_disk_t));
vd->vdev_tsd = NULL;
}
int
vdev_disk_physio(ldi_handle_t vd_lh, caddr_t data, size_t size,
uint64_t offset, int flags)
{
buf_t *bp;
int error = 0;
if (vd_lh == NULL)
return (EINVAL);
ASSERT(flags & B_READ || flags & B_WRITE);
bp = getrbuf(KM_SLEEP);
bp->b_flags = flags | B_BUSY | B_NOCACHE | B_FAILFAST;
bp->b_bcount = size;
bp->b_un.b_addr = (void *)data;
bp->b_lblkno = lbtodb(offset);
bp->b_bufsize = size;
error = ldi_strategy(vd_lh, bp);
ASSERT(error == 0);
if ((error = biowait(bp)) == 0 && bp->b_resid != 0)
error = EIO;
freerbuf(bp);
return (error);
}
static void
vdev_disk_io_intr(buf_t *bp)
{
vdev_disk_buf_t *vdb = (vdev_disk_buf_t *)bp;
zio_t *zio = vdb->vdb_io;
/*
* The rest of the zio stack only deals with EIO, ECKSUM, and ENXIO.
* Rather than teach the rest of the stack about other error
* possibilities (EFAULT, etc), we normalize the error value here.
*/
zio->io_error = (geterror(bp) != 0 ? EIO : 0);
if (zio->io_error == 0 && bp->b_resid != 0)
zio->io_error = EIO;
kmem_free(vdb, sizeof (vdev_disk_buf_t));
zio_interrupt(zio);
}
static void
vdev_disk_ioctl_free(zio_t *zio)
{
kmem_free(zio->io_vsd, sizeof (struct dk_callback));
}
static void
vdev_disk_ioctl_done(void *zio_arg, int error)
{
zio_t *zio = zio_arg;
zio->io_error = error;
zio_interrupt(zio);
}
static int
vdev_disk_io_start(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
vdev_disk_t *dvd = vd->vdev_tsd;
vdev_disk_buf_t *vdb;
struct dk_callback *dkc;
buf_t *bp;
int error;
if (zio->io_type == ZIO_TYPE_IOCTL) {
/* XXPOLICY */
if (!vdev_readable(vd)) {
zio->io_error = ENXIO;
return (ZIO_PIPELINE_CONTINUE);
}
switch (zio->io_cmd) {
case DKIOCFLUSHWRITECACHE:
if (zfs_nocacheflush)
break;
if (vd->vdev_nowritecache) {
zio->io_error = ENOTSUP;
break;
}
zio->io_vsd = dkc = kmem_alloc(sizeof (*dkc), KM_SLEEP);
zio->io_vsd_free = vdev_disk_ioctl_free;
dkc->dkc_callback = vdev_disk_ioctl_done;
dkc->dkc_flag = FLUSH_VOLATILE;
dkc->dkc_cookie = zio;
error = ldi_ioctl(dvd->vd_lh, zio->io_cmd,
(uintptr_t)dkc, FKIOCTL, kcred, NULL);
if (error == 0) {
/*
* The ioctl will be done asychronously,
* and will call vdev_disk_ioctl_done()
* upon completion.
*/
return (ZIO_PIPELINE_STOP);
}
if (error == ENOTSUP || error == ENOTTY) {
/*
* If we get ENOTSUP or ENOTTY, we know that
* no future attempts will ever succeed.
* In this case we set a persistent bit so
* that we don't bother with the ioctl in the
* future.
*/
vd->vdev_nowritecache = B_TRUE;
}
zio->io_error = error;
break;
default:
zio->io_error = ENOTSUP;
}
return (ZIO_PIPELINE_CONTINUE);
}
vdb = kmem_alloc(sizeof (vdev_disk_buf_t), KM_SLEEP);
vdb->vdb_io = zio;
bp = &vdb->vdb_buf;
bioinit(bp);
bp->b_flags = B_BUSY | B_NOCACHE |
(zio->io_type == ZIO_TYPE_READ ? B_READ : B_WRITE) |
((zio->io_flags & ZIO_FLAG_IO_RETRY) ? 0 : B_FAILFAST);
bp->b_bcount = zio->io_size;
bp->b_un.b_addr = zio->io_data;
bp->b_lblkno = lbtodb(zio->io_offset);
bp->b_bufsize = zio->io_size;
bp->b_iodone = (int (*)())vdev_disk_io_intr;
/* ldi_strategy() will return non-zero only on programming errors */
VERIFY(ldi_strategy(dvd->vd_lh, bp) == 0);
return (ZIO_PIPELINE_STOP);
}
static void
vdev_disk_io_done(zio_t *zio)
{
vdev_t *vd = zio->io_vd;
/*
* If the device returned EIO, then attempt a DKIOCSTATE ioctl to see if
* the device has been removed. If this is the case, then we trigger an
* asynchronous removal of the device. Otherwise, probe the device and
* make sure it's still accessible.
*/
if (zio->io_error == EIO) {
vdev_disk_t *dvd = vd->vdev_tsd;
int state = DKIO_NONE;
if (ldi_ioctl(dvd->vd_lh, DKIOCSTATE, (intptr_t)&state,
FKIOCTL, kcred, NULL) == 0 && state != DKIO_INSERTED) {
vd->vdev_remove_wanted = B_TRUE;
spa_async_request(zio->io_spa, SPA_ASYNC_REMOVE);
}
}
}
vdev_ops_t vdev_disk_ops = {
vdev_disk_open,
vdev_disk_close,
vdev_default_asize,
vdev_disk_io_start,
vdev_disk_io_done,
NULL,
VDEV_TYPE_DISK, /* name of this vdev type */
B_TRUE /* leaf vdev */
};
/*
* Given the root disk device devid or pathname, read the label from
* the device, and construct a configuration nvlist.
*/
int
vdev_disk_read_rootlabel(char *devpath, char *devid, nvlist_t **config)
{
ldi_handle_t vd_lh;
vdev_label_t *label;
uint64_t s, size;
int l;
ddi_devid_t tmpdevid;
int error = -1;
char *minor_name;
/*
* Read the device label and build the nvlist.
*/
if (devid != NULL && ddi_devid_str_decode(devid, &tmpdevid,
&minor_name) == 0) {
error = ldi_open_by_devid(tmpdevid, minor_name,
spa_mode, kcred, &vd_lh, zfs_li);
ddi_devid_free(tmpdevid);
ddi_devid_str_free(minor_name);
}
if (error && (error = ldi_open_by_name(devpath, FREAD, kcred, &vd_lh,
zfs_li)))
return (error);
if (ldi_get_size(vd_lh, &s)) {
(void) ldi_close(vd_lh, FREAD, kcred);
return (EIO);
}
size = P2ALIGN_TYPED(s, sizeof (vdev_label_t), uint64_t);
label = kmem_alloc(sizeof (vdev_label_t), KM_SLEEP);
for (l = 0; l < VDEV_LABELS; l++) {
uint64_t offset, state, txg = 0;
/* read vdev label */
offset = vdev_label_offset(size, l, 0);
if (vdev_disk_physio(vd_lh, (caddr_t)label,
VDEV_SKIP_SIZE + VDEV_BOOT_HEADER_SIZE +
VDEV_PHYS_SIZE, offset, B_READ) != 0)
continue;
if (nvlist_unpack(label->vl_vdev_phys.vp_nvlist,
sizeof (label->vl_vdev_phys.vp_nvlist), config, 0) != 0) {
*config = NULL;
continue;
}
if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE,
&state) != 0 || state >= POOL_STATE_DESTROYED) {
nvlist_free(*config);
*config = NULL;
continue;
}
if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
&txg) != 0 || txg == 0) {
nvlist_free(*config);
*config = NULL;
continue;
}
break;
}
kmem_free(label, sizeof (vdev_label_t));
(void) ldi_close(vd_lh, FREAD, kcred);
return (error);
}