libzfs_import.c revision 4c58d71403cebfaa40a572ff12b17668ebd56987
/*
* 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 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Pool import support functions.
*
* To import a pool, we rely on reading the configuration information from the
* ZFS label of each device. If we successfully read the label, then we
* organize the configuration information in the following hierarchy:
*
* pool guid -> toplevel vdev guid -> label txg
*
* Duplicate entries matching this same tuple will be discarded. Once we have
* examined every device, we pick the best label txg config for each toplevel
* vdev. We then arrange these toplevel vdevs into a complete pool config, and
* update any paths that have changed. Finally, we attempt to import the pool
* using our derived config, and record the results.
*/
#include <devid.h>
#include <dirent.h>
#include <errno.h>
#include <libintl.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/vdev_impl.h>
#include "libzfs.h"
#include "libzfs_impl.h"
/*
* Intermediate structures used to gather configuration information.
*/
typedef struct config_entry {
uint64_t ce_txg;
nvlist_t *ce_config;
struct config_entry *ce_next;
} config_entry_t;
typedef struct vdev_entry {
uint64_t ve_guid;
config_entry_t *ve_configs;
struct vdev_entry *ve_next;
} vdev_entry_t;
typedef struct pool_entry {
uint64_t pe_guid;
vdev_entry_t *pe_vdevs;
struct pool_entry *pe_next;
} pool_entry_t;
typedef struct name_entry {
const char *ne_name;
uint64_t ne_guid;
struct name_entry *ne_next;
} name_entry_t;
typedef struct pool_list {
pool_entry_t *pools;
name_entry_t *names;
} pool_list_t;
static char *
get_devid(const char *path)
{
int fd;
ddi_devid_t devid;
char *minor, *ret;
if ((fd = open(path, O_RDONLY)) < 0)
return (NULL);
minor = NULL;
ret = NULL;
if (devid_get(fd, &devid) == 0) {
if (devid_get_minor_name(fd, &minor) == 0)
ret = devid_str_encode(devid, minor);
if (minor != NULL)
devid_str_free(minor);
devid_free(devid);
}
(void) close(fd);
return (ret);
}
/*
* Go through and fix up any path and/or devid information for the given vdev
* configuration.
*/
static void
fix_paths(nvlist_t *nv, name_entry_t *names)
{
nvlist_t **child;
uint_t c, children;
uint64_t guid;
name_entry_t *ne, *best;
char *path, *devid;
int matched;
if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
&child, &children) == 0) {
for (c = 0; c < children; c++)
fix_paths(child[c], names);
return;
}
/*
* This is a leaf (file or disk) vdev. In either case, go through
* the name list and see if we find a matching guid. If so, replace
* the path and see if we can calculate a new devid.
*
* There may be multiple names associated with a particular guid, in
* which case we have overlapping slices or multiple paths to the same
* disk. If this is the case, then we want to pick the path that is
* the most similar to the original, where "most similar" is the number
* of matching characters starting from the end of the path. This will
* preserve slice numbers even if the disks have been reorganized, and
* will also catch preferred disk names if multiple paths exist.
*/
verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &guid) == 0);
if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) != 0)
path = NULL;
matched = 0;
best = NULL;
for (ne = names; ne != NULL; ne = ne->ne_next) {
if (ne->ne_guid == guid) {
const char *src, *dst;
int count;
if (path == NULL) {
best = ne;
break;
}
src = ne->ne_name + strlen(ne->ne_name) - 1;
dst = path + strlen(path) - 1;
for (count = 0; src >= ne->ne_name && dst >= path;
src--, dst--, count++)
if (*src != *dst)
break;
/*
* At this point, 'count' is the number of characters
* matched from the end.
*/
if (count > matched || best == NULL) {
best = ne;
matched = count;
}
}
}
if (best == NULL)
return;
verify(nvlist_add_string(nv, ZPOOL_CONFIG_PATH, best->ne_name) == 0);
if ((devid = get_devid(best->ne_name)) == NULL) {
(void) nvlist_remove_all(nv, ZPOOL_CONFIG_DEVID);
} else {
verify(nvlist_add_string(nv, ZPOOL_CONFIG_DEVID, devid) == 0);
devid_str_free(devid);
}
}
/*
* Add the given configuration to the list of known devices.
*/
static void
add_config(pool_list_t *pl, const char *path, nvlist_t *config)
{
uint64_t pool_guid, vdev_guid, top_guid, txg;
pool_entry_t *pe;
vdev_entry_t *ve;
config_entry_t *ce;
name_entry_t *ne;
/*
* If we have a valid config but cannot read any of these fields, then
* it means we have a half-initialized label. In vdev_label_init()
* we write a label with txg == 0 so that we can identify the device
* in case the user refers to the same disk later on. If we fail to
* create the pool, we'll be left with a label in this state
* which should not be considered part of a valid pool.
*/
if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
&pool_guid) != 0 ||
nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
&vdev_guid) != 0 ||
nvlist_lookup_uint64(config, ZPOOL_CONFIG_TOP_GUID,
&top_guid) != 0 ||
nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
&txg) != 0 || txg == 0) {
nvlist_free(config);
return;
}
/*
* First, see if we know about this pool. If not, then add it to the
* list of known pools.
*/
for (pe = pl->pools; pe != NULL; pe = pe->pe_next) {
if (pe->pe_guid == pool_guid)
break;
}
if (pe == NULL) {
pe = zfs_malloc(sizeof (pool_entry_t));
pe->pe_guid = pool_guid;
pe->pe_next = pl->pools;
pl->pools = pe;
}
/*
* Second, see if we know about this toplevel vdev. Add it if its
* missing.
*/
for (ve = pe->pe_vdevs; ve != NULL; ve = ve->ve_next) {
if (ve->ve_guid == top_guid)
break;
}
if (ve == NULL) {
ve = zfs_malloc(sizeof (vdev_entry_t));
ve->ve_guid = top_guid;
ve->ve_next = pe->pe_vdevs;
pe->pe_vdevs = ve;
}
/*
* Third, see if we have a config with a matching transaction group. If
* so, then we do nothing. Otherwise, add it to the list of known
* configs.
*/
for (ce = ve->ve_configs; ce != NULL; ce = ce->ce_next) {
if (ce->ce_txg == txg)
break;
}
if (ce == NULL) {
ce = zfs_malloc(sizeof (config_entry_t));
ce->ce_txg = txg;
ce->ce_config = config;
ce->ce_next = ve->ve_configs;
ve->ve_configs = ce;
} else {
nvlist_free(config);
}
/*
* At this point we've successfully added our config to the list of
* known configs. The last thing to do is add the vdev guid -> path
* mappings so that we can fix up the configuration as necessary before
* doing the import.
*/
ne = zfs_malloc(sizeof (name_entry_t));
ne->ne_name = zfs_strdup(path);
ne->ne_guid = vdev_guid;
ne->ne_next = pl->names;
pl->names = ne;
}
/*
* Convert our list of pools into the definitive set of configurations. We
* start by picking the best config for each toplevel vdev. Once that's done,
* we assemble the toplevel vdevs into a full config for the pool. We make a
* pass to fix up any incorrect paths, and then add it to the main list to
* return to the user.
*/
static nvlist_t *
get_configs(pool_list_t *pl)
{
pool_entry_t *pe, *penext;
vdev_entry_t *ve, *venext;
config_entry_t *ce, *cenext;
nvlist_t *ret, *config, *tmp, *nvtop, *nvroot;
int config_seen;
uint64_t best_txg;
char *name;
zfs_cmd_t zc = { 0 };
uint64_t guid;
char *packed;
size_t len;
int err;
verify(nvlist_alloc(&ret, 0, 0) == 0);
for (pe = pl->pools; pe != NULL; pe = penext) {
uint_t c;
uint_t children = 0;
uint64_t id;
nvlist_t **child = NULL;
penext = pe->pe_next;
verify(nvlist_alloc(&config, NV_UNIQUE_NAME, 0) == 0);
config_seen = FALSE;
/*
* Iterate over all toplevel vdevs. Grab the pool configuration
* from the first one we find, and then go through the rest and
* add them as necessary to the 'vdevs' member of the config.
*/
for (ve = pe->pe_vdevs; ve != NULL; ve = venext) {
venext = ve->ve_next;
/*
* Determine the best configuration for this vdev by
* selecting the config with the latest transaction
* group.
*/
best_txg = 0;
for (ce = ve->ve_configs; ce != NULL;
ce = ce->ce_next) {
if (ce->ce_txg > best_txg)
tmp = ce->ce_config;
}
if (!config_seen) {
/*
* Copy the relevant pieces of data to the pool
* configuration:
*
* pool guid
* name
* pool state
*/
uint64_t state;
verify(nvlist_lookup_uint64(tmp,
ZPOOL_CONFIG_POOL_GUID, &guid) == 0);
verify(nvlist_add_uint64(config,
ZPOOL_CONFIG_POOL_GUID, guid) == 0);
verify(nvlist_lookup_string(tmp,
ZPOOL_CONFIG_POOL_NAME, &name) == 0);
verify(nvlist_add_string(config,
ZPOOL_CONFIG_POOL_NAME, name) == 0);
verify(nvlist_lookup_uint64(tmp,
ZPOOL_CONFIG_POOL_STATE, &state) == 0);
verify(nvlist_add_uint64(config,
ZPOOL_CONFIG_POOL_STATE, state) == 0);
config_seen = TRUE;
}
/*
* Add this top-level vdev to the child array.
*/
verify(nvlist_lookup_nvlist(tmp,
ZPOOL_CONFIG_VDEV_TREE, &nvtop) == 0);
verify(nvlist_lookup_uint64(nvtop, ZPOOL_CONFIG_ID,
&id) == 0);
if (id >= children) {
nvlist_t **newchild;
newchild = zfs_malloc((id + 1) *
sizeof (nvlist_t *));
for (c = 0; c < children; c++)
newchild[c] = child[c];
free(child);
child = newchild;
children = id + 1;
}
verify(nvlist_dup(nvtop, &child[id], 0) == 0);
/*
* Go through and free all config information.
*/
for (ce = ve->ve_configs; ce != NULL; ce = cenext) {
cenext = ce->ce_next;
nvlist_free(ce->ce_config);
free(ce);
}
/*
* Free this vdev entry, since it has now been merged
* into the main config.
*/
free(ve);
}
verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
&guid) == 0);
/*
* Look for any missing top-level vdevs. If this is the case,
* create a faked up 'missing' vdev as a placeholder. We cannot
* simply compress the child array, because the kernel performs
* certain checks to make sure the vdev IDs match their location
* in the configuration.
*/
for (c = 0; c < children; c++)
if (child[c] == NULL) {
nvlist_t *missing;
verify(nvlist_alloc(&missing, NV_UNIQUE_NAME,
0) == 0);
verify(nvlist_add_string(missing,
ZPOOL_CONFIG_TYPE, VDEV_TYPE_MISSING) == 0);
verify(nvlist_add_uint64(missing,
ZPOOL_CONFIG_ID, c) == 0);
verify(nvlist_add_uint64(missing,
ZPOOL_CONFIG_GUID, 0ULL) == 0);
child[c] = missing;
}
/*
* Put all of this pool's top-level vdevs into a root vdev.
*/
verify(nvlist_alloc(&nvroot, NV_UNIQUE_NAME, 0) == 0);
verify(nvlist_add_string(nvroot, ZPOOL_CONFIG_TYPE,
VDEV_TYPE_ROOT) == 0);
verify(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_ID, 0ULL) == 0);
verify(nvlist_add_uint64(nvroot, ZPOOL_CONFIG_GUID, guid) == 0);
verify(nvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_CHILDREN,
child, children) == 0);
for (c = 0; c < children; c++)
nvlist_free(child[c]);
free(child);
/*
* Go through and fix up any paths and/or devids based on our
* known list of vdev GUID -> path mappings.
*/
fix_paths(nvroot, pl->names);
/*
* Add the root vdev to this pool's configuration.
*/
verify(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
nvroot) == 0);
nvlist_free(nvroot);
/*
* Free this pool entry.
*/
free(pe);
/*
* Determine if this pool is currently active, in which case we
* can't actually import it.
*/
verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
&name) == 0);
verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
&guid) == 0);
(void) strlcpy(zc.zc_name, name, sizeof (zc.zc_name));
if (zfs_ioctl(ZFS_IOC_POOL_GUID, &zc) == 0 &&
guid == zc.zc_guid) {
nvlist_free(config);
continue;
}
/*
* Try to do the import in order to get vdev state.
*/
if ((err = nvlist_size(config, &len, NV_ENCODE_NATIVE)) != 0)
zfs_baderror(err);
packed = zfs_malloc(len);
if ((err = nvlist_pack(config, &packed, &len,
NV_ENCODE_NATIVE, 0)) != 0)
zfs_baderror(err);
nvlist_free(config);
config = NULL;
zc.zc_config_src_size = len;
zc.zc_config_src = (uint64_t)(uintptr_t)packed;
zc.zc_config_dst_size = 2 * len;
zc.zc_config_dst = (uint64_t)(uintptr_t)
zfs_malloc(zc.zc_config_dst_size);
while ((err = zfs_ioctl(ZFS_IOC_POOL_TRYIMPORT,
&zc)) != 0 && errno == ENOMEM) {
free((void *)(uintptr_t)zc.zc_config_dst);
zc.zc_config_dst = (uint64_t)(uintptr_t)
zfs_malloc(zc.zc_config_dst_size);
}
free(packed);
if (err)
zfs_baderror(errno);
verify(nvlist_unpack((void *)(uintptr_t)zc.zc_config_dst,
zc.zc_config_dst_size, &config, 0) == 0);
set_pool_health(config);
/*
* Add this pool to the list of configs.
*/
verify(nvlist_add_nvlist(ret, name, config) == 0);
nvlist_free(config);
free((void *)(uintptr_t)zc.zc_config_dst);
}
return (ret);
}
/*
* Return the offset of the given label.
*/
static uint64_t
label_offset(size_t size, int l)
{
return (l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ?
0 : size - VDEV_LABELS * sizeof (vdev_label_t)));
}
/*
* Given a file descriptor, read the label information and return an nvlist
* describing the configuration, if there is one.
*/
nvlist_t *
zpool_read_label(int fd)
{
struct stat64 statbuf;
int l;
vdev_label_t *label;
nvlist_t *config;
uint64_t state, txg;
if (fstat64(fd, &statbuf) == -1)
return (NULL);
label = zfs_malloc(sizeof (vdev_label_t));
for (l = 0; l < VDEV_LABELS; l++) {
if (pread(fd, label, sizeof (vdev_label_t),
label_offset(statbuf.st_size, l)) != sizeof (vdev_label_t))
continue;
if (nvlist_unpack(label->vl_vdev_phys.vp_nvlist,
sizeof (label->vl_vdev_phys.vp_nvlist), &config, 0) != 0)
continue;
if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
&state) != 0 || state > POOL_STATE_DESTROYED) {
nvlist_free(config);
continue;
}
if (nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_TXG,
&txg) != 0 || txg == 0) {
nvlist_free(config);
continue;
}
free(label);
return (config);
}
free(label);
return (NULL);
}
/*
* Given a list of directories to search, find all pools stored on disk. This
* includes partial pools which are not available to import. If no args are
* given (argc is 0), then the default directory (/dev/dsk) is searched.
*/
nvlist_t *
zpool_find_import(int argc, char **argv)
{
int i;
DIR *dirp;
struct dirent64 *dp;
char path[MAXPATHLEN];
struct stat64 statbuf;
nvlist_t *ret, *config;
static char *default_dir = "/dev/dsk";
int fd;
pool_list_t pools = { 0 };
if (argc == 0) {
argc = 1;
argv = &default_dir;
}
/*
* Go through and read the label configuration information from every
* possible device, organizing the information according to pool GUID
* and toplevel GUID.
*/
for (i = 0; i < argc; i++) {
if (argv[i][0] != '/') {
zfs_error(dgettext(TEXT_DOMAIN,
"cannot open '%s': must be an absolute path"),
argv[i]);
return (NULL);
}
if ((dirp = opendir(argv[i])) == NULL) {
zfs_error(dgettext(TEXT_DOMAIN,
"cannot open '%s': %s"), argv[i],
strerror(errno));
return (NULL);
}
/*
* This is not MT-safe, but we have no MT consumers of libzfs
*/
while ((dp = readdir64(dirp)) != NULL) {
(void) snprintf(path, sizeof (path), "%s/%s",
argv[i], dp->d_name);
if (stat64(path, &statbuf) != 0)
continue;
/*
* Ignore directories (which includes "." and "..").
*/
if (S_ISDIR(statbuf.st_mode))
continue;
if ((fd = open64(path, O_RDONLY)) < 0)
continue;
config = zpool_read_label(fd);
(void) close(fd);
if (config != NULL)
add_config(&pools, path, config);
}
}
ret = get_configs(&pools);
return (ret);
}
int
find_guid(nvlist_t *nv, uint64_t guid)
{
uint64_t tmp;
nvlist_t **child;
uint_t c, children;
verify(nvlist_lookup_uint64(nv, ZPOOL_CONFIG_GUID, &tmp) == 0);
if (tmp == guid)
return (TRUE);
if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN,
&child, &children) == 0) {
for (c = 0; c < children; c++)
if (find_guid(child[c], guid))
return (TRUE);
}
return (FALSE);
}
/*
* Determines if the pool is in use. If so, it returns TRUE and the state of
* the pool as well as the name of the pool. Both strings are allocated and
* must be freed by the caller.
*/
int
zpool_in_use(int fd, pool_state_t *state, char **namestr)
{
nvlist_t *config;
char *name;
int ret;
zfs_cmd_t zc = { 0 };
uint64_t guid, vdev_guid;
zpool_handle_t *zhp;
nvlist_t *pool_config;
uint64_t stateval;
if ((config = zpool_read_label(fd)) == NULL)
return (FALSE);
verify(nvlist_lookup_string(config, ZPOOL_CONFIG_POOL_NAME,
&name) == 0);
verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_STATE,
&stateval) == 0);
verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_POOL_GUID,
&guid) == 0);
verify(nvlist_lookup_uint64(config, ZPOOL_CONFIG_GUID,
&vdev_guid) == 0);
switch (stateval) {
case POOL_STATE_EXPORTED:
ret = TRUE;
break;
case POOL_STATE_ACTIVE:
/*
* For an active pool, we have to determine if it's really part
* of an active pool (in which case the pool will exist and the
* guid will be the same), or whether it's part of an active
* pool that was disconnected without being explicitly exported.
*
* We use the direct ioctl() first to avoid triggering an error
* message if the pool cannot be opened.
*/
(void) strlcpy(zc.zc_name, name, sizeof (zc.zc_name));
if (zfs_ioctl(ZFS_IOC_POOL_GUID, &zc) == 0 &&
guid == zc.zc_guid) {
/*
* Because the device may have been removed while
* offlined, we only report it as active if the vdev is
* still present in the config. Otherwise, pretend like
* it's not in use.
*/
if ((zhp = zpool_open_canfail(name)) != NULL &&
(pool_config = zpool_get_config(zhp, NULL))
!= NULL) {
nvlist_t *nvroot;
verify(nvlist_lookup_nvlist(pool_config,
ZPOOL_CONFIG_VDEV_TREE, &nvroot) == 0);
ret = find_guid(nvroot, vdev_guid);
} else {
ret = FALSE;
}
} else {
stateval = POOL_STATE_POTENTIALLY_ACTIVE;
ret = TRUE;
}
break;
default:
ret = FALSE;
}
if (ret) {
*namestr = zfs_strdup(name);
*state = (pool_state_t)stateval;
}
nvlist_free(config);
return (ret);
}