/*
* Given a file descriptor, clear (zero) the label information. This function
* is used in the appliance stack as part of the ZFS sysevent module and
* to implement the "zpool labelclear" command.
*/
int
zpool_clear_label(int fd)
{
struct stat64 statbuf;
int l;
vdev_label_t *label;
uint64_t size;
if (fstat64_blk(fd, &statbuf) == -1)
return (0);
size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
if ((label = calloc(sizeof (vdev_label_t), 1)) == NULL)
return (-1);
for (l = 0; l < VDEV_LABELS; l++) {
if (pwrite64(fd, label, sizeof (vdev_label_t),
label_offset(size, l)) != sizeof (vdev_label_t)) {
free(label);
return (-1);
}
}
free(label);
return (0);
}
/*
* Given a file descriptor, read the label information and return an nvlist
* describing the configuration, if there is one.
*/
int
zpool_read_label(int fd, nvlist_t **config)
{
struct stat64 statbuf;
int l;
vdev_label_t *label;
uint64_t state, txg, size;
*config = NULL;
if (fstat64_blk(fd, &statbuf) == -1)
return (0);
size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
if ((label = malloc(sizeof (vdev_label_t))) == NULL)
return (-1);
for (l = 0; l < VDEV_LABELS; l++) {
if (pread64(fd, label, sizeof (vdev_label_t),
label_offset(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_L2CACHE) {
nvlist_free(*config);
continue;
}
if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
(nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
&txg) != 0 || txg == 0)) {
nvlist_free(*config);
continue;
}
free(label);
return (0);
}
free(label);
*config = NULL;
return (0);
}
/*
* Given a file descriptor, read the label information and return an nvlist
* describing the configuration, if there is one. The number of valid
* labels found will be returned in num_labels when non-NULL.
*/
int
zpool_read_label(int fd, nvlist_t **config, int *num_labels)
{
struct stat64 statbuf;
int l, count = 0;
vdev_label_t *label;
nvlist_t *expected_config = NULL;
uint64_t expected_guid = 0, size;
*config = NULL;
if (fstat64_blk(fd, &statbuf) == -1)
return (0);
size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
if ((label = malloc(sizeof (vdev_label_t))) == NULL)
return (-1);
for (l = 0; l < VDEV_LABELS; l++) {
uint64_t state, guid, txg;
if (pread64(fd, label, sizeof (vdev_label_t),
label_offset(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_GUID,
&guid) != 0 || guid == 0) {
nvlist_free(*config);
continue;
}
if (nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_STATE,
&state) != 0 || state > POOL_STATE_L2CACHE) {
nvlist_free(*config);
continue;
}
if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
(nvlist_lookup_uint64(*config, ZPOOL_CONFIG_POOL_TXG,
&txg) != 0 || txg == 0)) {
nvlist_free(*config);
continue;
}
if (expected_guid) {
if (expected_guid == guid)
count++;
nvlist_free(*config);
} else {
expected_config = *config;
expected_guid = guid;
count++;
}
}
if (num_labels != NULL)
*num_labels = count;
free(label);
*config = expected_config;
return (0);
}