diff options
| -rw-r--r-- | drivers/md/dm-ioctl.c | 103 | ||||
| -rw-r--r-- | include/linux/dm-ioctl.h | 12 |
2 files changed, 87 insertions, 28 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 4b54618b415..f3481d92220 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -295,19 +295,55 @@ retry: DMWARN("remove_all left %d open device(s)", dev_skipped); } +/* + * Set the uuid of a hash_cell that isn't already set. + */ +static void __set_cell_uuid(struct hash_cell *hc, char *new_uuid) +{ + mutex_lock(&dm_hash_cells_mutex); + hc->uuid = new_uuid; + mutex_unlock(&dm_hash_cells_mutex); + + list_add(&hc->uuid_list, _uuid_buckets + hash_str(new_uuid)); +} + +/* + * Changes the name of a hash_cell and returns the old name for + * the caller to free. + */ +static char *__change_cell_name(struct hash_cell *hc, char *new_name) +{ + char *old_name; + + /* + * Rename and move the name cell. + */ + list_del(&hc->name_list); + old_name = hc->name; + + mutex_lock(&dm_hash_cells_mutex); + hc->name = new_name; + mutex_unlock(&dm_hash_cells_mutex); + + list_add(&hc->name_list, _name_buckets + hash_str(new_name)); + + return old_name; +} + static struct mapped_device *dm_hash_rename(struct dm_ioctl *param, const char *new) { - char *new_name, *old_name; + char *new_data, *old_name = NULL; struct hash_cell *hc; struct dm_table *table; struct mapped_device *md; + unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0; /* * duplicate new. */ - new_name = kstrdup(new, GFP_KERNEL); - if (!new_name) + new_data = kstrdup(new, GFP_KERNEL); + if (!new_data) return ERR_PTR(-ENOMEM); down_write(&_hash_lock); @@ -315,13 +351,19 @@ static struct mapped_device *dm_hash_rename(struct dm_ioctl *param, /* * Is new free ? */ - hc = __get_name_cell(new); + if (change_uuid) + hc = __get_uuid_cell(new); + else + hc = __get_name_cell(new); + if (hc) { - DMWARN("asked to rename to an already-existing name %s -> %s", + DMWARN("Unable to change %s on mapped device %s to one that " + "already exists: %s", + change_uuid ? "uuid" : "name", param->name, new); dm_put(hc->md); up_write(&_hash_lock); - kfree(new_name); + kfree(new_data); return ERR_PTR(-EBUSY); } @@ -330,22 +372,30 @@ static struct mapped_device *dm_hash_rename(struct dm_ioctl *param, */ hc = __get_name_cell(param->name); if (!hc) { - DMWARN("asked to rename a non-existent device %s -> %s", - param->name, new); + DMWARN("Unable to rename non-existent device, %s to %s%s", + param->name, change_uuid ? "uuid " : "", new); up_write(&_hash_lock); - kfree(new_name); + kfree(new_data); return ERR_PTR(-ENXIO); } /* - * rename and move the name cell. + * Does this device already have a uuid? */ - list_del(&hc->name_list); - old_name = hc->name; - mutex_lock(&dm_hash_cells_mutex); - hc->name = new_name; - mutex_unlock(&dm_hash_cells_mutex); - list_add(&hc->name_list, _name_buckets + hash_str(new_name)); + if (change_uuid && hc->uuid) { + DMWARN("Unable to change uuid of mapped device %s to %s " + "because uuid is already set to %s", + param->name, new, hc->uuid); + dm_put(hc->md); + up_write(&_hash_lock); + kfree(new_data); + return ERR_PTR(-EINVAL); + } + + if (change_uuid) + __set_cell_uuid(hc, new_data); + else + old_name = __change_cell_name(hc, new_data); /* * Wake up any dm event waiters. @@ -774,21 +824,24 @@ static int invalid_str(char *str, void *end) static int dev_rename(struct dm_ioctl *param, size_t param_size) { int r; - char *new_name = (char *) param + param->data_start; + char *new_data = (char *) param + param->data_start; struct mapped_device *md; + unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0; - if (new_name < param->data || - invalid_str(new_name, (void *) param + param_size) || - strlen(new_name) > DM_NAME_LEN - 1) { - DMWARN("Invalid new logical volume name supplied."); + if (new_data < param->data || + invalid_str(new_data, (void *) param + param_size) || + strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) { + DMWARN("Invalid new mapped device name or uuid string supplied."); return -EINVAL; } - r = check_name(new_name); - if (r) - return r; + if (!change_uuid) { + r = check_name(new_data); + if (r) + return r; + } - md = dm_hash_rename(param, new_name); + md = dm_hash_rename(param, new_data); if (IS_ERR(md)) return PTR_ERR(md); diff --git a/include/linux/dm-ioctl.h b/include/linux/dm-ioctl.h index 49eab360d5d..e453e1174ae 100644 --- a/include/linux/dm-ioctl.h +++ b/include/linux/dm-ioctl.h @@ -44,7 +44,7 @@ * Remove a device, destroy any tables. * * DM_DEV_RENAME: - * Rename a device. + * Rename a device or set its uuid if none was previously supplied. * * DM_SUSPEND: * This performs both suspend and resume, depending which flag is @@ -267,9 +267,9 @@ enum { #define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl) #define DM_VERSION_MAJOR 4 -#define DM_VERSION_MINOR 18 +#define DM_VERSION_MINOR 19 #define DM_VERSION_PATCHLEVEL 0 -#define DM_VERSION_EXTRA "-ioctl (2010-06-29)" +#define DM_VERSION_EXTRA "-ioctl (2010-10-14)" /* Status bits */ #define DM_READONLY_FLAG (1 << 0) /* In/Out */ @@ -322,4 +322,10 @@ enum { */ #define DM_UEVENT_GENERATED_FLAG (1 << 13) /* Out */ +/* + * If set, rename changes the uuid not the name. Only permitted + * if no uuid was previously supplied: an existing uuid cannot be changed. + */ +#define DM_UUID_FLAG (1 << 14) /* In */ + #endif /* _LINUX_DM_IOCTL_H */ |