From 7b4c4781e390a041fa0ef70817678f1b97fc6db6 Mon Sep 17 00:00:00 2001 From: Wenchao Xia Date: Wed, 4 Dec 2013 17:10:54 +0800 Subject: snapshot: distinguish id and name in load_tmp Since later this function will be used so improve it. The only caller of it now is qemu-img, and it is not impacted by introduce function bdrv_snapshot_load_tmp_by_id_or_name() that call bdrv_snapshot_load_tmp() twice to keep old search logic. bdrv_snapshot_load_tmp_by_id_or_name() return int to let caller know the errno, and errno will be used later. Also fix a typo in comments of bdrv_snapshot_delete(). Signed-off-by: Wenchao Xia Signed-off-by: Stefan Hajnoczi --- block/snapshot.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 56 insertions(+), 3 deletions(-) (limited to 'block/snapshot.c') diff --git a/block/snapshot.c b/block/snapshot.c index a05c0c0..565222e 100644 --- a/block/snapshot.c +++ b/block/snapshot.c @@ -194,7 +194,7 @@ int bdrv_snapshot_goto(BlockDriverState *bs, * If only @snapshot_id is specified, delete the first one with id * @snapshot_id. * If only @name is specified, delete the first one with name @name. - * if none is specified, return -ENINVAL. + * if none is specified, return -EINVAL. * * Returns: 0 on success, -errno on failure. If @bs is not inserted, return * -ENOMEDIUM. If @snapshot_id and @name are both NULL, return -EINVAL. If @bs @@ -265,18 +265,71 @@ int bdrv_snapshot_list(BlockDriverState *bs, return -ENOTSUP; } +/** + * Temporarily load an internal snapshot by @snapshot_id and @name. + * @bs: block device used in the operation + * @snapshot_id: unique snapshot ID, or NULL + * @name: snapshot name, or NULL + * @errp: location to store error + * + * If both @snapshot_id and @name are specified, load the first one with + * id @snapshot_id and name @name. + * If only @snapshot_id is specified, load the first one with id + * @snapshot_id. + * If only @name is specified, load the first one with name @name. + * if none is specified, return -EINVAL. + * + * Returns: 0 on success, -errno on fail. If @bs is not inserted, return + * -ENOMEDIUM. If @bs is not readonly, return -EINVAL. If @bs did not support + * internal snapshot, return -ENOTSUP. If qemu can't find a matching @id and + * @name, return -ENOENT. If @errp != NULL, it will always be filled on + * failure. + */ int bdrv_snapshot_load_tmp(BlockDriverState *bs, - const char *snapshot_name) + const char *snapshot_id, + const char *name, + Error **errp) { BlockDriver *drv = bs->drv; + if (!drv) { + error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, bdrv_get_device_name(bs)); return -ENOMEDIUM; } + if (!snapshot_id && !name) { + error_setg(errp, "snapshot_id and name are both NULL"); + return -EINVAL; + } if (!bs->read_only) { + error_setg(errp, "Device is not readonly"); return -EINVAL; } if (drv->bdrv_snapshot_load_tmp) { - return drv->bdrv_snapshot_load_tmp(bs, snapshot_name); + return drv->bdrv_snapshot_load_tmp(bs, snapshot_id, name, errp); } + error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, + drv->format_name, bdrv_get_device_name(bs), + "temporarily load internal snapshot"); return -ENOTSUP; } + +int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs, + const char *id_or_name, + Error **errp) +{ + int ret; + Error *local_err = NULL; + + ret = bdrv_snapshot_load_tmp(bs, id_or_name, NULL, &local_err); + if (ret == -ENOENT || ret == -EINVAL) { + error_free(local_err); + local_err = NULL; + ret = bdrv_snapshot_load_tmp(bs, NULL, id_or_name, &local_err); + } + + if (error_is_set(&local_err)) { + error_propagate(errp, local_err); + } + + return ret; +} -- cgit v1.1