From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55056) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VfkbU-0008SI-V0 for qemu-devel@nongnu.org; Mon, 11 Nov 2013 01:04:14 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VfkbL-0002OS-Vr for qemu-devel@nongnu.org; Mon, 11 Nov 2013 01:04:04 -0500 Received: from e28smtp03.in.ibm.com ([122.248.162.3]:45667) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VfkbL-0002O1-36 for qemu-devel@nongnu.org; Mon, 11 Nov 2013 01:03:55 -0500 Received: from /spool/local by e28smtp03.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 11 Nov 2013 11:33:51 +0530 Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by d28dlp03.in.ibm.com (Postfix) with ESMTP id D2C551258051 for ; Mon, 11 Nov 2013 11:34:36 +0530 (IST) Received: from d28av02.in.ibm.com (d28av02.in.ibm.com [9.184.220.64]) by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id rAB63ldd39649450 for ; Mon, 11 Nov 2013 11:33:47 +0530 Received: from d28av02.in.ibm.com (localhost [127.0.0.1]) by d28av02.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id rAB63mL8003149 for ; Mon, 11 Nov 2013 11:33:49 +0530 From: Wenchao Xia Date: Mon, 11 Nov 2013 06:03:36 +0800 Message-Id: <1384121021-24815-2-git-send-email-xiawenc@linux.vnet.ibm.com> In-Reply-To: <1384121021-24815-1-git-send-email-xiawenc@linux.vnet.ibm.com> References: <1384121021-24815-1-git-send-email-xiawenc@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH V5 1/5] snapshot: distinguish id and name in load_tmp List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, jcody@redhat.com, stefanha@redhat.com, pbonzini@redhat.com, Wenchao Xia 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 --- block/qcow2-snapshot.c | 16 ++++++++++- block/qcow2.h | 5 +++- block/snapshot.c | 60 ++++++++++++++++++++++++++++++++++++++++++-- include/block/block_int.h | 4 ++- include/block/snapshot.h | 7 ++++- qemu-img.c | 8 ++++- 6 files changed, 90 insertions(+), 10 deletions(-) diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index 3529c68..aeb5efd 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -675,7 +675,10 @@ int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab) return s->nb_snapshots; } -int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name) +int qcow2_snapshot_load_tmp(BlockDriverState *bs, + const char *snapshot_id, + const char *name, + Error **errp) { int i, snapshot_index; BDRVQcowState *s = bs->opaque; @@ -683,12 +686,17 @@ int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name) uint64_t *new_l1_table; int new_l1_bytes; int ret; + const char *device = bdrv_get_device_name(bs); assert(bs->read_only); /* Search the snapshot */ - snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_name); + snapshot_index = find_snapshot_by_id_and_name(bs, snapshot_id, name); if (snapshot_index < 0) { + error_setg(errp, + "Can't find a snapshot with ID '%s' and name '%s' " + "on device '%s'", + STR_OR_NULL(snapshot_id), STR_OR_NULL(name), device); return -ENOENT; } sn = &s->snapshots[snapshot_index]; @@ -699,6 +707,10 @@ int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name) ret = bdrv_pread(bs->file, sn->l1_table_offset, new_l1_table, new_l1_bytes); if (ret < 0) { + error_setg(errp, + "Failed to read l1 table for snapshot with ID '%s' and name " + "'%s' on device '%s'", + sn->id_str, sn->name, device); g_free(new_l1_table); return ret; } diff --git a/block/qcow2.h b/block/qcow2.h index 922e190..303eb26 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -488,7 +488,10 @@ int qcow2_snapshot_delete(BlockDriverState *bs, const char *name, Error **errp); int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab); -int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name); +int qcow2_snapshot_load_tmp(BlockDriverState *bs, + const char *snapshot_id, + const char *name, + Error **errp); void qcow2_free_snapshots(BlockDriverState *bs); int qcow2_read_snapshots(BlockDriverState *bs); diff --git a/block/snapshot.c b/block/snapshot.c index a05c0c0..e51a7db 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 +265,72 @@ 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 one matching @id and + * @name, return -ENOENT. If @bs does not support parameter @snapshot_id or + * @name, return -EINVAL. 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; + const char *device = bdrv_get_device_name(bs); if (!drv) { + error_set(errp, QERR_DEVICE_HAS_NO_MEDIUM, device); 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 '%s' is not readonly", device); 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, device, + "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; +} diff --git a/include/block/block_int.h b/include/block/block_int.h index 1666066..8bbfb09 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -175,7 +175,9 @@ struct BlockDriver { int (*bdrv_snapshot_list)(BlockDriverState *bs, QEMUSnapshotInfo **psn_info); int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, - const char *snapshot_name); + const char *snapshot_id, + const char *name, + Error **errp); int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs); diff --git a/include/block/snapshot.h b/include/block/snapshot.h index 012bf22..d05bea7 100644 --- a/include/block/snapshot.h +++ b/include/block/snapshot.h @@ -61,5 +61,10 @@ void bdrv_snapshot_delete_by_id_or_name(BlockDriverState *bs, int bdrv_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_info); int bdrv_snapshot_load_tmp(BlockDriverState *bs, - const char *snapshot_name); + const char *snapshot_id, + const char *name, + Error **errp); +int bdrv_snapshot_load_tmp_by_id_or_name(BlockDriverState *bs, + const char *id_or_name, + Error **errp); #endif diff --git a/qemu-img.c b/qemu-img.c index bf3fb4f..fe28119 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1260,8 +1260,12 @@ static int img_convert(int argc, char **argv) ret = -1; goto out; } - if (bdrv_snapshot_load_tmp(bs[0], snapshot_name) < 0) { - error_report("Failed to load snapshot"); + + bdrv_snapshot_load_tmp_by_id_or_name(bs[0], snapshot_name, &local_err); + if (error_is_set(&local_err)) { + error_report("Failed to load snapshot: %s", + error_get_pretty(local_err)); + error_free(local_err); ret = -1; goto out; } -- 1.7.1