On 14.10.2013 23:52, Wenchao Xia wrote:
> The function still returns int since qcow2_snapshot_delete() will
> return the number.
>
> Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com>
> ---
> block/qcow2-snapshot.c | 48
> ++++++++++++++++++++++++++++++++++++++++++------
> 1 files changed, 42 insertions(+), 6 deletions(-)
>
> diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c
> index b373f9a..4bd494b 100644
> --- a/block/qcow2-snapshot.c
> +++ b/block/qcow2-snapshot.c
> @@ -152,7 +152,7 @@ fail:
> }
>
> /* add at the end of the file a new list of snapshots */
> -static int qcow2_write_snapshots(BlockDriverState *bs)
> +static int qcow2_write_snapshots(BlockDriverState *bs, Error **errp)
> {
> BDRVQcowState *s = bs->opaque;
> QCowSnapshot *sn;
> @@ -183,10 +183,18 @@ static int qcow2_write_snapshots(BlockDriverState *bs)
> offset = snapshots_offset;
> if (offset < 0) {
> ret = offset;
> + error_setg(errp,
> + "Failed in allocation of cluster for snapshot list: "
> + "%d (%s)",
> + ret, strerror(-ret));
Again, error_setg_errno() is your friend.
> goto fail;
> }
> ret = bdrv_flush(bs);
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in flush after snapshot list cluster allocation: "
> + "%d (%s)",
> + ret, strerror(-ret));
> goto fail;
> }
>
> @@ -194,6 +202,10 @@ static int qcow2_write_snapshots(BlockDriverState *bs)
> * must indeed be completely free */
> ret = qcow2_pre_write_overlap_check(bs, 0, offset, snapshots_size);
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in overlap check for snapshot list cluster at %"
> + PRIi64 " with size %d: %d (%s)",
> + offset, snapshots_size, ret, strerror(-ret));
> goto fail;
> }
>
> @@ -227,24 +239,40 @@ static int qcow2_write_snapshots(BlockDriverState *bs)
>
> ret = bdrv_pwrite(bs->file, offset, &h, sizeof(h));
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in write of snapshot header at %"
> + PRIi64 " with size %" PRIu64 ": %d (%s)",
> + offset, sizeof(h), ret, strerror(-ret));
Again, on 32 bit systems, sizeof(size_t) is generally 4 and not 8 (you
may want to cast sizeof(h) to int and just use %d).
> goto fail;
> }
> offset += sizeof(h);
>
> ret = bdrv_pwrite(bs->file, offset, &extra, sizeof(extra));
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in write of extra snapshot data at %"
> + PRIi64 " with size %" PRIu64 ": %d (%s)",
> + offset, sizeof(extra), ret, strerror(-ret));
Same here.
> goto fail;
> }
> offset += sizeof(extra);
>
> ret = bdrv_pwrite(bs->file, offset, sn->id_str, id_str_size);
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in write of snapshot id string at %"
> + PRIi64 " with size %d: %d (%s)",
> + offset, id_str_size, ret, strerror(-ret));
> goto fail;
> }
> offset += id_str_size;
>
> ret = bdrv_pwrite(bs->file, offset, sn->name, name_size);
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in write of snapshot name string at %"
> + PRIi64 " with size %d: %d (%s)",
> + offset, name_size, ret, strerror(-ret));
> goto fail;
> }
> offset += name_size;
> @@ -256,6 +284,9 @@ static int qcow2_write_snapshots(BlockDriverState *bs)
> */
> ret = bdrv_flush(bs);
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in flush after snapshot list update: %d (%s)",
> + ret, strerror(-ret));
> goto fail;
> }
>
> @@ -268,6 +299,11 @@ static int qcow2_write_snapshots(BlockDriverState *bs)
> ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, nb_snapshots),
> &header_data, sizeof(header_data));
> if (ret < 0) {
> + error_setg(errp,
> + "Failed in update of image header at %"
> + PRIi64 " with size %" PRIu64 ":%d (%s)",
> + offsetof(QCowHeader, nb_snapshots), sizeof(header_data),
> + ret, strerror(-ret));
And here (also applies to offsetof(), which returns size_t as well).
Also, you forgot a space after the colon (although you should be using
error_setg_errno() anyway).
Max
> goto fail;
> }
>
> @@ -283,6 +319,9 @@ fail:
> qcow2_free_clusters(bs, snapshots_offset, snapshots_size,
> QCOW2_DISCARD_ALWAYS);
> }
> + if (errp) {
> + g_assert(error_is_set(errp));
> + }
> return ret;
> }
>
> @@ -446,10 +485,8 @@ void qcow2_snapshot_create(BlockDriverState *bs,
> s->snapshots = new_snapshot_list;
> s->snapshots[s->nb_snapshots++] = *sn;
>
> - ret = qcow2_write_snapshots(bs);
> + ret = qcow2_write_snapshots(bs, errp);
> if (ret < 0) {
> - /* Following line will be replaced with more detailed error later */
> - error_setg(errp, "Failed in write of snapshot");
> g_free(s->snapshots);
> s->snapshots = old_snapshot_list;
> s->nb_snapshots--;
> @@ -623,9 +660,8 @@ int qcow2_snapshot_delete(BlockDriverState *bs,
> s->snapshots + snapshot_index + 1,
> (s->nb_snapshots - snapshot_index - 1) * sizeof(sn));
> s->nb_snapshots--;
> - ret = qcow2_write_snapshots(bs);
> + ret = qcow2_write_snapshots(bs, errp);
> if (ret < 0) {
> - error_setg(errp, "Failed to remove snapshot from snapshot list");
> return ret;
> }
>
