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| author | edison <edison@cloud.com> | 2010-09-21 19:58:41 -0700 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2010-10-22 14:49:35 +0200 |
| commit | 51ef67270b1d10e1fcf3de7368dccad1ba0bf9d1 (patch) | |
| tree | a06b3ce03bae7ed77a1e1e9bebc6ead157c7a4e5 /block | |
| parent | a58b8d5401b6064d52113f243456115d046bdd12 (diff) | |
| download | qemu-51ef67270b1d10e1fcf3de7368dccad1ba0bf9d1.zip qemu-51ef67270b1d10e1fcf3de7368dccad1ba0bf9d1.tar.gz qemu-51ef67270b1d10e1fcf3de7368dccad1ba0bf9d1.tar.bz2 | |
Copy snapshots out of QCOW2 disk
In order to backup snapshots, created from QCOW2 iamge, we want to copy snapshots out of QCOW2 disk to a seperate storage.
The following patch adds a new option in "qemu-img": qemu-img convert -f qcow2 -O qcow2 -s snapshot_name src_img bck_img.
Right now, it only supports to copy the full snapshot, delta snapshot is on the way.
Changes from V1: all the comments from Kevin are addressed:
Add read-only checking
Fix coding style
Change the name from bdrv_snapshot_load to bdrv_snapshot_load_tmp
Signed-off-by: Disheng Su <edison@cloud.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/qcow2-snapshot.c | 31 | ||||
| -rw-r--r-- | block/qcow2.c | 1 | ||||
| -rw-r--r-- | block/qcow2.h | 1 |
3 files changed, 33 insertions, 0 deletions
diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index 8dd5df0..aacf357 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -418,3 +418,34 @@ 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 i, snapshot_index, l1_size2; + BDRVQcowState *s = bs->opaque; + QCowSnapshot *sn; + + snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_name); + if (snapshot_index < 0) { + return -ENOENT; + } + + sn = &s->snapshots[snapshot_index]; + s->l1_size = sn->l1_size; + l1_size2 = s->l1_size * sizeof(uint64_t); + if (s->l1_table != NULL) { + qemu_free(s->l1_table); + } + + s->l1_table_offset = sn->l1_table_offset; + s->l1_table = qemu_mallocz(align_offset(l1_size2, 512)); + + if (bdrv_pread(bs->file, sn->l1_table_offset, + s->l1_table, l1_size2) != l1_size2) { + return -1; + } + + for(i = 0;i < s->l1_size; i++) { + be64_to_cpus(&s->l1_table[i]); + } + return 0; +} diff --git a/block/qcow2.c b/block/qcow2.c index 45ed073..b816d87 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1286,6 +1286,7 @@ static BlockDriver bdrv_qcow2 = { .bdrv_snapshot_goto = qcow2_snapshot_goto, .bdrv_snapshot_delete = qcow2_snapshot_delete, .bdrv_snapshot_list = qcow2_snapshot_list, + .bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp, .bdrv_get_info = qcow_get_info, .bdrv_save_vmstate = qcow_save_vmstate, diff --git a/block/qcow2.h b/block/qcow2.h index add710b..2d22e5e 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -211,6 +211,7 @@ int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info); int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id); int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id); int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab); +int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name); void qcow2_free_snapshots(BlockDriverState *bs); int qcow2_read_snapshots(BlockDriverState *bs); |