diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2011-01-26 16:56:48 +0100 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2011-01-31 10:03:00 +0100 |
| commit | 5ea929e3d13622e5d06ca8795819f1590644cda2 (patch) | |
| tree | 1aba3562b30cf62ac6a8fdc5f313f4a90e816c88 /block/qcow2.c | |
| parent | a9c49a6b023fd3706002fd8d549c58f0343932f8 (diff) | |
| download | qemu-5ea929e3d13622e5d06ca8795819f1590644cda2.tar.gz | |
qcow2: Add bdrv_discard support
This adds a bdrv_discard function to qcow2 that frees the discarded clusters.
It does not yet pass the discard on to the underlying file system driver, but
the space can be reused by future writes to the image.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Diffstat (limited to 'block/qcow2.c')
| -rw-r--r-- | block/qcow2.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/block/qcow2.c b/block/qcow2.c index 49bf7b9d3d..dbe4fdd44d 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1084,6 +1084,13 @@ static int qcow2_make_empty(BlockDriverState *bs) return 0; } +static int qcow2_discard(BlockDriverState *bs, int64_t sector_num, + int nb_sectors) +{ + return qcow2_discard_clusters(bs, sector_num << BDRV_SECTOR_BITS, + nb_sectors); +} + static int qcow2_truncate(BlockDriverState *bs, int64_t offset) { BDRVQcowState *s = bs->opaque; @@ -1349,6 +1356,7 @@ static BlockDriver bdrv_qcow2 = { .bdrv_aio_writev = qcow2_aio_writev, .bdrv_aio_flush = qcow2_aio_flush, + .bdrv_discard = qcow2_discard, .bdrv_truncate = qcow2_truncate, .bdrv_write_compressed = qcow2_write_compressed, |