diff options
| author | Fam Zheng <famcool@gmail.com> | 2011-07-12 19:56:29 +0800 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2011-07-19 15:39:06 +0200 |
| commit | 0e69c543946957fe8450ebb13874bb1ef280d55b (patch) | |
| tree | 0c477bf0bcbbfb10c6681ced70f34570312c7c38 /block | |
| parent | b3976d3c8b895e8929d133b80ef5e373b60cf357 (diff) | |
VMDK: bugfix, align offset to cluster in get_whole_cluster
In get_whole_cluster, the offset is not aligned to cluster when reading
from backing_hd. When the first write to child is not at the cluster
boundary, wrong address data from parent is copied to child.
Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/vmdk.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/block/vmdk.c b/block/vmdk.c index 3b78583a8a..03a4619201 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -514,21 +514,23 @@ static int get_whole_cluster(BlockDriverState *bs, /* 128 sectors * 512 bytes each = grain size 64KB */ uint8_t whole_grain[extent->cluster_sectors * 512]; - // we will be here if it's first write on non-exist grain(cluster). - // try to read from parent image, if exist + /* we will be here if it's first write on non-exist grain(cluster). + * try to read from parent image, if exist */ if (bs->backing_hd) { int ret; if (!vmdk_is_cid_valid(bs)) return -1; + /* floor offset to cluster */ + offset -= offset % (extent->cluster_sectors * 512); ret = bdrv_read(bs->backing_hd, offset >> 9, whole_grain, extent->cluster_sectors); if (ret < 0) { return -1; } - //Write grain only into the active image + /* Write grain only into the active image */ ret = bdrv_write(extent->file, cluster_offset, whole_grain, extent->cluster_sectors); if (ret < 0) { |