diff options
| author | Max Reitz <mreitz@redhat.com> | 2013-09-03 10:09:52 +0200 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2013-09-12 10:12:46 +0200 |
| commit | 32b6444d23d0ff618d73e5b766600cd258066169 (patch) | |
| tree | 423a268eaa2281d71e0d7d1d75ade22e153510aa /block/qcow2-refcount.c | |
| parent | e7108feaace8e02b3a4bf010448fc2744f753381 (diff) | |
qcow2-cluster: Expand zero clusters
Add functionality for expanding zero clusters. This is necessary for
downgrading the image version to one without zero cluster support.
For non-backed images, this function may also just discard zero clusters
instead of truly expanding them.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block/qcow2-refcount.c')
| -rw-r--r-- | block/qcow2-refcount.c | 29 |
1 files changed, 15 insertions, 14 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index ba129de478..4264148142 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -601,10 +601,10 @@ fail: * If the return value is non-negative, it is the new refcount of the cluster. * If it is negative, it is -errno and indicates an error. */ -static int update_cluster_refcount(BlockDriverState *bs, - int64_t cluster_index, - int addend, - enum qcow2_discard_type type) +int qcow2_update_cluster_refcount(BlockDriverState *bs, + int64_t cluster_index, + int addend, + enum qcow2_discard_type type) { BDRVQcowState *s = bs->opaque; int ret; @@ -733,8 +733,8 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size) if (free_in_cluster == 0) s->free_byte_offset = 0; if ((offset & (s->cluster_size - 1)) != 0) - update_cluster_refcount(bs, offset >> s->cluster_bits, 1, - QCOW2_DISCARD_NEVER); + qcow2_update_cluster_refcount(bs, offset >> s->cluster_bits, 1, + QCOW2_DISCARD_NEVER); } else { offset = qcow2_alloc_clusters(bs, s->cluster_size); if (offset < 0) { @@ -744,8 +744,8 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size) if ((cluster_offset + s->cluster_size) == offset) { /* we are lucky: contiguous data */ offset = s->free_byte_offset; - update_cluster_refcount(bs, offset >> s->cluster_bits, 1, - QCOW2_DISCARD_NEVER); + qcow2_update_cluster_refcount(bs, offset >> s->cluster_bits, 1, + QCOW2_DISCARD_NEVER); s->free_byte_offset += size; } else { s->free_byte_offset = offset; @@ -754,8 +754,8 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size) } /* The cluster refcount was incremented, either by qcow2_alloc_clusters() - * or explicitly by update_cluster_refcount(). Refcount blocks must be - * flushed before the caller's L2 table updates. + * or explicitly by qcow2_update_cluster_refcount(). Refcount blocks must + * be flushed before the caller's L2 table updates. */ qcow2_cache_set_dependency(bs, s->l2_table_cache, s->refcount_block_cache); return offset; @@ -896,8 +896,9 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, break; } if (addend != 0) { - refcount = update_cluster_refcount(bs, cluster_index, addend, - QCOW2_DISCARD_SNAPSHOT); + refcount = qcow2_update_cluster_refcount(bs, + cluster_index, addend, + QCOW2_DISCARD_SNAPSHOT); } else { refcount = get_refcount(bs, cluster_index); } @@ -936,8 +937,8 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs, if (addend != 0) { - refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend, - QCOW2_DISCARD_SNAPSHOT); + refcount = qcow2_update_cluster_refcount(bs, l2_offset >> + s->cluster_bits, addend, QCOW2_DISCARD_SNAPSHOT); } else { refcount = get_refcount(bs, l2_offset >> s->cluster_bits); } |