qcow2: Allow alloc_clusters_noref to return errors

Currently it would consider blocks for which get_refcount fails used. However,
it's unlikely that get_refcount would succeed for the next cluster, so it's not
really helpful. Return an error instead.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2010-06-04 11:22:39 +02:00
parent 018faafdbd
commit 2eaa8f6338

View File

@ -228,7 +228,10 @@ static int64_t alloc_refcount_block(BlockDriverState *bs, int64_t cluster_index)
}
/* Allocate the refcount block itself and mark it as used */
uint64_t new_block = alloc_clusters_noref(bs, s->cluster_size);
int64_t new_block = alloc_clusters_noref(bs, s->cluster_size);
if (new_block < 0) {
return new_block;
}
#ifdef DEBUG_ALLOC2
fprintf(stderr, "qcow2: Allocate refcount block %d for %" PRIx64
@ -579,15 +582,20 @@ static int update_cluster_refcount(BlockDriverState *bs,
static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
{
BDRVQcowState *s = bs->opaque;
int i, nb_clusters;
int i, nb_clusters, refcount;
nb_clusters = size_to_clusters(s, size);
retry:
for(i = 0; i < nb_clusters; i++) {
int64_t next_cluster_index = s->free_cluster_index++;
if (get_refcount(bs, next_cluster_index) != 0)
refcount = get_refcount(bs, next_cluster_index);
if (refcount < 0) {
return refcount;
} else if (refcount != 0) {
goto retry;
}
}
#ifdef DEBUG_ALLOC2
printf("alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n",
size,
@ -603,6 +611,10 @@ int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size)
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC);
offset = alloc_clusters_noref(bs, size);
if (offset < 0) {
return offset;
}
ret = update_refcount(bs, offset, size, 1);
if (ret < 0) {
return ret;