diff options
| -rw-r--r-- | block/qcow2-cluster.c | 36 |
1 files changed, 22 insertions, 14 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index a86c5a75a9..4c03639a72 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -414,6 +414,10 @@ static int coroutine_fn do_perform_cow(BlockDriverState *bs, struct iovec iov; int ret; + if (bytes == 0) { + return 0; + } + iov.iov_len = bytes; iov.iov_base = qemu_try_blockalign(bs, iov.iov_len); if (iov.iov_base == NULL) { @@ -751,31 +755,40 @@ uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, return cluster_offset; } -static int perform_cow(BlockDriverState *bs, QCowL2Meta *m, Qcow2COWRegion *r) +static int perform_cow(BlockDriverState *bs, QCowL2Meta *m) { BDRVQcow2State *s = bs->opaque; + Qcow2COWRegion *start = &m->cow_start; + Qcow2COWRegion *end = &m->cow_end; int ret; - if (r->nb_bytes == 0) { + if (start->nb_bytes == 0 && end->nb_bytes == 0) { return 0; } qemu_co_mutex_unlock(&s->lock); - ret = do_perform_cow(bs, m->offset, m->alloc_offset, r->offset, r->nb_bytes); - qemu_co_mutex_lock(&s->lock); - + ret = do_perform_cow(bs, m->offset, m->alloc_offset, + start->offset, start->nb_bytes); if (ret < 0) { - return ret; + goto fail; } + ret = do_perform_cow(bs, m->offset, m->alloc_offset, + end->offset, end->nb_bytes); + +fail: + qemu_co_mutex_lock(&s->lock); + /* * Before we update the L2 table to actually point to the new cluster, we * need to be sure that the refcounts have been increased and COW was * handled. */ - qcow2_cache_depends_on_flush(s->l2_table_cache); + if (ret == 0) { + qcow2_cache_depends_on_flush(s->l2_table_cache); + } - return 0; + return ret; } int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m) @@ -795,12 +808,7 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m) } /* copy content of unmodified sectors */ - ret = perform_cow(bs, m, &m->cow_start); - if (ret < 0) { - goto err; - } - - ret = perform_cow(bs, m, &m->cow_end); + ret = perform_cow(bs, m); if (ret < 0) { goto err; } |