diff options
| -rw-r--r-- | block/qcow2-cluster.c | 38 |
1 files changed, 27 insertions, 11 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index cab5f2e6b5..ffa89411d8 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1510,8 +1510,8 @@ fail: * i.e., the number of bits in expanded_clusters. */ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, - int l1_size, uint8_t *expanded_clusters, - uint64_t nb_clusters) + int l1_size, uint8_t **expanded_clusters, + uint64_t *nb_clusters) { BDRVQcowState *s = bs->opaque; bool is_active_l1 = (l1_table == s->l1_table); @@ -1554,8 +1554,8 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, if (cluster_type == QCOW2_CLUSTER_NORMAL) { cluster_index = offset >> s->cluster_bits; - assert((cluster_index >= 0) && (cluster_index < nb_clusters)); - if (expanded_clusters[cluster_index / 8] & + assert((cluster_index >= 0) && (cluster_index < *nb_clusters)); + if ((*expanded_clusters)[cluster_index / 8] & (1 << (cluster_index % 8))) { /* Probably a shared L2 table; this cluster was a zero * cluster which has been expanded, its refcount @@ -1613,8 +1613,25 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, l2_dirty = true; cluster_index = offset >> s->cluster_bits; - assert((cluster_index >= 0) && (cluster_index < nb_clusters)); - expanded_clusters[cluster_index / 8] |= 1 << (cluster_index % 8); + + if (cluster_index >= *nb_clusters) { + uint64_t old_bitmap_size = (*nb_clusters + 7) / 8; + uint64_t new_bitmap_size; + /* The offset may lie beyond the old end of the underlying image + * file for growable files only */ + assert(bs->file->growable); + *nb_clusters = size_to_clusters(s, bs->file->total_sectors * + BDRV_SECTOR_SIZE); + new_bitmap_size = (*nb_clusters + 7) / 8; + *expanded_clusters = g_realloc(*expanded_clusters, + new_bitmap_size); + /* clear the newly allocated space */ + memset(&(*expanded_clusters)[old_bitmap_size], 0, + new_bitmap_size - old_bitmap_size); + } + + assert((cluster_index >= 0) && (cluster_index < *nb_clusters)); + (*expanded_clusters)[cluster_index / 8] |= 1 << (cluster_index % 8); } if (is_active_l1) { @@ -1673,18 +1690,17 @@ int qcow2_expand_zero_clusters(BlockDriverState *bs) { BDRVQcowState *s = bs->opaque; uint64_t *l1_table = NULL; - int cluster_to_sector_bits = s->cluster_bits - BDRV_SECTOR_BITS; uint64_t nb_clusters; uint8_t *expanded_clusters; int ret; int i, j; - nb_clusters = (bs->total_sectors + (1 << cluster_to_sector_bits) - 1) - >> cluster_to_sector_bits; + nb_clusters = size_to_clusters(s, bs->file->total_sectors * + BDRV_SECTOR_SIZE); expanded_clusters = g_malloc0((nb_clusters + 7) / 8); ret = expand_zero_clusters_in_l1(bs, s->l1_table, s->l1_size, - expanded_clusters, nb_clusters); + &expanded_clusters, &nb_clusters); if (ret < 0) { goto fail; } @@ -1718,7 +1734,7 @@ int qcow2_expand_zero_clusters(BlockDriverState *bs) } ret = expand_zero_clusters_in_l1(bs, l1_table, s->snapshots[i].l1_size, - expanded_clusters, nb_clusters); + &expanded_clusters, &nb_clusters); if (ret < 0) { goto fail; } |