@@ -683,6 +683,7 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
for (i = 0; i < m->nb_clusters; i++) {
+ uint64_t offset = cluster_offset + (i << s->cluster_bits);
/* if two concurrent writes happen to the same unallocated cluster
* each write allocates separate cluster and writes data concurrently.
* The first one to complete updates l2 table with pointer to its
@@ -692,8 +693,14 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
if(l2_table[l2_index + i] != 0)
old_cluster[j++] = l2_table[l2_index + i];
- l2_table[l2_index + i] = cpu_to_be64((cluster_offset +
- (i << s->cluster_bits)) | m->l2_entry_flags);
+ l2_table[l2_index + i] = cpu_to_be64(offset | m->l2_entry_flags);
+
+ /* make the deduplication forget the cluster to avoid making
+ * the dedup pointing to a cluster that has changed on it's back.
+ */
+ if (m->to_deduplicate) {
+ qcow2_dedup_forget_cluster_by_sector(bs, offset >> 9);
+ }
}
@@ -869,6 +869,46 @@ static inline bool is_hash_node_empty(QCowHashNode *hash_node)
return hash_node->physical_sect & QCOW_DEDUP_FLAG_EMPTY;
}
+/* This function removes a hash_node from the trees given a physical sector
+ *
+ * @physical_sect: The physical sector of the cluster corresponding to the hash
+ */
+static void qcow2_remove_hash_node_by_sector(BlockDriverState *bs,
+ uint64_t physical_sect)
+{
+ BDRVQcowState *s = bs->opaque;
+ QCowHash hash;
+ int ret = 0;
+ uint8_t *data = qemu_blockalign(bs, s->cluster_sectors * BDRV_SECTOR_SIZE);
+
+
+ /* read the cluster data */
+ ret = bdrv_pread(bs->file, physical_sect << 9, data, s->cluster_size);
+
+ if (ret < 0) {
+ goto free_exit;
+ }
+
+ ret = qcow2_compute_cluster_hash(bs,
+ &hash,
+ data);
+
+ if (ret < 0) {
+ goto free_exit;
+ }
+
+ g_tree_remove(s->dedup_tree_by_hash, &hash);
+
+free_exit:
+ qemu_vfree(data);
+}
+
+void qcow2_dedup_forget_cluster_by_sector(BlockDriverState *bs,
+ uint64_t physical_sect)
+{
+ qcow2_remove_hash_node_by_sector(bs, physical_sect);
+}
+
/* This function store a hash information to disk and RAM
*
* @hash: the QCowHash to process
@@ -467,6 +467,8 @@ int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
/* qcow2-dedup.c functions */
bool qcow2_must_deduplicate(BlockDriverState *bs);
+void qcow2_dedup_forget_cluster_by_sector(BlockDriverState *bs,
+ uint64_t physical_sect);
int qcow2_dedup_read_missing_and_concatenate(BlockDriverState *bs,
QEMUIOVector *qiov,
uint64_t sector,
Signed-off-by: Benoit Canet <benoit@irqsave.net> --- block/qcow2-cluster.c | 11 +++++++++-- block/qcow2-dedup.c | 40 ++++++++++++++++++++++++++++++++++++++++ block/qcow2.h | 2 ++ 3 files changed, 51 insertions(+), 2 deletions(-)