qcow2: Ignore reserved bits in L1/L2 entries

This changes the still existing places that assume that the only flags
are QCOW_OFLAG_COPIED and QCOW_OFLAG_COMPRESSED to properly mask out
reserved bits.

It does not convert bdrv_check yet.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 13 insertions, 13 deletions

diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index dff782fc21..d1602d4bdd 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -195,7 +195,7 @@ static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table)
 
     l2_table = *table;
 
-    if (old_l2_offset == 0) {
+    if ((old_l2_offset & L1E_OFFSET_MASK) == 0) {
         /* if there was no old l2 table, clear the new table */
         memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
     } else {
@@ -203,7 +203,8 @@ static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table)
 
         /* if there was an old l2 table, read it from the disk */
         BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_COW_READ);
-        ret = qcow2_cache_get(bs, s->l2_table_cache, old_l2_offset,
+        ret = qcow2_cache_get(bs, s->l2_table_cache,
+            old_l2_offset & L1E_OFFSET_MASK,
             (void**) &old_table);
         if (ret < 0) {
             goto fail;
@@ -508,13 +509,13 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
             return ret;
         }
     }
-    l2_offset = s->l1_table[l1_index];
+
+    l2_offset = s->l1_table[l1_index] & L1E_OFFSET_MASK;
 
     /* seek the l2 table of the given l2 offset */
 
-    if (l2_offset & QCOW_OFLAG_COPIED) {
+    if (s->l1_table[l1_index] & QCOW_OFLAG_COPIED) {
         /* load the l2 table in memory */
-        l2_offset &= ~QCOW_OFLAG_COPIED;
         ret = l2_load(bs, l2_offset, &l2_table);
         if (ret < 0) {
             return ret;
@@ -530,7 +531,7 @@ static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
         if (l2_offset) {
             qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
         }
-        l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED;
+        l2_offset = s->l1_table[l1_index] & L1E_OFFSET_MASK;
     }
 
     /* find the cluster offset for the given disk offset */
@@ -687,8 +688,7 @@ int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
      */
     if (j != 0) {
         for (i = 0; i < j; i++) {
-            qcow2_free_any_clusters(bs,
-                be64_to_cpu(old_cluster[i]) & ~QCOW_OFLAG_COPIED, 1);
+            qcow2_free_any_clusters(bs, be64_to_cpu(old_cluster[i]), 1);
         }
     }
 
@@ -867,7 +867,9 @@ again:
      * Check how many clusters are already allocated and don't need COW, and how
      * many need a new allocation.
      */
-    if (cluster_offset & QCOW_OFLAG_COPIED) {
+    if (qcow2_get_cluster_type(cluster_offset) == QCOW2_CLUSTER_NORMAL
+        && (cluster_offset & QCOW_OFLAG_COPIED))
+    {
         /* We keep all QCOW_OFLAG_COPIED clusters */
         keep_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size,
                                                   &l2_table[l2_index], 0,
@@ -886,7 +888,7 @@ again:
         cluster_offset = 0;
     }
 
-    cluster_offset &= ~QCOW_OFLAG_COPIED;
+    cluster_offset &= L2E_OFFSET_MASK;
 
     /* If there is something left to allocate, do that now */
     *m = (QCowL2Meta) {
@@ -1041,9 +1043,7 @@ static int discard_single_l2(BlockDriverState *bs, uint64_t offset,
         uint64_t old_offset;
 
         old_offset = be64_to_cpu(l2_table[l2_index + i]);
-        old_offset &= ~QCOW_OFLAG_COPIED;
-
-        if (old_offset == 0) {
+        if ((old_offset & L2E_OFFSET_MASK) == 0) {
             continue;
         }