1 files changed, 10 insertions, 4 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index e3c6bfea375..a366415e03a 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -443,6 +443,7 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
         buf_leaf = btrfs_buffer_leaf(buf);
         for (i = 0; i < btrfs_header_nritems(&buf_node->header); i++) {
                 if (leaf) {
+                        u64 disk_blocknr;
                         key = &buf_leaf->items[i].key;
                         if (btrfs_disk_key_type(key) != BTRFS_EXTENT_DATA_KEY)
                                 continue;
@@ -451,8 +452,10 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                         if (btrfs_file_extent_type(fi) ==
                             BTRFS_FILE_EXTENT_INLINE)
                                 continue;
-                        ret = btrfs_inc_extent_ref(trans, root,
-                                    btrfs_file_extent_disk_blocknr(fi),
+                        disk_blocknr = btrfs_file_extent_disk_blocknr(fi);
+                        if (disk_blocknr == 0)
+                                continue;
+                        ret = btrfs_inc_extent_ref(trans, root, disk_blocknr,
                                     btrfs_file_extent_disk_num_blocks(fi));
                         BUG_ON(ret);
                 } else {
@@ -1248,6 +1251,7 @@ static int drop_leaf_ref(struct btrfs_trans_handle *trans,
         leaf = btrfs_buffer_leaf(cur);
         nritems = btrfs_header_nritems(&leaf->header);
         for (i = 0; i < nritems; i++) {
+                u64 disk_blocknr;
                 key = &leaf->items[i].key;
                 if (btrfs_disk_key_type(key) != BTRFS_EXTENT_DATA_KEY)
                         continue;
@@ -1258,8 +1262,10 @@ static int drop_leaf_ref(struct btrfs_trans_handle *trans,
                  * FIXME make sure to insert a trans record that
                  * repeats the snapshot del on crash
                  */
-                ret = btrfs_free_extent(trans, root,
-                                        btrfs_file_extent_disk_blocknr(fi),
+                disk_blocknr = btrfs_file_extent_disk_blocknr(fi);
+                if (disk_blocknr == 0)
+                        continue;
+                ret = btrfs_free_extent(trans, root, disk_blocknr,
                                         btrfs_file_extent_disk_num_blocks(fi),
                                         0);
                 BUG_ON(ret);