Merge branch 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs fixes from Chris Mason:
 "A few more btrfs fixes.

  These range from corners Filipe found in the new free space cache
  writeback to a grab bag of fixes from the list"

* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: btrfs_release_extent_buffer_page didn't free pages of dummy extent
  Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.
  btrfs: unlock i_mutex after attempting to delete subvolume during send
  btrfs: check io_ctl_prepare_pages return in __btrfs_write_out_cache
  btrfs: fix race on ENOMEM in alloc_extent_buffer
  btrfs: handle ENOMEM in btrfs_alloc_tree_block
  Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole
  Btrfs: don't check for delalloc_bytes in cache_save_setup
  Btrfs: fix deadlock when starting writeback of bg caches
  Btrfs: fix race between start dirty bg cache writeout and bg deletion

1 files changed, 11 insertions, 4 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 8bcd2a007517..96aebf3bcd5b 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1058,6 +1058,7 @@ static int contains_pending_extent(struct btrfs_trans_handle *trans,
 	struct extent_map *em;
 	struct list_head *search_list = &trans->transaction->pending_chunks;
 	int ret = 0;
+	u64 physical_start = *start;
 
 again:
 	list_for_each_entry(em, search_list, list) {
@@ -1068,9 +1069,9 @@ again:
 		for (i = 0; i < map->num_stripes; i++) {
 			if (map->stripes[i].dev != device)
 				continue;
-			if (map->stripes[i].physical >= *start + len ||
+			if (map->stripes[i].physical >= physical_start + len ||
 			    map->stripes[i].physical + em->orig_block_len <=
-			    *start)
+			    physical_start)
 				continue;
 			*start = map->stripes[i].physical +
 				em->orig_block_len;
@@ -1193,8 +1194,14 @@ again:
 			 */
 			if (contains_pending_extent(trans, device,
 						    &search_start,
-						    hole_size))
-				hole_size = 0;
+						    hole_size)) {
+				if (key.offset >= search_start) {
+					hole_size = key.offset - search_start;
+				} else {
+					WARN_ON_ONCE(1);
+					hole_size = 0;
+				}
+			}
 
 			if (hole_size > max_hole_size) {
 				max_hole_start = search_start;