1 files changed, 31 insertions, 19 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 9879bd474632..b232150b5b6b 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3797,16 +3797,16 @@ void btrfs_free_block_rsv(struct btrfs_root *root,
 	kfree(rsv);
 }
 
-int btrfs_block_rsv_add(struct btrfs_root *root,
-			struct btrfs_block_rsv *block_rsv,
-			u64 num_bytes)
+static inline int __block_rsv_add(struct btrfs_root *root,
+				  struct btrfs_block_rsv *block_rsv,
+				  u64 num_bytes, int flush)
 {
 	int ret;
 
 	if (num_bytes == 0)
 		return 0;
 
-	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, 1);
+	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
 	if (!ret) {
 		block_rsv_add_bytes(block_rsv, num_bytes, 1);
 		return 0;
@@ -3815,22 +3815,18 @@ int btrfs_block_rsv_add(struct btrfs_root *root,
 	return ret;
 }
 
+int btrfs_block_rsv_add(struct btrfs_root *root,
+			struct btrfs_block_rsv *block_rsv,
+			u64 num_bytes)
+{
+	return __block_rsv_add(root, block_rsv, num_bytes, 1);
+}
+
 int btrfs_block_rsv_add_noflush(struct btrfs_root *root,
 				struct btrfs_block_rsv *block_rsv,
 				u64 num_bytes)
 {
-	int ret;
-
-	if (num_bytes == 0)
-		return 0;
-
-	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, 0);
-	if (!ret) {
-		block_rsv_add_bytes(block_rsv, num_bytes, 1);
-		return 0;
-	}
-
-	return ret;
+	return __block_rsv_add(root, block_rsv, num_bytes, 0);
 }
 
 int btrfs_block_rsv_check(struct btrfs_root *root,
@@ -4064,23 +4060,30 @@ int btrfs_snap_reserve_metadata(struct btrfs_trans_handle *trans,
  */
 static unsigned drop_outstanding_extent(struct inode *inode)
 {
+	unsigned drop_inode_space = 0;
 	unsigned dropped_extents = 0;
 
 	BUG_ON(!BTRFS_I(inode)->outstanding_extents);
 	BTRFS_I(inode)->outstanding_extents--;
 
+	if (BTRFS_I(inode)->outstanding_extents == 0 &&
+	    BTRFS_I(inode)->delalloc_meta_reserved) {
+		drop_inode_space = 1;
+		BTRFS_I(inode)->delalloc_meta_reserved = 0;
+	}
+
 	/*
 	 * If we have more or the same amount of outsanding extents than we have
 	 * reserved then we need to leave the reserved extents count alone.
 	 */
 	if (BTRFS_I(inode)->outstanding_extents >=
 	    BTRFS_I(inode)->reserved_extents)
-		return 0;
+		return drop_inode_space;
 
 	dropped_extents = BTRFS_I(inode)->reserved_extents -
 		BTRFS_I(inode)->outstanding_extents;
 	BTRFS_I(inode)->reserved_extents -= dropped_extents;
-	return dropped_extents;
+	return dropped_extents + drop_inode_space;
 }
 
 /**
@@ -4166,9 +4169,18 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 		nr_extents = BTRFS_I(inode)->outstanding_extents -
 			BTRFS_I(inode)->reserved_extents;
 		BTRFS_I(inode)->reserved_extents += nr_extents;
+	}
 
-		to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
+	/*
+	 * Add an item to reserve for updating the inode when we complete the
+	 * delalloc io.
+	 */
+	if (!BTRFS_I(inode)->delalloc_meta_reserved) {
+		nr_extents++;
+		BTRFS_I(inode)->delalloc_meta_reserved = 1;
 	}
+
+	to_reserve = btrfs_calc_trans_metadata_size(root, nr_extents);
 	to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
 	spin_unlock(&BTRFS_I(inode)->lock);