From 5710911ece194655aa4379bb76c7f3f9827f174b Mon Sep 17 00:00:00 2001
From: Liu Bo <bo.li.liu@oracle.com>
Date: Wed, 22 Aug 2012 20:10:38 -0600
Subject: [PATCH] --- yaml --- r: 322372 b: refs/heads/master c:
 24c03fa5cf3d02c327cf9f2fc39f72664b1bd7e1 h: refs/heads/master v: v3

---
 [refs]                 |  2 +-
 trunk/fs/btrfs/inode.c | 24 ++++++++++++++++++++----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/[refs] b/[refs]
index c4599f5fd288..1a6377ffc726 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: bd7de2c9a449e26a5493d918618eb20ae60d56bd
+refs/heads/master: 24c03fa5cf3d02c327cf9f2fc39f72664b1bd7e1
diff --git a/trunk/fs/btrfs/inode.c b/trunk/fs/btrfs/inode.c
index 0808f483dafa..38cda78de5e4 100644
--- a/trunk/fs/btrfs/inode.c
+++ b/trunk/fs/btrfs/inode.c
@@ -5992,11 +5992,27 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
 	 * in the case of read we need to unlock only the end area that we
 	 * aren't using if there is any left over space.
 	 */
-	if (lockstart < lockend)
-		clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
-				 unlock_bits, 1, 0, &cached_state, GFP_NOFS);
-	else
+	if (lockstart < lockend) {
+		if (create && len < lockend - lockstart) {
+			clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
+					 lockstart + len - 1, unlock_bits, 1, 0,
+					 &cached_state, GFP_NOFS);
+			/*
+			 * Beside unlock, we also need to cleanup reserved space
+			 * for the left range by attaching EXTENT_DO_ACCOUNTING.
+			 */
+			clear_extent_bit(&BTRFS_I(inode)->io_tree,
+					 lockstart + len, lockend,
+					 unlock_bits | EXTENT_DO_ACCOUNTING,
+					 1, 0, NULL, GFP_NOFS);
+		} else {
+			clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart,
+					 lockend, unlock_bits, 1, 0,
+					 &cached_state, GFP_NOFS);
+		}
+	} else {
 		free_extent_state(cached_state);
+	}
 
 	free_extent_map(em);