From: Theodore Ts'o <tytso@mit.edu>
Date: Tue, 9 Jun 2009 13:54:40 +0000 (-0400)
Subject: ext4: Don't treat a truncation of a zero-length file as replace-via-truncate
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0eab928221bac8895a0b494a16a8810002bd8645;p=linux-beck.git

ext4: Don't treat a truncation of a zero-length file as replace-via-truncate

If a non-existent file is opened via O_WRONLY|O_CREAT|O_TRUNC, there's
no need to treat this as a true file truncation, so we shouldn't
activate the replace-via-truncate hueristic.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 2c10d346f7a3..875db944b22f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4127,7 +4127,8 @@ void ext4_truncate(struct inode *inode)
 	if (!ext4_can_truncate(inode))
 		return;
 
-	if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
+	if (ei->i_disksize && inode->i_size == 0 &&
+	    !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
 		ei->i_state |= EXT4_STATE_DA_ALLOC_CLOSE;
 
 	if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL) {