From: Jan Kara <jack@suse.cz>
Date: Mon, 10 Jan 2011 17:30:39 +0000 (-0500)
Subject: ext4: fix trimming of a single group
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=ca6e909f9bebe709bc65a3ee605ce32969db0452;p=linux-beck.git

ext4: fix trimming of a single group

When ext4_trim_fs() is called to trim a part of a single group, the
logic will wrongly set last block of the interval to 'len' instead
of 'first_block + len'. Thus a shorter interval is possibly trimmed.
Fix it.

CC: Lukas Czerner <lczerner@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index d47a80ec231d..21ee30b86de5 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4860,7 +4860,7 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
 		if (len >= EXT4_BLOCKS_PER_GROUP(sb))
 			len -= (EXT4_BLOCKS_PER_GROUP(sb) - first_block);
 		else
-			last_block = len;
+			last_block = first_block + len;
 
 		if (e4b.bd_info->bb_free >= minlen) {
 			cnt = ext4_trim_all_free(sb, &e4b, first_block,