From b1c770c273a4787069306fc82aab245e9ac72e9d Mon Sep 17 00:00:00 2001
From: Dave Chinner <dchinner@redhat.com>
Date: Wed, 21 Dec 2011 00:07:42 +0000
Subject: [PATCH] xfs: fix endian conversion issue in discard code

When finding the longest extent in an AG, we read the value directly
out of the AGF buffer without endian conversion. This will give an
incorrect length, resulting in FITRIM operations potentially not
trimming everything that it should.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
---
 fs/xfs/xfs_discard.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c
index 8a24f0c6c860..286a051f12cf 100644
--- a/fs/xfs/xfs_discard.c
+++ b/fs/xfs/xfs_discard.c
@@ -68,7 +68,7 @@ xfs_trim_extents(
 	 * Look up the longest btree in the AGF and start with it.
 	 */
 	error = xfs_alloc_lookup_le(cur, 0,
-				    XFS_BUF_TO_AGF(agbp)->agf_longest, &i);
+			    be32_to_cpu(XFS_BUF_TO_AGF(agbp)->agf_longest), &i);
 	if (error)
 		goto out_del_cursor;
 
@@ -84,7 +84,7 @@ xfs_trim_extents(
 		if (error)
 			goto out_del_cursor;
 		XFS_WANT_CORRUPTED_GOTO(i == 1, out_del_cursor);
-		ASSERT(flen <= XFS_BUF_TO_AGF(agbp)->agf_longest);
+		ASSERT(flen <= be32_to_cpu(XFS_BUF_TO_AGF(agbp)->agf_longest));
 
 		/*
 		 * Too small?  Give up.
-- 
2.34.1