From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Date: Sun, 16 Nov 2008 16:05:39 +0000 (-0500)
Subject: ext4: Mark the buffer_heads as dirty and uptodate after prepare_write
X-Git-Tag: v2.6.27.8~8
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7cd10cb101e006e5beb4f3da3826727ed5ef85f8;p=thirdparty%2Fkernel%2Fstable.git

ext4: Mark the buffer_heads as dirty and uptodate after prepare_write

(cherry picked from commit ed9b3e3379731e9f9d2f73f3d7fd9e7d2ce3df4a)

We need to make sure we mark the buffer_heads as dirty and uptodate
so that block_write_full_page write them correctly.

This fixes mmap corruptions that can occur in low memory situations.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 4ec89d30d90ca..846a79096c257 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2242,6 +2242,8 @@ static int ext4_da_writepage(struct page *page,
 			unlock_page(page);
 			return 0;
 		}
+		/* now mark the buffer_heads as dirty and uptodate */
+		block_commit_write(page, 0, PAGE_CACHE_SIZE);
 	}
 
 	if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))