From: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Date: Sun, 19 Oct 2008 03:28:00 +0000 (-0700)
Subject: ext3: truncate block allocated on a failed ext3_write_begin
X-Git-Tag: v2.6.28-rc1~158
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=5ec8b75e3a2a94860ee99b5456fe1a963c8680e5;p=linux-2.6-omap-h63xx.git

ext3: truncate block allocated on a failed ext3_write_begin

For blocksize < pagesize we need to remove blocks that got allocated in
block_write_begin() if we fail with ENOSPC for later blocks.
block_write_begin() internally does this if it allocated page locally.
This makes sure we don't have blocks outside inode.i_size during ENOSPC.

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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index ebfec4d0148..f8424ad8997 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1186,6 +1186,13 @@ write_begin_failed:
 		ext3_journal_stop(handle);
 		unlock_page(page);
 		page_cache_release(page);
+		/*
+		 * block_write_begin may have instantiated a few blocks
+		 * outside i_size.  Trim these off again. Don't need
+		 * i_size_read because we hold i_mutex.
+		 */
+		if (pos + len > inode->i_size)
+			vmtruncate(inode, inode->i_size);
 	}
 	if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries))
 		goto retry;