From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Date: Mon, 28 Apr 2008 09:16:28 +0000 (-0700)
Subject: Add balance_dirty_pages_ratelimited() to cont_expand_zero()
X-Git-Tag: v2.6.26-rc1~725
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=061e97469f46f924cf14bbf1dd4805b46986691a;p=linux-2.6

Add balance_dirty_pages_ratelimited() to cont_expand_zero()

On the systems, ftruncate() which expand size for FAT became the cause
of OOM.  The cont_expand_zero() filled all memory with dirty pages,
and since disk is very slow, limit of page scanning was exceeded, then
it triggered OOM.

This adds balance_dirty_pages_ratelimited() to avoid filling memory
with dirty pages.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/buffer.c b/fs/buffer.c
index 7d51e649b1..3db4a26adc 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2246,6 +2246,8 @@ int cont_expand_zero(struct file *file, struct address_space *mapping,
 			goto out;
 		BUG_ON(err != len);
 		err = 0;
+
+		balance_dirty_pages_ratelimited(mapping);
 	}
 
 	/* page covers the boundary, find the boundary offset */