From 81e68e5e85e5fec0d781245d3116d4b1224ccca9 Mon Sep 17 00:00:00 2001
From: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Date: Mon, 5 Jan 2009 22:38:48 -0500
Subject: [PATCH] --- yaml --- r: 127963 b: refs/heads/master c:
 c39a7f84d7845aa95d1c7c168f38215aedcc13c2 h: refs/heads/master i:   127961:
 f05f3273ba7bef82f315003fd740df7899b2cd44   127959:
 8037cbd3081450a8856f2f47bae872035cb2d96f v: v3

---
 [refs]                |  2 +-
 trunk/fs/ext4/super.c | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index deaa4c032ca4..2d29d21e6e48 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6b082b531228c43d454c082fc0f969da1695b060
+refs/heads/master: c39a7f84d7845aa95d1c7c168f38215aedcc13c2
diff --git a/trunk/fs/ext4/super.c b/trunk/fs/ext4/super.c
index a3321bf22311..e5ab520724da 100644
--- a/trunk/fs/ext4/super.c
+++ b/trunk/fs/ext4/super.c
@@ -907,6 +907,25 @@ static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
 				    ext4_nfs_get_inode);
 }
 
+/*
+ * Try to release metadata pages (indirect blocks, directories) which are
+ * mapped via the block device.  Since these pages could have journal heads
+ * which would prevent try_to_free_buffers() from freeing them, we must use
+ * jbd2 layer's try_to_free_buffers() function to release them.
+ */
+static int bdev_try_to_free_page(struct super_block *sb, struct page *page, gfp_t wait)
+{
+	journal_t *journal = EXT4_SB(sb)->s_journal;
+
+	WARN_ON(PageChecked(page));
+	if (!page_has_buffers(page))
+		return 0;
+	if (journal)
+		return jbd2_journal_try_to_free_buffers(journal, page,
+							wait & ~__GFP_WAIT);
+	return try_to_free_buffers(page);
+}
+
 #ifdef CONFIG_QUOTA
 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
@@ -971,6 +990,7 @@ static const struct super_operations ext4_sops = {
 	.quota_read	= ext4_quota_read,
 	.quota_write	= ext4_quota_write,
 #endif
+	.bdev_try_to_free_page = bdev_try_to_free_page,
 };
 
 static const struct export_operations ext4_export_ops = {