From: Jaegeuk Kim <jaegeuk@kernel.org>
Date: Thu, 26 Feb 2015 03:54:48 +0000 (-0800)
Subject: f2fs: check its block allocation to avoid producing wrong dirty pages
X-Git-Tag: v4.1-rc1~87^2~47
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=b7f204cca4b7155f47e64555614b1f534a53737e;p=karo-tx-linux.git

f2fs: check its block allocation to avoid producing wrong dirty pages

If a page is cached but its block was deallocated, we don't need to make
the page dirty again by gc and truncate_partial_data_page.

In that case, it needs to check its block allocation all the time instead
of giving up-to-date page.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 62e31b2aa131..389fda772e69 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -813,11 +813,19 @@ struct page *find_data_page(struct inode *inode, pgoff_t index, bool sync)
 		.rw = sync ? READ_SYNC : READA,
 	};
 
+	/*
+	 * If sync is false, it needs to check its block allocation.
+	 * This is need and triggered by two flows:
+	 *   gc and truncate_partial_data_page.
+	 */
+	if (!sync)
+		goto search;
+
 	page = find_get_page(mapping, index);
 	if (page && PageUptodate(page))
 		return page;
 	f2fs_put_page(page, 0);
-
+search:
 	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 		dn.data_blkaddr = ei.blk + index - ei.fofs;
 		goto got_it;