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From:   Vasily Averin <vvs@virtuozzo.com>
Subject: [PATCH] fuse_writepages ignores errors from fuse_writepages_fill
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     linux-fsdevel@vger.kernel.org, Maxim Patlasov <maximvp@gmail.com>,
        Kirill Tkhai <ktkhai@virtuozzo.com>,
        LKML <linux-kernel@vger.kernel.org>
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fuse_writepages() ignores some errors taken from fuse_writepages_fill()
I believe it is a bug: if .writepages is called with WB_SYNC_ALL
it should either guarantee that all data was successfully saved
or return error.

Fixes: 26d614df1da9 ("fuse: Implement writepages callback")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
---
 fs/fuse/file.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index c023f7f0..5986739 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -2148,10 +2148,8 @@ static int fuse_writepages(struct address_space *mapping,
 
 	err = write_cache_pages(mapping, wbc, fuse_writepages_fill, &data);
 	if (data.wpa) {
-		/* Ignore errors if we can write at least one page */
 		WARN_ON(!data.wpa->ia.ap.num_pages);
 		fuse_writepages_send(&data);
-		err = 0;
 	}
 	if (data.ff)
 		fuse_file_put(data.ff, false, false);
-- 
1.8.3.1