From: Vasily Averin <vvs@virtuozzo.com>
Date: Thu, 25 Jun 2020 12:39:51 +0300
Subject: fuse: don't ignore errors from fuse_writepages_fill()
Git-commit: 7779b047a57f6824a43d0e1f70de2741b7426b9d
Patch-mainline: v5.8-rc6
References: bsc#1177193

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>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 fs/fuse/file.c |    2 --
 1 file changed, 2 deletions(-)

--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -2010,10 +2010,8 @@ static int fuse_writepages(struct addres
 
 	err = write_cache_pages(mapping, wbc, fuse_writepages_fill, &data);
 	if (data.req) {
-		/* Ignore errors if we can write at least one page */
 		BUG_ON(!data.req->num_pages);
 		fuse_writepages_send(&data);
-		err = 0;
 	}
 	if (data.ff)
 		fuse_file_put(data.ff, false, false);