f2fs: handle readonly filesystem in f2fs_ioc_shutdown()

[ Upstream commit 8626441f05dc45a2f4693ee6863d02456ce39e60 ]

If mountpoint is readonly, we should allow shutdowning filesystem
successfully, this fixes issue found by generic/599 testcase of
xfstest.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index c3a9da7..5d94abe 100644 (file)
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2056,8 +2056,15 @@ static int f2fs_ioc_shutdown(struct file *filp, unsigned long arg)
 
        if (in != F2FS_GOING_DOWN_FULLSYNC) {
                ret = mnt_want_write_file(filp);
-               if (ret)
+               if (ret) {
+                       if (ret == -EROFS) {
+                               ret = 0;
+                               f2fs_stop_checkpoint(sbi, false);
+                               set_sbi_flag(sbi, SBI_IS_SHUTDOWN);
+                               trace_f2fs_shutdown(sbi, in, ret);
+                       }
                        return ret;
+               }
        }
 
        switch (in) {