f2fs: allow direct read for zoned device

This reverts dbf8e63f48af ("f2fs: remove device type check for direct IO"),
and apply the below first version, since it contributed out-of-order DIO writes.

For zoned devices, f2fs forbids direct IO and forces buffered IO
to serialize write IOs. However, the constraint does not apply to
read IOs.

Cc: stable@vger.kernel.org
Fixes: dbf8e63f48af ("f2fs: remove device type check for direct IO")
Signed-off-by: Eunhee Rho <eunhee83.rho@samsung.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b63b482c35a8549f4c34d58e8117fce2c3eacb43..1ebc08be958ebee0c297360cacddcb917afc43b4 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -4526,7 +4526,12 @@ static inline bool f2fs_force_buffered_io(struct inode *inode,
        /* disallow direct IO if any of devices has unaligned blksize */
        if (f2fs_is_multi_device(sbi) && !sbi->aligned_blksize)
                return true;
-
+       /*
+        * for blkzoned device, fallback direct IO to buffered IO, so
+        * all IOs can be serialized by log-structured write.
+        */
+       if (f2fs_sb_has_blkzoned(sbi) && (rw == WRITE))
+               return true;
        if (f2fs_lfs_mode(sbi) && (rw == WRITE)) {
                if (block_unaligned_IO(inode, iocb, iter))
                        return true;