f2fs: prevent atomic write on pinned file

Since atomic write way was changed to out-place-update, we should
prevent it on pinned files.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/file.c

@@ -2083,7 +2083,8 @@ static int f2fs_ioc_start_atomic_write(struct file *filp, bool truncate)
 
 	inode_lock(inode);
 
-	if (!f2fs_disable_compressed_file(inode)) {
+	if (!f2fs_disable_compressed_file(inode) ||
+			f2fs_is_pinned_file(inode)) {
 		ret = -EINVAL;
 		goto out;
 	}