vfs: vfs_dedupe_file_range() doesn't return EOPNOTSUPP

It returns EINVAL when the operation is not supported by the
filesystem. Fix it to return EOPNOTSUPP to be consistent with
the man page and clone_file_range().

Clean up the inconsistent error return handling while I'm there.
(I know, lipstick on a pig, but every little bit helps...)

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/read_write.c b/fs/read_write.c
index bfcb4ce..4dae039 100644 (file)
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -2094,17 +2094,18 @@ int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
        off = same->src_offset;
        len = same->src_length;
 
-       ret = -EISDIR;
        if (S_ISDIR(src->i_mode))
-               goto out;
+               return -EISDIR;
 
-       ret = -EINVAL;
        if (!S_ISREG(src->i_mode))
-               goto out;
+               return -EINVAL;
+
+       if (!file->f_op->remap_file_range)
+               return -EOPNOTSUPP;
 
        ret = remap_verify_area(file, off, len, false);
        if (ret < 0)
-               goto out;
+               return ret;
        ret = 0;
 
        if (off + len > i_size_read(src))
@@ -2147,10 +2148,8 @@ next_fdput:
                fdput(dst_fd);
 next_loop:
                if (fatal_signal_pending(current))
-                       goto out;
+                       break;
        }
-
-out:
        return ret;
 }
 EXPORT_SYMBOL(vfs_dedupe_file_range);