vfs: no mnt_want_write_file() in vfs_{copy,clone}_file_range()

We've checked for file_out being opened for write.  This ensures that we
already have mnt_want_write() on target.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/read_write.c b/fs/read_write.c
index 190e0d3..3d810a1 100644 (file)
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1538,9 +1538,7 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
        if (len == 0)
                return 0;
 
-       ret = mnt_want_write_file(file_out);
-       if (ret)
-               return ret;
+       sb_start_write(inode_out->i_sb);
 
        ret = -EOPNOTSUPP;
        if (file_out->f_op->copy_file_range)
@@ -1559,7 +1557,7 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
        inc_syscr(current);
        inc_syscw(current);
 
-       mnt_drop_write_file(file_out);
+       sb_end_write(inode_out->i_sb);
 
        return ret;
 }
@@ -1685,9 +1683,7 @@ int vfs_clone_file_range(struct file *file_in, loff_t pos_in,
        if (pos_in + len > i_size_read(inode_in))
                return -EINVAL;
 
-       ret = mnt_want_write_file(file_out);
-       if (ret)
-               return ret;
+       sb_start_write(inode_out->i_sb);
 
        ret = file_in->f_op->clone_file_range(file_in, pos_in,
                        file_out, pos_out, len);
@@ -1696,7 +1692,7 @@ int vfs_clone_file_range(struct file *file_in, loff_t pos_in,
                fsnotify_modify(file_out);
        }
 
-       mnt_drop_write_file(file_out);
+       sb_end_write(inode_out->i_sb);
        return ret;
 }
 EXPORT_SYMBOL(vfs_clone_file_range);