overlay: Call ovl_drop_write() earlier in ovl_dentry_open()

Call ovl_drop_write() earlier in ovl_dentry_open() before we call vfs_open()
as we've done the copy up for which we needed the freeze-write lock by that
point.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 308379b..21079d1 100644 (file)
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -343,31 +343,25 @@ static int ovl_dentry_open(struct dentry *dentry, struct file *file,
        int err;
        struct path realpath;
        enum ovl_path_type type;
-       bool want_write = false;
 
        type = ovl_path_real(dentry, &realpath);
        if (ovl_open_need_copy_up(file->f_flags, type, realpath.dentry)) {
-               want_write = true;
                err = ovl_want_write(dentry);
                if (err)
-                       goto out;
+                       return err;
 
                if (file->f_flags & O_TRUNC)
                        err = ovl_copy_up_last(dentry, NULL, true);
                else
                        err = ovl_copy_up(dentry);
+               ovl_drop_write(dentry);
                if (err)
-                       goto out_drop_write;
+                       return err;
 
                ovl_path_upper(dentry, &realpath);
        }
 
-       err = vfs_open(&realpath, file, cred);
-out_drop_write:
-       if (want_write)
-               ovl_drop_write(dentry);
-out:
-       return err;
+       return vfs_open(&realpath, file, cred);
 }
 
 static const struct inode_operations ovl_file_inode_operations = {