1 files changed, 42 insertions, 0 deletions

diff --git a/fs/open.c b/fs/open.c
index 1540632d8387..13bece4f36a4 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -811,6 +811,48 @@ out_err:
 EXPORT_SYMBOL_GPL(lookup_instantiate_filp);
 
 /**
+ * finish_open - finish opening a file
+ * @od: opaque open data
+ * @dentry: pointer to dentry
+ * @open: open callback
+ *
+ * This can be used to finish opening a file passed to i_op->atomic_open().
+ *
+ * If the open callback is set to NULL, then the standard f_op->open()
+ * filesystem callback is substituted.
+ */
+struct file *finish_open(struct opendata *od, struct dentry *dentry,
+                         int (*open)(struct inode *, struct file *))
+{
+        struct file *res;
+
+        mntget(od->mnt);
+        dget(dentry);
+
+        res = do_dentry_open(dentry, od->mnt, *od->filp, open, current_cred());
+        if (!IS_ERR(res))
+                *od->filp = NULL;
+
+        return res;
+}
+EXPORT_SYMBOL(finish_open);
+
+/**
+ * finish_no_open - finish ->atomic_open() without opening the file
+ *
+ * @od: opaque open data
+ * @dentry: dentry or NULL (as returned from ->lookup())
+ *
+ * This can be used to set the result of a successful lookup in ->atomic_open().
+ * The filesystem's atomic_open() method shall return NULL after calling this.
+ */
+void finish_no_open(struct opendata *od, struct dentry *dentry)
+{
+        od->dentry = dentry;
+}
+EXPORT_SYMBOL(finish_no_open);
+
+/**
  * nameidata_to_filp - convert a nameidata to an open filp.
  * @nd: pointer to nameidata
  * @flags: open flags