@@ -47,6 +47,22 @@ struct xattr_handler {
size_t size, int flags);
};
+/**
+ * xattr_handler_can_list - check whether xattr can be listed
+ * @handler: handler for this type of xattr
+ * @dentry: dentry whose inode xattr to list
+ *
+ * Determine whether the xattr associated with @dentry can be listed given
+ * @handler.
+ *
+ * Return: true if xattr can be listed, false if not.
+ */
+static inline bool xattr_handler_can_list(const struct xattr_handler *handler,
+ struct dentry *dentry)
+{
+ return handler && (!handler->list || handler->list(dentry));
+}
+
const char *xattr_full_name(const struct xattr_handler *, const char *);
struct xattr {
Add a tiny helper to determine whether an xattr handler given a specific dentry supports listing the requested xattr. We will use this helper in various filesystems in later commits. Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org> --- Changes in v2: - Remove second helper after architectural changes in the series. - Christoph Hellwig <hch@lst.de>: - Renamed helper to xattr_handler_can_list(). --- include/linux/xattr.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)