fanotify: permissions and blocking

This is the backend work needed for fanotify to support the new
FS_OPEN_PERM and FS_ACCESS_PERM fsnotify events.  This is done using the
new fsnotify secondary queue.  No userspace interface is provided actually
respond to or request these events.

Signed-off-by: Eric Paris <eparis@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index c34728e7d8cb..b0d00fd6bfad 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -160,6 +160,14 @@ struct fsnotify_group {
                         struct user_struct      *user;
                 } inotify_data;
 #endif
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+                struct fanotify_group_private_data {
+                        /* allows a group to block waiting for a userspace response */
+                        struct mutex access_mutex;
+                        struct list_head access_list;
+                        wait_queue_head_t access_waitq;
+                } fanotify_data;
+#endif
         };
 };
 
@@ -227,6 +235,10 @@ struct fsnotify_event {
         size_t name_len;
         struct pid *tgid;
 
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+        __u32 response; /* userspace answer to question */
+#endif /* CONFIG_FANOTIFY_ACCESS_PERMISSIONS */
+
         struct list_head private_data_list;     /* groups can store private data here */
 };