fanotify: allow userspace to override max queue depth
fanotify has a defualt max queue depth. This patch allows processes which
explicitly request it to have an 'unlimited' queue depth. These processes
need to be very careful to make sure they cannot fall far enough behind
that they OOM the box. Thus this flag is gated on CAP_SYS_ADMIN.
Signed-off-by: Eric Paris <eparis@redhat.com>
diff --git a/include/linux/fanotify.h b/include/linux/fanotify.h
index ed479b6..e37f559 100644
--- a/include/linux/fanotify.h
+++ b/include/linux/fanotify.h
@@ -28,12 +28,13 @@
#define FAN_CLASS_NOTIF 0x00000000
#define FAN_CLASS_CONTENT 0x00000004
#define FAN_CLASS_PRE_CONTENT 0x00000008
-
#define FAN_ALL_CLASS_BITS (FAN_CLASS_NOTIF | FAN_CLASS_CONTENT | \
FAN_CLASS_PRE_CONTENT)
+#define FAN_UNLIMITED_QUEUE 0x00000010
+
#define FAN_ALL_INIT_FLAGS (FAN_CLOEXEC | FAN_NONBLOCK | \
- FAN_ALL_CLASS_BITS)
+ FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE)
/* flags used for fanotify_modify_mark() */
#define FAN_MARK_ADD 0x00000001