Commit Graph

304 Commits

Author SHA1 Message Date
Eric Paris
9dced01a09 fanotify: do not clone on merge unless needed
Currently if 2 events are going to be merged on the notication queue with
different masks the second event will be cloned and will replace the first
event.  However if this notification queue is the only place referencing
the event in question there is no reason not to just update the event in
place.  We can tell this if the event->refcnt == 1.  Since we hold a
reference for each queue this event is on we know that when refcnt == 1
this is the only queue.  The other concern is that it might be about to be
added to a new queue, but this can't be the case since fsnotify holds a
reference on the event until it is finished adding it to queues.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:55 -04:00
Eric Paris
a12a7dd328 fanotify: merge notification events with different masks
Instead of just merging fanotify events if they are exactly the same, merge
notification events with different masks.  To do this we have to clone the
old event, update the mask in the new event with the new merged mask, and
put the new event in place of the old event.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:55 -04:00
Eric Paris
767cd46c33 fanotify:drop notification if they exist in the outgoing queue
fanotify listeners get an open file descriptor to the object in question so
the ordering of operations is not as important as in other notification
systems.  inotify will drop events if the last event in the event FIFO is
the same as the current event.  This patch will drop fanotify events if
they are the same as another event anywhere in the event FIFO.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:54 -04:00
Eric Paris
ff0b16a985 fanotify: fscking all notification system
fanotify is a novel file notification system which bases notification on
giving userspace both an event type (open, close, read, write) and an open
file descriptor to the object in question.  This should address a number of
races and problems with other notification systems like inotify and dnotify
and should allow the future implementation of blocking or access controlled
notification.  These are useful for on access scanners or hierachical storage
management schemes.

This patch just implements the basics of the fsnotify functions.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:54 -04:00