dm: uevent generate events
This patch adds support for the dm_path_event dm_send_event functions which
create and send udev events.
Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index bb5c1ea..07cbbb8 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -113,6 +113,9 @@
*/
atomic_t event_nr;
wait_queue_head_t eventq;
+ atomic_t uevent_seq;
+ struct list_head uevent_list;
+ spinlock_t uevent_lock; /* Protect access to uevent_list */
/*
* freeze/thaw support require holding onto a super block
@@ -985,6 +988,9 @@
atomic_set(&md->holders, 1);
atomic_set(&md->open_count, 0);
atomic_set(&md->event_nr, 0);
+ atomic_set(&md->uevent_seq, 0);
+ INIT_LIST_HEAD(&md->uevent_list);
+ spin_lock_init(&md->uevent_lock);
md->queue = blk_alloc_queue(GFP_KERNEL);
if (!md->queue)
@@ -1083,8 +1089,16 @@
*/
static void event_callback(void *context)
{
+ unsigned long flags;
+ LIST_HEAD(uevents);
struct mapped_device *md = (struct mapped_device *) context;
+ spin_lock_irqsave(&md->uevent_lock, flags);
+ list_splice_init(&md->uevent_list, &uevents);
+ spin_unlock_irqrestore(&md->uevent_lock, flags);
+
+ dm_send_uevents(&uevents, &md->disk->kobj);
+
atomic_inc(&md->event_nr);
wake_up(&md->eventq);
}
@@ -1502,6 +1516,11 @@
/*-----------------------------------------------------------------
* Event notification.
*---------------------------------------------------------------*/
+uint32_t dm_next_uevent_seq(struct mapped_device *md)
+{
+ return atomic_add_return(1, &md->uevent_seq);
+}
+
uint32_t dm_get_event_nr(struct mapped_device *md)
{
return atomic_read(&md->event_nr);
@@ -1513,6 +1532,15 @@
(event_nr != atomic_read(&md->event_nr)));
}
+void dm_uevent_add(struct mapped_device *md, struct list_head *elist)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&md->uevent_lock, flags);
+ list_add(elist, &md->uevent_list);
+ spin_unlock_irqrestore(&md->uevent_lock, flags);
+}
+
/*
* The gendisk is only valid as long as you have a reference
* count on 'md'.