Merge branch 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue fix from Tejun Heo:
 "This pull request contains a workqueue usage fix for firewire.

  For quite a long time now, workqueue only treats two work items
  identical iff both their addresses and callbacks match.  This is to
  avoid introducing false dependency through the work item being
  recycled while being executed.  This changes non-reentrancy guarantee
  for the users of PREPARE[_DELAYED]_WORK() - if the function changes,
  reentrancy isn't guaranteed against the previous instance.  Firewire
  depended on such nonreentrancy guarantee.

  This is fixed by doing the work item multiplexing from firewire proper
  while keeping the work function unchanged"

* 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  firewire: don't use PREPARE_DELAYED_WORK

1 files changed, 13 insertions, 4 deletions

diff --git a/drivers/firewire/sbp2.c b/drivers/firewire/sbp2.c
index 281029daf98c..7aef911fdc71 100644
--- a/drivers/firewire/sbp2.c
+++ b/drivers/firewire/sbp2.c
@@ -146,6 +146,7 @@ struct sbp2_logical_unit {
 	 */
 	int generation;
 	int retries;
+	work_func_t workfn;
 	struct delayed_work work;
 	bool has_sdev;
 	bool blocked;
@@ -864,7 +865,7 @@ static void sbp2_login(struct work_struct *work)
 	/* set appropriate retry limit(s) in BUSY_TIMEOUT register */
 	sbp2_set_busy_timeout(lu);
 
-	PREPARE_DELAYED_WORK(&lu->work, sbp2_reconnect);
+	lu->workfn = sbp2_reconnect;
 	sbp2_agent_reset(lu);
 
 	/* This was a re-login. */
@@ -918,7 +919,7 @@ static void sbp2_login(struct work_struct *work)
 	 * If a bus reset happened, sbp2_update will have requeued
 	 * lu->work already.  Reset the work from reconnect to login.
 	 */
-	PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
+	lu->workfn = sbp2_login;
 }
 
 static void sbp2_reconnect(struct work_struct *work)
@@ -952,7 +953,7 @@ static void sbp2_reconnect(struct work_struct *work)
 		    lu->retries++ >= 5) {
 			dev_err(tgt_dev(tgt), "failed to reconnect\n");
 			lu->retries = 0;
-			PREPARE_DELAYED_WORK(&lu->work, sbp2_login);
+			lu->workfn = sbp2_login;
 		}
 		sbp2_queue_work(lu, DIV_ROUND_UP(HZ, 5));
 
@@ -972,6 +973,13 @@ static void sbp2_reconnect(struct work_struct *work)
 	sbp2_conditionally_unblock(lu);
 }
 
+static void sbp2_lu_workfn(struct work_struct *work)
+{
+	struct sbp2_logical_unit *lu = container_of(to_delayed_work(work),
+						struct sbp2_logical_unit, work);
+	lu->workfn(work);
+}
+
 static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 {
 	struct sbp2_logical_unit *lu;
@@ -998,7 +1006,8 @@ static int sbp2_add_logical_unit(struct sbp2_target *tgt, int lun_entry)
 	lu->blocked  = false;
 	++tgt->dont_block;
 	INIT_LIST_HEAD(&lu->orb_list);
-	INIT_DELAYED_WORK(&lu->work, sbp2_login);
+	lu->workfn = sbp2_login;
+	INIT_DELAYED_WORK(&lu->work, sbp2_lu_workfn);
 
 	list_add_tail(&lu->link, &tgt->lu_list);
 	return 0;