Merge branch 'akpm' (patchbomb from Andrew)

Merge first patchbomb from Andrew Morton:
 - a few minor cifs fixes
 - dma-debug upadtes
 - ocfs2
 - slab
 - about half of MM
 - procfs
 - kernel/exit.c
 - panic.c tweaks
 - printk upates
 - lib/ updates
 - checkpatch updates
 - fs/binfmt updates
 - the drivers/rtc tree
 - nilfs
 - kmod fixes
 - more kernel/exit.c
 - various other misc tweaks and fixes

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits)
  exit: pidns: fix/update the comments in zap_pid_ns_processes()
  exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting
  exit: exit_notify: re-use "dead" list to autoreap current
  exit: reparent: call forget_original_parent() under tasklist_lock
  exit: reparent: avoid find_new_reaper() if no children
  exit: reparent: introduce find_alive_thread()
  exit: reparent: introduce find_child_reaper()
  exit: reparent: document the ->has_child_subreaper checks
  exit: reparent: s/while_each_thread/for_each_thread/ in find_new_reaper()
  exit: reparent: fix the cross-namespace PR_SET_CHILD_SUBREAPER reparenting
  exit: reparent: fix the dead-parent PR_SET_CHILD_SUBREAPER reparenting
  exit: proc: don't try to flush /proc/tgid/task/tgid
  exit: release_task: fix the comment about group leader accounting
  exit: wait: drop tasklist_lock before psig->c* accounting
  exit: wait: don't use zombie->real_parent
  exit: wait: cleanup the ptrace_reparented() checks
  usermodehelper: kill the kmod_thread_locker logic
  usermodehelper: don't use CLONE_VFORK for ____call_usermodehelper()
  fs/hfs/catalog.c: fix comparison bug in hfs_cat_keycmp
  nilfs2: fix the nilfs_iget() vs. nilfs_new_inode() races
  ...

1 files changed, 31 insertions, 6 deletions

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 37297c14f9a3..1c423af04c69 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -861,8 +861,13 @@ static inline void ocfs2_generic_handle_convert_action(struct ocfs2_lock_res *lo
 	 * We set the OCFS2_LOCK_UPCONVERT_FINISHING flag before clearing
 	 * the OCFS2_LOCK_BUSY flag to prevent the dc thread from
 	 * downconverting the lock before the upconvert has fully completed.
+	 * Do not prevent the dc thread from downconverting if NONBLOCK lock
+	 * had already returned.
 	 */
-	lockres_or_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING);
+	if (!(lockres->l_flags & OCFS2_LOCK_NONBLOCK_FINISHED))
+		lockres_or_flags(lockres, OCFS2_LOCK_UPCONVERT_FINISHING);
+	else
+		lockres_clear_flags(lockres, OCFS2_LOCK_NONBLOCK_FINISHED);
 
 	lockres_clear_flags(lockres, OCFS2_LOCK_BUSY);
 }
@@ -1324,13 +1329,12 @@ static void lockres_add_mask_waiter(struct ocfs2_lock_res *lockres,
 
 /* returns 0 if the mw that was removed was already satisfied, -EBUSY
  * if the mask still hadn't reached its goal */
-static int lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
+static int __lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
 				      struct ocfs2_mask_waiter *mw)
 {
-	unsigned long flags;
 	int ret = 0;
 
-	spin_lock_irqsave(&lockres->l_lock, flags);
+	assert_spin_locked(&lockres->l_lock);
 	if (!list_empty(&mw->mw_item)) {
 		if ((lockres->l_flags & mw->mw_mask) != mw->mw_goal)
 			ret = -EBUSY;
@@ -1338,6 +1342,18 @@ static int lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
 		list_del_init(&mw->mw_item);
 		init_completion(&mw->mw_complete);
 	}
+
+	return ret;
+}
+
+static int lockres_remove_mask_waiter(struct ocfs2_lock_res *lockres,
+				      struct ocfs2_mask_waiter *mw)
+{
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&lockres->l_lock, flags);
+	ret = __lockres_remove_mask_waiter(lockres, mw);
 	spin_unlock_irqrestore(&lockres->l_lock, flags);
 
 	return ret;
@@ -1373,6 +1389,7 @@ static int __ocfs2_cluster_lock(struct ocfs2_super *osb,
 	unsigned long flags;
 	unsigned int gen;
 	int noqueue_attempted = 0;
+	int dlm_locked = 0;
 
 	ocfs2_init_mask_waiter(&mw);
 
@@ -1481,6 +1498,7 @@ again:
 			ocfs2_recover_from_dlm_error(lockres, 1);
 			goto out;
 		}
+		dlm_locked = 1;
 
 		mlog(0, "lock %s, successful return from ocfs2_dlm_lock\n",
 		     lockres->l_name);
@@ -1514,10 +1532,17 @@ out:
 	if (wait && arg_flags & OCFS2_LOCK_NONBLOCK &&
 	    mw.mw_mask & (OCFS2_LOCK_BUSY|OCFS2_LOCK_BLOCKED)) {
 		wait = 0;
-		if (lockres_remove_mask_waiter(lockres, &mw))
+		spin_lock_irqsave(&lockres->l_lock, flags);
+		if (__lockres_remove_mask_waiter(lockres, &mw)) {
+			if (dlm_locked)
+				lockres_or_flags(lockres,
+					OCFS2_LOCK_NONBLOCK_FINISHED);
+			spin_unlock_irqrestore(&lockres->l_lock, flags);
 			ret = -EAGAIN;
-		else
+		} else {
+			spin_unlock_irqrestore(&lockres->l_lock, flags);
 			goto again;
+		}
 	}
 	if (wait) {
 		ret = ocfs2_wait_for_mask(&mw);