X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Feventpoll.c;h=3817149919cb81fa298686f183f67e0c86fe1c50;hb=bef5bc2464517cbbf8f85f09b5ade46904afec9a;hp=336fdb8ed47bd0bdeb69e67becd1b011eb97079f;hpb=4f0989dbfa8d18dd17c32120aac1eb3e906a62a2;p=safe%2Fjmp%2Flinux-2.6

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 336fdb8..3817149 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -98,7 +98,7 @@ struct epoll_filefd {
 struct nested_call_node {
 	struct list_head llink;
 	void *cookie;
-	int cpu;
+	void *ctx;
 };
 
 /*
@@ -251,10 +251,10 @@ ctl_table epoll_table[] = {
 		.data		= &max_user_watches,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= &proc_dointvec_minmax,
+		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= &zero,
 	},
-	{ .ctl_name = 0 }
+	{ }
 };
 #endif /* CONFIG_SYSCTL */
 
@@ -317,17 +317,17 @@ static void ep_nested_calls_init(struct nested_calls *ncalls)
  * @nproc: Nested call core function pointer.
  * @priv: Opaque data to be passed to the @nproc callback.
  * @cookie: Cookie to be used to identify this nested call.
+ * @ctx: This instance context.
  *
  * Returns: Returns the code returned by the @nproc callback, or -1 if
  *          the maximum recursion limit has been exceeded.
  */
 static int ep_call_nested(struct nested_calls *ncalls, int max_nests,
 			  int (*nproc)(void *, void *, int), void *priv,
-			  void *cookie)
+			  void *cookie, void *ctx)
 {
 	int error, call_nests = 0;
 	unsigned long flags;
-	int this_cpu = get_cpu();
 	struct list_head *lsthead = &ncalls->tasks_call_list;
 	struct nested_call_node *tncur;
 	struct nested_call_node tnode;
@@ -340,7 +340,7 @@ static int ep_call_nested(struct nested_calls *ncalls, int max_nests,
 	 * very much limited.
 	 */
 	list_for_each_entry(tncur, lsthead, llink) {
-		if (tncur->cpu == this_cpu &&
+		if (tncur->ctx == ctx &&
 		    (tncur->cookie == cookie || ++call_nests > max_nests)) {
 			/*
 			 * Ops ... loop detected or maximum nest level reached.
@@ -352,7 +352,7 @@ static int ep_call_nested(struct nested_calls *ncalls, int max_nests,
 	}
 
 	/* Add the current task and cookie to the list */
-	tnode.cpu = this_cpu;
+	tnode.ctx = ctx;
 	tnode.cookie = cookie;
 	list_add(&tnode.llink, lsthead);
 
@@ -364,16 +364,34 @@ static int ep_call_nested(struct nested_calls *ncalls, int max_nests,
 	/* Remove the current task from the list */
 	spin_lock_irqsave(&ncalls->lock, flags);
 	list_del(&tnode.llink);
- out_unlock:
+out_unlock:
 	spin_unlock_irqrestore(&ncalls->lock, flags);
 
-	put_cpu();
 	return error;
 }
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static inline void ep_wake_up_nested(wait_queue_head_t *wqueue,
+				     unsigned long events, int subclass)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave_nested(&wqueue->lock, flags, subclass);
+	wake_up_locked_poll(wqueue, events);
+	spin_unlock_irqrestore(&wqueue->lock, flags);
+}
+#else
+static inline void ep_wake_up_nested(wait_queue_head_t *wqueue,
+				     unsigned long events, int subclass)
+{
+	wake_up_poll(wqueue, events);
+}
+#endif
+
 static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests)
 {
-	wake_up_nested((wait_queue_head_t *) cookie, 1 + call_nests);
+	ep_wake_up_nested((wait_queue_head_t *) cookie, POLLIN,
+			  1 + call_nests);
 	return 0;
 }
 
@@ -389,8 +407,12 @@ static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests)
  */
 static void ep_poll_safewake(wait_queue_head_t *wq)
 {
+	int this_cpu = get_cpu();
+
 	ep_call_nested(&poll_safewake_ncalls, EP_MAX_NESTS,
-		       ep_poll_wakeup_proc, NULL, wq);
+		       ep_poll_wakeup_proc, NULL, wq, (void *) (long) this_cpu);
+
+	put_cpu();
 }
 
 /*
@@ -644,7 +666,7 @@ static unsigned int ep_eventpoll_poll(struct file *file, poll_table *wait)
 	 * could re-enter here.
 	 */
 	pollflags = ep_call_nested(&poll_readywalk_ncalls, EP_MAX_NESTS,
-				   ep_poll_readyevents_proc, ep, ep);
+				   ep_poll_readyevents_proc, ep, ep, current);
 
 	return pollflags != -1 ? pollflags : 0;
 }
@@ -783,6 +805,15 @@ static int ep_poll_callback(wait_queue_t *wait, unsigned mode, int sync, void *k
 		goto out_unlock;
 
 	/*
+	 * Check the events coming with the callback. At this stage, not
+	 * every device reports the events in the "key" parameter of the
+	 * callback. We need to be able to handle both cases here, hence the
+	 * test for "key" != NULL before the event match test.
+	 */
+	if (key && !((unsigned long) key & epi->event.events))
+		goto out_unlock;
+
+	/*
 	 * If we are trasfering events to userspace, we can hold no locks
 	 * (because we're accessing user memory, and because of linux f_op->poll()
 	 * semantics). All the events that happens during that period of time are
@@ -1109,8 +1140,7 @@ retry:
 		 * ep_poll_callback() when events will become available.
 		 */
 		init_waitqueue_entry(&wait, current);
-		wait.flags |= WQ_FLAG_EXCLUSIVE;
-		__add_wait_queue(&ep->wq, &wait);
+		__add_wait_queue_exclusive(&ep->wq, &wait);
 
 		for (;;) {
 			/*
@@ -1175,7 +1205,7 @@ SYSCALL_DEFINE1(epoll_create1, int, flags)
 	 * a file structure and a free file descriptor.
 	 */
 	error = anon_inode_getfd("[eventpoll]", &eventpoll_fops, ep,
-				 flags & O_CLOEXEC);
+				 O_RDWR | (flags & O_CLOEXEC));
 	if (error < 0)
 		ep_free(ep);
 
@@ -1184,7 +1214,7 @@ SYSCALL_DEFINE1(epoll_create1, int, flags)
 
 SYSCALL_DEFINE1(epoll_create, int, size)
 {
-	if (size < 0)
+	if (size <= 0)
 		return -EINVAL;
 
 	return sys_epoll_create1(0);
@@ -1254,7 +1284,6 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 	case EPOLL_CTL_ADD:
 		if (!epi) {
 			epds.events |= POLLERR | POLLHUP;
-
 			error = ep_insert(ep, &epds, tfile, fd);
 		} else
 			error = -EEXIST;