From 3ad6f93e98d6df25d0667d847d3ab9cbdccb3eae Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 3 Jul 2017 20:14:56 -0400 Subject: [PATCH] annotate poll-related wait keys __poll_t is also used as wait key in some waitqueues. Verify that wait_..._poll() gets __poll_t as key and provide a helper for wakeup functions to get back to that __poll_t value. Signed-off-by: Al Viro --- drivers/vfio/virqfd.c | 2 +- drivers/vhost/vhost.c | 4 ++-- fs/eventpoll.c | 9 +++++---- fs/select.c | 2 +- include/linux/wait.h | 10 ++++++---- mm/memcontrol.c | 2 +- net/core/datagram.c | 4 +--- net/unix/af_unix.c | 2 +- virt/kvm/eventfd.c | 2 +- 9 files changed, 19 insertions(+), 18 deletions(-) diff --git a/drivers/vfio/virqfd.c b/drivers/vfio/virqfd.c index d18b10ff119e..8cc4b48ff127 100644 --- a/drivers/vfio/virqfd.c +++ b/drivers/vfio/virqfd.c @@ -46,7 +46,7 @@ static void virqfd_deactivate(struct virqfd *virqfd) static int virqfd_wakeup(wait_queue_entry_t *wait, unsigned mode, int sync, void *key) { struct virqfd *virqfd = container_of(wait, struct virqfd, wait); - unsigned long flags = (unsigned long)key; + __poll_t flags = key_to_poll(key); if (flags & POLLIN) { /* An event has been signaled, call function */ diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index c18e70bd0466..7aad77be0b46 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -170,7 +170,7 @@ static int vhost_poll_wakeup(wait_queue_entry_t *wait, unsigned mode, int sync, { struct vhost_poll *poll = container_of(wait, struct vhost_poll, wait); - if (!((unsigned long)key & poll->mask)) + if (!(key_to_poll(key) & poll->mask)) return 0; vhost_poll_queue(poll); @@ -211,7 +211,7 @@ int vhost_poll_start(struct vhost_poll *poll, struct file *file) mask = file->f_op->poll(file, &poll->table); if (mask) - vhost_poll_wakeup(&poll->wait, 0, 0, (void *)(uintptr_t)mask); + vhost_poll_wakeup(&poll->wait, 0, 0, poll_to_key(mask)); if (mask & POLLERR) { if (poll->wqh) remove_wait_queue(poll->wqh, &poll->wait); diff --git a/fs/eventpoll.c b/fs/eventpoll.c index afd548ebc328..21e6fee00e8b 100644 --- a/fs/eventpoll.c +++ b/fs/eventpoll.c @@ -1117,6 +1117,7 @@ static int ep_poll_callback(wait_queue_entry_t *wait, unsigned mode, int sync, v unsigned long flags; struct epitem *epi = ep_item_from_wait(wait); struct eventpoll *ep = epi->ep; + __poll_t pollflags = key_to_poll(key); int ewake = 0; spin_lock_irqsave(&ep->lock, flags); @@ -1138,7 +1139,7 @@ static int ep_poll_callback(wait_queue_entry_t *wait, unsigned mode, int sync, v * 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)) + if (pollflags && !(pollflags & epi->event.events)) goto out_unlock; /* @@ -1175,8 +1176,8 @@ static int ep_poll_callback(wait_queue_entry_t *wait, unsigned mode, int sync, v */ if (waitqueue_active(&ep->wq)) { if ((epi->event.events & EPOLLEXCLUSIVE) && - !((unsigned long)key & POLLFREE)) { - switch ((unsigned long)key & EPOLLINOUT_BITS) { + !(pollflags & POLLFREE)) { + switch (pollflags & EPOLLINOUT_BITS) { case POLLIN: if (epi->event.events & POLLIN) ewake = 1; @@ -1205,7 +1206,7 @@ static int ep_poll_callback(wait_queue_entry_t *wait, unsigned mode, int sync, v if (!(epi->event.events & EPOLLEXCLUSIVE)) ewake = 1; - if ((unsigned long)key & POLLFREE) { + if (pollflags & POLLFREE) { /* * If we race with ep_remove_wait_queue() it can miss * ->whead = NULL and do another remove_wait_queue() after diff --git a/fs/select.c b/fs/select.c index b2bf84be5056..ffc16fd3673e 100644 --- a/fs/select.c +++ b/fs/select.c @@ -212,7 +212,7 @@ static int pollwake(wait_queue_entry_t *wait, unsigned mode, int sync, void *key struct poll_table_entry *entry; entry = container_of(wait, struct poll_table_entry, wait); - if (key && !((unsigned long)key & entry->key)) + if (key && !(key_to_poll(key) & entry->key)) return 0; return __pollwake(wait, mode, sync, key); } diff --git a/include/linux/wait.h b/include/linux/wait.h index 158715445ffb..55a611486bac 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -206,14 +206,16 @@ void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode, int nr); /* * Wakeup macros to be used to report events to the targets. */ +#define poll_to_key(m) ((void *)(__force uintptr_t)(__poll_t)(m)) +#define key_to_poll(m) ((__force __poll_t)(uintptr_t)(void *)(m)) #define wake_up_poll(x, m) \ - __wake_up(x, TASK_NORMAL, 1, (void *) (m)) + __wake_up(x, TASK_NORMAL, 1, poll_to_key(m)) #define wake_up_locked_poll(x, m) \ - __wake_up_locked_key((x), TASK_NORMAL, (void *) (m)) + __wake_up_locked_key((x), TASK_NORMAL, poll_to_key(m)) #define wake_up_interruptible_poll(x, m) \ - __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m)) + __wake_up(x, TASK_INTERRUPTIBLE, 1, poll_to_key(m)) #define wake_up_interruptible_sync_poll(x, m) \ - __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m)) + __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, poll_to_key(m)) #define ___wait_cond_timeout(condition) \ ({ \ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 50e6906314f8..006aa27f4fb4 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3777,7 +3777,7 @@ static int memcg_event_wake(wait_queue_entry_t *wait, unsigned mode, struct mem_cgroup_event *event = container_of(wait, struct mem_cgroup_event, wait); struct mem_cgroup *memcg = event->memcg; - unsigned long flags = (unsigned long)key; + __poll_t flags = key_to_poll(key); if (flags & POLLHUP) { /* diff --git a/net/core/datagram.c b/net/core/datagram.c index 522873ed120b..000da13c01f2 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -72,12 +72,10 @@ static inline int connection_based(struct sock *sk) static int receiver_wake_function(wait_queue_entry_t *wait, unsigned int mode, int sync, void *key) { - unsigned long bits = (unsigned long)key; - /* * Avoid a wakeup if event not interesting for us */ - if (bits && !(bits & (POLLIN | POLLERR))) + if (key && !(key_to_poll(key) & (POLLIN | POLLERR))) return 0; return autoremove_wake_function(wait, mode, sync, key); } diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index a9ee634f3c42..72957961ac22 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -367,7 +367,7 @@ static int unix_dgram_peer_wake_relay(wait_queue_entry_t *q, unsigned mode, int /* relaying can only happen while the wq still exists */ u_sleep = sk_sleep(&u->sk); if (u_sleep) - wake_up_interruptible_poll(u_sleep, key); + wake_up_interruptible_poll(u_sleep, key_to_poll(key)); return 0; } diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index a1f68ed999d8..a334399fafec 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -188,7 +188,7 @@ irqfd_wakeup(wait_queue_entry_t *wait, unsigned mode, int sync, void *key) { struct kvm_kernel_irqfd *irqfd = container_of(wait, struct kvm_kernel_irqfd, wait); - unsigned long flags = (unsigned long)key; + __poll_t flags = key_to_poll(key); struct kvm_kernel_irq_routing_entry irq; struct kvm *kvm = irqfd->kvm; unsigned seq; -- GitLab