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authorLinus Torvalds <torvalds@linux-foundation.org>2018-02-11 13:57:19 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2018-02-11 13:57:19 -0800
commitee5daa1361fceb6f482c005bcc9ba8d01b92ea5c (patch)
tree71736f733c7efec13218756ab8635b258b8a1c53 /fs/eventpoll.c
parent3fc928dc5308f6533d0e8004c8c63b46709a5276 (diff)
parentd85e2aa2e34dac793e70b900d865f48c69ecbc27 (diff)
Merge branch 'work.poll2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more poll annotation updates from Al Viro: "This is preparation to solving the problems you've mentioned in the original poll series. After this series, the kernel is ready for running for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done as a for bulk search-and-replace. After that, the kernel is ready to apply the patch to unify {de,}mangle_poll(), and then get rid of kernel-side POLL... uses entirely, and we should be all done with that stuff. Basically, that's what you suggested wrt KPOLL..., except that we can use EPOLL... instead - they already are arch-independent (and equal to what is currently kernel-side POLL...). After the preparations (in this series) switch to returning EPOLL... from ->poll() instances is completely mechanical and kernel-side POLL... can go away. The last step (killing kernel-side POLL... and unifying {de,}mangle_poll() has to be done after the search-and-replace job, since we need userland-side POLL... for unified {de,}mangle_poll(), thus the cherry-pick at the last step. After that we will have: - POLL{IN,OUT,...} *not* in __poll_t, so any stray instances of ->poll() still using those will be caught by sparse. - eventpoll.c and select.c warning-free wrt __poll_t - no more kernel-side definitions of POLL... - userland ones are visible through the entire kernel (and used pretty much only for mangle/demangle) - same behavior as after the first series (i.e. sparc et.al. epoll(2) working correctly)" * 'work.poll2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: annotate ep_scan_ready_list() ep_send_events_proc(): return result via esed->res preparation to switching ->poll() to returning EPOLL... add EPOLLNVAL, annotate EPOLL... and event_poll->event use linux/poll.h instead of asm/poll.h xen: fix poll misannotation smc: missing poll annotations
Diffstat (limited to 'fs/eventpoll.c')
-rw-r--r--fs/eventpoll.c41
1 files changed, 23 insertions, 18 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 42e35a6977c9..d1a490c7e6c3 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -260,6 +260,7 @@ struct ep_pqueue {
struct ep_send_events_data {
int maxevents;
struct epoll_event __user *events;
+ int res;
};
/*
@@ -660,12 +661,13 @@ static inline void ep_pm_stay_awake_rcu(struct epitem *epi)
*
* Returns: The same integer error code returned by the @sproc callback.
*/
-static int ep_scan_ready_list(struct eventpoll *ep,
- int (*sproc)(struct eventpoll *,
+static __poll_t ep_scan_ready_list(struct eventpoll *ep,
+ __poll_t (*sproc)(struct eventpoll *,
struct list_head *, void *),
void *priv, int depth, bool ep_locked)
{
- int error, pwake = 0;
+ __poll_t res;
+ int pwake = 0;
unsigned long flags;
struct epitem *epi, *nepi;
LIST_HEAD(txlist);
@@ -694,7 +696,7 @@ static int ep_scan_ready_list(struct eventpoll *ep,
/*
* Now call the callback function.
*/
- error = (*sproc)(ep, &txlist, priv);
+ res = (*sproc)(ep, &txlist, priv);
spin_lock_irqsave(&ep->lock, flags);
/*
@@ -747,7 +749,7 @@ static int ep_scan_ready_list(struct eventpoll *ep,
if (pwake)
ep_poll_safewake(&ep->poll_wait);
- return error;
+ return res;
}
static void epi_rcu_free(struct rcu_head *head)
@@ -864,7 +866,7 @@ static int ep_eventpoll_release(struct inode *inode, struct file *file)
return 0;
}
-static int ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
+static __poll_t ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
void *priv);
static void ep_ptable_queue_proc(struct file *file, wait_queue_head_t *whead,
poll_table *pt);
@@ -874,7 +876,7 @@ static void ep_ptable_queue_proc(struct file *file, wait_queue_head_t *whead,
* the ep->mtx so we need to start from depth=1, such that mutex_lock_nested()
* is correctly annotated.
*/
-static unsigned int ep_item_poll(const struct epitem *epi, poll_table *pt,
+static __poll_t ep_item_poll(const struct epitem *epi, poll_table *pt,
int depth)
{
struct eventpoll *ep;
@@ -894,7 +896,7 @@ static unsigned int ep_item_poll(const struct epitem *epi, poll_table *pt,
locked) & epi->event.events;
}
-static int ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
+static __poll_t ep_read_events_proc(struct eventpoll *ep, struct list_head *head,
void *priv)
{
struct epitem *epi, *tmp;
@@ -1414,7 +1416,8 @@ static noinline void ep_destroy_wakeup_source(struct epitem *epi)
static int ep_insert(struct eventpoll *ep, const struct epoll_event *event,
struct file *tfile, int fd, int full_check)
{
- int error, revents, pwake = 0;
+ int error, pwake = 0;
+ __poll_t revents;
unsigned long flags;
long user_watches;
struct epitem *epi;
@@ -1612,12 +1615,11 @@ static int ep_modify(struct eventpoll *ep, struct epitem *epi,
return 0;
}
-static int ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
+static __poll_t ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
void *priv)
{
struct ep_send_events_data *esed = priv;
- int eventcnt;
- unsigned int revents;
+ __poll_t revents;
struct epitem *epi;
struct epoll_event __user *uevent;
struct wakeup_source *ws;
@@ -1630,8 +1632,8 @@ static int ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
* Items cannot vanish during the loop because ep_scan_ready_list() is
* holding "mtx" during this call.
*/
- for (eventcnt = 0, uevent = esed->events;
- !list_empty(head) && eventcnt < esed->maxevents;) {
+ for (esed->res = 0, uevent = esed->events;
+ !list_empty(head) && esed->res < esed->maxevents;) {
epi = list_first_entry(head, struct epitem, rdllink);
/*
@@ -1665,9 +1667,11 @@ static int ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
__put_user(epi->event.data, &uevent->data)) {
list_add(&epi->rdllink, head);
ep_pm_stay_awake(epi);
- return eventcnt ? eventcnt : -EFAULT;
+ if (!esed->res)
+ esed->res = -EFAULT;
+ return 0;
}
- eventcnt++;
+ esed->res++;
uevent++;
if (epi->event.events & EPOLLONESHOT)
epi->event.events &= EP_PRIVATE_BITS;
@@ -1689,7 +1693,7 @@ static int ep_send_events_proc(struct eventpoll *ep, struct list_head *head,
}
}
- return eventcnt;
+ return 0;
}
static int ep_send_events(struct eventpoll *ep,
@@ -1700,7 +1704,8 @@ static int ep_send_events(struct eventpoll *ep,
esed.maxevents = maxevents;
esed.events = events;
- return ep_scan_ready_list(ep, ep_send_events_proc, &esed, 0, false);
+ ep_scan_ready_list(ep, ep_send_events_proc, &esed, 0, false);
+ return esed.res;
}
static inline struct timespec64 ep_set_mstimeout(long ms)