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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-11 22:57:19 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-11 22:57:19 +0100 |
commit | ee5daa1361fceb6f482c005bcc9ba8d01b92ea5c (patch) | |
tree | 71736f733c7efec13218756ab8635b258b8a1c53 /fs/eventpoll.c | |
parent | Merge tag 'xtensa-20180211' of git://github.com/jcmvbkbc/linux-xtensa (diff) | |
parent | annotate ep_scan_ready_list() (diff) | |
download | linux-ee5daa1361fceb6f482c005bcc9ba8d01b92ea5c.tar.xz linux-ee5daa1361fceb6f482c005bcc9ba8d01b92ea5c.zip |
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.c | 41 |
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) |