futex: make futex_parse_waitv() available as a helper

To make it more generically useful, augment it with allowing the caller
to pass in the wake handler and wake data. Convert the futex_waitv()
syscall, passing in the default handlers.

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2023-06-13 08:31:58 -06:00
parent 8af1692616
commit 5177c0cb30
2 changed files with 16 additions and 5 deletions

View file

@ -361,6 +361,11 @@ struct futex_vector {
struct futex_q q;
};
extern int futex_parse_waitv(struct futex_vector *futexv,
struct futex_waitv __user *uwaitv,
unsigned int nr_futexes, futex_wake_fn *wake,
void *wake_data);
extern int futex_wait_multiple(struct futex_vector *vs, unsigned int count,
struct hrtimer_sleeper *to);

View file

@ -184,12 +184,15 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
* @futexv: Kernel side list of waiters to be filled
* @uwaitv: Userspace list to be parsed
* @nr_futexes: Length of futexv
* @wake: Wake to call when futex is woken
* @wake_data: Data for the wake handler
*
* Return: Error code on failure, 0 on success
*/
static int futex_parse_waitv(struct futex_vector *futexv,
struct futex_waitv __user *uwaitv,
unsigned int nr_futexes)
int futex_parse_waitv(struct futex_vector *futexv,
struct futex_waitv __user *uwaitv,
unsigned int nr_futexes, futex_wake_fn *wake,
void *wake_data)
{
struct futex_waitv aux;
unsigned int i;
@ -214,6 +217,8 @@ static int futex_parse_waitv(struct futex_vector *futexv,
futexv[i].w.val = aux.val;
futexv[i].w.uaddr = aux.uaddr;
futexv[i].q = futex_q_init;
futexv[i].q.wake = wake;
futexv[i].q.wake_data = wake_data;
}
return 0;
@ -306,7 +311,8 @@ SYSCALL_DEFINE5(futex_waitv, struct futex_waitv __user *, waiters,
goto destroy_timer;
}
ret = futex_parse_waitv(futexv, waiters, nr_futexes);
ret = futex_parse_waitv(futexv, waiters, nr_futexes, futex_wake_mark,
NULL);
if (!ret)
ret = futex_wait_multiple(futexv, nr_futexes, timeout ? &to : NULL);
@ -421,7 +427,7 @@ SYSCALL_DEFINE4(futex_requeue,
if (!waiters)
return -EINVAL;
ret = futex_parse_waitv(futexes, waiters, 2);
ret = futex_parse_waitv(futexes, waiters, 2, futex_wake_mark, NULL);
if (ret)
return ret;