mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 02:39:48 +00:00
![Jens Axboe](/assets/img/avatar_default.png)
Various fixes and changes have been applied to liburing since we copied some select bits to the kernel testing/examples part, sync up with liburing to get those changes. Most notable is the change that split the CQE reading into the peek and seen event, instead of being just a single function. Also fixes an unsigned wrap issue in io_uring_submit(), leak of 'fd' in setup if we fail, and various other little issues. Signed-off-by: Jens Axboe <axboe@kernel.dk>
107 lines
2.8 KiB
C
107 lines
2.8 KiB
C
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/mman.h>
|
|
#include <unistd.h>
|
|
#include <errno.h>
|
|
#include <string.h>
|
|
|
|
#include "liburing.h"
|
|
|
|
static int io_uring_mmap(int fd, struct io_uring_params *p,
|
|
struct io_uring_sq *sq, struct io_uring_cq *cq)
|
|
{
|
|
size_t size;
|
|
void *ptr;
|
|
int ret;
|
|
|
|
sq->ring_sz = p->sq_off.array + p->sq_entries * sizeof(unsigned);
|
|
ptr = mmap(0, sq->ring_sz, PROT_READ | PROT_WRITE,
|
|
MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQ_RING);
|
|
if (ptr == MAP_FAILED)
|
|
return -errno;
|
|
sq->khead = ptr + p->sq_off.head;
|
|
sq->ktail = ptr + p->sq_off.tail;
|
|
sq->kring_mask = ptr + p->sq_off.ring_mask;
|
|
sq->kring_entries = ptr + p->sq_off.ring_entries;
|
|
sq->kflags = ptr + p->sq_off.flags;
|
|
sq->kdropped = ptr + p->sq_off.dropped;
|
|
sq->array = ptr + p->sq_off.array;
|
|
|
|
size = p->sq_entries * sizeof(struct io_uring_sqe);
|
|
sq->sqes = mmap(0, size, PROT_READ | PROT_WRITE,
|
|
MAP_SHARED | MAP_POPULATE, fd,
|
|
IORING_OFF_SQES);
|
|
if (sq->sqes == MAP_FAILED) {
|
|
ret = -errno;
|
|
err:
|
|
munmap(sq->khead, sq->ring_sz);
|
|
return ret;
|
|
}
|
|
|
|
cq->ring_sz = p->cq_off.cqes + p->cq_entries * sizeof(struct io_uring_cqe);
|
|
ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE,
|
|
MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING);
|
|
if (ptr == MAP_FAILED) {
|
|
ret = -errno;
|
|
munmap(sq->sqes, p->sq_entries * sizeof(struct io_uring_sqe));
|
|
goto err;
|
|
}
|
|
cq->khead = ptr + p->cq_off.head;
|
|
cq->ktail = ptr + p->cq_off.tail;
|
|
cq->kring_mask = ptr + p->cq_off.ring_mask;
|
|
cq->kring_entries = ptr + p->cq_off.ring_entries;
|
|
cq->koverflow = ptr + p->cq_off.overflow;
|
|
cq->cqes = ptr + p->cq_off.cqes;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* For users that want to specify sq_thread_cpu or sq_thread_idle, this
|
|
* interface is a convenient helper for mmap()ing the rings.
|
|
* Returns -1 on error, or zero on success. On success, 'ring'
|
|
* contains the necessary information to read/write to the rings.
|
|
*/
|
|
int io_uring_queue_mmap(int fd, struct io_uring_params *p, struct io_uring *ring)
|
|
{
|
|
int ret;
|
|
|
|
memset(ring, 0, sizeof(*ring));
|
|
ret = io_uring_mmap(fd, p, &ring->sq, &ring->cq);
|
|
if (!ret)
|
|
ring->ring_fd = fd;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Returns -1 on error, or zero on success. On success, 'ring'
|
|
* contains the necessary information to read/write to the rings.
|
|
*/
|
|
int io_uring_queue_init(unsigned entries, struct io_uring *ring, unsigned flags)
|
|
{
|
|
struct io_uring_params p;
|
|
int fd, ret;
|
|
|
|
memset(&p, 0, sizeof(p));
|
|
p.flags = flags;
|
|
|
|
fd = io_uring_setup(entries, &p);
|
|
if (fd < 0)
|
|
return fd;
|
|
|
|
ret = io_uring_queue_mmap(fd, &p, ring);
|
|
if (ret)
|
|
close(fd);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void io_uring_queue_exit(struct io_uring *ring)
|
|
{
|
|
struct io_uring_sq *sq = &ring->sq;
|
|
struct io_uring_cq *cq = &ring->cq;
|
|
|
|
munmap(sq->sqes, *sq->kring_entries * sizeof(struct io_uring_sqe));
|
|
munmap(sq->khead, sq->ring_sz);
|
|
munmap(cq->khead, cq->ring_sz);
|
|
close(ring->ring_fd);
|
|
}
|