123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107 |
- #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);
- }
|