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#ifndef LIB_URING_H
#define LIB_URING_H
#ifdef __cplusplus
extern "C" {
#endif
#include <sys/uio.h>
#include <signal.h>
#include <string.h>
#include <inttypes.h>
#include "compat.h"
#include "io_uring.h"
#include "barrier.h"
/*
* Library interface to io_uring
*/
struct io_uring_sq {
unsigned *khead;
unsigned *ktail;
unsigned *kring_mask;
unsigned *kring_entries;
unsigned *kflags;
unsigned *kdropped;
unsigned *array;
struct io_uring_sqe *sqes;
unsigned sqe_head;
unsigned sqe_tail;
size_t ring_sz;
void *ring_ptr;
};
struct io_uring_cq {
unsigned *khead;
unsigned *ktail;
unsigned *kring_mask;
unsigned *kring_entries;
unsigned *koverflow;
struct io_uring_cqe *cqes;
size_t ring_sz;
void *ring_ptr;
};
struct io_uring {
struct io_uring_sq sq;
struct io_uring_cq cq;
unsigned flags;
int ring_fd;
};
/*
* System calls
*/
extern int io_uring_setup(unsigned entries, struct io_uring_params *p);
extern int io_uring_enter(unsigned fd, unsigned to_submit,
unsigned min_complete, unsigned flags, sigset_t *sig);
extern int io_uring_register(int fd, unsigned int opcode, const void *arg,
unsigned int nr_args);
/*
* Library interface
*/
extern int io_uring_queue_init(unsigned entries, struct io_uring *ring,
unsigned flags);
extern int io_uring_queue_mmap(int fd, struct io_uring_params *p,
struct io_uring *ring);
extern void io_uring_queue_exit(struct io_uring *ring);
extern int io_uring_peek_cqe(struct io_uring *ring,
struct io_uring_cqe **cqe_ptr);
extern int io_uring_wait_cqe(struct io_uring *ring,
struct io_uring_cqe **cqe_ptr);
extern int io_uring_submit(struct io_uring *ring);
extern int io_uring_submit_and_wait(struct io_uring *ring, unsigned wait_nr);
extern struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring);
extern int io_uring_register_buffers(struct io_uring *ring,
const struct iovec *iovecs,
unsigned nr_iovecs);
extern int io_uring_unregister_buffers(struct io_uring *ring);
extern int io_uring_register_files(struct io_uring *ring, const int *files,
unsigned nr_files);
extern int io_uring_unregister_files(struct io_uring *ring);
extern int io_uring_register_eventfd(struct io_uring *ring, int fd);
extern int io_uring_unregister_eventfd(struct io_uring *ring);
#define io_uring_for_each_cqe(ring, head, cqe) \
/* smp_load_acquire() enforces the order of tail and CQE reads. */ \
for (head = *(ring)->cq.khead; \
(cqe = (head != smp_load_acquire((ring)->cq.ktail) ? \
&(ring)->cq.cqes[head & (*(ring)->cq.kring_mask)] : NULL)); \
head++) \
/*
* Must be called after io_uring_for_each_cqe()
*/
static inline void io_uring_cq_advance(struct io_uring *ring,
unsigned nr)
{
if (nr) {
struct io_uring_cq *cq = &ring->cq;
/*
* Ensure that the kernel only sees the new value of the head
* index after the CQEs have been read.
*/
smp_store_release(cq->khead, *cq->khead + nr);
}
}
/*
* Must be called after io_uring_{peek,wait}_cqe() after the cqe has
* been processed by the application.
*/
static inline void io_uring_cqe_seen(struct io_uring *ring,
struct io_uring_cqe *cqe)
{
if (cqe)
io_uring_cq_advance(ring, 1);
}
/*
* Command prep helpers
*/
static inline void io_uring_sqe_set_data(struct io_uring_sqe *sqe, void *data)
{
sqe->user_data = (unsigned long) data;
}
static inline void *io_uring_cqe_get_data(struct io_uring_cqe *cqe)
{
return (void *) (uintptr_t) cqe->user_data;
}
static inline void io_uring_sqe_set_flags(struct io_uring_sqe *sqe,
unsigned flags)
{
sqe->flags = flags;
}
static inline void io_uring_prep_rw(int op, struct io_uring_sqe *sqe, int fd,
const void *addr, unsigned len,
off_t offset)
{
memset(sqe, 0, sizeof(*sqe));
sqe->opcode = op;
sqe->fd = fd;
sqe->off = offset;
sqe->addr = (unsigned long) addr;
sqe->len = len;
}
static inline void io_uring_prep_readv(struct io_uring_sqe *sqe, int fd,
const struct iovec *iovecs,
unsigned nr_vecs, off_t offset)
{
io_uring_prep_rw(IORING_OP_READV, sqe, fd, iovecs, nr_vecs, offset);
}
static inline void io_uring_prep_read_fixed(struct io_uring_sqe *sqe, int fd,
void *buf, unsigned nbytes,
off_t offset)
{
io_uring_prep_rw(IORING_OP_READ_FIXED, sqe, fd, buf, nbytes, offset);
}
static inline void io_uring_prep_writev(struct io_uring_sqe *sqe, int fd,
const struct iovec *iovecs,
unsigned nr_vecs, off_t offset)
{
io_uring_prep_rw(IORING_OP_WRITEV, sqe, fd, iovecs, nr_vecs, offset);
}
static inline void io_uring_prep_write_fixed(struct io_uring_sqe *sqe, int fd,
const void *buf, unsigned nbytes,
off_t offset)
{
io_uring_prep_rw(IORING_OP_WRITE_FIXED, sqe, fd, buf, nbytes, offset);
}
static inline void io_uring_prep_poll_add(struct io_uring_sqe *sqe, int fd,
short poll_mask)
{
memset(sqe, 0, sizeof(*sqe));
sqe->opcode = IORING_OP_POLL_ADD;
sqe->fd = fd;
sqe->poll_events = poll_mask;
}
static inline void io_uring_prep_poll_remove(struct io_uring_sqe *sqe,
void *user_data)
{
memset(sqe, 0, sizeof(*sqe));
sqe->opcode = IORING_OP_POLL_REMOVE;
sqe->addr = (unsigned long) user_data;
}
static inline void io_uring_prep_fsync(struct io_uring_sqe *sqe, int fd,
unsigned fsync_flags)
{
memset(sqe, 0, sizeof(*sqe));
sqe->opcode = IORING_OP_FSYNC;
sqe->fd = fd;
sqe->fsync_flags = fsync_flags;
}
static inline void io_uring_prep_nop(struct io_uring_sqe *sqe)
{
memset(sqe, 0, sizeof(*sqe));
sqe->opcode = IORING_OP_NOP;
}
#ifdef __cplusplus
}
#endif
#endif
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