io_uring_prep_madvise(3) liburing Manual io_uring_prep_madvise(3)

io_uring_prep_madvise - prepare a madvise request

#include <sys/mman.h>
#include <liburing.h>
void io_uring_prep_madvise(struct io_uring_sqe *sqe,
                           void *addr,
                           __u32 len,
                           int advice);

void io_uring_prep_madvise64(struct io_uring_sqe *sqe,
                             void *addr,
                             __u64 len,
                             int advice);

The io_uring_prep_madvise(3) function prepares an madvise request. The submission queue entry sqe is setup to start an madvise operation at the virtual address of addr and of len length in bytes, giving it the advise located in advice.

The io_uring_prep_madvise64(3) function works like io_uring_prep_madvise(3) except that it takes a 64-bit length rather than just a 32-bit one. Older kernels may not support the 64-bit length variant. If this variant is attempted used on a kernel that doesn't support 64-bit lengths, then the request will get errored with -EINVAL in the results field of the CQE.

This function prepares an async madvise(2) request. See that man page for details.

None

The CQE res field will contain the result of the operation. See the related man page for details on possible values. Note that where synchronous system calls will return -1 on failure and set errno to the actual error value, io_uring never uses errno. Instead it returns the negated errno directly in the CQE res field.

io_uring_get_sqe(3), io_uring_submit(3), io_uring_register(2), madvise(2)

March 13, 2022 liburing-2.2