io_uring_register_buffers(3) — Linux manual page


io_uring_register_buffers(3) liburing Manualio_uring_register_buffers(3)

NAME         top

       io_uring_register_buffers - register buffers for fixed buffer

SYNOPSIS         top

       #include <liburing.h>

       int io_uring_register_buffers(struct io_uring *ring,
                                     const struct iovec *iovecs,
                                     unsigned nr_iovecs);

       int io_uring_register_buffers_sparse(struct io_uring *ring,
                                     unsigned nr_iovecs);

DESCRIPTION         top

       The io_uring_register_buffers(3) function registers nr_iovecs
       number of buffers defined by the array iovecs belonging to the

       The io_uring_register_buffers_sparse(3) function registers
       nr_iovecs empty buffers belonging to the ring.  These buffers
       must be updated before use, using eg

       After the caller has registered the buffers, they can be used
       with one of the fixed buffers functions.

       Registered buffers is an optimization that is useful in
       conjunction with O_DIRECT reads and writes, where it maps the
       specified range into the kernel once when the buffer is
       registered rather than doing a map and unmap for each IO every
       time IO is performed to that region. Additionally, it also avoids
       manipulating the page reference counts for each IO.

RETURN VALUE         top

       On success io_uring_register_buffers(3) and
       io_uring_register_buffers_sparse(3) return 0. On failure they
       return -errno.

SEE ALSO         top

       io_uring_get_sqe(3), io_uring_unregister_buffers(3),
       io_uring_register_buf_ring(3), io_uring_prep_read_fixed(3),

COLOPHON         top

       This page is part of the liburing (A library for io_uring)
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       was obtained from the project's upstream Git repository
       ⟨⟩ on 2022-12-17.  (At that
       time, the date of the most recent commit that was found in the
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liburing-2.1                November 15, 2021io_uring_register_buffers(3)

Pages that refer to this page: io_uring_prep_read_fixed(3)io_uring_prep_write_fixed(3)io_uring_register_buffers(3)io_uring_sqe_set_flags(3)io_uring_unregister_buffers(3)