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io_uring_register_zcrx_ctrl

liburing_rs

Function io_uring_register_zcrx_ctrl 

Source 
pub unsafe extern "C" fn io_uring_register_zcrx_ctrl(
    ring: *mut io_uring,
    ctrl: *mut zcrx_ctrl,
) -> c_int
Expand description

Perform control operations on a zero-copy receive context

§DESCRIPTION

The io_uring_register_zcrx_ctrl function performs control operations on a previously registered zero-copy receive context. See io_uring_register_ifq for details on registering a zero-copy receive context.

The ctrl argument must point to a struct zcrx_ctrl structure that describes the control operation to perform:

struct zcrx_ctrl {
    __u32 zcrx_id;
    __u32 op;
    __u64 __resv[2];
    union {
        struct zcrx_ctrl_export     zc_export;
        struct zcrx_ctrl_flush_rq   zc_flush;
    };
};

The zcrx_id field must be set to the ID of the zero-copy receive context returned from io_uring_register_ifq. The op field specifies the control operation to perform and can be one of:

ZCRX_CTRL_FLUSH_RQ
Flushes pending buffers from the refill queue. Uses the zc_flush member of the union.

ZCRX_CTRL_EXPORT
Exports the zero-copy receive context for use by other rings. Uses the zc_export member of the union. Upon successful export, the zcrx_fd field in zc_export will contain the file descriptor that can be used to share this context with other io_uring instances.

The reserved __resv fields must be cleared to zero.

§RETURN VALUE

Returns 0 on success. On error, a negative errno value is returned.

§NOTES

This function is available since Linux kernel 6.15.

§SEE ALSO

io_uring_register, io_uring_register_ifq