1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 2000 Alexander Langer 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.\" $FreeBSD$ 30.\" 31.Dd February 13, 2018 32.Dt DECLARE_MODULE 9 33.Os 34.Sh NAME 35.Nm DECLARE_MODULE 36.Nd kernel module declaration macro 37.Sh SYNOPSIS 38.In sys/param.h 39.In sys/kernel.h 40.In sys/module.h 41.Fn DECLARE_MODULE "name" "moduledata_t data" "sub" "order" 42.Fn DECLARE_MODULE_TIED "name" "moduledata_t data" "sub" "order" 43.Sh DESCRIPTION 44The 45.Fn DECLARE_MODULE 46macro declares a generic kernel module. 47It is used to register the module with the system, using the 48.Fn SYSINIT 49macro. 50.Fn DECLARE_MODULE 51is usually used within other macros, such as 52.Xr DRIVER_MODULE 9 , 53.Xr DEV_MODULE 9 54and 55.Xr SYSCALL_MODULE 9 . 56Of course, it can also be called directly, for example in 57order to implement dynamic sysctls. 58.Pp 59A module declared with 60.Fn DECLARE_MODULE_TIED 61will load only if the running kernel version 62(as specified by 63.Dv __FreeBSD_version ) 64is identical to that on which it was built. 65This declaration should be used by modules which depend on interfaces beyond 66the stable kernel KBI (such as ABI emulators or hypervisors that rely on 67internal kernel structures). 68.Fn DECLARE_MODULE 69will behave like 70.Fn DECLARE_MODULE_TIED 71when compiled with modules built with the kernel. This allows locks and 72other synchronization primitives to be inlined safely. 73.Pp 74The arguments are: 75.Bl -tag -width indent 76.It Fa name 77The module name, which will be used in the 78.Fn SYSINIT 79call to identify the module. 80.It Fa data 81A 82.Vt moduledata_t 83structure, which contains two main items, the official name of the 84module name, which will be used in the 85.Vt module_t 86structure and a pointer to the event handler function of type 87.Vt modeventhand_t . 88.It Fa sub 89An argument directed to the 90.Fn SYSINIT 91macro. 92Valid values for this are contained in the 93.Vt sysinit_sub_id 94enumeration 95(see 96.In sys/kernel.h ) 97and specify the type of system startup interfaces. 98The 99.Xr DRIVER_MODULE 9 100macro uses a value of 101.Dv SI_SUB_DRIVERS 102here for example, since these modules contain a driver for a device. 103For kernel modules that are loaded at runtime, a value of 104.Dv SI_SUB_EXEC 105is common. 106.It Fa order 107An argument for 108.Fn SYSINIT . 109It represents the KLDs order of initialization within the subsystem. 110Valid values are defined in the 111.Vt sysinit_elem_order 112enumeration 113.Pq In sys/kernel.h . 114.El 115.Sh SEE ALSO 116.Xr DEV_MODULE 9 , 117.Xr DRIVER_MODULE 9 , 118.Xr module 9 , 119.Xr SYSCALL_MODULE 9 120.Pp 121.Pa /usr/include/sys/kernel.h , 122.Pa /usr/share/examples/kld 123.Sh AUTHORS 124.An -nosplit 125This manual page was written by 126.An Alexander Langer Aq Mt alex@FreeBSD.org , 127inspired by the KLD Facility Programming Tutorial by 128.An Andrew Reiter Aq Mt arr@watson.org . 129