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. 72This allows locks and other synchronization primitives 73to be inlined safely. 74.Pp 75The arguments are: 76.Bl -tag -width indent 77.It Fa name 78The module name, which will be used in the 79.Fn SYSINIT 80call to identify the module. 81.It Fa data 82A 83.Vt moduledata_t 84structure, which contains two main items, the official name of the 85module name, which will be used in the 86.Vt module_t 87structure and a pointer to the event handler function of type 88.Vt modeventhand_t . 89.It Fa sub 90An argument directed to the 91.Fn SYSINIT 92macro. 93Valid values for this are contained in the 94.Vt sysinit_sub_id 95enumeration 96(see 97.In sys/kernel.h ) 98and specify the type of system startup interfaces. 99The 100.Xr DRIVER_MODULE 9 101macro uses a value of 102.Dv SI_SUB_DRIVERS 103here for example, since these modules contain a driver for a device. 104For kernel modules that are loaded at runtime, a value of 105.Dv SI_SUB_EXEC 106is common. 107.It Fa order 108An argument for 109.Fn SYSINIT . 110It represents the KLDs order of initialization within the subsystem. 111Valid values are defined in the 112.Vt sysinit_elem_order 113enumeration 114.Pq In sys/kernel.h . 115.El 116.Sh SEE ALSO 117.Xr DEV_MODULE 9 , 118.Xr DRIVER_MODULE 9 , 119.Xr module 9 , 120.Xr SYSCALL_MODULE 9 121.Pp 122.Pa /usr/include/sys/kernel.h , 123.Pa /usr/share/examples/kld 124.Sh AUTHORS 125.An -nosplit 126This manual page was written by 127.An Alexander Langer Aq Mt alex@FreeBSD.org , 128inspired by the KLD Facility Programming Tutorial by 129.An Andrew Reiter Aq Mt arr@watson.org . 130