1.\" $NetBSD: cpu_rootconf.9,v 1.10 2014/11/26 20:46:46 wiz Exp $ 2.\" 3.\" Copyright (c) 2002 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Gregory McGarry. 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd November 11, 2014 31.Dt CPU_ROOTCONF 9 32.Os 33.Sh NAME 34.Nm cpu_rootconf , 35.Nm rootconf , 36.Nm setroot 37.Nd root file system setup 38.Sh SYNOPSIS 39.In sys/types.h 40.In sys/systm.h 41.Ft void 42.Fn cpu_rootconf "void" 43.Ft void 44.Fn rootconf "void" 45.Ft void 46.Fn setroot "device_t bootdv" "int bootpartition" 47.Sh DESCRIPTION 48The 49.Fn cpu_rootconf 50is a machine-dependent interface invoked during system bootstrap to 51determine the root file system device and initialize machine-dependent 52file system state. 53.Fn cpu_rootconf 54provides the global variables 55.Fa booted_device , 56.Fa booted_partition , 57.Fa booted_startblk , 58.Fa booted_nblks , 59and 60.Fa bootspec . 61.Fa cpu_rootconf 62invokes the machine-independent function 63.Fa rootconf 64which calls the function 65.Fa setroot 66to record the root device and the root partition information 67for use in machine-independent code. 68.Pp 69.Fa rootconf 70may adjust the global variables and determines the parameters 71for setroot. 72This is for example used to translate a device 73and partition number provided by the bootloader into a disk 74wedge device covering the same partition. 75.Pp 76If the bootloader already identified a disk wedge, it passes 77a non-zero value for 78.Fa booted_nblks , 79then 80.Fa booted_startblk 81and 82.Fa booted_nblks 83specify a disk wedge as the boot device. 84.Pp 85.Fa setroot 86evaluates several sources to identify the root device in the 87following order until a valid device is selected: 88.Bl -enum 89.It 90The kernel configuration variable 91.Fa rootspec 92which is set by 93.Xr config 1 . 94The value is the name and unit of the root device, e.g., "sd0" (disk) 95or "dk0" (wedge) or "le0" (network) or the prefix "wedge:" followed 96by the name of the disk wedge. 97For disk devices the partition passed as argument to 98.Fa setroot 99is used. 100.It 101The variable 102.Fa bootspec 103following the same syntax. 104.It 105The result of an interactive query of the root device if 106.Fa boothowto 107has set the flag 108.Dv RB_ASKNAME . 109The input uses the same syntax as the previous sources. 110Here also the kernel dump device is queried. 111.It 112The boot device and partition passed as arguments. 113.El 114.Pp 115If a root device cannot be selected, 116.Fa setroot 117sets the 118.Dv RB_ASKNAME 119flag and loops. 120.Pp 121Otherwise the kernel dump device is identified in a similar 122manner from 123.Bl -enum 124.It 125The result of a previous interactive query. 126See above. 127.It 128The kernel configuration variable 129.Fa dumpspec , 130if set. 131.It 132The second partition of the root device, if it is a regular disk. 133.It 134The first disk wedge device of type DKW_PTYPE_SWAP. 135.El 136.Sh SEE ALSO 137.Xr config 1 , 138.Xr dk 4 , 139.Xr boot 8 , 140.Xr boothowto 9 141