1.\" 2.\" Copyright (c) 2004 Sun Microsystems, Inc. All Rights Reserved. 3.\" Copyright 2021 Oxide compuer Company 4.\" 5.\" The contents of this file are subject to the terms of the 6.\" Common Development and Distribution License (the "License"). 7.\" You may not use this file except in compliance with the License. 8.\" 9.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10.\" or http://www.opensolaris.org/os/licensing. 11.\" See the License for the specific language governing permissions 12.\" and limitations under the License. 13.\" 14.\" When distributing Covered Code, include this CDDL HEADER in each 15.\" file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16.\" If applicable, add the following below this CDDL HEADER, with the 17.\" fields enclosed by brackets "[]" replaced with your own identifying 18.\" information: Portions Copyright [yyyy] [name of copyright owner] 19.\" 20.Dd November 29, 2021 21.Dt DEVFS 4FS 22.Os 23.Sh NAME 24.Nm devfs 25.Nd Devices file system 26.Sh DESCRIPTION 27The 28.Nm 29filesystem manages a name space of all devices in the operating environment and 30is mounted during boot on the 31.Pa /devices 32name space. 33.Pp 34The 35.Pa /devices 36name space is dynamic and reflects the current state of accessible devices. 37The names of all attached device instances are present under 38.Pa /devices . 39.Pp 40The content under 41.Pa /devices 42is under the exclusive control of the 43.Nm 44filesystem and cannot be changed. 45.Pp 46The system may be configured to include a device in one of two ways: 47.Bl -enum 48.It 49By means of dynamic reconfiguration 50.Pq DR , 51using, for example, 52.Xr cfgadm 8 . 53Several different hardware buses such as PCIe and USB automatically discover and 54enumerate devices that they encounter. 55.It 56For devices driven by 57.Xr driver.conf 5 58enumeration, edit the 59.Pa driver.conf 60file to add a new entry, then use 61.Xr update_drv 8 62to cause the system to re-read the 63.Pa driver.conf 64file and thereby enumerate the instance. 65.El 66.Pp 67The device may be attached through a number of system calls and programs, 68including 69.Xr open 2 , 70.Xr stat 2 , 71and 72.Xr ls 1 . 73During device attach, the device driver typically creates minor nodes 74corresponding to the device via 75.Xr ddi_create_minor_node 9F . 76If the attach is successful, one or more minor nodes referring to the device are 77created under 78.Pa /devices . 79.Pp 80Operations like 81.Xr mknod 2 , 82.Xr mkdir 2 , 83and 84.Xr creat 2 85are not supported in 86.Pa /devices . 87.Pp 88This file system is not present in a non-global zone. 89.Sh FILES 90.Bl -tag -width Pa 91.It Pa /devices 92Mount point for 93.Nm 94file system in the global zone. 95.El 96.Sh SEE ALSO 97.Xr vfstab 5 , 98.Xr devfsadm 8 , 99.Xr attach 9E 100.Sh NOTES 101The 102.Pa /devices 103name space cannot be unmounted. 104.Pp 105All content at or below the 106.Pa /devices 107name space is an implementation 108artifact and subject to incompatible change or removal without notification. 109Generally, user programs should leverage the device name space under 110.Pa /dev . 111