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diff --git a/share/man/man7/ffs.7 b/share/man/man7/ffs.7 new file mode 100644 index 000000000000..fc8c61a3ad24 --- /dev/null +++ b/share/man/man7/ffs.7 @@ -0,0 +1,226 @@ +.\" Copyright (c) 2001 Networks Associates Technology, Inc. +.\" All rights reserved. +.\" +.\" This software was developed for the FreeBSD Project by Chris +.\" Costello at Safeport Network Services and NAI Labs, the Security +.\" Research Division of Network Associates, Inc. under DARPA/SPAWAR +.\" contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS +.\" research program. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd December 26, 2001 +.Dt FFS 7 +.Os +.Sh NAME +.Nm ffs +.Nd Berkeley fast file system +.Sh SYNOPSIS +In the kernel configuration file: +.Cd "options FFS" +.Cd "options QUOTA" +.Cd "options SOFTUPDATES" +.Cd "options SUIDDIR" +.Cd "options UFS_ACL" +.Cd "options UFS_DIRHASH" +.Cd "options UFS_EXTATTR" +.Cd "options UFS_EXTATTR_AUTOSTART" +.Pp +In +.Xr fstab 5 : +.Bd -literal -compact +/dev/disk0a /mnt ufs rw 1 1 +.Ed +.Sh DESCRIPTION +The Berkeley fast file system +provides facilities to store file system data onto a disk device. +.Nm +has been optimized over the years +for speed and reliability +and is the default +.Fx +file system. +.Ss Quotas +.Bl -tag -width 2n +.It Cd "options QUOTA" +This option allows system administrators +to set limits on disk usage +on a per-user basis. +Quotas can be used only on file systems +mounted with the +.Cm quota +option; +see +.Xr quota 1 +and +.Xr edquota 8 . +.El +.Ss Soft Updates +.Bl -tag -width 2n +.It Cd "options SOFTUPDATES" +The soft updates feature tracks writes to the disk +and enforces metadata update dependencies +(e.g., updating free block maps) +to ensure that the file system remains consistent. +.Pp +To enable soft updates on an +.Em unmounted +file system, use the following command: +.Pp +.D1 Nm tunefs Fl n Cm enable Ar fs +.Pp +.Ar fs +can be either a mount point listed in +.Xr fstab 5 +(e.g., +.Pa /usr ) , +or a disk device +(e.g., +.Pa /dev/da0a ) . +.El +.Ss File Ownership Inheritance +.Bl -tag -width 2n +.It Cd "options SUIDDIR" +For use in file sharing environments +on networks including +.Tn "Microsoft Windows" +and +.Tn "Apple Macintosh" +computers, +this option allows files on file systems +mounted with the +.Cm suiddir +option +to inherit the ownership of its directory, +i.e., +.Dq "if it's my directory, it must be my file." +.El +.Ss Access Control Lists +.Bl -tag -width 2n +.It Cd "options UFS_ACL" +Access control lists allow the association of +fine-grained discretionary access control information +with files and directories. +This option requires the presence of the +.Dv UFS_EXTATTR +option, and it is recommended that +.Dv UFS_EXTATTR_AUTOSTART +is included as well, +so that ACLs are enabled atomically upon mounting the file system. +.El +.Pp +In order to enable support for ACLs, +two extended attributes must be available in the +.Dv EXTATTR_NAMESPACE_SYSTEM +namespace: +.Pa posix1e.acl_access , +which holds the access ACL, +and +.Pa posix1e.acl_default , +which holds the default ACL for directories. +If you are using file system extended attributes, +the following commands may be used to +allocate space for and create the necessary EA backing files +for ACLs in the root of each file system. +In these examples, the root file system is used; +see +.Sx "Extended Attributes" +for more details. +.Bd -literal -offset indent +mkdir -p /.attribute/system +cd /.attribute/system +extattrctl initattr -p / 388 posix1e.acl_access +extattrctl initattr -p / 388 posix1e.acl_default +.Ed +.Pp +On the next mount of the root file system, +the attributes will be automatically started +(if +.Dv UFS_EXTATTR_AUTOSTART +is included in the kernel configuration), +and ACLs will be enabled. +.Ss Directory Hashing +.Bl -tag -width 2n +.It Cd "options UFS_DIRHASH" +Implements a hash-based lookup scheme for directories +in order to speed up accesses to very large directories. +.El +.Ss Extended Attributes +.Bl -tag -width 2n +.It Cd "options UFS_EXTATTR" +Extended attributes allow the association of +additional arbitrary metadata with files and directories, +which can be assigned and retrieved from userland +as well as from within the kernel; see +.Xr extattrctl 8 . +.It Cd "options UFS_EXTATTR_AUTOSTART" +If this option is defined, +.Nm +will search for a +.Pa .attribute +subdirectory of the file system root during the mount operation. +If found, extended attribute support will be +automatically started for that file system. +.El +.Pp +The following +.Xr sysctl 8 +MIBs are defined for use with +.Nm : +.Bl -hang -width ".Va vfs.ffs.doreallocblk" +.It Va vfs.ffs.doasyncfree +Asynchronously write out modified i-node and indirect blocks +upon reallocating file system blocks to be contiguous. +(Default: 1.) +.It Va vfs.ffs.doreallocblks +Enable support for the rearrangement of blocks +to be contiguous. +(Default: 1.) +.El +.Sh SEE ALSO +.Xr quota 1 , +.Xr acl 3 , +.Xr extattr 3 , +.Xr edquota 8 , +.Xr extattrctl 8 , +.Xr sysctl 8 +.Rs +.%A M. McKusick +.%A W. Joy +.%A S. Leffler +.%A R. Fabry +.%D August 1984 +.%T "A Fast File System for UNIX" +.%J "ACM Transactions on Computer Systems" +.%N 2 +.%V 3 +.%P 181-197 +.Re +.Rs +.%A M. McKusick +.%D June 2000 +.%T "Soft Updates: A Technique for Eliminating Most Synchronous Writes in the Fast Filesystem" +.%J "Proceedings of the Freenix Track at the 1999 Usenix Annual Technical Conference" +.%P 71-84 +.Re |