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diff --git a/static/freebsd/man4/ffs.4 3.html b/static/freebsd/man4/ffs.4 3.html new file mode 100644 index 00000000..6c903d85 --- /dev/null +++ b/static/freebsd/man4/ffs.4 3.html @@ -0,0 +1,273 @@ +<table class="head"> + <tr> + <td class="head-ltitle">FFS(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">FFS(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">ffs</code>, <code class="Nm">ufs</code> — + <span class="Nd">Berkeley fast file system</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp">In the kernel configuration file: + <br/> + <code class="Cd">options FFS</code> + <br/> + <code class="Cd">options QUOTA</code> + <br/> + <code class="Cd">options SOFTUPDATES</code> + <br/> + <code class="Cd">options SUIDDIR</code> + <br/> + <code class="Cd">options UFS_ACL</code> + <br/> + <code class="Cd">options UFS_DIRHASH</code> + <br/> + <code class="Cd">options UFS_EXTATTR</code> + <br/> + <code class="Cd">options UFS_EXTATTR_AUTOSTART</code> + <br/> + <code class="Cd">options UFS_GJOURNAL</code></p> +<p class="Pp">In <a class="Xr">fstab(5)</a>:</p> +<div class="Bd Li"> +<pre>/dev/disk0a /mnt ufs rw 1 1</pre> +</div> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The Berkeley fast file system provides facilities to store file + system data onto a disk device. <code class="Nm">ffs</code> has been + optimized over the years for speed and reliability and is the default + <span class="Ux">FreeBSD</span> file system.</p> +<section class="Ss"> +<h2 class="Ss" id="Quotas"><a class="permalink" href="#Quotas">Quotas</a></h2> +<dl class="Bl-tag"> + <dt><code class="Cd">options QUOTA</code></dt> + <dd>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 + <code class="Cm">quota</code> option; see <a class="Xr">quota(1)</a> and + <a class="Xr">edquota(8)</a>.</dd> +</dl> +</section> +<section class="Ss"> +<h2 class="Ss" id="Soft_Updates"><a class="permalink" href="#Soft_Updates">Soft + Updates</a></h2> +<dl class="Bl-tag"> + <dt><code class="Cd">options SOFTUPDATES</code></dt> + <dd>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. + <p class="Pp">To create a new file system with the soft updates enabled, use + <a class="Xr">newfs(8)</a> command:</p> + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Nm">newfs</code> + <code class="Fl">-U</code> <var class="Ar">fs</var></div> + <p class="Pp"><var class="Ar">fs</var> can be either a mount point listed in + <a class="Xr">fstab(5)</a> (e.g., <span class="Pa">/usr</span>), or a + disk device (e.g., <span class="Pa">/dev/da0a</span>).</p> + <p class="Pp">It is possible to enable soft updates on an + <i class="Em">unmounted</i> file system by using + <a class="Xr">tunefs(8)</a> command:</p> + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Nm">tunefs</code> + <code class="Fl">-n</code> <code class="Cm">enable</code> + <var class="Ar">fs</var></div> + <p class="Pp">Soft updates can also add journaling that reduces the time + spent by <a class="Xr">fsck_ffs(8)</a> cleaning up a filesystem after a + crash from several minutes to a few seconds. The journal is placed in an + inode named <span class="Pa">.sujournal</span>, and is kept as a + circular log of segments containing records that describe metadata + operations.</p> + <p class="Pp">To create a new file system with both the soft updates and + soft updates journaling enabled, use the following command:</p> + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Nm">newfs</code> + <code class="Fl">-j</code> <var class="Ar">fs</var></div> + <p class="Pp">This runs <a class="Xr">tunefs(8)</a> command after + <a class="Xr">newfs(8)</a> command with <code class="Fl">-U</code> flag + enabled. It is possible to enable soft updates journaling on an + <i class="Em">unmounted</i> file system by using + <a class="Xr">tunefs(8)</a> command:</p> + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Nm">tunefs</code> + <code class="Fl">-j</code> <code class="Cm">enable</code> + <var class="Ar">fs</var></div> + <p class="Pp">This flag automatically enables the soft updates feature when + it is not enabled. Note that this <a class="Xr">tunefs(8)</a> command + will fail if a file <span class="Pa">.sujournal</span> already exists + before enabling the soft updates journaling.</p> + </dd> +</dl> +</section> +<section class="Ss"> +<h2 class="Ss" id="File_Ownership_Inheritance"><a class="permalink" href="#File_Ownership_Inheritance">File + Ownership Inheritance</a></h2> +<dl class="Bl-tag"> + <dt><code class="Cd">options SUIDDIR</code></dt> + <dd>For use in file sharing environments on networks including Microsoft + Windows and Apple Macintosh computers, this option allows files on file + systems mounted with the <code class="Cm">suiddir</code> option to inherit + the ownership of its directory, i.e., “if it's my directory, it + must be my file.”</dd> +</dl> +</section> +<section class="Ss"> +<h2 class="Ss" id="Access_Control_Lists"><a class="permalink" href="#Access_Control_Lists">Access + Control Lists</a></h2> +<dl class="Bl-tag"> + <dt><code class="Cd">options UFS_ACL</code></dt> + <dd>Access control lists allow the association of fine-grained discretionary + access control information with files and directories. This option + requires the presence of the <code class="Dv">UFS_EXTATTR</code> option, + and it is recommended that <code class="Dv">UFS_EXTATTR_AUTOSTART</code> + is included as well, so that ACLs are enabled atomically upon mounting the + file system.</dd> +</dl> +<p class="Pp">In order to enable support for ACLs, two extended attributes must + be available in the <code class="Dv">EXTATTR_NAMESPACE_SYSTEM</code> + namespace: <span class="Pa">posix1e.acl_access</span>, which holds the + access ACL, and <span class="Pa">posix1e.acl_default</span>, 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 + <a class="Sx" href="#Extended_Attributes">Extended Attributes</a> for more + details.</p> +<div class="Bd Pp Bd-indent Li"> +<pre>mkdir -p /.attribute/system +cd /.attribute/system +extattrctl initattr -p / 388 posix1e.acl_access +extattrctl initattr -p / 388 posix1e.acl_default</pre> +</div> +<p class="Pp">On the next mount of the root file system, the attributes will be + automatically started if <code class="Dv">UFS_EXTATTR_AUTOSTART</code> is + included in the kernel configuration, and ACLs will be enabled.</p> +</section> +<section class="Ss"> +<h2 class="Ss" id="Directory_Hashing"><a class="permalink" href="#Directory_Hashing">Directory + Hashing</a></h2> +<dl class="Bl-tag"> + <dt><code class="Cd">options UFS_DIRHASH</code></dt> + <dd>Implements a hash-based lookup scheme for directories in order to speed up + accesses to very large directories.</dd> +</dl> +</section> +<section class="Ss"> +<h2 class="Ss" id="Extended_Attributes"><a class="permalink" href="#Extended_Attributes">Extended + Attributes</a></h2> +<dl class="Bl-tag"> + <dt><code class="Cd">options UFS_EXTATTR</code></dt> + <dd>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 + <a class="Xr">extattrctl(8)</a>.</dd> + <dt><code class="Cd">options UFS_EXTATTR_AUTOSTART</code></dt> + <dd>If this option is defined, <code class="Nm">ffs</code> will search for a + <span class="Pa">.attribute</span> subdirectory of the file system root + during the mount operation. If found, extended attribute support will be + automatically started for that file system.</dd> +</dl> +</section> +<section class="Ss"> +<h2 class="Ss" id="GEOM-based_Journaling"><a class="permalink" href="#GEOM-based_Journaling">GEOM-based + Journaling</a></h2> +<dl class="Bl-tag"> + <dt><code class="Cd">options UFS_GJOURNAL</code></dt> + <dd>Implements a block level journaling of a UFS file system, which is for + both data and metadata. To enable this, create a + <a class="Xr">gjournal(8)</a> GEOM provider for a block device by using + the following command: + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Nm">gjournal label</code> + <var class="Ar">da0</var></div> + <p class="Pp">In this example, <span class="Pa">/dev/da0</span> is used as + the target block device, and <span class="Pa">/dev/da0.journal</span> is + created. Then create a new file system by using + <a class="Xr">newfs(8)</a> with the block level journaling flag and + mount it:</p> + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Nm">newfs</code> + <code class="Fl">-J</code> <var class="Ar">/dev/da0.journal</var></div> + <div class="Bd Bd-indent"><code class="Nm">mount</code> + <code class="Fl">-o</code> <code class="Cm">async</code> + <var class="Ar">/dev/da0.journal</var> <var class="Ar">/mnt</var></div> + <p class="Pp"><code class="Cm">async</code> option is not mandatory but + recommended for better performance because the journaling guarantees the + consistency of an <code class="Cm">async</code> mount.</p> + <p class="Pp">It is also possible to enable the block level journaling on an + existing file system. To do so, use <a class="Xr">gjournal(8)</a> + utility to label the underlying block device and + <a class="Xr">tunefs(8)</a> utility to enable the block level journaling + flag:</p> + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Nm">gjournal label</code> + <var class="Ar">da0</var></div> + <div class="Bd Bd-indent"><code class="Nm">tunefs</code> + <code class="Fl">-J</code> <code class="Cm">enable</code> + <var class="Ar">/dev/da0.journal</var></div> + <div class="Bd Bd-indent"><code class="Nm">mount</code> + <code class="Fl">-o</code> <code class="Cm">async</code> + <var class="Ar">/dev/da0.journal</var> <var class="Ar">/mnt</var></div> + </dd> +</dl> +</section> +<section class="Ss"> +<h2 class="Ss" id="sysctl_8_MIBs"><a class="permalink" href="#sysctl_8_MIBs"><a class="Xr">sysctl(8)</a> + MIBs</a></h2> +<p class="Pp">The following <a class="Xr">sysctl(8)</a> MIBs are defined for use + with <code class="Nm">ffs</code>:</p> +<dl class="Bl-hang"> + <dt id="vfs.ffs.doasyncfree"><var class="Va">vfs.ffs.doasyncfree</var></dt> + <dd>Asynchronously write out modified i-node and indirect blocks upon + reallocating file system blocks to be contiguous. (Default: 1).</dd> + <dt id="vfs.ffs.doreallocblks"><var class="Va">vfs.ffs.doreallocblks</var></dt> + <dd>Enable support for the rearrangement of blocks to be contiguous. (Default: + 1).</dd> + <dt id="vfs.ffs.prttimechgs"><var class="Va">vfs.ffs.prttimechgs</var></dt> + <dd>Print a console message when timestamps for UFS1 filesystems are found to + be in the future and are changed to be the present time. (Default: + 0).</dd> +</dl> +</section> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">ffs</code> manual page first appeared in + <span class="Ux">FreeBSD 4.5</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">quota(1)</a>, <a class="Xr">acl(3)</a>, + <a class="Xr">extattr(3)</a>, <a class="Xr">edquota(8)</a>, + <a class="Xr">extattrctl(8)</a>, <a class="Xr">fsck_ffs(8)</a>, + <a class="Xr">sysctl(8)</a>, <a class="Xr">tunefs(8)</a></p> +<p class="Pp"><cite class="Rs"><span class="RsA">M. McKusick</span>, + <span class="RsA">W. Joy</span>, <span class="RsA">S. Leffler</span>, and + <span class="RsA">R. Fabry</span>, <span class="RsT">A Fast File System for + UNIX</span>, <i class="RsJ">ACM Transactions on Computer Systems</i>, + <span class="RsN">2</span>, <span class="RsV">3</span>, + <span class="RsP">181-197</span>, <span class="RsD">August + 1984</span>.</cite></p> +<p class="Pp"><cite class="Rs"><span class="RsA">M. McKusick</span>, + <span class="RsT">Soft Updates: A Technique for Eliminating Most Synchronous + Writes in the Fast Filesystem</span>, <i class="RsJ">Proceedings of the + Freenix Track at the 1999 Usenix Annual Technical Conference</i>, + <span class="RsP">71-84</span>, <span class="RsD">June + 2000</span>.</cite></p> +<p class="Pp"><cite class="Rs"><span class="RsA">M. McKusick</span> and + <span class="RsA">J. Roberson</span>, <span class="RsT">Journaled + Soft-updates</span>, <i class="RsJ">BSD Canada Conference 2010 (BSDCan)</i>, + <span class="RsD">May 2010</span>.</cite></p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">February 24, 2026</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |