|
|
@@ -1,213 +1,237 @@
|
|
|
<?xml version="1.0" encoding="ISO-8859-1"?>
|
|
|
-<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN" "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
|
|
|
+<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
|
|
|
+ "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd" [
|
|
|
<!ENTITY % general-entities SYSTEM "../general.ent">
|
|
|
%general-entities;
|
|
|
]>
|
|
|
+
|
|
|
<sect1 id="ch-scripts-udev">
|
|
|
-<title>Device and Module Handling on an LFS System</title>
|
|
|
-<?dbhtml filename="udev.html"?>
|
|
|
-
|
|
|
-<indexterm zone="ch-scripts-udev">
|
|
|
-<primary sortas="a-Udev">Udev</primary>
|
|
|
-<secondary>usage</secondary></indexterm>
|
|
|
-
|
|
|
-<para>In <xref linkend="chapter-building-system"/>, we installed the Udev
|
|
|
-package. Before we go into the details regarding how this works,
|
|
|
-a brief history of previous methods of handling devices is in
|
|
|
-order.</para>
|
|
|
-
|
|
|
-<para>Linux systems in general traditionally use a static device creation
|
|
|
-method, whereby a great many device nodes are created under <filename
|
|
|
-class="directory">/dev</filename> (sometimes literally thousands of nodes),
|
|
|
-regardless of whether the corresponding hardware devices actually exist. This is
|
|
|
-typically done via a <command>MAKEDEV</command> script, which contains a number
|
|
|
-of calls to the <command>mknod</command> program with the relevant major and
|
|
|
-minor device numbers for every possible device that might exist in the world.
|
|
|
-Using the Udev method, only those devices which are detected by the kernel get
|
|
|
-device nodes created for them. Because these device nodes will be created each
|
|
|
-time the system boots, they will be stored on a <systemitem
|
|
|
-class="filesystem">tmpfs</systemitem> file system (a virtual file system that
|
|
|
-resides entirely in system memory). Device nodes do not require much space, so
|
|
|
-the memory that is used is negligible.</para>
|
|
|
-
|
|
|
-<sect2>
|
|
|
-<title>History</title>
|
|
|
-
|
|
|
-<para>In February 2000, a new filesystem called <systemitem
|
|
|
-class="filesystem">devfs</systemitem> was merged into the 2.3.46
|
|
|
-kernel and was made available during the 2.4 series of
|
|
|
-stable kernels. Although it was present in the kernel source itself,
|
|
|
-this method of creating devices dynamically never received
|
|
|
-overwhelming support from the core kernel developers.</para>
|
|
|
-
|
|
|
-<para>The main problem with the approach adopted by <systemitem
|
|
|
-class="filesystem">devfs</systemitem> was the way it handled
|
|
|
-device detection, creation, and naming. The latter issue, that of
|
|
|
-device node naming, was perhaps the most critical. It is generally
|
|
|
-accepted that if device names are allowed to be configurable, then
|
|
|
-the device naming policy should be up to a system administrator, not
|
|
|
-imposed on them by any particular developer(s). The <systemitem
|
|
|
-class="filesystem">devfs</systemitem> file system also suffers from race
|
|
|
-conditions that are inherent in its design and cannot be fixed
|
|
|
-without a substantial revision to the kernel. It has also been marked
|
|
|
-as deprecated due to a lack of recent maintenance.</para>
|
|
|
-
|
|
|
-<para>With the development of the unstable 2.5 kernel tree, later released as
|
|
|
-the 2.6 series of stable kernels, a new virtual filesystem called <systemitem
|
|
|
-class="filesystem">sysfs</systemitem> came to be. The job of <systemitem
|
|
|
-class="filesystem">sysfs</systemitem> is to export a view of the system's
|
|
|
-hardrware configuration to userspace processes. With this userspace-visible
|
|
|
-representation, the possibility of seeing a userspace replacement for
|
|
|
-<systemitem class="filesystem">devfs</systemitem> became much more
|
|
|
-realistic.</para>
|
|
|
-
|
|
|
-</sect2>
|
|
|
-
|
|
|
-<sect2>
|
|
|
-<title>Udev Implementation</title>
|
|
|
-
|
|
|
-<para>The <systemitem class="filesystem">sysfs</systemitem> filesystem was
|
|
|
-mentioned briefly above. One may wonder how <systemitem
|
|
|
-class="filesystem">sysfs</systemitem> knows about the devices present on a
|
|
|
-system and what device numbers should be used for them. Drivers that have been
|
|
|
-compiled into the kernel directly register their objects with <systemitem
|
|
|
-class="filesystem">sysfs</systemitem> as they are detected by the kernel. For
|
|
|
-drivers compiled as modules, this registration will happen when the module is
|
|
|
-loaded. Once the <systemitem class="filesystem">sysfs</systemitem> filesystem is
|
|
|
-mounted (on <filename class="directory">/sys</filename>), data which the
|
|
|
-built-in drivers registered with <systemitem
|
|
|
-class="filesystem">sysfs</systemitem> are available to userspace processes and
|
|
|
-to <command>udev</command> for device node creation.</para>
|
|
|
-
|
|
|
-<para>The <command>S10udev</command> initscript takes care of creating these
|
|
|
-device nodes when Linux is booted. This script starts by registering
|
|
|
-<command>/sbin/udevsend</command> as a hotplug event handler. Hotplug events
|
|
|
-(discussed below) are not usually generated during this stage, but
|
|
|
-<command>udev</command> is registered just in case they do occur. The
|
|
|
-<command>udevstart</command> program then walks through the <systemitem
|
|
|
-class="filesystem">/sys</systemitem> filesystem and creates devices under
|
|
|
-<filename class="directory">/dev</filename> that match the descriptions. For
|
|
|
-example, <filename>/sys/class/tty/vcs/dev</filename> contains the string
|
|
|
-<quote>7:0</quote> This string is used by <command>udevstart</command> to create
|
|
|
-<filename>/dev/vcs</filename> with major number <emphasis>7</emphasis> and minor
|
|
|
-<emphasis>0</emphasis>. The names and permissions of the nodes created under
|
|
|
-the <filename class="directory">/dev</filename> directory are configured
|
|
|
-according to the rules specified in the files within the <filename
|
|
|
-class="directory">/etc/udev/rules.d/</filename> directory. These are numbered in
|
|
|
-a similar fashion to the LFS-Bootscripts package. If <command>udev</command>
|
|
|
-can't find a rule for the device it is creating, it will default permissions to
|
|
|
-<emphasis>660</emphasis> and ownership to <emphasis>root:root</emphasis>.</para>
|
|
|
-
|
|
|
-<para>Once the above stage is complete, all devices that were already present
|
|
|
-and have compiled-in drivers will be available for use. This leads us to the
|
|
|
-devices that have modular drivers.</para>
|
|
|
-
|
|
|
-<para>Earlier, we mentioned the concept of a <quote>hotplug event
|
|
|
-handler.</quote> When a new device connection is detected by the kernel, the
|
|
|
-kernel will generate a hotplug event and look at the file
|
|
|
-<filename>/proc/sys/kernel/hotplug</filename> to determine the userspace program
|
|
|
-that handles the device's connection. The <command>udev</command> bootscript
|
|
|
-registered <command>udevsend</command> as this handler. When these hotplug
|
|
|
-events are generated, the kernel will tell <command>udev</command> to check the
|
|
|
-<filename class="directory">/sys</filename> filesystem for the information
|
|
|
-pertaining to this new device and create the <filename
|
|
|
-class="directory">/dev</filename> entry for it.</para>
|
|
|
-
|
|
|
-<para>This brings us to one problem that exists with <command>udev</command>,
|
|
|
-and likewise with <systemitem class="filesystem">devfs</systemitem> before it.
|
|
|
-It is commonly referred to as the <quote>chicken and egg</quote> problem. Most
|
|
|
-Linux distributions handle loading modules via entries in
|
|
|
-<filename>/etc/modules.conf</filename>. Access to a device node causes the
|
|
|
-appropriate kernel module to load. With <command>udev</command>, this method
|
|
|
-will not work because the device node does not exist until the module is loaded.
|
|
|
-To solve this, the <command>S05modules</command> bootscript was added to the
|
|
|
-LFS-Bootscripts package, along with the
|
|
|
-<filename>/etc/sysconfig/modules</filename> file. By adding module names to the
|
|
|
-<filename>modules</filename> file, these modules will be loaded when the
|
|
|
-computer starts up. This allows <command>udev</command> to detect the devices
|
|
|
-and create the appropriate device nodes.</para>
|
|
|
-
|
|
|
-<para>Note that on slower machines or for drivers that create a lot
|
|
|
-of device nodes, the process of creating devices may take a few
|
|
|
-seconds to complete. This means that some device nodes may not be
|
|
|
-immediately accessible.</para>
|
|
|
-</sect2>
|
|
|
-
|
|
|
-<sect2>
|
|
|
-<title>Handling Hotpluggable/Dynamic Devices</title>
|
|
|
-
|
|
|
-<para>When you plug in a device, such as a Universal Serial Bus (USB) MP3 player, the kernel
|
|
|
-recognizes that the device is now connected and generates a hotplug
|
|
|
-event. If the driver is already loaded (either because it was compiled
|
|
|
-into the kernel or because it was loaded via the
|
|
|
-<command>S05modules</command> bootscript), <command>udev</command> will
|
|
|
-be called upon to create the relevant device node(s) according to the
|
|
|
-<systemitem class="filesystem">sysfs</systemitem> data available in
|
|
|
-<filename class="directory">/sys</filename>.</para>
|
|
|
-
|
|
|
-<para>If the driver for the just plugged in device is available as a module but
|
|
|
-currently unloaded, the Hotplug package will load the appropriate module
|
|
|
-and make this device available by creating the device node(s) for it.</para>
|
|
|
-</sect2>
|
|
|
-
|
|
|
-<sect2>
|
|
|
-<title>Problems with Creating Devices</title>
|
|
|
-
|
|
|
-<para>There are a few known problems when it comes to automatically creating
|
|
|
-device nodes:</para>
|
|
|
-
|
|
|
-<para>1) A kernel driver may not export its data to <systemitem
|
|
|
-class="filesystem">sysfs</systemitem>.</para>
|
|
|
-
|
|
|
-<para>This is most common with third party drivers from outside the kernel tree.
|
|
|
-Udev will be unable to automatically create device nodes for such drivers. Use
|
|
|
-the <filename>/etc/sysconfig/createfiles</filename> configuration file to
|
|
|
-manually create the devices. Consult the <filename>devices.txt</filename> file
|
|
|
-inside the kernel documentation or the documentation for that driver to find the
|
|
|
-proper major/minor numbers.</para>
|
|
|
-
|
|
|
-<para>2) A non-hardware device is required. This is most common with
|
|
|
-the Advanced Linux Sound Architecture (ALSA) project's Open Sound
|
|
|
-System (OSS) compatibility module. These types of devices can be
|
|
|
-handled in one of two ways:</para>
|
|
|
-
|
|
|
-<itemizedlist>
|
|
|
-
|
|
|
-<listitem><para>Adding the module names to
|
|
|
-<filename>/etc/sysconfig/modules</filename></para></listitem>
|
|
|
-<listitem><para>Using an
|
|
|
-<quote>install</quote> line in
|
|
|
-<filename>/etc/modprobe.conf</filename>. This tells the
|
|
|
-<command>modprobe</command> command <quote>when loading this module,
|
|
|
-also load this other module, at the same time.</quote> For example:</para>
|
|
|
+ <?dbhtml filename="udev.html"?>
|
|
|
+
|
|
|
+ <title>Device and Module Handling on an LFS System</title>
|
|
|
+
|
|
|
+ <indexterm zone="ch-scripts-udev">
|
|
|
+ <primary sortas="a-Udev">Udev</primary>
|
|
|
+ <secondary>usage</secondary>
|
|
|
+ </indexterm>
|
|
|
+
|
|
|
+ <para>In <xref linkend="chapter-building-system"/>, we installed the Udev
|
|
|
+ package. Before we go into the details regarding how this works,
|
|
|
+ a brief history of previous methods of handling devices is in
|
|
|
+ order.</para>
|
|
|
+
|
|
|
+ <para>Linux systems in general traditionally use a static device creation
|
|
|
+ method, whereby a great many device nodes are created under <filename
|
|
|
+ class="directory">/dev</filename> (sometimes literally thousands of nodes),
|
|
|
+ regardless of whether the corresponding hardware devices actually exist. This is
|
|
|
+ typically done via a <command>MAKEDEV</command> script, which contains a number
|
|
|
+ of calls to the <command>mknod</command> program with the relevant major and
|
|
|
+ minor device numbers for every possible device that might exist in the world.
|
|
|
+ Using the Udev method, only those devices which are detected by the kernel get
|
|
|
+ device nodes created for them. Because these device nodes will be created each
|
|
|
+ time the system boots, they will be stored on a <systemitem
|
|
|
+ class="filesystem">tmpfs</systemitem> file system (a virtual file system that
|
|
|
+ resides entirely in system memory). Device nodes do not require much space, so
|
|
|
+ the memory that is used is negligible.</para>
|
|
|
+
|
|
|
+ <sect2>
|
|
|
+ <title>History</title>
|
|
|
+
|
|
|
+ <para>In February 2000, a new filesystem called <systemitem
|
|
|
+ class="filesystem">devfs</systemitem> was merged into the 2.3.46 kernel
|
|
|
+ and was made available during the 2.4 series of stable kernels. Although
|
|
|
+ it was present in the kernel source itself, this method of creating devices
|
|
|
+ dynamically never received overwhelming support from the core kernel
|
|
|
+ developers.</para>
|
|
|
+
|
|
|
+ <para>The main problem with the approach adopted by <systemitem
|
|
|
+ class="filesystem">devfs</systemitem> was the way it handled device
|
|
|
+ detection, creation, and naming. The latter issue, that of device node
|
|
|
+ naming, was perhaps the most critical. It is generally accepted that if
|
|
|
+ device names are allowed to be configurable, then the device naming policy
|
|
|
+ should be up to a system administrator, not imposed on them by any
|
|
|
+ particular developer(s). The <systemitem class="filesystem">devfs</systemitem>
|
|
|
+ file system also suffers from race conditions that are inherent in its design
|
|
|
+ and cannot be fixed without a substantial revision to the kernel. It has also
|
|
|
+ been marked as deprecated due to a lack of recent maintenance.</para>
|
|
|
+
|
|
|
+ <para>With the development of the unstable 2.5 kernel tree, later released as
|
|
|
+ the 2.6 series of stable kernels, a new virtual filesystem called <systemitem
|
|
|
+ class="filesystem">sysfs</systemitem> came to be. The job of <systemitem
|
|
|
+ class="filesystem">sysfs</systemitem> is to export a view of the system's
|
|
|
+ hardrware configuration to userspace processes. With this userspace-visible
|
|
|
+ representation, the possibility of seeing a userspace replacement for
|
|
|
+ <systemitem class="filesystem">devfs</systemitem> became much more
|
|
|
+ realistic.</para>
|
|
|
+
|
|
|
+ </sect2>
|
|
|
+
|
|
|
+ <sect2>
|
|
|
+ <title>Udev Implementation</title>
|
|
|
+
|
|
|
+ <para>The <systemitem class="filesystem">sysfs</systemitem> filesystem was
|
|
|
+ mentioned briefly above. One may wonder how <systemitem
|
|
|
+ class="filesystem">sysfs</systemitem> knows about the devices present on
|
|
|
+ a system and what device numbers should be used for them. Drivers that have
|
|
|
+ been compiled into the kernel directly register their objects with
|
|
|
+ <systemitem class="filesystem">sysfs</systemitem> as they are detected by
|
|
|
+ the kernel. For drivers compiled as modules, this registration will happen
|
|
|
+ when the module is loaded. Once the <systemitem
|
|
|
+ class="filesystem">sysfs</systemitem> filesystem is mounted (on <filename
|
|
|
+ class="directory">/sys</filename>), data which the built-in drivers
|
|
|
+ registered with <systemitem class="filesystem">sysfs</systemitem> are
|
|
|
+ available to userspace processes and to <command>udev</command> for device
|
|
|
+ node creation.</para>
|
|
|
+
|
|
|
+ <para>The <command>S10udev</command> initscript takes care of creating
|
|
|
+ these device nodes when Linux is booted. This script starts by registering
|
|
|
+ <command>/sbin/udevsend</command> as a hotplug event handler. Hotplug events
|
|
|
+ (discussed below) are not usually generated during this stage, but
|
|
|
+ <command>udev</command> is registered just in case they do occur. The
|
|
|
+ <command>udevstart</command> program then walks through the <systemitem
|
|
|
+ class="filesystem">/sys</systemitem> filesystem and creates devices under
|
|
|
+ <filename class="directory">/dev</filename> that match the descriptions.
|
|
|
+ For example, <filename>/sys/class/tty/vcs/dev</filename> contains the
|
|
|
+ string <quote>7:0</quote> This string is used by <command>udevstart</command>
|
|
|
+ to create <filename>/dev/vcs</filename> with major number
|
|
|
+ <emphasis>7</emphasis> and minor <emphasis>0</emphasis>. The names and
|
|
|
+ permissions of the nodes created under the <filename
|
|
|
+ class="directory">/dev</filename> directory are configured according to the
|
|
|
+ rules specified in the files within the <filename
|
|
|
+ class="directory">/etc/udev/rules.d/</filename> directory. These are
|
|
|
+ numbered in a similar fashion to the LFS-Bootscripts package. If
|
|
|
+ <command>udev</command> can't find a rule for the device it is creating,
|
|
|
+ it will default permissions to <emphasis>660</emphasis> and ownership to
|
|
|
+ <emphasis>root:root</emphasis>.</para>
|
|
|
+
|
|
|
+ <para>Once the above stage is complete, all devices that were already present
|
|
|
+ and have compiled-in drivers will be available for use. This leads us to the
|
|
|
+ devices that have modular drivers.</para>
|
|
|
+
|
|
|
+ <para>Earlier, we mentioned the concept of a <quote>hotplug event
|
|
|
+ handler.</quote> When a new device connection is detected by the kernel,
|
|
|
+ the kernel will generate a hotplug event and look at the file
|
|
|
+ <filename>/proc/sys/kernel/hotplug</filename> to determine the userspace
|
|
|
+ program that handles the device's connection. The <command>udev</command>
|
|
|
+ bootscript registered <command>udevsend</command> as this handler. When
|
|
|
+ these hotplug events are generated, the kernel will tell
|
|
|
+ <command>udev</command> to check the <filename
|
|
|
+ class="directory">/sys</filename> filesystem for the information pertaining
|
|
|
+ to this new device and create the <filename class="directory">/dev</filename>
|
|
|
+ entry for it.</para>
|
|
|
+
|
|
|
+ <para>This brings us to one problem that exists with <command>udev</command>,
|
|
|
+ and likewise with <systemitem class="filesystem">devfs</systemitem> before it.
|
|
|
+ It is commonly referred to as the <quote>chicken and egg</quote> problem. Most
|
|
|
+ Linux distributions handle loading modules via entries in
|
|
|
+ <filename>/etc/modules.conf</filename>. Access to a device node causes the
|
|
|
+ appropriate kernel module to load. With <command>udev</command>, this method
|
|
|
+ will not work because the device node does not exist until the module is loaded.
|
|
|
+ To solve this, the <command>S05modules</command> bootscript was added to the
|
|
|
+ LFS-Bootscripts package, along with the
|
|
|
+ <filename>/etc/sysconfig/modules</filename> file. By adding module names to the
|
|
|
+ <filename>modules</filename> file, these modules will be loaded when the
|
|
|
+ computer starts up. This allows <command>udev</command> to detect the devices
|
|
|
+ and create the appropriate device nodes.</para>
|
|
|
+
|
|
|
+ <para>Note that on slower machines or for drivers that create a lot of device
|
|
|
+ nodes, the process of creating devices may take a few seconds to complete.
|
|
|
+ This means that some device nodes may not be immediately accessible.</para>
|
|
|
+
|
|
|
+ </sect2>
|
|
|
+
|
|
|
+ <sect2>
|
|
|
+ <title>Handling Hotpluggable/Dynamic Devices</title>
|
|
|
+
|
|
|
+ <para>When you plug in a device, such as a Universal Serial Bus (USB) MP3
|
|
|
+ player, the kernel recognizes that the device is now connected and generates
|
|
|
+ a hotplug event. If the driver is already loaded (either because it was
|
|
|
+ compiled into the kernel or because it was loaded via the
|
|
|
+ <command>S05modules</command> bootscript), <command>udev</command> will be
|
|
|
+ called upon to create the relevant device node(s) according to the
|
|
|
+ <systemitem class="filesystem">sysfs</systemitem> data available in
|
|
|
+ <filename class="directory">/sys</filename>.</para>
|
|
|
+
|
|
|
+ <para>If the driver for the just plugged in device is available as a module but
|
|
|
+ currently unloaded, the Hotplug package will load the appropriate module
|
|
|
+ and make this device available by creating the device node(s) for it.</para>
|
|
|
+
|
|
|
+ </sect2>
|
|
|
+
|
|
|
+ <sect2>
|
|
|
+ <title>Problems with Creating Devices</title>
|
|
|
+
|
|
|
+ <para>There are a few known problems when it comes to automatically creating
|
|
|
+ device nodes:</para>
|
|
|
+
|
|
|
+ <para>1) A kernel driver may not export its data to <systemitem
|
|
|
+ class="filesystem">sysfs</systemitem>.</para>
|
|
|
+
|
|
|
+ <para>This is most common with third party drivers from outside the kernel
|
|
|
+ tree. Udev will be unable to automatically create device nodes for such
|
|
|
+ drivers. Use the <filename>/etc/sysconfig/createfiles</filename>
|
|
|
+ configuration file to manually create the devices. Consult the
|
|
|
+ <filename>devices.txt</filename> file inside the kernel documentation or
|
|
|
+ the documentation for that driver to find the proper major/minor
|
|
|
+ numbers.</para>
|
|
|
+
|
|
|
+ <para>2) A non-hardware device is required. This is most common with
|
|
|
+ the Advanced Linux Sound Architecture (ALSA) project's Open Sound
|
|
|
+ System (OSS) compatibility module. These types of devices can be
|
|
|
+ handled in one of two ways:</para>
|
|
|
+
|
|
|
+ <itemizedlist>
|
|
|
+
|
|
|
+ <listitem>
|
|
|
+ <para>Adding the module names to
|
|
|
+ <filename>/etc/sysconfig/modules</filename></para>
|
|
|
+ </listitem>
|
|
|
+
|
|
|
+ <listitem>
|
|
|
+ <para>Using an <quote>install</quote> line in
|
|
|
+ <filename>/etc/modprobe.conf</filename>. This tells the
|
|
|
+ <command>modprobe</command> command <quote>when loading this module,
|
|
|
+ also load this other module, at the same time.</quote>
|
|
|
+ For example:</para>
|
|
|
|
|
|
<screen role="nodump"><userinput>install snd-pcm modprobe -i snd-pcm ; modprobe \
|
|
|
snd-pcm-oss ; true</userinput></screen>
|
|
|
|
|
|
-<para>This will cause the system to load both the
|
|
|
-<emphasis>snd-pcm</emphasis> and <emphasis>snd-pcm-oss</emphasis>
|
|
|
-modules when any request is made to load the driver
|
|
|
-<emphasis>snd-pcm</emphasis>.</para></listitem>
|
|
|
-</itemizedlist>
|
|
|
-</sect2>
|
|
|
+ <para>This will cause the system to load both the
|
|
|
+ <emphasis>snd-pcm</emphasis> and <emphasis>snd-pcm-oss</emphasis>
|
|
|
+ modules when any request is made to load the driver
|
|
|
+ <emphasis>snd-pcm</emphasis>.</para>
|
|
|
+ </listitem>
|
|
|
|
|
|
-<sect2>
|
|
|
-<title>Useful Reading</title>
|
|
|
+ </itemizedlist>
|
|
|
|
|
|
-<para>Additional helpful documentation is available at the following
|
|
|
-sites:</para>
|
|
|
+ </sect2>
|
|
|
|
|
|
-<itemizedlist>
|
|
|
-<listitem><para>A Userspace Implementation of <systemitem class="filesystem">devfs</systemitem>
|
|
|
-<ulink url="http://www.kroah.com/linux/talks/ols_2003_udev_paper/Reprint-Kroah-Hartman-OLS2003.pdf"/></para></listitem>
|
|
|
+ <sect2>
|
|
|
+ <title>Useful Reading</title>
|
|
|
|
|
|
-<listitem><para>udev FAQ
|
|
|
-<ulink url="http://www.kernel.org/pub/linux/utils/kernel/hotplug/udev-FAQ"/></para></listitem>
|
|
|
+ <para>Additional helpful documentation is available at the following
|
|
|
+ sites:</para>
|
|
|
|
|
|
-<listitem><para>The Linux Kernel Driver Model
|
|
|
-<ulink url="http://public.planetmirror.com/pub/lca/2003/proceedings/papers/Patrick_Mochel/Patrick_Mochel.pdf"/></para></listitem>
|
|
|
-</itemizedlist>
|
|
|
-</sect2>
|
|
|
+ <itemizedlist>
|
|
|
|
|
|
-</sect1>
|
|
|
+ <listitem>
|
|
|
+ <para>A Userspace Implementation of <systemitem class="filesystem">devfs</systemitem>
|
|
|
+ <ulink url="http://www.kroah.com/linux/talks/ols_2003_udev_paper/Reprint-Kroah-Hartman-OLS2003.pdf"/></para>
|
|
|
+ </listitem>
|
|
|
+
|
|
|
+ <listitem>
|
|
|
+ <para>udev FAQ
|
|
|
+ <ulink url="http://www.kernel.org/pub/linux/utils/kernel/hotplug/udev-FAQ"/></para>
|
|
|
+ </listitem>
|
|
|
+
|
|
|
+ <listitem>
|
|
|
+ <para>The Linux Kernel Driver Model
|
|
|
+ <ulink url="http://public.planetmirror.com/pub/lca/2003/proceedings/papers/Patrick_Mochel/Patrick_Mochel.pdf"/></para>
|
|
|
+ </listitem>
|
|
|
|
|
|
+ </itemizedlist>
|
|
|
+
|
|
|
+ </sect2>
|
|
|
+
|
|
|
+</sect1>
|
Manuel Canales Esparcia