1 files changed, 65 insertions, 0 deletions

diff --git a/Documentation/filesystems/devfs/boot-options b/Documentation/filesystems/devfs/boot-options
new file mode 100644
index 000000000000..df3d33b03e0a
--- /dev/null
+++ b/Documentation/filesystems/devfs/boot-options
@@ -0,0 +1,65 @@
+/* -*- auto-fill -*-                                                         */
+
+                Device File System (devfs) Boot Options
+
+                Richard Gooch <rgooch@atnf.csiro.au>
+
+                              18-AUG-2001
+
+
+When CONFIG_DEVFS_DEBUG is enabled, you can pass several boot options
+to the kernel to debug devfs. The boot options are prefixed by
+"devfs=", and are separated by commas. Spaces are not allowed. The
+syntax looks like this:
+
+devfs=<option1>,<option2>,<option3>
+
+and so on. For example, if you wanted to turn on debugging for module
+load requests and device registration, you would do:
+
+devfs=dmod,dreg
+
+You may prefix "no" to any option. This will invert the option.
+
+
+Debugging Options
+=================
+
+These requires CONFIG_DEVFS_DEBUG to be enabled.
+Note that all debugging options have 'd' as the first character. By
+default all options are off. All debugging output is sent to the
+kernel logs. The debugging options do not take effect until the devfs
+version message appears (just prior to the root filesystem being
+mounted).
+
+These are the options:
+
+dmod            print module load requests to <request_module>
+
+dreg            print device register requests to <devfs_register>
+
+dunreg          print device unregister requests to <devfs_unregister>
+
+dchange         print device change requests to <devfs_set_flags>
+
+dilookup        print inode lookup requests
+
+diget           print VFS inode allocations
+
+diunlink        print inode unlinks
+
+dichange        print inode changes
+
+dimknod         print calls to mknod(2)
+
+dall            some debugging turned on
+
+
+Other Options
+=============
+
+These control the default behaviour of devfs. The options are:
+
+mount           mount devfs onto /dev at boot time
+
+only            disable non-devfs device nodes for devfs-capable drivers