1#!/usr/bin/perl -w
2# vi: set sw=4 ts=4:
3# Copyright (c) 2001 David Schleef <ds@schleef.org>
4# Copyright (c) 2001 Erik Andersen <andersen@codepoet.org>
5# Copyright (c) 2001 Stuart Hughes <seh@zee2.com>
6# Copyright (c) 2002 Steven J. Hill <shill@broadcom.com>
7# Copyright (c) 2006 Freescale Semiconductor, Inc <stuarth@freescale.com>
8#
9# History:
10# March 2006: Stuart Hughes <stuarth@freescale.com>.
11#             Significant updates, including implementing the '-F' option
12#             and adding support for 2.6 kernels.
13
14# This program is free software; you can redistribute it and/or modify it
15# under the same terms as Perl itself.
16use Getopt::Long;
17use File::Find;
18use strict;
19
20# Set up some default values
21my $kdir="";
22my $basedir="";
23my $kernel="";
24my $kernelsyms="";
25my $symprefix="";
26my $stdout=0;
27my $verbose=0;
28my $help=0;
29my $nm = $ENV{'NM'} || "nm";
30
31# more globals
32my (@liblist) = ();
33my $exp = {};
34my $dep = {};
35my $mod = {};
36
37my $usage = <<TXT;
38$0 -b basedir { -k <vmlinux> | -F <System.map> } [options]...
39  Where:
40   -h --help          : Show this help screen
41   -b --basedir       : Modules base directory (e.g /lib/modules/<2.x.y>)
42   -k --kernel        : Kernel binary for the target (e.g. vmlinux)
43   -F --kernelsyms    : Kernel symbol file (e.g. System.map)
44   -n --stdout        : Write to stdout instead of <basedir>/modules.dep
45   -v --verbose       : Print out lots of debugging stuff
46   -P --symbol-prefix : Symbol prefix
47TXT
48
49# get command-line options
50GetOptions(
51	"help|h"            => \$help,
52	"basedir|b=s"       => \$basedir,
53	"kernel|k=s"        => \$kernel,
54	"kernelsyms|F=s"    => \$kernelsyms,
55	"stdout|n"          => \$stdout,
56	"verbose|v"         => \$verbose,
57	"symbol-prefix|P=s" => \$symprefix,
58);
59
60die $usage if $help;
61die $usage unless $basedir && ( $kernel || $kernelsyms );
62die "can't use both -k and -F\n\n$usage" if $kernel && $kernelsyms;
63
64# Strip any trailing or multiple slashes from basedir
65$basedir =~ s-(/)\1+-/-g;
66
67# The base directory should contain /lib/modules somewhere
68if($basedir !~ m-/lib/modules-) {
69    warn "WARNING: base directory does not match ..../lib/modules\n";
70}
71
72# if no kernel version is contained in the basedir, try to find one
73if($basedir !~ m-/lib/modules/\d\.\d-) {
74    opendir(BD, $basedir) or die "can't open basedir $basedir : $!\n";
75    foreach ( readdir(BD) ) {
76        next if /^\.\.?$/;
77        next unless -d "$basedir/$_";
78        warn "dir = $_\n" if $verbose;
79        if( /^\d\.\d/ ) {
80            $kdir = $_;
81            warn("Guessed module directory as $basedir/$kdir\n");
82            last;
83        }
84    }
85    closedir(BD);
86    die "Cannot find a kernel version under $basedir\n" unless $kdir;
87    $basedir = "$basedir/$kdir";
88}
89
90# Find the list of .o or .ko files living under $basedir
91warn "**** Locating all modules\n" if $verbose;
92find sub {
93    my $file;
94	if ( -f $_  && ! -d $_ ) {
95		$file = $File::Find::name;
96		if ( $file =~ /\.k?o$/ ) {
97			push(@liblist, $file);
98			warn "$file\n" if $verbose;
99		}
100	}
101}, $basedir;
102warn "**** Finished locating modules\n" if $verbose;
103
104foreach my $obj ( @liblist ){
105    # turn the input file name into a target tag name
106    my ($tgtname) = $obj =~ m-(/lib/modules/.*)$-;
107
108    warn "\nMODULE = $tgtname\n" if $verbose;
109
110    # get a list of symbols
111	my @output=`$nm $obj`;
112
113    build_ref_tables($tgtname, \@output, $exp, $dep);
114}
115
116
117# vmlinux is a special name that is only used to resolve symbols
118my $tgtname = 'vmlinux';
119my @output = $kernelsyms ? `cat $kernelsyms` : `$nm $kernel`;
120warn "\nMODULE = $tgtname\n" if $verbose;
121build_ref_tables($tgtname, \@output, $exp, $dep);
122
123# resolve the dependencies for each module
124# reduce dependencies: remove unresolvable and resolved from vmlinux/System.map
125# remove duplicates
126foreach my $module (keys %$dep) {
127    warn "reducing module: $module\n" if $verbose;
128    $mod->{$module} = {};
129    foreach (@{$dep->{$module}}) {
130        if( $exp->{$_} ) {
131            warn "resolved symbol $_ in file $exp->{$_}\n" if $verbose;
132            next if $exp->{$_} =~ /vmlinux/;
133            $mod->{$module}{$exp->{$_}} = 1;
134        } else {
135            warn "unresolved symbol $_ in file $module\n";
136        }
137    }
138}
139
140# figure out where the output should go
141if ($stdout == 0) {
142    open(STDOUT, ">$basedir/modules.dep")
143                             or die "cannot open $basedir/modules.dep: $!";
144}
145my $kseries = $basedir =~ m,/2\.6\.[^/]*, ? '2.6' : '2.4';
146
147foreach my $module ( keys %$mod ) {
148    if($kseries eq '2.4') {
149	    print "$module:\t";
150	    my @sorted = sort bydep keys %{$mod->{$module}};
151	    print join(" \\\n\t",@sorted);
152	    print "\n\n";
153    } else {
154	    print "$module: ";
155	    my @sorted = sort bydep keys %{$mod->{$module}};
156	    print join(" ",@sorted);
157	    print "\n";
158    }
159}
160
161
162sub build_ref_tables
163{
164    my ($name, $sym_ar, $exp, $dep) = @_;
165
166	my $ksymtab = grep m/ __ksymtab/, @$sym_ar;
167
168    # gather the exported symbols
169	if($ksymtab){
170        # explicitly exported
171        foreach ( @$sym_ar ) {
172            / __ksymtab_(.*)$/ and do {
173                warn "sym = $1\n" if $verbose;
174                $exp->{$1} = $name;
175            };
176        }
177	} else {
178        # exporting all symbols
179        foreach ( @$sym_ar ) {
180            / [ABCDGRST] (.*)$/ and do {
181                warn "syma = $1\n" if $verbose;
182                $exp->{$1} = $name;
183            };
184        }
185	}
186
187    # this takes makes sure modules with no dependencies get listed
188    push @{$dep->{$name}}, $symprefix . 'printk' unless $name eq 'vmlinux';
189
190    # gather the unresolved symbols
191    foreach ( @$sym_ar ) {
192        !/ __this_module/ && / U (.*)$/ and do {
193            warn "und = $1\n" if $verbose;
194            push @{$dep->{$name}}, $1;
195        };
196    }
197}
198
199sub bydep
200{
201    foreach my $f ( keys %{$mod->{$b}} ) {
202        if($f eq $a) {
203            return 1;
204        }
205    }
206    return -1;
207}
208
209
210
211__END__
212
213=head1 NAME
214
215depmod.pl - a cross platform script to generate kernel module
216dependency lists (modules.conf) which can then be used by modprobe
217on the target platform.
218
219It supports Linux 2.4 and 2.6 styles of modules.conf (auto-detected)
220
221=head1 SYNOPSIS
222
223depmod.pl [OPTION]... [basedir]...
224
225Example:
226
227	depmod.pl -F linux/System.map -b target/lib/modules/2.6.11
228
229=head1 DESCRIPTION
230
231The purpose of this script is to automagically generate a list of of kernel
232module dependencies.  This script produces dependency lists that should be
233identical to the depmod program from the modutils package.  Unlike the depmod
234binary, however, depmod.pl is designed to be run on your host system, not
235on your target system.
236
237This script was written by David Schleef <ds@schleef.org> to be used in
238conjunction with the BusyBox modprobe applet.
239
240=head1 OPTIONS
241
242=over 4
243
244=item B<-h --help>
245
246This displays the help message.
247
248=item B<-b --basedir>
249
250The base directory uner which the target's modules will be found.  This
251defaults to the /lib/modules directory.
252
253If you don't specify the kernel version, this script will search for
254one under the specified based directory and use the first thing that
255looks like a kernel version.
256
257=item B<-k --kernel>
258
259Kernel binary for the target (vmlinux).  You must either supply a kernel binary
260or a kernel symbol file (using the -F option).
261
262=item B<-F --kernelsyms>
263
264Kernel symbol file for the target (System.map).
265
266=item B<-n --stdout>
267
268Write to stdout instead of modules.dep
269kernel binary for the target (using the -k option).
270
271=item B<--verbose>
272
273Verbose (debug) output
274
275=back
276
277=head1 COPYRIGHT AND LICENSE
278
279 Copyright (c) 2001 David Schleef <ds@schleef.org>
280 Copyright (c) 2001 Erik Andersen <andersen@codepoet.org>
281 Copyright (c) 2001 Stuart Hughes <seh@zee2.com>
282 Copyright (c) 2002 Steven J. Hill <shill@broadcom.com>
283 Copyright (c) 2006 Freescale Semiconductor, Inc <stuarth@freescale.com>
284
285This program is free software; you can redistribute it and/or modify it
286under the same terms as Perl itself.
287
288=head1 AUTHOR
289
290David Schleef <ds@schleef.org>
291
292=cut
293