1 #!/usr/bin/perl -w
   2 #
   3 # An automated kernel janitor.
   4 # (c) 2001, Dave Jones. <davej@suse.de>, with invaluable
   5 # perl assistance from Rob Andrews <nine@impure.org.uk>
   6 # Various code also inspired from hundreds of other perl scripts.
   7 #
   8 # Additional functionality added by The kerneljanitors.org team :)
   9 #
  10 # Licensed under the terms of the GNU GPL License version 2
  11 #
  12 #
  13 # TODO:
  14 #	  Should reduce some false positives.
  15 #	- Spinlock balancing routine needs to check all return paths
  16 #	  of current subroutine
  17 #	- Spinlock balancing routine can be made more generic to a
  18 #	  "Check that all return paths call $1"
  19 
  20 use strict;
  21 
  22 my @lines;
  23 
  24 foreach my $file (@ARGV) {
  25 	process ($file)
  26 			or warn "Couldn't check file $file: $!";
  27 }
  28 
  29 
  30 sub check_pci_enable_device {
  31 	my $used = shift;
  32 	my $filename = shift;
  33 	my $currentlinenr;
  34 	foreach my $current (@lines) {
  35 		$currentlinenr++;
  36 		if ($current=~/pci_enable_device/) {
  37 			if ($currentlinenr < $used) {
  38 				print "Should be ok, called on line $currentlinenr\n";
  39 				print "$filename:$currentlinenr:$current\n";
  40 			}
  41 		}
  42 	}
  43 }
  44 
  45 
  46 sub check_spinlock {
  47 	my $lock = shift;
  48 	my $filename = shift;
  49 	my $locklinenr = shift;
  50 	my $foundunlock = 0;
  51 	my $currentlinenr;
  52 
  53 # TODO: Start at $locklinenr
  54 
  55 	foreach my $current (@lines) {
  56 		$currentlinenr++;
  57 		if ($current=~/spin_unlock\($lock\)/) {
  58 #			print ("Lock closed on line $currentlinenr\n");
  59 			$foundunlock = 1;
  60 		}
  61 	}
  62 
  63 	return $foundunlock;
  64 }
  65 
  66 
  67 sub process {
  68 	my $filename=shift;
  69 
  70 	return undef unless $filename;
  71 
  72 	open INPUT, $filename
  73 		or return undef;
  74 
  75 	while(!eof INPUT) {
  76 			my $input=<INPUT>;
  77 			chomp $input;
  78 			push @lines, $input;
  79 	}
  80 	close INPUT;		
  81 
  82 #	s!/\*(.*?)\*/!"\n" x (@lines =~ tr/\n//)!esg;
  83 
  84 my $spinlockwarn=0;
  85 my $lookspci=0;
  86 my $linenr=0;
  87 
  88 	foreach my $line (@lines) {
  89 
  90 		$linenr++;
  91 
  92 # For later, we may need to preprocess include files.
  93 # read as: Include them into the array before the current file.
  94 #		if ($line=~/^#include [<"].*?[>"]/i) {
  95 
  96 		if ($line=~/static const char.*__initdata/) {
  97 			print "const & __initdata in string def. Remove const.\n";
  98 			print "$filename:$linenr:$line\n\n";
  99 		}
 100 
 101 		if ($line=~/\(struct netdev_private \*\)/) {
 102 			print "Unnecessary cast.\n";
 103 			print "$filename:$linenr:$line\n\n";
 104 		}
 105 
 106 		if ($line=~/netif_rx/) {
 107 			print "Net drivers should set dev->last_rx immediately after netif_rx\n";
 108 			print "Also make sure the skb isn't referenced after giving it to netif_rx\n";
 109 			print "$filename:$linenr:$line\n\n";
 110 		}
 111 
 112 		if ($line=~/MOD_(INC|DEC)_USE_COUNT/) {
 113 			print "MOD_{INC,DEC}_USE_COUNT are deprecated for 2.6: see the module-init-tools FAQ\n";
 114 			print "$filename:$linenr:$line\n\n";
 115 		}
 116 
 117 		if ($line=~/SET_MODULE_OWNER/) {
 118 			print "SET_MODULE_OWNER is useless for 2.6: see the module-init-tools FAQ\n";
 119 			print "$filename:$linenr:$line\n\n";
 120 		}
 121 
 122 		if ($line=~/sleep_on/) {
 123 			print "Using sleep_on derivative, is racy. consider using wait_event instead\n";
 124 			print "$filename:$linenr:$line\n\n";
 125 		}
 126 
 127 		if ($line=~/check_region/) {
 128 			print "Using check_region, is racy, use just request_region and check for its return.\n";
 129 			print "$filename:$linenr:$line\n\n";
 130 		}
 131 
 132 		if ($line=~/check_mem_region/) {
 133 			print "Using check_mem_region, is racy, use just request_mem_region and check for its return.\n";
 134 			print "$filename:$linenr:$line\n\n";
 135 		}
 136 				
 137 		if ($line=~/pdev-\>irq/) {
 138 			print "Make sure pci_enable_device before reading irq\n";
 139 			check_pci_enable_device($linenr, $filename);
 140 			print "$filename:$linenr:$line\n\n";
 141 		}
 142 
 143 		if (($lookspci==0) and ($line=~/pci_/)) {
 144 			$lookspci=1;
 145 			print "Looks like a PCI driver. Make sure it uses pci_enable_device.\n";
 146 			check_pci_enable_device($linenr, $filename);
 147 			print "$filename:$linenr:$line\n\n";
 148 		}
 149 
 150 		if ($line=~/pdev-\>resource/) {
 151 			print "Make sure pci_enable_device --before-- reading resource\n";
 152 			check_pci_enable_device($linenr, $filename);
 153 			print "$filename:$linenr:$line\n\n";
 154 		}
 155 
 156 		if ($line=~/pcibios_/) {
 157 			print "Uses obsolete pcibios_xxx functions.\n";
 158 			print "$filename:$linenr:$line\n\n";
 159 		}
 160 
 161 		if ($line=~/save_flags_cli/) {
 162 			print "Use local_irq_save instead.\n";
 163 			print "$filename:$linenr:$line\n\n";
 164 		}
 165 
 166 		if ($line=~/isa_{read,write}{b,w,l}/) {
 167 			print "Use ioremap instead of isa_read/write functions.\n";
 168 			print "$filename:$linenr:$line\n\n";
 169 		}
 170 
 171 		if ($line=~/current-\>state/) {
 172 			print "Bad. Should use set_current_state.\n";
 173 			print "$filename:$linenr:$line\n\n";
 174 		}
 175 
 176 
 177 		if ($line=~/loops_per_sec/) {
 178 			print "Warning: loops_per_sec may change..\n";
 179 			print "$filename:$linenr:$line\n\n";
 180 		}
 181 
 182 		if ($line=~/if.*dev-\>mem_start/) {
 183 			if (($line!~/0xffffffff/) or ($line!~/-1/)) {
 184 				print "Should check for 0xffffffff too.\n";
 185 				print "$filename:$linenr:$line\n\n";
 186 			}
 187 		}
 188 
 189 		if (($spinlockwarn==0) and
 190 			(($line=~/cli\(\)/) or
 191 			 ($line=~/sti\(\)/) or
 192 			 ($line=~/lock_kernel/))){
 193 			$spinlockwarn=1;
 194 			print "Consider using spinlocks.\n";
 195 			print "$filename:$linenr:$line\n\n";
 196 		}
 197 
 198 		if ($line=~/return E/) {
 199 			print "Should be return -E ?";
 200 			print "$filename:$linenr:$line\n\n";
 201 		}
 202 
 203 		if ($line=~/spin_lock\((.*)\)/) {
 204 			if (check_spinlock($1, $filename, $line) == 0) {
 205 				print ("Obtained spinlock on line $linenr, but never unlocked.\n\n");
 206 			}
 207 		}
 208 	}
 209 	return 1;
 210 }