File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/scripts/checkversion.pl b/scripts/checkversion.pl
new file mode 100755
index 0000000..5e490a8
--- /dev/null
+++ b/scripts/checkversion.pl
@@ -0,0 +1,71 @@
+#! /usr/bin/perl
+#
+# checkversion find uses of LINUX_VERSION_CODE or KERNEL_VERSION
+# without including <linux/version.h>, or cases of
+# including <linux/version.h> that don't need it.
+# Copyright (C) 2003, Randy Dunlap <rdunlap@xenotime.net>
+
+use strict;
+
+$| = 1;
+
+my $debugging;
+
+foreach my $file (@ARGV) {
+    next if $file =~ "include/linux/version\.h";
+    # Open this file.
+    open( my $f, '<', $file )
+      or die "Can't open $file: $!\n";
+
+    # Initialize variables.
+    my ($fInComment, $fInString, $fUseVersion);
+    my $iLinuxVersion = 0;
+
+    while (<$f>) {
+	# Strip comments.
+	$fInComment && (s+^.*?\*/+ +o ? ($fInComment = 0) : next);
+	m+/\*+o && (s+/\*.*?\*/+ +go, (s+/\*.*$+ +o && ($fInComment = 1)));
+
+	# Pick up definitions.
+	if ( m/^\s*#/o ) {
+	    $iLinuxVersion      = $. if m/^\s*#\s*include\s*"linux\/version\.h"/o;
+	}
+
+	# Strip strings.
+	$fInString && (s+^.*?"+ +o ? ($fInString = 0) : next);
+	m+"+o && (s+".*?"+ +go, (s+".*$+ +o && ($fInString = 1)));
+
+	# Pick up definitions.
+	if ( m/^\s*#/o ) {
+	    $iLinuxVersion      = $. if m/^\s*#\s*include\s*<linux\/version\.h>/o;
+	}
+
+	# Look for uses: LINUX_VERSION_CODE, KERNEL_VERSION, UTS_RELEASE
+	if (($_ =~ /LINUX_VERSION_CODE/) || ($_ =~ /\WKERNEL_VERSION/)) {
+	    $fUseVersion = 1;
+            last if $iLinuxVersion;
+        }
+    }
+
+    # Report used version IDs without include?
+    if ($fUseVersion && ! $iLinuxVersion) {
+	print "$file: $.: need linux/version.h\n";
+    }
+
+    # Report superfluous includes.
+    if ($iLinuxVersion && ! $fUseVersion) {
+	print "$file: $iLinuxVersion linux/version.h not needed.\n";
+    }
+
+    # debug: report OK results:
+    if ($debugging) {
+        if ($iLinuxVersion && $fUseVersion) {
+	    print "$file: version use is OK ($iLinuxVersion)\n";
+        }
+        if (! $iLinuxVersion && ! $fUseVersion) {
+	    print "$file: version use is OK (none)\n";
+        }
+    }
+
+    close($f);
+}