1#!/bin/bash
2# SPDX-License-Identifier: GPL-2.0-only
3# Translate the bits making up a GFP mask
4# (c) 2009, Mel Gorman <mel@csn.ul.ie>
5SOURCE=
6GFPMASK=none
7
8# Helper function to report failures and exit
9die() {
10	echo ERROR: $@
11	if [ "$TMPFILE" != "" ]; then
12		rm -f $TMPFILE
13	fi
14	exit -1
15}
16
17usage() {
18	echo "usage: gfp-translate [-h] [ --source DIRECTORY ] gfpmask"
19	exit 0
20}
21
22# Parse command-line arguments
23while [ $# -gt 0 ]; do
24	case $1 in
25		--source)
26			SOURCE=$2
27			shift 2
28			;;
29		-h)
30			usage
31			;;
32		--help)
33			usage
34			;;
35		*)
36			GFPMASK=$1
37			shift
38			;;
39	esac
40done
41
42# Guess the kernel source directory if it's not set. Preference is in order of
43# o current directory
44# o /usr/src/linux
45if [ "$SOURCE" = "" ]; then
46	if [ -r "/usr/src/linux/Makefile" ]; then
47		SOURCE=/usr/src/linux
48	fi
49	if [ -r "`pwd`/Makefile" ]; then
50		SOURCE=`pwd`
51	fi
52fi
53
54# Confirm that a source directory exists
55if [ ! -r "$SOURCE/Makefile" ]; then
56	die "Could not locate kernel source directory or it is invalid"
57fi
58
59# Confirm that a GFP mask has been specified
60if [ "$GFPMASK" = "none" ]; then
61	usage
62fi
63
64# Extract GFP flags from the kernel source
65TMPFILE=`mktemp -t gfptranslate-XXXXXX.c` || exit 1
66
67echo Source: $SOURCE
68echo Parsing: $GFPMASK
69
70(
71    cat <<EOF
72#include <stdint.h>
73#include <stdio.h>
74
75// Try to fool compiler.h into not including extra stuff
76#define __ASSEMBLY__	1
77
78#include <generated/autoconf.h>
79#include <linux/gfp_types.h>
80
81static const char *masks[] = {
82EOF
83
84    sed -nEe 's/^[[:space:]]+(___GFP_.*)_BIT,.*$/\1/p' $SOURCE/include/linux/gfp_types.h |
85	while read b; do
86	    cat <<EOF
87#if defined($b) && ($b > 0)
88	[${b}_BIT]	= "$b",
89#endif
90EOF
91	done
92
93    cat <<EOF
94};
95
96int main(int argc, char *argv[])
97{
98	unsigned long long mask = $GFPMASK;
99
100	for (int i = 0; i < sizeof(mask) * 8; i++) {
101		unsigned long long bit = 1ULL << i;
102		if (mask & bit)
103			printf("\t%-25s0x%llx\n",
104			       (i < ___GFP_LAST_BIT && masks[i]) ?
105					masks[i] : "*** INVALID ***",
106			       bit);
107	}
108
109	return 0;
110}
111EOF
112) > $TMPFILE
113
114${CC:-gcc} -Wall -o ${TMPFILE}.bin -I $SOURCE/include $TMPFILE && ${TMPFILE}.bin
115
116rm -f $TMPFILE ${TMPFILE}.bin
117
118exit 0
119