#!/bin/bash
# Translate the bits making up a GFP mask
# (c) 2009, Mel Gorman <[email protected]>
# Licensed under the terms of the GNU GPL License version 2
SOURCE=
GFPMASK=none

# Helper function to report failures and exit
die() {
echo ERROR: $@
if [ "$TMPFILE" != "" ]; then
rm -f $TMPFILE
fi
exit -1
}

usage() {
echo "usage: gfp-translate [-h] [ --source DIRECTORY ] gfpmask"
exit 0
}

# Parse command-line arguments
while [ $# -gt 0 ]; do
case $1 in
--source)
SOURCE=$2
shift 2
;;
-h)
usage
;;
--help)
usage
;;
*)
GFPMASK=$1
shift
;;
esac
done

# Guess the kernel source directory if it's not set. Preference is in order of
# o current directory
# o /usr/src/linux
if [ "$SOURCE" = "" ]; then
if [ -r "/usr/src/linux/Makefile" ]; then
SOURCE=/usr/src/linux
fi
if [ -r "`pwd`/Makefile" ]; then
SOURCE=`pwd`
fi
fi

# Confirm that a source directory exists
if [ ! -r "$SOURCE/Makefile" ]; then
die "Could not locate kernel source directory or it is invalid"
fi

# Confirm that a GFP mask has been specified
if [ "$GFPMASK" = "none" ]; then
usage
fi

# Extract GFP flags from the kernel source
TMPFILE=`mktemp -t gfptranslate-XXXXXX` || exit 1
grep -q ___GFP $SOURCE/include/linux/gfp.h
if [ $? -eq 0 ]; then
grep "^#define ___GFP" $SOURCE/include/linux/gfp.h | sed -e 's/u$//' | grep -v GFP_BITS > $TMPFILE
else
grep "^#define __GFP" $SOURCE/include/linux/gfp.h | sed -e 's/(__force gfp_t)//' | sed -e 's/u)/)/' | grep -v GFP_BITS | sed -e 's/)\//) \//' > $TMPFILE
fi

# Parse the flags
IFS="
"
echo Source: $SOURCE
echo Parsing: $GFPMASK
for LINE in `cat $TMPFILE`; do
MASK=`echo $LINE | awk '{print $3}'`
if [ $(($GFPMASK&$MASK)) -ne 0 ]; then
echo $LINE
fi
done

rm -f $TMPFILE
exit 0