#!/bin/bash

#

# Version for APM 

#

# start or stop laptop_mode, best run by a power management daemon when

# ac gets connected/disconnected from a laptop

#

#

# Contributors to this script:   Kiko Piris

#				 Bart Samwel

#				 Micha Feigin

#				 Andrew Morton

#				 Herve Eychenne

#				 Dax Kelson

#

# Original Linux 2.4 version by: Jens Axboe

#############################################################################

# Source config

if [ -f /etc/sysconfig/apmd ] ; then

	. /etc/sysconfig/apmd

fi

# Don't raise an error if the config file is incomplete

# set defaults instead:

# Maximum time, in seconds, of hard drive spindown time that you are

# comfortable with. Worst case, it's possible that you could lose this

# amount of work if your battery fails you while in laptop mode.

MAX_AGE=${MAX_AGE:-'600'}

# Read-ahead, in kilobytes

READAHEAD=${READAHEAD:-'4096'}

# Shall we remount journaled fs. with appropriate commit interval? (1=yes)

DO_REMOUNTS=${DO_REMOUNTS:-'1'}

# And shall we add the "noatime" option to that as well? (1=yes)

DO_REMOUNT_NOATIME=${DO_REMOUNT_NOATIME:-'1'}

# Shall we adjust the idle timeout on a hard drive?

DO_HD=${DO_HD:-'1'}

# Adjust idle timeout on which hard drive?

HD="${HD:-'/dev/hda'}"

# spindown time for HD (hdparm -S values)

AC_HD=${AC_HD:-'244'}

BATT_HD=${BATT_HD:-'4'}

# Dirty synchronous ratio.  At this percentage of dirty pages the process which

# calls write() does its own writeback

DIRTY_RATIO=${DIRTY_RATIO:-'40'}

# cpu frequency scaling

# See Documentation/cpu-freq/user-guide.txt for more info

DO_CPU=${CPU_MANAGE:-'0'}

CPU_MAXFREQ=${CPU_MAXFREQ:-'slowest'}

#

# Allowed dirty background ratio, in percent.  Once DIRTY_RATIO has been

# exceeded, the kernel will wake pdflush which will then reduce the amount

# of dirty memory to dirty_background_ratio.  Set this nice and low, so once

# some writeout has commenced, we do a lot of it.

#

DIRTY_BACKGROUND_RATIO=${DIRTY_BACKGROUND_RATIO:-'5'}

# kernel default dirty buffer age

DEF_AGE=${DEF_AGE:-'30'}

DEF_UPDATE=${DEF_UPDATE:-'5'}

DEF_DIRTY_BACKGROUND_RATIO=${DEF_DIRTY_BACKGROUND_RATIO:-'10'}

DEF_DIRTY_RATIO=${DEF_DIRTY_RATIO:-'40'}

DEF_XFS_AGE_BUFFER=${DEF_XFS_AGE_BUFFER:-'15'}

DEF_XFS_SYNC_INTERVAL=${DEF_XFS_SYNC_INTERVAL:-'30'}

DEF_XFS_BUFD_INTERVAL=${DEF_XFS_BUFD_INTERVAL:-'1'}

# This must be adjusted manually to the value of HZ in the running kernel

# on 2.4, until the XFS people change their 2.4 external interfaces to work in

# centisecs. This can be automated, but it's a work in progress that still needs

# some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for external

# interfaces, and that is currently always set to 100. So you don't need to

# change this on 2.6.

XFS_HZ=${XFS_HZ:-'100'}

#############################################################################

KLEVEL="$(uname -r |

             {

	       IFS='.' read a b c

	       echo $a.$b

	     }

)"

case "$KLEVEL" in

	"2.4"|"2.6")

		;;

	*)

		echo "Unhandled kernel version: $KLEVEL ('uname -r' = '$(uname -r)')" >&2

		exit 1

		;;

esac

if [ ! -e /proc/sys/vm/laptop_mode ] ; then

	echo "Kernel is not patched with laptop_mode patch." >&2

	exit 1

fi

if [ ! -w /proc/sys/vm/laptop_mode ] ; then

	echo "You do not have enough privileges to enable laptop_mode." >&2

	exit 1

fi

# Remove an option (the first parameter) of the form option=<number> from

# a mount options string (the rest of the parameters).

parse_mount_opts () {

	OPT="$1"

	shift

	echo ",$*," | sed		\

	 -e 's/,'"$OPT"'=[0-9]*,/,/g'	\

	 -e 's/,,*/,/g'			\

	 -e 's/^,//'			\

	 -e 's/,$//'

}

# Remove an option (the first parameter) without any arguments from

# a mount option string (the rest of the parameters).

parse_nonumber_mount_opts () {

	OPT="$1"

	shift

	echo ",$*," | sed		\

	 -e 's/,'"$OPT"',/,/g'		\

	 -e 's/,,*/,/g'			\

	 -e 's/^,//'			\

	 -e 's/,$//'

}

# Find out the state of a yes/no option (e.g. "atime"/"noatime") in

# fstab for a given filesystem, and use this state to replace the

# value of the option in another mount options string. The device

# is the first argument, the option name the second, and the default

# value the third. The remainder is the mount options string.

#

# Example:

# parse_yesno_opts_wfstab /dev/hda1 atime atime defaults,noatime

#

# If fstab contains, say, "rw" for this filesystem, then the result

# will be "defaults,atime".

parse_yesno_opts_wfstab () {

	L_DEV="$1"

	OPT="$2"

	DEF_OPT="$3"

	shift 3

	L_OPTS="$*"

	PARSEDOPTS1="$(parse_nonumber_mount_opts $OPT $L_OPTS)"

	PARSEDOPTS1="$(parse_nonumber_mount_opts no$OPT $PARSEDOPTS1)"

	# Watch for a default atime in fstab

	FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)"

	if echo "$FSTAB_OPTS" | grep "$OPT" > /dev/null ; then

		# option specified in fstab: extract the value and use it

		if echo "$FSTAB_OPTS" | grep "no$OPT" > /dev/null ; then

			echo "$PARSEDOPTS1,no$OPT"

		else

			# no$OPT not found -- so we must have $OPT.

			echo "$PARSEDOPTS1,$OPT"

		fi

	else

		# option not specified in fstab -- choose the default.

		echo "$PARSEDOPTS1,$DEF_OPT"

	fi

}

# Find out the state of a numbered option (e.g. "commit=NNN") in

# fstab for a given filesystem, and use this state to replace the

# value of the option in another mount options string. The device

# is the first argument, and the option name the second. The

# remainder is the mount options string in which the replacement

# must be done.

#

# Example:

# parse_mount_opts_wfstab /dev/hda1 commit defaults,commit=7

#

# If fstab contains, say, "commit=3,rw" for this filesystem, then the

# result will be "rw,commit=3".

parse_mount_opts_wfstab () {

	L_DEV="$1"

	OPT="$2"

	shift 2

	L_OPTS="$*"

	PARSEDOPTS1="$(parse_mount_opts $OPT $L_OPTS)"

	# Watch for a default commit in fstab

	FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)"

	if echo "$FSTAB_OPTS" | grep "$OPT=" > /dev/null ; then

		# option specified in fstab: extract the value, and use it

		echo -n "$PARSEDOPTS1,$OPT="

		echo ",$FSTAB_OPTS," | sed \

		 -e 's/.*,'"$OPT"'=//'	\

		 -e 's/,.*//'

	else

		# option not specified in fstab: set it to 0

		echo "$PARSEDOPTS1,$OPT=0"

	fi

}

deduce_fstype () {

	MP="$1"

	# My root filesystem unfortunately has

	# type "unknown" in /etc/mtab. If we encounter

	# "unknown", we try to get the type from fstab.

	cat /etc/fstab |

	grep -v '^#' |

	while read FSTAB_DEV FSTAB_MP FSTAB_FST FSTAB_OPTS FSTAB_DUMP FSTAB_DUMP ; do

		if [ "$FSTAB_MP" = "$MP" ]; then

			echo $FSTAB_FST

			exit 0

		fi

	done

}

if [ $DO_REMOUNT_NOATIME -eq 1 ] ; then

	NOATIME_OPT=",noatime"

fi

case "$1" in

	start)

		AGE=$((100*$MAX_AGE))

		XFS_AGE=$(($XFS_HZ*$MAX_AGE))

		echo -n "Starting laptop_mode"

		if [ -d /proc/sys/vm/pagebuf ] ; then

			# (For 2.4 and early 2.6.)

			# This only needs to be set, not reset -- it is only used when

			# laptop mode is enabled.

			echo $XFS_AGE > /proc/sys/vm/pagebuf/lm_flush_age

			echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval

		elif [ -f /proc/sys/fs/xfs/lm_age_buffer ] ; then

			# (A couple of early 2.6 laptop mode patches had these.)

			# The same goes for these.

			echo $XFS_AGE > /proc/sys/fs/xfs/lm_age_buffer

			echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval

		elif [ -f /proc/sys/fs/xfs/age_buffer ] ; then

			# (2.6.6)

			# But not for these -- they are also used in normal

			# operation.

			echo $XFS_AGE > /proc/sys/fs/xfs/age_buffer

			echo $XFS_AGE > /proc/sys/fs/xfs/sync_interval

		elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then

			# (2.6.7 upwards)

			# And not for these either. These are in centisecs,

			# not USER_HZ, so we have to use $AGE, not $XFS_AGE.

			echo $AGE > /proc/sys/fs/xfs/age_buffer_centisecs

			echo $AGE > /proc/sys/fs/xfs/xfssyncd_centisecs

			echo 3000 > /proc/sys/fs/xfs/xfsbufd_centisecs

		fi

		case "$KLEVEL" in

			"2.4")

				echo 1					> /proc/sys/vm/laptop_mode

				echo "30 500 0 0 $AGE $AGE 60 20 0"	> /proc/sys/vm/bdflush

				;;

			"2.6")

				echo 5					> /proc/sys/vm/laptop_mode

				echo "$AGE"				> /proc/sys/vm/dirty_writeback_centisecs

				echo "$AGE"				> /proc/sys/vm/dirty_expire_centisecs

				echo "$DIRTY_RATIO"			> /proc/sys/vm/dirty_ratio

				echo "$DIRTY_BACKGROUND_RATIO"		> /proc/sys/vm/dirty_background_ratio

				;;

		esac

		if [ $DO_REMOUNTS -eq 1 ]; then

			cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do

				PARSEDOPTS="$(parse_mount_opts "$OPTS")"

				if [ "$FST" = 'unknown' ]; then

					FST=$(deduce_fstype $MP)

				fi

				case "$FST" in

					"ext3"|"reiserfs")

						PARSEDOPTS="$(parse_mount_opts commit "$OPTS")"

						mount $DEV -t $FST $MP -o remount,$PARSEDOPTS,commit=$MAX_AGE$NOATIME_OPT

						;;

					"xfs")

						mount $DEV -t $FST $MP -o remount,$OPTS$NOATIME_OPT

						;;

				esac

				if [ -b $DEV ] ; then

					blockdev --setra $(($READAHEAD * 2)) $DEV

				fi

			done

		fi

		if [ $DO_HD -eq 1 ] ; then

			for THISHD in $HD ; do

				/sbin/hdparm -S $BATT_HD $THISHD > /dev/null 2>&1

				/sbin/hdparm -B 1 $THISHD > /dev/null 2>&1

			done

		fi

		if [ $DO_CPU -eq 1 ]; then

			for THISCPU in /sys/devices/system/cpu/*/; do

				if [ -e $THISCPU/cpufreq/cpuinfo_min_freq ]; then

					if [ $CPU_MAXFREQ = 'slowest' ]; then

						CPU_MAXFREQ=`cat $THISCPU/cpufreq/cpuinfo_min_freq`

					fi

					echo $CPU_MAXFREQ > $THISCPU/cpufreq/scaling_max_freq

				fi

			done

		fi

		echo "."

		;;

	stop)

		U_AGE=$((100*$DEF_UPDATE))

		B_AGE=$((100*$DEF_AGE))

		echo -n "Stopping laptop_mode"

		echo 0 > /proc/sys/vm/laptop_mode

		if [ -f /proc/sys/fs/xfs/age_buffer -a ! -f /proc/sys/fs/xfs/lm_age_buffer ] ; then

			# These need to be restored, if there are no lm_*.

			echo $(($XFS_HZ*$DEF_XFS_AGE_BUFFER))	 	> /proc/sys/fs/xfs/age_buffer

			echo $(($XFS_HZ*$DEF_XFS_SYNC_INTERVAL)) 	> /proc/sys/fs/xfs/sync_interval

		elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then

			# These need to be restored as well.

			echo $((100*$DEF_XFS_AGE_BUFFER))	> /proc/sys/fs/xfs/age_buffer_centisecs

			echo $((100*$DEF_XFS_SYNC_INTERVAL))	> /proc/sys/fs/xfs/xfssyncd_centisecs

			echo $((100*$DEF_XFS_BUFD_INTERVAL))	> /proc/sys/fs/xfs/xfsbufd_centisecs

		fi

		case "$KLEVEL" in

			"2.4")

				echo "30 500 0 0 $U_AGE $B_AGE 60 20 0"	> /proc/sys/vm/bdflush

				;;

			"2.6")

				echo "$U_AGE"				> /proc/sys/vm/dirty_writeback_centisecs

				echo "$B_AGE"				> /proc/sys/vm/dirty_expire_centisecs

				echo "$DEF_DIRTY_RATIO"			> /proc/sys/vm/dirty_ratio

				echo "$DEF_DIRTY_BACKGROUND_RATIO"	> /proc/sys/vm/dirty_background_ratio

				;;

		esac

		if [ $DO_REMOUNTS -eq 1 ] ; then

			cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do

				# Reset commit and atime options to defaults.

				if [ "$FST" = 'unknown' ]; then

					FST=$(deduce_fstype $MP)

				fi

				case "$FST" in

					"ext3"|"reiserfs")

						PARSEDOPTS="$(parse_mount_opts_wfstab $DEV commit $OPTS)"

						PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $PARSEDOPTS)"

						mount $DEV -t $FST $MP -o remount,$PARSEDOPTS

						;;

					"xfs")

						PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $OPTS)"

						mount $DEV -t $FST $MP -o remount,$PARSEDOPTS

						;;

				esac

				if [ -b $DEV ] ; then

					blockdev --setra 256 $DEV

				fi

			done

		fi

		if [ $DO_HD -eq 1 ] ; then

			for THISHD in $HD ; do

				/sbin/hdparm -S $AC_HD $THISHD > /dev/null 2>&1

				/sbin/hdparm -B 255 $THISHD > /dev/null 2>&1

			done

		fi

		if [ $DO_CPU -eq 1 ]; then

			for THISCPU in /sys/devices/system/cpu/*/; do

				if [ -e $THISCPU/cpufreq/cpuinfo_min_freq ]; then

					echo `cat $THISCPU/cpufreq/cpuinfo_max_freq` > $THISCPU/cpufreq/scaling_max_freq

				fi

			done

		fi

		echo "."

		;;

	*)

		echo "Usage: $0 {start|stop}" 2>&1

		exit 1

		;;

esac

exit 0