Commit 8c279598 authored Oct 09, 2009 by KOSAKI Motohiro Committed by Jens Axboe Oct 09, 2009

elv_iosched_store(): fix strstrip() misuse



elv_iosched_store() ignore the return value of strstrip().  It makes small
inconsistent behavior.

This patch fixes it.

 <before>
 ====================================
 # cd /sys/block/{blockdev}/queue

 case1:
 # echo "anticipatory" > scheduler
 # cat scheduler
 noop [anticipatory] deadline cfq

 case2:
 # echo "anticipatory " > scheduler
 # cat scheduler
 noop [anticipatory] deadline cfq

 case3:
 # echo " anticipatory" > scheduler
 bash: echo: write error: Invalid argument

 <after>
 ====================================
 # cd /sys/block/{blockdev}/queue

 case1:
 # echo "anticipatory" > scheduler
 # cat scheduler
 noop [anticipatory] deadline cfq

 case2:
 # echo "anticipatory " > scheduler
 # cat scheduler
 noop [anticipatory] deadline cfq

 case3:
 # echo " anticipatory" > scheduler
 noop [anticipatory] deadline cfq

Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

parent 355b659c

block/elevator.c

+1 −3

Original line number	Diff line number	Diff line
		@@ -1059,9 +1059,7 @@ ssize_t elv_iosched_store(struct request_queue q, const char name,
		return count;

		strlcpy(elevator_name, name, sizeof(elevator_name));
		strstrip(elevator_name);

		e = elevator_get(elevator_name);
		e = elevator_get(strstrip(elevator_name));
		if (!e) {
		printk(KERN_ERR "elevator: type %s not found\n", elevator_name);
		return -EINVAL;

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