noop-iosched.c 894 Bytes
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/*
 * elevator noop
 */
#include <linux/blkdev.h>
#include <linux/elevator.h>
#include <linux/bio.h>
#include <linux/module.h>
#include <linux/init.h>

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static void elevator_noop_add_request(request_queue_t *q, struct request *rq)
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{
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	rq->flags |= REQ_NOMERGE;
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	elv_dispatch_add_tail(q, rq);
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}

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static int elevator_noop_dispatch(request_queue_t *q, int force)
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{
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	return 0;
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}

static struct elevator_type elevator_noop = {
	.ops = {
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		.elevator_dispatch_fn		= elevator_noop_dispatch,
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		.elevator_add_req_fn		= elevator_noop_add_request,
	},
	.elevator_name = "noop",
	.elevator_owner = THIS_MODULE,
};

static int __init noop_init(void)
{
	return elv_register(&elevator_noop);
}

static void __exit noop_exit(void)
{
	elv_unregister(&elevator_noop);
}

module_init(noop_init);
module_exit(noop_exit);


MODULE_AUTHOR("Jens Axboe");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("No-op IO scheduler");