Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e17a9489 authored by Al Viro's avatar Al Viro
Browse files

[PATCH] stop elv_unregister() from rogering other iosched's data, fix locking 



Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 25975f86

block/as-iosched.c

+7 −0
Original line number Diff line number Diff line
@@ -195,6 +195,12 @@ static void free_as_io_context(struct as_io_context *aic) 
	kfree(aic);

}



static void as_trim(struct io_context *ioc)

{

	kfree(ioc->aic);

	ioc->aic = NULL;

}



/* Called when the task exits */

static void exit_as_io_context(struct as_io_context *aic)

{
@@ -1860,6 +1866,7 @@ static struct elevator_type iosched_as = { 
		.elevator_may_queue_fn =	as_may_queue,

		.elevator_init_fn =		as_init_queue,

		.elevator_exit_fn =		as_exit_queue,

		.trim =				as_trim,

	},



	.elevator_ktype = &as_ktype,

block/cfq-iosched.c

+8 −0
Original line number Diff line number Diff line
@@ -1211,6 +1211,13 @@ static void cfq_free_io_context(struct cfq_io_context *cic) 
	kmem_cache_free(cfq_ioc_pool, cic);

}



static void cfq_trim(struct io_context *ioc)

{

	ioc->set_ioprio = NULL;

	if (ioc->cic)

		cfq_free_io_context(ioc->cic);

}



/*

 * Called with interrupts disabled

 */
@@ -2472,6 +2479,7 @@ static struct elevator_type iosched_cfq = { 
		.elevator_may_queue_fn =	cfq_may_queue,

		.elevator_init_fn =		cfq_init_queue,

		.elevator_exit_fn =		cfq_exit_queue,

		.trim =				cfq_trim,

	},

	.elevator_ktype =	&cfq_ktype,

	.elevator_name =	"cfq",

block/elevator.c

+9 −15
Original line number Diff line number Diff line
@@ -675,21 +675,15 @@ void elv_unregister(struct elevator_type *e) 
	/*

	 * Iterate every thread in the process to remove the io contexts.

	 */

	if (e->ops.trim) {

		read_lock(&tasklist_lock);

		do_each_thread(g, p) {

		struct io_context *ioc = p->io_context;

		if (ioc && ioc->cic) {

			ioc->cic->exit(ioc->cic);

			ioc->cic->dtor(ioc->cic);

			ioc->cic = NULL;

		}

		if (ioc && ioc->aic) {

			ioc->aic->exit(ioc->aic);

			ioc->aic->dtor(ioc->aic);

			ioc->aic = NULL;

		}

			task_lock(p);

			e->ops.trim(p->io_context);

			task_unlock(p);

		} while_each_thread(g, p);

		read_unlock(&tasklist_lock);

	}



	spin_lock_irq(&elv_list_lock);

	list_del_init(&e->list);

include/linux/elevator.h

+1 −0
Original line number Diff line number Diff line
@@ -48,6 +48,7 @@ struct elevator_ops 


	elevator_init_fn *elevator_init_fn;

	elevator_exit_fn *elevator_exit_fn;

	void (*trim)(struct io_context *);

};



#define ELV_NAME_MAX	(16)