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

Commit a38eb630 authored by Vivek Goyal's avatar Vivek Goyal Committed by Jens Axboe
Browse files

blk-throttle: Take blkcg->lock while traversing blkcg->policy_list 



blkcg->policy_list is protected by blkcg->lock. Its not rcu protected
list. So even for readers, they need to take blkcg->lock. There are
few functions which were reading the list without taking lock. Fix it.

Signed-off-by: default avatarVivek Goyal <vgoyal@redhat.com>
Acked-by: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent e060f00b

block/blk-cgroup.c

+40 −14
Original line number Diff line number Diff line
@@ -869,60 +869,86 @@ unsigned int blkcg_get_weight(struct blkio_cgroup *blkcg, 
			      dev_t dev)

{

	struct blkio_policy_node *pn;

	unsigned long flags;

	unsigned int weight;



	spin_lock_irqsave(&blkcg->lock, flags);



	pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_PROP,

				BLKIO_PROP_weight_device);

	if (pn)

		return pn->val.weight;

		weight = pn->val.weight;

	else

		return blkcg->weight;

		weight = blkcg->weight;



	spin_unlock_irqrestore(&blkcg->lock, flags);



	return weight;

}

EXPORT_SYMBOL_GPL(blkcg_get_weight);



uint64_t blkcg_get_read_bps(struct blkio_cgroup *blkcg, dev_t dev)

{

	struct blkio_policy_node *pn;

	unsigned long flags;

	uint64_t bps = -1;



	spin_lock_irqsave(&blkcg->lock, flags);

	pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,

				BLKIO_THROTL_read_bps_device);

	if (pn)

		return pn->val.bps;

	else

		return -1;

		bps = pn->val.bps;

	spin_unlock_irqrestore(&blkcg->lock, flags);



	return bps;

}



uint64_t blkcg_get_write_bps(struct blkio_cgroup *blkcg, dev_t dev)

{

	struct blkio_policy_node *pn;

	unsigned long flags;

	uint64_t bps = -1;



	spin_lock_irqsave(&blkcg->lock, flags);

	pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,

				BLKIO_THROTL_write_bps_device);

	if (pn)

		return pn->val.bps;

	else

		return -1;

		bps = pn->val.bps;

	spin_unlock_irqrestore(&blkcg->lock, flags);



	return bps;

}



unsigned int blkcg_get_read_iops(struct blkio_cgroup *blkcg, dev_t dev)

{

	struct blkio_policy_node *pn;

	unsigned long flags;

	unsigned int iops = -1;



	spin_lock_irqsave(&blkcg->lock, flags);

	pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,

				BLKIO_THROTL_read_iops_device);

	if (pn)

		return pn->val.iops;

	else

		return -1;

		iops = pn->val.iops;

	spin_unlock_irqrestore(&blkcg->lock, flags);



	return iops;

}



unsigned int blkcg_get_write_iops(struct blkio_cgroup *blkcg, dev_t dev)

{

	struct blkio_policy_node *pn;

	unsigned long flags;

	unsigned int iops = -1;



	spin_lock_irqsave(&blkcg->lock, flags);

	pn = blkio_policy_search_node(blkcg, dev, BLKIO_POLICY_THROTL,

				BLKIO_THROTL_write_iops_device);

	if (pn)

		return pn->val.iops;

	else

		return -1;

		iops = pn->val.iops;

	spin_unlock_irqrestore(&blkcg->lock, flags);



	return iops;

}



/* Checks whether user asked for deleting a policy rule */