Commit 11635fa2 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

irqchip/gic-v3-its: Make vlpi_lock a spinlock 



The VLPI map is currently a mutex, and that's a bad idea as
this lock can be taken in non-preemptible contexts. Convert
it to a raw spinlock, and turn the memory allocation of the
VLPI map to be atomic.

Reported-by: default avatarHeyi Guo <guoheyi@huawei.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20191108165805.3071-12-maz@kernel.org
parent 046b5054

drivers/irqchip/irq-gic-v3-its.c

+9 −9
Original line number Diff line number Diff line
@@ -132,7 +132,7 @@ struct event_lpi_map { 
	u16			*col_map;

	irq_hw_number_t		lpi_base;

	int			nr_lpis;

	struct mutex		vlpi_lock;

	raw_spinlock_t		vlpi_lock;

	struct its_vm		*vm;

	struct its_vlpi_map	*vlpi_maps;

	int			nr_vlpis;
@@ -1436,13 +1436,13 @@ static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info) 
	if (!info->map)

		return -EINVAL;



	mutex_lock(&its_dev->event_map.vlpi_lock);

	raw_spin_lock(&its_dev->event_map.vlpi_lock);



	if (!its_dev->event_map.vm) {

		struct its_vlpi_map *maps;



		maps = kcalloc(its_dev->event_map.nr_lpis, sizeof(*maps),

			       GFP_KERNEL);

			       GFP_ATOMIC);

		if (!maps) {

			ret = -ENOMEM;

			goto out;
@@ -1485,7 +1485,7 @@ static int its_vlpi_map(struct irq_data *d, struct its_cmd_info *info) 
	}



out:

	mutex_unlock(&its_dev->event_map.vlpi_lock);

	raw_spin_unlock(&its_dev->event_map.vlpi_lock);

	return ret;

}
@@ -1495,7 +1495,7 @@ static int its_vlpi_get(struct irq_data *d, struct its_cmd_info *info) 
	struct its_vlpi_map *map;

	int ret = 0;



	mutex_lock(&its_dev->event_map.vlpi_lock);

	raw_spin_lock(&its_dev->event_map.vlpi_lock);



	map = get_vlpi_map(d);
@@ -1508,7 +1508,7 @@ static int its_vlpi_get(struct irq_data *d, struct its_cmd_info *info) 
	*info->map = *map;



out:

	mutex_unlock(&its_dev->event_map.vlpi_lock);

	raw_spin_unlock(&its_dev->event_map.vlpi_lock);

	return ret;

}
@@ -1518,7 +1518,7 @@ static int its_vlpi_unmap(struct irq_data *d) 
	u32 event = its_get_event_id(d);

	int ret = 0;



	mutex_lock(&its_dev->event_map.vlpi_lock);

	raw_spin_lock(&its_dev->event_map.vlpi_lock);



	if (!its_dev->event_map.vm || !irqd_is_forwarded_to_vcpu(d)) {

		ret = -EINVAL;
@@ -1548,7 +1548,7 @@ static int its_vlpi_unmap(struct irq_data *d) 
	}



out:

	mutex_unlock(&its_dev->event_map.vlpi_lock);

	raw_spin_unlock(&its_dev->event_map.vlpi_lock);

	return ret;

}
@@ -2608,7 +2608,7 @@ static struct its_device *its_create_device(struct its_node *its, u32 dev_id, 
	dev->event_map.col_map = col_map;

	dev->event_map.lpi_base = lpi_base;

	dev->event_map.nr_lpis = nr_lpis;

	mutex_init(&dev->event_map.vlpi_lock);

	raw_spin_lock_init(&dev->event_map.vlpi_lock);

	dev->device_id = dev_id;

	INIT_LIST_HEAD(&dev->entry);

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