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: Heyi Guo <guoheyi@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20191108165805.3071-12-maz@kernel.org
This commit is contained in:
Marc Zyngier 2019-11-08 16:58:05 +00:00
parent 046b5054f5
commit 11635fa26d

View File

@ -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);