[PATCH] irqchip/gic-v3-its: Don't confuse get_vlpi_map() by writing DB config

[Zenghui Yu <yuzenghui@huawei.com>]

When we're writing config for the doorbell interrupt, get_vlpi_map() will
get confused by doorbell's d->parent_data hack and find the wrong its_dev
as chip data and the wrong event.

Fix this issue by making sure no doorbells will be involved before invoking
get_vlpi_map(), which restore some of the logic in lpi_write_config().

Fixes: c1d4d5cd203c ("irqchip/gic-v3-its: Add its_vlpi_map helpers")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
---

This is based on mainline and can't be directly applied to the current
irqchip-next.

 drivers/irqchip/irq-gic-v3-its.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index e05673bcd52b..cc8a4fcbd6d6 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1181,12 +1181,13 @@ static struct its_vlpi_map *get_vlpi_map(struct irq_data *d)
 
 static void lpi_write_config(struct irq_data *d, u8 clr, u8 set)
 {
-	struct its_vlpi_map *map = get_vlpi_map(d);
 	irq_hw_number_t hwirq;
 	void *va;
 	u8 *cfg;
 
-	if (map) {
+	if (irqd_is_forwarded_to_vcpu(d)) {
+		struct its_vlpi_map *map = get_vlpi_map(d);
+
 		va = page_address(map->vm->vprop_page);
 		hwirq = map->vintid;
 
-- 
2.19.1