[PATCH v3 12/59] irqchip/gic-v3-its: Generalize device table allocation

Marc Zyngier
2017-07-31T17:25:50Z

As we want to use 2-level tables for VCPUs, let's hack the device
table allocator in order to make it slightly more generic. It
will get reused in subsequent patches.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
drivers/irqchip/irq-gic-v3-its.c | 26 ++++++++++++++++----------
1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 1298a9bca56a..1c2d6bdf85cb 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1386,26 +1386,19 @@ static struct its_baser *its_get_baser(struct its_node *its, u32 type)
return NULL;
}

-static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
+static bool its_alloc_table_entry(struct its_baser *baser, u32 id)
{
- struct its_baser *baser;
struct page *page;
u32 esz, idx;
__le64 *table;

- baser = its_get_baser(its, GITS_BASER_TYPE_DEVICE);
-
- /* Don't allow device id that exceeds ITS hardware limit */
- if (!baser)
- return (ilog2(dev_id) < its->device_ids);
-
/* Don't allow device id that exceeds single, flat table limit */
esz = GITS_BASER_ENTRY_SIZE(baser->val);
if (!(baser->val & GITS_BASER_INDIRECT))
- return (dev_id < (PAGE_ORDER_TO_SIZE(baser->order) / esz));
+ return (id < (PAGE_ORDER_TO_SIZE(baser->order) / esz));

/* Compute 1st level table index & check if that exceeds table limit */
- idx = dev_id >> ilog2(baser->psz / esz);
+ idx = id >> ilog2(baser->psz / esz);
if (idx >= (PAGE_ORDER_TO_SIZE(baser->order) / GITS_LVL1_ENTRY_SIZE))
return false;

@@ -1434,6 +1427,19 @@ static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
return true;
}

+static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
+{
+ struct its_baser *baser;
+
+ baser = its_get_baser(its, GITS_BASER_TYPE_DEVICE);
+
+ /* Don't allow device id that exceeds ITS hardware limit */
+ if (!baser)
+ return (ilog2(dev_id) < its->device_ids);
+
+ return its_alloc_table_entry(baser, dev_id);
+}
+
static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
int nvecs)
{
--
2.11.0