[patch 45/52] iommu/vt-d: Reevaluate vector configuration on activate()

From: Thomas Gleixner
Date: Wed Sep 13 2017 - 17:37:46 EST


With the upcoming reservation/management scheme, early activation will
assign a special vector. The final activation at request_irq() assigns a
real vector, which needs to be updated in the tables.

Split out the reconfiguration code in set_affinity and use it for
reactivation.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
---
drivers/iommu/intel_irq_remapping.c | 38 +++++++++++++++++++-----------------
1 file changed, 21 insertions(+), 17 deletions(-)

--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -1121,6 +1121,24 @@ struct irq_remap_ops intel_irq_remap_ops
.get_irq_domain = intel_get_irq_domain,
};

+static void intel_ir_reconfigure_irte(struct irq_data *irqd, bool force)
+{
+ struct intel_ir_data *ir_data = irqd->chip_data;
+ struct irte *irte = &ir_data->irte_entry;
+ struct irq_cfg *cfg = irqd_cfg(irqd);
+
+ /*
+ * Atomically updates the IRTE with the new destination, vector
+ * and flushes the interrupt entry cache.
+ */
+ irte->vector = cfg->vector;
+ irte->dest_id = IRTE_DEST(cfg->dest_apicid);
+
+ /* Update the hardware only if the interrupt is in remapped mode. */
+ if (!force || ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
+ modify_irte(&ir_data->irq_2_iommu, irte);
+}
+
/*
* Migrate the IO-APIC irq in the presence of intr-remapping.
*
@@ -1139,27 +1157,15 @@ static int
intel_ir_set_affinity(struct irq_data *data, const struct cpumask *mask,
bool force)
{
- struct intel_ir_data *ir_data = data->chip_data;
- struct irte *irte = &ir_data->irte_entry;
- struct irq_cfg *cfg = irqd_cfg(data);
struct irq_data *parent = data->parent_data;
+ struct irq_cfg *cfg = irqd_cfg(data);
int ret;

ret = parent->chip->irq_set_affinity(parent, mask, force);
if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
return ret;

- /*
- * Atomically updates the IRTE with the new destination, vector
- * and flushes the interrupt entry cache.
- */
- irte->vector = cfg->vector;
- irte->dest_id = IRTE_DEST(cfg->dest_apicid);
-
- /* Update the hardware only if the interrupt is in remapped mode. */
- if (ir_data->irq_2_iommu.mode == IRQ_REMAPPING)
- modify_irte(&ir_data->irq_2_iommu, irte);
-
+ intel_ir_reconfigure_irte(data, false);
/*
* After this point, all the interrupts will start arriving
* at the new destination. So, time to cleanup the previous
@@ -1392,9 +1398,7 @@ static void intel_irq_remapping_free(str
static int intel_irq_remapping_activate(struct irq_domain *domain,
struct irq_data *irq_data, bool early)
{
- struct intel_ir_data *data = irq_data->chip_data;
-
- modify_irte(&data->irq_2_iommu, &data->irte_entry);
+ intel_ir_reconfigure_irte(irq_data, true);
return 0;
}