[PATCH] iommu/amd: Re-factor guest virtual APIC (de-)activation code

[Suthikulpanit, Suravee]

Re-factore the logic for activate/deactivate guest virtual APIC mode (GAM)
into helper functions, and export them for other drivers (e.g. SVM).
to support run-time activate/deactivate of SVM AVIC.

Cc: Joerg Roedel <joro@xxxxxxxxxx>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
---
 drivers/iommu/amd_iommu.c       | 85 +++++++++++++++++++++++++++++------------
 drivers/iommu/amd_iommu_types.h |  9 +++++
 include/linux/amd-iommu.h       | 12 ++++++
 3 files changed, 82 insertions(+), 24 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index dce1d8d..42fba8d 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -4301,13 +4301,62 @@ static void irq_remapping_deactivate(struct irq_domain *domain,
 	.deactivate = irq_remapping_deactivate,
 };
 
+int amd_iommu_activate_guest_mode(void *data)
+{
+	struct amd_ir_data *ir_data = (struct amd_ir_data *)data;
+	struct irte_ga *entry = (struct irte_ga *) ir_data->entry;
+
+	if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) ||
+	    !entry || entry->lo.fields_vapic.guest_mode)
+		return 0;
+
+	entry->lo.val = 0;
+	entry->hi.val = 0;
+
+	entry->lo.fields_vapic.guest_mode  = 1;
+	entry->lo.fields_vapic.ga_log_intr = 1;
+	entry->hi.fields.ga_root_ptr       = ir_data->ga_root_ptr;
+	entry->hi.fields.vector            = ir_data->ga_vector;
+	entry->lo.fields_vapic.ga_tag      = ir_data->ga_tag;
+
+	return modify_irte_ga(ir_data->irq_2_irte.devid,
+			      ir_data->irq_2_irte.index, entry, NULL);
+}
+EXPORT_SYMBOL(amd_iommu_activate_guest_mode);
+
+int amd_iommu_deactivate_guest_mode(void *data)
+{
+	struct amd_ir_data *ir_data = (struct amd_ir_data *)data;
+	struct irte_ga *entry = (struct irte_ga *) ir_data->entry;
+	struct irq_cfg *cfg = ir_data->cfg;
+
+	if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) ||
+	    !entry || !entry->lo.fields_vapic.guest_mode)
+		return 0;
+
+	entry->lo.val = 0;
+	entry->hi.val = 0;
+
+	entry->lo.fields_remap.dm          = apic->irq_dest_mode;
+	entry->lo.fields_remap.int_type    = apic->irq_delivery_mode;
+	entry->hi.fields.vector            = cfg->vector;
+	entry->lo.fields_remap.destination =
+				APICID_TO_IRTE_DEST_LO(cfg->dest_apicid);
+	entry->hi.fields.destination =
+				APICID_TO_IRTE_DEST_HI(cfg->dest_apicid);
+
+	return modify_irte_ga(ir_data->irq_2_irte.devid,
+			      ir_data->irq_2_irte.index, entry, NULL);
+}
+EXPORT_SYMBOL(amd_iommu_deactivate_guest_mode);
+
 static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
 {
+	int ret;
 	struct amd_iommu *iommu;
 	struct amd_iommu_pi_data *pi_data = vcpu_info;
 	struct vcpu_data *vcpu_pi_info = pi_data->vcpu_data;
 	struct amd_ir_data *ir_data = data->chip_data;
-	struct irte_ga *irte = (struct irte_ga *) ir_data->entry;
 	struct irq_2_irte *irte_info = &ir_data->irq_2_irte;
 	struct iommu_dev_data *dev_data = search_dev_data(irte_info->devid);
 
@@ -4318,6 +4367,7 @@ static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
 	if (!dev_data || !dev_data->use_vapic)
 		return 0;
 
+	ir_data->cfg = irqd_cfg(data);
 	pi_data->ir_data = ir_data;
 
 	/* Note:
@@ -4336,37 +4386,24 @@ static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
 
 	pi_data->prev_ga_tag = ir_data->cached_ga_tag;
 	if (pi_data->is_guest_mode) {
-		/* Setting */
-		irte->hi.fields.ga_root_ptr = (pi_data->base >> 12);
-		irte->hi.fields.vector = vcpu_pi_info->vector;
-		irte->lo.fields_vapic.ga_log_intr = 1;
-		irte->lo.fields_vapic.guest_mode = 1;
-		irte->lo.fields_vapic.ga_tag = pi_data->ga_tag;
-
-		ir_data->cached_ga_tag = pi_data->ga_tag;
+		ir_data->ga_root_ptr = (pi_data->base >> 12);
+		ir_data->ga_vector = vcpu_pi_info->vector;
+		ir_data->ga_tag = pi_data->ga_tag;
+		ret = amd_iommu_activate_guest_mode(ir_data);
+		if (!ret)
+			ir_data->cached_ga_tag = pi_data->ga_tag;
 	} else {
-		/* Un-Setting */
-		struct irq_cfg *cfg = irqd_cfg(data);
-
-		irte->hi.val = 0;
-		irte->lo.val = 0;
-		irte->hi.fields.vector = cfg->vector;
-		irte->lo.fields_remap.guest_mode = 0;
-		irte->lo.fields_remap.destination =
-				APICID_TO_IRTE_DEST_LO(cfg->dest_apicid);
-		irte->hi.fields.destination =
-				APICID_TO_IRTE_DEST_HI(cfg->dest_apicid);
-		irte->lo.fields_remap.int_type = apic->irq_delivery_mode;
-		irte->lo.fields_remap.dm = apic->irq_dest_mode;
+		ret = amd_iommu_deactivate_guest_mode(ir_data);
 
 		/*
 		 * This communicates the ga_tag back to the caller
 		 * so that it can do all the necessary clean up.
 		 */
-		ir_data->cached_ga_tag = 0;
+		if (!ret)
+			ir_data->cached_ga_tag = 0;
 	}
 
-	return modify_irte_ga(irte_info->devid, irte_info->index, irte, ir_data);
+	return ret;
 }
 
 
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index 64edd5a..9ac229e 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -873,6 +873,15 @@ struct amd_ir_data {
 	struct msi_msg msi_entry;
 	void *entry;    /* Pointer to union irte or struct irte_ga */
 	void *ref;      /* Pointer to the actual irte */
+
+	/**
+	 * Store information for activate/de-activate
+	 * Guest virtual APIC mode during runtime.
+	 */
+	struct irq_cfg *cfg;
+	int ga_vector;
+	int ga_root_ptr;
+	int ga_tag;
 };
 
 struct amd_irte_ops {
diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h
index 4a4d006..21e950e 100644
--- a/include/linux/amd-iommu.h
+++ b/include/linux/amd-iommu.h
@@ -184,6 +184,9 @@ extern int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev,
 extern int
 amd_iommu_update_ga(int cpu, bool is_run, void *data);
 
+extern int amd_iommu_activate_guest_mode(void *data);
+extern int amd_iommu_deactivate_guest_mode(void *data);
+
 #else /* defined(CONFIG_AMD_IOMMU) && defined(CONFIG_IRQ_REMAP) */
 
 static inline int
@@ -198,6 +201,15 @@ extern int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev,
 	return 0;
 }
 
+static inline int amd_iommu_activate_guest_mode(void *data)
+{
+	return 0;
+}
+
+static inline int amd_iommu_deactivate_guest_mode(void *data)
+{
+	return 0;
+}
 #endif /* defined(CONFIG_AMD_IOMMU) && defined(CONFIG_IRQ_REMAP) */
 
 #endif /* _ASM_X86_AMD_IOMMU_H */
-- 
1.8.3.1