iommu/amd: Implements irq_set_vcpu_affinity() hook to setup vapic mode for pass-throu...

This patch implements irq_set_vcpu_affinity() function to set up interrupt
remapping table entry with vapic mode for pass-through devices.

In case requirements for vapic mode are not met, it falls back to set up
the IRTE in legacy mode.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 089e1ed4deec1bdc8bd90d1177336c1a520c90a0..69fc57e0b975d06628714f2c5747825a76f7367d 100644 (file)
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3718,7 +3718,8 @@ out:
        return index;
 }
 
-static int modify_irte_ga(u16 devid, int index, struct irte_ga *irte)
+static int modify_irte_ga(u16 devid, int index, struct irte_ga *irte,
+                         struct amd_ir_data *data)
 {
        struct irq_remap_table *table;
        struct amd_iommu *iommu;
@@ -3741,6 +3742,8 @@ static int modify_irte_ga(u16 devid, int index, struct irte_ga *irte)
        entry->hi.val = irte->hi.val;
        entry->lo.val = irte->lo.val;
        entry->lo.fields_remap.valid = 1;
+       if (data)
+               data->ref = entry;
 
        spin_unlock_irqrestore(&table->lock, flags);
 
@@ -3839,7 +3842,7 @@ static void irte_ga_activate(void *entry, u16 devid, u16 index)
        struct irte_ga *irte = (struct irte_ga *) entry;
 
        irte->lo.fields_remap.valid = 1;
-       modify_irte_ga(devid, index, irte);
+       modify_irte_ga(devid, index, irte, NULL);
 }
 
 static void irte_deactivate(void *entry, u16 devid, u16 index)
@@ -3855,7 +3858,7 @@ static void irte_ga_deactivate(void *entry, u16 devid, u16 index)
        struct irte_ga *irte = (struct irte_ga *) entry;
 
        irte->lo.fields_remap.valid = 0;
-       modify_irte_ga(devid, index, irte);
+       modify_irte_ga(devid, index, irte, NULL);
 }
 
 static void irte_set_affinity(void *entry, u16 devid, u16 index,
@@ -3876,7 +3879,7 @@ static void irte_ga_set_affinity(void *entry, u16 devid, u16 index,
        irte->hi.fields.vector = vector;
        irte->lo.fields_remap.destination = dest_apicid;
        irte->lo.fields_remap.guest_mode = 0;
-       modify_irte_ga(devid, index, irte);
+       modify_irte_ga(devid, index, irte, NULL);
 }
 
 #define IRTE_ALLOCATED (~1U)
@@ -4211,6 +4214,62 @@ static struct irq_domain_ops amd_ir_domain_ops = {
        .deactivate = irq_remapping_deactivate,
 };
 
+static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
+{
+       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;
+
+       pi_data->ir_data = ir_data;
+
+       /* Note:
+        * SVM tries to set up for VAPIC mode, but we are in
+        * legacy mode. So, we force legacy mode instead.
+        */
+       if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir)) {
+               pr_debug("AMD-Vi: %s: Fall back to using intr legacy remap\n",
+                        __func__);
+               pi_data->is_guest_mode = false;
+       }
+
+       iommu = amd_iommu_rlookup_table[irte_info->devid];
+       if (iommu == NULL)
+               return -EINVAL;
+
+       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.guest_mode = 1;
+               irte->lo.fields_vapic.ga_tag = pi_data->ga_tag;
+
+               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 = cfg->dest_apicid;
+               irte->lo.fields_remap.int_type = apic->irq_delivery_mode;
+               irte->lo.fields_remap.dm = apic->irq_dest_mode;
+
+               /*
+                * 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;
+       }
+
+       return modify_irte_ga(irte_info->devid, irte_info->index, irte, ir_data);
+}
+
 static int amd_ir_set_affinity(struct irq_data *data,
                               const struct cpumask *mask, bool force)
 {
@@ -4255,6 +4314,7 @@ static void ir_compose_msi_msg(struct irq_data *irq_data, struct msi_msg *msg)
 static struct irq_chip amd_ir_chip = {
        .irq_ack = ir_ack_apic_edge,
        .irq_set_affinity = amd_ir_set_affinity,
+       .irq_set_vcpu_affinity = amd_ir_set_vcpu_affinity,
        .irq_compose_msi_msg = ir_compose_msi_msg,
 };
 

diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index 60018a8fb655262da5813797478f279f7f43da6b..79e91e68ee76066c22dfb6fe744348304e7b898d 100644 (file)
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -807,6 +807,7 @@ struct irq_2_irte {
 };
 
 struct amd_ir_data {
+       u32 cached_ga_tag;
        struct irq_2_irte irq_2_irte;
        struct msi_msg msi_entry;
        void *entry;    /* Pointer to union irte or struct irte_ga */

diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h
index d8d48aca0eb77836b7a7c7f57d4e76e502362142..09751d349963aedc274a7e245da12273bb0dbd4e 100644 (file)
--- a/include/linux/amd-iommu.h
+++ b/include/linux/amd-iommu.h
@@ -22,6 +22,20 @@
 
 #include <linux/types.h>
 
+/*
+ * This is mainly used to communicate information back-and-forth
+ * between SVM and IOMMU for setting up and tearing down posted
+ * interrupt
+ */
+struct amd_iommu_pi_data {
+       u32 ga_tag;
+       u32 prev_ga_tag;
+       u64 base;
+       bool is_guest_mode;
+       struct vcpu_data *vcpu_data;
+       void *ir_data;
+};
+
 #ifdef CONFIG_AMD_IOMMU
 
 struct task_struct;