[PATCH v2 39/52] KVM: arm/arm64: GICv4: Wire mapping/unmapping of VLPIs in VFIO irq bypass

[Marc Zyngier]

Let's use the irq bypass mechanism introduced for platform device
interrupts to intercept the virtual PCIe endpoint configuration
and establish our LPI->VLPI mapping.

Signed-off-by: Marc Zyngier 
---
 include/kvm/arm_vgic.h  |  8 
 virt/kvm/arm/arm.c  | 27 +
 virt/kvm/arm/vgic/vgic-v4.c | 96 +
 3 files changed, 123 insertions(+), 8 deletions(-)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 359eeffe9857..050f78d4fb42 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -367,4 +367,12 @@ int kvm_vgic_set_forwarding(struct kvm *kvm, unsigned int 
host_irq,
 void kvm_vgic_unset_forwarding(struct kvm *kvm, unsigned int host_irq,
   unsigned int vintid);
 
+struct kvm_kernel_irq_routing_entry;
+
+int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int irq,
+  struct kvm_kernel_irq_routing_entry *irq_entry);
+
+int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
+struct kvm_kernel_irq_routing_entry 
*irq_entry);
+
 #endif /* __KVM_ARM_VGIC_H */
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index ebab6c29e3be..6803ea27c47d 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -1457,11 +1457,16 @@ int kvm_arch_irq_bypass_add_producer(struct 
irq_bypass_consumer *cons,
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
 
-   if (prod->type != IRQ_BYPASS_VFIO_PLATFORM)
+   switch (prod->type) {
+   case IRQ_BYPASS_VFIO_PLATFORM:
+   return kvm_vgic_set_forwarding(irqfd->kvm, prod->irq,
+  irqfd->gsi + 
VGIC_NR_PRIVATE_IRQS);
+   case IRQ_BYPASS_VFIO_PCI_MSI:
+   return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
+ >irq_entry);
+   default:
return 0;
-
-   return kvm_vgic_set_forwarding(irqfd->kvm, prod->irq,
-  irqfd->gsi + VGIC_NR_PRIVATE_IRQS);
+   }
 }
 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
  struct irq_bypass_producer *prod)
@@ -1469,11 +1474,17 @@ void kvm_arch_irq_bypass_del_producer(struct 
irq_bypass_consumer *cons,
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
 
-   if (prod->type != IRQ_BYPASS_VFIO_PLATFORM)
-   return;
+   switch (prod->type) {
+   case IRQ_BYPASS_VFIO_PLATFORM:
+   kvm_vgic_unset_forwarding(irqfd->kvm, prod->irq,
+ irqfd->gsi + VGIC_NR_PRIVATE_IRQS);
+   break;
 
-   kvm_vgic_unset_forwarding(irqfd->kvm, prod->irq,
- irqfd->gsi + VGIC_NR_PRIVATE_IRQS);
+   case IRQ_BYPASS_VFIO_PCI_MSI:
+   kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
+>irq_entry);
+   break;
+   }
 }
 
 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 81f607f2f83b..22cc3871bf03 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -57,3 +57,99 @@ void vgic_v4_teardown(struct kvm *kvm)
its_free_vcpu_irqs(its_vm);
kfree(its_vm->vpes);
 }
+
+static struct vgic_its *vgic_get_its(struct kvm *kvm,
+struct kvm_kernel_irq_routing_entry 
*irq_entry)
+{
+   struct kvm_msi msi  = (struct kvm_msi) {
+   .address_lo = irq_entry->msi.address_lo,
+   .address_hi = irq_entry->msi.address_hi,
+   .data   = irq_entry->msi.data,
+   .flags  = irq_entry->msi.flags,
+   .devid  = irq_entry->msi.devid,
+   };
+
+   /*
+* Get a reference on the LPI. If NULL, this is not a valid
+* translation for any of our vITSs.
+*/
+   return vgic_msi_to_its(kvm, );
+}
+
+int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int virq,
+  struct kvm_kernel_irq_routing_entry *irq_entry)
+{
+   struct vgic_its *its;
+   struct vgic_irq *irq;
+   struct its_vlpi_map map;
+   int ret;
+
+   /*
+* Get the LPI. If NULL, this is not a valid translation for
+* any of our vITSs.
+*/
+   its = vgic_get_its(kvm, irq_entry);
+   if (!its)
+   return 0;
+
+   mutex_lock(>its_lock);
+
+   ret = vgic_its_resolve_lpi(kvm, its, irq_entry->msi.devid,
+  irq_entry->msi.data, );
+   if (ret)
+   goto out;
+
+   /*
+* Emit the mapping request. If it fails, the ITS probably
+* isn't v4 compatible, so 

[PATCH v2 39/52] KVM: arm/arm64: GICv4: Wire mapping/unmapping of VLPIs in VFIO irq bypass

[Marc Zyngier]

Let's use the irq bypass mechanism introduced for platform device
interrupts to intercept the virtual PCIe endpoint configuration
and establish our LPI->VLPI mapping.

Signed-off-by: Marc Zyngier 
---
 include/kvm/arm_vgic.h  |  8 
 virt/kvm/arm/arm.c  | 27 +
 virt/kvm/arm/vgic/vgic-v4.c | 96 +
 3 files changed, 123 insertions(+), 8 deletions(-)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 359eeffe9857..050f78d4fb42 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -367,4 +367,12 @@ int kvm_vgic_set_forwarding(struct kvm *kvm, unsigned int 
host_irq,
 void kvm_vgic_unset_forwarding(struct kvm *kvm, unsigned int host_irq,
   unsigned int vintid);
 
+struct kvm_kernel_irq_routing_entry;
+
+int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int irq,
+  struct kvm_kernel_irq_routing_entry *irq_entry);
+
+int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
+struct kvm_kernel_irq_routing_entry 
*irq_entry);
+
 #endif /* __KVM_ARM_VGIC_H */
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index ebab6c29e3be..6803ea27c47d 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -1457,11 +1457,16 @@ int kvm_arch_irq_bypass_add_producer(struct 
irq_bypass_consumer *cons,
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
 
-   if (prod->type != IRQ_BYPASS_VFIO_PLATFORM)
+   switch (prod->type) {
+   case IRQ_BYPASS_VFIO_PLATFORM:
+   return kvm_vgic_set_forwarding(irqfd->kvm, prod->irq,
+  irqfd->gsi + 
VGIC_NR_PRIVATE_IRQS);
+   case IRQ_BYPASS_VFIO_PCI_MSI:
+   return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
+ >irq_entry);
+   default:
return 0;
-
-   return kvm_vgic_set_forwarding(irqfd->kvm, prod->irq,
-  irqfd->gsi + VGIC_NR_PRIVATE_IRQS);
+   }
 }
 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
  struct irq_bypass_producer *prod)
@@ -1469,11 +1474,17 @@ void kvm_arch_irq_bypass_del_producer(struct 
irq_bypass_consumer *cons,
struct kvm_kernel_irqfd *irqfd =
container_of(cons, struct kvm_kernel_irqfd, consumer);
 
-   if (prod->type != IRQ_BYPASS_VFIO_PLATFORM)
-   return;
+   switch (prod->type) {
+   case IRQ_BYPASS_VFIO_PLATFORM:
+   kvm_vgic_unset_forwarding(irqfd->kvm, prod->irq,
+ irqfd->gsi + VGIC_NR_PRIVATE_IRQS);
+   break;
 
-   kvm_vgic_unset_forwarding(irqfd->kvm, prod->irq,
- irqfd->gsi + VGIC_NR_PRIVATE_IRQS);
+   case IRQ_BYPASS_VFIO_PCI_MSI:
+   kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
+>irq_entry);
+   break;
+   }
 }
 
 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 81f607f2f83b..22cc3871bf03 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -57,3 +57,99 @@ void vgic_v4_teardown(struct kvm *kvm)
its_free_vcpu_irqs(its_vm);
kfree(its_vm->vpes);
 }
+
+static struct vgic_its *vgic_get_its(struct kvm *kvm,
+struct kvm_kernel_irq_routing_entry 
*irq_entry)
+{
+   struct kvm_msi msi  = (struct kvm_msi) {
+   .address_lo = irq_entry->msi.address_lo,
+   .address_hi = irq_entry->msi.address_hi,
+   .data   = irq_entry->msi.data,
+   .flags  = irq_entry->msi.flags,
+   .devid  = irq_entry->msi.devid,
+   };
+
+   /*
+* Get a reference on the LPI. If NULL, this is not a valid
+* translation for any of our vITSs.
+*/
+   return vgic_msi_to_its(kvm, );
+}
+
+int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int virq,
+  struct kvm_kernel_irq_routing_entry *irq_entry)
+{
+   struct vgic_its *its;
+   struct vgic_irq *irq;
+   struct its_vlpi_map map;
+   int ret;
+
+   /*
+* Get the LPI. If NULL, this is not a valid translation for
+* any of our vITSs.
+*/
+   its = vgic_get_its(kvm, irq_entry);
+   if (!its)
+   return 0;
+
+   mutex_lock(>its_lock);
+
+   ret = vgic_its_resolve_lpi(kvm, its, irq_entry->msi.devid,
+  irq_entry->msi.data, );
+   if (ret)
+   goto out;
+
+   /*
+* Emit the mapping request. If it fails, the ITS probably
+* isn't v4 compatible, so let's silently bail