KVM: arm/arm64: GICv4: Wire mapping/unmapping of VLPIs in VFIO irq bypass

Let's use the irq bypass mechanism also used for x86 posted interrupts
to intercept the virtual PCIe endpoint configuration and establish our
LPI->VLPI mapping.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
This commit is contained in:
Marc Zyngier 2017-10-27 15:28:39 +01:00 committed by Christoffer Dall
parent 74fe55dc9a
commit 196b136498
3 changed files with 116 additions and 2 deletions

View File

@ -373,4 +373,12 @@ int kvm_vgic_setup_default_irq_routing(struct kvm *kvm);
int kvm_vgic_set_owner(struct kvm_vcpu *vcpu, unsigned int intid, void *owner);
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 */

View File

@ -1471,7 +1471,8 @@ 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);
return 0;
return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
&irqfd->irq_entry);
}
void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
struct irq_bypass_producer *prod)
@ -1479,7 +1480,8 @@ 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);
return;
kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
&irqfd->irq_entry);
}
void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)

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@ -18,6 +18,7 @@
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/kvm_host.h>
#include <linux/irqchip/arm-gic-v3.h>
#include "vgic.h"
@ -81,3 +82,106 @@ void vgic_v4_teardown(struct kvm *kvm)
its_vm->nr_vpes = 0;
its_vm->vpes = NULL;
}
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,
};
return vgic_msi_to_its(kvm, &msi);
}
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;
if (!vgic_supports_direct_msis(kvm))
return 0;
/*
* Get the ITS, and escape early on error (not a valid
* doorbell for any of our vITSs).
*/
its = vgic_get_its(kvm, irq_entry);
if (IS_ERR(its))
return 0;
mutex_lock(&its->its_lock);
/* Perform then actual DevID/EventID -> LPI translation. */
ret = vgic_its_resolve_lpi(kvm, its, irq_entry->msi.devid,
irq_entry->msi.data, &irq);
if (ret)
goto out;
/*
* Emit the mapping request. If it fails, the ITS probably
* isn't v4 compatible, so let's silently bail out. Holding
* the ITS lock should ensure that nothing can modify the
* target vcpu.
*/
map = (struct its_vlpi_map) {
.vm = &kvm->arch.vgic.its_vm,
.vpe = &irq->target_vcpu->arch.vgic_cpu.vgic_v3.its_vpe,
.vintid = irq->intid,
.properties = ((irq->priority & 0xfc) |
(irq->enabled ? LPI_PROP_ENABLED : 0) |
LPI_PROP_GROUP1),
.db_enabled = true,
};
ret = its_map_vlpi(virq, &map);
if (ret)
goto out;
irq->hw = true;
irq->host_irq = virq;
out:
mutex_unlock(&its->its_lock);
return ret;
}
int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int virq,
struct kvm_kernel_irq_routing_entry *irq_entry)
{
struct vgic_its *its;
struct vgic_irq *irq;
int ret;
if (!vgic_supports_direct_msis(kvm))
return 0;
/*
* Get the ITS, and escape early on error (not a valid
* doorbell for any of our vITSs).
*/
its = vgic_get_its(kvm, irq_entry);
if (IS_ERR(its))
return 0;
mutex_lock(&its->its_lock);
ret = vgic_its_resolve_lpi(kvm, its, irq_entry->msi.devid,
irq_entry->msi.data, &irq);
if (ret)
goto out;
WARN_ON(!(irq->hw && irq->host_irq == virq));
irq->hw = false;
ret = its_unmap_vlpi(virq);
out:
mutex_unlock(&its->its_lock);
return ret;
}