intel_iommu: add support for split irqchip

In split irqchip mode, IOAPIC is working in user space, only update
kernel irq routes when entry changed. When IR is enabled, we directly
update the kernel with translated messages. It works just like a kernel
cache for the remapping entries.

Since KVM irqfd is using kernel gsi routes to deliver interrupts, as
long as we can support split irqchip, we will support irqfd as
well. Also, since kernel gsi routes will cache translated interrupts,
irqfd delivery will not suffer from any performance impact due to IR.

And, since we supported irqfd, vhost devices will be able to work
seamlessly with IR now. Logically this should contain both vhost-net and
vhost-user case.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[move trace-events lines into target-i386/trace-events]
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Peter Xu 2016-07-14 13:56:25 +08:00 committed by Michael S. Tsirkin
parent c15fa0bea9
commit 8b5ed7dffa
6 changed files with 45 additions and 0 deletions

View file

@ -35,6 +35,7 @@
#include "hw/i386/apic.h"
#include "hw/i386/apic_internal.h"
#include "hw/i386/apic-msidef.h"
#include "hw/i386/intel_iommu.h"
#include "exec/ioport.h"
#include "standard-headers/asm-x86/hyperv.h"
@ -42,6 +43,7 @@
#include "hw/pci/msi.h"
#include "migration/migration.h"
#include "exec/memattrs.h"
#include "trace.h"
//#define DEBUG_KVM
@ -3371,6 +3373,31 @@ int kvm_device_msix_deassign(KVMState *s, uint32_t dev_id)
int kvm_arch_fixup_msi_route(struct kvm_irq_routing_entry *route,
uint64_t address, uint32_t data, PCIDevice *dev)
{
X86IOMMUState *iommu = x86_iommu_get_default();
if (iommu) {
int ret;
MSIMessage src, dst;
X86IOMMUClass *class = X86_IOMMU_GET_CLASS(iommu);
src.address = route->u.msi.address_hi;
src.address <<= VTD_MSI_ADDR_HI_SHIFT;
src.address |= route->u.msi.address_lo;
src.data = route->u.msi.data;
ret = class->int_remap(iommu, &src, &dst, dev ? \
pci_requester_id(dev) : \
X86_IOMMU_SID_INVALID);
if (ret) {
trace_kvm_x86_fixup_msi_error(route->gsi);
return 1;
}
route->u.msi.address_hi = dst.address >> VTD_MSI_ADDR_HI_SHIFT;
route->u.msi.address_lo = dst.address & VTD_MSI_ADDR_LO_MASK;
route->u.msi.data = dst.data;
}
return 0;
}