From 174178fed338edba66ab9580af0c5d9e1a4e5019 Mon Sep 17 00:00:00 2001 From: Eric Auger Date: Wed, 4 Mar 2015 11:14:36 +0100 Subject: KVM: arm/arm64: add irqfd support This patch enables irqfd on arm/arm64. Both irqfd and resamplefd are supported. Injection is implemented in vgic.c without routing. This patch enables CONFIG_HAVE_KVM_EVENTFD and CONFIG_HAVE_KVM_IRQFD. KVM_CAP_IRQFD is now advertised. KVM_CAP_IRQFD_RESAMPLE capability automatically is advertised as soon as CONFIG_HAVE_KVM_IRQFD is set. Irqfd injection is restricted to SPI. The rationale behind not supporting PPI irqfd injection is that any device using a PPI would be a private-to-the-CPU device (timer for instance), so its state would have to be context-switched along with the VCPU and would require in-kernel wiring anyhow. It is not a relevant use case for irqfds. Signed-off-by: Eric Auger Reviewed-by: Christoffer Dall Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall --- Documentation/virtual/kvm/api.txt | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'Documentation/virtual') diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index b112efc816f1..b265d8e50be0 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2234,7 +2234,7 @@ into the hash PTE second double word). 4.75 KVM_IRQFD Capability: KVM_CAP_IRQFD -Architectures: x86 s390 +Architectures: x86 s390 arm arm64 Type: vm ioctl Parameters: struct kvm_irqfd (in) Returns: 0 on success, -1 on error @@ -2260,6 +2260,10 @@ Note that closing the resamplefd is not sufficient to disable the irqfd. The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment and need not be specified with KVM_IRQFD_FLAG_DEASSIGN. +On ARM/ARM64, the gsi field in the kvm_irqfd struct specifies the Shared +Peripheral Interrupt (SPI) index, such that the GIC interrupt ID is +given by gsi + 32. + 4.76 KVM_PPC_ALLOCATE_HTAB Capability: KVM_CAP_PPC_ALLOC_HTAB -- cgit v1.2.3