From 07975ad3b30579ca27d880491ad992326b930c63 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Thu, 29 Mar 2012 21:14:12 +0200 Subject: KVM: Introduce direct MSI message injection for in-kernel irqchips Currently, MSI messages can only be injected to in-kernel irqchips by defining a corresponding IRQ route for each message. This is not only unhandy if the MSI messages are generated "on the fly" by user space, IRQ routes are a limited resource that user space has to manage carefully. By providing a direct injection path, we can both avoid using up limited resources and simplify the necessary steps for user land. Signed-off-by: Jan Kiszka Signed-off-by: Avi Kivity --- virt/kvm/Kconfig | 3 +++ virt/kvm/irq_comm.c | 14 ++++++++++++++ virt/kvm/kvm_main.c | 14 ++++++++++++++ 3 files changed, 31 insertions(+) (limited to 'virt') diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index f63ccb0a5982..28694f4a9139 100644 --- a/virt/kvm/Kconfig +++ b/virt/kvm/Kconfig @@ -18,3 +18,6 @@ config KVM_MMIO config KVM_ASYNC_PF bool + +config HAVE_KVM_MSI + bool diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c index 9f614b4e365f..a6a0365475ed 100644 --- a/virt/kvm/irq_comm.c +++ b/virt/kvm/irq_comm.c @@ -138,6 +138,20 @@ int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, return kvm_irq_delivery_to_apic(kvm, NULL, &irq); } +int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi) +{ + struct kvm_kernel_irq_routing_entry route; + + if (!irqchip_in_kernel(kvm) || msi->flags != 0) + return -EINVAL; + + route.msi.address_lo = msi->address_lo; + route.msi.address_hi = msi->address_hi; + route.msi.data = msi->data; + + return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1); +} + /* * Return value: * < 0 Interrupt was ignored (masked or not delivered for other reasons) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 9eb7936e491d..1847c762d8d9 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2059,6 +2059,17 @@ static long kvm_vm_ioctl(struct file *filp, kvm->bsp_vcpu_id = arg; mutex_unlock(&kvm->lock); break; +#endif +#ifdef CONFIG_HAVE_KVM_MSI + case KVM_SIGNAL_MSI: { + struct kvm_msi msi; + + r = -EFAULT; + if (copy_from_user(&msi, argp, sizeof msi)) + goto out; + r = kvm_send_userspace_msi(kvm, &msi); + break; + } #endif default: r = kvm_arch_vm_ioctl(filp, ioctl, arg); @@ -2188,6 +2199,9 @@ static long kvm_dev_ioctl_check_extension_generic(long arg) case KVM_CAP_SET_BOOT_CPU_ID: #endif case KVM_CAP_INTERNAL_ERROR_DATA: +#ifdef CONFIG_HAVE_KVM_MSI + case KVM_CAP_SIGNAL_MSI: +#endif return 1; #ifdef CONFIG_HAVE_KVM_IRQCHIP case KVM_CAP_IRQ_ROUTING: -- cgit v1.2.3