From 6b9cc7fd469869bed38831c5adac3f59dc25eaf5 Mon Sep 17 00:00:00 2001 From: Sheng Yang Date: Mon, 24 Nov 2008 14:32:56 +0800 Subject: [PATCH] KVM: Enable MSI for device assignment We enable guest MSI and host MSI support in this patch. The userspace want to enable MSI should set KVM_DEV_IRQ_ASSIGN_ENABLE_MSI in the assigned_irq's flag. Function would return -ENOTTY if can't enable MSI, userspace shouldn't set MSI Enable bit when KVM_ASSIGN_IRQ return -ENOTTY with KVM_DEV_IRQ_ASSIGN_ENABLE_MSI. Userspace can tell the support of MSI device from #ifdef KVM_CAP_DEVICE_MSI. Signed-off-by: Sheng Yang Signed-off-by: Avi Kivity --- include/linux/kvm.h | 3 ++ virt/kvm/kvm_main.c | 81 +++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 78 insertions(+), 6 deletions(-) diff --git a/include/linux/kvm.h b/include/linux/kvm.h index bb283c388a24..0997e6f5490c 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -392,6 +392,9 @@ struct kvm_trace_rec { #endif #define KVM_CAP_IOMMU 18 #define KVM_CAP_NMI 19 +#if defined(CONFIG_X86) +#define KVM_CAP_DEVICE_MSI 20 +#endif /* * ioctls for VM fds diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 228c1d18a614..bf36ae9ae7df 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -159,9 +159,15 @@ static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work) * finer-grained lock, update this */ mutex_lock(&assigned_dev->kvm->lock); - kvm_set_irq(assigned_dev->kvm, - assigned_dev->irq_source_id, - assigned_dev->guest_irq, 1); + if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_GUEST_INTX) + kvm_set_irq(assigned_dev->kvm, + assigned_dev->irq_source_id, + assigned_dev->guest_irq, 1); + else if (assigned_dev->irq_requested_type & + KVM_ASSIGNED_DEV_GUEST_MSI) { + assigned_device_msi_dispatch(assigned_dev); + enable_irq(assigned_dev->host_irq); + } mutex_unlock(&assigned_dev->kvm->lock); kvm_put_kvm(assigned_dev->kvm); } @@ -197,6 +203,8 @@ static void kvm_free_assigned_device(struct kvm *kvm, { if (irqchip_in_kernel(kvm) && assigned_dev->irq_requested_type) free_irq(assigned_dev->host_irq, (void *)assigned_dev); + if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) + pci_disable_msi(assigned_dev->dev); kvm_unregister_irq_ack_notifier(&assigned_dev->ack_notifier); kvm_free_irq_source_id(kvm, assigned_dev->irq_source_id); @@ -242,6 +250,11 @@ static int assigned_device_update_intx(struct kvm *kvm, return 0; if (irqchip_in_kernel(kvm)) { + if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) { + free_irq(adev->host_irq, (void *)kvm); + pci_disable_msi(adev->dev); + } + if (!capable(CAP_SYS_RAWIO)) return -EPERM; @@ -265,6 +278,41 @@ static int assigned_device_update_intx(struct kvm *kvm, return 0; } +#ifdef CONFIG_X86 +static int assigned_device_update_msi(struct kvm *kvm, + struct kvm_assigned_dev_kernel *adev, + struct kvm_assigned_irq *airq) +{ + int r; + + /* x86 don't care upper address of guest msi message addr */ + adev->guest_msi.address_lo = airq->guest_msi.addr_lo; + adev->guest_msi.data = airq->guest_msi.data; + adev->ack_notifier.gsi = -1; + + if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) + return 0; + + if (irqchip_in_kernel(kvm)) { + if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_INTX) + free_irq(adev->host_irq, (void *)adev); + + r = pci_enable_msi(adev->dev); + if (r) + return r; + + adev->host_irq = adev->dev->irq; + if (request_irq(adev->host_irq, kvm_assigned_dev_intr, 0, + "kvm_assigned_msi_device", (void *)adev)) + return -EIO; + } + + adev->irq_requested_type = KVM_ASSIGNED_DEV_GUEST_MSI | + KVM_ASSIGNED_DEV_HOST_MSI; + return 0; +} +#endif + static int kvm_vm_ioctl_assign_irq(struct kvm *kvm, struct kvm_assigned_irq *assigned_irq) @@ -301,9 +349,30 @@ static int kvm_vm_ioctl_assign_irq(struct kvm *kvm, } } - r = assigned_device_update_intx(kvm, match, assigned_irq); - if (r) - goto out_release; + if (assigned_irq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI) { +#ifdef CONFIG_X86 + r = assigned_device_update_msi(kvm, match, assigned_irq); + if (r) { + printk(KERN_WARNING "kvm: failed to enable " + "MSI device!\n"); + goto out_release; + } +#else + r = -ENOTTY; +#endif + } else if (assigned_irq->host_irq == 0 && match->dev->irq == 0) { + /* Host device IRQ 0 means don't support INTx */ + printk(KERN_WARNING "kvm: wait device to enable MSI!\n"); + r = 0; + } else { + /* Non-sharing INTx mode */ + r = assigned_device_update_intx(kvm, match, assigned_irq); + if (r) { + printk(KERN_WARNING "kvm: failed to enable " + "INTx device!\n"); + goto out_release; + } + } mutex_unlock(&kvm->lock); return r;