Now we use MSI as default one, and translate MSI to INTx when guest need
INTx rather than MSI. For legacy device, we provide support for non-sharing
host IRQ.

Provide a parameter msi2intx for this method. The value is true by default.

Signed-off-by: Sheng Yang <[EMAIL PROTECTED]>
---
 virt/kvm/kvm_main.c |   67 ++++++++++++++++++++++++++++++++++++++------------
 1 files changed, 51 insertions(+), 16 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 8e0b599..98f145d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -64,6 +64,9 @@
 MODULE_AUTHOR("Qumranet");
 MODULE_LICENSE("GPL");
 
+static int msi2intx = 1;
+module_param(msi2intx, bool, 0);
+
 DEFINE_SPINLOCK(kvm_lock);
 LIST_HEAD(vm_list);
 
@@ -249,7 +252,8 @@ 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) {
+               if (!msi2intx &&
+                   adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) {
                        free_irq(adev->host_irq, (void *)kvm);
                        pci_disable_msi(adev->dev);
                }
@@ -284,21 +288,33 @@ static int assigned_device_update_msi(struct kvm *kvm,
 {
        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 (airq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI) {
+               /* x86 don't care upper address of guest msi message addr */
+               adev->irq_requested_type |= KVM_ASSIGNED_DEV_GUEST_MSI;
+               adev->irq_requested_type &= ~KVM_ASSIGNED_DEV_GUEST_INTX;
+               adev->guest_msi.address_lo = airq->guest_msi.addr_lo;
+               adev->guest_msi.data = airq->guest_msi.data;
+               adev->ack_notifier.gsi = -1;
+       } else if (msi2intx) {
+               adev->irq_requested_type |= KVM_ASSIGNED_DEV_GUEST_INTX;
+               adev->irq_requested_type &= ~KVM_ASSIGNED_DEV_GUEST_MSI;
+               adev->guest_irq = airq->guest_irq;
+               adev->ack_notifier.gsi = airq->guest_irq;
+       }
 
        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;
+               if (!msi2intx) {
+                       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,
@@ -306,8 +322,10 @@ static int assigned_device_update_msi(struct kvm *kvm,
                        return -EIO;
        }
 
-       adev->irq_requested_type = KVM_ASSIGNED_DEV_GUEST_MSI |
-                                  KVM_ASSIGNED_DEV_HOST_MSI;
+       if (!msi2intx)
+               adev->irq_requested_type = KVM_ASSIGNED_DEV_GUEST_MSI;
+
+       adev->irq_requested_type |= KVM_ASSIGNED_DEV_HOST_MSI;
        return 0;
 }
 #endif
@@ -345,10 +363,19 @@ static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
                                goto out_release;
                        else
                                match->irq_source_id = r;
+
+#ifdef CONFIG_X86
+                       /* Determine host device irq type, we can know the
+                        * result from dev->msi_enabled */
+                       if (msi2intx)
+                               pci_enable_msi(match->dev);
+#endif
                }
        }
 
-       if (assigned_irq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI) {
+       if ((!msi2intx &&
+            (assigned_irq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI)) ||
+           (msi2intx && match->dev->msi_enabled)) {
 #ifdef CONFIG_X86
                r = assigned_device_update_msi(kvm, match, assigned_irq);
                if (r) {
@@ -361,8 +388,16 @@ static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
 #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;
+               if (!msi2intx) {
+                       printk(KERN_WARNING
+                              "kvm: wait device to enable MSI!\n");
+                       r = 0;
+               } else {
+                       printk(KERN_WARNING
+                              "kvm: failed to enable MSI device!\n");
+                       r = -ENOTTY;
+                       goto out_release;
+               }
        } else {
                /* Non-sharing INTx mode */
                r = assigned_device_update_intx(kvm, match, assigned_irq);
-- 
1.5.4.5

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to