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authorSheng Yang <sheng@linux.intel.com>2009-02-25 17:22:28 +0800
committerAvi Kivity <avi@redhat.com>2009-06-10 11:48:23 +0300
commitd510d6cc653bc4b3094ea73afe12600d0ab445b3 (patch)
tree60ea170465dcddcd5cdd7c29a29df3f28407c202 /virt
parent2350bd1f62c8706c22b8e58c3bfff10806c0a31b (diff)
downloadlinux-linaro-stable-d510d6cc653bc4b3094ea73afe12600d0ab445b3.tar.gz
KVM: Enable MSI-X for KVM assigned device
This patch finally enable MSI-X. What we need for MSI-X: 1. Intercept one page in MMIO region of device. So that we can get guest desired MSI-X table and set up the real one. Now this have been done by guest, and transfer to kernel using ioctl KVM_SET_MSIX_NR and KVM_SET_MSIX_ENTRY. 2. Information for incoming interrupt. Now one device can have more than one interrupt, and they are all handled by one workqueue structure. So we need to identify them. The previous patch enable gsi_msg_pending_bitmap get this done. 3. Mapping from host IRQ to guest gsi as well as guest gsi to real MSI/MSI-X message address/data. We used same entry number for the host and guest here, so that it's easy to find the correlated guest gsi. What we lack for now: 1. The PCI spec said nothing can existed with MSI-X table in the same page of MMIO region, except pending bits. The patch ignore pending bits as the first step (so they are always 0 - no pending). 2. The PCI spec allowed to change MSI-X table dynamically. That means, the OS can enable MSI-X, then mask one MSI-X entry, modify it, and unmask it. The patch didn't support this, and Linux also don't work in this way. 3. The patch didn't implement MSI-X mask all and mask single entry. I would implement the former in driver/pci/msi.c later. And for single entry, userspace should have reposibility to handle it. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'virt')
-rw-r--r--virt/kvm/kvm_main.c98
1 files changed, 92 insertions, 6 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 8bd44d6985c7..3bed82754a5d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -236,13 +236,33 @@ static void kvm_free_assigned_irq(struct kvm *kvm,
* now, the kvm state is still legal for probably we also have to wait
* interrupt_work done.
*/
- disable_irq_nosync(assigned_dev->host_irq);
- cancel_work_sync(&assigned_dev->interrupt_work);
+ if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_MSIX) {
+ int i;
+ for (i = 0; i < assigned_dev->entries_nr; i++)
+ disable_irq_nosync(assigned_dev->
+ host_msix_entries[i].vector);
+
+ cancel_work_sync(&assigned_dev->interrupt_work);
- free_irq(assigned_dev->host_irq, (void *)assigned_dev);
+ for (i = 0; i < assigned_dev->entries_nr; i++)
+ free_irq(assigned_dev->host_msix_entries[i].vector,
+ (void *)assigned_dev);
- if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI)
- pci_disable_msi(assigned_dev->dev);
+ assigned_dev->entries_nr = 0;
+ kfree(assigned_dev->host_msix_entries);
+ kfree(assigned_dev->guest_msix_entries);
+ pci_disable_msix(assigned_dev->dev);
+ } else {
+ /* Deal with MSI and INTx */
+ disable_irq_nosync(assigned_dev->host_irq);
+ cancel_work_sync(&assigned_dev->interrupt_work);
+
+ 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);
+ }
assigned_dev->irq_requested_type = 0;
}
@@ -373,6 +393,60 @@ static int assigned_device_update_msi(struct kvm *kvm,
}
#endif
+#ifdef __KVM_HAVE_MSIX
+static int assigned_device_update_msix(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *adev,
+ struct kvm_assigned_irq *airq)
+{
+ /* TODO Deal with KVM_DEV_IRQ_ASSIGNED_MASK_MSIX */
+ int i, r;
+
+ adev->ack_notifier.gsi = -1;
+
+ if (irqchip_in_kernel(kvm)) {
+ if (airq->flags & KVM_DEV_IRQ_ASSIGN_MASK_MSIX)
+ return -ENOTTY;
+
+ if (!(airq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSIX)) {
+ /* Guest disable MSI-X */
+ kvm_free_assigned_irq(kvm, adev);
+ if (msi2intx) {
+ pci_enable_msi(adev->dev);
+ if (adev->dev->msi_enabled)
+ return assigned_device_update_msi(kvm,
+ adev, airq);
+ }
+ return assigned_device_update_intx(kvm, adev, airq);
+ }
+
+ /* host_msix_entries and guest_msix_entries should have been
+ * initialized */
+ if (adev->entries_nr == 0)
+ return -EINVAL;
+
+ kvm_free_assigned_irq(kvm, adev);
+
+ r = pci_enable_msix(adev->dev, adev->host_msix_entries,
+ adev->entries_nr);
+ if (r)
+ return r;
+
+ for (i = 0; i < adev->entries_nr; i++) {
+ r = request_irq((adev->host_msix_entries + i)->vector,
+ kvm_assigned_dev_intr, 0,
+ "kvm_assigned_msix_device",
+ (void *)adev);
+ if (r)
+ return r;
+ }
+ }
+
+ adev->irq_requested_type |= KVM_ASSIGNED_DEV_MSIX;
+
+ return 0;
+}
+#endif
+
static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
struct kvm_assigned_irq
*assigned_irq)
@@ -417,12 +491,24 @@ static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
}
}
- if ((match->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) &&
+ if (match->irq_requested_type & KVM_ASSIGNED_DEV_MSIX)
+ current_flags |= KVM_DEV_IRQ_ASSIGN_ENABLE_MSIX;
+ else if ((match->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) &&
(match->irq_requested_type & KVM_ASSIGNED_DEV_GUEST_MSI))
current_flags |= KVM_DEV_IRQ_ASSIGN_ENABLE_MSI;
changed_flags = assigned_irq->flags ^ current_flags;
+#ifdef __KVM_HAVE_MSIX
+ if (changed_flags & KVM_DEV_IRQ_ASSIGN_MSIX_ACTION) {
+ r = assigned_device_update_msix(kvm, match, assigned_irq);
+ if (r) {
+ printk(KERN_WARNING "kvm: failed to execute "
+ "MSI-X action!\n");
+ goto out_release;
+ }
+ } else
+#endif
if ((changed_flags & KVM_DEV_IRQ_ASSIGN_MSI_ACTION) ||
(msi2intx && match->dev->msi_enabled)) {
#ifdef CONFIG_X86