KVM: Ioctls for init MSI-X entry
Sheng Yang [Wed, 25 Feb 2009 09:22:26 +0000 (17:22 +0800)]
Introduce KVM_SET_MSIX_NR and KVM_SET_MSIX_ENTRY two ioctls.

This two ioctls are used by userspace to specific guest device MSI-X entry
number and correlate MSI-X entry with GSI during the initialization stage.

MSI-X should be well initialzed before enabling.

Don't support change MSI-X entry number for now.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

include/linux/kvm.h
include/linux/kvm_host.h
virt/kvm/kvm_main.c

index 8cc1379..78cdee8 100644 (file)
@@ -487,6 +487,10 @@ struct kvm_irq_routing {
 #define KVM_REINJECT_CONTROL      _IO(KVMIO, 0x71)
 #define KVM_DEASSIGN_PCI_DEVICE _IOW(KVMIO, 0x72, \
                                     struct kvm_assigned_pci_dev)
+#define KVM_ASSIGN_SET_MSIX_NR \
+                       _IOW(KVMIO, 0x73, struct kvm_assigned_msix_nr)
+#define KVM_ASSIGN_SET_MSIX_ENTRY \
+                       _IOW(KVMIO, 0x74, struct kvm_assigned_msix_entry)
 
 /*
  * ioctls for vcpu fds
@@ -607,4 +611,18 @@ struct kvm_assigned_irq {
 #define KVM_DEV_IRQ_ASSIGN_MSI_ACTION  KVM_DEV_IRQ_ASSIGN_ENABLE_MSI
 #define KVM_DEV_IRQ_ASSIGN_ENABLE_MSI  (1 << 0)
 
+struct kvm_assigned_msix_nr {
+       __u32 assigned_dev_id;
+       __u16 entry_nr;
+       __u16 padding;
+};
+
+#define KVM_MAX_MSIX_PER_DEV           512
+struct kvm_assigned_msix_entry {
+       __u32 assigned_dev_id;
+       __u32 gsi;
+       __u16 entry; /* The index of entry in the MSI-X table */
+       __u16 padding[3];
+};
+
 #endif
index 1a2f98f..432edc2 100644 (file)
@@ -319,6 +319,12 @@ struct kvm_irq_ack_notifier {
        void (*irq_acked)(struct kvm_irq_ack_notifier *kian);
 };
 
+struct kvm_guest_msix_entry {
+       u32 vector;
+       u16 entry;
+       u16 flags;
+};
+
 struct kvm_assigned_dev_kernel {
        struct kvm_irq_ack_notifier ack_notifier;
        struct work_struct interrupt_work;
@@ -326,13 +332,17 @@ struct kvm_assigned_dev_kernel {
        int assigned_dev_id;
        int host_busnr;
        int host_devfn;
+       unsigned int entries_nr;
        int host_irq;
        bool host_irq_disabled;
+       struct msix_entry *host_msix_entries;
        int guest_irq;
+       struct kvm_guest_msix_entry *guest_msix_entries;
 #define KVM_ASSIGNED_DEV_GUEST_INTX    (1 << 0)
 #define KVM_ASSIGNED_DEV_GUEST_MSI     (1 << 1)
 #define KVM_ASSIGNED_DEV_HOST_INTX     (1 << 8)
 #define KVM_ASSIGNED_DEV_HOST_MSI      (1 << 9)
+#define KVM_ASSIGNED_DEV_MSIX          ((1 << 2) | (1 << 10))
        unsigned long irq_requested_type;
        int irq_source_id;
        int flags;
index 4d0dd39..1ceb969 100644 (file)
@@ -1593,6 +1593,88 @@ static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
        return 0;
 }
 
+#ifdef __KVM_HAVE_MSIX
+static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
+                                   struct kvm_assigned_msix_nr *entry_nr)
+{
+       int r = 0;
+       struct kvm_assigned_dev_kernel *adev;
+
+       mutex_lock(&kvm->lock);
+
+       adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
+                                     entry_nr->assigned_dev_id);
+       if (!adev) {
+               r = -EINVAL;
+               goto msix_nr_out;
+       }
+
+       if (adev->entries_nr == 0) {
+               adev->entries_nr = entry_nr->entry_nr;
+               if (adev->entries_nr == 0 ||
+                   adev->entries_nr >= KVM_MAX_MSIX_PER_DEV) {
+                       r = -EINVAL;
+                       goto msix_nr_out;
+               }
+
+               adev->host_msix_entries = kzalloc(sizeof(struct msix_entry) *
+                                               entry_nr->entry_nr,
+                                               GFP_KERNEL);
+               if (!adev->host_msix_entries) {
+                       r = -ENOMEM;
+                       goto msix_nr_out;
+               }
+               adev->guest_msix_entries = kzalloc(
+                               sizeof(struct kvm_guest_msix_entry) *
+                               entry_nr->entry_nr, GFP_KERNEL);
+               if (!adev->guest_msix_entries) {
+                       kfree(adev->host_msix_entries);
+                       r = -ENOMEM;
+                       goto msix_nr_out;
+               }
+       } else /* Not allowed set MSI-X number twice */
+               r = -EINVAL;
+msix_nr_out:
+       mutex_unlock(&kvm->lock);
+       return r;
+}
+
+static int kvm_vm_ioctl_set_msix_entry(struct kvm *kvm,
+                                      struct kvm_assigned_msix_entry *entry)
+{
+       int r = 0, i;
+       struct kvm_assigned_dev_kernel *adev;
+
+       mutex_lock(&kvm->lock);
+
+       adev = kvm_find_assigned_dev(&kvm->arch.assigned_dev_head,
+                                     entry->assigned_dev_id);
+
+       if (!adev) {
+               r = -EINVAL;
+               goto msix_entry_out;
+       }
+
+       for (i = 0; i < adev->entries_nr; i++)
+               if (adev->guest_msix_entries[i].vector == 0 ||
+                   adev->guest_msix_entries[i].entry == entry->entry) {
+                       adev->guest_msix_entries[i].entry = entry->entry;
+                       adev->guest_msix_entries[i].vector = entry->gsi;
+                       adev->host_msix_entries[i].entry = entry->entry;
+                       break;
+               }
+       if (i == adev->entries_nr) {
+               r = -ENOSPC;
+               goto msix_entry_out;
+       }
+
+msix_entry_out:
+       mutex_unlock(&kvm->lock);
+
+       return r;
+}
+#endif
+
 static long kvm_vcpu_ioctl(struct file *filp,
                           unsigned int ioctl, unsigned long arg)
 {
@@ -1917,7 +1999,29 @@ static long kvm_vm_ioctl(struct file *filp,
                vfree(entries);
                break;
        }
+#ifdef __KVM_HAVE_MSIX
+       case KVM_ASSIGN_SET_MSIX_NR: {
+               struct kvm_assigned_msix_nr entry_nr;
+               r = -EFAULT;
+               if (copy_from_user(&entry_nr, argp, sizeof entry_nr))
+                       goto out;
+               r = kvm_vm_ioctl_set_msix_nr(kvm, &entry_nr);
+               if (r)
+                       goto out;
+               break;
+       }
+       case KVM_ASSIGN_SET_MSIX_ENTRY: {
+               struct kvm_assigned_msix_entry entry;
+               r = -EFAULT;
+               if (copy_from_user(&entry, argp, sizeof entry))
+                       goto out;
+               r = kvm_vm_ioctl_set_msix_entry(kvm, &entry);
+               if (r)
+                       goto out;
+               break;
+       }
 #endif
+#endif /* KVM_CAP_IRQ_ROUTING */
        default:
                r = kvm_arch_vm_ioctl(filp, ioctl, arg);
        }