KVM: Ioctls for init MSI-X entry
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>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 4d0dd39..1ceb969 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1593,6 +1593,88 @@
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 @@
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);
}