KVM: Add MSI-X interrupt injection logic

We have to handle more than one interrupt with one handler for MSI-X. Avi
suggested to use a flag to indicate the pending. So here is it.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Sheng Yang 2009-02-25 17:22:27 +08:00 committed by Avi Kivity
parent c1e0151429
commit 2350bd1f62
2 changed files with 60 additions and 7 deletions

View file

@ -319,6 +319,7 @@ struct kvm_irq_ack_notifier {
void (*irq_acked)(struct kvm_irq_ack_notifier *kian);
};
#define KVM_ASSIGNED_MSIX_PENDING 0x1
struct kvm_guest_msix_entry {
u32 vector;
u16 entry;

View file

@ -95,25 +95,69 @@ static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *h
return NULL;
}
static int find_index_from_host_irq(struct kvm_assigned_dev_kernel
*assigned_dev, int irq)
{
int i, index;
struct msix_entry *host_msix_entries;
host_msix_entries = assigned_dev->host_msix_entries;
index = -1;
for (i = 0; i < assigned_dev->entries_nr; i++)
if (irq == host_msix_entries[i].vector) {
index = i;
break;
}
if (index < 0) {
printk(KERN_WARNING "Fail to find correlated MSI-X entry!\n");
return 0;
}
return index;
}
static void kvm_assigned_dev_interrupt_work_handler(struct work_struct *work)
{
struct kvm_assigned_dev_kernel *assigned_dev;
struct kvm *kvm;
int irq, i;
assigned_dev = container_of(work, struct kvm_assigned_dev_kernel,
interrupt_work);
kvm = assigned_dev->kvm;
/* This is taken to safely inject irq inside the guest. When
* the interrupt injection (or the ioapic code) uses a
* 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_MSI) {
enable_irq(assigned_dev->host_irq);
assigned_dev->host_irq_disabled = false;
mutex_lock(&kvm->lock);
if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_MSIX) {
struct kvm_guest_msix_entry *guest_entries =
assigned_dev->guest_msix_entries;
for (i = 0; i < assigned_dev->entries_nr; i++) {
if (!(guest_entries[i].flags &
KVM_ASSIGNED_MSIX_PENDING))
continue;
guest_entries[i].flags &= ~KVM_ASSIGNED_MSIX_PENDING;
kvm_set_irq(assigned_dev->kvm,
assigned_dev->irq_source_id,
guest_entries[i].vector, 1);
irq = assigned_dev->host_msix_entries[i].vector;
if (irq != 0)
enable_irq(irq);
assigned_dev->host_irq_disabled = false;
}
} else {
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_MSI) {
enable_irq(assigned_dev->host_irq);
assigned_dev->host_irq_disabled = false;
}
}
mutex_unlock(&assigned_dev->kvm->lock);
}
@ -122,6 +166,14 @@ static irqreturn_t kvm_assigned_dev_intr(int irq, void *dev_id)
struct kvm_assigned_dev_kernel *assigned_dev =
(struct kvm_assigned_dev_kernel *) dev_id;
if (assigned_dev->irq_requested_type == KVM_ASSIGNED_DEV_MSIX) {
int index = find_index_from_host_irq(assigned_dev, irq);
if (index < 0)
return IRQ_HANDLED;
assigned_dev->guest_msix_entries[index].flags |=
KVM_ASSIGNED_MSIX_PENDING;
}
schedule_work(&assigned_dev->interrupt_work);
disable_irq_nosync(irq);