Hi Sheng, On Wed, Feb 11, 2009 at 04:08:50PM +0800, Sheng Yang wrote: > We have to handle more than one interrupt with one handler for MSI-X. So we > need a bitmap to track the triggered interrupts. > > Signed-off-by: Sheng Yang <sheng@xxxxxxxxxxxxxxx> > --- > include/linux/kvm_host.h | 5 +- > virt/kvm/kvm_main.c | 103 ++++++++++++++++++++++++++++++++++++++++++++- > 2 files changed, 103 insertions(+), 5 deletions(-) > > @@ -335,6 +337,7 @@ struct kvm_assigned_dev_kernel { > #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)) Can you explain the usage of the two bits? > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index ea96690..961603f 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -95,25 +95,113 @@ static struct kvm_assigned_dev_kernel *kvm_find_assigned_dev(struct list_head *h > return NULL; > } > > +static int find_host_irq_from_gsi(struct kvm_assigned_dev_kernel *assigned_dev, > + u32 gsi) > +{ > + int i, entry, irq; > + struct msix_entry *host_msix_entries, *guest_msix_entries; > + > + host_msix_entries = assigned_dev->host_msix_entries; > + guest_msix_entries = assigned_dev->guest_msix_entries; > + > + entry = -1; > + irq = 0; > + for (i = 0; i < assigned_dev->entries_nr; i++) > + if (gsi == (guest_msix_entries + i)->vector) { > + entry = (guest_msix_entries + i)->entry; > + break; > + } > + if (entry < 0) { > + printk(KERN_WARNING "Fail to find correlated MSI-X entry!\n"); > + return 0; > + } > + for (i = 0; i < assigned_dev->entries_nr; i++) > + if (entry == (host_msix_entries + i)->entry) { > + irq = (host_msix_entries + i)->vector; > + break; > + } > + if (irq == 0) { > + printk(KERN_WARNING "Fail to find correlated MSI-X irq!\n"); > + return 0; > + } Can drop the printk's (also from find_gsi_from_host_irq). > struct kvm_assigned_dev_kernel *assigned_dev; > + struct kvm *kvm; > + u32 gsi; > + int irq; > > 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); > + mutex_lock(&kvm->lock); > +handle_irq: > + if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_MSIX) { > + gsi = find_first_bit(kvm->irq_routes_pending_bitmap, > + KVM_MAX_IRQ_ROUTES); > + BUG_ON(gsi >= KVM_MAX_IRQ_ROUTES); > + clear_bit(gsi, kvm->irq_routes_pending_bitmap); > + } else > + gsi = assigned_dev->guest_irq; > + > + kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id, gsi, 1); > > if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_GUEST_MSI) { > enable_irq(assigned_dev->host_irq); > assigned_dev->host_irq_disabled = false; > + } else if (assigned_dev->irq_requested_type & KVM_ASSIGNED_DEV_MSIX) { > + irq = find_host_irq_from_gsi(assigned_dev, gsi); Check the return value? > + enable_irq(irq); Do you guarantee that particular irq you're enable_irq'ing is not bogus? Its has been passed from userspace after all. In a later patch you can assign KVM_ASSIGNED_DEV_MSIX if the irqchip is not in-kernel in assigned_device_update_msix: + adev->irq_requested_type |= KVM_ASSIGNED_DEV_MSIX; + Just trying to harden the code against bogosity elsewhere. > + assigned_dev->host_irq_disabled = false; > + gsi = find_first_bit(kvm->irq_routes_pending_bitmap, > + KVM_MAX_IRQ_ROUTES); > + if (gsi < KVM_MAX_IRQ_ROUTES) > + goto handle_irq; > } > + > mutex_unlock(&assigned_dev->kvm->lock); > } > > @@ -121,6 +209,15 @@ 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; > + struct kvm *kvm = assigned_dev->kvm; > + > + if (assigned_dev->irq_requested_type == KVM_ASSIGNED_DEV_MSIX) { > + u32 gsi; > + gsi = find_gsi_from_host_irq(assigned_dev, irq); > + if (gsi == 0) > + return IRQ_HANDLED; So you chose GSI == 0 as invalid because of x86 assumptions? Or is there any other reason? IRQ sharing in the host side is not supported correct? -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html