KVM: Move irq sharing information to irqchip level

This removes assumptions that max GSIs is smaller than number of pins.
Sharing is tracked on pin level not GSI level.

[avi: no PIC on ia64]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

2 files changed, 37 insertions, 23 deletions

diff --git a/virt/kvm/ioapic.h b/virt/kvm/ioapic.h
index 7080b713c16..6e461ade636 100644
--- a/virt/kvm/ioapic.h
+++ b/virt/kvm/ioapic.h
@@ -41,6 +41,7 @@ struct kvm_ioapic {
         u32 irr;
         u32 pad;
         union kvm_ioapic_redirect_entry redirtbl[IOAPIC_NUM_PINS];
+        unsigned long irq_states[IOAPIC_NUM_PINS];
         struct kvm_io_device dev;
         struct kvm *kvm;
         void (*ack_notifier)(void *opaque, int irq);
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index 001663ff401..9783f5c43da 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -31,20 +31,39 @@
 
 #include "ioapic.h"
 
+static inline int kvm_irq_line_state(unsigned long *irq_state,
+                                     int irq_source_id, int level)
+{
+        /* Logical OR for level trig interrupt */
+        if (level)
+                set_bit(irq_source_id, irq_state);
+        else
+                clear_bit(irq_source_id, irq_state);
+
+        return !!(*irq_state);
+}
+
 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
-                           struct kvm *kvm, int level)
+                           struct kvm *kvm, int irq_source_id, int level)
 {
 #ifdef CONFIG_X86
-        return kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level);
+        struct kvm_pic *pic = pic_irqchip(kvm);
+        level = kvm_irq_line_state(&pic->irq_states[e->irqchip.pin],
+                                   irq_source_id, level);
+        return kvm_pic_set_irq(pic, e->irqchip.pin, level);
 #else
         return -1;
 #endif
 }
 
 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
-                              struct kvm *kvm, int level)
+                              struct kvm *kvm, int irq_source_id, int level)
 {
-        return kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level);
+        struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+        level = kvm_irq_line_state(&ioapic->irq_states[e->irqchip.pin],
+                                   irq_source_id, level);
+
+        return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, level);
 }
 
 inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
@@ -96,10 +115,13 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
 }
 
 static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
-                       struct kvm *kvm, int level)
+                       struct kvm *kvm, int irq_source_id, int level)
 {
         struct kvm_lapic_irq irq;
 
+        if (!level)
+                return -1;
+
         trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
 
         irq.dest_id = (e->msi.address_lo &
@@ -125,34 +147,19 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
 int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
 {
         struct kvm_kernel_irq_routing_entry *e;
-        unsigned long *irq_state, sig_level;
         int ret = -1;
 
         trace_kvm_set_irq(irq, level, irq_source_id);
 
         WARN_ON(!mutex_is_locked(&kvm->irq_lock));
 
-        if (irq < KVM_IOAPIC_NUM_PINS) {
-                irq_state = (unsigned long *)&kvm->arch.irq_states[irq];
-
-                /* Logical OR for level trig interrupt */
-                if (level)
-                        set_bit(irq_source_id, irq_state);
-                else
-                        clear_bit(irq_source_id, irq_state);
-                sig_level = !!(*irq_state);
-        } else if (!level)
-                return ret;
-        else /* Deal with MSI/MSI-X */
-                sig_level = 1;
-
         /* Not possible to detect if the guest uses the PIC or the
          * IOAPIC.  So set the bit in both. The guest will ignore
          * writes to the unused one.
          */
         list_for_each_entry(e, &kvm->irq_routing, link)
                 if (e->gsi == irq) {
-                        int r = e->set(e, kvm, sig_level);
+                        int r = e->set(e, kvm, irq_source_id, level);
                         if (r < 0)
                                 continue;
 
@@ -232,8 +239,14 @@ void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
                 return;
         }
-        for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
-                clear_bit(irq_source_id, &kvm->arch.irq_states[i]);
+        for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++) {
+                clear_bit(irq_source_id, &kvm->arch.vioapic->irq_states[i]);
+                if (i >= 16)
+                        continue;
+#ifdef CONFIG_X86
+                clear_bit(irq_source_id, &pic_irqchip(kvm)->irq_states[i]);
+#endif
+        }
         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
         mutex_unlock(&kvm->irq_lock);
 }