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Diffstat (limited to 'arch/x86/kvm/i8259.c')
-rw-r--r--arch/x86/kvm/i8259.c52
1 files changed, 48 insertions, 4 deletions
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 17e41e165f1a..179dcb0103fd 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -26,10 +26,40 @@
* Port from Qemu.
*/
#include <linux/mm.h>
+#include <linux/bitops.h>
#include "irq.h"
#include <linux/kvm_host.h>
+static void pic_lock(struct kvm_pic *s)
+{
+ spin_lock(&s->lock);
+}
+
+static void pic_unlock(struct kvm_pic *s)
+{
+ struct kvm *kvm = s->kvm;
+ unsigned acks = s->pending_acks;
+ bool wakeup = s->wakeup_needed;
+ struct kvm_vcpu *vcpu;
+
+ s->pending_acks = 0;
+ s->wakeup_needed = false;
+
+ spin_unlock(&s->lock);
+
+ while (acks) {
+ kvm_notify_acked_irq(kvm, __ffs(acks));
+ acks &= acks - 1;
+ }
+
+ if (wakeup) {
+ vcpu = s->kvm->vcpus[0];
+ if (vcpu)
+ kvm_vcpu_kick(vcpu);
+ }
+}
+
static void pic_clear_isr(struct kvm_kpic_state *s, int irq)
{
s->isr &= ~(1 << irq);
@@ -136,17 +166,21 @@ static void pic_update_irq(struct kvm_pic *s)
void kvm_pic_update_irq(struct kvm_pic *s)
{
+ pic_lock(s);
pic_update_irq(s);
+ pic_unlock(s);
}
void kvm_pic_set_irq(void *opaque, int irq, int level)
{
struct kvm_pic *s = opaque;
+ pic_lock(s);
if (irq >= 0 && irq < PIC_NUM_PINS) {
pic_set_irq1(&s->pics[irq >> 3], irq & 7, level);
pic_update_irq(s);
}
+ pic_unlock(s);
}
/*
@@ -172,6 +206,7 @@ int kvm_pic_read_irq(struct kvm *kvm)
int irq, irq2, intno;
struct kvm_pic *s = pic_irqchip(kvm);
+ pic_lock(s);
irq = pic_get_irq(&s->pics[0]);
if (irq >= 0) {
pic_intack(&s->pics[0], irq);
@@ -196,6 +231,7 @@ int kvm_pic_read_irq(struct kvm *kvm)
intno = s->pics[0].irq_base + irq;
}
pic_update_irq(s);
+ pic_unlock(s);
kvm_notify_acked_irq(kvm, irq);
return intno;
@@ -203,7 +239,7 @@ int kvm_pic_read_irq(struct kvm *kvm)
void kvm_pic_reset(struct kvm_kpic_state *s)
{
- int irq, irqbase;
+ int irq, irqbase, n;
struct kvm *kvm = s->pics_state->irq_request_opaque;
struct kvm_vcpu *vcpu0 = kvm->vcpus[0];
@@ -214,8 +250,10 @@ void kvm_pic_reset(struct kvm_kpic_state *s)
for (irq = 0; irq < PIC_NUM_PINS/2; irq++) {
if (vcpu0 && kvm_apic_accept_pic_intr(vcpu0))
- if (s->irr & (1 << irq) || s->isr & (1 << irq))
- kvm_notify_acked_irq(kvm, irq+irqbase);
+ if (s->irr & (1 << irq) || s->isr & (1 << irq)) {
+ n = irq + irqbase;
+ s->pics_state->pending_acks |= 1 << n;
+ }
}
s->last_irr = 0;
s->irr = 0;
@@ -406,6 +444,7 @@ static void picdev_write(struct kvm_io_device *this,
printk(KERN_ERR "PIC: non byte write\n");
return;
}
+ pic_lock(s);
switch (addr) {
case 0x20:
case 0x21:
@@ -418,6 +457,7 @@ static void picdev_write(struct kvm_io_device *this,
elcr_ioport_write(&s->pics[addr & 1], addr, data);
break;
}
+ pic_unlock(s);
}
static void picdev_read(struct kvm_io_device *this,
@@ -431,6 +471,7 @@ static void picdev_read(struct kvm_io_device *this,
printk(KERN_ERR "PIC: non byte read\n");
return;
}
+ pic_lock(s);
switch (addr) {
case 0x20:
case 0x21:
@@ -444,6 +485,7 @@ static void picdev_read(struct kvm_io_device *this,
break;
}
*(unsigned char *)val = data;
+ pic_unlock(s);
}
/*
@@ -459,7 +501,7 @@ static void pic_irq_request(void *opaque, int level)
s->output = level;
if (vcpu && level && (s->pics[0].isr_ack & (1 << irq))) {
s->pics[0].isr_ack &= ~(1 << irq);
- kvm_vcpu_kick(vcpu);
+ s->wakeup_needed = true;
}
}
@@ -469,6 +511,8 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)
s = kzalloc(sizeof(struct kvm_pic), GFP_KERNEL);
if (!s)
return NULL;
+ spin_lock_init(&s->lock);
+ s->kvm = kvm;
s->pics[0].elcr_mask = 0xf8;
s->pics[1].elcr_mask = 0xde;
s->irq_request = pic_irq_request;