KVM: Use a shared page for kernel/user communication when runing a vcpu
Instead of passing a 'struct kvm_run' back and forth between the kernel and
userspace, allocate a page and allow the user to mmap() it. This reduces
needless copying and makes the interface expandable by providing lots of
free space.
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index 0d122bf..901b8d9 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -228,6 +228,7 @@
struct mutex mutex;
int cpu;
int launched;
+ struct kvm_run *run;
int interrupt_window_open;
unsigned long irq_summary; /* bit vector: 1 per word in irq_pending */
#define NR_IRQ_WORDS KVM_IRQ_BITMAP_SIZE(unsigned long)