KVM: add vm refcounting

the main purpose of adding this functions is the abilaty to release the
spinlock that protect the kvm list while still be able to do operations
on a specific kvm in a safe way.

Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index f4e143621e3..a2ceb51b427 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -114,6 +114,7 @@ struct kvm {
 	struct kvm_io_bus pio_bus;
 	struct kvm_vm_stat stat;
 	struct kvm_arch arch;
+	atomic_t users_count;
 };
 
 /* The guest did something we don't support. */
@@ -140,6 +141,9 @@ int kvm_init(void *opaque, unsigned int vcpu_size,
 		  struct module *module);
 void kvm_exit(void);
 
+void kvm_get_kvm(struct kvm *kvm);
+void kvm_put_kvm(struct kvm *kvm);
+
 #define HPA_MSB ((sizeof(hpa_t) * 8) - 1)
 #define HPA_ERR_MASK ((hpa_t)1 << HPA_MSB)
 static inline int is_error_hpa(hpa_t hpa) { return hpa >> HPA_MSB; }