KVM: rename hardware_[dis|en]able() to *_nolock() and add locking wrappers

The naming convension of hardware_[dis|en]able family is little bit confusing
because only hardware_[dis|en]able_all are using _nolock suffix.

Renaming current hardware_[dis|en]able() to *_nolock() and using
hardware_[dis|en]able() as wrapper functions which take kvm_lock for them
reduces extra confusion.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 22 insertions, 12 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f69fca7a88b5..5156d458a84d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2059,7 +2059,7 @@ static struct miscdevice kvm_dev = {
         &kvm_chardev_ops,
 };
 
-static void hardware_enable(void *junk)
+static void hardware_enable_nolock(void *junk)
 {
         int cpu = raw_smp_processor_id();
         int r;
@@ -2079,7 +2079,14 @@ static void hardware_enable(void *junk)
         }
 }
 
-static void hardware_disable(void *junk)
+static void hardware_enable(void *junk)
+{
+        spin_lock(&kvm_lock);
+        hardware_enable_nolock(junk);
+        spin_unlock(&kvm_lock);
+}
+
+static void hardware_disable_nolock(void *junk)
 {
         int cpu = raw_smp_processor_id();
 
@@ -2089,13 +2096,20 @@ static void hardware_disable(void *junk)
         kvm_arch_hardware_disable(NULL);
 }
 
+static void hardware_disable(void *junk)
+{
+        spin_lock(&kvm_lock);
+        hardware_disable_nolock(junk);
+        spin_unlock(&kvm_lock);
+}
+
 static void hardware_disable_all_nolock(void)
 {
         BUG_ON(!kvm_usage_count);
 
         kvm_usage_count--;
         if (!kvm_usage_count)
-                on_each_cpu(hardware_disable, NULL, 1);
+                on_each_cpu(hardware_disable_nolock, NULL, 1);
 }
 
 static void hardware_disable_all(void)
@@ -2114,7 +2128,7 @@ static int hardware_enable_all(void)
         kvm_usage_count++;
         if (kvm_usage_count == 1) {
                 atomic_set(&hardware_enable_failed, 0);
-                on_each_cpu(hardware_enable, NULL, 1);
+                on_each_cpu(hardware_enable_nolock, NULL, 1);
 
                 if (atomic_read(&hardware_enable_failed)) {
                         hardware_disable_all_nolock();
@@ -2140,16 +2154,12 @@ static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
         case CPU_DYING:
                 printk(KERN_INFO "kvm: disabling virtualization on CPU%d\n",
                        cpu);
-                spin_lock(&kvm_lock);
                 hardware_disable(NULL);
-                spin_unlock(&kvm_lock);
                 break;
         case CPU_STARTING:
                 printk(KERN_INFO "kvm: enabling virtualization on CPU%d\n",
                        cpu);
-                spin_lock(&kvm_lock);
                 hardware_enable(NULL);
-                spin_unlock(&kvm_lock);
                 break;
         }
         return NOTIFY_OK;
@@ -2180,7 +2190,7 @@ static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
          */
         printk(KERN_INFO "kvm: exiting hardware virtualization\n");
         kvm_rebooting = true;
-        on_each_cpu(hardware_disable, NULL, 1);
+        on_each_cpu(hardware_disable_nolock, NULL, 1);
         return NOTIFY_OK;
 }
 
@@ -2350,7 +2360,7 @@ static void kvm_exit_debug(void)
 static int kvm_suspend(struct sys_device *dev, pm_message_t state)
 {
         if (kvm_usage_count)
-                hardware_disable(NULL);
+                hardware_disable_nolock(NULL);
         return 0;
 }
 
@@ -2358,7 +2368,7 @@ static int kvm_resume(struct sys_device *dev)
 {
         if (kvm_usage_count) {
                 WARN_ON(spin_is_locked(&kvm_lock));
-                hardware_enable(NULL);
+                hardware_enable_nolock(NULL);
         }
         return 0;
 }
@@ -2535,7 +2545,7 @@ void kvm_exit(void)
         sysdev_class_unregister(&kvm_sysdev_class);
         unregister_reboot_notifier(&kvm_reboot_notifier);
         unregister_cpu_notifier(&kvm_cpu_notifier);
-        on_each_cpu(hardware_disable, NULL, 1);
+        on_each_cpu(hardware_disable_nolock, NULL, 1);
         kvm_arch_hardware_unsetup();
         kvm_arch_exit();
         free_cpumask_var(cpus_hardware_enabled);