KVM: Initialize irqfd from kvm_init().

Currently, eventfd introduces module_init/module_exit functions
to initialize/cleanup the irqfd workqueue. This only works, however,
if no other module_init/module_exit functions are built into the
same module.

Let's just move the initialization and cleanup to kvm_init and kvm_exit.
This way, it is also clearer where kvm startup may fail.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

3 files changed, 21 insertions, 5 deletions

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index ac584cc53581..d50fe173028b 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -424,6 +424,19 @@ void kvm_vcpu_uninit(struct kvm_vcpu *vcpu);
 int __must_check vcpu_load(struct kvm_vcpu *vcpu);
 void vcpu_put(struct kvm_vcpu *vcpu);
 
+#ifdef __KVM_HAVE_IOAPIC
+int kvm_irqfd_init(void);
+void kvm_irqfd_exit(void);
+#else
+static inline int kvm_irqfd_init(void)
+{
+        return 0;
+}
+
+static inline void kvm_irqfd_exit(void)
+{
+}
+#endif
 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
                   struct module *module);
 void kvm_exit(void);
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index adb17f266b28..0b6fe69bb03d 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -543,7 +543,7 @@ void kvm_irq_routing_update(struct kvm *kvm,
  * aggregated from all vm* instances. We need our own isolated single-thread
  * queue to prevent deadlock against flushing the normal work-queue.
  */
-static int __init irqfd_module_init(void)
+int kvm_irqfd_init(void)
 {
         irqfd_cleanup_wq = create_singlethread_workqueue("kvm-irqfd-cleanup");
         if (!irqfd_cleanup_wq)
@@ -552,13 +552,10 @@ static int __init irqfd_module_init(void)
         return 0;
 }
 
-static void __exit irqfd_module_exit(void)
+void kvm_irqfd_exit(void)
 {
         destroy_workqueue(irqfd_cleanup_wq);
 }
-
-module_init(irqfd_module_init);
-module_exit(irqfd_module_exit);
 #endif
 
 /*
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0e919a1d4d56..faf05bddd131 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2898,6 +2898,9 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
         int r;
         int cpu;
 
+        r = kvm_irqfd_init();
+        if (r)
+                goto out_irqfd;
         r = kvm_arch_init(opaque);
         if (r)
                 goto out_fail;
@@ -2978,6 +2981,8 @@ out_free_0a:
 out_free_0:
         kvm_arch_exit();
 out_fail:
+        kvm_irqfd_exit();
+out_irqfd:
         return r;
 }
 EXPORT_SYMBOL_GPL(kvm_init);
@@ -2994,6 +2999,7 @@ void kvm_exit(void)
         on_each_cpu(hardware_disable_nolock, NULL, 1);
         kvm_arch_hardware_unsetup();
         kvm_arch_exit();
+        kvm_irqfd_exit();
         free_cpumask_var(cpus_hardware_enabled);
 }
 EXPORT_SYMBOL_GPL(kvm_exit);