KVM: eventfd: add irq bypass consumer management

This patch adds the registration/unregistration of an
irq_bypass_consumer on irqfd assignment/deassignment.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Feng Wu <feng.wu@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index c4f7abec4261..7df356d8f1fd 100644
--- a/virt/kvm/eventfd.c
+++ b/virt/kvm/eventfd.c
@@ -35,6 +35,7 @@
 #include <linux/srcu.h>
 #include <linux/slab.h>
 #include <linux/seqlock.h>
+#include <linux/irqbypass.h>
 #include <trace/events/kvm.h>
 
 #include <kvm/iodev.h>
@@ -140,6 +141,9 @@ irqfd_shutdown(struct work_struct *work)
         /*
          * It is now safe to release the object's resources
          */
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
+        irq_bypass_unregister_consumer(&irqfd->consumer);
+#endif
         eventfd_ctx_put(irqfd->eventfd);
         kfree(irqfd);
 }
@@ -391,6 +395,17 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
          * we might race against the POLLHUP
          */
         fdput(f);
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
+        irqfd->consumer.token = (void *)irqfd->eventfd;
+        irqfd->consumer.add_producer = kvm_arch_irq_bypass_add_producer;
+        irqfd->consumer.del_producer = kvm_arch_irq_bypass_del_producer;
+        irqfd->consumer.stop = kvm_arch_irq_bypass_stop;
+        irqfd->consumer.start = kvm_arch_irq_bypass_start;
+        ret = irq_bypass_register_consumer(&irqfd->consumer);
+        if (ret)
+                pr_info("irq bypass consumer (token %p) registration fails: %d\n",
+                                irqfd->consumer.token, ret);
+#endif
 
         return 0;