[RFC v2 6/6] KVM: eventfd: add irq bypass consumer management

From: Eric Auger
Date: Mon Jul 06 2015 - 08:12:38 EST


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

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>

---

v1 -> v2:
- populate of kvm and gsi removed
- unregister the consumer on irqfd_shutdown
---
include/linux/kvm_irqfd.h | 1 +
virt/kvm/eventfd.c | 14 +++++++++++---
2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/include/linux/kvm_irqfd.h b/include/linux/kvm_irqfd.h
index f926b39..3c0bd07 100644
--- a/include/linux/kvm_irqfd.h
+++ b/include/linux/kvm_irqfd.h
@@ -64,6 +64,7 @@ struct kvm_kernel_irqfd {
struct list_head list;
poll_table pt;
struct work_struct shutdown;
+ struct irq_bypass_consumer consumer;
};

#endif /* __LINUX_KVM_IRQFD_H */
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
index b79dc61..9452754 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 +141,7 @@ irqfd_shutdown(struct work_struct *work)
/*
* It is now safe to release the object's resources
*/
+ irq_bypass_unregister_consumer(&irqfd->consumer);
eventfd_ctx_put(irqfd->eventfd);
kfree(irqfd);
}
@@ -380,7 +382,14 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args)
*/
fdput(f);

- /* irq_bypass_register_consumer(); */
+ 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.resume = kvm_arch_irq_bypass_resume;
+ irqfd->consumer.update = kvm_arch_irq_bypass_update;
+ ret = irq_bypass_register_consumer(&irqfd->consumer);
+ WARN_ON(ret);

return 0;

@@ -481,8 +490,6 @@ kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd *args)
struct kvm_kernel_irqfd *irqfd, *tmp;
struct eventfd_ctx *eventfd;

- /* irq_bypass_unregister_consumer() */
-
eventfd = eventfd_ctx_fdget(args->fd);
if (IS_ERR(eventfd))
return PTR_ERR(eventfd);
@@ -501,6 +508,7 @@ kvm_irqfd_deassign(struct kvm *kvm, struct kvm_irqfd *args)
irqfd->irq_entry.type = 0;
write_seqcount_end(&irqfd->irq_entry_sc);
irqfd_deactivate(irqfd);
+ irq_bypass_unregister_consumer(&irqfd->consumer);
}
}

--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/