From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alex Williamson <alex.williamson@redhat.com>
Subject: Re: [v5 09/19] vfio: Register/unregister irq_bypass_producer
Date: Mon, 13 Jul 2015 12:57:29 -0600
Message-ID: <1436813849.1391.380.camel@redhat.com>
References: <1436780855-3617-1-git-send-email-feng.wu@intel.com>
	 <1436780855-3617-10-git-send-email-feng.wu@intel.com>
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Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	pbonzini@redhat.com, joro@8bytes.org, eric.auger@linaro.org
To: Feng Wu <feng.wu@intel.com>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <1436780855-3617-10-git-send-email-feng.wu@intel.com>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

On Mon, 2015-07-13 at 17:47 +0800, Feng Wu wrote:
> This patch adds the registration/unregistration of an
> irq_bypass_producer for MSI/MSIx on vfio pci devices.
> 
> Signed-off-by: Feng Wu <feng.wu@intel.com>
> ---
>  drivers/vfio/pci/vfio_pci_intrs.c   | 19 +++++++++++++++++++
>  drivers/vfio/pci/vfio_pci_private.h |  2 ++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
> index 1f577b4..4795606 100644
> --- a/drivers/vfio/pci/vfio_pci_intrs.c
> +++ b/drivers/vfio/pci/vfio_pci_intrs.c
> @@ -305,6 +305,16 @@ static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix)
>  	return 0;
>  }
>  
> +void vfio_pci_add_consumer(struct irq_bypass_producer *prod,
> +			     struct irq_bypass_consumer *cons)
> +{
> +}
> +
> +void vfio_pci_del_consumer(struct irq_bypass_producer *prod,
> +			     struct irq_bypass_consumer *cons)
> +{
> +}
> +

Yes, as Eric says, these should be static

>  static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
>  				      int vector, int fd, bool msix)
>  {
> @@ -319,6 +329,7 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
>  
>  	if (vdev->ctx[vector].trigger) {
>  		free_irq(irq, vdev->ctx[vector].trigger);
> +		irq_bypass_unregister_producer(&vdev->ctx[vector].producer);
>  		kfree(vdev->ctx[vector].name);
>  		eventfd_ctx_put(vdev->ctx[vector].trigger);
>  		vdev->ctx[vector].trigger = NULL;
> @@ -360,6 +371,14 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
>  		return ret;
>  	}
>  
> +	INIT_LIST_HEAD(&vdev->ctx[vector].producer.node);

nit, INIT_LIST_HEAD isn't really needed, irq-bypass-manager shouldn't
trust incoming data here anyway.

> +	vdev->ctx[vector].producer.token = trigger;
> +	vdev->ctx[vector].producer.irq = irq;
> +	vdev->ctx[vector].producer.add_consumer = vfio_pci_add_consumer;
> +	vdev->ctx[vector].producer.del_consumer = vfio_pci_del_consumer;
> +	ret = irq_bypass_register_producer(&vdev->ctx[vector].producer);
> +	WARN_ON(ret);

This is only an acceleration path, so a dev_dbg() or dev_info() is
probably more appropriate.  Same for kvm side.

> +
>  	vdev->ctx[vector].trigger = trigger;
>  
>  	return 0;
> diff --git a/drivers/vfio/pci/vfio_pci_private.h b/drivers/vfio/pci/vfio_pci_private.h
> index ae0e1b4..0e7394f 100644
> --- a/drivers/vfio/pci/vfio_pci_private.h
> +++ b/drivers/vfio/pci/vfio_pci_private.h
> @@ -13,6 +13,7 @@
>  
>  #include <linux/mutex.h>
>  #include <linux/pci.h>
> +#include <linux/irqbypass.h>
>  
>  #ifndef VFIO_PCI_PRIVATE_H
>  #define VFIO_PCI_PRIVATE_H
> @@ -29,6 +30,7 @@ struct vfio_pci_irq_ctx {
>  	struct virqfd		*mask;
>  	char			*name;
>  	bool			masked;
> +	struct irq_bypass_producer	producer;
>  };
>  
>  struct vfio_pci_device {