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Date:   Fri, 19 Jul 2019 10:25:16 -0600
From:   Alex Williamson <alex.williamson@redhat.com>
To:     Kechen Lu <kechen.lu@intel.com>
Cc:     intel-gvt-dev@lists.freedesktop.org, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, Tina Zhang <tina.zhang@intel.com>,
        kraxel@redhat.com, zhenyuw@linux.intel.com, zhiyuan.lv@intel.com,
        zhi.a.wang@intel.com, kevin.tian@intel.com, hang.yuan@intel.com
Subject: Re: [RFC PATCH v4 2/6] vfio: Introduce vGPU display irq type
Message-ID: <20190719102516.60af527f@x1.home>
In-Reply-To: <20190718155640.25928-3-kechen.lu@intel.com>
References: <20190718155640.25928-1-kechen.lu@intel.com>
        <20190718155640.25928-3-kechen.lu@intel.com>
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On Thu, 18 Jul 2019 23:56:36 +0800
Kechen Lu <kechen.lu@intel.com> wrote:

> From: Tina Zhang <tina.zhang@intel.com>
> 
> Introduce vGPU specific irq type VFIO_IRQ_TYPE_GFX, and
> VFIO_IRQ_SUBTYPE_GFX_DISPLAY_IRQ as the subtype for vGPU display
> 
> Signed-off-by: Tina Zhang <tina.zhang@intel.com>
> ---
>  include/uapi/linux/vfio.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> index be6adab4f759..df28b17a6e2e 100644
> --- a/include/uapi/linux/vfio.h
> +++ b/include/uapi/linux/vfio.h
> @@ -469,6 +469,9 @@ struct vfio_irq_info_cap_type {
>  	__u32 subtype;  /* type specific */
>  };
>  
> +#define VFIO_IRQ_TYPE_GFX				(1)
> +#define VFIO_IRQ_SUBTYPE_GFX_DISPLAY_IRQ		(1)
> +

Please include a description defining exactly what this IRQ is intended
to signal.  For instance, if another vGPU vendor wanted to implement
this in their driver and didn't have the QEMU code for reference to
what it does with the IRQ, what would they need to know?  Thanks,

Alex 

>  /**
>   * VFIO_DEVICE_SET_IRQS - _IOW(VFIO_TYPE, VFIO_BASE + 10, struct vfio_irq_set)
>   *