Re: [RFC v2 06/11] vfio: Move device open/close code to be helpfers

From: Yi Liu <yi.l.liu@intel.com>
To: "Tian, Kevin" <kevin.tian@intel.com>,
	"alex.williamson@redhat.com" <alex.williamson@redhat.com>,
	"jgg@nvidia.com" <jgg@nvidia.com>
Cc: "eric.auger@redhat.com" <eric.auger@redhat.com>,
	"cohuck@redhat.com" <cohuck@redhat.com>,
	"nicolinc@nvidia.com" <nicolinc@nvidia.com>,
	"yi.y.sun@linux.intel.com" <yi.y.sun@linux.intel.com>,
	"chao.p.peng@linux.intel.com" <chao.p.peng@linux.intel.com>,
	"mjrosato@linux.ibm.com" <mjrosato@linux.ibm.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>
Subject: Re: [RFC v2 06/11] vfio: Move device open/close code to be helpfers
Date: Mon, 28 Nov 2022 17:27:45 +0800	[thread overview]
Message-ID: <f5fc63d2-f1ce-194f-b3ef-83d5ac5c0d02@intel.com> (raw)
In-Reply-To: <BN9PR11MB527600CC442882CD40563FAC8C139@BN9PR11MB5276.namprd11.prod.outlook.com>

On 2022/11/28 16:21, Tian, Kevin wrote:
>> From: Liu, Yi L <yi.l.liu@intel.com>
>> Sent: Thursday, November 24, 2022 8:27 PM
>>
>> This makes the device open and close be in paired helpers.
>>
>> vfio_device_open(), and vfio_device_close() handles the open_count, and
>> calls vfio_device_first_open(), and vfio_device_last_close() when
>> open_count condition is met. This also helps to avoid open code for device
>> in the vfio_group_ioctl_get_device_fd(), and prepares for further moving
> 
> I didn't get which 'open code' is referred to here:

it's the device->open_count things. but you are right, it's not in the
vfio_group_ioctl_get_device_fd().

>> @@ -918,7 +935,7 @@ static int vfio_group_ioctl_get_device_fd(struct
>> vfio_group *group,
>>   		goto err_put_device;
>>   	}
>>
>> -	filep = vfio_device_open(device);
>> +	filep = vfio_device_open_file(device);
> 
> it's simply a replacement of function calls.

so more accurate description is splitting the vfio_device_open() into
common vfio_device_open() which is paired with vfio_device_close(), and
another wrapper to deal with device open and device file open, which is
group path specific.

-- 
Regards,
Yi Liu