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Subject: Re: [PATCH v3 1/5] vfio/migration: Add debugfs to live migration
 driver
To:     Jason Gunthorpe <jgg@nvidia.com>
CC:     <alex.williamson@redhat.com>,
        <shameerali.kolothum.thodi@huawei.com>, <john.garry@huawei.com>,
        <cohuck@redhat.com>, <linux-kernel@vger.kernel.org>,
        <linuxarm@openeuler.org>
References: <20221128031200.11017-1-liulongfang@huawei.com>
 <20221128031200.11017-2-liulongfang@huawei.com> <Y4S59c2dWqdrdUlg@nvidia.com>
From:   liulongfang <liulongfang@huawei.com>
Message-ID: <ca3059d7-c73c-e712-9924-94891229cefd@huawei.com>
Date:   Tue, 29 Nov 2022 10:02:46 +0800
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On 2022/11/28 21:39, Jason Gunthorpe wrote:
> On Mon, Nov 28, 2022 at 11:11:56AM +0800, Longfang Liu wrote:
> 
>> @@ -119,6 +132,9 @@ struct vfio_migration_ops {
>>  				   enum vfio_device_mig_state *curr_state);
>>  	int (*migration_get_data_size)(struct vfio_device *device,
>>  				       unsigned long *stop_copy_length);
>> +	int (*migration_get_data)(struct vfio_device *device, char *buffer);
>> +	int (*migration_get_attr)(struct vfio_device *device, char *buffer);
>> +	int (*migration_debug_operate)(struct vfio_device *device,
>>  				   unsigned int cmd);
> 
> Please don't do wrappers like this, give the variant driver a chance
> to create its own files natively under the debugfs directory
> 

Using this public debugfs file does not need to deal with file
creation and destruction.
The driver only needs to define its debug operation command,
isn't it simpler?

Thanks,
Longfang.
> Jason
> .
>