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Subject: Re: [RFC 04/20] iommu: Add iommu_device_get_info interface
To:     Jason Gunthorpe <jgg@nvidia.com>, Liu Yi L <yi.l.liu@intel.com>
References: <20210919063848.1476776-1-yi.l.liu@intel.com>
 <20210919063848.1476776-5-yi.l.liu@intel.com>
 <20210921161930.GP327412@nvidia.com>
From:   Lu Baolu <baolu.lu@linux.intel.com>
Message-ID: <a8a72eba-bae3-9f42-f79c-c5646e425255@linux.intel.com>
Date:   Wed, 22 Sep 2021 10:31:47 +0800
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Hi Jason,

On 9/22/21 12:19 AM, Jason Gunthorpe wrote:
> On Sun, Sep 19, 2021 at 02:38:32PM +0800, Liu Yi L wrote:
>> From: Lu Baolu <baolu.lu@linux.intel.com>
>>
>> This provides an interface for upper layers to get the per-device iommu
>> attributes.
>>
>>      int iommu_device_get_info(struct device *dev,
>>                                enum iommu_devattr attr, void *data);
> 
> Can't we use properly typed ops and functions here instead of a void
> *data?
> 
> get_snoop()
> get_page_size()
> get_addr_width()

Yeah! Above are more friendly to the upper layer callers.

> 
> ?
> 
> Jason
> 

Best regards,
baolu