Received-SPF: pass (google.com: domain of linux-kernel+bounces-196110-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.199.223 as permitted sender) client-ip=147.75.199.223;
Message-ID: <cb8f4a3f-75f4-436a-96dc-301b6d65a55c@linux.intel.com>
Date: Fri, 31 May 2024 08:59:13 +0800
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Cc: baolu.lu@linux.intel.com, iommu@lists.linux.dev,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] iommu: Make iommu_sva_domain_alloc() static
To: Vasant Hegde <vasant.hegde@amd.com>, Joerg Roedel <joro@8bytes.org>,
 Will Deacon <will@kernel.org>, Robin Murphy <robin.murphy@arm.com>,
 Jason Gunthorpe <jgg@ziepe.ca>, Kevin Tian <kevin.tian@intel.com>,
 Jean-Philippe Brucker <jean-philippe@linaro.org>
References: <20240528045458.81458-1-baolu.lu@linux.intel.com>
 <fdc3bffa-7149-48a4-949a-dd469c6c2726@amd.com>
Content-Language: en-US
From: Baolu Lu <baolu.lu@linux.intel.com>
In-Reply-To: <fdc3bffa-7149-48a4-949a-dd469c6c2726@amd.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit

On 5/30/24 4:52 PM, Vasant Hegde wrote:
> On 5/28/2024 10:24 AM, Lu Baolu wrote:
>> iommu_sva_domain_alloc() is only called in iommu-sva.c, hence make it
>> static.
>>
>> On the other hand, iommu_sva_domain_alloc() should not return NULL anymore
>> after commit <80af5a452024> ("iommu: Add ops->domain_alloc_sva()"), the
>> removal of inline code avoids potential confusion.
>>
>> Fixes: 80af5a452024 ("iommu: Add ops->domain_alloc_sva()")
>> Signed-off-by: Lu Baolu<baolu.lu@linux.intel.com>
>> ---
>>   include/linux/iommu.h     | 8 --------
>>   drivers/iommu/iommu-sva.c | 6 ++++--
>>   2 files changed, 4 insertions(+), 10 deletions(-)
>>
>> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
>> index 7bc8dff7cf6d..5cdd3d41b87b 100644
>> --- a/include/linux/iommu.h
>> +++ b/include/linux/iommu.h
>> @@ -1527,8 +1527,6 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev,
>>   					struct mm_struct *mm);
>>   void iommu_sva_unbind_device(struct iommu_sva *handle);
>>   u32 iommu_sva_get_pasid(struct iommu_sva *handle);
>> -struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,
>> -					    struct mm_struct *mm);
>>   #else
>>   static inline struct iommu_sva *
>>   iommu_sva_bind_device(struct device *dev, struct mm_struct *mm)
>> @@ -1553,12 +1551,6 @@ static inline u32 mm_get_enqcmd_pasid(struct mm_struct *mm)
>>   }
>>   
>>   static inline void mm_pasid_drop(struct mm_struct *mm) {}
>> -
>> -static inline struct iommu_domain *
>> -iommu_sva_domain_alloc(struct device *dev, struct mm_struct *mm)
>> -{
>> -	return NULL;
>> -}
>>   #endif /* CONFIG_IOMMU_SVA */
>>   
>>   #ifdef CONFIG_IOMMU_IOPF
>> diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
>> index 18a35e798b72..25e581299226 100644
>> --- a/drivers/iommu/iommu-sva.c
>> +++ b/drivers/iommu/iommu-sva.c
>> @@ -10,6 +10,8 @@
>>   #include "iommu-priv.h"
>>   
>>   static DEFINE_MUTEX(iommu_sva_lock);
>> +static struct iommu_domain *iommu_sva_domain_alloc(struct device *dev,
>> +						   struct mm_struct *mm);
> If we move move iommu_sva_domain_alloc() before iommu_sva_bind_device() then we
> can avoid this forward declaration.

Yeah, but that means moving 144 lines of code. That's why I went with
this approach

Best regards,
baolu