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* [PATCH] iommu: Unify iova_to_phys for identity domains
@ 2021-07-14 17:28 ` Robin Murphy
  0 siblings, 0 replies; 8+ messages in thread
From: Robin Murphy @ 2021-07-14 17:28 UTC (permalink / raw)
  To: joro, will; +Cc: iommu, linux-arm-kernel

If people are going to insist on calling iommu_iova_to_phys()
pointlessly and expecting it to work, we can at least do ourselves a
favour by handling those cases in the core code, rather than repeatedly
across an inconsistent handful of drivers.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/iommu/amd/io_pgtable.c              | 3 ---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
 drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
 drivers/iommu/iommu.c                       | 6 +++++-
 4 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c
index bb0ee5c9fde7..182c93a43efd 100644
--- a/drivers/iommu/amd/io_pgtable.c
+++ b/drivers/iommu/amd/io_pgtable.c
@@ -493,9 +493,6 @@ static phys_addr_t iommu_v1_iova_to_phys(struct io_pgtable_ops *ops, unsigned lo
 	unsigned long offset_mask, pte_pgsize;
 	u64 *pte, __pte;
 
-	if (pgtable->mode == PAGE_MODE_NONE)
-		return iova;
-
 	pte = fetch_pte(pgtable, iova, &pte_pgsize);
 
 	if (!pte || !IOMMU_PTE_PRESENT(*pte))
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 3e87a9cf6da3..c9fdd0d097be 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2481,9 +2481,6 @@ arm_smmu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
 {
 	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
 
-	if (domain->type == IOMMU_DOMAIN_IDENTITY)
-		return iova;
-
 	if (!ops)
 		return 0;
 
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 0f181f76c31b..0d04eafa3fdb 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -1317,9 +1317,6 @@ static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
 
-	if (domain->type == IOMMU_DOMAIN_IDENTITY)
-		return iova;
-
 	if (!ops)
 		return 0;
 
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 43a2041d9629..7c16f977b5a6 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2371,7 +2371,11 @@ EXPORT_SYMBOL_GPL(iommu_detach_group);
 
 phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
 {
-	if (unlikely(domain->ops->iova_to_phys == NULL))
+	if (domain->type == IOMMU_DOMAIN_IDENTITY)
+		return iova;
+
+	if (unlikely(domain->ops->iova_to_phys == NULL) ||
+	    domain->type == IOMMU_DOMAIN_BLOCKED)
 		return 0;
 
 	return domain->ops->iova_to_phys(domain, iova);
-- 
2.25.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

^ permalink raw reply related	[flat|nested] 8+ messages in thread
* [PATCH] iommu: Unify iova_to_phys for identity domains
@ 2021-07-14 17:28 ` Robin Murphy
  0 siblings, 0 replies; 8+ messages in thread
From: Robin Murphy @ 2021-07-14 17:28 UTC (permalink / raw)
  To: joro, will; +Cc: iommu, linux-arm-kernel, sven

If people are going to insist on calling iommu_iova_to_phys()
pointlessly and expecting it to work, we can at least do ourselves a
favour by handling those cases in the core code, rather than repeatedly
across an inconsistent handful of drivers.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/iommu/amd/io_pgtable.c              | 3 ---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
 drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
 drivers/iommu/iommu.c                       | 6 +++++-
 4 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c
index bb0ee5c9fde7..182c93a43efd 100644
--- a/drivers/iommu/amd/io_pgtable.c
+++ b/drivers/iommu/amd/io_pgtable.c
@@ -493,9 +493,6 @@ static phys_addr_t iommu_v1_iova_to_phys(struct io_pgtable_ops *ops, unsigned lo
 	unsigned long offset_mask, pte_pgsize;
 	u64 *pte, __pte;
 
-	if (pgtable->mode == PAGE_MODE_NONE)
-		return iova;
-
 	pte = fetch_pte(pgtable, iova, &pte_pgsize);
 
 	if (!pte || !IOMMU_PTE_PRESENT(*pte))
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 3e87a9cf6da3..c9fdd0d097be 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2481,9 +2481,6 @@ arm_smmu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
 {
 	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
 
-	if (domain->type == IOMMU_DOMAIN_IDENTITY)
-		return iova;
-
 	if (!ops)
 		return 0;
 
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 0f181f76c31b..0d04eafa3fdb 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -1317,9 +1317,6 @@ static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
 	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
 	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
 
-	if (domain->type == IOMMU_DOMAIN_IDENTITY)
-		return iova;
-
 	if (!ops)
 		return 0;
 
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 43a2041d9629..7c16f977b5a6 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -2371,7 +2371,11 @@ EXPORT_SYMBOL_GPL(iommu_detach_group);
 
 phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
 {
-	if (unlikely(domain->ops->iova_to_phys == NULL))
+	if (domain->type == IOMMU_DOMAIN_IDENTITY)
+		return iova;
+
+	if (unlikely(domain->ops->iova_to_phys == NULL) ||
+	    domain->type == IOMMU_DOMAIN_BLOCKED)
 		return 0;
 
 	return domain->ops->iova_to_phys(domain, iova);
-- 
2.25.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply related	[flat|nested] 8+ messages in thread
* Re: [PATCH] iommu: Unify iova_to_phys for identity domains
  2021-07-14 17:28 ` Robin Murphy
@ 2021-07-15  1:38   ` Lu Baolu
  -1 siblings, 0 replies; 8+ messages in thread
From: Lu Baolu @ 2021-07-15  1:38 UTC (permalink / raw)
  To: Robin Murphy, joro, will; +Cc: iommu, linux-arm-kernel

On 7/15/21 1:28 AM, Robin Murphy wrote:
> If people are going to insist on calling iommu_iova_to_phys()
> pointlessly and expecting it to work, we can at least do ourselves a
> favour by handling those cases in the core code, rather than repeatedly
> across an inconsistent handful of drivers.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   drivers/iommu/amd/io_pgtable.c              | 3 ---
>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
>   drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
>   drivers/iommu/iommu.c                       | 6 +++++-
>   4 files changed, 5 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c
> index bb0ee5c9fde7..182c93a43efd 100644
> --- a/drivers/iommu/amd/io_pgtable.c
> +++ b/drivers/iommu/amd/io_pgtable.c
> @@ -493,9 +493,6 @@ static phys_addr_t iommu_v1_iova_to_phys(struct io_pgtable_ops *ops, unsigned lo
>   	unsigned long offset_mask, pte_pgsize;
>   	u64 *pte, __pte;
>   
> -	if (pgtable->mode == PAGE_MODE_NONE)
> -		return iova;
> -
>   	pte = fetch_pte(pgtable, iova, &pte_pgsize);
>   
>   	if (!pte || !IOMMU_PTE_PRESENT(*pte))
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index 3e87a9cf6da3..c9fdd0d097be 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -2481,9 +2481,6 @@ arm_smmu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
>   {
>   	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
>   
> -	if (domain->type == IOMMU_DOMAIN_IDENTITY)
> -		return iova;
> -
>   	if (!ops)
>   		return 0;
>   
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> index 0f181f76c31b..0d04eafa3fdb 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> @@ -1317,9 +1317,6 @@ static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
>   	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
>   	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
>   
> -	if (domain->type == IOMMU_DOMAIN_IDENTITY)
> -		return iova;
> -
>   	if (!ops)
>   		return 0;
>   
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 43a2041d9629..7c16f977b5a6 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -2371,7 +2371,11 @@ EXPORT_SYMBOL_GPL(iommu_detach_group);
>   
>   phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
>   {
> -	if (unlikely(domain->ops->iova_to_phys == NULL))
> +	if (domain->type == IOMMU_DOMAIN_IDENTITY)
> +		return iova;
> +
> +	if (unlikely(domain->ops->iova_to_phys == NULL) ||
> +	    domain->type == IOMMU_DOMAIN_BLOCKED)
>   		return 0;

Nit:
Logically we only needs ops->iova_to_phys for DMA and UNMANAGED domains,
so it looks better if we have

	if (domain->type == IOMMU_DOMAIN_BLOCKED ||
	    unlikely(domain->ops->iova_to_phys == NULL))
		return 0;

Anyway,

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>

Best regards,
baolu

>   
>   	return domain->ops->iova_to_phys(domain, iova);
> 
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] iommu: Unify iova_to_phys for identity domains
@ 2021-07-15  1:38   ` Lu Baolu
  0 siblings, 0 replies; 8+ messages in thread
From: Lu Baolu @ 2021-07-15  1:38 UTC (permalink / raw)
  To: Robin Murphy, joro, will; +Cc: baolu.lu, iommu, linux-arm-kernel

On 7/15/21 1:28 AM, Robin Murphy wrote:
> If people are going to insist on calling iommu_iova_to_phys()
> pointlessly and expecting it to work, we can at least do ourselves a
> favour by handling those cases in the core code, rather than repeatedly
> across an inconsistent handful of drivers.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>   drivers/iommu/amd/io_pgtable.c              | 3 ---
>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
>   drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
>   drivers/iommu/iommu.c                       | 6 +++++-
>   4 files changed, 5 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c
> index bb0ee5c9fde7..182c93a43efd 100644
> --- a/drivers/iommu/amd/io_pgtable.c
> +++ b/drivers/iommu/amd/io_pgtable.c
> @@ -493,9 +493,6 @@ static phys_addr_t iommu_v1_iova_to_phys(struct io_pgtable_ops *ops, unsigned lo
>   	unsigned long offset_mask, pte_pgsize;
>   	u64 *pte, __pte;
>   
> -	if (pgtable->mode == PAGE_MODE_NONE)
> -		return iova;
> -
>   	pte = fetch_pte(pgtable, iova, &pte_pgsize);
>   
>   	if (!pte || !IOMMU_PTE_PRESENT(*pte))
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index 3e87a9cf6da3..c9fdd0d097be 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -2481,9 +2481,6 @@ arm_smmu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
>   {
>   	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
>   
> -	if (domain->type == IOMMU_DOMAIN_IDENTITY)
> -		return iova;
> -
>   	if (!ops)
>   		return 0;
>   
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> index 0f181f76c31b..0d04eafa3fdb 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> @@ -1317,9 +1317,6 @@ static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
>   	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
>   	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
>   
> -	if (domain->type == IOMMU_DOMAIN_IDENTITY)
> -		return iova;
> -
>   	if (!ops)
>   		return 0;
>   
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index 43a2041d9629..7c16f977b5a6 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -2371,7 +2371,11 @@ EXPORT_SYMBOL_GPL(iommu_detach_group);
>   
>   phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
>   {
> -	if (unlikely(domain->ops->iova_to_phys == NULL))
> +	if (domain->type == IOMMU_DOMAIN_IDENTITY)
> +		return iova;
> +
> +	if (unlikely(domain->ops->iova_to_phys == NULL) ||
> +	    domain->type == IOMMU_DOMAIN_BLOCKED)
>   		return 0;

Nit:
Logically we only needs ops->iova_to_phys for DMA and UNMANAGED domains,
so it looks better if we have

	if (domain->type == IOMMU_DOMAIN_BLOCKED ||
	    unlikely(domain->ops->iova_to_phys == NULL))
		return 0;

Anyway,

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>

Best regards,
baolu

>   
>   	return domain->ops->iova_to_phys(domain, iova);
> 

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] iommu: Unify iova_to_phys for identity domains
  2021-07-15  1:38   ` Lu Baolu
@ 2021-07-15  8:53     ` Robin Murphy
  -1 siblings, 0 replies; 8+ messages in thread
From: Robin Murphy @ 2021-07-15  8:53 UTC (permalink / raw)
  To: Lu Baolu, joro, will; +Cc: iommu, linux-arm-kernel

On 2021-07-15 02:38, Lu Baolu wrote:
> On 7/15/21 1:28 AM, Robin Murphy wrote:
>> If people are going to insist on calling iommu_iova_to_phys()
>> pointlessly and expecting it to work, we can at least do ourselves a
>> favour by handling those cases in the core code, rather than repeatedly
>> across an inconsistent handful of drivers.
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>>   drivers/iommu/amd/io_pgtable.c              | 3 ---
>>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
>>   drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
>>   drivers/iommu/iommu.c                       | 6 +++++-
>>   4 files changed, 5 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/iommu/amd/io_pgtable.c 
>> b/drivers/iommu/amd/io_pgtable.c
>> index bb0ee5c9fde7..182c93a43efd 100644
>> --- a/drivers/iommu/amd/io_pgtable.c
>> +++ b/drivers/iommu/amd/io_pgtable.c
>> @@ -493,9 +493,6 @@ static phys_addr_t iommu_v1_iova_to_phys(struct 
>> io_pgtable_ops *ops, unsigned lo
>>       unsigned long offset_mask, pte_pgsize;
>>       u64 *pte, __pte;
>> -    if (pgtable->mode == PAGE_MODE_NONE)
>> -        return iova;
>> -
>>       pte = fetch_pte(pgtable, iova, &pte_pgsize);
>>       if (!pte || !IOMMU_PTE_PRESENT(*pte))
>> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c 
>> b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> index 3e87a9cf6da3..c9fdd0d097be 100644
>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> @@ -2481,9 +2481,6 @@ arm_smmu_iova_to_phys(struct iommu_domain 
>> *domain, dma_addr_t iova)
>>   {
>>       struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
>> -    if (domain->type == IOMMU_DOMAIN_IDENTITY)
>> -        return iova;
>> -
>>       if (!ops)
>>           return 0;
>> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c 
>> b/drivers/iommu/arm/arm-smmu/arm-smmu.c
>> index 0f181f76c31b..0d04eafa3fdb 100644
>> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
>> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
>> @@ -1317,9 +1317,6 @@ static phys_addr_t arm_smmu_iova_to_phys(struct 
>> iommu_domain *domain,
>>       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
>>       struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
>> -    if (domain->type == IOMMU_DOMAIN_IDENTITY)
>> -        return iova;
>> -
>>       if (!ops)
>>           return 0;
>> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
>> index 43a2041d9629..7c16f977b5a6 100644
>> --- a/drivers/iommu/iommu.c
>> +++ b/drivers/iommu/iommu.c
>> @@ -2371,7 +2371,11 @@ EXPORT_SYMBOL_GPL(iommu_detach_group);
>>   phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, 
>> dma_addr_t iova)
>>   {
>> -    if (unlikely(domain->ops->iova_to_phys == NULL))
>> +    if (domain->type == IOMMU_DOMAIN_IDENTITY)
>> +        return iova;
>> +
>> +    if (unlikely(domain->ops->iova_to_phys == NULL) ||
>> +        domain->type == IOMMU_DOMAIN_BLOCKED)
>>           return 0;
> 
> Nit:
> Logically we only needs ops->iova_to_phys for DMA and UNMANAGED domains,
> so it looks better if we have
> 
>      if (domain->type == IOMMU_DOMAIN_BLOCKED ||
>          unlikely(domain->ops->iova_to_phys == NULL))
>          return 0;

Yeah, I put IOMMU_DOMAIN_BLOCKED last as the least likely condition 
since it's really just for completeness - I don't think it's possible to 
see it legitimately used at the moment - but on second look I think 
ops->iova_to_phys == NULL is equally theoretical now, so maybe I could 
be removing that and we just make it mandatory for any new drivers?

> Anyway,
> 
> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>

Thanks!

Robin.

> 
> Best regards,
> baolu
> 
>>       return domain->ops->iova_to_phys(domain, iova);
>>
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] iommu: Unify iova_to_phys for identity domains
@ 2021-07-15  8:53     ` Robin Murphy
  0 siblings, 0 replies; 8+ messages in thread
From: Robin Murphy @ 2021-07-15  8:53 UTC (permalink / raw)
  To: Lu Baolu, joro, will; +Cc: iommu, linux-arm-kernel

On 2021-07-15 02:38, Lu Baolu wrote:
> On 7/15/21 1:28 AM, Robin Murphy wrote:
>> If people are going to insist on calling iommu_iova_to_phys()
>> pointlessly and expecting it to work, we can at least do ourselves a
>> favour by handling those cases in the core code, rather than repeatedly
>> across an inconsistent handful of drivers.
>>
>> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
>> ---
>>   drivers/iommu/amd/io_pgtable.c              | 3 ---
>>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
>>   drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
>>   drivers/iommu/iommu.c                       | 6 +++++-
>>   4 files changed, 5 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/iommu/amd/io_pgtable.c 
>> b/drivers/iommu/amd/io_pgtable.c
>> index bb0ee5c9fde7..182c93a43efd 100644
>> --- a/drivers/iommu/amd/io_pgtable.c
>> +++ b/drivers/iommu/amd/io_pgtable.c
>> @@ -493,9 +493,6 @@ static phys_addr_t iommu_v1_iova_to_phys(struct 
>> io_pgtable_ops *ops, unsigned lo
>>       unsigned long offset_mask, pte_pgsize;
>>       u64 *pte, __pte;
>> -    if (pgtable->mode == PAGE_MODE_NONE)
>> -        return iova;
>> -
>>       pte = fetch_pte(pgtable, iova, &pte_pgsize);
>>       if (!pte || !IOMMU_PTE_PRESENT(*pte))
>> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c 
>> b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> index 3e87a9cf6da3..c9fdd0d097be 100644
>> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
>> @@ -2481,9 +2481,6 @@ arm_smmu_iova_to_phys(struct iommu_domain 
>> *domain, dma_addr_t iova)
>>   {
>>       struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
>> -    if (domain->type == IOMMU_DOMAIN_IDENTITY)
>> -        return iova;
>> -
>>       if (!ops)
>>           return 0;
>> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c 
>> b/drivers/iommu/arm/arm-smmu/arm-smmu.c
>> index 0f181f76c31b..0d04eafa3fdb 100644
>> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
>> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
>> @@ -1317,9 +1317,6 @@ static phys_addr_t arm_smmu_iova_to_phys(struct 
>> iommu_domain *domain,
>>       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
>>       struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
>> -    if (domain->type == IOMMU_DOMAIN_IDENTITY)
>> -        return iova;
>> -
>>       if (!ops)
>>           return 0;
>> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
>> index 43a2041d9629..7c16f977b5a6 100644
>> --- a/drivers/iommu/iommu.c
>> +++ b/drivers/iommu/iommu.c
>> @@ -2371,7 +2371,11 @@ EXPORT_SYMBOL_GPL(iommu_detach_group);
>>   phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, 
>> dma_addr_t iova)
>>   {
>> -    if (unlikely(domain->ops->iova_to_phys == NULL))
>> +    if (domain->type == IOMMU_DOMAIN_IDENTITY)
>> +        return iova;
>> +
>> +    if (unlikely(domain->ops->iova_to_phys == NULL) ||
>> +        domain->type == IOMMU_DOMAIN_BLOCKED)
>>           return 0;
> 
> Nit:
> Logically we only needs ops->iova_to_phys for DMA and UNMANAGED domains,
> so it looks better if we have
> 
>      if (domain->type == IOMMU_DOMAIN_BLOCKED ||
>          unlikely(domain->ops->iova_to_phys == NULL))
>          return 0;

Yeah, I put IOMMU_DOMAIN_BLOCKED last as the least likely condition 
since it's really just for completeness - I don't think it's possible to 
see it legitimately used at the moment - but on second look I think 
ops->iova_to_phys == NULL is equally theoretical now, so maybe I could 
be removing that and we just make it mandatory for any new drivers?

> Anyway,
> 
> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>

Thanks!

Robin.

> 
> Best regards,
> baolu
> 
>>       return domain->ops->iova_to_phys(domain, iova);
>>

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^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] iommu: Unify iova_to_phys for identity domains
  2021-07-14 17:28 ` Robin Murphy
@ 2021-07-26 11:34   ` Joerg Roedel
  -1 siblings, 0 replies; 8+ messages in thread
From: Joerg Roedel @ 2021-07-26 11:34 UTC (permalink / raw)
  To: Robin Murphy; +Cc: iommu, will, linux-arm-kernel

On Wed, Jul 14, 2021 at 06:28:34PM +0100, Robin Murphy wrote:
> If people are going to insist on calling iommu_iova_to_phys()
> pointlessly and expecting it to work, we can at least do ourselves a
> favour by handling those cases in the core code, rather than repeatedly
> across an inconsistent handful of drivers.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>  drivers/iommu/amd/io_pgtable.c              | 3 ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
>  drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
>  drivers/iommu/iommu.c                       | 6 +++++-
>  4 files changed, 5 insertions(+), 10 deletions(-)

Applied to iommu/core, thanks.

_______________________________________________
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iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

^ permalink raw reply	[flat|nested] 8+ messages in thread
* Re: [PATCH] iommu: Unify iova_to_phys for identity domains
@ 2021-07-26 11:34   ` Joerg Roedel
  0 siblings, 0 replies; 8+ messages in thread
From: Joerg Roedel @ 2021-07-26 11:34 UTC (permalink / raw)
  To: Robin Murphy; +Cc: will, iommu, linux-arm-kernel, sven

On Wed, Jul 14, 2021 at 06:28:34PM +0100, Robin Murphy wrote:
> If people are going to insist on calling iommu_iova_to_phys()
> pointlessly and expecting it to work, we can at least do ourselves a
> favour by handling those cases in the core code, rather than repeatedly
> across an inconsistent handful of drivers.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>  drivers/iommu/amd/io_pgtable.c              | 3 ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 ---
>  drivers/iommu/arm/arm-smmu/arm-smmu.c       | 3 ---
>  drivers/iommu/iommu.c                       | 6 +++++-
>  4 files changed, 5 insertions(+), 10 deletions(-)

Applied to iommu/core, thanks.


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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply	[flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-07-26 11:36 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-07-14 17:28 [PATCH] iommu: Unify iova_to_phys for identity domains Robin Murphy
2021-07-14 17:28 ` Robin Murphy
2021-07-15  1:38 ` Lu Baolu
2021-07-15  1:38   ` Lu Baolu
2021-07-15  8:53   ` Robin Murphy
2021-07-15  8:53     ` Robin Murphy
2021-07-26 11:34 ` Joerg Roedel
2021-07-26 11:34   ` Joerg Roedel

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