Re: [BUG] dma-ranges, reserved memory regions, dma_alloc_coherent: possible bug?

[Alexandre Torgue <alexandre.torgue@st.com>]

Hi Vlad,

On 10/24/19 2:43 PM, Vladimir Murzin wrote:
> On 10/17/19 10:46 AM, Vladimir Murzin wrote:
>> I'm wondering if I've missed something with diff bellow (it was a long time ago when I touched DMA)?
> 
> Any comments on that? I can only build test it, so lack of testing stopping me from sending it as a
> proper patch :(

I can make some tests tomorrow. Which particular setup I need to test: 
cortex M7 + cache + dma + xip ? Let me know.

regards
alex

> 
>>
>> diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c
>> index db92478..287ef89 100644
>> --- a/arch/arm/mm/dma-mapping-nommu.c
>> +++ b/arch/arm/mm/dma-mapping-nommu.c
>> @@ -35,7 +35,7 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size,
>>   				 unsigned long attrs)
>>   
>>   {
>> -	void *ret = dma_alloc_from_global_coherent(size, dma_handle);
>> +	void *ret = dma_alloc_from_global_coherent(dev, size, dma_handle);
>>   
>>   	/*
>>   	 * dma_alloc_from_global_coherent() may fail because:
>> diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
>> index 4a1c4fc..10918c5 100644
>> --- a/include/linux/dma-mapping.h
>> +++ b/include/linux/dma-mapping.h
>> @@ -162,7 +162,7 @@ int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr);
>>   int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma,
>>   			    void *cpu_addr, size_t size, int *ret);
>>   
>> -void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle);
>> +void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size, dma_addr_t *dma_handle);
>>   int dma_release_from_global_coherent(int order, void *vaddr);
>>   int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr,
>>   				  size_t size, int *ret);
>> @@ -172,7 +172,7 @@ int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr,
>>   #define dma_release_from_dev_coherent(dev, order, vaddr) (0)
>>   #define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0)
>>   
>> -static inline void *dma_alloc_from_global_coherent(ssize_t size,
>> +static inline void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size,
>>   						   dma_addr_t *dma_handle)
>>   {
>>   	return NULL;
>> diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
>> index 545e386..551b0eb 100644
>> --- a/kernel/dma/coherent.c
>> +++ b/kernel/dma/coherent.c
>> @@ -123,8 +123,9 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
>>   	return ret;
>>   }
>>   
>> -static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem,
>> -		ssize_t size, dma_addr_t *dma_handle)
>> +static void *__dma_alloc_from_coherent(struct device *dev,
>> +				       struct dma_coherent_mem *mem,
>> +				       ssize_t size, dma_addr_t *dma_handle)
>>   {
>>   	int order = get_order(size);
>>   	unsigned long flags;
>> @@ -143,7 +144,7 @@ static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem,
>>   	/*
>>   	 * Memory was found in the coherent area.
>>   	 */
>> -	*dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
>> +	*dma_handle = dma_get_device_base(dev, mem) + (pageno << PAGE_SHIFT);
>>   	ret = mem->virt_base + (pageno << PAGE_SHIFT);
>>   	spin_unlock_irqrestore(&mem->spinlock, flags);
>>   	memset(ret, 0, size);
>> @@ -175,17 +176,18 @@ int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
>>   	if (!mem)
>>   		return 0;
>>   
>> -	*ret = __dma_alloc_from_coherent(mem, size, dma_handle);
>> +	*ret = __dma_alloc_from_coherent(dev, mem, size, dma_handle);
>>   	return 1;
>>   }
>>   
>> -void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle)
>> +void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size,
>> +				     dma_addr_t *dma_handle)
>>   {
>>   	if (!dma_coherent_default_memory)
>>   		return NULL;
>>   
>> -	return __dma_alloc_from_coherent(dma_coherent_default_memory, size,
>> -			dma_handle);
>> +	return __dma_alloc_from_coherent(dev, dma_coherent_default_memory, size,
>> +					 dma_handle);
>>   }
>>   
>>   static int __dma_release_from_coherent(struct dma_coherent_mem *mem,
> 
> 
> Thanks
> Vladimir
> 
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu