[Intel-gfx] [PATCH v2 13/15] drm/ttm: Add BO and offset arguments for vm_access and vm_fault ttm handlers.

Christian König christian.koenig at amd.com
Tue May 18 11:59:25 UTC 2021


Can you send me the patch directly and not just on CC?

Thanks,
Christian.

Am 18.05.21 um 10:59 schrieb Thomas Hellström:
> + Christian König
>
> On 5/18/21 10:26 AM, Thomas Hellström wrote:
>> From: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>>
>> This allows other drivers that may not setup the vma in the same way
>> to use the ttm bo helpers.
>>
>> Also clarify the documentation a bit, especially related to 
>> VM_FAULT_RETRY.
>>
>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>
> Lgtm. Reviewed-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c    |  4 +-
>>   drivers/gpu/drm/nouveau/nouveau_ttm.c      |  4 +-
>>   drivers/gpu/drm/radeon/radeon_ttm.c        |  4 +-
>>   drivers/gpu/drm/ttm/ttm_bo_vm.c            | 84 +++++++++++++---------
>>   drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c |  8 ++-
>>   include/drm/ttm/ttm_bo_api.h               |  9 ++-
>>   6 files changed, 75 insertions(+), 38 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> index d5a9d7a88315..89dafe14f828 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> @@ -1919,7 +1919,9 @@ static vm_fault_t amdgpu_ttm_fault(struct 
>> vm_fault *vmf)
>>       if (ret)
>>           goto unlock;
>>   -    ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot,
>> +    ret = ttm_bo_vm_fault_reserved(bo, vmf,
>> + drm_vma_node_start(&bo->base.vma_node),
>> +                       vmf->vma->vm_page_prot,
>>                          TTM_BO_VM_NUM_PREFAULT, 1);
>>       if (ret == VM_FAULT_RETRY && !(vmf->flags & 
>> FAULT_FLAG_RETRY_NOWAIT))
>>           return ret;
>> diff --git a/drivers/gpu/drm/nouveau/nouveau_ttm.c 
>> b/drivers/gpu/drm/nouveau/nouveau_ttm.c
>> index b81ae90b8449..555fb6d8be8b 100644
>> --- a/drivers/gpu/drm/nouveau/nouveau_ttm.c
>> +++ b/drivers/gpu/drm/nouveau/nouveau_ttm.c
>> @@ -144,7 +144,9 @@ static vm_fault_t nouveau_ttm_fault(struct 
>> vm_fault *vmf)
>>         nouveau_bo_del_io_reserve_lru(bo);
>>       prot = vm_get_page_prot(vma->vm_flags);
>> -    ret = ttm_bo_vm_fault_reserved(vmf, prot, 
>> TTM_BO_VM_NUM_PREFAULT, 1);
>> +    ret = ttm_bo_vm_fault_reserved(bo, vmf,
>> + drm_vma_node_start(&bo->base.vma_node),
>> +                       prot, TTM_BO_VM_NUM_PREFAULT, 1);
>>       nouveau_bo_add_io_reserve_lru(bo);
>>       if (ret == VM_FAULT_RETRY && !(vmf->flags & 
>> FAULT_FLAG_RETRY_NOWAIT))
>>           return ret;
>> diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c 
>> b/drivers/gpu/drm/radeon/radeon_ttm.c
>> index 3361d11769a2..ba48a2acdef0 100644
>> --- a/drivers/gpu/drm/radeon/radeon_ttm.c
>> +++ b/drivers/gpu/drm/radeon/radeon_ttm.c
>> @@ -816,7 +816,9 @@ static vm_fault_t radeon_ttm_fault(struct 
>> vm_fault *vmf)
>>       if (ret)
>>           goto unlock_resv;
>>   -    ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot,
>> +    ret = ttm_bo_vm_fault_reserved(bo, vmf,
>> + drm_vma_node_start(&bo->base.vma_node),
>> +                       vmf->vma->vm_page_prot,
>>                          TTM_BO_VM_NUM_PREFAULT, 1);
>>       if (ret == VM_FAULT_RETRY && !(vmf->flags & 
>> FAULT_FLAG_RETRY_NOWAIT))
>>           goto unlock_mclk;
>> diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c 
>> b/drivers/gpu/drm/ttm/ttm_bo_vm.c
>> index b31b18058965..ed00ccf1376e 100644
>> --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
>> +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
>> @@ -42,7 +42,7 @@
>>   #include <linux/mem_encrypt.h>
>>     static vm_fault_t ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
>> -                struct vm_fault *vmf)
>> +                       struct vm_fault *vmf)
>>   {
>>       vm_fault_t ret = 0;
>>       int err = 0;
>> @@ -122,7 +122,8 @@ static unsigned long ttm_bo_io_mem_pfn(struct 
>> ttm_buffer_object *bo,
>>    * Return:
>>    *    0 on success and the bo was reserved.
>>    *    VM_FAULT_RETRY if blocking wait.
>> - *    VM_FAULT_NOPAGE if blocking wait and retrying was not allowed.
>> + *    VM_FAULT_NOPAGE if blocking wait and retrying was not allowed, 
>> or wait interrupted.
>> + *    VM_FAULT_SIGBUS if wait on bo->moving failed for reason other 
>> than a signal.
>>    */
>>   vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
>>                    struct vm_fault *vmf)
>> @@ -254,7 +255,9 @@ static vm_fault_t ttm_bo_vm_insert_huge(struct 
>> vm_fault *vmf,
>>     /**
>>    * ttm_bo_vm_fault_reserved - TTM fault helper
>> + * @bo: The buffer object
>>    * @vmf: The struct vm_fault given as argument to the fault callback
>> + * @mmap_base: The base of the mmap, to which the @vmf fault is 
>> relative to.
>>    * @prot: The page protection to be used for this memory area.
>>    * @num_prefault: Maximum number of prefault pages. The caller may 
>> want to
>>    * specify this based on madvice settings and the size of the GPU 
>> object
>> @@ -265,19 +268,28 @@ static vm_fault_t ttm_bo_vm_insert_huge(struct 
>> vm_fault *vmf,
>>    * memory backing the buffer object, and then returns a return code
>>    * instructing the caller to retry the page access.
>>    *
>> + * This function ensures any pipelined wait is finished.
>> + *
>> + * WARNING:
>> + * On VM_FAULT_RETRY, the bo will be unlocked by this function when
>> + * #FAULT_FLAG_RETRY_NOWAIT is not set inside @vmf->flags. In this
>> + * case, the caller should not unlock the @bo.
>> + *
>>    * Return:
>> - *   VM_FAULT_NOPAGE on success or pending signal
>> + *   0 on success.
>> + *   VM_FAULT_NOPAGE on pending signal
>>    *   VM_FAULT_SIGBUS on unspecified error
>>    *   VM_FAULT_OOM on out-of-memory
>> - *   VM_FAULT_RETRY if retryable wait
>> + *   VM_FAULT_RETRY if retryable wait, see WARNING above.
>>    */
>> -vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
>> +vm_fault_t ttm_bo_vm_fault_reserved(struct ttm_buffer_object *bo,
>> +                    struct vm_fault *vmf,
>> +                    unsigned long mmap_base,
>>                       pgprot_t prot,
>>                       pgoff_t num_prefault,
>>                       pgoff_t fault_page_size)
>>   {
>>       struct vm_area_struct *vma = vmf->vma;
>> -    struct ttm_buffer_object *bo = vma->vm_private_data;
>>       struct ttm_device *bdev = bo->bdev;
>>       unsigned long page_offset;
>>       unsigned long page_last;
>> @@ -286,15 +298,11 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct 
>> vm_fault *vmf,
>>       struct page *page;
>>       int err;
>>       pgoff_t i;
>> -    vm_fault_t ret = VM_FAULT_NOPAGE;
>> +    vm_fault_t ret;
>>       unsigned long address = vmf->address;
>>   -    /*
>> -     * Wait for buffer data in transit, due to a pipelined
>> -     * move.
>> -     */
>>       ret = ttm_bo_vm_fault_idle(bo, vmf);
>> -    if (unlikely(ret != 0))
>> +    if (ret)
>>           return ret;
>>         err = ttm_mem_io_reserve(bdev, &bo->mem);
>> @@ -302,9 +310,8 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct 
>> vm_fault *vmf,
>>           return VM_FAULT_SIGBUS;
>>         page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
>> -        vma->vm_pgoff - drm_vma_node_start(&bo->base.vma_node);
>> -    page_last = vma_pages(vma) + vma->vm_pgoff -
>> -        drm_vma_node_start(&bo->base.vma_node);
>> +        vma->vm_pgoff - mmap_base;
>> +    page_last = vma_pages(vma) + vma->vm_pgoff - mmap_base;
>>         if (unlikely(page_offset >= bo->mem.num_pages))
>>           return VM_FAULT_SIGBUS;
>> @@ -344,8 +351,7 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct 
>> vm_fault *vmf,
>>               } else if (unlikely(!page)) {
>>                   break;
>>               }
>> -            page->index = drm_vma_node_start(&bo->base.vma_node) +
>> -                page_offset;
>> +            page->index = mmap_base + page_offset;
>>               pfn = page_to_pfn(page);
>>           }
>>   @@ -392,7 +398,10 @@ vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf)
>>           return ret;
>>         prot = vma->vm_page_prot;
>> -    ret = ttm_bo_vm_fault_reserved(vmf, prot, 
>> TTM_BO_VM_NUM_PREFAULT, 1);
>> +    ret = ttm_bo_vm_fault_reserved(bo, vmf,
>> + drm_vma_node_start(&bo->base.vma_node),
>> +                       prot, TTM_BO_VM_NUM_PREFAULT, 1);
>> +
>>       if (ret == VM_FAULT_RETRY && !(vmf->flags & 
>> FAULT_FLAG_RETRY_NOWAIT))
>>           return ret;
>>   @@ -460,22 +469,16 @@ static int ttm_bo_vm_access_kmap(struct 
>> ttm_buffer_object *bo,
>>       return len;
>>   }
>>   -int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
>> -             void *buf, int len, int write)
>> +int ttm_bo_vm_access_reserved(struct ttm_buffer_object *bo,
>> +                  struct vm_area_struct *vma,
>> +                  unsigned long offset,
>> +                  void *buf, int len, int write)
>>   {
>> -    struct ttm_buffer_object *bo = vma->vm_private_data;
>> -    unsigned long offset = (addr) - vma->vm_start +
>> -        ((vma->vm_pgoff - drm_vma_node_start(&bo->base.vma_node))
>> -         << PAGE_SHIFT);
>>       int ret;
>>         if (len < 1 || (offset + len) >> PAGE_SHIFT > bo->mem.num_pages)
>>           return -EIO;
>>   -    ret = ttm_bo_reserve(bo, true, false, NULL);
>> -    if (ret)
>> -        return ret;
>> -
>>       switch (bo->mem.mem_type) {
>>       case TTM_PL_SYSTEM:
>>           if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
>> @@ -485,16 +488,33 @@ int ttm_bo_vm_access(struct vm_area_struct 
>> *vma, unsigned long addr,
>>           }
>>           fallthrough;
>>       case TTM_PL_TT:
>> -        ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write);
>> -        break;
>> +        return ttm_bo_vm_access_kmap(bo, offset, buf, len, write);
>>       default:
>>           if (bo->bdev->funcs->access_memory)
>> -            ret = bo->bdev->funcs->access_memory(
>> +            return bo->bdev->funcs->access_memory(
>>                   bo, offset, buf, len, write);
>>           else
>> -            ret = -EIO;
>> +            return -EIO;
>>       }
>>   +    return ret;
>> +}
>> +EXPORT_SYMBOL(ttm_bo_vm_access_reserved);
>> +
>> +int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
>> +             void *buf, int len, int write)
>> +{
>> +    struct ttm_buffer_object *bo = vma->vm_private_data;
>> +    unsigned long offset = (addr) - vma->vm_start +
>> +        ((vma->vm_pgoff - drm_vma_node_start(&bo->base.vma_node))
>> +         << PAGE_SHIFT);
>> +    int ret;
>> +
>> +    ret = ttm_bo_reserve(bo, true, false, NULL);
>> +    if (ret)
>> +        return ret;
>> +
>> +    ret = ttm_bo_vm_access_reserved(bo, vma, offset, buf, len, write);
>>       ttm_bo_unreserve(bo);
>>         return ret;
>> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c 
>> b/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c
>> index 45c9c6a7f1d6..56ecace0cf5c 100644
>> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c
>> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c
>> @@ -477,7 +477,9 @@ vm_fault_t vmw_bo_vm_fault(struct vm_fault *vmf)
>>       else
>>           prot = vm_get_page_prot(vma->vm_flags);
>>   -    ret = ttm_bo_vm_fault_reserved(vmf, prot, num_prefault, 1);
>> +    ret = ttm_bo_vm_fault_reserved(bo, vmf,
>> + drm_vma_node_start(&bo->base.vma_node),
>> +                       prot, num_prefault, 1);
>>       if (ret == VM_FAULT_RETRY && !(vmf->flags & 
>> FAULT_FLAG_RETRY_NOWAIT))
>>           return ret;
>>   @@ -546,7 +548,9 @@ vm_fault_t vmw_bo_vm_huge_fault(struct vm_fault 
>> *vmf,
>>           prot = vm_get_page_prot(vma->vm_flags);
>>       }
>>   -    ret = ttm_bo_vm_fault_reserved(vmf, prot, 1, fault_page_size);
>> +    ret = ttm_bo_vm_fault_reserved(bo, vmf,
>> + drm_vma_node_start(&bo->base.vma_node),
>> +                       prot, 1, fault_page_size);
>>       if (ret == VM_FAULT_RETRY && !(vmf->flags & 
>> FAULT_FLAG_RETRY_NOWAIT))
>>           return ret;
>>   diff --git a/include/drm/ttm/ttm_bo_api.h 
>> b/include/drm/ttm/ttm_bo_api.h
>> index 639521880c29..434f91f1fdbf 100644
>> --- a/include/drm/ttm/ttm_bo_api.h
>> +++ b/include/drm/ttm/ttm_bo_api.h
>> @@ -605,7 +605,9 @@ int ttm_mem_evict_first(struct ttm_device *bdev,
>>   vm_fault_t ttm_bo_vm_reserve(struct ttm_buffer_object *bo,
>>                    struct vm_fault *vmf);
>>   -vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
>> +vm_fault_t ttm_bo_vm_fault_reserved(struct ttm_buffer_object *bo,
>> +                    struct vm_fault *vmf,
>> +                    unsigned long mmap_base,
>>                       pgprot_t prot,
>>                       pgoff_t num_prefault,
>>                       pgoff_t fault_page_size);
>> @@ -616,6 +618,11 @@ void ttm_bo_vm_open(struct vm_area_struct *vma);
>>     void ttm_bo_vm_close(struct vm_area_struct *vma);
>>   +int ttm_bo_vm_access_reserved(struct ttm_buffer_object *bo,
>> +                  struct vm_area_struct *vma,
>> +                  unsigned long offset,
>> +                  void *buf, int len, int write);
>> +
>>   int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
>>                void *buf, int len, int write);
>>   bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all);



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