Hi

Am 15.04.21 um 13:38 schrieb Christian König:
> Am 15.04.21 um 12:17 schrieb Thomas Zimmermann:
>> Moving the driver-specific mmap code into a GEM object function allows
>> for using DRM helpers for various mmap callbacks.
>>
>> This change resolves several inconsistencies between regular mmap and
>> prime-based mmap. The vm_ops field in vma is now set for all mmap'ed
>> areas. Previously it way only set for regular mmap calls, prime-based
>> mmap used TTM's default vm_ops. The function amdgpu_verify_access() is
>> no longer being called and therefore removed by this patch.
>>
>> As a side effect, amdgpu_ttm_vm_ops and amdgpu_ttm_fault() are now
>> implemented in amdgpu's GEM code.
>>
>> v2:
>>     * rename amdgpu_ttm_vm_ops and amdgpu_ttm_fault() to
>>       amdgpu_gem_vm_ops and amdgpu_gem_fault() (Christian)
>>     * the check for kfd_bo has meanwhile been removed
>>
>> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> 
> [SNIP]
>> +static int amdgpu_gem_prime_mmap(struct drm_gem_object *obj, struct 
>> vm_area_struct *vma)
>> +{
> 
> Mhm, just double checking this function is now a core GEM function and 
> not prime specific?
> 
> If yes maybe drop the _prime part.

No problem, but other functions in the GEM callbacks are also named 
_prime_. Probably needs a clean-up.

> 
>> +    struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
>> +    struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
>> +    unsigned long asize = amdgpu_bo_size(bo);
>> +
>> +    if (!vma->vm_file)
>> +        return -ENODEV;
>> +
>> +    if (!adev)
>> +        return -ENODEV;
>> +
>> +    /* Check for valid size. */
>> +    if (asize < vma->vm_end - vma->vm_start)
>> +        return -EINVAL;
> 
> Shouldn't we have that check in the common code?

It's at [1]. I didn't really bother about tidying up the checks 
themselves. We can drop all these except for the usermm branch below. 
Same for the radeon patch.

Best regards
Thomas

[1] 
https://elixir.bootlin.com/linux/v5.12-rc7/source/drivers/gpu/drm/drm_gem.c#L1059

> 
> Apart from that looks good to me.
> 
> Christian.
> 
>> +
>> +    if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm) ||
>> +        (bo->flags & AMDGPU_GEM_CREATE_NO_CPU_ACCESS)) {
>> +        return -EPERM;
>> +    }
>> +
>> +    return drm_gem_ttm_mmap(obj, vma);
>> +}
>> +
>>   static const struct drm_gem_object_funcs amdgpu_gem_object_funcs = {
>>       .free = amdgpu_gem_object_free,
>>       .open = amdgpu_gem_object_open,
>> @@ -212,6 +266,8 @@ static const struct drm_gem_object_funcs 
>> amdgpu_gem_object_funcs = {
>>       .export = amdgpu_gem_prime_export,
>>       .vmap = drm_gem_ttm_vmap,
>>       .vunmap = drm_gem_ttm_vunmap,
>> +    .mmap = amdgpu_gem_prime_mmap,
>> +    .vm_ops = &amdgpu_gem_vm_ops,
>>   };
>>   /*
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> index 1485f33c3cc7..d4083c19402b 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> @@ -152,25 +152,6 @@ static void amdgpu_evict_flags(struct 
>> ttm_buffer_object *bo,
>>       *placement = abo->placement;
>>   }
>> -/**
>> - * amdgpu_verify_access - Verify access for a mmap call
>> - *
>> - * @bo:    The buffer object to map
>> - * @filp: The file pointer from the process performing the mmap
>> - *
>> - * This is called by ttm_bo_mmap() to verify whether a process
>> - * has the right to mmap a BO to their process space.
>> - */
>> -static int amdgpu_verify_access(struct ttm_buffer_object *bo, struct 
>> file *filp)
>> -{
>> -    struct amdgpu_bo *abo = ttm_to_amdgpu_bo(bo);
>> -
>> -    if (amdgpu_ttm_tt_get_usermm(bo->ttm))
>> -        return -EPERM;
>> -    return drm_vma_node_verify_access(&abo->tbo.base.vma_node,
>> -                      filp->private_data);
>> -}
>> -
>>   /**
>>    * amdgpu_ttm_map_buffer - Map memory into the GART windows
>>    * @bo: buffer object to map
>> @@ -1522,7 +1503,6 @@ static struct ttm_device_funcs amdgpu_bo_driver = {
>>       .eviction_valuable = amdgpu_ttm_bo_eviction_valuable,
>>       .evict_flags = &amdgpu_evict_flags,
>>       .move = &amdgpu_bo_move,
>> -    .verify_access = &amdgpu_verify_access,
>>       .delete_mem_notify = &amdgpu_bo_delete_mem_notify,
>>       .release_notify = &amdgpu_bo_release_notify,
>>       .io_mem_reserve = &amdgpu_ttm_io_mem_reserve,
>> @@ -1897,50 +1877,6 @@ void amdgpu_ttm_set_buffer_funcs_status(struct 
>> amdgpu_device *adev, bool enable)
>>       adev->mman.buffer_funcs_enabled = enable;
>>   }
>> -static vm_fault_t amdgpu_ttm_fault(struct vm_fault *vmf)
>> -{
>> -    struct ttm_buffer_object *bo = vmf->vma->vm_private_data;
>> -    vm_fault_t ret;
>> -
>> -    ret = ttm_bo_vm_reserve(bo, vmf);
>> -    if (ret)
>> -        return ret;
>> -
>> -    ret = amdgpu_bo_fault_reserve_notify(bo);
>> -    if (ret)
>> -        goto unlock;
>> -
>> -    ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot,
>> -                       TTM_BO_VM_NUM_PREFAULT, 1);
>> -    if (ret == VM_FAULT_RETRY && !(vmf->flags & 
>> FAULT_FLAG_RETRY_NOWAIT))
>> -        return ret;
>> -
>> -unlock:
>> -    dma_resv_unlock(bo->base.resv);
>> -    return ret;
>> -}
>> -
>> -static const struct vm_operations_struct amdgpu_ttm_vm_ops = {
>> -    .fault = amdgpu_ttm_fault,
>> -    .open = ttm_bo_vm_open,
>> -    .close = ttm_bo_vm_close,
>> -    .access = ttm_bo_vm_access
>> -};
>> -
>> -int amdgpu_mmap(struct file *filp, struct vm_area_struct *vma)
>> -{
>> -    struct drm_file *file_priv = filp->private_data;
>> -    struct amdgpu_device *adev = drm_to_adev(file_priv->minor->dev);
>> -    int r;
>> -
>> -    r = ttm_bo_mmap(filp, vma, &adev->mman.bdev);
>> -    if (unlikely(r != 0))
>> -        return r;
>> -
>> -    vma->vm_ops = &amdgpu_ttm_vm_ops;
>> -    return 0;
>> -}
>> -
>>   int amdgpu_copy_buffer(struct amdgpu_ring *ring, uint64_t src_offset,
>>                  uint64_t dst_offset, uint32_t byte_count,
>>                  struct dma_resv *resv,
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>> index dec0db8b0b13..6e51faad7371 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>> @@ -146,7 +146,6 @@ int amdgpu_fill_buffer(struct amdgpu_bo *bo,
>>               struct dma_resv *resv,
>>               struct dma_fence **fence);
>> -int amdgpu_mmap(struct file *filp, struct vm_area_struct *vma);
>>   int amdgpu_ttm_alloc_gart(struct ttm_buffer_object *bo);
>>   int amdgpu_ttm_recover_gart(struct ttm_buffer_object *tbo);
>>   uint64_t amdgpu_ttm_domain_start(struct amdgpu_device *adev, 
>> uint32_t type);
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer