[PATCH v5 01/23] Introduce drm_gpuvm_sm_map_ops_flags enums for sm_map_ops

[Ghimiray, Himal Prasad]

On 24-07-2025 06:13, Matthew Brost wrote:
> On Tue, Jul 22, 2025 at 03:38:14PM +0200, Danilo Krummrich wrote:
>> (Cc: Caterina)
>>
>> On Tue Jul 22, 2025 at 3:35 PM CEST, Himal Prasad Ghimiray wrote:
>>> - DRM_GPUVM_SM_MAP_NOT_MADVISE: Default sm_map operations for the input
>>>    range.
>>>
>>> - DRM_GPUVM_SKIP_GEM_OBJ_VA_SPLIT_MADVISE: This flag is used by
>>>    drm_gpuvm_sm_map_ops_create to iterate over GPUVMA's in the
>>> user-provided range and split the existing non-GEM object VMA if the
>>> start or end of the input range lies within it. The operations can
>>> create up to 2 REMAPS and 2 MAPs. The purpose of this operation is to be
>>> used by the Xe driver to assign attributes to GPUVMA's within the
>>> user-defined range. Unlike drm_gpuvm_sm_map_ops_flags in default mode,
>>> the operation with this flag will never have UNMAPs and
>>> merges, and can be without any final operations.
>>>
>>> v2
>>> - use drm_gpuvm_sm_map_ops_create with flags instead of defining new
>>>    ops_create (Danilo)
>>> - Add doc (Danilo)
>>>
>>> v3
>>> - Fix doc
>>> - Fix unmapping check
>>>
>>> v4
>>> - Fix mapping for non madvise ops
>>>
>>> Cc: Danilo Krummrich <dakr at redhat.com>
>>> Cc: Matthew Brost <matthew.brost at intel.com>
>>> Cc: Boris Brezillon <bbrezillon at kernel.org>
>>> Cc: <dri-devel at lists.freedesktop.org>
>>> Signed-off-by: Himal Prasad Ghimiray<himal.prasad.ghimiray at intel.com>
>>> ---
>>>   drivers/gpu/drm/drm_gpuvm.c            | 93 ++++++++++++++++++++------
>>>   drivers/gpu/drm/nouveau/nouveau_uvmm.c |  1 +
>>>   drivers/gpu/drm/xe/xe_vm.c             |  1 +
>>
>> What about the other drivers using GPUVM, aren't they affected by the changes?
>>
> 
> Yes, this seemly would break the build or other users. If the baseline
> includes the patch below that I suggest to pull in this is a moot point
> though.
> 
>>>   include/drm/drm_gpuvm.h                | 25 ++++++-
>>>   4 files changed, 98 insertions(+), 22 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/drm_gpuvm.c b/drivers/gpu/drm/drm_gpuvm.c
>>> index e89b932e987c..c7779588ea38 100644
>>> --- a/drivers/gpu/drm/drm_gpuvm.c
>>> +++ b/drivers/gpu/drm/drm_gpuvm.c
>>> @@ -2103,10 +2103,13 @@ static int
>>>   __drm_gpuvm_sm_map(struct drm_gpuvm *gpuvm,
>>>   		   const struct drm_gpuvm_ops *ops, void *priv,
>>>   		   u64 req_addr, u64 req_range,
>>> +		   enum drm_gpuvm_sm_map_ops_flags flags,
>>
>> Please coordinate with Boris and Caterina here. They're adding a new request
>> structure, struct drm_gpuvm_map_req.
>>
>> I think we can define it as
>>
>> 	struct drm_gpuvm_map_req {
>> 		struct drm_gpuva_op_map map;
>> 		struct drm_gpuvm_sm_map_ops_flags flags;
>> 	}
> 
> +1, I see the patch [2] and the suggested change to drm_gpuva_op_map
> [3]. Both patch and your suggestion look good to me.
> 
> Perhaps we try to accelerate [2] landing ahead of either series as
> overall just looks like a good cleanup which can be merged asap.
> 
> Himal - I'd rebase on top [2], with Danilo suggestion in [3] if this
> hasn't landed by your next rev.
> 
> [2] https://lore.kernel.org/all/20250707170442.1437009-4-caterina.shablia@collabora.com/
> [3] https://lore.kernel.org/all/DB61N61AKIJ3.FG7GUJBG386P@kernel.org/
> 

Sure will take care of this.
  >>
>> eventually.
>>
>> Please also coordinate on the changes in __drm_gpuvm_sm_map() below regarding
>> Caterina's series [1], it looks like they're conflicting.
>>
> 
> It looks pretty minor actually. I'm sure if really matter who this is
> race but yes, always good to coordinate.
> 
>> [1] https://lore.kernel.org/all/20250707170442.1437009-1-caterina.shablia@collabora.com/
>>
>>> +/**
>>> + * enum drm_gpuvm_sm_map_ops_flags - flags for drm_gpuvm split/merge ops
>>> + */
>>> +enum drm_gpuvm_sm_map_ops_flags {
>>> +	/**
>>> +	 * @DRM_GPUVM_SM_MAP_NOT_MADVISE: DEFAULT sm_map ops
>>> +	 */
>>> +	DRM_GPUVM_SM_MAP_NOT_MADVISE = 0,
>>
>> Why would we name this "NOT_MADVISE"? What if we add more flags for other
>> purposes?
>>
> 
> How about...
> 
> s/DRM_GPUVM_SM_MAP_NOT_MADVISE/DRM_GPUVM_SM_MAP_OPS_FLAG_NONE/

I was thinking DRM_GPUVM_SM_MAP_DEFAULT, but 
DRM_GPUVM_SM_MAP_OPS_FLAG_NONE looks better. will update it in next rev.

> 
>>> +	/**
>>> +	 * @DRM_GPUVM_SKIP_GEM_OBJ_VA_SPLIT_MADVISE: This flag is used by
>>> +	 * drm_gpuvm_sm_map_ops_create to iterate over GPUVMA's in the
>>> +	 * user-provided range and split the existing non-GEM object VMA if the
>>> +	 * start or end of the input range lies within it. The operations can
>>> +	 * create up to 2 REMAPS and 2 MAPs. Unlike drm_gpuvm_sm_map_ops_flags
>>> +	 * in default mode, the operation with this flag will never have UNMAPs and
>>> +	 * merges, and can be without any final operations.
>>> +	 */
>>> +	DRM_GPUVM_SKIP_GEM_OBJ_VA_SPLIT_MADVISE = BIT(0),
> 
> Then normalize this one...
> 
> s/DRM_GPUVM_SKIP_GEM_OBJ_VA_SPLIT_MADVISE/DRM_GPUVM_SM_MAP_OPS_FLAG_SPLIT_MADVISE/

Sure

> 
> Matt
> 
>>> +};