Re: [PATCH v5 5/6] drm/amdgpu: Add helper to alloc GART entries

[Philip Yang]

On 2025-12-15 10:14, Christian König wrote:
On 12/10/25 00:43, Philip Yang wrote:
Add helper amdgpu_gtt_mgr_alloc/free_entries, export the configurable drm_mm
allocator parameters to caller.

Signed-off-by: Philip Yang <philip.y...@amd.com>
---
  drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c | 27 +++++++++++++++++++++
  drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h     |  7 ++++++
  2 files changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
index 895c1e4c6747..d21c7187e4aa 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
@@ -321,3 +321,30 @@ void amdgpu_gtt_mgr_fini(struct amdgpu_device *adev)
        ttm_resource_manager_cleanup(man);
        ttm_set_driver_manager(&adev->mman.bdev, TTM_PL_TT, NULL);
  }
+
+int amdgpu_gtt_mgr_alloc_entries(struct amdgpu_gtt_mgr *mgr,
+                                struct drm_mm_node *node,
+                                u64 num_pages, u64 alignment,
+                                unsigned long color,
+                                enum drm_mm_insert_mode mode)
The color is unused as far as I remember and the insert mode should be 
hardcoded, at least I don't see a good reason to expose that.

Any specific reason that was added here?
The color parameter removed in next version, Eric pointed out same 
issue, the new alloc color is hardcoded inside alloc_entries.

Thanks,
Philip

Regards,
Christian.

+{
+       struct amdgpu_device *adev = container_of(mgr, typeof(*adev), 
mman.gtt_mgr);
+       int r;
+
+       spin_lock(&mgr->lock);
+       r = drm_mm_insert_node_in_range(&mgr->mm, node, num_pages,
+                                       alignment, color, 0,
+                                       adev->gmc.gart_size >> PAGE_SHIFT,
+                                       mode);
+       spin_unlock(&mgr->lock);
+       return r;
+}
+
+void amdgpu_gtt_mgr_free_entries(struct amdgpu_gtt_mgr *mgr,
+                                struct drm_mm_node *mm_node)
+{
+       spin_lock(&mgr->lock);
+       if (drm_mm_node_allocated(mm_node))
+               drm_mm_remove_node(mm_node);
+       spin_unlock(&mgr->lock);
+}
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
index 72488124aa59..28511e66d364 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
@@ -141,6 +141,13 @@ void amdgpu_vram_mgr_fini(struct amdgpu_device *adev);
  bool amdgpu_gtt_mgr_has_gart_addr(struct ttm_resource *mem);
  void amdgpu_gtt_mgr_recover(struct amdgpu_gtt_mgr *mgr);
  
+int amdgpu_gtt_mgr_alloc_entries(struct amdgpu_gtt_mgr *mgr,
+                                struct drm_mm_node *node,
+                                u64 num_pages, u64 alignment,
+                                unsigned long color,
+                                enum drm_mm_insert_mode mode);
+void amdgpu_gtt_mgr_free_entries(struct amdgpu_gtt_mgr *mgr,
+                                struct drm_mm_node *mm_node);
  uint64_t amdgpu_preempt_mgr_usage(struct ttm_resource_manager *man);
  
  u64 amdgpu_vram_mgr_bo_visible_size(struct amdgpu_bo *bo);