[PATCH v2] amd/amdkfd: Set correct svm range actual loc after spliting

[Philip Yang]

After svm range partial migrating to system memory, unmap to cleanup the
corresponding dma_addr vram domain flag, otherwise the future split will
get incorrect vram_pages and actual loc.

After range spliting, set new range and old range actual_loc:
new range actual_loc is 0 if new->vram_pages is 0.
old range actual_loc is 0 if old->vram_pages - new->vram_pages == 0.

new range takes svm_bo ref only if vram_pages not equal to 0.

Signed-off-by: Philip Yang <Philip.Yang at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_migrate.c |  3 ++
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c     | 35 +++++++++++++++---------
 drivers/gpu/drm/amd/amdkfd/kfd_svm.h     |  3 +-
 3 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
index f856901055d3..e85bcda29db6 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
@@ -839,6 +839,9 @@ int svm_migrate_vram_to_ram(struct svm_range *prange, struct mm_struct *mm,
 			prange->actual_loc = 0;
 			svm_range_vram_node_free(prange);
 		}
+
+		svm_range_dma_unmap(prange, start_mgr - prange->start,
+				    last_mgr - start_mgr + 1);
 	}
 
 	return r < 0 ? r : 0;
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index cc24f30f88fb..2202bdcde057 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -254,6 +254,10 @@ void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
 		return;
 
 	for (i = offset; i < offset + npages; i++) {
+		if (dma_addr[i] & SVM_RANGE_VRAM_DOMAIN) {
+			dma_addr[i] = 0;
+			continue;
+		}
 		if (!svm_is_valid_dma_mapping_addr(dev, dma_addr[i]))
 			continue;
 		pr_debug_ratelimited("unmap 0x%llx\n", dma_addr[i] >> PAGE_SHIFT);
@@ -262,7 +266,8 @@ void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
 	}
 }
 
-void svm_range_dma_unmap(struct svm_range *prange)
+void svm_range_dma_unmap(struct svm_range *prange, unsigned long offset,
+			 unsigned long npages)
 {
 	struct kfd_process_device *pdd;
 	dma_addr_t *dma_addr;
@@ -284,7 +289,7 @@ void svm_range_dma_unmap(struct svm_range *prange)
 		}
 		dev = &pdd->dev->adev->pdev->dev;
 
-		svm_range_dma_unmap_dev(dev, dma_addr, 0, prange->npages);
+		svm_range_dma_unmap_dev(dev, dma_addr, offset, npages);
 	}
 }
 
@@ -299,7 +304,7 @@ static void svm_range_free(struct svm_range *prange, bool do_unmap)
 
 	svm_range_vram_node_free(prange);
 	if (do_unmap)
-		svm_range_dma_unmap(prange);
+		svm_range_dma_unmap(prange, 0, prange->npages);
 
 	if (do_unmap && !p->xnack_enabled) {
 		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
@@ -362,7 +367,6 @@ svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
 	INIT_LIST_HEAD(&prange->child_list);
 	atomic_set(&prange->invalid, 0);
 	prange->validate_timestamp = 0;
-	prange->vram_pages = 0;
 	mutex_init(&prange->migrate_mutex);
 	mutex_init(&prange->lock);
 
@@ -980,9 +984,14 @@ svm_range_split_pages(struct svm_range *new, struct svm_range *old,
 		if (r)
 			return r;
 	}
-	if (old->actual_loc)
+	if (old->actual_loc && new->vram_pages) {
 		old->vram_pages -= new->vram_pages;
-
+		new->actual_loc = old->actual_loc;
+		if (!old->vram_pages)
+			old->actual_loc = 0;
+	}
+	pr_debug("new->vram_pages 0x%llx loc 0x%x old->vram_pages 0x%llx loc 0x%x\n",
+		 new->vram_pages, new->actual_loc, old->vram_pages, old->actual_loc);
 	return 0;
 }
 
@@ -1002,13 +1011,14 @@ svm_range_split_nodes(struct svm_range *new, struct svm_range *old,
 		new->offset = old->offset + npages;
 	}
 
-	new->svm_bo = svm_range_bo_ref(old->svm_bo);
-	new->ttm_res = old->ttm_res;
-
-	spin_lock(&new->svm_bo->list_lock);
-	list_add(&new->svm_bo_list, &new->svm_bo->range_list);
-	spin_unlock(&new->svm_bo->list_lock);
+	if (new->vram_pages) {
+		new->svm_bo = svm_range_bo_ref(old->svm_bo);
+		new->ttm_res = old->ttm_res;
 
+		spin_lock(&new->svm_bo->list_lock);
+		list_add(&new->svm_bo_list, &new->svm_bo->range_list);
+		spin_unlock(&new->svm_bo->list_lock);
+	}
 	return 0;
 }
 
@@ -1058,7 +1068,6 @@ svm_range_split_adjust(struct svm_range *new, struct svm_range *old,
 	new->flags = old->flags;
 	new->preferred_loc = old->preferred_loc;
 	new->prefetch_loc = old->prefetch_loc;
-	new->actual_loc = old->actual_loc;
 	new->granularity = old->granularity;
 	new->mapped_to_gpu = old->mapped_to_gpu;
 	bitmap_copy(new->bitmap_access, old->bitmap_access, MAX_GPU_INSTANCE);
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
index 026863a0abcd..778f108911cd 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
@@ -182,7 +182,8 @@ void svm_range_add_list_work(struct svm_range_list *svms,
 void schedule_deferred_list_work(struct svm_range_list *svms);
 void svm_range_dma_unmap_dev(struct device *dev, dma_addr_t *dma_addr,
 			 unsigned long offset, unsigned long npages);
-void svm_range_dma_unmap(struct svm_range *prange);
+void svm_range_dma_unmap(struct svm_range *prange, unsigned long offset,
+			 unsigned long npages);
 int svm_range_get_info(struct kfd_process *p, uint32_t *num_svm_ranges,
 		       uint64_t *svm_priv_data_size);
 int kfd_criu_checkpoint_svm(struct kfd_process *p,
-- 
2.35.1