drm/amdkfd: Fix BO offset for multi-VMA page migration

svm_migrate_ram_to_vram migrates a prange from sys ram to vram. The prange may
cross multiple vma. Need remember current dst vram offset in the TTM resource for
each migration.

v2: squash in warning fix (Alex)
Signed-off-by: Xiaogang Chen <Xiaogang.Chen@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdkfd/kfd_migrate.c

@@ -289,7 +289,7 @@ static unsigned long svm_migrate_unsuccessful_pages(struct migrate_vma *migrate)
 static int
 svm_migrate_copy_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 			 struct migrate_vma *migrate, struct dma_fence **mfence,
-			 dma_addr_t *scratch)
+			 dma_addr_t *scratch, uint64_t ttm_res_offset)
 {
 	uint64_t npages = migrate->npages;
 	struct device *dev = adev->dev;
@@ -299,8 +299,8 @@ svm_migrate_copy_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 	uint64_t i, j;
 	int r;
 
-	pr_debug("svms 0x%p [0x%lx 0x%lx]\n", prange->svms, prange->start,
-		 prange->last);
+	pr_debug("svms 0x%p [0x%lx 0x%lx 0x%llx]\n", prange->svms, prange->start,
+		 prange->last, ttm_res_offset);
 
 	src = scratch;
 	dst = (uint64_t *)(scratch + npages);
@@ -311,7 +311,7 @@ svm_migrate_copy_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 		goto out;
 	}
 
-	amdgpu_res_first(prange->ttm_res, prange->offset << PAGE_SHIFT,
+	amdgpu_res_first(prange->ttm_res, ttm_res_offset,
 			 npages << PAGE_SHIFT, &cursor);
 	for (i = j = 0; i < npages; i++) {
 		struct page *spage;
@@ -398,7 +398,7 @@ svm_migrate_copy_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 static long
 svm_migrate_vma_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 			struct vm_area_struct *vma, uint64_t start,
-			uint64_t end, uint32_t trigger)
+			uint64_t end, uint32_t trigger, uint64_t ttm_res_offset)
 {
 	struct kfd_process *p = container_of(prange->svms, struct kfd_process, svms);
 	uint64_t npages = (end - start) >> PAGE_SHIFT;
@@ -451,7 +451,7 @@ svm_migrate_vma_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 	else
 		pr_debug("0x%lx pages migrated\n", cpages);
 
-	r = svm_migrate_copy_to_vram(adev, prange, &migrate, &mfence, scratch);
+	r = svm_migrate_copy_to_vram(adev, prange, &migrate, &mfence, scratch, ttm_res_offset);
 	migrate_vma_pages(&migrate);
 
 	pr_debug("successful/cpages/npages 0x%lx/0x%lx/0x%lx\n",
@@ -499,6 +499,7 @@ svm_migrate_ram_to_vram(struct svm_range *prange, uint32_t best_loc,
 	unsigned long addr, start, end;
 	struct vm_area_struct *vma;
 	struct amdgpu_device *adev;
+	uint64_t ttm_res_offset;
 	unsigned long cpages = 0;
 	long r = 0;
 
@@ -519,6 +520,7 @@ svm_migrate_ram_to_vram(struct svm_range *prange, uint32_t best_loc,
 
 	start = prange->start << PAGE_SHIFT;
 	end = (prange->last + 1) << PAGE_SHIFT;
+	ttm_res_offset = prange->offset << PAGE_SHIFT;
 
 	for (addr = start; addr < end;) {
 		unsigned long next;
@@ -528,13 +530,14 @@ svm_migrate_ram_to_vram(struct svm_range *prange, uint32_t best_loc,
 			break;
 
 		next = min(vma->vm_end, end);
-		r = svm_migrate_vma_to_vram(adev, prange, vma, addr, next, trigger);
+		r = svm_migrate_vma_to_vram(adev, prange, vma, addr, next, trigger, ttm_res_offset);
 		if (r < 0) {
 			pr_debug("failed %ld to migrate\n", r);
 			break;
 		} else {
 			cpages += r;
 		}
+		ttm_res_offset += next - addr;
 		addr = next;
 	}