drm/amdgpu: Add amdgpu_bo_is_vm_bo helper

Help code readability by replacing a bunch of:

bo->tbo.base.resv == vm->root.bo->tbo.base.resv

With:

amdgpu_vm_is_bo_always_valid(vm, bo)

No functional changes.

v2:
 * Rename helper and move to amdgpu_vm. (Christian)

v3:
 * Use Christian's kerneldoc.

v4:
 * Fixed logic inversion in amdgpu_vm_bo_get_memory.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c

@@ -174,7 +174,7 @@ static int amdgpu_gem_object_open(struct drm_gem_object *obj,
 		return -EPERM;
 
 	if (abo->flags & AMDGPU_GEM_CREATE_VM_ALWAYS_VALID &&
-	    abo->tbo.base.resv != vm->root.bo->tbo.base.resv)
+	    !amdgpu_vm_is_bo_always_valid(vm, abo))
 		return -EPERM;
 
 	r = amdgpu_bo_reserve(abo, false);

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c

@@ -333,7 +333,7 @@ void amdgpu_vm_bo_base_init(struct amdgpu_vm_bo_base *base,
 	base->next = bo->vm_bo;
 	bo->vm_bo = base;
 
-	if (bo->tbo.base.resv != vm->root.bo->tbo.base.resv)
+	if (!amdgpu_vm_is_bo_always_valid(vm, bo))
 		return;
 
 	dma_resv_assert_held(vm->root.bo->tbo.base.resv);
@@ -1101,13 +1101,13 @@ static void amdgpu_vm_bo_get_memory(struct amdgpu_bo_va *bo_va,
 	 * For now ignore BOs which are currently locked and potentially
 	 * changing their location.
 	 */
-	if (bo->tbo.base.resv != vm->root.bo->tbo.base.resv &&
+	if (!amdgpu_vm_is_bo_always_valid(vm, bo) &&
 	    !dma_resv_trylock(bo->tbo.base.resv))
 		return;
 
 	amdgpu_bo_get_memory(bo, stats);
-	if (bo->tbo.base.resv != vm->root.bo->tbo.base.resv)
-	    dma_resv_unlock(bo->tbo.base.resv);
+	if (!amdgpu_vm_is_bo_always_valid(vm, bo))
+		dma_resv_unlock(bo->tbo.base.resv);
 }
 
 void amdgpu_vm_get_memory(struct amdgpu_vm *vm,
@@ -1203,8 +1203,7 @@ int amdgpu_vm_bo_update(struct amdgpu_device *adev, struct amdgpu_bo_va *bo_va,
 		uncached = false;
 	}
 
-	if (clear || (bo && bo->tbo.base.resv ==
-		      vm->root.bo->tbo.base.resv))
+	if (clear || amdgpu_vm_is_bo_always_valid(vm, bo))
 		last_update = &vm->last_update;
 	else
 		last_update = &bo_va->last_pt_update;
@@ -1246,7 +1245,7 @@ int amdgpu_vm_bo_update(struct amdgpu_device *adev, struct amdgpu_bo_va *bo_va,
 	 * the evicted list so that it gets validated again on the
 	 * next command submission.
 	 */
-	if (bo && bo->tbo.base.resv == vm->root.bo->tbo.base.resv) {
+	if (amdgpu_vm_is_bo_always_valid(vm, bo)) {
 		uint32_t mem_type = bo->tbo.resource->mem_type;
 
 		if (!(bo->preferred_domains &
@@ -1640,10 +1639,9 @@ static void amdgpu_vm_bo_insert_map(struct amdgpu_device *adev,
 	if (mapping->flags & AMDGPU_PTE_PRT_FLAG(adev))
 		amdgpu_vm_prt_get(adev);
 
-	if (bo && bo->tbo.base.resv == vm->root.bo->tbo.base.resv &&
-	    !bo_va->base.moved) {
+	if (amdgpu_vm_is_bo_always_valid(vm, bo) && !bo_va->base.moved)
 		amdgpu_vm_bo_moved(&bo_va->base);
-	}
+
 	trace_amdgpu_vm_bo_map(bo_va, mapping);
 }
 
@@ -1942,7 +1940,7 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
 		if (before->flags & AMDGPU_PTE_PRT_FLAG(adev))
 			amdgpu_vm_prt_get(adev);
 
-		if (bo && bo->tbo.base.resv == vm->root.bo->tbo.base.resv &&
+		if (amdgpu_vm_is_bo_always_valid(vm, bo) &&
 		    !before->bo_va->base.moved)
 			amdgpu_vm_bo_moved(&before->bo_va->base);
 	} else {
@@ -1957,7 +1955,7 @@ int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
 		if (after->flags & AMDGPU_PTE_PRT_FLAG(adev))
 			amdgpu_vm_prt_get(adev);
 
-		if (bo && bo->tbo.base.resv == vm->root.bo->tbo.base.resv &&
+		if (amdgpu_vm_is_bo_always_valid(vm, bo) &&
 		    !after->bo_va->base.moved)
 			amdgpu_vm_bo_moved(&after->bo_va->base);
 	} else {
@@ -2037,7 +2035,7 @@ void amdgpu_vm_bo_del(struct amdgpu_device *adev,
 
 	if (bo) {
 		dma_resv_assert_held(bo->tbo.base.resv);
-		if (bo->tbo.base.resv == vm->root.bo->tbo.base.resv)
+		if (amdgpu_vm_is_bo_always_valid(vm, bo))
 			ttm_bo_set_bulk_move(&bo->tbo, NULL);
 
 		for (base = &bo_va->base.bo->vm_bo; *base;
@@ -2131,7 +2129,7 @@ void amdgpu_vm_bo_invalidate(struct amdgpu_device *adev,
 	for (bo_base = bo->vm_bo; bo_base; bo_base = bo_base->next) {
 		struct amdgpu_vm *vm = bo_base->vm;
 
-		if (evicted && bo->tbo.base.resv == vm->root.bo->tbo.base.resv) {
+		if (evicted && amdgpu_vm_is_bo_always_valid(vm, bo)) {
 			amdgpu_vm_bo_evicted(bo_base);
 			continue;
 		}
@@ -2142,7 +2140,7 @@ void amdgpu_vm_bo_invalidate(struct amdgpu_device *adev,
 
 		if (bo->tbo.type == ttm_bo_type_kernel)
 			amdgpu_vm_bo_relocated(bo_base);
-		else if (bo->tbo.base.resv == vm->root.bo->tbo.base.resv)
+		else if (amdgpu_vm_is_bo_always_valid(vm, bo))
 			amdgpu_vm_bo_moved(bo_base);
 		else
 			amdgpu_vm_bo_invalidated(bo_base);
@@ -3006,3 +3004,16 @@ void amdgpu_vm_update_fault_cache(struct amdgpu_device *adev,
 	xa_unlock_irqrestore(&adev->vm_manager.pasids, flags);
 }
 
+/**
+ * amdgpu_vm_is_bo_always_valid - check if the BO is VM always valid
+ *
+ * @vm: VM to test against.
+ * @abo: BO to be tested.
+ *
+ * Returns true if the BO shares the dma_resv object with the root PD and is
+ * always guaranteed to be valid inside the VM.
+ */
+bool amdgpu_vm_is_bo_always_valid(struct amdgpu_vm *vm, struct amdgpu_bo *bo)
+{
+	return bo && bo->tbo.base.resv == vm->root.bo->tbo.base.resv;
+}

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h

@@ -580,6 +580,8 @@ void amdgpu_debugfs_vm_bo_info(struct amdgpu_vm *vm, struct seq_file *m);
 
 int amdgpu_vm_pt_map_tables(struct amdgpu_device *adev, struct amdgpu_vm *vm);
 
+bool amdgpu_vm_is_bo_always_valid(struct amdgpu_vm *vm, struct amdgpu_bo *bo);
+
 /**
  * amdgpu_vm_tlb_seq - return tlb flush sequence number
  * @vm: the amdgpu_vm structure to query