drm/exec: Remove the index parameter from drm_exec_for_each_locked_obj[_reverse]

Nobody makes any use of it. Possible internal future users can
instead use the _index variable. External users shouldn't use
it since the array it's pointing into is internal drm_exec state.

v2:
- Use a unique id for the loop variable (Christian)

Assisted-by: GitHub Copilot:claude-sonnet-4.6
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patch.msgid.link/20260520101616.41284-2-thomas.hellstrom@linux.intel.com

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

@@ -850,7 +850,6 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 	struct amdgpu_vm *vm = &fpriv->vm;
 	struct amdgpu_bo_list_entry *e;
 	struct drm_gem_object *obj;
-	unsigned long index;
 	unsigned int i;
 	int r;
 
@@ -961,7 +960,7 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 		goto out_free_user_pages;
 	}
 
-	drm_exec_for_each_locked_object(&p->exec, index, obj) {
+	drm_exec_for_each_locked_object(&p->exec, obj) {
 		r = amdgpu_cs_bo_validate(p, gem_to_amdgpu_bo(obj));
 		if (unlikely(r))
 			goto out_free_user_pages;
@@ -1201,7 +1200,6 @@ static int amdgpu_cs_sync_rings(struct amdgpu_cs_parser *p)
 	struct drm_gpu_scheduler *sched;
 	struct drm_gem_object *obj;
 	struct dma_fence *fence;
-	unsigned long index;
 	unsigned int i;
 	int r;
 
@@ -1212,7 +1210,7 @@ static int amdgpu_cs_sync_rings(struct amdgpu_cs_parser *p)
 		return r;
 	}
 
-	drm_exec_for_each_locked_object(&p->exec, index, obj) {
+	drm_exec_for_each_locked_object(&p->exec, obj) {
 		struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
 
 		struct dma_resv *resv = bo->tbo.base.resv;
@@ -1281,7 +1279,6 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
 	struct amdgpu_job *leader = p->gang_leader;
 	struct amdgpu_bo_list_entry *e;
 	struct drm_gem_object *gobj;
-	unsigned long index;
 	unsigned int i;
 	uint64_t seq;
 	int r;
@@ -1331,7 +1328,7 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
 	}
 
 	p->fence = dma_fence_get(&leader->base.s_fence->finished);
-	drm_exec_for_each_locked_object(&p->exec, index, gobj) {
+	drm_exec_for_each_locked_object(&p->exec, gobj) {
 
 		ttm_bo_move_to_lru_tail_unlocked(&gem_to_amdgpu_bo(gobj)->tbo);
 

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

@@ -121,7 +121,6 @@ int amdgpu_evf_mgr_rearm(struct amdgpu_eviction_fence_mgr *evf_mgr,
 {
 	struct amdgpu_eviction_fence *ev_fence;
 	struct drm_gem_object *obj;
-	unsigned long index;
 
 	/* Create and initialize a new eviction fence */
 	ev_fence = kzalloc_obj(*ev_fence);
@@ -140,7 +139,7 @@ int amdgpu_evf_mgr_rearm(struct amdgpu_eviction_fence_mgr *evf_mgr,
 	evf_mgr->ev_fence = &ev_fence->base;
 
 	/* And add it to all existing BOs */
-	drm_exec_for_each_locked_object(exec, index, obj) {
+	drm_exec_for_each_locked_object(exec, obj) {
 		struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
 
 		amdgpu_evf_mgr_attach_fence(evf_mgr, bo);

drivers/gpu/drm/drm_exec.c

@@ -24,7 +24,6 @@
  *
  *	struct drm_gem_object *obj;
  *	struct drm_exec exec;
- *	unsigned long index;
  *	int ret;
  *
  *	drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT);
@@ -40,7 +39,7 @@
  *			goto error;
  *	}
  *
- *	drm_exec_for_each_locked_object(&exec, index, obj) {
+ *	drm_exec_for_each_locked_object(&exec, obj) {
  *		dma_resv_add_fence(obj->resv, fence, DMA_RESV_USAGE_READ);
  *		...
  *	}
@@ -56,9 +55,8 @@
 static void drm_exec_unlock_all(struct drm_exec *exec)
 {
 	struct drm_gem_object *obj;
-	unsigned long index;
 
-	drm_exec_for_each_locked_object_reverse(exec, index, obj) {
+	drm_exec_for_each_locked_object_reverse(exec, obj) {
 		dma_resv_unlock(obj->resv);
 		drm_gem_object_put(obj);
 	}

drivers/gpu/drm/drm_gpuvm.c

@@ -1553,9 +1553,8 @@ drm_gpuvm_resv_add_fence(struct drm_gpuvm *gpuvm,
 			 enum dma_resv_usage extobj_usage)
 {
 	struct drm_gem_object *obj;
-	unsigned long index;
 
-	drm_exec_for_each_locked_object(exec, index, obj) {
+	drm_exec_for_each_locked_object(exec, obj) {
 		dma_resv_assert_held(obj->resv);
 		dma_resv_add_fence(obj->resv, fence,
 				   drm_gpuvm_is_extobj(gpuvm, obj) ?

drivers/gpu/drm/xe/xe_vm.c

@@ -373,7 +373,6 @@ int xe_vm_validate_rebind(struct xe_vm *vm, struct drm_exec *exec,
 			  unsigned int num_fences)
 {
 	struct drm_gem_object *obj;
-	unsigned long index;
 	int ret;
 
 	do {
@@ -386,7 +385,7 @@ int xe_vm_validate_rebind(struct xe_vm *vm, struct drm_exec *exec,
 			return ret;
 	} while (!list_empty(&vm->gpuvm.evict.list));
 
-	drm_exec_for_each_locked_object(exec, index, obj) {
+	drm_exec_for_each_locked_object(exec, obj) {
 		ret = dma_resv_reserve_fences(obj->resv, num_fences);
 		if (ret)
 			return ret;

include/drm/drm_exec.h

@@ -65,31 +65,35 @@ drm_exec_obj(struct drm_exec *exec, unsigned long index)
 	return index < exec->num_objects ? exec->objects[index] : NULL;
 }
 
+/* Helper for drm_exec_for_each_locked_object(). Internal use only. */
+#define __drm_exec_for_each_locked_object(exec, obj, __index)		\
+	for (unsigned long __index = 0; ((obj) = drm_exec_obj(exec, __index)); ++__index)
 /**
  * drm_exec_for_each_locked_object - iterate over all the locked objects
  * @exec: drm_exec object
- * @index: unsigned long index for the iteration
  * @obj: the current GEM object
  *
  * Iterate over all the locked GEM objects inside the drm_exec object.
  */
-#define drm_exec_for_each_locked_object(exec, index, obj)		\
-	for ((index) = 0; ((obj) = drm_exec_obj(exec, index)); ++(index))
+#define drm_exec_for_each_locked_object(exec, obj)			\
+	__drm_exec_for_each_locked_object(exec, obj, __UNIQUE_ID(drm_exec))
 
+/* Helper for drm_exec_for_each_locked_object_reverse(). Internal use only. */
+#define __drm_exec_for_each_locked_object_reverse(exec, obj, __index)	\
+	for (unsigned long __index = (exec)->num_objects - 1;		\
+	     ((obj) = drm_exec_obj(exec, __index)); --__index)
 /**
  * drm_exec_for_each_locked_object_reverse - iterate over all the locked
  * objects in reverse locking order
  * @exec: drm_exec object
- * @index: unsigned long index for the iteration
  * @obj: the current GEM object
  *
  * Iterate over all the locked GEM objects inside the drm_exec object in
- * reverse locking order. Note that @index may go below zero and wrap,
+ * reverse locking order. Note that the internal index may wrap around,
  * but that will be caught by drm_exec_obj(), returning a NULL object.
  */
-#define drm_exec_for_each_locked_object_reverse(exec, index, obj)	\
-	for ((index) = (exec)->num_objects - 1;				\
-	     ((obj) = drm_exec_obj(exec, index)); --(index))
+#define drm_exec_for_each_locked_object_reverse(exec, obj)		\
+	__drm_exec_for_each_locked_object_reverse(exec, obj, __UNIQUE_ID(drm_exec))
 
 /**
  * drm_exec_until_all_locked - loop until all GEM objects are locked