drm/ttm: cleanup coding style and implementation.

Only functional change is to always keep io_reserved_count up to date
for debugging even when it is not used otherwise.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/378242/

drivers/gpu/drm/ttm/ttm_bo_util.c

@@ -115,39 +115,35 @@ static int ttm_mem_io_evict(struct ttm_mem_type_manager *man)
 {
 	struct ttm_buffer_object *bo;
 
-	if (!man->use_io_reserve_lru || list_empty(&man->io_reserve_lru))
+	bo = list_first_entry_or_null(&man->io_reserve_lru,
+				      struct ttm_buffer_object,
+				      io_reserve_lru);
+	if (!bo)
 		return -ENOSPC;
 
-	bo = list_first_entry(&man->io_reserve_lru,
-			      struct ttm_buffer_object,
-			      io_reserve_lru);
 	list_del_init(&bo->io_reserve_lru);
 	ttm_bo_unmap_virtual_locked(bo);
-
 	return 0;
 }
 
-
 int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
 		       struct ttm_mem_reg *mem)
 {
 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
-	int ret = 0;
+	int ret;
+
+	if (mem->bus.io_reserved_count++)
+		return 0;
 
 	if (!bdev->driver->io_mem_reserve)
 		return 0;
-	if (likely(!man->use_io_reserve_lru))
-		return bdev->driver->io_mem_reserve(bdev, mem);
 
-	if (bdev->driver->io_mem_reserve &&
-	    mem->bus.io_reserved_count++ == 0) {
 retry:
-		ret = bdev->driver->io_mem_reserve(bdev, mem);
-		if (ret == -ENOSPC) {
-			ret = ttm_mem_io_evict(man);
-			if (ret == 0)
-				goto retry;
-		}
+	ret = bdev->driver->io_mem_reserve(bdev, mem);
+	if (ret == -ENOSPC) {
+		ret = ttm_mem_io_evict(man);
+		if (ret == 0)
+			goto retry;
 	}
 	return ret;
 }
@@ -155,35 +151,31 @@ int ttm_mem_io_reserve(struct ttm_bo_device *bdev,
 void ttm_mem_io_free(struct ttm_bo_device *bdev,
 		     struct ttm_mem_reg *mem)
 {
-	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
-
-	if (likely(!man->use_io_reserve_lru))
+	if (--mem->bus.io_reserved_count)
 		return;
 
-	if (bdev->driver->io_mem_reserve &&
-	    --mem->bus.io_reserved_count == 0 &&
-	    bdev->driver->io_mem_free)
-		bdev->driver->io_mem_free(bdev, mem);
+	if (!bdev->driver->io_mem_free)
+		return;
 
+	bdev->driver->io_mem_free(bdev, mem);
 }
 
 int ttm_mem_io_reserve_vm(struct ttm_buffer_object *bo)
 {
+	struct ttm_mem_type_manager *man = &bo->bdev->man[bo->mem.mem_type];
 	struct ttm_mem_reg *mem = &bo->mem;
 	int ret;
 
-	if (!mem->bus.io_reserved_vm) {
-		struct ttm_mem_type_manager *man =
-			&bo->bdev->man[mem->mem_type];
+	if (mem->bus.io_reserved_vm)
+		return 0;
 
-		ret = ttm_mem_io_reserve(bo->bdev, mem);
-		if (unlikely(ret != 0))
-			return ret;
-		mem->bus.io_reserved_vm = true;
-		if (man->use_io_reserve_lru)
-			list_add_tail(&bo->io_reserve_lru,
-				      &man->io_reserve_lru);
-	}
+	ret = ttm_mem_io_reserve(bo->bdev, mem);
+	if (unlikely(ret != 0))
+		return ret;
+	mem->bus.io_reserved_vm = true;
+	if (man->use_io_reserve_lru)
+		list_add_tail(&bo->io_reserve_lru,
+			      &man->io_reserve_lru);
 	return 0;
 }
 
@@ -191,15 +183,17 @@ void ttm_mem_io_free_vm(struct ttm_buffer_object *bo)
 {
 	struct ttm_mem_reg *mem = &bo->mem;
 
-	if (mem->bus.io_reserved_vm) {
-		mem->bus.io_reserved_vm = false;
-		list_del_init(&bo->io_reserve_lru);
-		ttm_mem_io_free(bo->bdev, mem);
-	}
+	if (!mem->bus.io_reserved_vm)
+		return;
+
+	mem->bus.io_reserved_vm = false;
+	list_del_init(&bo->io_reserve_lru);
+	ttm_mem_io_free(bo->bdev, mem);
 }
 
-static int ttm_mem_reg_ioremap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
-			void **virtual)
+static int ttm_mem_reg_ioremap(struct ttm_bo_device *bdev,
+			       struct ttm_mem_reg *mem,
+			       void **virtual)
 {
 	struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
 	int ret;
@@ -216,9 +210,11 @@ static int ttm_mem_reg_ioremap(struct ttm_bo_device *bdev, struct ttm_mem_reg *m
 		addr = mem->bus.addr;
 	} else {
 		if (mem->placement & TTM_PL_FLAG_WC)
-			addr = ioremap_wc(mem->bus.base + mem->bus.offset, mem->bus.size);
+			addr = ioremap_wc(mem->bus.base + mem->bus.offset,
+					  mem->bus.size);
 		else
-			addr = ioremap(mem->bus.base + mem->bus.offset, mem->bus.size);
+			addr = ioremap(mem->bus.base + mem->bus.offset,
+				       mem->bus.size);
 		if (!addr) {
 			(void) ttm_mem_io_lock(man, false);
 			ttm_mem_io_free(bdev, mem);
@@ -230,8 +226,9 @@ static int ttm_mem_reg_ioremap(struct ttm_bo_device *bdev, struct ttm_mem_reg *m
 	return 0;
 }
 
-static void ttm_mem_reg_iounmap(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem,
-			 void *virtual)
+static void ttm_mem_reg_iounmap(struct ttm_bo_device *bdev,
+				struct ttm_mem_reg *mem,
+				void *virtual)
 {
 	struct ttm_mem_type_manager *man;
 
@@ -513,11 +510,13 @@ static int ttm_bo_ioremap(struct ttm_buffer_object *bo,
 	} else {
 		map->bo_kmap_type = ttm_bo_map_iomap;
 		if (mem->placement & TTM_PL_FLAG_WC)
-			map->virtual = ioremap_wc(bo->mem.bus.base + bo->mem.bus.offset + offset,
+			map->virtual = ioremap_wc(bo->mem.bus.base +
+						  bo->mem.bus.offset + offset,
 						  size);
 		else
-			map->virtual = ioremap(bo->mem.bus.base + bo->mem.bus.offset + offset,
-						       size);
+			map->virtual = ioremap(bo->mem.bus.base +
+					       bo->mem.bus.offset + offset,
+					       size);
 	}
 	return (!map->virtual) ? -ENOMEM : 0;
 }