[PATCH] drm/ttm: optimize errors checking and free _manager when finishing

[Xiongwei Song]

In the function ttm_page_alloc_init, kzalloc call is made for variable
_manager, we need to check its return value, it may return NULL.

In the function ttm_page_alloc_fini, we need to call kfree for variable
_manager, instead of make _manager NULL directly.

Signed-off-by: Xiongwei Song <sxwj...@gmail.com>
---
 drivers/gpu/drm/ttm/ttm_page_alloc.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c 
b/drivers/gpu/drm/ttm/ttm_page_alloc.c
index b5ba6441489f..e20a0b8e352b 100644
--- a/drivers/gpu/drm/ttm/ttm_page_alloc.c
+++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c
@@ -1007,6 +1007,10 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, 
unsigned max_pages)
        pr_info("Initializing pool allocator\n");
 
        _manager = kzalloc(sizeof(*_manager), GFP_KERNEL);
+       if (!_manager) {
+               ret = -ENOMEM;
+               goto out;
+       }
 
        ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc", 0);
 
@@ -1034,13 +1038,17 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, 
unsigned max_pages)
                                   &glob->kobj, "pool");
        if (unlikely(ret != 0)) {
                kobject_put(&_manager->kobj);
-               _manager = NULL;
-               return ret;
+               goto out_free_mgr;
        }
 
        ttm_pool_mm_shrink_init(_manager);
 
        return 0;
+out_free_mgr:
+       kfree(_manager);
+       _manager = NULL;
+out:
+       return ret;
 }
 
 void ttm_page_alloc_fini(void)
@@ -1055,6 +1063,7 @@ void ttm_page_alloc_fini(void)
                ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES, true);
 
        kobject_put(&_manager->kobj);
+       kfree(_manager);
        _manager = NULL;
 }
 
-- 
2.15.1