[PATCH v3 03/10] dmapool: cleanup dma_pool_destroy

[Tony Battersby]

Remove a small amount of code duplication between dma_pool_destroy() and
pool_free_page() in preparation for adding more code without having to
duplicate it.  No functional changes.

Signed-off-by: Tony Battersby <to...@cybernetics.com>
---

No changes since v2.

--- linux/mm/dmapool.c.orig     2018-08-02 09:59:15.000000000 -0400
+++ linux/mm/dmapool.c  2018-08-02 10:01:26.000000000 -0400
@@ -249,13 +249,22 @@ static inline bool is_page_busy(struct d
 
 static void pool_free_page(struct dma_pool *pool, struct dma_page *page)
 {
+       void *vaddr = page->vaddr;
        dma_addr_t dma = page->dma;
 
+       list_del(&page->page_list);
+
+       if (is_page_busy(page)) {
+               dev_err(pool->dev,
+                       "dma_pool_destroy %s, %p busy\n",
+                       pool->name, vaddr);
+               /* leak the still-in-use consistent memory */
+       } else {
 #ifdef DMAPOOL_DEBUG
-       memset(page->vaddr, POOL_POISON_FREED, pool->allocation);
+               memset(vaddr, POOL_POISON_FREED, pool->allocation);
 #endif
-       dma_free_coherent(pool->dev, pool->allocation, page->vaddr, dma);
-       list_del(&page->page_list);
+               dma_free_coherent(pool->dev, pool->allocation, vaddr, dma);
+       }
        kfree(page);
 }
 
@@ -269,6 +278,7 @@ static void pool_free_page(struct dma_po
  */
 void dma_pool_destroy(struct dma_pool *pool)
 {
+       struct dma_page *page;
        bool empty = false;
 
        if (unlikely(!pool))
@@ -284,19 +294,10 @@ void dma_pool_destroy(struct dma_pool *p
                device_remove_file(pool->dev, &dev_attr_pools);
        mutex_unlock(&pools_reg_lock);
 
-       while (!list_empty(&pool->page_list)) {
-               struct dma_page *page;
-               page = list_entry(pool->page_list.next,
-                                 struct dma_page, page_list);
-               if (is_page_busy(page)) {
-                       dev_err(pool->dev,
-                               "dma_pool_destroy %s, %p busy\n",
-                               pool->name, page->vaddr);
-                       /* leak the still-in-use consistent memory */
-                       list_del(&page->page_list);
-                       kfree(page);
-               } else
-                       pool_free_page(pool, page);
+       while ((page = list_first_entry_or_null(&pool->page_list,
+                                               struct dma_page,
+                                               page_list))) {
+               pool_free_page(pool, page);
        }
 
        kfree(pool);

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu