[PATCHv3,09/12] dmapool: simplify freeing
Commit Message
From: Keith Busch <kbusch@kernel.org>
The actions for busy and not busy are mostly the same, so combine these
and remove the unnecessary function. Also, the pool is about to be freed
so there's no need to poison the page data since we only check for
poison on alloc, which can't be done on a freed pool.
Signed-off-by: Keith Busch <kbusch@kernel.org>
---
mm/dmapool.c | 26 +++++++-------------------
1 file changed, 7 insertions(+), 19 deletions(-)
Comments
> - * DMA Pool allocator
> +* DMA Pool allocator
This got corrupted somehow.
> + if (!is_page_busy(page))
> + dma_free_coherent(pool->dev, pool->allocation,
> + page->vaddr, page->dma);
> + else
> dev_err(pool->dev, "%s %s, %p busy\n", __func__,
> pool->name, page->vaddr);
> + list_del(&page->page_list);
> + kfree(page);
I'm still not sure what the point of leaking the page in case it is
busy vs letting KASAN and friends actually catch it, but the pure
rearrangement is an improvement over the previous state, so:
Reviewed-by: Christoph Hellwig <hch@lst.de>
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * DMA Pool allocator
+* DMA Pool allocator
*
* Copyright 2001 David Brownell
* Copyright 2007 Intel Corporation
@@ -241,18 +241,6 @@ static inline bool is_page_busy(struct dma_page *page)
return page->in_use != 0;
}
-static void pool_free_page(struct dma_pool *pool, struct dma_page *page)
-{
- dma_addr_t dma = page->dma;
-
-#ifdef DMAPOOL_DEBUG
- memset(page->vaddr, POOL_POISON_FREED, pool->allocation);
-#endif
- dma_free_coherent(pool->dev, pool->allocation, page->vaddr, dma);
- list_del(&page->page_list);
- kfree(page);
-}
-
/**
* dma_pool_destroy - destroys a pool of dma memory blocks.
* @pool: dma pool that will be destroyed
@@ -280,14 +268,14 @@ void dma_pool_destroy(struct dma_pool *pool)
mutex_unlock(&pools_reg_lock);
list_for_each_entry_safe(page, tmp, &pool->page_list, page_list) {
- if (is_page_busy(page)) {
+ if (!is_page_busy(page))
+ dma_free_coherent(pool->dev, pool->allocation,
+ page->vaddr, page->dma);
+ else
dev_err(pool->dev, "%s %s, %p busy\n", __func__,
pool->name, page->vaddr);
- /* leak the still-in-use consistent memory */
- list_del(&page->page_list);
- kfree(page);
- } else
- pool_free_page(pool, page);
+ list_del(&page->page_list);
+ kfree(page);
}
kfree(pool);