1 files changed, 273 insertions, 260 deletions

diff --git a/mm/dmapool.c b/mm/dmapool.c
index c69781e97cf9..5d8af6e29127 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * DMA Pool allocator
  *
@@ -5,10 +6,6 @@
  * Copyright 2007 Intel Corporation
  *   Author: Matthew Wilcox <willy@linux.intel.com>
  *
- * This software may be redistributed and/or modified under the terms of
- * the GNU General Public License ("GPL") version 2 as published by the
- * Free Software Foundation.
- *
  * This allocator returns small blocks of a given size which are DMA-able by
  * the given device.  It uses the dma_alloc_coherent page allocator to get
  * new pages, then splits them up into blocks of the required size.
@@ -18,7 +15,7 @@
  * represented by the 'struct dma_pool' which keeps a doubly-linked list of
  * allocated pages.  Each page in the page_list is split into blocks of at
  * least 'size' bytes.  Free blocks are tracked in an unsorted singly-linked
- * list of free blocks within the page.  Used blocks aren't tracked, but we
+ * list of free blocks across all pages.  Used blocks aren't tracked, but we
  * keep a count of how many are currently allocated from each page.
  */
 
@@ -31,6 +28,7 @@
 #include <linux/mutex.h>
 #include <linux/poison.h>
 #include <linux/sched.h>
+#include <linux/sched/mm.h>
 #include <linux/slab.h>
 #include <linux/stat.h>
 #include <linux/spinlock.h>
@@ -38,17 +36,27 @@
 #include <linux/types.h>
 #include <linux/wait.h>
 
-#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB_DEBUG_ON)
+#ifdef CONFIG_SLUB_DEBUG_ON
 #define DMAPOOL_DEBUG 1
 #endif
 
+struct dma_block {
+	struct dma_block *next_block;
+	dma_addr_t dma;
+};
+
 struct dma_pool {		/* the pool */
 	struct list_head page_list;
 	spinlock_t lock;
-	size_t size;
+	struct dma_block *next_block;
+	size_t nr_blocks;
+	size_t nr_active;
+	size_t nr_pages;
 	struct device *dev;
-	size_t allocation;
-	size_t boundary;
+	unsigned int size;
+	unsigned int allocation;
+	unsigned int boundary;
+	int node;
 	char name[32];
 	struct list_head pools;
 };
@@ -57,67 +65,152 @@ struct dma_page {		/* cacheable header for 'allocation' bytes */
 	struct list_head page_list;
 	void *vaddr;
 	dma_addr_t dma;
-	unsigned int in_use;
-	unsigned int offset;
 };
 
 static DEFINE_MUTEX(pools_lock);
+static DEFINE_MUTEX(pools_reg_lock);
 
-static ssize_t
-show_pools(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t pools_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	unsigned temp;
-	unsigned size;
-	char *next;
-	struct dma_page *page;
 	struct dma_pool *pool;
+	unsigned size;
 
-	next = buf;
-	size = PAGE_SIZE;
-
-	temp = scnprintf(next, size, "poolinfo - 0.1\n");
-	size -= temp;
-	next += temp;
+	size = sysfs_emit(buf, "poolinfo - 0.1\n");
 
 	mutex_lock(&pools_lock);
 	list_for_each_entry(pool, &dev->dma_pools, pools) {
-		unsigned pages = 0;
-		unsigned blocks = 0;
+		/* per-pool info, no real statistics yet */
+		size += sysfs_emit_at(buf, size, "%-16s %4zu %4zu %4u %2zu\n",
+				      pool->name, pool->nr_active,
+				      pool->nr_blocks, pool->size,
+				      pool->nr_pages);
+	}
+	mutex_unlock(&pools_lock);
+
+	return size;
+}
+
+static DEVICE_ATTR_RO(pools);
+
+#ifdef DMAPOOL_DEBUG
+static void pool_check_block(struct dma_pool *pool, struct dma_block *block,
+			     gfp_t mem_flags)
+{
+	u8 *data = (void *)block;
+	int i;
+
+	for (i = sizeof(struct dma_block); i < pool->size; i++) {
+		if (data[i] == POOL_POISON_FREED)
+			continue;
+		dev_err(pool->dev, "%s %s, %p (corrupted)\n", __func__,
+			pool->name, block);
+
+		/*
+		 * Dump the first 4 bytes even if they are not
+		 * POOL_POISON_FREED
+		 */
+		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1,
+				data, pool->size, 1);
+		break;
+	}
+
+	if (!want_init_on_alloc(mem_flags))
+		memset(block, POOL_POISON_ALLOCATED, pool->size);
+}
+
+static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma)
+{
+	struct dma_page *page;
+
+	list_for_each_entry(page, &pool->page_list, page_list) {
+		if (dma < page->dma)
+			continue;
+		if ((dma - page->dma) < pool->allocation)
+			return page;
+	}
+	return NULL;
+}
+
+static bool pool_block_err(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
+{
+	struct dma_block *block = pool->next_block;
+	struct dma_page *page;
+
+	page = pool_find_page(pool, dma);
+	if (!page) {
+		dev_err(pool->dev, "%s %s, %p/%pad (bad dma)\n",
+			__func__, pool->name, vaddr, &dma);
+		return true;
+	}
 
-		spin_lock_irq(&pool->lock);
-		list_for_each_entry(page, &pool->page_list, page_list) {
-			pages++;
-			blocks += page->in_use;
+	while (block) {
+		if (block != vaddr) {
+			block = block->next_block;
+			continue;
 		}
-		spin_unlock_irq(&pool->lock);
+		dev_err(pool->dev, "%s %s, dma %pad already free\n",
+			__func__, pool->name, &dma);
+		return true;
+	}
 
-		/* per-pool info, no real statistics yet */
-		temp = scnprintf(next, size, "%-16s %4u %4Zu %4Zu %2u\n",
-				 pool->name, blocks,
-				 pages * (pool->allocation / pool->size),
-				 pool->size, pages);
-		size -= temp;
-		next += temp;
+	memset(vaddr, POOL_POISON_FREED, pool->size);
+	return false;
+}
+
+static void pool_init_page(struct dma_pool *pool, struct dma_page *page)
+{
+	memset(page->vaddr, POOL_POISON_FREED, pool->allocation);
+}
+#else
+static void pool_check_block(struct dma_pool *pool, struct dma_block *block,
+			     gfp_t mem_flags)
+{
+}
+
+static bool pool_block_err(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
+{
+	if (want_init_on_free())
+		memset(vaddr, 0, pool->size);
+	return false;
+}
+
+static void pool_init_page(struct dma_pool *pool, struct dma_page *page)
+{
+}
+#endif
+
+static struct dma_block *pool_block_pop(struct dma_pool *pool)
+{
+	struct dma_block *block = pool->next_block;
+
+	if (block) {
+		pool->next_block = block->next_block;
+		pool->nr_active++;
 	}
-	mutex_unlock(&pools_lock);
+	return block;
+}
 
-	return PAGE_SIZE - size;
+static void pool_block_push(struct dma_pool *pool, struct dma_block *block,
+			    dma_addr_t dma)
+{
+	block->dma = dma;
+	block->next_block = pool->next_block;
+	pool->next_block = block;
 }
 
-static DEVICE_ATTR(pools, S_IRUGO, show_pools, NULL);
 
 /**
- * dma_pool_create - Creates a pool of consistent memory blocks, for dma.
+ * dma_pool_create_node - Creates a pool of coherent DMA memory blocks.
  * @name: name of pool, for diagnostics
  * @dev: device that will be doing the DMA
  * @size: size of the blocks in this pool.
  * @align: alignment requirement for blocks; must be a power of two
  * @boundary: returned blocks won't cross this power of two boundary
- * Context: !in_interrupt()
+ * @node: optional NUMA node to allocate structs 'dma_pool' and 'dma_page' on
+ * Context: not in_interrupt()
  *
- * Returns a dma allocation pool with the requested characteristics, or
- * null if one can't be created.  Given one of these pools, dma_pool_alloc()
- * may be used to allocate memory.  Such memory will all have "consistent"
+ * Given one of these pools, dma_pool_alloc()
+ * may be used to allocate memory.  Such memory will all have coherent
  * DMA mappings, accessible by the device and its driver without using
  * cache flushing primitives.  The actual size of blocks allocated may be
  * larger than requested because of alignment.
@@ -126,41 +219,45 @@ static DEVICE_ATTR(pools, S_IRUGO, show_pools, NULL);
  * cross that size boundary.  This is useful for devices which have
  * addressing restrictions on individual DMA transfers, such as not crossing
  * boundaries of 4KBytes.
+ *
+ * Return: a dma allocation pool with the requested characteristics, or
+ * %NULL if one can't be created.
  */
-struct dma_pool *dma_pool_create(const char *name, struct device *dev,
-				 size_t size, size_t align, size_t boundary)
+struct dma_pool *dma_pool_create_node(const char *name, struct device *dev,
+		size_t size, size_t align, size_t boundary, int node)
 {
 	struct dma_pool *retval;
 	size_t allocation;
+	bool empty;
 
-	if (align == 0) {
-		align = 1;
-	} else if (align & (align - 1)) {
+	if (!dev)
 		return NULL;
-	}
 
-	if (size == 0) {
+	if (align == 0)
+		align = 1;
+	else if (align & (align - 1))
 		return NULL;
-	} else if (size < 4) {
-		size = 4;
-	}
 
-	if ((size % align) != 0)
-		size = ALIGN(size, align);
+	if (size == 0 || size > INT_MAX)
+		return NULL;
+	if (size < sizeof(struct dma_block))
+		size = sizeof(struct dma_block);
 
+	size = ALIGN(size, align);
 	allocation = max_t(size_t, size, PAGE_SIZE);
 
-	if (!boundary) {
+	if (!boundary)
 		boundary = allocation;
-	} else if ((boundary < size) || (boundary & (boundary - 1))) {
+	else if ((boundary < size) || (boundary & (boundary - 1)))
 		return NULL;
-	}
 
-	retval = kmalloc_node(sizeof(*retval), GFP_KERNEL, dev_to_node(dev));
+	boundary = min(boundary, allocation);
+
+	retval = kzalloc_node(sizeof(*retval), GFP_KERNEL, node);
 	if (!retval)
 		return retval;
 
-	strlcpy(retval->name, name, sizeof(retval->name));
+	strscpy(retval->name, name, sizeof(retval->name));
 
 	retval->dev = dev;
 
@@ -169,84 +266,90 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev,
 	retval->size = size;
 	retval->boundary = boundary;
 	retval->allocation = allocation;
+	retval->node = node;
+	INIT_LIST_HEAD(&retval->pools);
 
-	if (dev) {
-		int ret;
-
-		mutex_lock(&pools_lock);
-		if (list_empty(&dev->dma_pools))
-			ret = device_create_file(dev, &dev_attr_pools);
-		else
-			ret = 0;
-		/* note:  not currently insisting "name" be unique */
-		if (!ret)
-			list_add(&retval->pools, &dev->dma_pools);
-		else {
+	/*
+	 * pools_lock ensures that the ->dma_pools list does not get corrupted.
+	 * pools_reg_lock ensures that there is not a race between
+	 * dma_pool_create() and dma_pool_destroy() or within dma_pool_create()
+	 * when the first invocation of dma_pool_create() failed on
+	 * device_create_file() and the second assumes that it has been done (I
+	 * know it is a short window).
+	 */
+	mutex_lock(&pools_reg_lock);
+	mutex_lock(&pools_lock);
+	empty = list_empty(&dev->dma_pools);
+	list_add(&retval->pools, &dev->dma_pools);
+	mutex_unlock(&pools_lock);
+	if (empty) {
+		int err;
+
+		err = device_create_file(dev, &dev_attr_pools);
+		if (err) {
+			mutex_lock(&pools_lock);
+			list_del(&retval->pools);
+			mutex_unlock(&pools_lock);
+			mutex_unlock(&pools_reg_lock);
 			kfree(retval);
-			retval = NULL;
+			return NULL;
 		}
-		mutex_unlock(&pools_lock);
-	} else
-		INIT_LIST_HEAD(&retval->pools);
-
+	}
+	mutex_unlock(&pools_reg_lock);
 	return retval;
 }
-EXPORT_SYMBOL(dma_pool_create);
+EXPORT_SYMBOL(dma_pool_create_node);
 
 static void pool_initialise_page(struct dma_pool *pool, struct dma_page *page)
 {
-	unsigned int offset = 0;
-	unsigned int next_boundary = pool->boundary;
+	unsigned int next_boundary = pool->boundary, offset = 0;
+	struct dma_block *block, *first = NULL, *last = NULL;
 
-	do {
-		unsigned int next = offset + pool->size;
-		if (unlikely((next + pool->size) >= next_boundary)) {
-			next = next_boundary;
+	pool_init_page(pool, page);
+	while (offset + pool->size <= pool->allocation) {
+		if (offset + pool->size > next_boundary) {
+			offset = next_boundary;
 			next_boundary += pool->boundary;
+			continue;
 		}
-		*(int *)(page->vaddr + offset) = next;
-		offset = next;
-	} while (offset < pool->allocation);
+
+		block = page->vaddr + offset;
+		block->dma = page->dma + offset;
+		block->next_block = NULL;
+
+		if (last)
+			last->next_block = block;
+		else
+			first = block;
+		last = block;
+
+		offset += pool->size;
+		pool->nr_blocks++;
+	}
+
+	last->next_block = pool->next_block;
+	pool->next_block = first;
+
+	list_add(&page->page_list, &pool->page_list);
+	pool->nr_pages++;
 }
 
 static struct dma_page *pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags)
 {
 	struct dma_page *page;
 
-	page = kmalloc(sizeof(*page), mem_flags);
+	page = kmalloc_node(sizeof(*page), mem_flags, pool->node);
 	if (!page)
 		return NULL;
+
 	page->vaddr = dma_alloc_coherent(pool->dev, pool->allocation,
 					 &page->dma, mem_flags);
-	if (page->vaddr) {
-#ifdef	DMAPOOL_DEBUG
-		memset(page->vaddr, POOL_POISON_FREED, pool->allocation);
-#endif
-		pool_initialise_page(pool, page);
-		page->in_use = 0;
-		page->offset = 0;
-	} else {
+	if (!page->vaddr) {
 		kfree(page);
-		page = NULL;
+		return NULL;
 	}
-	return page;
-}
-
-static inline int 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);
+	return page;
 }
 
 /**
@@ -259,30 +362,32 @@ static void pool_free_page(struct dma_pool *pool, struct dma_page *page)
  */
 void dma_pool_destroy(struct dma_pool *pool)
 {
+	struct dma_page *page, *tmp;
+	bool empty, busy = false;
+
+	if (unlikely(!pool))
+		return;
+
+	mutex_lock(&pools_reg_lock);
 	mutex_lock(&pools_lock);
 	list_del(&pool->pools);
-	if (pool->dev && list_empty(&pool->dev->dma_pools))
-		device_remove_file(pool->dev, &dev_attr_pools);
+	empty = list_empty(&pool->dev->dma_pools);
 	mutex_unlock(&pools_lock);
+	if (empty)
+		device_remove_file(pool->dev, &dev_attr_pools);
+	mutex_unlock(&pools_reg_lock);
+
+	if (pool->nr_active) {
+		dev_err(pool->dev, "%s %s busy\n", __func__, pool->name);
+		busy = true;
+	}
 
-	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)) {
-			if (pool->dev)
-				dev_err(pool->dev,
-					"dma_pool_destroy %s, %p busy\n",
-					pool->name, page->vaddr);
-			else
-				printk(KERN_ERR
-				       "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);
+	list_for_each_entry_safe(page, tmp, &pool->page_list, page_list) {
+		if (!busy)
+			dma_free_coherent(pool->dev, pool->allocation,
+					  page->vaddr, page->dma);
+		list_del(&page->page_list);
+		kfree(page);
 	}
 
 	kfree(pool);
@@ -290,91 +395,51 @@ void dma_pool_destroy(struct dma_pool *pool)
 EXPORT_SYMBOL(dma_pool_destroy);
 
 /**
- * dma_pool_alloc - get a block of consistent memory
+ * dma_pool_alloc - get a block of coherent memory
  * @pool: dma pool that will produce the block
  * @mem_flags: GFP_* bitmask
  * @handle: pointer to dma address of block
  *
- * This returns the kernel virtual address of a currently unused block,
+ * Return: the kernel virtual address of a currently unused block,
  * and reports its dma address through the handle.
  * If such a memory block can't be allocated, %NULL is returned.
  */
 void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
 		     dma_addr_t *handle)
 {
-	unsigned long flags;
+	struct dma_block *block;
 	struct dma_page *page;
-	size_t offset;
-	void *retval;
+	unsigned long flags;
 
-	might_sleep_if(mem_flags & __GFP_WAIT);
+	might_alloc(mem_flags);
 
 	spin_lock_irqsave(&pool->lock, flags);
-	list_for_each_entry(page, &pool->page_list, page_list) {
-		if (page->offset < pool->allocation)
-			goto ready;
-	}
-
-	/* pool_alloc_page() might sleep, so temporarily drop &pool->lock */
-	spin_unlock_irqrestore(&pool->lock, flags);
-
-	page = pool_alloc_page(pool, mem_flags);
-	if (!page)
-		return NULL;
+	block = pool_block_pop(pool);
+	if (!block) {
+		/*
+		 * pool_alloc_page() might sleep, so temporarily drop
+		 * &pool->lock
+		 */
+		spin_unlock_irqrestore(&pool->lock, flags);
 
-	spin_lock_irqsave(&pool->lock, flags);
+		page = pool_alloc_page(pool, mem_flags & (~__GFP_ZERO));
+		if (!page)
+			return NULL;
 
-	list_add(&page->page_list, &pool->page_list);
- ready:
-	page->in_use++;
-	offset = page->offset;
-	page->offset = *(int *)(page->vaddr + offset);
-	retval = offset + page->vaddr;
-	*handle = offset + page->dma;
-#ifdef	DMAPOOL_DEBUG
-	{
-		int i;
-		u8 *data = retval;
-		/* page->offset is stored in first 4 bytes */
-		for (i = sizeof(page->offset); i < pool->size; i++) {
-			if (data[i] == POOL_POISON_FREED)
-				continue;
-			if (pool->dev)
-				dev_err(pool->dev,
-					"dma_pool_alloc %s, %p (corruped)\n",
-					pool->name, retval);
-			else
-				pr_err("dma_pool_alloc %s, %p (corruped)\n",
-					pool->name, retval);
-
-			/*
-			 * Dump the first 4 bytes even if they are not
-			 * POOL_POISON_FREED
-			 */
-			print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1,
-					data, pool->size, 1);
-			break;
-		}
+		spin_lock_irqsave(&pool->lock, flags);
+		pool_initialise_page(pool, page);
+		block = pool_block_pop(pool);
 	}
-	memset(retval, POOL_POISON_ALLOCATED, pool->size);
-#endif
 	spin_unlock_irqrestore(&pool->lock, flags);
-	return retval;
-}
-EXPORT_SYMBOL(dma_pool_alloc);
 
-static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma)
-{
-	struct dma_page *page;
+	*handle = block->dma;
+	pool_check_block(pool, block, mem_flags);
+	if (want_init_on_alloc(mem_flags))
+		memset(block, 0, pool->size);
 
-	list_for_each_entry(page, &pool->page_list, page_list) {
-		if (dma < page->dma)
-			continue;
-		if (dma < (page->dma + pool->allocation))
-			return page;
-	}
-	return NULL;
+	return block;
 }
+EXPORT_SYMBOL(dma_pool_alloc);
 
 /**
  * dma_pool_free - put block back into dma pool
@@ -387,68 +452,14 @@ static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma)
  */
 void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
 {
-	struct dma_page *page;
+	struct dma_block *block = vaddr;
 	unsigned long flags;
-	unsigned int offset;
 
 	spin_lock_irqsave(&pool->lock, flags);
-	page = pool_find_page(pool, dma);
-	if (!page) {
-		spin_unlock_irqrestore(&pool->lock, flags);
-		if (pool->dev)
-			dev_err(pool->dev,
-				"dma_pool_free %s, %p/%lx (bad dma)\n",
-				pool->name, vaddr, (unsigned long)dma);
-		else
-			printk(KERN_ERR "dma_pool_free %s, %p/%lx (bad dma)\n",
-			       pool->name, vaddr, (unsigned long)dma);
-		return;
-	}
-
-	offset = vaddr - page->vaddr;
-#ifdef	DMAPOOL_DEBUG
-	if ((dma - page->dma) != offset) {
-		spin_unlock_irqrestore(&pool->lock, flags);
-		if (pool->dev)
-			dev_err(pool->dev,
-				"dma_pool_free %s, %p (bad vaddr)/%Lx\n",
-				pool->name, vaddr, (unsigned long long)dma);
-		else
-			printk(KERN_ERR
-			       "dma_pool_free %s, %p (bad vaddr)/%Lx\n",
-			       pool->name, vaddr, (unsigned long long)dma);
-		return;
-	}
-	{
-		unsigned int chain = page->offset;
-		while (chain < pool->allocation) {
-			if (chain != offset) {
-				chain = *(int *)(page->vaddr + chain);
-				continue;
-			}
-			spin_unlock_irqrestore(&pool->lock, flags);
-			if (pool->dev)
-				dev_err(pool->dev, "dma_pool_free %s, dma %Lx "
-					"already free\n", pool->name,
-					(unsigned long long)dma);
-			else
-				printk(KERN_ERR "dma_pool_free %s, dma %Lx "
-					"already free\n", pool->name,
-					(unsigned long long)dma);
-			return;
-		}
+	if (!pool_block_err(pool, vaddr, dma)) {
+		pool_block_push(pool, block, dma);
+		pool->nr_active--;
 	}
-	memset(vaddr, POOL_POISON_FREED, pool->size);
-#endif
-
-	page->in_use--;
-	*(int *)vaddr = page->offset;
-	page->offset = offset;
-	/*
-	 * Resist a temptation to do
-	 *    if (!is_page_busy(page)) pool_free_page(pool, page);
-	 * Better have a few empty pages hang around.
-	 */
 	spin_unlock_irqrestore(&pool->lock, flags);
 }
 EXPORT_SYMBOL(dma_pool_free);
@@ -478,6 +489,9 @@ static int dmam_pool_match(struct device *dev, void *res, void *match_data)
  *
  * Managed dma_pool_create().  DMA pool created with this function is
  * automatically destroyed on driver detach.
+ *
+ * Return: a managed dma allocation pool with the requested
+ * characteristics, or %NULL if one can't be created.
  */
 struct dma_pool *dmam_pool_create(const char *name, struct device *dev,
 				  size_t size, size_t align, size_t allocation)
@@ -508,7 +522,6 @@ void dmam_pool_destroy(struct dma_pool *pool)
 {
 	struct device *dev = pool->dev;
 
-	WARN_ON(devres_destroy(dev, dmam_pool_release, dmam_pool_match, pool));
-	dma_pool_destroy(pool);
+	WARN_ON(devres_release(dev, dmam_pool_release, dmam_pool_match, pool));
 }
 EXPORT_SYMBOL(dmam_pool_destroy);