Merge branch 'dmapool' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc

			   cpu.o firmware.o init.o map.o devres.o \

			   attribute_container.o transport_class.o

obj-y			+= power/

obj-$(CONFIG_HAS_DMA)	+= dma-mapping.o dmapool.o

obj-$(CONFIG_HAS_DMA)	+= dma-mapping.o

obj-$(CONFIG_ISA)	+= isa.o

obj-$(CONFIG_FW_LOADER)	+= firmware_class.o

obj-$(CONFIG_NUMA)	+= node.o

obj-$(CONFIG_PROC_PAGE_MONITOR) += pagewalk.o

obj-$(CONFIG_BOUNCE)	+= bounce.o

obj-$(CONFIG_SWAP)	+= page_io.o swap_state.o swapfile.o thrash.o

obj-$(CONFIG_HAS_DMA)	+= dmapool.o

obj-$(CONFIG_HUGETLBFS)	+= hugetlb.o

obj-$(CONFIG_NUMA) 	+= mempolicy.o

obj-$(CONFIG_SPARSEMEM)	+= sparse.o

/*

 * DMA Pool allocator

 *

 * Copyright 2001 David Brownell

 * 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.

 * Many older drivers still have their own code to do this.

 *

 * The current design of this allocator is fairly simple.  The pool is

 * 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

 * keep a count of how many are currently allocated from each page.

 */

#include <linux/device.h>

#include <linux/mm.h>

#include <asm/io.h>		/* Needed for i386 to build */

#include <linux/dma-mapping.h>

#include <linux/dmapool.h>

#include <linux/slab.h>

#include <linux/kernel.h>

#include <linux/list.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/poison.h>

#include <linux/sched.h>

/*

 * Pool allocator ... wraps the dma_alloc_coherent page allocator, so

 * small blocks are easily used by drivers for bus mastering controllers.

 * This should probably be sharing the guts of the slab allocator.

 */

#include <linux/slab.h>

#include <linux/spinlock.h>

#include <linux/string.h>

#include <linux/types.h>

#include <linux/wait.h>

struct dma_pool {		/* the pool */

	struct list_head page_list;

	spinlock_t lock;

	size_t			blocks_per_page;

	size_t size;

	struct device *dev;

	size_t allocation;

	size_t boundary;

	char name[32];

	wait_queue_head_t waitq;

	struct list_head pools;

	struct list_head page_list;

	void *vaddr;

	dma_addr_t dma;

	unsigned		in_use;

	unsigned long		bitmap [0];

	unsigned int in_use;

	unsigned int offset;

};

#define	POOL_TIMEOUT_JIFFIES	((100 /* msec */ * HZ) / 1000)

		/* per-pool info, no real statistics yet */

		temp = scnprintf(next, size, "%-16s %4u %4Zu %4Zu %2u\n",

				pool->name,

				blocks, pages * pool->blocks_per_page,

				 pool->name, blocks,

				 pages * (pool->allocation / pool->size),

				 pool->size, pages);

		size -= temp;

		next += temp;

	return PAGE_SIZE - size;

}

static DEVICE_ATTR(pools, S_IRUGO, show_pools, NULL);

/**

 * @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

 * @allocation: returned blocks won't cross this boundary (or zero)

 * @boundary: returned blocks won't cross this power of two boundary

 * Context: !in_interrupt()

 *

 * Returns a dma allocation pool with the requested characteristics, or

 * cache flushing primitives.  The actual size of blocks allocated may be

 * larger than requested because of alignment.

 *

 * If allocation is nonzero, objects returned from dma_pool_alloc() won't

 * If @boundary is nonzero, objects returned from dma_pool_alloc() won't

 * cross that size boundary.  This is useful for devices which have

 * addressing restrictions on individual DMA transfers, such as not crossing

 * boundaries of 4KBytes.

 */

struct dma_pool *

dma_pool_create (const char *name, struct device *dev,

	size_t size, size_t align, size_t allocation)

struct dma_pool *dma_pool_create(const char *name, struct device *dev,

				 size_t size, size_t align, size_t boundary)

{

	struct dma_pool *retval;

	size_t allocation;

	if (align == 0)

	if (align == 0) {

		align = 1;

	if (size == 0)

	} else if (align & (align - 1)) {

		return NULL;

	else if (size < align)

		size = align;

	else if ((size % align) != 0) {

		size += align + 1;

		size &= ~(align - 1);

	}

	if (allocation == 0) {

		if (PAGE_SIZE < size)

			allocation = size;

		else

			allocation = PAGE_SIZE;

		// FIXME: round up for less fragmentation

	} else if (allocation < size)

	if (size == 0) {

		return NULL;

	} else if (size < 4) {

		size = 4;

	}

	if ((size % align) != 0)

		size = ALIGN(size, align);

	if (!(retval = kmalloc_node (sizeof *retval, GFP_KERNEL, dev_to_node(dev))))

	allocation = max_t(size_t, size, PAGE_SIZE);

	if (!boundary) {

		boundary = allocation;

	} else if ((boundary < size) || (boundary & (boundary - 1))) {

		return NULL;

	}

	retval = kmalloc_node(sizeof(*retval), GFP_KERNEL, dev_to_node(dev));

	if (!retval)

		return retval;

	strlcpy (retval->name, name, sizeof retval->name);

	strlcpy(retval->name, name, sizeof(retval->name));

	retval->dev = dev;

	INIT_LIST_HEAD(&retval->page_list);

	spin_lock_init(&retval->lock);

	retval->size = size;

	retval->boundary = boundary;

	retval->allocation = allocation;

	retval->blocks_per_page = allocation / size;

	init_waitqueue_head(&retval->waitq);

	if (dev) {

	return retval;

}

EXPORT_SYMBOL(dma_pool_create);

static void pool_initialise_page(struct dma_pool *pool, struct dma_page *page)

{

	unsigned int offset = 0;

	unsigned int next_boundary = pool->boundary;

	do {

		unsigned int next = offset + pool->size;

		if (unlikely((next + pool->size) >= next_boundary)) {

			next = next_boundary;

			next_boundary += pool->boundary;

		}

		*(int *)(page->vaddr + offset) = next;

		offset = next;

	} while (offset < pool->allocation);

}

static struct dma_page *

pool_alloc_page (struct dma_pool *pool, gfp_t mem_flags)

static struct dma_page *pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags)

{

	struct dma_page *page;

	int		mapsize;

	mapsize = pool->blocks_per_page;

	mapsize = (mapsize + BITS_PER_LONG - 1) / BITS_PER_LONG;

	mapsize *= sizeof (long);

	page = kmalloc(mapsize + sizeof *page, mem_flags);

	page = kmalloc(sizeof(*page), mem_flags);

	if (!page)

		return NULL;

	page->vaddr = dma_alloc_coherent (pool->dev,

					    pool->allocation,

					    &page->dma,

					    mem_flags);

	page->vaddr = dma_alloc_coherent(pool->dev, pool->allocation,

					 &page->dma, mem_flags);

	if (page->vaddr) {

		memset (page->bitmap, 0xff, mapsize);	// bit set == free

#ifdef	CONFIG_DEBUG_SLAB

		memset(page->vaddr, POOL_POISON_FREED, pool->allocation);

#endif

		pool_initialise_page(pool, page);

		list_add(&page->page_list, &pool->page_list);

		page->in_use = 0;

		page->offset = 0;

	} else {

		kfree(page);

		page = NULL;

	return page;

}

static inline int

is_page_busy (int blocks, unsigned long *bitmap)

static inline int is_page_busy(struct dma_page *page)

{

	while (blocks > 0) {

		if (*bitmap++ != ~0UL)

			return 1;

		blocks -= BITS_PER_LONG;

	}

	return 0;

	return page->in_use != 0;

}

static void

pool_free_page (struct dma_pool *pool, struct dma_page *page)

static void pool_free_page(struct dma_pool *pool, struct dma_page *page)

{

	dma_addr_t dma = page->dma;

	kfree(page);

}

/**

 * dma_pool_destroy - destroys a pool of dma memory blocks.

 * @pool: dma pool that will be destroyed

 * Caller guarantees that no more memory from the pool is in use,

 * and that nothing will try to use the pool after this call.

 */

void

dma_pool_destroy (struct dma_pool *pool)

void dma_pool_destroy(struct dma_pool *pool)

{

	mutex_lock(&pools_lock);

	list_del(&pool->pools);

		struct dma_page *page;

		page = list_entry(pool->page_list.next,

				  struct dma_page, page_list);

		if (is_page_busy (pool->blocks_per_page, page->bitmap)) {

		if (is_page_busy(page)) {

			if (pool->dev)

				dev_err(pool->dev, "dma_pool_destroy %s, %p busy\n",

				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",

				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(pool);

}

EXPORT_SYMBOL(dma_pool_destroy);

/**

 * dma_pool_alloc - get a block of consistent memory

 *

 * This returns 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.

 * 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)

void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,

		     dma_addr_t *handle)

{

	unsigned long flags;

	struct dma_page *page;

	int			map, block;

	size_t offset;

	void *retval;

restart:

	spin_lock_irqsave(&pool->lock, flags);

 restart:

	list_for_each_entry(page, &pool->page_list, page_list) {

		int		i;

		/* only cachable accesses here ... */

		for (map = 0, i = 0;

				i < pool->blocks_per_page;

				i += BITS_PER_LONG, map++) {

			if (page->bitmap [map] == 0)

				continue;

			block = ffz (~ page->bitmap [map]);

			if ((i + block) < pool->blocks_per_page) {

				clear_bit (block, &page->bitmap [map]);

				offset = (BITS_PER_LONG * map) + block;

				offset *= pool->size;

		if (page->offset < pool->allocation)

			goto ready;

	}

		}

	}

	if (!(page = pool_alloc_page (pool, GFP_ATOMIC))) {

	page = pool_alloc_page(pool, GFP_ATOMIC);

	if (!page) {

		if (mem_flags & __GFP_WAIT) {

			DECLARE_WAITQUEUE(wait, current);

			__set_current_state(TASK_INTERRUPTIBLE);

			add_wait_queue (&pool->waitq, &wait);

			__add_wait_queue(&pool->waitq, &wait);

			spin_unlock_irqrestore(&pool->lock, flags);

			schedule_timeout(POOL_TIMEOUT_JIFFIES);

			remove_wait_queue (&pool->waitq, &wait);

			spin_lock_irqsave(&pool->lock, flags);

			__remove_wait_queue(&pool->waitq, &wait);

			goto restart;

		}

		retval = NULL;

		goto done;

	}

	clear_bit (0, &page->bitmap [0]);

	offset = 0;

 ready:

	page->in_use++;

	offset = page->offset;

	page->offset = *(int *)(page->vaddr + offset);

	retval = offset + page->vaddr;

	*handle = offset + page->dma;

#ifdef	CONFIG_DEBUG_SLAB

	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)

static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma)

{

	unsigned long flags;

	struct dma_page *page;

	return page;

}

/**

 * dma_pool_free - put block back into dma pool

 * @pool: the dma pool holding the block

 * Caller promises neither device nor driver will again touch this block

 * unless it is first re-allocated.

 */

void

dma_pool_free (struct dma_pool *pool, void *vaddr, dma_addr_t dma)

void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma)

{

	struct dma_page *page;

	unsigned long flags;

	int			map, block;

	unsigned int offset;

	if ((page = pool_find_page(pool, dma)) == NULL) {

	page = pool_find_page(pool, dma);

	if (!page) {

		if (pool->dev)

			dev_err(pool->dev, "dma_pool_free %s, %p/%lx (bad dma)\n",

			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",

		return;

	}

	block = dma - page->dma;

	block /= pool->size;

	map = block / BITS_PER_LONG;

	block %= BITS_PER_LONG;

	offset = vaddr - page->vaddr;

#ifdef	CONFIG_DEBUG_SLAB

	if (((dma - page->dma) + (void *)page->vaddr) != vaddr) {

	if ((dma - page->dma) != offset) {

		if (pool->dev)

			dev_err(pool->dev, "dma_pool_free %s, %p (bad vaddr)/%Lx\n",

			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",

			printk(KERN_ERR

			       "dma_pool_free %s, %p (bad vaddr)/%Lx\n",

			       pool->name, vaddr, (unsigned long long)dma);

		return;

	}

	if (page->bitmap [map] & (1UL << block)) {

	{

		unsigned int chain = page->offset;

		while (chain < pool->allocation) {

			if (chain != offset) {

				chain = *(int *)(page->vaddr + chain);

				continue;

			}

			if (pool->dev)

			dev_err(pool->dev, "dma_pool_free %s, dma %Lx already free\n",

				pool->name, (unsigned long long)dma);

				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);

				printk(KERN_ERR "dma_pool_free %s, dma %Lx "

					"already free\n", pool->name,

					(unsigned long long)dma);

			return;

		}

	}

	memset(vaddr, POOL_POISON_FREED, pool->size);

#endif

	spin_lock_irqsave(&pool->lock, flags);

	page->in_use--;

	set_bit (block, &page->bitmap [map]);

	*(int *)vaddr = page->offset;

	page->offset = offset;

	if (waitqueue_active(&pool->waitq))

		wake_up (&pool->waitq);

		wake_up_locked(&pool->waitq);

	/*

	 * Resist a temptation to do

	 *    if (!is_page_busy(bpp, page->bitmap)) pool_free_page(pool, page);

	 *    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);

/*

 * Managed DMA pool

	return pool;

}

EXPORT_SYMBOL(dmam_pool_create);

/**

 * dmam_pool_destroy - Managed dma_pool_destroy()

	dma_pool_destroy(pool);

	WARN_ON(devres_destroy(dev, dmam_pool_release, dmam_pool_match, pool));

}

EXPORT_SYMBOL (dma_pool_create);

EXPORT_SYMBOL (dma_pool_destroy);

EXPORT_SYMBOL (dma_pool_alloc);

EXPORT_SYMBOL (dma_pool_free);

EXPORT_SYMBOL (dmam_pool_create);

EXPORT_SYMBOL(dmam_pool_destroy);