[PATCH 2/3] Replace pci_pool with generic dma_pool

[Deepak Saxena <dsaxena@plexity.net>]

- Remove drivers/pci/pool.c
- Remove initialization of struct pci_dev.pools from pci_setup_device()


diff -Nru a/drivers/pci/Makefile b/drivers/pci/Makefile
--- a/drivers/pci/Makefile	Fri Jan 30 12:20:30 2004
+++ b/drivers/pci/Makefile	Fri Jan 30 12:20:30 2004
@@ -2,7 +2,7 @@
 # Makefile for the PCI bus specific drivers.
 #
 
-obj-y		+= access.o bus.o probe.o remove.o pci.o pool.o quirks.o \
+obj-y		+= access.o bus.o probe.o remove.o pci.o quirks.o \
 			names.o pci-driver.o search.o pci-sysfs.o
 obj-$(CONFIG_PROC_FS) += proc.o
 
diff -Nru a/drivers/pci/pool.c b/drivers/pci/pool.c
--- a/drivers/pci/pool.c	Fri Jan 30 12:20:30 2004
+++ /dev/null	Wed Dec 31 16:00:00 1969
@@ -1,404 +0,0 @@
-#include <linux/pci.h>
-#include <linux/slab.h>
-#include <linux/module.h>
-
-/*
- * Pool allocator ... wraps the pci_alloc_consistent 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.
- */
-
-struct pci_pool {	/* the pool */
-	struct list_head	page_list;
-	spinlock_t		lock;
-	size_t			blocks_per_page;
-	size_t			size;
-	struct pci_dev		*dev;
-	size_t			allocation;
-	char			name [32];
-	wait_queue_head_t	waitq;
-	struct list_head	pools;
-};
-
-struct pci_page {	/* cacheable header for 'allocation' bytes */
-	struct list_head	page_list;
-	void			*vaddr;
-	dma_addr_t		dma;
-	unsigned		in_use;
-	unsigned long		bitmap [0];
-};
-
-#define	POOL_TIMEOUT_JIFFIES	((100 /* msec */ * HZ) / 1000)
-#define	POOL_POISON_FREED	0xa7	/* !inuse */
-#define	POOL_POISON_ALLOCATED	0xa9	/* !initted */
-
-static DECLARE_MUTEX (pools_lock);
-
-static ssize_t
-show_pools (struct device *dev, char *buf)
-{
-	struct pci_dev		*pdev;
-	unsigned		temp, size;
-	char			*next;
-	struct list_head	*i, *j;
-
-	pdev = container_of (dev, struct pci_dev, dev);
-	next = buf;
-	size = PAGE_SIZE;
-
-	temp = snprintf (next, size, "poolinfo - 0.1\n");
-	size -= temp;
-	next += temp;
-
-	down (&pools_lock);
-	list_for_each (i, &pdev->pools) {
-		struct pci_pool	*pool;
-		unsigned	pages = 0, blocks = 0;
-
-		pool = list_entry (i, struct pci_pool, pools);
-
-		list_for_each (j, &pool->page_list) {
-			struct pci_page	*page;
-
-			page = list_entry (j, struct pci_page, page_list);
-			pages++;
-			blocks += page->in_use;
-		}
-
-		/* per-pool info, no real statistics yet */
-		temp = snprintf (next, size, "%-16s %4u %4Zu %4Zu %2u\n",
-				pool->name,
-				blocks, pages * pool->blocks_per_page,
-				pool->size, pages);
-		size -= temp;
-		next += temp;
-	}
-	up (&pools_lock);
-
-	return PAGE_SIZE - size;
-}
-static DEVICE_ATTR (pools, S_IRUGO, show_pools, NULL);
-
-/**
- * pci_pool_create - Creates a pool of pci consistent memory blocks, for dma.
- * @name: name of pool, for diagnostics
- * @pdev: pci 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)
- * Context: !in_interrupt()
- *
- * Returns a pci allocation pool with the requested characteristics, or
- * null if one can't be created.  Given one of these pools, pci_pool_alloc()
- * may be used to allocate memory.  Such memory will all have "consistent"
- * 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.
- *
- * If allocation is nonzero, objects returned from pci_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 pci_pool *
-pci_pool_create (const char *name, struct pci_dev *pdev,
-	size_t size, size_t align, size_t allocation)
-{
-	struct pci_pool		*retval;
-
-	if (align == 0)
-		align = 1;
-	if (size == 0)
-		return 0;
-	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)
-		return 0;
-
-	if (!(retval = kmalloc (sizeof *retval, SLAB_KERNEL)))
-		return retval;
-
-	strlcpy (retval->name, name, sizeof retval->name);
-
-	retval->dev = pdev;
-
-	INIT_LIST_HEAD (&retval->page_list);
-	spin_lock_init (&retval->lock);
-	retval->size = size;
-	retval->allocation = allocation;
-	retval->blocks_per_page = allocation / size;
-	init_waitqueue_head (&retval->waitq);
-
-	if (pdev) {
-		down (&pools_lock);
-		if (list_empty (&pdev->pools))
-			device_create_file (&pdev->dev, &dev_attr_pools);
-		/* note:  not currently insisting "name" be unique */
-		list_add (&retval->pools, &pdev->pools);
-		up (&pools_lock);
-	} else
-		INIT_LIST_HEAD (&retval->pools);
-
-	return retval;
-}
-
-
-static struct pci_page *
-pool_alloc_page (struct pci_pool *pool, int mem_flags)
-{
-	struct pci_page	*page;
-	int		mapsize;
-
-	mapsize = pool->blocks_per_page;
-	mapsize = (mapsize + BITS_PER_LONG - 1) / BITS_PER_LONG;
-	mapsize *= sizeof (long);
-
-	page = (struct pci_page *) kmalloc (mapsize + sizeof *page, mem_flags);
-	if (!page)
-		return 0;
-	page->vaddr = pci_alloc_consistent (pool->dev,
-					    pool->allocation,
-					    &page->dma);
-	if (page->vaddr) {
-		memset (page->bitmap, 0xff, mapsize);	// bit set == free
-#ifdef	CONFIG_DEBUG_SLAB
-		memset (page->vaddr, POOL_POISON_FREED, pool->allocation);
-#endif
-		list_add (&page->page_list, &pool->page_list);
-		page->in_use = 0;
-	} else {
-		kfree (page);
-		page = 0;
-	}
-	return page;
-}
-
-
-static inline int
-is_page_busy (int blocks, unsigned long *bitmap)
-{
-	while (blocks > 0) {
-		if (*bitmap++ != ~0UL)
-			return 1;
-		blocks -= BITS_PER_LONG;
-	}
-	return 0;
-}
-
-static void
-pool_free_page (struct pci_pool *pool, struct pci_page *page)
-{
-	dma_addr_t	dma = page->dma;
-
-#ifdef	CONFIG_DEBUG_SLAB
-	memset (page->vaddr, POOL_POISON_FREED, pool->allocation);
-#endif
-	pci_free_consistent (pool->dev, pool->allocation, page->vaddr, dma);
-	list_del (&page->page_list);
-	kfree (page);
-}
-
-
-/**
- * pci_pool_destroy - destroys a pool of pci memory blocks.
- * @pool: pci pool that will be destroyed
- * Context: !in_interrupt()
- *
- * 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
-pci_pool_destroy (struct pci_pool *pool)
-{
-	down (&pools_lock);
-	list_del (&pool->pools);
-	if (pool->dev && list_empty (&pool->dev->pools))
-		device_remove_file (&pool->dev->dev, &dev_attr_pools);
-	up (&pools_lock);
-
-	while (!list_empty (&pool->page_list)) {
-		struct pci_page		*page;
-		page = list_entry (pool->page_list.next,
-				struct pci_page, page_list);
-		if (is_page_busy (pool->blocks_per_page, page->bitmap)) {
-			printk (KERN_ERR "pci_pool_destroy %s/%s, %p busy\n",
-				pool->dev ? pci_name(pool->dev) : NULL,
-				pool->name, page->vaddr);
-			/* leak the still-in-use consistent memory */
-			list_del (&page->page_list);
-			kfree (page);
-		} else
-			pool_free_page (pool, page);
-	}
-
-	kfree (pool);
-}
-
-
-/**
- * pci_pool_alloc - get a block of consistent memory
- * @pool: pci pool that will produce the block
- * @mem_flags: SLAB_KERNEL or SLAB_ATOMIC
- * @handle: pointer to dma address of block
- *
- * 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.
- */
-void *
-pci_pool_alloc (struct pci_pool *pool, int mem_flags, dma_addr_t *handle)
-{
-	unsigned long		flags;
-	struct list_head	*entry;
-	struct pci_page		*page;
-	int			map, block;
-	size_t			offset;
-	void			*retval;
-
-restart:
-	spin_lock_irqsave (&pool->lock, flags);
-	list_for_each (entry, &pool->page_list) {
-		int		i;
-		page = list_entry (entry, struct pci_page, page_list);
-		/* 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;
-				goto ready;
-			}
-		}
-	}
-	if (!(page = pool_alloc_page (pool, SLAB_ATOMIC))) {
-		if (mem_flags == SLAB_KERNEL) {
-			DECLARE_WAITQUEUE (wait, current);
-
-			current->state = TASK_INTERRUPTIBLE;
-			add_wait_queue (&pool->waitq, &wait);
-			spin_unlock_irqrestore (&pool->lock, flags);
-
-			schedule_timeout (POOL_TIMEOUT_JIFFIES);
-
-			remove_wait_queue (&pool->waitq, &wait);
-			goto restart;
-		}
-		retval = 0;
-		goto done;
-	}
-
-	clear_bit (0, &page->bitmap [0]);
-	offset = 0;
-ready:
-	page->in_use++;
-	retval = offset + page->vaddr;
-	*handle = offset + page->dma;
-#ifdef	CONFIG_DEBUG_SLAB
-	memset (retval, POOL_POISON_ALLOCATED, pool->size);
-#endif
-done:
-	spin_unlock_irqrestore (&pool->lock, flags);
-	return retval;
-}
-
-
-static struct pci_page *
-pool_find_page (struct pci_pool *pool, dma_addr_t dma)
-{
-	unsigned long		flags;
-	struct list_head	*entry;
-	struct pci_page		*page;
-
-	spin_lock_irqsave (&pool->lock, flags);
-	list_for_each (entry, &pool->page_list) {
-		page = list_entry (entry, struct pci_page, page_list);
-		if (dma < page->dma)
-			continue;
-		if (dma < (page->dma + pool->allocation))
-			goto done;
-	}
-	page = 0;
-done:
-	spin_unlock_irqrestore (&pool->lock, flags);
-	return page;
-}
-
-
-/**
- * pci_pool_free - put block back into pci pool
- * @pool: the pci pool holding the block
- * @vaddr: virtual address of block
- * @dma: dma address of block
- *
- * Caller promises neither device nor driver will again touch this block
- * unless it is first re-allocated.
- */
-void
-pci_pool_free (struct pci_pool *pool, void *vaddr, dma_addr_t dma)
-{
-	struct pci_page		*page;
-	unsigned long		flags;
-	int			map, block;
-
-	if ((page = pool_find_page (pool, dma)) == 0) {
-		printk (KERN_ERR "pci_pool_free %s/%s, %p/%lx (bad dma)\n",
-			pool->dev ? pci_name(pool->dev) : NULL,
-			pool->name, vaddr, (unsigned long) dma);
-		return;
-	}
-
-	block = dma - page->dma;
-	block /= pool->size;
-	map = block / BITS_PER_LONG;
-	block %= BITS_PER_LONG;
-
-#ifdef	CONFIG_DEBUG_SLAB
-	if (((dma - page->dma) + (void *)page->vaddr) != vaddr) {
-		printk (KERN_ERR "pci_pool_free %s/%s, %p (bad vaddr)/%Lx\n",
-			pool->dev ? pci_name(pool->dev) : NULL,
-			pool->name, vaddr, (unsigned long long) dma);
-		return;
-	}
-	if (page->bitmap [map] & (1UL << block)) {
-		printk (KERN_ERR "pci_pool_free %s/%s, dma %Lx already free\n",
-			pool->dev ? pci_name(pool->dev) : NULL,
-			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]);
-	if (waitqueue_active (&pool->waitq))
-		wake_up (&pool->waitq);
-	/*
-	 * Resist a temptation to do
-	 *    if (!is_page_busy(bpp, page->bitmap)) pool_free_page(pool, page);
-	 * it is not interrupt safe. Better have empty pages hang around.
-	 */
-	spin_unlock_irqrestore (&pool->lock, flags);
-}
-
-
-EXPORT_SYMBOL (pci_pool_create);
-EXPORT_SYMBOL (pci_pool_destroy);
-EXPORT_SYMBOL (pci_pool_alloc);
-EXPORT_SYMBOL (pci_pool_free);
diff -Nru a/drivers/pci/probe.c b/drivers/pci/probe.c
--- a/drivers/pci/probe.c	Fri Jan 30 12:20:30 2004
+++ b/drivers/pci/probe.c	Fri Jan 30 12:20:30 2004
@@ -407,8 +407,6 @@
 	sprintf(pci_name(dev), "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
 		dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
 
-	INIT_LIST_HEAD(&dev->pools);
-
 	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
 	class >>= 8;				    /* upper 3 bytes */
 	dev->class = class;


-- 
Deepak Saxena - dsaxena@plexity.net