Merge branch 'dmapool' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'dmapool' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: pool: Improve memory usage for devices which can't cross boundaries Change dmapool free block management dmapool: Tidy up includes and add comments dmapool: Validate parameters to dma_pool_create Avoid taking waitqueue lock in dmapool dmapool: Fix style problems Move dmapool.c to mm/ directory
This commit is contained in:
Linus Torvalds
commit
b297d520b9
@ -5,7 +5,7 @@ obj-y := core.o sys.o bus.o dd.o \
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cpu.o firmware.o init.o map.o devres.o \
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attribute_container.o transport_class.o
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obj-y += power/
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obj-$(CONFIG_HAS_DMA) += dma-mapping.o dmapool.o
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obj-$(CONFIG_HAS_DMA) += dma-mapping.o
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obj-$(CONFIG_ISA) += isa.o
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obj-$(CONFIG_FW_LOADER) += firmware_class.o
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obj-$(CONFIG_NUMA) += node.o
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@ -1,481 +0,0 @@
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#include <linux/device.h>
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#include <linux/mm.h>
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#include <asm/io.h> /* Needed for i386 to build */
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#include <linux/dma-mapping.h>
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#include <linux/dmapool.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/poison.h>
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#include <linux/sched.h>
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/*
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* Pool allocator ... wraps the dma_alloc_coherent page allocator, so
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* small blocks are easily used by drivers for bus mastering controllers.
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* This should probably be sharing the guts of the slab allocator.
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*/
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struct dma_pool { /* the pool */
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struct list_head page_list;
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spinlock_t lock;
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size_t blocks_per_page;
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size_t size;
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struct device *dev;
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size_t allocation;
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char name [32];
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wait_queue_head_t waitq;
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struct list_head pools;
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};
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struct dma_page { /* cacheable header for 'allocation' bytes */
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struct list_head page_list;
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void *vaddr;
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dma_addr_t dma;
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unsigned in_use;
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unsigned long bitmap [0];
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};
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#define POOL_TIMEOUT_JIFFIES ((100 /* msec */ * HZ) / 1000)
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static DEFINE_MUTEX (pools_lock);
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static ssize_t
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show_pools (struct device *dev, struct device_attribute *attr, char *buf)
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{
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unsigned temp;
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unsigned size;
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char *next;
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struct dma_page *page;
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struct dma_pool *pool;
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next = buf;
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size = PAGE_SIZE;
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temp = scnprintf(next, size, "poolinfo - 0.1\n");
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size -= temp;
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next += temp;
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mutex_lock(&pools_lock);
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list_for_each_entry(pool, &dev->dma_pools, pools) {
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unsigned pages = 0;
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unsigned blocks = 0;
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list_for_each_entry(page, &pool->page_list, page_list) {
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pages++;
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blocks += page->in_use;
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}
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/* per-pool info, no real statistics yet */
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temp = scnprintf(next, size, "%-16s %4u %4Zu %4Zu %2u\n",
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pool->name,
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blocks, pages * pool->blocks_per_page,
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pool->size, pages);
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size -= temp;
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next += temp;
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}
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mutex_unlock(&pools_lock);
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return PAGE_SIZE - size;
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}
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static DEVICE_ATTR (pools, S_IRUGO, show_pools, NULL);
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/**
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* dma_pool_create - Creates a pool of consistent memory blocks, for dma.
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* @name: name of pool, for diagnostics
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* @dev: device that will be doing the DMA
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* @size: size of the blocks in this pool.
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* @align: alignment requirement for blocks; must be a power of two
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* @allocation: returned blocks won't cross this boundary (or zero)
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* Context: !in_interrupt()
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*
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* Returns a dma allocation pool with the requested characteristics, or
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* null if one can't be created. Given one of these pools, dma_pool_alloc()
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* may be used to allocate memory. Such memory will all have "consistent"
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* DMA mappings, accessible by the device and its driver without using
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* cache flushing primitives. The actual size of blocks allocated may be
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* larger than requested because of alignment.
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*
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* If allocation is nonzero, objects returned from dma_pool_alloc() won't
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* cross that size boundary. This is useful for devices which have
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* addressing restrictions on individual DMA transfers, such as not crossing
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* boundaries of 4KBytes.
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*/
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struct dma_pool *
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dma_pool_create (const char *name, struct device *dev,
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size_t size, size_t align, size_t allocation)
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{
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struct dma_pool *retval;
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if (align == 0)
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align = 1;
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if (size == 0)
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return NULL;
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else if (size < align)
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size = align;
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else if ((size % align) != 0) {
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size += align + 1;
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size &= ~(align - 1);
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}
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if (allocation == 0) {
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if (PAGE_SIZE < size)
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allocation = size;
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else
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allocation = PAGE_SIZE;
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// FIXME: round up for less fragmentation
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} else if (allocation < size)
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return NULL;
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if (!(retval = kmalloc_node (sizeof *retval, GFP_KERNEL, dev_to_node(dev))))
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return retval;
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strlcpy (retval->name, name, sizeof retval->name);
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retval->dev = dev;
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INIT_LIST_HEAD (&retval->page_list);
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spin_lock_init (&retval->lock);
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retval->size = size;
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retval->allocation = allocation;
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retval->blocks_per_page = allocation / size;
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init_waitqueue_head (&retval->waitq);
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if (dev) {
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int ret;
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mutex_lock(&pools_lock);
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if (list_empty (&dev->dma_pools))
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ret = device_create_file (dev, &dev_attr_pools);
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else
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ret = 0;
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/* note: not currently insisting "name" be unique */
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if (!ret)
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list_add (&retval->pools, &dev->dma_pools);
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else {
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kfree(retval);
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retval = NULL;
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}
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mutex_unlock(&pools_lock);
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} else
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INIT_LIST_HEAD (&retval->pools);
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return retval;
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}
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static struct dma_page *
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pool_alloc_page (struct dma_pool *pool, gfp_t mem_flags)
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{
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struct dma_page *page;
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int mapsize;
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mapsize = pool->blocks_per_page;
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mapsize = (mapsize + BITS_PER_LONG - 1) / BITS_PER_LONG;
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mapsize *= sizeof (long);
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page = kmalloc(mapsize + sizeof *page, mem_flags);
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if (!page)
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return NULL;
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page->vaddr = dma_alloc_coherent (pool->dev,
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pool->allocation,
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&page->dma,
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mem_flags);
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if (page->vaddr) {
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memset (page->bitmap, 0xff, mapsize); // bit set == free
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#ifdef CONFIG_DEBUG_SLAB
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memset (page->vaddr, POOL_POISON_FREED, pool->allocation);
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#endif
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list_add (&page->page_list, &pool->page_list);
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page->in_use = 0;
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} else {
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kfree (page);
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page = NULL;
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}
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return page;
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}
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static inline int
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is_page_busy (int blocks, unsigned long *bitmap)
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{
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while (blocks > 0) {
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if (*bitmap++ != ~0UL)
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return 1;
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blocks -= BITS_PER_LONG;
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}
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return 0;
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}
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static void
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pool_free_page (struct dma_pool *pool, struct dma_page *page)
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{
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dma_addr_t dma = page->dma;
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#ifdef CONFIG_DEBUG_SLAB
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memset (page->vaddr, POOL_POISON_FREED, pool->allocation);
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#endif
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dma_free_coherent (pool->dev, pool->allocation, page->vaddr, dma);
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list_del (&page->page_list);
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kfree (page);
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}
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/**
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* dma_pool_destroy - destroys a pool of dma memory blocks.
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* @pool: dma pool that will be destroyed
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* Context: !in_interrupt()
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*
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* Caller guarantees that no more memory from the pool is in use,
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* and that nothing will try to use the pool after this call.
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*/
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void
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dma_pool_destroy (struct dma_pool *pool)
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{
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mutex_lock(&pools_lock);
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list_del (&pool->pools);
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if (pool->dev && list_empty (&pool->dev->dma_pools))
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device_remove_file (pool->dev, &dev_attr_pools);
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mutex_unlock(&pools_lock);
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while (!list_empty (&pool->page_list)) {
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struct dma_page *page;
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page = list_entry (pool->page_list.next,
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struct dma_page, page_list);
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if (is_page_busy (pool->blocks_per_page, page->bitmap)) {
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if (pool->dev)
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dev_err(pool->dev, "dma_pool_destroy %s, %p busy\n",
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pool->name, page->vaddr);
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else
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printk (KERN_ERR "dma_pool_destroy %s, %p busy\n",
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pool->name, page->vaddr);
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/* leak the still-in-use consistent memory */
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list_del (&page->page_list);
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kfree (page);
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} else
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pool_free_page (pool, page);
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}
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kfree (pool);
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}
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/**
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* dma_pool_alloc - get a block of consistent memory
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* @pool: dma pool that will produce the block
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* @mem_flags: GFP_* bitmask
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* @handle: pointer to dma address of block
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*
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* This returns the kernel virtual address of a currently unused block,
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* and reports its dma address through the handle.
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* If such a memory block can't be allocated, null is returned.
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*/
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void *
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dma_pool_alloc (struct dma_pool *pool, gfp_t mem_flags, dma_addr_t *handle)
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{
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unsigned long flags;
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struct dma_page *page;
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int map, block;
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size_t offset;
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void *retval;
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restart:
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spin_lock_irqsave (&pool->lock, flags);
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list_for_each_entry(page, &pool->page_list, page_list) {
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int i;
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/* only cachable accesses here ... */
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for (map = 0, i = 0;
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i < pool->blocks_per_page;
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i += BITS_PER_LONG, map++) {
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if (page->bitmap [map] == 0)
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continue;
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block = ffz (~ page->bitmap [map]);
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if ((i + block) < pool->blocks_per_page) {
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clear_bit (block, &page->bitmap [map]);
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offset = (BITS_PER_LONG * map) + block;
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offset *= pool->size;
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goto ready;
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}
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}
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}
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if (!(page = pool_alloc_page (pool, GFP_ATOMIC))) {
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if (mem_flags & __GFP_WAIT) {
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DECLARE_WAITQUEUE (wait, current);
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__set_current_state(TASK_INTERRUPTIBLE);
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add_wait_queue (&pool->waitq, &wait);
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spin_unlock_irqrestore (&pool->lock, flags);
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schedule_timeout (POOL_TIMEOUT_JIFFIES);
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remove_wait_queue (&pool->waitq, &wait);
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goto restart;
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}
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retval = NULL;
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goto done;
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}
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clear_bit (0, &page->bitmap [0]);
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offset = 0;
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ready:
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page->in_use++;
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retval = offset + page->vaddr;
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*handle = offset + page->dma;
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#ifdef CONFIG_DEBUG_SLAB
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memset (retval, POOL_POISON_ALLOCATED, pool->size);
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#endif
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||||
done:
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spin_unlock_irqrestore (&pool->lock, flags);
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return retval;
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||||
}
|
||||
|
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|
||||
static struct dma_page *
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pool_find_page (struct dma_pool *pool, dma_addr_t dma)
|
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{
|
||||
unsigned long flags;
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||||
struct dma_page *page;
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||||
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||||
spin_lock_irqsave (&pool->lock, flags);
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list_for_each_entry(page, &pool->page_list, page_list) {
|
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if (dma < page->dma)
|
||||
continue;
|
||||
if (dma < (page->dma + pool->allocation))
|
||||
goto done;
|
||||
}
|
||||
page = NULL;
|
||||
done:
|
||||
spin_unlock_irqrestore (&pool->lock, flags);
|
||||
return page;
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* dma_pool_free - put block back into dma pool
|
||||
* @pool: the dma 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
|
||||
dma_pool_free (struct dma_pool *pool, void *vaddr, dma_addr_t dma)
|
||||
{
|
||||
struct dma_page *page;
|
||||
unsigned long flags;
|
||||
int map, block;
|
||||
|
||||
if ((page = pool_find_page(pool, dma)) == NULL) {
|
||||
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;
|
||||
}
|
||||
|
||||
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) {
|
||||
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;
|
||||
}
|
||||
if (page->bitmap [map] & (1UL << block)) {
|
||||
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;
|
||||
}
|
||||
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);
|
||||
* Better have a few empty pages hang around.
|
||||
*/
|
||||
spin_unlock_irqrestore (&pool->lock, flags);
|
||||
}
|
||||
|
||||
/*
|
||||
* Managed DMA pool
|
||||
*/
|
||||
static void dmam_pool_release(struct device *dev, void *res)
|
||||
{
|
||||
struct dma_pool *pool = *(struct dma_pool **)res;
|
||||
|
||||
dma_pool_destroy(pool);
|
||||
}
|
||||
|
||||
static int dmam_pool_match(struct device *dev, void *res, void *match_data)
|
||||
{
|
||||
return *(struct dma_pool **)res == match_data;
|
||||
}
|
||||
|
||||
/**
|
||||
* dmam_pool_create - Managed dma_pool_create()
|
||||
* @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
|
||||
* @allocation: returned blocks won't cross this boundary (or zero)
|
||||
*
|
||||
* Managed dma_pool_create(). DMA pool created with this function is
|
||||
* automatically destroyed on driver detach.
|
||||
*/
|
||||
struct dma_pool *dmam_pool_create(const char *name, struct device *dev,
|
||||
size_t size, size_t align, size_t allocation)
|
||||
{
|
||||
struct dma_pool **ptr, *pool;
|
||||
|
||||
ptr = devres_alloc(dmam_pool_release, sizeof(*ptr), GFP_KERNEL);
|
||||
if (!ptr)
|
||||
return NULL;
|
||||
|
||||
pool = *ptr = dma_pool_create(name, dev, size, align, allocation);
|
||||
if (pool)
|
||||
devres_add(dev, ptr);
|
||||
else
|
||||
devres_free(ptr);
|
||||
|
||||
return pool;
|
||||
}
|
||||
|
||||
/**
|
||||
* dmam_pool_destroy - Managed dma_pool_destroy()
|
||||
* @pool: dma pool that will be destroyed
|
||||
*
|
||||
* Managed dma_pool_destroy().
|
||||
*/
|
||||
void dmam_pool_destroy(struct dma_pool *pool)
|
||||
{
|
||||
struct device *dev = pool->dev;
|
||||
|
||||
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);
|
||||
@ -16,6 +16,7 @@ obj-y := bootmem.o filemap.o mempool.o oom_kill.o fadvise.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
|
||||
|
||||
500
mm/dmapool.c
Normal file
500
mm/dmapool.c
Normal file
@ -0,0 +1,500 @@
|
||||
/*
|
||||
* 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/dma-mapping.h>
|
||||
#include <linux/dmapool.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>
|
||||
#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 size;
|
||||
struct device *dev;
|
||||
size_t allocation;
|
||||
size_t boundary;
|
||||
char name[32];
|
||||
wait_queue_head_t waitq;
|
||||
struct list_head pools;
|
||||
};
|
||||
|
||||
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;
|
||||
};
|
||||
|
||||
#define POOL_TIMEOUT_JIFFIES ((100 /* msec */ * HZ) / 1000)
|
||||
|
||||
static DEFINE_MUTEX(pools_lock);
|
||||
|
||||
static ssize_t
|
||||
show_pools(struct device *dev, struct device_attribute *attr, char *buf)
|
||||
{
|
||||
unsigned temp;
|
||||
unsigned size;
|
||||
char *next;
|
||||
struct dma_page *page;
|
||||
struct dma_pool *pool;
|
||||
|
||||
next = buf;
|
||||
size = PAGE_SIZE;
|
||||
|
||||
temp = scnprintf(next, size, "poolinfo - 0.1\n");
|
||||
size -= temp;
|
||||
next += temp;
|
||||
|
||||
mutex_lock(&pools_lock);
|
||||
list_for_each_entry(pool, &dev->dma_pools, pools) {
|
||||
unsigned pages = 0;
|
||||
unsigned blocks = 0;
|
||||
|
||||
list_for_each_entry(page, &pool->page_list, page_list) {
|
||||
pages++;
|
||||
blocks += page->in_use;
|
||||
}
|
||||
|
||||
/* 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;
|
||||
}
|
||||
mutex_unlock(&pools_lock);
|
||||
|
||||
return PAGE_SIZE - size;
|
||||
}
|
||||
|
||||
static DEVICE_ATTR(pools, S_IRUGO, show_pools, NULL);
|
||||
|
||||
/**
|
||||
* dma_pool_create - Creates a pool of consistent memory blocks, for dma.
|
||||
* @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()
|
||||
*
|
||||
* 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"
|
||||
* 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 @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 boundary)
|
||||
{
|
||||
struct dma_pool *retval;
|
||||
size_t allocation;
|
||||
|
||||
if (align == 0) {
|
||||
align = 1;
|
||||
} else if (align & (align - 1)) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
if (size == 0) {
|
||||
return NULL;
|
||||
} else if (size < 4) {
|
||||
size = 4;
|
||||
}
|
||||
|
||||
if ((size % align) != 0)
|
||||
size = ALIGN(size, align);
|
||||
|
||||
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));
|
||||
|
||||
retval->dev = dev;
|
||||
|
||||
INIT_LIST_HEAD(&retval->page_list);
|
||||
spin_lock_init(&retval->lock);
|
||||
retval->size = size;
|
||||
retval->boundary = boundary;
|
||||
retval->allocation = allocation;
|
||||
init_waitqueue_head(&retval->waitq);
|
||||
|
||||
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 {
|
||||
kfree(retval);
|
||||
retval = NULL;
|
||||
}
|
||||
mutex_unlock(&pools_lock);
|
||||
} else
|
||||
INIT_LIST_HEAD(&retval->pools);
|
||||
|
||||
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)
|
||||
{
|
||||
struct dma_page *page;
|
||||
|
||||
page = kmalloc(sizeof(*page), mem_flags);
|
||||
if (!page)
|
||||
return NULL;
|
||||
page->vaddr = dma_alloc_coherent(pool->dev, pool->allocation,
|
||||
&page->dma, mem_flags);
|
||||
if (page->vaddr) {
|
||||
#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(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 CONFIG_DEBUG_SLAB
|
||||
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
|
||||
* 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 dma_pool_destroy(struct dma_pool *pool)
|
||||
{
|
||||
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);
|
||||
mutex_unlock(&pools_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)) {
|
||||
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);
|
||||
}
|
||||
|
||||
kfree(pool);
|
||||
}
|
||||
EXPORT_SYMBOL(dma_pool_destroy);
|
||||
|
||||
/**
|
||||
* dma_pool_alloc - get a block of consistent 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,
|
||||
* 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_page *page;
|
||||
size_t offset;
|
||||
void *retval;
|
||||
|
||||
spin_lock_irqsave(&pool->lock, flags);
|
||||
restart:
|
||||
list_for_each_entry(page, &pool->page_list, page_list) {
|
||||
if (page->offset < pool->allocation)
|
||||
goto ready;
|
||||
}
|
||||
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);
|
||||
spin_unlock_irqrestore(&pool->lock, flags);
|
||||
|
||||
schedule_timeout(POOL_TIMEOUT_JIFFIES);
|
||||
|
||||
spin_lock_irqsave(&pool->lock, flags);
|
||||
__remove_wait_queue(&pool->waitq, &wait);
|
||||
goto restart;
|
||||
}
|
||||
retval = NULL;
|
||||
goto done;
|
||||
}
|
||||
|
||||
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
|
||||
memset(retval, POOL_POISON_ALLOCATED, pool->size);
|
||||
#endif
|
||||
done:
|
||||
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)
|
||||
{
|
||||
unsigned long flags;
|
||||
struct dma_page *page;
|
||||
|
||||
spin_lock_irqsave(&pool->lock, flags);
|
||||
list_for_each_entry(page, &pool->page_list, page_list) {
|
||||
if (dma < page->dma)
|
||||
continue;
|
||||
if (dma < (page->dma + pool->allocation))
|
||||
goto done;
|
||||
}
|
||||
page = NULL;
|
||||
done:
|
||||
spin_unlock_irqrestore(&pool->lock, flags);
|
||||
return page;
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_pool_free - put block back into dma pool
|
||||
* @pool: the dma 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 dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma)
|
||||
{
|
||||
struct dma_page *page;
|
||||
unsigned long flags;
|
||||
unsigned int offset;
|
||||
|
||||
page = pool_find_page(pool, dma);
|
||||
if (!page) {
|
||||
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 CONFIG_DEBUG_SLAB
|
||||
if ((dma - page->dma) != offset) {
|
||||
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;
|
||||
}
|
||||
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;
|
||||
}
|
||||
}
|
||||
memset(vaddr, POOL_POISON_FREED, pool->size);
|
||||
#endif
|
||||
|
||||
spin_lock_irqsave(&pool->lock, flags);
|
||||
page->in_use--;
|
||||
*(int *)vaddr = page->offset;
|
||||
page->offset = offset;
|
||||
if (waitqueue_active(&pool->waitq))
|
||||
wake_up_locked(&pool->waitq);
|
||||
/*
|
||||
* 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);
|
||||
|
||||
/*
|
||||
* Managed DMA pool
|
||||
*/
|
||||
static void dmam_pool_release(struct device *dev, void *res)
|
||||
{
|
||||
struct dma_pool *pool = *(struct dma_pool **)res;
|
||||
|
||||
dma_pool_destroy(pool);
|
||||
}
|
||||
|
||||
static int dmam_pool_match(struct device *dev, void *res, void *match_data)
|
||||
{
|
||||
return *(struct dma_pool **)res == match_data;
|
||||
}
|
||||
|
||||
/**
|
||||
* dmam_pool_create - Managed dma_pool_create()
|
||||
* @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
|
||||
* @allocation: returned blocks won't cross this boundary (or zero)
|
||||
*
|
||||
* Managed dma_pool_create(). DMA pool created with this function is
|
||||
* automatically destroyed on driver detach.
|
||||
*/
|
||||
struct dma_pool *dmam_pool_create(const char *name, struct device *dev,
|
||||
size_t size, size_t align, size_t allocation)
|
||||
{
|
||||
struct dma_pool **ptr, *pool;
|
||||
|
||||
ptr = devres_alloc(dmam_pool_release, sizeof(*ptr), GFP_KERNEL);
|
||||
if (!ptr)
|
||||
return NULL;
|
||||
|
||||
pool = *ptr = dma_pool_create(name, dev, size, align, allocation);
|
||||
if (pool)
|
||||
devres_add(dev, ptr);
|
||||
else
|
||||
devres_free(ptr);
|
||||
|
||||
return pool;
|
||||
}
|
||||
EXPORT_SYMBOL(dmam_pool_create);
|
||||
|
||||
/**
|
||||
* dmam_pool_destroy - Managed dma_pool_destroy()
|
||||
* @pool: dma pool that will be destroyed
|
||||
*
|
||||
* Managed dma_pool_destroy().
|
||||
*/
|
||||
void dmam_pool_destroy(struct dma_pool *pool)
|
||||
{
|
||||
struct device *dev = pool->dev;
|
||||
|
||||
dma_pool_destroy(pool);
|
||||
WARN_ON(devres_destroy(dev, dmam_pool_release, dmam_pool_match, pool));
|
||||
}
|
||||
EXPORT_SYMBOL(dmam_pool_destroy);
|
||||
Loading…
Reference in New Issue
Block a user