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authorMing Lei <tom.leiming@gmail.com>2009-07-12 21:44:55 +0800
committerGreg Kroah-Hartman <gregkh@suse.de>2009-09-15 09:50:47 -0700
commita56af87648054089d89874b52e3fc23ed4f274ad (patch)
tree81714be5cc39f830b4acf55ec782b46f36e67ebe /kernel/dma-coherent.c
parent162dd4212409fd2d36ff22547ea821bf3e86bcc9 (diff)
driver-core: move dma-coherent.c from kernel to driver/base
Placing dma-coherent.c in driver/base is better than in kernel, since it contains code to do per-device coherent dma memory handling. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'kernel/dma-coherent.c')
-rw-r--r--kernel/dma-coherent.c176
1 files changed, 0 insertions, 176 deletions
diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c
deleted file mode 100644
index 962a3b574f2..00000000000
--- a/kernel/dma-coherent.c
+++ /dev/null
@@ -1,176 +0,0 @@
-/*
- * Coherent per-device memory handling.
- * Borrowed from i386
- */
-#include <linux/kernel.h>
-#include <linux/dma-mapping.h>
-
-struct dma_coherent_mem {
- void *virt_base;
- u32 device_base;
- int size;
- int flags;
- unsigned long *bitmap;
-};
-
-int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
- dma_addr_t device_addr, size_t size, int flags)
-{
- void __iomem *mem_base = NULL;
- int pages = size >> PAGE_SHIFT;
- int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
-
- if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
- goto out;
- if (!size)
- goto out;
- if (dev->dma_mem)
- goto out;
-
- /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
-
- mem_base = ioremap(bus_addr, size);
- if (!mem_base)
- goto out;
-
- dev->dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
- if (!dev->dma_mem)
- goto out;
- dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!dev->dma_mem->bitmap)
- goto free1_out;
-
- dev->dma_mem->virt_base = mem_base;
- dev->dma_mem->device_base = device_addr;
- dev->dma_mem->size = pages;
- dev->dma_mem->flags = flags;
-
- if (flags & DMA_MEMORY_MAP)
- return DMA_MEMORY_MAP;
-
- return DMA_MEMORY_IO;
-
- free1_out:
- kfree(dev->dma_mem);
- out:
- if (mem_base)
- iounmap(mem_base);
- return 0;
-}
-EXPORT_SYMBOL(dma_declare_coherent_memory);
-
-void dma_release_declared_memory(struct device *dev)
-{
- struct dma_coherent_mem *mem = dev->dma_mem;
-
- if (!mem)
- return;
- dev->dma_mem = NULL;
- iounmap(mem->virt_base);
- kfree(mem->bitmap);
- kfree(mem);
-}
-EXPORT_SYMBOL(dma_release_declared_memory);
-
-void *dma_mark_declared_memory_occupied(struct device *dev,
- dma_addr_t device_addr, size_t size)
-{
- struct dma_coherent_mem *mem = dev->dma_mem;
- int pos, err;
-
- size += device_addr & ~PAGE_MASK;
-
- if (!mem)
- return ERR_PTR(-EINVAL);
-
- pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
- err = bitmap_allocate_region(mem->bitmap, pos, get_order(size));
- if (err != 0)
- return ERR_PTR(err);
- return mem->virt_base + (pos << PAGE_SHIFT);
-}
-EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
-
-/**
- * dma_alloc_from_coherent() - try to allocate memory from the per-device coherent area
- *
- * @dev: device from which we allocate memory
- * @size: size of requested memory area
- * @dma_handle: This will be filled with the correct dma handle
- * @ret: This pointer will be filled with the virtual address
- * to allocated area.
- *
- * This function should be only called from per-arch dma_alloc_coherent()
- * to support allocation from per-device coherent memory pools.
- *
- * Returns 0 if dma_alloc_coherent should continue with allocating from
- * generic memory areas, or !0 if dma_alloc_coherent should return @ret.
- */
-int dma_alloc_from_coherent(struct device *dev, ssize_t size,
- dma_addr_t *dma_handle, void **ret)
-{
- struct dma_coherent_mem *mem;
- int order = get_order(size);
- int pageno;
-
- if (!dev)
- return 0;
- mem = dev->dma_mem;
- if (!mem)
- return 0;
-
- *ret = NULL;
-
- if (unlikely(size > (mem->size << PAGE_SHIFT)))
- goto err;
-
- pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
- if (unlikely(pageno < 0))
- goto err;
-
- /*
- * Memory was found in the per-device area.
- */
- *dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
- *ret = mem->virt_base + (pageno << PAGE_SHIFT);
- memset(*ret, 0, size);
-
- return 1;
-
-err:
- /*
- * In the case where the allocation can not be satisfied from the
- * per-device area, try to fall back to generic memory if the
- * constraints allow it.
- */
- return mem->flags & DMA_MEMORY_EXCLUSIVE;
-}
-EXPORT_SYMBOL(dma_alloc_from_coherent);
-
-/**
- * dma_release_from_coherent() - try to free the memory allocated from per-device coherent memory pool
- * @dev: device from which the memory was allocated
- * @order: the order of pages allocated
- * @vaddr: virtual address of allocated pages
- *
- * This checks whether the memory was allocated from the per-device
- * coherent memory pool and if so, releases that memory.
- *
- * Returns 1 if we correctly released the memory, or 0 if
- * dma_release_coherent() should proceed with releasing memory from
- * generic pools.
- */
-int dma_release_from_coherent(struct device *dev, int order, void *vaddr)
-{
- struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
-
- if (mem && vaddr >= mem->virt_base && vaddr <
- (mem->virt_base + (mem->size << PAGE_SHIFT))) {
- int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
-
- bitmap_release_region(mem->bitmap, page, order);
- return 1;
- }
- return 0;
-}
-EXPORT_SYMBOL(dma_release_from_coherent);