2008-06-29 10:20:11

by Dmitry Baryshkov

[permalink] [raw]
Subject: [PATCH 2/2] x86: use generic per-device dma coherent allocator

Signed-off-by: Dmitry Baryshkov <[email protected]>
---
arch/x86/Kconfig | 1 +
arch/x86/kernel/pci-dma.c | 122 +----------------------------------------
include/asm-x86/dma-mapping.h | 22 +-------
3 files changed, 4 insertions(+), 141 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index e0edaaa..9d4714e 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -25,6 +25,7 @@ config X86
select HAVE_KRETPROBES
select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
select HAVE_ARCH_KGDB if !X86_VOYAGER
+ select HAVE_GENERIC_DMA_COHERENT if X86_32

config ARCH_DEFCONFIG
string
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index dc00a13..b75c81a 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -197,124 +197,6 @@ static __init int iommu_setup(char *p)
}
early_param("iommu", iommu_setup);

-#ifdef CONFIG_X86_32
-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;
- int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1);
-
- pages >>= PAGE_SHIFT;
-
- if (!mem)
- return ERR_PTR(-EINVAL);
-
- pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
- err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages));
- if (err != 0)
- return ERR_PTR(err);
- return mem->virt_base + (pos << PAGE_SHIFT);
-}
-EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
-
-static int dma_alloc_from_coherent_mem(struct device *dev, ssize_t size,
- dma_addr_t *dma_handle, void **ret)
-{
- struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
- int order = get_order(size);
-
- if (mem) {
- int page = bitmap_find_free_region(mem->bitmap, mem->size,
- order);
- if (page >= 0) {
- *dma_handle = mem->device_base + (page << PAGE_SHIFT);
- *ret = mem->virt_base + (page << PAGE_SHIFT);
- memset(*ret, 0, size);
- }
- if (mem->flags & DMA_MEMORY_EXCLUSIVE)
- *ret = NULL;
- }
- return (mem != NULL);
-}
-
-static int dma_release_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;
-}
-#else
-#define dma_alloc_from_coherent_mem(dev, size, handle, ret) (0)
-#define dma_release_coherent(dev, order, vaddr) (0)
-#endif /* CONFIG_X86_32 */
-
int dma_supported(struct device *dev, u64 mask)
{
#ifdef CONFIG_PCI
@@ -383,7 +265,7 @@ dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
/* ignore region specifiers */
gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);

- if (dma_alloc_from_coherent_mem(dev, size, dma_handle, &memory))
+ if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
return memory;

if (!dev) {
@@ -486,7 +368,7 @@ void dma_free_coherent(struct device *dev, size_t size,
{
int order = get_order(size);
WARN_ON(irqs_disabled()); /* for portability */
- if (dma_release_coherent(dev, order, vaddr))
+ if (dma_release_from_coherent(dev, order, vaddr))
return;
if (dma_ops->unmap_single)
dma_ops->unmap_single(dev, bus, size, 0);
diff --git a/include/asm-x86/dma-mapping.h b/include/asm-x86/dma-mapping.h
index a1a4dc7..c68f360 100644
--- a/include/asm-x86/dma-mapping.h
+++ b/include/asm-x86/dma-mapping.h
@@ -213,25 +213,5 @@ static inline int dma_get_cache_alignment(void)

#define dma_is_consistent(d, h) (1)

-#ifdef CONFIG_X86_32
-# define ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
-struct dma_coherent_mem {
- void *virt_base;
- u32 device_base;
- int size;
- int flags;
- unsigned long *bitmap;
-};
-
-extern int
-dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
- dma_addr_t device_addr, size_t size, int flags);
-
-extern void
-dma_release_declared_memory(struct device *dev);
-
-extern void *
-dma_mark_declared_memory_occupied(struct device *dev,
- dma_addr_t device_addr, size_t size);
-#endif /* CONFIG_X86_32 */
+#include <asm-generic/dma-coherent.h>
#endif
--
1.5.5.4


--
With best wishes
Dmitry