Merge branch 'linus' into core/generic-dma-coherent
authorIngo Molnar <mingo@elte.hu>
Mon, 28 Jul 2008 22:07:55 +0000 (00:07 +0200)
committerIngo Molnar <mingo@elte.hu>
Mon, 28 Jul 2008 22:07:55 +0000 (00:07 +0200)
Conflicts:

arch/x86/Kconfig

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 files changed:
arch/arm/Kconfig
arch/arm/mm/consistent.c
arch/cris/arch-v32/drivers/Kconfig
arch/cris/arch-v32/drivers/pci/dma.c
arch/sh/Kconfig
arch/sh/mm/consistent.c
arch/x86/Kconfig
arch/x86/kernel/pci-dma.c
include/asm-arm/dma-mapping.h
include/asm-cris/dma-mapping.h
include/asm-generic/dma-coherent.h [new file with mode: 0644]
include/asm-sh/dma-mapping.h
include/asm-x86/dma-mapping.h
init/Kconfig
kernel/Makefile
kernel/dma-coherent.c [new file with mode: 0644]

index c8f5282..652cd32 100644 (file)
@@ -17,6 +17,7 @@ config ARM
        select HAVE_KRETPROBES if (HAVE_KPROBES)
        select HAVE_FTRACE if (!XIP_KERNEL)
        select HAVE_DYNAMIC_FTRACE if (HAVE_FTRACE)
+       select HAVE_GENERIC_DMA_COHERENT
        help
          The ARM series is a line of low-power-consumption RISC chip designs
          licensed by ARM Ltd and targeted at embedded applications and
index 333a82a..db7b3e3 100644 (file)
@@ -274,6 +274,11 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
 void *
 dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp)
 {
+       void *memory;
+
+       if (dma_alloc_from_coherent(dev, size, handle, &memory))
+               return memory;
+
        if (arch_is_coherent()) {
                void *virt;
 
@@ -362,6 +367,9 @@ void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr
 
        WARN_ON(irqs_disabled());
 
+       if (dma_release_from_coherent(dev, get_order(size), cpu_addr))
+               return;
+
        if (arch_is_coherent()) {
                kfree(cpu_addr);
                return;
index 2a92cb1..7a64fce 100644 (file)
@@ -641,6 +641,7 @@ config PCI
        bool
        depends on ETRAX_CARDBUS
        default y
+       select HAVE_GENERIC_DMA_COHERENT
 
 config ETRAX_IOP_FW_LOAD
        tristate "IO-processor hotplug firmware loading support"
index e036465..fbe6595 100644 (file)
 #include <linux/pci.h>
 #include <asm/io.h>
 
-struct dma_coherent_mem {
-       void            *virt_base;
-       u32             device_base;
-       int             size;
-       int             flags;
-       unsigned long   *bitmap;
-};
-
 void *dma_alloc_coherent(struct device *dev, size_t size,
                           dma_addr_t *dma_handle, gfp_t gfp)
 {
        void *ret;
-       struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
        int order = get_order(size);
        /* ignore region specifiers */
        gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
 
-       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);
-                       return ret;
-               }
-               if (mem->flags & DMA_MEMORY_EXCLUSIVE)
-                       return NULL;
-       }
+       if (dma_alloc_from_coherent(dev, size, dma_handle, &ret))
+               return ret;
 
        if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
                gfp |= GFP_DMA;
@@ -60,90 +41,9 @@ void *dma_alloc_coherent(struct device *dev, size_t size,
 void dma_free_coherent(struct device *dev, size_t size,
                         void *vaddr, dma_addr_t dma_handle)
 {
-       struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
        int order = get_order(size);
 
-       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);
-       } else
+       if (!dma_release_from_coherent(dev, order, vaddr))
                free_pages((unsigned long)vaddr, order);
 }
 
-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;
-       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 iounmap_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);
- iounmap_out:
-       iounmap(mem_base);
- out:
-       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 pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
-       int pos, err;
-
-       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);
index 7bfb0d2..0b88dc4 100644 (file)
@@ -11,6 +11,7 @@ config SUPERH
        select HAVE_CLK
        select HAVE_IDE
        select HAVE_OPROFILE
+       select HAVE_GENERIC_DMA_COHERENT
        help
          The SuperH is a RISC processor targeted for use in embedded systems
          and consumer electronics; it was also used in the Sega Dreamcast
index 8277982..b2ce014 100644 (file)
@@ -28,21 +28,10 @@ void *dma_alloc_coherent(struct device *dev, size_t size,
                           dma_addr_t *dma_handle, gfp_t gfp)
 {
        void *ret, *ret_nocache;
-       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);
-                       return ret;
-               }
-               if (mem->flags & DMA_MEMORY_EXCLUSIVE)
-                       return NULL;
-       }
+       if (dma_alloc_from_coherent(dev, size, dma_handle, &ret))
+               return ret;
 
        ret = (void *)__get_free_pages(gfp, order);
        if (!ret)
@@ -72,11 +61,7 @@ void dma_free_coherent(struct device *dev, size_t size,
        struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
        int order = get_order(size);
 
-       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);
-       } else {
+       if (!dma_release_from_coherent(dev, order, vaddr)) {
                WARN_ON(irqs_disabled());       /* for portability */
                BUG_ON(mem && mem->flags & DMA_MEMORY_EXCLUSIVE);
                free_pages((unsigned long)phys_to_virt(dma_handle), order);
@@ -85,83 +70,6 @@ void dma_free_coherent(struct device *dev, size_t size,
 }
 EXPORT_SYMBOL(dma_free_coherent);
 
-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_nocache(bus_addr, size);
-       if (!mem_base)
-               goto out;
-
-       dev->dma_mem = kmalloc(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 pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
-       int pos, err;
-
-       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);
-
 void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
                    enum dma_data_direction direction)
 {
index b6fa287..3d0f2b6 100644 (file)
@@ -30,6 +30,7 @@ config X86
        select HAVE_FTRACE
        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
        select HAVE_EFFICIENT_UNALIGNED_ACCESS
 
 config ARCH_DEFCONFIG
index 3754412..8dbffb8 100644 (file)
@@ -192,124 +192,6 @@ 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)
 {
        struct dma_mapping_ops *ops = get_dma_ops(dev);
@@ -379,7 +261,7 @@ 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) {
@@ -484,7 +366,7 @@ 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 (ops->unmap_single)
                ops->unmap_single(dev, bus, size, 0);
index f41335b..45329fc 100644 (file)
@@ -7,6 +7,8 @@
 
 #include <linux/scatterlist.h>
 
+#include <asm-generic/dma-coherent.h>
+
 /*
  * DMA-consistent mapping functions.  These allocate/free a region of
  * uncached, unwrite-buffered mapped memory space for use with DMA
index cb2fb25..da8ef8e 100644 (file)
@@ -14,6 +14,8 @@
 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
 
 #ifdef CONFIG_PCI
+#include <asm-generic/dma-coherent.h>
+
 void *dma_alloc_coherent(struct device *dev, size_t size,
                           dma_addr_t *dma_handle, gfp_t flag);
 
diff --git a/include/asm-generic/dma-coherent.h b/include/asm-generic/dma-coherent.h
new file mode 100644 (file)
index 0000000..85a3ffa
--- /dev/null
@@ -0,0 +1,32 @@
+#ifndef DMA_COHERENT_H
+#define DMA_COHERENT_H
+
+#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
+/*
+ * These two functions are only for dma allocator.
+ * Don't use them in device drivers.
+ */
+int dma_alloc_from_coherent(struct device *dev, ssize_t size,
+                                      dma_addr_t *dma_handle, void **ret);
+int dma_release_from_coherent(struct device *dev, int order, void *vaddr);
+
+/*
+ * Standard interface
+ */
+#define ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
+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);
+#else
+#define dma_alloc_from_coherent(dev, size, handle, ret) (0)
+#define dma_release_from_coherent(dev, order, vaddr) (0)
+#endif
+
+#endif
index 6c0b8a2..627315e 100644 (file)
@@ -5,6 +5,7 @@
 #include <linux/scatterlist.h>
 #include <asm/cacheflush.h>
 #include <asm/io.h>
+#include <asm-generic/dma-coherent.h>
 
 extern struct bus_type pci_bus_type;
 
index 0eaa9bf..ad9cd6d 100644 (file)
@@ -249,25 +249,5 @@ 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
index 43d6989..250e02c 100644 (file)
@@ -802,6 +802,10 @@ config PROC_PAGE_MONITOR
 
 endmenu                # General setup
 
+config HAVE_GENERIC_DMA_COHERENT
+       bool
+       default n
+
 config SLABINFO
        bool
        depends on PROC_FS
index 54f6983..4e1d7df 100644 (file)
@@ -84,6 +84,7 @@ obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
 obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
 obj-$(CONFIG_MARKERS) += marker.o
 obj-$(CONFIG_LATENCYTOP) += latencytop.o
+obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o
 obj-$(CONFIG_FTRACE) += trace/
 obj-$(CONFIG_TRACING) += trace/
 obj-$(CONFIG_SMP) += sched_cpupri.o
diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c
new file mode 100644 (file)
index 0000000..7517115
--- /dev/null
@@ -0,0 +1,154 @@
+/*
+ * 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;
+       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);
+
+/**
+ * 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 = 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);
+               } else if (mem->flags & DMA_MEMORY_EXCLUSIVE)
+                       *ret = NULL;
+       }
+       return (mem != NULL);
+}
+
+/**
+ * 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;
+}