vserver 1.9.3

[linux-2.6.git] / arch / i386 / kernel / pci-dma.c

diff --git a/arch/i386/kernel/pci-dma.c b/arch/i386/kernel/pci-dma.c
index 10dc6b7..982fe8c 100644 (file)
--- a/arch/i386/kernel/pci-dma.c
+++ b/arch/i386/kernel/pci-dma.c
@@ -13,17 +13,40 @@
 #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, int 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 (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
                gfp |= GFP_DMA;
 
-       ret = (void *)__get_free_pages(gfp, get_order(size));
+       ret = (void *)__get_free_pages(gfp, order);
 
        if (ret != NULL) {
                memset(ret, 0, size);
@@ -35,5 +58,89 @@ 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)
 {
-       free_pages((unsigned long)vaddr, get_order(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
+               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 = (pages + 31)/32;
+
+       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 = kmalloc(GFP_KERNEL, sizeof(struct dma_coherent_mem));
+       if (!dev->dma_mem)
+               goto out;
+       memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem));
+       dev->dma_mem->bitmap = kmalloc(GFP_KERNEL, bitmap_size);
+       if (!dev->dma_mem->bitmap)
+               goto free1_out;
+       memset(dev->dma_mem->bitmap, 0, bitmap_size);
+
+       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->bitmap);
+ 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;
+       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);