[PATCH] Remove i386_ksyms.c, almost.
[linux-2.6.git] / arch / i386 / kernel / pci-dma.c
1 /*
2  * Dynamic DMA mapping support.
3  *
4  * On i386 there is no hardware dynamic DMA address translation,
5  * so consistent alloc/free are merely page allocation/freeing.
6  * The rest of the dynamic DMA mapping interface is implemented
7  * in asm/pci.h.
8  */
9
10 #include <linux/types.h>
11 #include <linux/mm.h>
12 #include <linux/string.h>
13 #include <linux/pci.h>
14 #include <linux/module.h>
15 #include <asm/io.h>
16
17 struct dma_coherent_mem {
18         void            *virt_base;
19         u32             device_base;
20         int             size;
21         int             flags;
22         unsigned long   *bitmap;
23 };
24
25 void *dma_alloc_coherent(struct device *dev, size_t size,
26                            dma_addr_t *dma_handle, unsigned int __nocast gfp)
27 {
28         void *ret;
29         struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
30         int order = get_order(size);
31         /* ignore region specifiers */
32         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
33
34         if (mem) {
35                 int page = bitmap_find_free_region(mem->bitmap, mem->size,
36                                                      order);
37                 if (page >= 0) {
38                         *dma_handle = mem->device_base + (page << PAGE_SHIFT);
39                         ret = mem->virt_base + (page << PAGE_SHIFT);
40                         memset(ret, 0, size);
41                         return ret;
42                 }
43                 if (mem->flags & DMA_MEMORY_EXCLUSIVE)
44                         return NULL;
45         }
46
47         if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
48                 gfp |= GFP_DMA;
49
50         ret = (void *)__get_free_pages(gfp, order);
51
52         if (ret != NULL) {
53                 memset(ret, 0, size);
54                 *dma_handle = virt_to_phys(ret);
55         }
56         return ret;
57 }
58 EXPORT_SYMBOL(dma_alloc_coherent);
59
60 void dma_free_coherent(struct device *dev, size_t size,
61                          void *vaddr, dma_addr_t dma_handle)
62 {
63         struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
64         int order = get_order(size);
65         
66         if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) {
67                 int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
68
69                 bitmap_release_region(mem->bitmap, page, order);
70         } else
71                 free_pages((unsigned long)vaddr, order);
72 }
73 EXPORT_SYMBOL(dma_free_coherent);
74
75 int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
76                                 dma_addr_t device_addr, size_t size, int flags)
77 {
78         void __iomem *mem_base;
79         int pages = size >> PAGE_SHIFT;
80         int bitmap_size = (pages + 31)/32;
81
82         if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
83                 goto out;
84         if (!size)
85                 goto out;
86         if (dev->dma_mem)
87                 goto out;
88
89         /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
90
91         mem_base = ioremap(bus_addr, size);
92         if (!mem_base)
93                 goto out;
94
95         dev->dma_mem = kmalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
96         if (!dev->dma_mem)
97                 goto out;
98         memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem));
99         dev->dma_mem->bitmap = kmalloc(bitmap_size, GFP_KERNEL);
100         if (!dev->dma_mem->bitmap)
101                 goto free1_out;
102         memset(dev->dma_mem->bitmap, 0, bitmap_size);
103
104         dev->dma_mem->virt_base = mem_base;
105         dev->dma_mem->device_base = device_addr;
106         dev->dma_mem->size = pages;
107         dev->dma_mem->flags = flags;
108
109         if (flags & DMA_MEMORY_MAP)
110                 return DMA_MEMORY_MAP;
111
112         return DMA_MEMORY_IO;
113
114  free1_out:
115         kfree(dev->dma_mem->bitmap);
116  out:
117         return 0;
118 }
119 EXPORT_SYMBOL(dma_declare_coherent_memory);
120
121 void dma_release_declared_memory(struct device *dev)
122 {
123         struct dma_coherent_mem *mem = dev->dma_mem;
124         
125         if(!mem)
126                 return;
127         dev->dma_mem = NULL;
128         iounmap(mem->virt_base);
129         kfree(mem->bitmap);
130         kfree(mem);
131 }
132 EXPORT_SYMBOL(dma_release_declared_memory);
133
134 void *dma_mark_declared_memory_occupied(struct device *dev,
135                                         dma_addr_t device_addr, size_t size)
136 {
137         struct dma_coherent_mem *mem = dev->dma_mem;
138         int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
139         int pos, err;
140
141         if (!mem)
142                 return ERR_PTR(-EINVAL);
143
144         pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
145         err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages));
146         if (err != 0)
147                 return ERR_PTR(err);
148         return mem->virt_base + (pos << PAGE_SHIFT);
149 }
150 EXPORT_SYMBOL(dma_mark_declared_memory_occupied);