ia64/linux-2.6.18-xen.hg

view arch/m68k/kernel/dma.c @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 831230e53067
children
line source
1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file COPYING in the main directory of this archive
4 * for more details.
5 */
7 #undef DEBUG
9 #include <linux/dma-mapping.h>
10 #include <linux/device.h>
11 #include <linux/kernel.h>
12 #include <linux/vmalloc.h>
14 #include <asm/pgalloc.h>
15 #include <asm/scatterlist.h>
17 void *dma_alloc_coherent(struct device *dev, size_t size,
18 dma_addr_t *handle, int flag)
19 {
20 struct page *page, **map;
21 pgprot_t pgprot;
22 void *addr;
23 int i, order;
25 pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);
27 size = PAGE_ALIGN(size);
28 order = get_order(size);
30 page = alloc_pages(flag, order);
31 if (!page)
32 return NULL;
34 *handle = page_to_phys(page);
35 map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
36 if (!map) {
37 __free_pages(page, order);
38 return NULL;
39 }
40 split_page(page, order);
42 order = 1 << order;
43 size >>= PAGE_SHIFT;
44 map[0] = page;
45 for (i = 1; i < size; i++)
46 map[i] = page + i;
47 for (; i < order; i++)
48 __free_page(page + i);
49 pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
50 if (CPU_IS_040_OR_060)
51 pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
52 else
53 pgprot_val(pgprot) |= _PAGE_NOCACHE030;
54 addr = vmap(map, size, flag, pgprot);
55 kfree(map);
57 return addr;
58 }
59 EXPORT_SYMBOL(dma_alloc_coherent);
61 void dma_free_coherent(struct device *dev, size_t size,
62 void *addr, dma_addr_t handle)
63 {
64 pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
65 vfree(addr);
66 }
67 EXPORT_SYMBOL(dma_free_coherent);
69 inline void dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size,
70 enum dma_data_direction dir)
71 {
72 switch (dir) {
73 case DMA_TO_DEVICE:
74 cache_push(handle, size);
75 break;
76 case DMA_FROM_DEVICE:
77 cache_clear(handle, size);
78 break;
79 default:
80 if (printk_ratelimit())
81 printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
82 break;
83 }
84 }
85 EXPORT_SYMBOL(dma_sync_single_for_device);
87 void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
88 enum dma_data_direction dir)
89 {
90 int i;
92 for (i = 0; i < nents; sg++, i++)
93 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
94 }
95 EXPORT_SYMBOL(dma_sync_sg_for_device);
97 dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
98 enum dma_data_direction dir)
99 {
100 dma_addr_t handle = virt_to_bus(addr);
102 dma_sync_single_for_device(dev, handle, size, dir);
103 return handle;
104 }
105 EXPORT_SYMBOL(dma_map_single);
107 dma_addr_t dma_map_page(struct device *dev, struct page *page,
108 unsigned long offset, size_t size,
109 enum dma_data_direction dir)
110 {
111 dma_addr_t handle = page_to_phys(page) + offset;
113 dma_sync_single_for_device(dev, handle, size, dir);
114 return handle;
115 }
116 EXPORT_SYMBOL(dma_map_page);
118 int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
119 enum dma_data_direction dir)
120 {
121 int i;
123 for (i = 0; i < nents; sg++, i++) {
124 sg->dma_address = page_to_phys(sg->page) + sg->offset;
125 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
126 }
127 return nents;
128 }
129 EXPORT_SYMBOL(dma_map_sg);