2 * Copyright (c) 2006 QLogic, Corporation. All rights reserved.
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33 #include <linux/scatterlist.h>
34 #include <linux/gfp.h>
35 #include <rdma/ib_verbs.h>
37 #include "ipath_verbs.h"
39 #define BAD_DMA_ADDRESS ((u64) 0)
42 * The following functions implement driver specific replacements
43 * for the ib_dma_*() functions.
45 * These functions return kernel virtual addresses instead of
46 * device bus addresses since the driver uses the CPU to copy
47 * data instead of using hardware DMA.
50 static int ipath_mapping_error(struct ib_device *dev, u64 dma_addr)
52 return dma_addr == BAD_DMA_ADDRESS;
55 static u64 ipath_dma_map_single(struct ib_device *dev,
56 void *cpu_addr, size_t size,
57 enum dma_data_direction direction)
59 BUG_ON(!valid_dma_direction(direction));
60 return (u64) cpu_addr;
63 static void ipath_dma_unmap_single(struct ib_device *dev,
64 u64 addr, size_t size,
65 enum dma_data_direction direction)
67 BUG_ON(!valid_dma_direction(direction));
70 static u64 ipath_dma_map_page(struct ib_device *dev,
74 enum dma_data_direction direction)
78 BUG_ON(!valid_dma_direction(direction));
80 if (offset + size > PAGE_SIZE) {
81 addr = BAD_DMA_ADDRESS;
85 addr = (u64) page_address(page);
88 /* TODO: handle highmem pages */
94 static void ipath_dma_unmap_page(struct ib_device *dev,
95 u64 addr, size_t size,
96 enum dma_data_direction direction)
98 BUG_ON(!valid_dma_direction(direction));
101 static int ipath_map_sg(struct ib_device *dev, struct scatterlist *sgl,
102 int nents, enum dma_data_direction direction)
104 struct scatterlist *sg;
109 BUG_ON(!valid_dma_direction(direction));
111 for_each_sg(sgl, sg, nents, i) {
112 addr = (u64) page_address(sg_page(sg));
113 /* TODO: handle highmem pages */
122 static void ipath_unmap_sg(struct ib_device *dev,
123 struct scatterlist *sg, int nents,
124 enum dma_data_direction direction)
126 BUG_ON(!valid_dma_direction(direction));
129 static u64 ipath_sg_dma_address(struct ib_device *dev, struct scatterlist *sg)
131 u64 addr = (u64) page_address(sg_page(sg));
138 static unsigned int ipath_sg_dma_len(struct ib_device *dev,
139 struct scatterlist *sg)
144 static void ipath_sync_single_for_cpu(struct ib_device *dev,
147 enum dma_data_direction dir)
151 static void ipath_sync_single_for_device(struct ib_device *dev,
154 enum dma_data_direction dir)
158 static void *ipath_dma_alloc_coherent(struct ib_device *dev, size_t size,
159 u64 *dma_handle, gfp_t flag)
164 p = alloc_pages(flag, get_order(size));
166 addr = page_address(p);
168 *dma_handle = (u64) addr;
172 static void ipath_dma_free_coherent(struct ib_device *dev, size_t size,
173 void *cpu_addr, u64 dma_handle)
175 free_pages((unsigned long) cpu_addr, get_order(size));
178 struct ib_dma_mapping_ops ipath_dma_mapping_ops = {
180 ipath_dma_map_single,
181 ipath_dma_unmap_single,
183 ipath_dma_unmap_page,
186 ipath_sg_dma_address,
188 ipath_sync_single_for_cpu,
189 ipath_sync_single_for_device,
190 ipath_dma_alloc_coherent,
191 ipath_dma_free_coherent