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+/*
+ * Copyright (c) 2006, 2009, 2010 QLogic, Corporation. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include <linux/types.h>
+#include <linux/scatterlist.h>
+
+#include "qib_verbs.h"
+
+#define BAD_DMA_ADDRESS ((u64) 0)
+
+/*
+ * The following functions implement driver specific replacements
+ * for the ib_dma_*() functions.
+ *
+ * These functions return kernel virtual addresses instead of
+ * device bus addresses since the driver uses the CPU to copy
+ * data instead of using hardware DMA.
+ */
+
+static int qib_mapping_error(struct ib_device *dev, u64 dma_addr)
+{
+ return dma_addr == BAD_DMA_ADDRESS;
+}
+
+static u64 qib_dma_map_single(struct ib_device *dev, void *cpu_addr,
+ size_t size, enum dma_data_direction direction)
+{
+ BUG_ON(!valid_dma_direction(direction));
+ return (u64) cpu_addr;
+}
+
+static void qib_dma_unmap_single(struct ib_device *dev, u64 addr, size_t size,
+ enum dma_data_direction direction)
+{
+ BUG_ON(!valid_dma_direction(direction));
+}
+
+static u64 qib_dma_map_page(struct ib_device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction direction)
+{
+ u64 addr;
+
+ BUG_ON(!valid_dma_direction(direction));
+
+ if (offset + size > PAGE_SIZE) {
+ addr = BAD_DMA_ADDRESS;
+ goto done;
+ }
+
+ addr = (u64) page_address(page);
+ if (addr)
+ addr += offset;
+ /* TODO: handle highmem pages */
+
+done:
+ return addr;
+}
+
+static void qib_dma_unmap_page(struct ib_device *dev, u64 addr, size_t size,
+ enum dma_data_direction direction)
+{
+ BUG_ON(!valid_dma_direction(direction));
+}
+
+static int qib_map_sg(struct ib_device *dev, struct scatterlist *sgl,
+ int nents, enum dma_data_direction direction)
+{
+ struct scatterlist *sg;
+ u64 addr;
+ int i;
+ int ret = nents;
+
+ BUG_ON(!valid_dma_direction(direction));
+
+ for_each_sg(sgl, sg, nents, i) {
+ addr = (u64) page_address(sg_page(sg));
+ /* TODO: handle highmem pages */
+ if (!addr) {
+ ret = 0;
+ break;
+ }
+ }
+ return ret;
+}
+
+static void qib_unmap_sg(struct ib_device *dev,
+ struct scatterlist *sg, int nents,
+ enum dma_data_direction direction)
+{
+ BUG_ON(!valid_dma_direction(direction));
+}
+
+static u64 qib_sg_dma_address(struct ib_device *dev, struct scatterlist *sg)
+{
+ u64 addr = (u64) page_address(sg_page(sg));
+
+ if (addr)
+ addr += sg->offset;
+ return addr;
+}
+
+static unsigned int qib_sg_dma_len(struct ib_device *dev,
+ struct scatterlist *sg)
+{
+ return sg->length;
+}
+
+static void qib_sync_single_for_cpu(struct ib_device *dev, u64 addr,
+ size_t size, enum dma_data_direction dir)
+{
+}
+
+static void qib_sync_single_for_device(struct ib_device *dev, u64 addr,
+ size_t size,
+ enum dma_data_direction dir)
+{
+}
+
+static void *qib_dma_alloc_coherent(struct ib_device *dev, size_t size,
+ u64 *dma_handle, gfp_t flag)
+{
+ struct page *p;
+ void *addr = NULL;
+
+ p = alloc_pages(flag, get_order(size));
+ if (p)
+ addr = page_address(p);
+ if (dma_handle)
+ *dma_handle = (u64) addr;
+ return addr;
+}
+
+static void qib_dma_free_coherent(struct ib_device *dev, size_t size,
+ void *cpu_addr, u64 dma_handle)
+{
+ free_pages((unsigned long) cpu_addr, get_order(size));
+}
+
+struct ib_dma_mapping_ops qib_dma_mapping_ops = {
+ .mapping_error = qib_mapping_error,
+ .map_single = qib_dma_map_single,
+ .unmap_single = qib_dma_unmap_single,
+ .map_page = qib_dma_map_page,
+ .unmap_page = qib_dma_unmap_page,
+ .map_sg = qib_map_sg,
+ .unmap_sg = qib_unmap_sg,
+ .dma_address = qib_sg_dma_address,
+ .dma_len = qib_sg_dma_len,
+ .sync_single_for_cpu = qib_sync_single_for_cpu,
+ .sync_single_for_device = qib_sync_single_for_device,
+ .alloc_coherent = qib_dma_alloc_coherent,
+ .free_coherent = qib_dma_free_coherent
+};