IB/qib: Remove DMA mapping code

/*

 * 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

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 * 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;

		}

		sg->dma_address = addr + sg->offset;

#ifdef CONFIG_NEED_SG_DMA_LENGTH

		sg->dma_length = sg->length;

#endif

	}

	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 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,

	.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

};

	unsigned n, m;

	size_t off;

	/*

	 * We use RKEY == zero for kernel virtual addresses

	 * (see qib_get_dma_mr and qib_dma.c).

	 */

	/* We use RKEY == zero for kernel virtual addresses */

	rcu_read_lock();

	if (rkey == 0) {

		struct rvt_pd *pd = ibpd_to_rvtpd(qp->ibqp.pd);