IB/hf1: Remove DMA mapping code

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 * Copyright(c) 2015, 2016 Intel Corporation.

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#include <linux/types.h>

#include <linux/scatterlist.h>

#include "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 hfi1_mapping_error(struct ib_device *dev, u64 dma_addr)

{

	return dma_addr == BAD_DMA_ADDRESS;

}

static u64 hfi1_dma_map_single(struct ib_device *dev, void *cpu_addr,

			       size_t size, enum dma_data_direction direction)

{

	if (WARN_ON(!valid_dma_direction(direction)))

		return BAD_DMA_ADDRESS;

	return (u64)cpu_addr;

}

static void hfi1_dma_unmap_single(struct ib_device *dev, u64 addr, size_t size,

				  enum dma_data_direction direction)

{

	/* This is a stub, nothing to be done here */

}

static u64 hfi1_dma_map_page(struct ib_device *dev, struct page *page,

			     unsigned long offset, size_t size,

			    enum dma_data_direction direction)

{

	u64 addr;

	if (WARN_ON(!valid_dma_direction(direction)))

		return BAD_DMA_ADDRESS;

	if (offset + size > PAGE_SIZE)

		return BAD_DMA_ADDRESS;

	addr = (u64)page_address(page);

	if (addr)

		addr += offset;

	return addr;

}

static void hfi1_dma_unmap_page(struct ib_device *dev, u64 addr, size_t size,

				enum dma_data_direction direction)

{

	/* This is a stub, nothing to be done here */

}

static int hfi1_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;

	if (WARN_ON(!valid_dma_direction(direction)))

		return BAD_DMA_ADDRESS;

	for_each_sg(sgl, sg, nents, i) {

		addr = (u64)page_address(sg_page(sg));

		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 hfi1_unmap_sg(struct ib_device *dev,

			  struct scatterlist *sg, int nents,

			 enum dma_data_direction direction)

{

	/* This is a stub, nothing to be done here */

}

static void hfi1_sync_single_for_cpu(struct ib_device *dev, u64 addr,

				     size_t size, enum dma_data_direction dir)

{

}

static void hfi1_sync_single_for_device(struct ib_device *dev, u64 addr,

					size_t size,

					enum dma_data_direction dir)

{

}

static void *hfi1_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 hfi1_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 hfi1_dma_mapping_ops = {

	.mapping_error = hfi1_mapping_error,

	.map_single = hfi1_dma_map_single,

	.unmap_single = hfi1_dma_unmap_single,

	.map_page = hfi1_dma_map_page,

	.unmap_page = hfi1_dma_unmap_page,

	.map_sg = hfi1_map_sg,

	.unmap_sg = hfi1_unmap_sg,

	.sync_single_for_cpu = hfi1_sync_single_for_cpu,

	.sync_single_for_device = hfi1_sync_single_for_device,

	.alloc_coherent = hfi1_dma_alloc_coherent,

	.free_coherent = hfi1_dma_free_coherent

};