diff options
Diffstat (limited to 'drivers/infiniband/hw/hfi1/dma.c')
| -rw-r--r-- | drivers/infiniband/hw/hfi1/dma.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/hfi1/dma.c b/drivers/infiniband/hw/hfi1/dma.c new file mode 100644 index 000000000000..7e8dab892848 --- /dev/null +++ b/drivers/infiniband/hw/hfi1/dma.c @@ -0,0 +1,183 @@ +/* + * Copyright(c) 2015, 2016 Intel Corporation. + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * BSD LICENSE + * + * 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. + * - Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ +#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 +}; |