diff options
Diffstat (limited to 'drivers/infiniband/hw/qib/qib_dma.c')
| -rw-r--r-- | drivers/infiniband/hw/qib/qib_dma.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/drivers/infiniband/hw/qib/qib_dma.c b/drivers/infiniband/hw/qib/qib_dma.c new file mode 100644 index 000000000000..2920bb39a65b --- /dev/null +++ b/drivers/infiniband/hw/qib/qib_dma.c @@ -0,0 +1,182 @@ +/* + * 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 +}; |