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author | Jason Gunthorpe <jgg@mellanox.com> | 2018-08-16 13:08:18 -0600 |
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committer | Jason Gunthorpe <jgg@mellanox.com> | 2018-08-16 13:12:00 -0600 |
commit | 89982f7ccee2fcd8fea7936b81eec6defbf0f131 (patch) | |
tree | fc553c8d008d24595ad7de0ea0f3b56f656da27c /kernel/dma/virt.c | |
parent | a1ceeca679dccc492235f0f629d9e9f7b3d51ca8 (diff) | |
parent | 94710cac0ef4ee177a63b5227664b38c95bbf703 (diff) | |
download | linux-89982f7ccee2fcd8fea7936b81eec6defbf0f131.tar.gz linux-89982f7ccee2fcd8fea7936b81eec6defbf0f131.tar.bz2 linux-89982f7ccee2fcd8fea7936b81eec6defbf0f131.zip |
Merge tag 'v4.18' into rdma.git for-next
Resolve merge conflicts from the -rc cycle against the rdma.git tree:
Conflicts:
drivers/infiniband/core/uverbs_cmd.c
- New ifs added to ib_uverbs_ex_create_flow in -rc and for-next
- Merge removal of file->ucontext in for-next with new code in -rc
drivers/infiniband/core/uverbs_main.c
- for-next removed code from ib_uverbs_write() that was modified
in for-rc
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'kernel/dma/virt.c')
-rw-r--r-- | kernel/dma/virt.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/kernel/dma/virt.c b/kernel/dma/virt.c new file mode 100644 index 000000000000..631ddec4b60a --- /dev/null +++ b/kernel/dma/virt.c @@ -0,0 +1,59 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMA operations that map to virtual addresses without flushing memory. + */ +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/dma-mapping.h> +#include <linux/scatterlist.h> + +static void *dma_virt_alloc(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + unsigned long attrs) +{ + void *ret; + + ret = (void *)__get_free_pages(gfp, get_order(size)); + if (ret) + *dma_handle = (uintptr_t)ret; + return ret; +} + +static void dma_virt_free(struct device *dev, size_t size, + void *cpu_addr, dma_addr_t dma_addr, + unsigned long attrs) +{ + free_pages((unsigned long)cpu_addr, get_order(size)); +} + +static dma_addr_t dma_virt_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + return (uintptr_t)(page_address(page) + offset); +} + +static int dma_virt_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, + unsigned long attrs) +{ + int i; + struct scatterlist *sg; + + for_each_sg(sgl, sg, nents, i) { + BUG_ON(!sg_page(sg)); + sg_dma_address(sg) = (uintptr_t)sg_virt(sg); + sg_dma_len(sg) = sg->length; + } + + return nents; +} + +const struct dma_map_ops dma_virt_ops = { + .alloc = dma_virt_alloc, + .free = dma_virt_free, + .map_page = dma_virt_map_page, + .map_sg = dma_virt_map_sg, +}; +EXPORT_SYMBOL(dma_virt_ops); |