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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-20 09:30:01 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-20 09:30:01 +0200 |
commit | 6d90eb7ba341b3eb035121eff0b69d370cbc251e (patch) | |
tree | 332809825f5aab97e839ab4534e5b81fb28e0c84 /kernel/dma/noncoherent.c | |
parent | proc: fix missing final NUL in get_mm_cmdline() rewrite (diff) | |
parent | dma-mapping: move all DMA mapping code to kernel/dma (diff) | |
download | linux-6d90eb7ba341b3eb035121eff0b69d370cbc251e.tar.xz linux-6d90eb7ba341b3eb035121eff0b69d370cbc251e.zip |
Merge tag 'dma-rename-4.18' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping rename from Christoph Hellwig:
"Move all the dma-mapping code to kernel/dma and lose their dma-*
prefixes"
* tag 'dma-rename-4.18' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: move all DMA mapping code to kernel/dma
dma-mapping: use obj-y instead of lib-y for generic dma ops
Diffstat (limited to 'kernel/dma/noncoherent.c')
-rw-r--r-- | kernel/dma/noncoherent.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/kernel/dma/noncoherent.c b/kernel/dma/noncoherent.c new file mode 100644 index 000000000000..79e9a757387f --- /dev/null +++ b/kernel/dma/noncoherent.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Christoph Hellwig. + * + * DMA operations that map physical memory directly without providing cache + * coherence. + */ +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/dma-direct.h> +#include <linux/dma-noncoherent.h> +#include <linux/scatterlist.h> + +static void dma_noncoherent_sync_single_for_device(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir) +{ + arch_sync_dma_for_device(dev, dma_to_phys(dev, addr), size, dir); +} + +static void dma_noncoherent_sync_sg_for_device(struct device *dev, + struct scatterlist *sgl, int nents, enum dma_data_direction dir) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgl, sg, nents, i) + arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir); +} + +static dma_addr_t dma_noncoherent_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + dma_addr_t addr; + + addr = dma_direct_map_page(dev, page, offset, size, dir, attrs); + if (!dma_mapping_error(dev, addr) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + arch_sync_dma_for_device(dev, page_to_phys(page) + offset, + size, dir); + return addr; +} + +static int dma_noncoherent_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + nents = dma_direct_map_sg(dev, sgl, nents, dir, attrs); + if (nents > 0 && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_noncoherent_sync_sg_for_device(dev, sgl, nents, dir); + return nents; +} + +#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU +static void dma_noncoherent_sync_single_for_cpu(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir) +{ + arch_sync_dma_for_cpu(dev, dma_to_phys(dev, addr), size, dir); +} + +static void dma_noncoherent_sync_sg_for_cpu(struct device *dev, + struct scatterlist *sgl, int nents, enum dma_data_direction dir) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgl, sg, nents, i) + arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir); +} + +static void dma_noncoherent_unmap_page(struct device *dev, dma_addr_t addr, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_noncoherent_sync_single_for_cpu(dev, addr, size, dir); +} + +static void dma_noncoherent_unmap_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_noncoherent_sync_sg_for_cpu(dev, sgl, nents, dir); +} +#endif + +const struct dma_map_ops dma_noncoherent_ops = { + .alloc = arch_dma_alloc, + .free = arch_dma_free, + .mmap = arch_dma_mmap, + .sync_single_for_device = dma_noncoherent_sync_single_for_device, + .sync_sg_for_device = dma_noncoherent_sync_sg_for_device, + .map_page = dma_noncoherent_map_page, + .map_sg = dma_noncoherent_map_sg, +#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU + .sync_single_for_cpu = dma_noncoherent_sync_single_for_cpu, + .sync_sg_for_cpu = dma_noncoherent_sync_sg_for_cpu, + .unmap_page = dma_noncoherent_unmap_page, + .unmap_sg = dma_noncoherent_unmap_sg, +#endif + .dma_supported = dma_direct_supported, + .mapping_error = dma_direct_mapping_error, + .cache_sync = arch_dma_cache_sync, +}; +EXPORT_SYMBOL(dma_noncoherent_ops); |