The dma remap code only really makes sense for not cache coherent architectures, and currently is only used by arm, arm64 and xtensa. Split it out into a separate file with a separate Kconfig symbol, which gets the right copyright notice given that this code was written by Laura Abbott working for Code Aurora at that point.
Signed-off-by: Christoph Hellwig <[email protected]> Acked-by: Laura Abbott <[email protected]> --- arch/arm/Kconfig | 1 + arch/arm64/Kconfig | 1 + arch/csky/Kconfig | 1 + arch/xtensa/Kconfig | 1 + kernel/dma/Kconfig | 4 ++ kernel/dma/Makefile | 2 +- kernel/dma/mapping.c | 84 ------------------------------------------ kernel/dma/remap.c | 88 ++++++++++++++++++++++++++++++++++++++++++++ 8 files changed, 97 insertions(+), 85 deletions(-) create mode 100644 kernel/dma/remap.c diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 91be74d8df65..3b2852df6eb3 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -30,6 +30,7 @@ config ARM select CPU_PM if (SUSPEND || CPU_IDLE) select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS select DMA_DIRECT_OPS if !MMU + select DMA_REMAP if MMU select EDAC_SUPPORT select EDAC_ATOMIC_SCRUB select GENERIC_ALLOCATOR diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 787d7850e064..5d065acb6d10 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -82,6 +82,7 @@ config ARM64 select CRC32 select DCACHE_WORD_ACCESS select DMA_DIRECT_OPS + select DMA_REMAP select EDAC_SUPPORT select FRAME_POINTER select GENERIC_ALLOCATOR diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig index cb64f8dacd08..8a30e006a845 100644 --- a/arch/csky/Kconfig +++ b/arch/csky/Kconfig @@ -9,6 +9,7 @@ config CSKY select CLKSRC_OF select DMA_DIRECT_OPS select DMA_NONCOHERENT_OPS + select DMA_REMAP select IRQ_DOMAIN select HANDLE_DOMAIN_IRQ select DW_APB_TIMER_OF diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index d29b7365da8d..239bfb16c58b 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -11,6 +11,7 @@ config XTENSA select CLONE_BACKWARDS select COMMON_CLK select DMA_DIRECT_OPS + select DMA_REMAP if MMU select GENERIC_ATOMIC64 select GENERIC_CLOCKEVENTS select GENERIC_IRQ_SHOW diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig index 645c7a2ecde8..c92e08173ed8 100644 --- a/kernel/dma/Kconfig +++ b/kernel/dma/Kconfig @@ -51,3 +51,7 @@ config SWIOTLB bool select DMA_DIRECT_OPS select NEED_DMA_MAP_STATE + +config DMA_REMAP + depends on MMU + bool diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile index 7d581e4eea4a..f4feeceb8020 100644 --- a/kernel/dma/Makefile +++ b/kernel/dma/Makefile @@ -7,4 +7,4 @@ obj-$(CONFIG_DMA_DIRECT_OPS) += direct.o obj-$(CONFIG_DMA_VIRT_OPS) += virt.o obj-$(CONFIG_DMA_API_DEBUG) += debug.o obj-$(CONFIG_SWIOTLB) += swiotlb.o - +obj-$(CONFIG_DMA_REMAP) += remap.o diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 58dec7a92b7b..dfbc3deb95cd 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -262,87 +262,3 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, #endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */ } EXPORT_SYMBOL(dma_common_mmap); - -#ifdef CONFIG_MMU -static struct vm_struct *__dma_common_pages_remap(struct page **pages, - size_t size, unsigned long vm_flags, pgprot_t prot, - const void *caller) -{ - struct vm_struct *area; - - area = get_vm_area_caller(size, vm_flags, caller); - if (!area) - return NULL; - - if (map_vm_area(area, prot, pages)) { - vunmap(area->addr); - return NULL; - } - - return area; -} - -/* - * remaps an array of PAGE_SIZE pages into another vm_area - * Cannot be used in non-sleeping contexts - */ -void *dma_common_pages_remap(struct page **pages, size_t size, - unsigned long vm_flags, pgprot_t prot, - const void *caller) -{ - struct vm_struct *area; - - area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); - if (!area) - return NULL; - - area->pages = pages; - - return area->addr; -} - -/* - * remaps an allocated contiguous region into another vm_area. - * Cannot be used in non-sleeping contexts - */ - -void *dma_common_contiguous_remap(struct page *page, size_t size, - unsigned long vm_flags, - pgprot_t prot, const void *caller) -{ - int i; - struct page **pages; - struct vm_struct *area; - - pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL); - if (!pages) - return NULL; - - for (i = 0; i < (size >> PAGE_SHIFT); i++) - pages[i] = nth_page(page, i); - - area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); - - kfree(pages); - - if (!area) - return NULL; - return area->addr; -} - -/* - * unmaps a range previously mapped by dma_common_*_remap - */ -void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags) -{ - struct vm_struct *area = find_vm_area(cpu_addr); - - if (!area || (area->flags & vm_flags) != vm_flags) { - WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr); - return; - } - - unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size)); - vunmap(cpu_addr); -} -#endif diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c new file mode 100644 index 000000000000..456f7cc3414d --- /dev/null +++ b/kernel/dma/remap.c @@ -0,0 +1,88 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2014 The Linux Foundation + */ +#include <linux/dma-mapping.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +static struct vm_struct *__dma_common_pages_remap(struct page **pages, + size_t size, unsigned long vm_flags, pgprot_t prot, + const void *caller) +{ + struct vm_struct *area; + + area = get_vm_area_caller(size, vm_flags, caller); + if (!area) + return NULL; + + if (map_vm_area(area, prot, pages)) { + vunmap(area->addr); + return NULL; + } + + return area; +} + +/* + * remaps an array of PAGE_SIZE pages into another vm_area + * Cannot be used in non-sleeping contexts + */ +void *dma_common_pages_remap(struct page **pages, size_t size, + unsigned long vm_flags, pgprot_t prot, + const void *caller) +{ + struct vm_struct *area; + + area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); + if (!area) + return NULL; + + area->pages = pages; + + return area->addr; +} + +/* + * Remaps an allocated contiguous region into another vm_area. + * Cannot be used in non-sleeping contexts + */ +void *dma_common_contiguous_remap(struct page *page, size_t size, + unsigned long vm_flags, + pgprot_t prot, const void *caller) +{ + int i; + struct page **pages; + struct vm_struct *area; + + pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL); + if (!pages) + return NULL; + + for (i = 0; i < (size >> PAGE_SHIFT); i++) + pages[i] = nth_page(page, i); + + area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); + + kfree(pages); + + if (!area) + return NULL; + return area->addr; +} + +/* + * Unmaps a range previously mapped by dma_common_*_remap + */ +void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags) +{ + struct vm_struct *area = find_vm_area(cpu_addr); + + if (!area || (area->flags & vm_flags) != vm_flags) { + WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr); + return; + } + + unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size)); + vunmap(cpu_addr); +} -- 2.19.1 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
