From 0eb3b4ab762df44f2cff982ddb8f42b3085f4e52 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 20 Oct 2020 09:33:07 +0200 Subject: ARM/sa1111: add a missing include of dma-map-ops.h Ensure the dmabounce functions are available for all Kconfig permutations. Fixes: 0a0f0d8be76d ("dma-mapping: split ") Reported-by: kernel test robot Signed-off-by: Christoph Hellwig --- arch/arm/common/sa1111.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/common/sa1111.c b/arch/arm/common/sa1111.c index c98ebae1aeac..f89c1ea327a2 100644 --- a/arch/arm/common/sa1111.c +++ b/arch/arm/common/sa1111.c @@ -22,7 +22,7 @@ #include #include #include -#include +#include #include #include -- cgit From 695cebe58dcf3d9802cdfa9c327b5c7641a5914b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 20 Oct 2020 10:41:07 +0200 Subject: dma-mapping: move more functions to dma-map-ops.h Due to a mismerge a bunch of prototypes that should have moved to dma-map-ops.h are still in dma-mapping.h, fix that up. Signed-off-by: Christoph Hellwig --- include/linux/dma-map-ops.h | 23 +++++++++++++++++++++++ include/linux/dma-mapping.h | 24 ------------------------ kernel/dma/remap.c | 2 +- 3 files changed, 24 insertions(+), 25 deletions(-) diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index 8029f7e04145..a5f89fc4d6df 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -203,6 +203,29 @@ static inline int dma_mmap_from_global_coherent(struct vm_area_struct *vma, } #endif /* CONFIG_DMA_DECLARE_COHERENT */ +int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs); +int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs); +struct page *dma_common_alloc_pages(struct device *dev, size_t size, + dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); +void dma_common_free_pages(struct device *dev, size_t size, struct page *vaddr, + dma_addr_t dma_handle, enum dma_data_direction dir); + +struct page **dma_common_find_pages(void *cpu_addr); +void *dma_common_contiguous_remap(struct page *page, size_t size, pgprot_t prot, + const void *caller); +void *dma_common_pages_remap(struct page **pages, size_t size, pgprot_t prot, + const void *caller); +void dma_common_free_remap(void *cpu_addr, size_t size); + +struct page *dma_alloc_from_pool(struct device *dev, size_t size, + void **cpu_addr, gfp_t flags, + bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)); +bool dma_free_from_pool(struct device *dev, void *start, size_t size); + #ifdef CONFIG_ARCH_HAS_DMA_COHERENCE_H #include #elif defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 3f029afdc9dc..956151052d45 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -389,30 +389,6 @@ static inline void dma_sync_sgtable_for_device(struct device *dev, #define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0) #define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0) -extern int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, - void *cpu_addr, dma_addr_t dma_addr, size_t size, - unsigned long attrs); -struct page *dma_common_alloc_pages(struct device *dev, size_t size, - dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); -void dma_common_free_pages(struct device *dev, size_t size, struct page *vaddr, - dma_addr_t dma_handle, enum dma_data_direction dir); -struct page **dma_common_find_pages(void *cpu_addr); -void *dma_common_contiguous_remap(struct page *page, size_t size, - pgprot_t prot, const void *caller); - -void *dma_common_pages_remap(struct page **pages, size_t size, - pgprot_t prot, const void *caller); -void dma_common_free_remap(void *cpu_addr, size_t size); - -struct page *dma_alloc_from_pool(struct device *dev, size_t size, - void **cpu_addr, gfp_t flags, - bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)); -bool dma_free_from_pool(struct device *dev, void *start, size_t size); - -int -dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, void *cpu_addr, - dma_addr_t dma_addr, size_t size, unsigned long attrs); - static inline void *dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp) { diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c index 78b23f089cf1..905c3fa005f1 100644 --- a/kernel/dma/remap.c +++ b/kernel/dma/remap.c @@ -2,7 +2,7 @@ /* * Copyright (c) 2014 The Linux Foundation */ -#include +#include #include #include -- cgit From 6857a5ebaabc5b9d989872700b4b71dd2a6d6453 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 26 Sep 2020 16:11:03 +0200 Subject: dma-mapping: document dma_{alloc,free}_pages Document the new dma_alloc_pages and dma_free_pages APIs, and fix up the documentation for dma_alloc_noncoherent and dma_free_noncoherent. Reported-by: Robin Murphy Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- Documentation/core-api/dma-api.rst | 49 +++++++++++++++++++++++++++++++++----- 1 file changed, 43 insertions(+), 6 deletions(-) diff --git a/Documentation/core-api/dma-api.rst b/Documentation/core-api/dma-api.rst index ea0413276ddb..75cb757bbff0 100644 --- a/Documentation/core-api/dma-api.rst +++ b/Documentation/core-api/dma-api.rst @@ -519,10 +519,9 @@ routines, e.g.::: Part II - Non-coherent DMA allocations -------------------------------------- -These APIs allow to allocate pages in the kernel direct mapping that are -guaranteed to be DMA addressable. This means that unlike dma_alloc_coherent, -virt_to_page can be called on the resulting address, and the resulting -struct page can be used for everything a struct page is suitable for. +These APIs allow to allocate pages that are guaranteed to be DMA addressable +by the passed in device, but which need explicit management of memory ownership +for the kernel vs the device. If you don't understand how cache line coherency works between a processor and an I/O device, you should not be using this part of the API. @@ -537,7 +536,7 @@ an I/O device, you should not be using this part of the API. This routine allocates a region of bytes of consistent memory. It returns a pointer to the allocated region (in the processor's virtual address space) or NULL if the allocation failed. The returned memory may or may not -be in the kernels direct mapping. Drivers must not call virt_to_page on +be in the kernel direct mapping. Drivers must not call virt_to_page on the returned memory region. It also returns a which may be cast to an unsigned integer the @@ -565,7 +564,45 @@ reused. Free a region of memory previously allocated using dma_alloc_noncoherent(). dev, size and dma_handle and dir must all be the same as those passed into dma_alloc_noncoherent(). cpu_addr must be the virtual address returned by -the dma_alloc_noncoherent(). +dma_alloc_noncoherent(). + +:: + + struct page * + dma_alloc_pages(struct device *dev, size_t size, dma_addr_t *dma_handle, + enum dma_data_direction dir, gfp_t gfp) + +This routine allocates a region of bytes of non-coherent memory. It +returns a pointer to first struct page for the region, or NULL if the +allocation failed. The resulting struct page can be used for everything a +struct page is suitable for. + +It also returns a which may be cast to an unsigned integer the +same width as the bus and given to the device as the DMA address base of +the region. + +The dir parameter specified if data is read and/or written by the device, +see dma_map_single() for details. + +The gfp parameter allows the caller to specify the ``GFP_`` flags (see +kmalloc()) for the allocation, but rejects flags used to specify a memory +zone such as GFP_DMA or GFP_HIGHMEM. + +Before giving the memory to the device, dma_sync_single_for_device() needs +to be called, and before reading memory written by the device, +dma_sync_single_for_cpu(), just like for streaming DMA mappings that are +reused. + +:: + + void + dma_free_pages(struct device *dev, size_t size, struct page *page, + dma_addr_t dma_handle, enum dma_data_direction dir) + +Free a region of memory previously allocated using dma_alloc_pages(). +dev, size and dma_handle and dir must all be the same as those passed into +dma_alloc_noncoherent(). page must be the pointer returned by +dma_alloc_pages(). :: -- cgit