From 4f8232bbf887123f78bcdca3dfd2b3dfa52a0112 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 21 Feb 2020 12:24:02 -0800 Subject: dma-direct: remove the cached_kernel_address hook dma-direct now finds the kernel address for coherent allocations based on the dma address, so the cached_kernel_address hooks is unused and can be removed entirely. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- arch/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/Kconfig') diff --git a/arch/Kconfig b/arch/Kconfig index 98de654b79b3..7994b239f155 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -249,7 +249,7 @@ config ARCH_HAS_SET_DIRECT_MAP # # Select if arch has an uncached kernel segment and provides the -# uncached_kernel_address / cached_kernel_address symbols to use it +# uncached_kernel_address symbol to use it # config ARCH_HAS_UNCACHED_SEGMENT select ARCH_HAS_DMA_PREP_COHERENT -- cgit v1.2.3-58-ga151 From fa7e2247c5729f990c7456fe09f3af99c8f2571b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 21 Feb 2020 15:55:43 -0800 Subject: dma-direct: make uncached_kernel_address more general Rename the symbol to arch_dma_set_uncached, and pass a size to it as well as allow an error return. That will allow reusing this hook for in-place pagetable remapping. As the in-place remap doesn't always require an explicit cache flush, also detangle ARCH_HAS_DMA_PREP_COHERENT from ARCH_HAS_DMA_SET_UNCACHED. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- arch/Kconfig | 8 ++++---- arch/microblaze/Kconfig | 2 +- arch/microblaze/mm/consistent.c | 2 +- arch/mips/Kconfig | 3 ++- arch/mips/mm/dma-noncoherent.c | 2 +- arch/nios2/Kconfig | 3 ++- arch/nios2/mm/dma-mapping.c | 2 +- arch/xtensa/Kconfig | 2 +- arch/xtensa/kernel/pci-dma.c | 2 +- include/linux/dma-noncoherent.h | 2 +- kernel/dma/direct.c | 10 ++++++---- 11 files changed, 21 insertions(+), 17 deletions(-) (limited to 'arch/Kconfig') diff --git a/arch/Kconfig b/arch/Kconfig index 7994b239f155..090cfe0c82a7 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -248,11 +248,11 @@ config ARCH_HAS_SET_DIRECT_MAP bool # -# Select if arch has an uncached kernel segment and provides the -# uncached_kernel_address symbol to use it +# Select if the architecture provides the arch_dma_set_uncached symbol to +# either provide an uncached segement alias for a DMA allocation, or +# to remap the page tables in place. # -config ARCH_HAS_UNCACHED_SEGMENT - select ARCH_HAS_DMA_PREP_COHERENT +config ARCH_HAS_DMA_SET_UNCACHED bool # Select if arch init_task must go in the __init_task_data section diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig index 6a331bd57ea8..9606c244b5b8 100644 --- a/arch/microblaze/Kconfig +++ b/arch/microblaze/Kconfig @@ -8,7 +8,7 @@ config MICROBLAZE select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_HAS_SYNC_DMA_FOR_CPU select ARCH_HAS_SYNC_DMA_FOR_DEVICE - select ARCH_HAS_UNCACHED_SEGMENT if !MMU + select ARCH_HAS_DMA_SET_UNCACHED if !MMU select ARCH_MIGHT_HAVE_PC_PARPORT select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_TABLE_SORT diff --git a/arch/microblaze/mm/consistent.c b/arch/microblaze/mm/consistent.c index cede7c5e8135..e09b66e43cb6 100644 --- a/arch/microblaze/mm/consistent.c +++ b/arch/microblaze/mm/consistent.c @@ -40,7 +40,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size) #define UNCACHED_SHADOW_MASK 0 #endif /* CONFIG_XILINX_UNCACHED_SHADOW */ -void *uncached_kernel_address(void *ptr) +void *arch_dma_set_uncached(void *ptr, size_t size) { unsigned long addr = (unsigned long)ptr; diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 797d7f1ad5fe..489185db501e 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1187,8 +1187,9 @@ config DMA_NONCOHERENT # significant advantages. # select ARCH_HAS_DMA_WRITE_COMBINE + select ARCH_HAS_DMA_PREP_COHERENT select ARCH_HAS_SYNC_DMA_FOR_DEVICE - select ARCH_HAS_UNCACHED_SEGMENT + select ARCH_HAS_DMA_SET_UNCACHED select DMA_NONCOHERENT_MMAP select DMA_NONCOHERENT_CACHE_SYNC select NEED_DMA_MAP_STATE diff --git a/arch/mips/mm/dma-noncoherent.c b/arch/mips/mm/dma-noncoherent.c index 77dce28ad0a0..fcea92d95d86 100644 --- a/arch/mips/mm/dma-noncoherent.c +++ b/arch/mips/mm/dma-noncoherent.c @@ -49,7 +49,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size) dma_cache_wback_inv((unsigned long)page_address(page), size); } -void *uncached_kernel_address(void *addr) +void *arch_dma_set_uncached(void *addr, size_t size) { return (void *)(__pa(addr) + UNCAC_BASE); } diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig index 44b5da37e8bd..2fc4ed210b5f 100644 --- a/arch/nios2/Kconfig +++ b/arch/nios2/Kconfig @@ -2,9 +2,10 @@ config NIOS2 def_bool y select ARCH_32BIT_OFF_T + select ARCH_HAS_DMA_PREP_COHERENT select ARCH_HAS_SYNC_DMA_FOR_CPU select ARCH_HAS_SYNC_DMA_FOR_DEVICE - select ARCH_HAS_UNCACHED_SEGMENT + select ARCH_HAS_DMA_SET_UNCACHED select ARCH_NO_SWAP select TIMER_OF select GENERIC_ATOMIC64 diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c index f30f2749257c..fd887d5f3f9a 100644 --- a/arch/nios2/mm/dma-mapping.c +++ b/arch/nios2/mm/dma-mapping.c @@ -67,7 +67,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size) flush_dcache_range(start, start + size); } -void *uncached_kernel_address(void *ptr) +void *arch_dma_set_uncached(void *ptr, size_t size) { unsigned long addr = (unsigned long)ptr; diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 32ee759a3fda..de229424b659 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -6,7 +6,7 @@ config XTENSA select ARCH_HAS_DMA_PREP_COHERENT if MMU select ARCH_HAS_SYNC_DMA_FOR_CPU if MMU select ARCH_HAS_SYNC_DMA_FOR_DEVICE if MMU - select ARCH_HAS_UNCACHED_SEGMENT if MMU + select ARCH_HAS_DMA_SET_UNCACHED if MMU select ARCH_USE_QUEUED_RWLOCKS select ARCH_USE_QUEUED_SPINLOCKS select ARCH_WANT_FRAME_POINTERS diff --git a/arch/xtensa/kernel/pci-dma.c b/arch/xtensa/kernel/pci-dma.c index 6a685545d5c9..17c4384f8495 100644 --- a/arch/xtensa/kernel/pci-dma.c +++ b/arch/xtensa/kernel/pci-dma.c @@ -92,7 +92,7 @@ void arch_dma_prep_coherent(struct page *page, size_t size) * coherent DMA memory operations when CONFIG_MMU is not enabled. */ #ifdef CONFIG_MMU -void *uncached_kernel_address(void *p) +void *arch_dma_set_uncached(void *p, size_t size) { return p + XCHAL_KSEG_BYPASS_VADDR - XCHAL_KSEG_CACHED_VADDR; } diff --git a/include/linux/dma-noncoherent.h b/include/linux/dma-noncoherent.h index b6b72e19b0cd..1a4039506673 100644 --- a/include/linux/dma-noncoherent.h +++ b/include/linux/dma-noncoherent.h @@ -108,6 +108,6 @@ static inline void arch_dma_prep_coherent(struct page *page, size_t size) } #endif /* CONFIG_ARCH_HAS_DMA_PREP_COHERENT */ -void *uncached_kernel_address(void *addr); +void *arch_dma_set_uncached(void *addr, size_t size); #endif /* _LINUX_DMA_NONCOHERENT_H */ diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 650580fbbff3..baf4e93735c3 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -192,10 +192,12 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, memset(ret, 0, size); - if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && dma_alloc_need_uncached(dev, attrs)) { arch_dma_prep_coherent(page, size); - ret = uncached_kernel_address(ret); + ret = arch_dma_set_uncached(ret, size); + if (IS_ERR(ret)) + goto out_free_pages; } done: if (force_dma_unencrypted(dev)) @@ -236,7 +238,7 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { - if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && dma_alloc_need_uncached(dev, attrs)) return arch_dma_alloc(dev, size, dma_handle, gfp, attrs); @@ -246,7 +248,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { - if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) && + if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && dma_alloc_need_uncached(dev, attrs)) arch_dma_free(dev, size, cpu_addr, dma_addr, attrs); -- cgit v1.2.3-58-ga151 From 999a5d1203baa7cff00586361feae263ee3f23a5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 21 Feb 2020 12:35:05 -0800 Subject: dma-direct: provide a arch_dma_clear_uncached hook This allows the arch code to reset the page tables to cached access when freeing a dma coherent allocation that was set to uncached using arch_dma_set_uncached. Signed-off-by: Christoph Hellwig Reviewed-by: Robin Murphy --- arch/Kconfig | 7 +++++++ include/linux/dma-noncoherent.h | 1 + kernel/dma/direct.c | 2 ++ 3 files changed, 10 insertions(+) (limited to 'arch/Kconfig') diff --git a/arch/Kconfig b/arch/Kconfig index 090cfe0c82a7..c26302f90c96 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -255,6 +255,13 @@ config ARCH_HAS_SET_DIRECT_MAP config ARCH_HAS_DMA_SET_UNCACHED bool +# +# Select if the architectures provides the arch_dma_clear_uncached symbol +# to undo an in-place page table remap for uncached access. +# +config ARCH_HAS_DMA_CLEAR_UNCACHED + bool + # Select if arch init_task must go in the __init_task_data section config ARCH_TASK_STRUCT_ON_STACK bool diff --git a/include/linux/dma-noncoherent.h b/include/linux/dma-noncoherent.h index 1a4039506673..b59f1b6be3e9 100644 --- a/include/linux/dma-noncoherent.h +++ b/include/linux/dma-noncoherent.h @@ -109,5 +109,6 @@ static inline void arch_dma_prep_coherent(struct page *page, size_t size) #endif /* CONFIG_ARCH_HAS_DMA_PREP_COHERENT */ void *arch_dma_set_uncached(void *addr, size_t size); +void arch_dma_clear_uncached(void *addr, size_t size); #endif /* _LINUX_DMA_NONCOHERENT_H */ diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index baf4e93735c3..412f560dc69f 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -231,6 +231,8 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, if (IS_ENABLED(CONFIG_DMA_REMAP) && is_vmalloc_addr(cpu_addr)) vunmap(cpu_addr); + else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED)) + arch_dma_clear_uncached(cpu_addr, size); dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size); } -- cgit v1.2.3-58-ga151