Merge "arm: dma-mapping: Add dma_remap functions" (9df4af06) · Commits · e / devices / android_kernel_fairphone_FP4

arch/arm/mm/dma-mapping.c

+72 −13

Original line number	Diff line number	Diff line
		@@ -112,6 +112,21 @@ static void __dma_page_cpu_to_dev(struct page *, unsigned long,
		static void __dma_page_dev_to_cpu(struct page *, unsigned long,
		size_t, enum dma_data_direction);

		static void *
		__dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot,
		const void *caller);

		static void __dma_free_remap(void *cpu_addr, size_t size, bool no_warn);

		static inline pgprot_t __get_dma_pgprot(unsigned long attrs, pgprot_t prot);

		static void arm_dma_remap(struct device dev, void *cpu_addr,
		dma_addr_t handle, size_t size,
		unsigned long attrs);

		static void arm_dma_unremap(struct device dev, void remapped_addr,
		size_t size);

		/**
		* arm_dma_map_page - map a portion of a page for streaming DMA
		* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
		@@ -200,6 +215,8 @@ const struct dma_map_ops arm_dma_ops = {
		.sync_sg_for_device = arm_dma_sync_sg_for_device,
		.mapping_error = arm_dma_mapping_error,
		.dma_supported = arm_dma_supported,
		.remap = arm_dma_remap,
		.unremap = arm_dma_unremap,
		};
		EXPORT_SYMBOL(arm_dma_ops);

		@@ -526,12 +543,28 @@ static int __dma_update_pte(pte_t *pte, pgtable_t token, unsigned long addr,
		return 0;
		}

		static void __dma_remap(struct page *page, size_t size, pgprot_t prot)
		static int __dma_clear_pte(pte_t *pte, pgtable_t token, unsigned long addr,
		void *data)
		{
		pte_clear(&init_mm, addr, pte);
		return 0;
		}

		static void __dma_remap(struct page *page, size_t size, pgprot_t prot,
		bool want_vaddr)
		{
		unsigned long start = (unsigned long) page_address(page);
		unsigned end = start + size;
		int (func)(pte_t pte, pgtable_t token, unsigned long addr,
		void *data);

		if (!want_vaddr)
		func = __dma_clear_pte;
		else
		func = __dma_update_pte;

		apply_to_page_range(&init_mm, start, size, __dma_update_pte, &prot);
		apply_to_page_range(&init_mm, start, size, func, &prot);
		mb(); /Ensure pte's are updated /
		flush_tlb_kernel_range(start, end);
		}

		@@ -614,9 +647,6 @@ static void __alloc_from_contiguous(struct device dev, size_t size,

		__dma_clear_buffer(page, size, coherent_flag);

		if (!want_vaddr)
		goto out;

		if (PageHighMem(page)) {
		ptr = __dma_alloc_remap(page, size, GFP_KERNEL, prot, caller);
		if (!ptr) {
		@@ -624,11 +654,10 @@ static void __alloc_from_contiguous(struct device dev, size_t size,
		return NULL;
		}
		} else {
		__dma_remap(page, size, prot);
		__dma_remap(page, size, prot, want_vaddr);
		ptr = page_address(page);
		}

		out:
		*ret_page = page;
		return ptr;
		}
		@@ -636,12 +665,10 @@ static void __alloc_from_contiguous(struct device dev, size_t size,
		static void __free_from_contiguous(struct device dev, struct page page,
		void *cpu_addr, size_t size, bool want_vaddr)
		{
		if (want_vaddr) {
		if (PageHighMem(page))
		__dma_free_remap(cpu_addr, size, true);
		else
		__dma_remap(page, size, PAGE_KERNEL);
		}
		__dma_remap(page, size, PAGE_KERNEL, true);
		dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT);
		}

		@@ -868,6 +895,38 @@ static int __arm_dma_mmap(struct device dev, struct vm_area_struct vma,
		return ret;
		}

		static void arm_dma_remap(struct device dev, void *cpu_addr,
		dma_addr_t handle, size_t size,
		unsigned long attrs)
		{
		void *ptr;
		struct page *page = pfn_to_page(dma_to_pfn(dev, handle));
		pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL);
		unsigned long offset = handle & ~PAGE_MASK;

		size = PAGE_ALIGN(size + offset);
		ptr = __dma_alloc_remap(page, size, GFP_KERNEL, prot,
		__builtin_return_address(0));
		return ptr ? ptr + offset : ptr;
		}

		static void arm_dma_unremap(struct device dev, void remapped_addr,
		size_t size)
		{
		unsigned int flags = VM_ARM_DMA_CONSISTENT \| VM_USERMAP;
		struct vm_struct *area;

		remapped_addr = (void *)((unsigned long)remapped_addr & PAGE_MASK);

		area = find_vm_area(remapped_addr);
		if (!area \|\| (area->flags & flags) != flags) {
		WARN(1, "trying to free invalid coherent area: %pK\n",
		remapped_addr);
		return;
		}

		vunmap(remapped_addr);
		}
		/*
		* Create userspace mapping for the DMA-coherent memory.
		*/