// SPDX-License-Identifier: GPL-2.0/* * arch-independent dma-mapping routines * * Copyright (c) 2006  SUSE Linux Products GmbH * Copyright (c) 2006  Tejun Heo <teheo@suse.de> */ #include <linux/acpi.h>#include <linux/dma-noncoherent.h>#include <linux/export.h>#include <linux/gfp.h>#include <linux/of_device.h>#include <linux/slab.h>#include <linux/vmalloc.h> /* * Managed DMA API */struct dma_devres {	size_t		size;	void		*vaddr;	dma_addr_t	dma_handle;	unsigned long	attrs;}; static void dmam_release(struct device *dev, void *res){	struct dma_devres *this = res; 	dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,			this->attrs);} static int dmam_match(struct device *dev, void *res, void *match_data){	struct dma_devres *this = res, *match = match_data; 	if (this->vaddr == match->vaddr) {		WARN_ON(this->size != match->size ||			this->dma_handle != match->dma_handle);		return 1;	}	return 0;} /** * dmam_alloc_coherent - Managed dma_alloc_coherent() * @dev: Device to allocate coherent memory for * @size: Size of allocation * @dma_handle: Out argument for allocated DMA handle * @gfp: Allocation flags * * Managed dma_alloc_coherent().  Memory allocated using this function * will be automatically released on driver detach. * * RETURNS: * Pointer to allocated memory on success, NULL on failure. */void *dmam_alloc_coherent(struct device *dev, size_t size,			   dma_addr_t *dma_handle, gfp_t gfp){	struct dma_devres *dr;	void *vaddr; 	dr = devres_alloc(dmam_release, sizeof(*dr), gfp);	if (!dr)		return NULL; 	vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);	if (!vaddr) {		devres_free(dr);		return NULL;	} 	dr->vaddr = vaddr;	dr->dma_handle = *dma_handle;	dr->size = size; 	devres_add(dev, dr); 	return vaddr;}EXPORT_SYMBOL(dmam_alloc_coherent); /** * dmam_free_coherent - Managed dma_free_coherent() * @dev: Device to free coherent memory for * @size: Size of allocation * @vaddr: Virtual address of the memory to free * @dma_handle: DMA handle of the memory to free * * Managed dma_free_coherent(). */void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,			dma_addr_t dma_handle){	struct dma_devres match_data = { size, vaddr, dma_handle }; 	dma_free_coherent(dev, size, vaddr, dma_handle);	WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));}EXPORT_SYMBOL(dmam_free_coherent); /** * dmam_alloc_attrs - Managed dma_alloc_attrs() * @dev: Device to allocate non_coherent memory for * @size: Size of allocation * @dma_handle: Out argument for allocated DMA handle * @gfp: Allocation flags * @attrs: Flags in the DMA_ATTR_* namespace. * * Managed dma_alloc_attrs().  Memory allocated using this function will be * automatically released on driver detach. * * RETURNS: * Pointer to allocated memory on success, NULL on failure. */void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,		gfp_t gfp, unsigned long attrs){	struct dma_devres *dr;	void *vaddr; 	dr = devres_alloc(dmam_release, sizeof(*dr), gfp);	if (!dr)		return NULL; 	vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);	if (!vaddr) {		devres_free(dr);		return NULL;	} 	dr->vaddr = vaddr;	dr->dma_handle = *dma_handle;	dr->size = size;	dr->attrs = attrs; 	devres_add(dev, dr); 	return vaddr;}EXPORT_SYMBOL(dmam_alloc_attrs); #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT static void dmam_coherent_decl_release(struct device *dev, void *res){	dma_release_declared_memory(dev);} /** * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory() * @dev: Device to declare coherent memory for * @phys_addr: Physical address of coherent memory to be declared * @device_addr: Device address of coherent memory to be declared * @size: Size of coherent memory to be declared * @flags: Flags * * Managed dma_declare_coherent_memory(). * * RETURNS: * 0 on success, -errno on failure. */int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,				 dma_addr_t device_addr, size_t size, int flags){	void *res;	int rc; 	res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);	if (!res)		return -ENOMEM; 	rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,					 flags);	if (!rc)		devres_add(dev, res);	else		devres_free(res); 	return rc;}EXPORT_SYMBOL(dmam_declare_coherent_memory); /** * dmam_release_declared_memory - Managed dma_release_declared_memory(). * @dev: Device to release declared coherent memory for * * Managed dmam_release_declared_memory(). */void dmam_release_declared_memory(struct device *dev){	WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));}EXPORT_SYMBOL(dmam_release_declared_memory); #endif /* * Create scatter-list for the already allocated DMA buffer. */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){	struct page *page;	int ret; 	if (!dev_is_dma_coherent(dev)) {		if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))			return -ENXIO; 		page = pfn_to_page(arch_dma_coherent_to_pfn(dev, cpu_addr,				dma_addr));	} else {		page = virt_to_page(cpu_addr);	} 	ret = sg_alloc_table(sgt, 1, GFP_KERNEL);	if (!ret)		sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);	return ret;}EXPORT_SYMBOL(dma_common_get_sgtable); /* * Create userspace mapping for the DMA-coherent memory. */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){#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP	unsigned long user_count = vma_pages(vma);	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;	unsigned long off = vma->vm_pgoff;	unsigned long pfn;	int ret = -ENXIO; 	vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs); 	if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))		return ret; 	if (off >= count || user_count > count - off)		return -ENXIO; 	if (!dev_is_dma_coherent(dev)) {		if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))			return -ENXIO;		pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr);	} else {		pfn = page_to_pfn(virt_to_page(cpu_addr));	} 	return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,			user_count << PAGE_SHIFT, vma->vm_page_prot);#else	return -ENXIO;#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */}EXPORT_SYMBOL(dma_common_mmap); #ifdef CONFIG_MMUstatic 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