diff options
Diffstat (limited to 'kernel/dma/mapping.c')
| -rw-r--r-- | kernel/dma/mapping.c | 644 |
1 files changed, 644 insertions, 0 deletions
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c new file mode 100644 index 000000000..51bb8fa8e --- /dev/null +++ b/kernel/dma/mapping.c @@ -0,0 +1,644 @@ +// 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/memblock.h> /* for max_pfn */ +#include <linux/acpi.h> +#include <linux/dma-map-ops.h> +#include <linux/export.h> +#include <linux/gfp.h> +#include <linux/of_device.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include "debug.h" +#include "direct.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_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); + +static bool dma_go_direct(struct device *dev, dma_addr_t mask, + const struct dma_map_ops *ops) +{ + if (likely(!ops)) + return true; +#ifdef CONFIG_DMA_OPS_BYPASS + if (dev->dma_ops_bypass) + return min_not_zero(mask, dev->bus_dma_limit) >= + dma_direct_get_required_mask(dev); +#endif + return false; +} + + +/* + * Check if the devices uses a direct mapping for streaming DMA operations. + * This allows IOMMU drivers to set a bypass mode if the DMA mask is large + * enough. + */ +static inline bool dma_alloc_direct(struct device *dev, + const struct dma_map_ops *ops) +{ + return dma_go_direct(dev, dev->coherent_dma_mask, ops); +} + +static inline bool dma_map_direct(struct device *dev, + const struct dma_map_ops *ops) +{ + return dma_go_direct(dev, *dev->dma_mask, ops); +} + +dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, + size_t offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + dma_addr_t addr; + + BUG_ON(!valid_dma_direction(dir)); + + if (WARN_ON_ONCE(!dev->dma_mask)) + return DMA_MAPPING_ERROR; + + if (dma_map_direct(dev, ops)) + addr = dma_direct_map_page(dev, page, offset, size, dir, attrs); + else + addr = ops->map_page(dev, page, offset, size, dir, attrs); + debug_dma_map_page(dev, page, offset, size, dir, addr); + + return addr; +} +EXPORT_SYMBOL(dma_map_page_attrs); + +void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (dma_map_direct(dev, ops)) + dma_direct_unmap_page(dev, addr, size, dir, attrs); + else if (ops->unmap_page) + ops->unmap_page(dev, addr, size, dir, attrs); + debug_dma_unmap_page(dev, addr, size, dir); +} +EXPORT_SYMBOL(dma_unmap_page_attrs); + +/* + * dma_maps_sg_attrs returns 0 on error and > 0 on success. + * It should never return a value < 0. + */ +int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir, unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + int ents; + + BUG_ON(!valid_dma_direction(dir)); + + if (WARN_ON_ONCE(!dev->dma_mask)) + return 0; + + if (dma_map_direct(dev, ops)) + ents = dma_direct_map_sg(dev, sg, nents, dir, attrs); + else + ents = ops->map_sg(dev, sg, nents, dir, attrs); + BUG_ON(ents < 0); + debug_dma_map_sg(dev, sg, nents, ents, dir); + + return ents; +} +EXPORT_SYMBOL(dma_map_sg_attrs); + +void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir, + unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + debug_dma_unmap_sg(dev, sg, nents, dir); + if (dma_map_direct(dev, ops)) + dma_direct_unmap_sg(dev, sg, nents, dir, attrs); + else if (ops->unmap_sg) + ops->unmap_sg(dev, sg, nents, dir, attrs); +} +EXPORT_SYMBOL(dma_unmap_sg_attrs); + +dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + dma_addr_t addr = DMA_MAPPING_ERROR; + + BUG_ON(!valid_dma_direction(dir)); + + if (WARN_ON_ONCE(!dev->dma_mask)) + return DMA_MAPPING_ERROR; + + /* Don't allow RAM to be mapped */ + if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr)))) + return DMA_MAPPING_ERROR; + + if (dma_map_direct(dev, ops)) + addr = dma_direct_map_resource(dev, phys_addr, size, dir, attrs); + else if (ops->map_resource) + addr = ops->map_resource(dev, phys_addr, size, dir, attrs); + + debug_dma_map_resource(dev, phys_addr, size, dir, addr); + return addr; +} +EXPORT_SYMBOL(dma_map_resource); + +void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (!dma_map_direct(dev, ops) && ops->unmap_resource) + ops->unmap_resource(dev, addr, size, dir, attrs); + debug_dma_unmap_resource(dev, addr, size, dir); +} +EXPORT_SYMBOL(dma_unmap_resource); + +void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size, + enum dma_data_direction dir) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (dma_map_direct(dev, ops)) + dma_direct_sync_single_for_cpu(dev, addr, size, dir); + else if (ops->sync_single_for_cpu) + ops->sync_single_for_cpu(dev, addr, size, dir); + debug_dma_sync_single_for_cpu(dev, addr, size, dir); +} +EXPORT_SYMBOL(dma_sync_single_for_cpu); + +void dma_sync_single_for_device(struct device *dev, dma_addr_t addr, + size_t size, enum dma_data_direction dir) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (dma_map_direct(dev, ops)) + dma_direct_sync_single_for_device(dev, addr, size, dir); + else if (ops->sync_single_for_device) + ops->sync_single_for_device(dev, addr, size, dir); + debug_dma_sync_single_for_device(dev, addr, size, dir); +} +EXPORT_SYMBOL(dma_sync_single_for_device); + +void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, + int nelems, enum dma_data_direction dir) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (dma_map_direct(dev, ops)) + dma_direct_sync_sg_for_cpu(dev, sg, nelems, dir); + else if (ops->sync_sg_for_cpu) + ops->sync_sg_for_cpu(dev, sg, nelems, dir); + debug_dma_sync_sg_for_cpu(dev, sg, nelems, dir); +} +EXPORT_SYMBOL(dma_sync_sg_for_cpu); + +void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, + int nelems, enum dma_data_direction dir) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (dma_map_direct(dev, ops)) + dma_direct_sync_sg_for_device(dev, sg, nelems, dir); + else if (ops->sync_sg_for_device) + ops->sync_sg_for_device(dev, sg, nelems, dir); + debug_dma_sync_sg_for_device(dev, sg, nelems, dir); +} +EXPORT_SYMBOL(dma_sync_sg_for_device); + +/* + * The whole dma_get_sgtable() idea is fundamentally unsafe - it seems + * that the intention is to allow exporting memory allocated via the + * coherent DMA APIs through the dma_buf API, which only accepts a + * scattertable. This presents a couple of problems: + * 1. Not all memory allocated via the coherent DMA APIs is backed by + * a struct page + * 2. Passing coherent DMA memory into the streaming APIs is not allowed + * as we will try to flush the memory through a different alias to that + * actually being used (and the flushes are redundant.) + */ +int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_alloc_direct(dev, ops)) + return dma_direct_get_sgtable(dev, sgt, cpu_addr, dma_addr, + size, attrs); + if (!ops->get_sgtable) + return -ENXIO; + return ops->get_sgtable(dev, sgt, cpu_addr, dma_addr, size, attrs); +} +EXPORT_SYMBOL(dma_get_sgtable_attrs); + +#ifdef CONFIG_MMU +/* + * Return the page attributes used for mapping dma_alloc_* memory, either in + * kernel space if remapping is needed, or to userspace through dma_mmap_*. + */ +pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs) +{ + if (force_dma_unencrypted(dev)) + prot = pgprot_decrypted(prot); + if (dev_is_dma_coherent(dev)) + return prot; +#ifdef CONFIG_ARCH_HAS_DMA_WRITE_COMBINE + if (attrs & DMA_ATTR_WRITE_COMBINE) + return pgprot_writecombine(prot); +#endif + return pgprot_dmacoherent(prot); +} +#endif /* CONFIG_MMU */ + +/** + * dma_can_mmap - check if a given device supports dma_mmap_* + * @dev: device to check + * + * Returns %true if @dev supports dma_mmap_coherent() and dma_mmap_attrs() to + * map DMA allocations to userspace. + */ +bool dma_can_mmap(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_alloc_direct(dev, ops)) + return dma_direct_can_mmap(dev); + return ops->mmap != NULL; +} +EXPORT_SYMBOL_GPL(dma_can_mmap); + +/** + * dma_mmap_attrs - map a coherent DMA allocation into user space + * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices + * @vma: vm_area_struct describing requested user mapping + * @cpu_addr: kernel CPU-view address returned from dma_alloc_attrs + * @dma_addr: device-view address returned from dma_alloc_attrs + * @size: size of memory originally requested in dma_alloc_attrs + * @attrs: attributes of mapping properties requested in dma_alloc_attrs + * + * Map a coherent DMA buffer previously allocated by dma_alloc_attrs into user + * space. The coherent DMA buffer must not be freed by the driver until the + * user space mapping has been released. + */ +int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_alloc_direct(dev, ops)) + return dma_direct_mmap(dev, vma, cpu_addr, dma_addr, size, + attrs); + if (!ops->mmap) + return -ENXIO; + return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs); +} +EXPORT_SYMBOL(dma_mmap_attrs); + +u64 dma_get_required_mask(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_alloc_direct(dev, ops)) + return dma_direct_get_required_mask(dev); + if (ops->get_required_mask) + return ops->get_required_mask(dev); + + /* + * We require every DMA ops implementation to at least support a 32-bit + * DMA mask (and use bounce buffering if that isn't supported in + * hardware). As the direct mapping code has its own routine to + * actually report an optimal mask we default to 32-bit here as that + * is the right thing for most IOMMUs, and at least not actively + * harmful in general. + */ + return DMA_BIT_MASK(32); +} +EXPORT_SYMBOL_GPL(dma_get_required_mask); + +void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, + gfp_t flag, unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + void *cpu_addr; + + WARN_ON_ONCE(!dev->coherent_dma_mask); + + if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr)) + return cpu_addr; + + /* let the implementation decide on the zone to allocate from: */ + flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM); + + if (dma_alloc_direct(dev, ops)) + cpu_addr = dma_direct_alloc(dev, size, dma_handle, flag, attrs); + else if (ops->alloc) + cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs); + else + return NULL; + + debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr); + return cpu_addr; +} +EXPORT_SYMBOL(dma_alloc_attrs); + +void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr, + dma_addr_t dma_handle, unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_release_from_dev_coherent(dev, get_order(size), cpu_addr)) + return; + /* + * On non-coherent platforms which implement DMA-coherent buffers via + * non-cacheable remaps, ops->free() may call vunmap(). Thus getting + * this far in IRQ context is a) at risk of a BUG_ON() or trying to + * sleep on some machines, and b) an indication that the driver is + * probably misusing the coherent API anyway. + */ + WARN_ON(irqs_disabled()); + + if (!cpu_addr) + return; + + debug_dma_free_coherent(dev, size, cpu_addr, dma_handle); + if (dma_alloc_direct(dev, ops)) + dma_direct_free(dev, size, cpu_addr, dma_handle, attrs); + else if (ops->free) + ops->free(dev, size, cpu_addr, dma_handle, attrs); +} +EXPORT_SYMBOL(dma_free_attrs); + +struct page *dma_alloc_pages(struct device *dev, size_t size, + dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + struct page *page; + + if (WARN_ON_ONCE(!dev->coherent_dma_mask)) + return NULL; + if (WARN_ON_ONCE(gfp & (__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM))) + return NULL; + + size = PAGE_ALIGN(size); + if (dma_alloc_direct(dev, ops)) + page = dma_direct_alloc_pages(dev, size, dma_handle, dir, gfp); + else if (ops->alloc_pages) + page = ops->alloc_pages(dev, size, dma_handle, dir, gfp); + else + return NULL; + + debug_dma_map_page(dev, page, 0, size, dir, *dma_handle); + + return page; +} +EXPORT_SYMBOL_GPL(dma_alloc_pages); + +void dma_free_pages(struct device *dev, size_t size, struct page *page, + dma_addr_t dma_handle, enum dma_data_direction dir) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + size = PAGE_ALIGN(size); + debug_dma_unmap_page(dev, dma_handle, size, dir); + + if (dma_alloc_direct(dev, ops)) + dma_direct_free_pages(dev, size, page, dma_handle, dir); + else if (ops->free_pages) + ops->free_pages(dev, size, page, dma_handle, dir); +} +EXPORT_SYMBOL_GPL(dma_free_pages); + +void *dma_alloc_noncoherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + void *vaddr; + + if (!ops || !ops->alloc_noncoherent) { + struct page *page; + + page = dma_alloc_pages(dev, size, dma_handle, dir, gfp); + if (!page) + return NULL; + return page_address(page); + } + + size = PAGE_ALIGN(size); + vaddr = ops->alloc_noncoherent(dev, size, dma_handle, dir, gfp); + if (vaddr) + debug_dma_map_page(dev, virt_to_page(vaddr), 0, size, dir, + *dma_handle); + return vaddr; +} +EXPORT_SYMBOL_GPL(dma_alloc_noncoherent); + +void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr, + dma_addr_t dma_handle, enum dma_data_direction dir) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (!ops || !ops->free_noncoherent) { + dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir); + return; + } + + size = PAGE_ALIGN(size); + debug_dma_unmap_page(dev, dma_handle, size, dir); + ops->free_noncoherent(dev, size, vaddr, dma_handle, dir); +} +EXPORT_SYMBOL_GPL(dma_free_noncoherent); + +int dma_supported(struct device *dev, u64 mask) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + /* + * ->dma_supported sets the bypass flag, so we must always call + * into the method here unless the device is truly direct mapped. + */ + if (!ops) + return dma_direct_supported(dev, mask); + if (!ops->dma_supported) + return 1; + return ops->dma_supported(dev, mask); +} +EXPORT_SYMBOL(dma_supported); + +#ifdef CONFIG_ARCH_HAS_DMA_SET_MASK +void arch_dma_set_mask(struct device *dev, u64 mask); +#else +#define arch_dma_set_mask(dev, mask) do { } while (0) +#endif + +int dma_set_mask(struct device *dev, u64 mask) +{ + /* + * Truncate the mask to the actually supported dma_addr_t width to + * avoid generating unsupportable addresses. + */ + mask = (dma_addr_t)mask; + + if (!dev->dma_mask || !dma_supported(dev, mask)) + return -EIO; + + arch_dma_set_mask(dev, mask); + *dev->dma_mask = mask; + return 0; +} +EXPORT_SYMBOL(dma_set_mask); + +#ifndef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK +int dma_set_coherent_mask(struct device *dev, u64 mask) +{ + /* + * Truncate the mask to the actually supported dma_addr_t width to + * avoid generating unsupportable addresses. + */ + mask = (dma_addr_t)mask; + + if (!dma_supported(dev, mask)) + return -EIO; + + dev->coherent_dma_mask = mask; + return 0; +} +EXPORT_SYMBOL(dma_set_coherent_mask); +#endif + +size_t dma_max_mapping_size(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + size_t size = SIZE_MAX; + + if (dma_map_direct(dev, ops)) + size = dma_direct_max_mapping_size(dev); + else if (ops && ops->max_mapping_size) + size = ops->max_mapping_size(dev); + + return size; +} +EXPORT_SYMBOL_GPL(dma_max_mapping_size); + +bool dma_need_sync(struct device *dev, dma_addr_t dma_addr) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_map_direct(dev, ops)) + return dma_direct_need_sync(dev, dma_addr); + return ops->sync_single_for_cpu || ops->sync_single_for_device; +} +EXPORT_SYMBOL_GPL(dma_need_sync); + +unsigned long dma_get_merge_boundary(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (!ops || !ops->get_merge_boundary) + return 0; /* can't merge */ + + return ops->get_merge_boundary(dev); +} +EXPORT_SYMBOL_GPL(dma_get_merge_boundary); |