/* SPDX-License-Identifier: GPL-2.0 */ /* * This header is for implementations of dma_map_ops and related code. * It should not be included in drivers just using the DMA API. */ #ifndef _LINUX_DMA_MAP_OPS_H #define _LINUX_DMA_MAP_OPS_H #include #include #include struct cma; struct iommu_ops; /* * Values for struct dma_map_ops.flags: * * DMA_F_PCI_P2PDMA_SUPPORTED: Indicates the dma_map_ops implementation can * handle PCI P2PDMA pages in the map_sg/unmap_sg operation. */ #define DMA_F_PCI_P2PDMA_SUPPORTED (1 << 0) struct dma_map_ops { unsigned int flags; void *(*alloc)(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); void (*free)(struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle, unsigned long attrs); struct page *(*alloc_pages)(struct device *dev, size_t size, dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); void (*free_pages)(struct device *dev, size_t size, struct page *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir); struct sg_table *(*alloc_noncontiguous)(struct device *dev, size_t size, enum dma_data_direction dir, gfp_t gfp, unsigned long attrs); void (*free_noncontiguous)(struct device *dev, size_t size, struct sg_table *sgt, enum dma_data_direction dir); int (*mmap)(struct device *, struct vm_area_struct *, void *, dma_addr_t, size_t, unsigned long attrs); int (*get_sgtable)(struct device *dev, struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr, size_t size, unsigned long attrs); dma_addr_t (*map_page)(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, unsigned long attrs); void (*unmap_page)(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir, unsigned long attrs); /* * map_sg should return a negative error code on error. See * dma_map_sgtable() for a list of appropriate error codes * and their meanings. */ int (*map_sg)(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir, unsigned long attrs); void (*unmap_sg)(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir, unsigned long attrs); dma_addr_t (*map_resource)(struct device *dev, phys_addr_t phys_addr, size_t size, enum dma_data_direction dir, unsigned long attrs); void (*unmap_resource)(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir, unsigned long attrs); void (*sync_single_for_cpu)(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir); void (*sync_single_for_device)(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir); void (*sync_sg_for_cpu)(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir); void (*sync_sg_for_device)(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir); void (*cache_sync)(struct device *dev, void *vaddr, size_t size, enum dma_data_direction direction); int (*dma_supported)(struct device *dev, u64 mask); u64 (*get_required_mask)(struct device *dev); size_t (*max_mapping_size)(struct device *dev); size_t (*opt_mapping_size)(void); unsigned long (*get_merge_boundary)(struct device *dev); }; #ifdef CONFIG_DMA_OPS #include static inline const struct dma_map_ops *get_dma_ops(struct device *dev) { if (dev->dma_ops) return dev->dma_ops; return get_arch_dma_ops(); } static inline void set_dma_ops(struct device *dev, const struct dma_map_ops *dma_ops) { dev->dma_ops = dma_ops; } #else /* CONFIG_DMA_OPS */ static inline const struct dma_map_ops *get_dma_ops(struct device *dev) { return NULL; } static inline void set_dma_ops(struct device *dev, const struct dma_map_ops *dma_ops) { } #endif /* CONFIG_DMA_OPS */ #ifdef CONFIG_DMA_CMA extern struct cma *dma_contiguous_default_area; static inline struct cma *dev_get_cma_area(struct device *dev) { if (dev && dev->cma_area) return dev->cma_area; return dma_contiguous_default_area; } void dma_contiguous_reserve(phys_addr_t addr_limit); int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma, bool fixed); struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, unsigned int order, bool no_warn); bool dma_release_from_contiguous(struct device *dev, struct page *pages, int count); struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp); void dma_free_contiguous(struct device *dev, struct page *page, size_t size); void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size); #else /* CONFIG_DMA_CMA */ static inline struct cma *dev_get_cma_area(struct device *dev) { return NULL; } static inline void dma_contiguous_reserve(phys_addr_t limit) { } static inline int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma, bool fixed) { return -ENOSYS; } static inline struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, unsigned int order, bool no_warn) { return NULL; } static inline bool dma_release_from_contiguous(struct device *dev, struct page *pages, int count) { return false; } /* Use fallback alloc() and free() when CONFIG_DMA_CMA=n */ static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) { return NULL; } static inline void dma_free_contiguous(struct device *dev, struct page *page, size_t size) { __free_pages(page, get_order(size)); } #endif /* CONFIG_DMA_CMA*/ #ifdef CONFIG_DMA_DECLARE_COHERENT int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size); void dma_release_coherent_memory(struct device *dev); int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size, dma_addr_t *dma_handle, void **ret); int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr); int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, size_t size, int *ret); #else static inline int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size) { return -ENOSYS; } #define dma_alloc_from_dev_coherent(dev, size, handle, ret) (0) #define dma_release_from_dev_coherent(dev, order, vaddr) (0) #define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0) static inline void dma_release_coherent_memory(struct device *dev) { } #endif /* CONFIG_DMA_DECLARE_COHERENT */ #ifdef CONFIG_DMA_GLOBAL_POOL void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size, dma_addr_t *dma_handle); int dma_release_from_global_coherent(int order, void *vaddr); int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr, size_t size, int *ret); int dma_init_global_coherent(phys_addr_t phys_addr, size_t size); #else static inline void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size, dma_addr_t *dma_handle) { return NULL; } static inline int dma_release_from_global_coherent(int order, void *vaddr) { return 0; } static inline int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *cpu_addr, size_t size, int *ret) { return 0; } #endif /* CONFIG_DMA_GLOBAL_POOL */ /* * This is the actual return value from the ->alloc_noncontiguous method. * The users of the DMA API should only care about the sg_table, but to make * the DMA-API internal vmaping and freeing easier we stash away the page * array as well (except for the fallback case). This can go away any time, * e.g. when a vmap-variant that takes a scatterlist comes along. */ struct dma_sgt_handle { struct sg_table sgt; struct page **pages; }; #define sgt_handle(sgt) \ container_of((sgt), struct dma_sgt_handle, sgt) 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); int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start, dma_addr_t dma_start, u64 size); #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) extern bool dma_default_coherent; static inline bool dev_is_dma_coherent(struct device *dev) { return dev->dma_coherent; } #else #define dma_default_coherent true static inline bool dev_is_dma_coherent(struct device *dev) { return true; } #endif /* CONFIG_ARCH_HAS_DMA_COHERENCE_H */ /* * Check whether potential kmalloc() buffers are safe for non-coherent DMA. */ static inline bool dma_kmalloc_safe(struct device *dev, enum dma_data_direction dir) { /* * If DMA bouncing of kmalloc() buffers is disabled, the kmalloc() * caches have already been aligned to a DMA-safe size. */ if (!IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC)) return true; /* * kmalloc() buffers are DMA-safe irrespective of size if the device * is coherent or the direction is DMA_TO_DEVICE (non-desctructive * cache maintenance and benign cache line evictions). */ if (dev_is_dma_coherent(dev) || dir == DMA_TO_DEVICE) return true; return false; } /* * Check whether the given size, assuming it is for a kmalloc()'ed buffer, is * sufficiently aligned for non-coherent DMA. */ static inline bool dma_kmalloc_size_aligned(size_t size) { /* * Larger kmalloc() sizes are guaranteed to be aligned to * ARCH_DMA_MINALIGN. */ if (size >= 2 * ARCH_DMA_MINALIGN || IS_ALIGNED(kmalloc_size_roundup(size), dma_get_cache_alignment())) return true; return false; } /* * Check whether the given object size may have originated from a kmalloc() * buffer with a slab alignment below the DMA-safe alignment and needs * bouncing for non-coherent DMA. The pointer alignment is not considered and * in-structure DMA-safe offsets are the responsibility of the caller. Such * code should use the static ARCH_DMA_MINALIGN for compiler annotations. * * The heuristics can have false positives, bouncing unnecessarily, though the * buffers would be small. False negatives are theoretically possible if, for * example, multiple small kmalloc() buffers are coalesced into a larger * buffer that passes the alignment check. There are no such known constructs * in the kernel. */ static inline bool dma_kmalloc_needs_bounce(struct device *dev, size_t size, enum dma_data_direction dir) { return !dma_kmalloc_safe(dev, dir) && !dma_kmalloc_size_aligned(size); } void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); void arch_dma_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs); #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 #ifdef CONFIG_MMU /* * Page protection so that devices that can't snoop CPU caches can use the * memory coherently. We default to pgprot_noncached which is usually used * for ioremap as a safe bet, but architectures can override this with less * strict semantics if possible. */ #ifndef pgprot_dmacoherent #define pgprot_dmacoherent(prot) pgprot_noncached(prot) #endif pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs); #else static inline pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs) { return prot; /* no protection bits supported without page tables */ } #endif /* CONFIG_MMU */ #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, enum dma_data_direction dir); #else static inline void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, enum dma_data_direction dir) { } #endif /* ARCH_HAS_SYNC_DMA_FOR_DEVICE */ #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, enum dma_data_direction dir); #else static inline void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, enum dma_data_direction dir) { } #endif /* ARCH_HAS_SYNC_DMA_FOR_CPU */ #ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL void arch_sync_dma_for_cpu_all(void); #else static inline void arch_sync_dma_for_cpu_all(void) { } #endif /* CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL */ #ifdef CONFIG_ARCH_HAS_DMA_PREP_COHERENT void arch_dma_prep_coherent(struct page *page, size_t size); #else static inline void arch_dma_prep_coherent(struct page *page, size_t size) { } #endif /* CONFIG_ARCH_HAS_DMA_PREP_COHERENT */ #ifdef CONFIG_ARCH_HAS_DMA_MARK_CLEAN void arch_dma_mark_clean(phys_addr_t paddr, size_t size); #else static inline void arch_dma_mark_clean(phys_addr_t paddr, size_t size) { } #endif /* ARCH_HAS_DMA_MARK_CLEAN */ void *arch_dma_set_uncached(void *addr, size_t size); void arch_dma_clear_uncached(void *addr, size_t size); #ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr); bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle); bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg, int nents); bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg, int nents); #else #define arch_dma_map_page_direct(d, a) (false) #define arch_dma_unmap_page_direct(d, a) (false) #define arch_dma_map_sg_direct(d, s, n) (false) #define arch_dma_unmap_sg_direct(d, s, n) (false) #endif #ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, bool coherent); #else static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, bool coherent) { } #endif /* CONFIG_ARCH_HAS_SETUP_DMA_OPS */ #ifdef CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS void arch_teardown_dma_ops(struct device *dev); #else static inline void arch_teardown_dma_ops(struct device *dev) { } #endif /* CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS */ #ifdef CONFIG_DMA_API_DEBUG void dma_debug_add_bus(const struct bus_type *bus); void debug_dma_dump_mappings(struct device *dev); #else static inline void dma_debug_add_bus(const struct bus_type *bus) { } static inline void debug_dma_dump_mappings(struct device *dev) { } #endif /* CONFIG_DMA_API_DEBUG */ extern const struct dma_map_ops dma_dummy_ops; enum pci_p2pdma_map_type { /* * PCI_P2PDMA_MAP_UNKNOWN: Used internally for indicating the mapping * type hasn't been calculated yet. Functions that return this enum * never return this value. */ PCI_P2PDMA_MAP_UNKNOWN = 0, /* * PCI_P2PDMA_MAP_NOT_SUPPORTED: Indicates the transaction will * traverse the host bridge and the host bridge is not in the * allowlist. DMA Mapping routines should return an error when * this is returned. */ PCI_P2PDMA_MAP_NOT_SUPPORTED, /* * PCI_P2PDMA_BUS_ADDR: Indicates that two devices can talk to * each other directly through a PCI switch and the transaction will * not traverse the host bridge. Such a mapping should program * the DMA engine with PCI bus addresses. */ PCI_P2PDMA_MAP_BUS_ADDR, /* * PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: Indicates two devices can talk * to each other, but the transaction traverses a host bridge on the * allowlist. In this case, a normal mapping either with CPU physical * addresses (in the case of dma-direct) or IOVA addresses (in the * case of IOMMUs) should be used to program the DMA engine. */ PCI_P2PDMA_MAP_THRU_HOST_BRIDGE, }; struct pci_p2pdma_map_state { struct dev_pagemap *pgmap; int map; u64 bus_off; }; #ifdef CONFIG_PCI_P2PDMA enum pci_p2pdma_map_type pci_p2pdma_map_segment(struct pci_p2pdma_map_state *state, struct device *dev, struct scatterlist *sg); #else /* CONFIG_PCI_P2PDMA */ static inline enum pci_p2pdma_map_type pci_p2pdma_map_segment(struct pci_p2pdma_map_state *state, struct device *dev, struct scatterlist *sg) { return PCI_P2PDMA_MAP_NOT_SUPPORTED; } #endif /* CONFIG_PCI_P2PDMA */ #endif /* _LINUX_DMA_MAP_OPS_H */