include/linux/swiotlb.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __LINUX_SWIOTLB_H
   3 #define __LINUX_SWIOTLB_H
   4
   5 #include <linux/device.h>
   6 #include <linux/dma-direction.h>
   7 #include <linux/init.h>
   8 #include <linux/types.h>
   9 #include <linux/limits.h>
  10 #include <linux/spinlock.h>
  11
  12 struct device;
  13 struct page;
  14 struct scatterlist;
  15
  16 enum swiotlb_force {
  17         SWIOTLB_NORMAL,         /* Default - depending on HW DMA mask etc. */
  18         SWIOTLB_FORCE,          /* swiotlb=force */
  19         SWIOTLB_NO_FORCE,       /* swiotlb=noforce */
  20 };
  21
  22 /*
  23  * Maximum allowable number of contiguous slabs to map,
  24  * must be a power of 2.  What is the appropriate value ?
  25  * The complexity of {map,unmap}_single is linearly dependent on this value.
  26  */
  27 #define IO_TLB_SEGSIZE  128
  28
  29 /*
  30  * log of the size of each IO TLB slab.  The number of slabs is command line
  31  * controllable.
  32  */
  33 #define IO_TLB_SHIFT 11
  34 #define IO_TLB_SIZE (1 << IO_TLB_SHIFT)
  35
  36 /* default to 64MB */
  37 #define IO_TLB_DEFAULT_SIZE (64UL<<20)
  38
  39 extern void swiotlb_init(int verbose);
  40 int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose);
  41 unsigned long swiotlb_size_or_default(void);
  42 extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
  43 extern int swiotlb_late_init_with_default_size(size_t default_size);
  44 extern void __init swiotlb_update_mem_attributes(void);
  45
  46 phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t phys,
  47                 size_t mapping_size, size_t alloc_size,
  48                 enum dma_data_direction dir, unsigned long attrs);
  49
  50 extern void swiotlb_tbl_unmap_single(struct device *hwdev,
  51                                      phys_addr_t tlb_addr,
  52                                      size_t mapping_size,
  53                                      enum dma_data_direction dir,
  54                                      unsigned long attrs);
  55
  56 void swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
  57                 size_t size, enum dma_data_direction dir);
  58 void swiotlb_sync_single_for_cpu(struct device *dev, phys_addr_t tlb_addr,
  59                 size_t size, enum dma_data_direction dir);
  60 dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys,
  61                 size_t size, enum dma_data_direction dir, unsigned long attrs);
  62
  63 #ifdef CONFIG_SWIOTLB
  64 extern enum swiotlb_force swiotlb_force;
  65
  66 /**
  67  * struct io_tlb_mem - IO TLB Memory Pool Descriptor
  68  *
  69  * @start:      The start address of the swiotlb memory pool. Used to do a quick
  70  *              range check to see if the memory was in fact allocated by this
  71  *              API.
  72  * @end:        The end address of the swiotlb memory pool. Used to do a quick
  73  *              range check to see if the memory was in fact allocated by this
  74  *              API.
  75  * @nslabs:     The number of IO TLB blocks (in groups of 64) between @start and
  76  *              @end. For default swiotlb, this is command line adjustable via
  77  *              setup_io_tlb_npages.
  78  * @used:       The number of used IO TLB block.
  79  * @list:       The free list describing the number of free entries available
  80  *              from each index.
  81  * @index:      The index to start searching in the next round.
  82  * @orig_addr:  The original address corresponding to a mapped entry.
  83  * @alloc_size: Size of the allocated buffer.
  84  * @lock:       The lock to protect the above data structures in the map and
  85  *              unmap calls.
  86  * @debugfs:    The dentry to debugfs.
  87  * @late_alloc: %true if allocated using the page allocator
  88  * @force_bounce: %true if swiotlb bouncing is forced
  89  * @for_alloc:  %true if the pool is used for memory allocation
  90  */
  91 struct io_tlb_mem {
  92         phys_addr_t start;
  93         phys_addr_t end;
  94         unsigned long nslabs;
  95         unsigned long used;
  96         unsigned int index;
  97         spinlock_t lock;
  98         struct dentry *debugfs;
  99         bool late_alloc;
 100         bool force_bounce;
 101         bool for_alloc;
 102         struct io_tlb_slot {
 103                 phys_addr_t orig_addr;
 104                 size_t alloc_size;
 105                 unsigned int list;
 106         } *slots;
 107 };
 108 extern struct io_tlb_mem io_tlb_default_mem;
 109
 110 static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 111 {
 112         struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
 113
 114         return mem && paddr >= mem->start && paddr < mem->end;
 115 }
 116
 117 static inline bool is_swiotlb_force_bounce(struct device *dev)
 118 {
 119         struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
 120
 121         return mem && mem->force_bounce;
 122 }
 123
 124 void __init swiotlb_exit(void);
 125 unsigned int swiotlb_max_segment(void);
 126 size_t swiotlb_max_mapping_size(struct device *dev);
 127 bool is_swiotlb_active(struct device *dev);
 128 void __init swiotlb_adjust_size(unsigned long size);
 129 #else
 130 #define swiotlb_force SWIOTLB_NO_FORCE
 131 static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 132 {
 133         return false;
 134 }
 135 static inline bool is_swiotlb_force_bounce(struct device *dev)
 136 {
 137         return false;
 138 }
 139 static inline void swiotlb_exit(void)
 140 {
 141 }
 142 static inline unsigned int swiotlb_max_segment(void)
 143 {
 144         return 0;
 145 }
 146 static inline size_t swiotlb_max_mapping_size(struct device *dev)
 147 {
 148         return SIZE_MAX;
 149 }
 150
 151 static inline bool is_swiotlb_active(struct device *dev)
 152 {
 153         return false;
 154 }
 155
 156 static inline void swiotlb_adjust_size(unsigned long size)
 157 {
 158 }
 159 #endif /* CONFIG_SWIOTLB */
 160
 161 extern void swiotlb_print_info(void);
 162 extern void swiotlb_set_max_segment(unsigned int);
 163
 164 #ifdef CONFIG_DMA_RESTRICTED_POOL
 165 struct page *swiotlb_alloc(struct device *dev, size_t size);
 166 bool swiotlb_free(struct device *dev, struct page *page, size_t size);
 167
 168 static inline bool is_swiotlb_for_alloc(struct device *dev)
 169 {
 170         return dev->dma_io_tlb_mem->for_alloc;
 171 }
 172 #else
 173 static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
 174 {
 175         return NULL;
 176 }
 177 static inline bool swiotlb_free(struct device *dev, struct page *page,
 178                                 size_t size)
 179 {
 180         return false;
 181 }
 182 static inline bool is_swiotlb_for_alloc(struct device *dev)
 183 {
 184         return false;
 185 }
 186 #endif /* CONFIG_DMA_RESTRICTED_POOL */
 187
 188 #endif /* __LINUX_SWIOTLB_H */