include/linux/iova.h

   1 /*
   2  * Copyright (c) 2006, Intel Corporation.
   3  *
   4  * This file is released under the GPLv2.
   5  *
   6  * Copyright (C) 2006-2008 Intel Corporation
   7  * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
   8  *
   9  */
  10
  11 #ifndef _IOVA_H_
  12 #define _IOVA_H_
  13
  14 #include <linux/types.h>
  15 #include <linux/kernel.h>
  16 #include <linux/rbtree.h>
  17 #include <linux/dma-mapping.h>
  18
  19 /* iova structure */
  20 struct iova {
  21         struct rb_node  node;
  22         unsigned long   pfn_hi; /* Highest allocated pfn */
  23         unsigned long   pfn_lo; /* Lowest allocated pfn */
  24 };
  25
  26 struct iova_magazine;
  27 struct iova_cpu_rcache;
  28
  29 #define IOVA_RANGE_CACHE_MAX_SIZE 6     /* log of max cached IOVA range size (in pages) */
  30 #define MAX_GLOBAL_MAGS 32      /* magazines per bin */
  31
  32 struct iova_rcache {
  33         spinlock_t lock;
  34         unsigned long depot_size;
  35         struct iova_magazine *depot[MAX_GLOBAL_MAGS];
  36         struct iova_cpu_rcache __percpu *cpu_rcaches;
  37 };
  38
  39 /* holds all the iova translations for a domain */
  40 struct iova_domain {
  41         spinlock_t      iova_rbtree_lock; /* Lock to protect update of rbtree */
  42         struct rb_root  rbroot;         /* iova domain rbtree root */
  43         struct rb_node  *cached32_node; /* Save last alloced node */
  44         unsigned long   granule;        /* pfn granularity for this domain */
  45         unsigned long   start_pfn;      /* Lower limit for this domain */
  46         unsigned long   dma_32bit_pfn;
  47         struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];  /* IOVA range caches */
  48 };
  49
  50 static inline unsigned long iova_size(struct iova *iova)
  51 {
  52         return iova->pfn_hi - iova->pfn_lo + 1;
  53 }
  54
  55 static inline unsigned long iova_shift(struct iova_domain *iovad)
  56 {
  57         return __ffs(iovad->granule);
  58 }
  59
  60 static inline unsigned long iova_mask(struct iova_domain *iovad)
  61 {
  62         return iovad->granule - 1;
  63 }
  64
  65 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
  66 {
  67         return iova & iova_mask(iovad);
  68 }
  69
  70 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
  71 {
  72         return ALIGN(size, iovad->granule);
  73 }
  74
  75 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
  76 {
  77         return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
  78 }
  79
  80 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
  81 {
  82         return iova >> iova_shift(iovad);
  83 }
  84
  85 #if IS_ENABLED(CONFIG_IOMMU_IOVA)
  86 int iova_cache_get(void);
  87 void iova_cache_put(void);
  88
  89 struct iova *alloc_iova_mem(void);
  90 void free_iova_mem(struct iova *iova);
  91 void free_iova(struct iova_domain *iovad, unsigned long pfn);
  92 void __free_iova(struct iova_domain *iovad, struct iova *iova);
  93 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
  94         unsigned long limit_pfn,
  95         bool size_aligned);
  96 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
  97                     unsigned long size);
  98 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
  99                               unsigned long limit_pfn);
 100 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 101         unsigned long pfn_hi);
 102 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
 103 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 104         unsigned long start_pfn, unsigned long pfn_32bit);
 105 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
 106 void put_iova_domain(struct iova_domain *iovad);
 107 struct iova *split_and_remove_iova(struct iova_domain *iovad,
 108         struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
 109 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
 110 #else
 111 static inline int iova_cache_get(void)
 112 {
 113         return -ENOTSUPP;
 114 }
 115
 116 static inline void iova_cache_put(void)
 117 {
 118 }
 119
 120 static inline struct iova *alloc_iova_mem(void)
 121 {
 122         return NULL;
 123 }
 124
 125 static inline void free_iova_mem(struct iova *iova)
 126 {
 127 }
 128
 129 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
 130 {
 131 }
 132
 133 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
 134 {
 135 }
 136
 137 static inline struct iova *alloc_iova(struct iova_domain *iovad,
 138                                       unsigned long size,
 139                                       unsigned long limit_pfn,
 140                                       bool size_aligned)
 141 {
 142         return NULL;
 143 }
 144
 145 static inline void free_iova_fast(struct iova_domain *iovad,
 146                                   unsigned long pfn,
 147                                   unsigned long size)
 148 {
 149 }
 150
 151 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
 152                                             unsigned long size,
 153                                             unsigned long limit_pfn)
 154 {
 155         return 0;
 156 }
 157
 158 static inline struct iova *reserve_iova(struct iova_domain *iovad,
 159                                         unsigned long pfn_lo,
 160                                         unsigned long pfn_hi)
 161 {
 162         return NULL;
 163 }
 164
 165 static inline void copy_reserved_iova(struct iova_domain *from,
 166                                       struct iova_domain *to)
 167 {
 168 }
 169
 170 static inline void init_iova_domain(struct iova_domain *iovad,
 171                                     unsigned long granule,
 172                                     unsigned long start_pfn,
 173                                     unsigned long pfn_32bit)
 174 {
 175 }
 176
 177 static inline struct iova *find_iova(struct iova_domain *iovad,
 178                                      unsigned long pfn)
 179 {
 180         return NULL;
 181 }
 182
 183 static inline void put_iova_domain(struct iova_domain *iovad)
 184 {
 185 }
 186
 187 static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
 188                                                  struct iova *iova,
 189                                                  unsigned long pfn_lo,
 190                                                  unsigned long pfn_hi)
 191 {
 192         return NULL;
 193 }
 194
 195 static inline void free_cpu_cached_iovas(unsigned int cpu,
 196                                          struct iova_domain *iovad)
 197 {
 198 }
 199 #endif
 200
 201 #endif