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/atomic.h>
  18 #include <linux/dma-mapping.h>
  19
  20 /* iova structure */
  21 struct iova {
  22         struct rb_node  node;
  23         unsigned long   pfn_hi; /* Highest allocated pfn */
  24         unsigned long   pfn_lo; /* Lowest allocated pfn */
  25 };
  26
  27 struct iova_magazine;
  28 struct iova_cpu_rcache;
  29
  30 #define IOVA_RANGE_CACHE_MAX_SIZE 6     /* log of max cached IOVA range size (in pages) */
  31 #define MAX_GLOBAL_MAGS 32      /* magazines per bin */
  32
  33 struct iova_rcache {
  34         spinlock_t lock;
  35         unsigned long depot_size;
  36         struct iova_magazine *depot[MAX_GLOBAL_MAGS];
  37         struct iova_cpu_rcache __percpu *cpu_rcaches;
  38 };
  39
  40 struct iova_domain;
  41
  42 /* Call-Back from IOVA code into IOMMU drivers */
  43 typedef void (* iova_flush_cb)(struct iova_domain *domain);
  44
  45 /* Destructor for per-entry data */
  46 typedef void (* iova_entry_dtor)(unsigned long data);
  47
  48 /* Number of entries per Flush Queue */
  49 #define IOVA_FQ_SIZE    256
  50
  51 /* Timeout (in ms) after which entries are flushed from the Flush-Queue */
  52 #define IOVA_FQ_TIMEOUT 10
  53
  54 /* Flush Queue entry for defered flushing */
  55 struct iova_fq_entry {
  56         unsigned long iova_pfn;
  57         unsigned long pages;
  58         unsigned long data;
  59         u64 counter; /* Flush counter when this entrie was added */
  60 };
  61
  62 /* Per-CPU Flush Queue structure */
  63 struct iova_fq {
  64         struct iova_fq_entry entries[IOVA_FQ_SIZE];
  65         unsigned head, tail;
  66         spinlock_t lock;
  67 };
  68
  69 /* holds all the iova translations for a domain */
  70 struct iova_domain {
  71         spinlock_t      iova_rbtree_lock; /* Lock to protect update of rbtree */
  72         struct rb_root  rbroot;         /* iova domain rbtree root */
  73         struct rb_node  *cached_node;   /* Save last alloced node */
  74         struct rb_node  *cached32_node; /* Save last 32-bit alloced node */
  75         unsigned long   granule;        /* pfn granularity for this domain */
  76         unsigned long   start_pfn;      /* Lower limit for this domain */
  77         unsigned long   dma_32bit_pfn;
  78         unsigned long   max32_alloc_size; /* Size of last failed allocation */
  79         struct iova     anchor;         /* rbtree lookup anchor */
  80         struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];  /* IOVA range caches */
  81
  82         iova_flush_cb   flush_cb;       /* Call-Back function to flush IOMMU
  83                                            TLBs */
  84
  85         iova_entry_dtor entry_dtor;     /* IOMMU driver specific destructor for
  86                                            iova entry */
  87
  88         struct iova_fq __percpu *fq;    /* Flush Queue */
  89
  90         atomic64_t      fq_flush_start_cnt;     /* Number of TLB flushes that
  91                                                    have been started */
  92
  93         atomic64_t      fq_flush_finish_cnt;    /* Number of TLB flushes that
  94                                                    have been finished */
  95
  96         struct timer_list fq_timer;             /* Timer to regularily empty the
  97                                                    flush-queues */
  98         atomic_t fq_timer_on;                   /* 1 when timer is active, 0
  99                                                    when not */
 100 };
 101
 102 static inline unsigned long iova_size(struct iova *iova)
 103 {
 104         return iova->pfn_hi - iova->pfn_lo + 1;
 105 }
 106
 107 static inline unsigned long iova_shift(struct iova_domain *iovad)
 108 {
 109         return __ffs(iovad->granule);
 110 }
 111
 112 static inline unsigned long iova_mask(struct iova_domain *iovad)
 113 {
 114         return iovad->granule - 1;
 115 }
 116
 117 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
 118 {
 119         return iova & iova_mask(iovad);
 120 }
 121
 122 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
 123 {
 124         return ALIGN(size, iovad->granule);
 125 }
 126
 127 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
 128 {
 129         return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
 130 }
 131
 132 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
 133 {
 134         return iova >> iova_shift(iovad);
 135 }
 136
 137 #if IS_ENABLED(CONFIG_IOMMU_IOVA)
 138 int iova_cache_get(void);
 139 void iova_cache_put(void);
 140
 141 struct iova *alloc_iova_mem(void);
 142 void free_iova_mem(struct iova *iova);
 143 void free_iova(struct iova_domain *iovad, unsigned long pfn);
 144 void __free_iova(struct iova_domain *iovad, struct iova *iova);
 145 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
 146         unsigned long limit_pfn,
 147         bool size_aligned);
 148 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
 149                     unsigned long size);
 150 void queue_iova(struct iova_domain *iovad,
 151                 unsigned long pfn, unsigned long pages,
 152                 unsigned long data);
 153 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
 154                               unsigned long limit_pfn, bool flush_rcache);
 155 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 156         unsigned long pfn_hi);
 157 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
 158 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 159         unsigned long start_pfn);
 160 int init_iova_flush_queue(struct iova_domain *iovad,
 161                           iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
 162 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
 163 void put_iova_domain(struct iova_domain *iovad);
 164 struct iova *split_and_remove_iova(struct iova_domain *iovad,
 165         struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
 166 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
 167 #else
 168 static inline int iova_cache_get(void)
 169 {
 170         return -ENOTSUPP;
 171 }
 172
 173 static inline void iova_cache_put(void)
 174 {
 175 }
 176
 177 static inline struct iova *alloc_iova_mem(void)
 178 {
 179         return NULL;
 180 }
 181
 182 static inline void free_iova_mem(struct iova *iova)
 183 {
 184 }
 185
 186 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
 187 {
 188 }
 189
 190 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
 191 {
 192 }
 193
 194 static inline struct iova *alloc_iova(struct iova_domain *iovad,
 195                                       unsigned long size,
 196                                       unsigned long limit_pfn,
 197                                       bool size_aligned)
 198 {
 199         return NULL;
 200 }
 201
 202 static inline void free_iova_fast(struct iova_domain *iovad,
 203                                   unsigned long pfn,
 204                                   unsigned long size)
 205 {
 206 }
 207
 208 static inline void queue_iova(struct iova_domain *iovad,
 209                               unsigned long pfn, unsigned long pages,
 210                               unsigned long data)
 211 {
 212 }
 213
 214 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
 215                                             unsigned long size,
 216                                             unsigned long limit_pfn,
 217                                             bool flush_rcache)
 218 {
 219         return 0;
 220 }
 221
 222 static inline struct iova *reserve_iova(struct iova_domain *iovad,
 223                                         unsigned long pfn_lo,
 224                                         unsigned long pfn_hi)
 225 {
 226         return NULL;
 227 }
 228
 229 static inline void copy_reserved_iova(struct iova_domain *from,
 230                                       struct iova_domain *to)
 231 {
 232 }
 233
 234 static inline void init_iova_domain(struct iova_domain *iovad,
 235                                     unsigned long granule,
 236                                     unsigned long start_pfn)
 237 {
 238 }
 239
 240 static inline int init_iova_flush_queue(struct iova_domain *iovad,
 241                                         iova_flush_cb flush_cb,
 242                                         iova_entry_dtor entry_dtor)
 243 {
 244         return -ENODEV;
 245 }
 246
 247 static inline struct iova *find_iova(struct iova_domain *iovad,
 248                                      unsigned long pfn)
 249 {
 250         return NULL;
 251 }
 252
 253 static inline void put_iova_domain(struct iova_domain *iovad)
 254 {
 255 }
 256
 257 static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
 258                                                  struct iova *iova,
 259                                                  unsigned long pfn_lo,
 260                                                  unsigned long pfn_hi)
 261 {
 262         return NULL;
 263 }
 264
 265 static inline void free_cpu_cached_iovas(unsigned int cpu,
 266                                          struct iova_domain *iovad)
 267 {
 268 }
 269 #endif
 270
 271 #endif