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         struct iova     anchor;         /* rbtree lookup anchor */
  79         struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];  /* IOVA range caches */
  80
  81         iova_flush_cb   flush_cb;       /* Call-Back function to flush IOMMU
  82                                            TLBs */
  83
  84         iova_entry_dtor entry_dtor;     /* IOMMU driver specific destructor for
  85                                            iova entry */
  86
  87         struct iova_fq __percpu *fq;    /* Flush Queue */
  88
  89         atomic64_t      fq_flush_start_cnt;     /* Number of TLB flushes that
  90                                                    have been started */
  91
  92         atomic64_t      fq_flush_finish_cnt;    /* Number of TLB flushes that
  93                                                    have been finished */
  94
  95         struct timer_list fq_timer;             /* Timer to regularily empty the
  96                                                    flush-queues */
  97         atomic_t fq_timer_on;                   /* 1 when timer is active, 0
  98                                                    when not */
  99 };
 100
 101 static inline unsigned long iova_size(struct iova *iova)
 102 {
 103         return iova->pfn_hi - iova->pfn_lo + 1;
 104 }
 105
 106 static inline unsigned long iova_shift(struct iova_domain *iovad)
 107 {
 108         return __ffs(iovad->granule);
 109 }
 110
 111 static inline unsigned long iova_mask(struct iova_domain *iovad)
 112 {
 113         return iovad->granule - 1;
 114 }
 115
 116 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
 117 {
 118         return iova & iova_mask(iovad);
 119 }
 120
 121 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
 122 {
 123         return ALIGN(size, iovad->granule);
 124 }
 125
 126 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
 127 {
 128         return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
 129 }
 130
 131 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
 132 {
 133         return iova >> iova_shift(iovad);
 134 }
 135
 136 #if IS_ENABLED(CONFIG_IOMMU_IOVA)
 137 int iova_cache_get(void);
 138 void iova_cache_put(void);
 139
 140 struct iova *alloc_iova_mem(void);
 141 void free_iova_mem(struct iova *iova);
 142 void free_iova(struct iova_domain *iovad, unsigned long pfn);
 143 void __free_iova(struct iova_domain *iovad, struct iova *iova);
 144 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
 145         unsigned long limit_pfn,
 146         bool size_aligned);
 147 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
 148                     unsigned long size);
 149 void queue_iova(struct iova_domain *iovad,
 150                 unsigned long pfn, unsigned long pages,
 151                 unsigned long data);
 152 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
 153                               unsigned long limit_pfn, bool flush_rcache);
 154 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 155         unsigned long pfn_hi);
 156 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
 157 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 158         unsigned long start_pfn);
 159 int init_iova_flush_queue(struct iova_domain *iovad,
 160                           iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
 161 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
 162 void put_iova_domain(struct iova_domain *iovad);
 163 struct iova *split_and_remove_iova(struct iova_domain *iovad,
 164         struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
 165 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
 166 #else
 167 static inline int iova_cache_get(void)
 168 {
 169         return -ENOTSUPP;
 170 }
 171
 172 static inline void iova_cache_put(void)
 173 {
 174 }
 175
 176 static inline struct iova *alloc_iova_mem(void)
 177 {
 178         return NULL;
 179 }
 180
 181 static inline void free_iova_mem(struct iova *iova)
 182 {
 183 }
 184
 185 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
 186 {
 187 }
 188
 189 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
 190 {
 191 }
 192
 193 static inline struct iova *alloc_iova(struct iova_domain *iovad,
 194                                       unsigned long size,
 195                                       unsigned long limit_pfn,
 196                                       bool size_aligned)
 197 {
 198         return NULL;
 199 }
 200
 201 static inline void free_iova_fast(struct iova_domain *iovad,
 202                                   unsigned long pfn,
 203                                   unsigned long size)
 204 {
 205 }
 206
 207 static inline void queue_iova(struct iova_domain *iovad,
 208                               unsigned long pfn, unsigned long pages,
 209                               unsigned long data)
 210 {
 211 }
 212
 213 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
 214                                             unsigned long size,
 215                                             unsigned long limit_pfn,
 216                                             bool flush_rcache)
 217 {
 218         return 0;
 219 }
 220
 221 static inline struct iova *reserve_iova(struct iova_domain *iovad,
 222                                         unsigned long pfn_lo,
 223                                         unsigned long pfn_hi)
 224 {
 225         return NULL;
 226 }
 227
 228 static inline void copy_reserved_iova(struct iova_domain *from,
 229                                       struct iova_domain *to)
 230 {
 231 }
 232
 233 static inline void init_iova_domain(struct iova_domain *iovad,
 234                                     unsigned long granule,
 235                                     unsigned long start_pfn)
 236 {
 237 }
 238
 239 static inline int init_iova_flush_queue(struct iova_domain *iovad,
 240                                         iova_flush_cb flush_cb,
 241                                         iova_entry_dtor entry_dtor)
 242 {
 243         return -ENODEV;
 244 }
 245
 246 static inline struct iova *find_iova(struct iova_domain *iovad,
 247                                      unsigned long pfn)
 248 {
 249         return NULL;
 250 }
 251
 252 static inline void put_iova_domain(struct iova_domain *iovad)
 253 {
 254 }
 255
 256 static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
 257                                                  struct iova *iova,
 258                                                  unsigned long pfn_lo,
 259                                                  unsigned long pfn_hi)
 260 {
 261         return NULL;
 262 }
 263
 264 static inline void free_cpu_cached_iovas(unsigned int cpu,
 265                                          struct iova_domain *iovad)
 266 {
 267 }
 268 #endif
 269
 270 #endif