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  *cached32_node; /* Save last alloced node */
  74         unsigned long   granule;        /* pfn granularity for this domain */
  75         unsigned long   start_pfn;      /* Lower limit for this domain */
  76         unsigned long   dma_32bit_pfn;
  77         struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];  /* IOVA range caches */
  78
  79         iova_flush_cb   flush_cb;       /* Call-Back function to flush IOMMU
  80                                            TLBs */
  81
  82         iova_entry_dtor entry_dtor;     /* IOMMU driver specific destructor for
  83                                            iova entry */
  84
  85         struct iova_fq __percpu *fq;    /* Flush Queue */
  86
  87         atomic64_t      fq_flush_start_cnt;     /* Number of TLB flushes that
  88                                                    have been started */
  89
  90         atomic64_t      fq_flush_finish_cnt;    /* Number of TLB flushes that
  91                                                    have been finished */
  92
  93         struct timer_list fq_timer;             /* Timer to regularily empty the
  94                                                    flush-queues */
  95         atomic_t fq_timer_on;                   /* 1 when timer is active, 0
  96                                                    when not */
  97 };
  98
  99 static inline unsigned long iova_size(struct iova *iova)
 100 {
 101         return iova->pfn_hi - iova->pfn_lo + 1;
 102 }
 103
 104 static inline unsigned long iova_shift(struct iova_domain *iovad)
 105 {
 106         return __ffs(iovad->granule);
 107 }
 108
 109 static inline unsigned long iova_mask(struct iova_domain *iovad)
 110 {
 111         return iovad->granule - 1;
 112 }
 113
 114 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
 115 {
 116         return iova & iova_mask(iovad);
 117 }
 118
 119 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
 120 {
 121         return ALIGN(size, iovad->granule);
 122 }
 123
 124 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
 125 {
 126         return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
 127 }
 128
 129 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
 130 {
 131         return iova >> iova_shift(iovad);
 132 }
 133
 134 #if IS_ENABLED(CONFIG_IOMMU_IOVA)
 135 int iova_cache_get(void);
 136 void iova_cache_put(void);
 137
 138 struct iova *alloc_iova_mem(void);
 139 void free_iova_mem(struct iova *iova);
 140 void free_iova(struct iova_domain *iovad, unsigned long pfn);
 141 void __free_iova(struct iova_domain *iovad, struct iova *iova);
 142 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
 143         unsigned long limit_pfn,
 144         bool size_aligned);
 145 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
 146                     unsigned long size);
 147 void queue_iova(struct iova_domain *iovad,
 148                 unsigned long pfn, unsigned long pages,
 149                 unsigned long data);
 150 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
 151                               unsigned long limit_pfn);
 152 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 153         unsigned long pfn_hi);
 154 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
 155 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 156         unsigned long start_pfn, unsigned long pfn_32bit);
 157 int init_iova_flush_queue(struct iova_domain *iovad,
 158                           iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
 159 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
 160 void put_iova_domain(struct iova_domain *iovad);
 161 struct iova *split_and_remove_iova(struct iova_domain *iovad,
 162         struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
 163 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
 164 #else
 165 static inline int iova_cache_get(void)
 166 {
 167         return -ENOTSUPP;
 168 }
 169
 170 static inline void iova_cache_put(void)
 171 {
 172 }
 173
 174 static inline struct iova *alloc_iova_mem(void)
 175 {
 176         return NULL;
 177 }
 178
 179 static inline void free_iova_mem(struct iova *iova)
 180 {
 181 }
 182
 183 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
 184 {
 185 }
 186
 187 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
 188 {
 189 }
 190
 191 static inline struct iova *alloc_iova(struct iova_domain *iovad,
 192                                       unsigned long size,
 193                                       unsigned long limit_pfn,
 194                                       bool size_aligned)
 195 {
 196         return NULL;
 197 }
 198
 199 static inline void free_iova_fast(struct iova_domain *iovad,
 200                                   unsigned long pfn,
 201                                   unsigned long size)
 202 {
 203 }
 204
 205 static inline void queue_iova(struct iova_domain *iovad,
 206                               unsigned long pfn, unsigned long pages,
 207                               unsigned long data)
 208 {
 209 }
 210
 211 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
 212                                             unsigned long size,
 213                                             unsigned long limit_pfn)
 214 {
 215         return 0;
 216 }
 217
 218 static inline struct iova *reserve_iova(struct iova_domain *iovad,
 219                                         unsigned long pfn_lo,
 220                                         unsigned long pfn_hi)
 221 {
 222         return NULL;
 223 }
 224
 225 static inline void copy_reserved_iova(struct iova_domain *from,
 226                                       struct iova_domain *to)
 227 {
 228 }
 229
 230 static inline void init_iova_domain(struct iova_domain *iovad,
 231                                     unsigned long granule,
 232                                     unsigned long start_pfn,
 233                                     unsigned long pfn_32bit)
 234 {
 235 }
 236
 237 static inline int init_iova_flush_queue(struct iova_domain *iovad,
 238                                         iova_flush_cb flush_cb,
 239                                         iova_entry_dtor entry_dtor)
 240 {
 241         return -ENODEV;
 242 }
 243
 244 static inline struct iova *find_iova(struct iova_domain *iovad,
 245                                      unsigned long pfn)
 246 {
 247         return NULL;
 248 }
 249
 250 static inline void put_iova_domain(struct iova_domain *iovad)
 251 {
 252 }
 253
 254 static inline struct iova *split_and_remove_iova(struct iova_domain *iovad,
 255                                                  struct iova *iova,
 256                                                  unsigned long pfn_lo,
 257                                                  unsigned long pfn_hi)
 258 {
 259         return NULL;
 260 }
 261
 262 static inline void free_cpu_cached_iovas(unsigned int cpu,
 263                                          struct iova_domain *iovad)
 264 {
 265 }
 266 #endif
 267
 268 #endif