include/linux/iova.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (c) 2006, Intel Corporation.
   4  *
   5  * Copyright (C) 2006-2008 Intel Corporation
   6  * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
   7  */
   8
   9 #ifndef _IOVA_H_
  10 #define _IOVA_H_
  11
  12 #include <linux/types.h>
  13 #include <linux/kernel.h>
  14 #include <linux/rbtree.h>
  15 #include <linux/atomic.h>
  16 #include <linux/dma-mapping.h>
  17
  18 /* iova structure */
  19 struct iova {
  20         struct rb_node  node;
  21         unsigned long   pfn_hi; /* Highest allocated pfn */
  22         unsigned long   pfn_lo; /* Lowest allocated pfn */
  23 };
  24
  25 struct iova_magazine;
  26 struct iova_cpu_rcache;
  27
  28 #define IOVA_RANGE_CACHE_MAX_SIZE 6     /* log of max cached IOVA range size (in pages) */
  29 #define MAX_GLOBAL_MAGS 32      /* magazines per bin */
  30
  31 struct iova_rcache {
  32         spinlock_t lock;
  33         unsigned long depot_size;
  34         struct iova_magazine *depot[MAX_GLOBAL_MAGS];
  35         struct iova_cpu_rcache __percpu *cpu_rcaches;
  36 };
  37
  38 struct iova_domain;
  39
  40 /* Call-Back from IOVA code into IOMMU drivers */
  41 typedef void (* iova_flush_cb)(struct iova_domain *domain);
  42
  43 /* Destructor for per-entry data */
  44 typedef void (* iova_entry_dtor)(unsigned long data);
  45
  46 /* Number of entries per Flush Queue */
  47 #define IOVA_FQ_SIZE    256
  48
  49 /* Timeout (in ms) after which entries are flushed from the Flush-Queue */
  50 #define IOVA_FQ_TIMEOUT 10
  51
  52 /* Flush Queue entry for defered flushing */
  53 struct iova_fq_entry {
  54         unsigned long iova_pfn;
  55         unsigned long pages;
  56         unsigned long data;
  57         u64 counter; /* Flush counter when this entrie was added */
  58 };
  59
  60 /* Per-CPU Flush Queue structure */
  61 struct iova_fq {
  62         struct iova_fq_entry entries[IOVA_FQ_SIZE];
  63         unsigned head, tail;
  64         spinlock_t lock;
  65 };
  66
  67 /* holds all the iova translations for a domain */
  68 struct iova_domain {
  69         spinlock_t      iova_rbtree_lock; /* Lock to protect update of rbtree */
  70         struct rb_root  rbroot;         /* iova domain rbtree root */
  71         struct rb_node  *cached_node;   /* Save last alloced node */
  72         struct rb_node  *cached32_node; /* Save last 32-bit alloced node */
  73         unsigned long   granule;        /* pfn granularity for this domain */
  74         unsigned long   start_pfn;      /* Lower limit for this domain */
  75         unsigned long   dma_32bit_pfn;
  76         unsigned long   max32_alloc_size; /* Size of last failed allocation */
  77         struct iova_fq __percpu *fq;    /* Flush Queue */
  78
  79         atomic64_t      fq_flush_start_cnt;     /* Number of TLB flushes that
  80                                                    have been started */
  81
  82         atomic64_t      fq_flush_finish_cnt;    /* Number of TLB flushes that
  83                                                    have been finished */
  84
  85         struct iova     anchor;         /* rbtree lookup anchor */
  86         struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];  /* IOVA range caches */
  87
  88         iova_flush_cb   flush_cb;       /* Call-Back function to flush IOMMU
  89                                            TLBs */
  90
  91         iova_entry_dtor entry_dtor;     /* IOMMU driver specific destructor for
  92                                            iova entry */
  93
  94         struct timer_list fq_timer;             /* Timer to regularily empty the
  95                                                    flush-queues */
  96         atomic_t fq_timer_on;                   /* 1 when timer is active, 0
  97                                                    when not */
  98         struct hlist_node       cpuhp_dead;
  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 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, bool flush_rcache);
 152 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 153         unsigned long pfn_hi);
 154 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 155         unsigned long start_pfn);
 156 int init_iova_flush_queue(struct iova_domain *iovad,
 157                           iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
 158 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
 159 void put_iova_domain(struct iova_domain *iovad);
 160 #else
 161 static inline int iova_cache_get(void)
 162 {
 163         return -ENOTSUPP;
 164 }
 165
 166 static inline void iova_cache_put(void)
 167 {
 168 }
 169
 170 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
 171 {
 172 }
 173
 174 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
 175 {
 176 }
 177
 178 static inline struct iova *alloc_iova(struct iova_domain *iovad,
 179                                       unsigned long size,
 180                                       unsigned long limit_pfn,
 181                                       bool size_aligned)
 182 {
 183         return NULL;
 184 }
 185
 186 static inline void free_iova_fast(struct iova_domain *iovad,
 187                                   unsigned long pfn,
 188                                   unsigned long size)
 189 {
 190 }
 191
 192 static inline void queue_iova(struct iova_domain *iovad,
 193                               unsigned long pfn, unsigned long pages,
 194                               unsigned long data)
 195 {
 196 }
 197
 198 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
 199                                             unsigned long size,
 200                                             unsigned long limit_pfn,
 201                                             bool flush_rcache)
 202 {
 203         return 0;
 204 }
 205
 206 static inline struct iova *reserve_iova(struct iova_domain *iovad,
 207                                         unsigned long pfn_lo,
 208                                         unsigned long pfn_hi)
 209 {
 210         return NULL;
 211 }
 212
 213 static inline void init_iova_domain(struct iova_domain *iovad,
 214                                     unsigned long granule,
 215                                     unsigned long start_pfn)
 216 {
 217 }
 218
 219 static inline int init_iova_flush_queue(struct iova_domain *iovad,
 220                                         iova_flush_cb flush_cb,
 221                                         iova_entry_dtor entry_dtor)
 222 {
 223         return -ENODEV;
 224 }
 225
 226 static inline struct iova *find_iova(struct iova_domain *iovad,
 227                                      unsigned long pfn)
 228 {
 229         return NULL;
 230 }
 231
 232 static inline void put_iova_domain(struct iova_domain *iovad)
 233 {
 234 }
 235
 236 #endif
 237
 238 #endif