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/dma-mapping.h>
  16
  17 /* iova structure */
  18 struct iova {
  19         struct rb_node  node;
  20         unsigned long   pfn_hi; /* Highest allocated pfn */
  21         unsigned long   pfn_lo; /* Lowest allocated pfn */
  22 };
  23
  24
  25 struct iova_rcache;
  26
  27 /* holds all the iova translations for a domain */
  28 struct iova_domain {
  29         spinlock_t      iova_rbtree_lock; /* Lock to protect update of rbtree */
  30         struct rb_root  rbroot;         /* iova domain rbtree root */
  31         struct rb_node  *cached_node;   /* Save last alloced node */
  32         struct rb_node  *cached32_node; /* Save last 32-bit alloced node */
  33         unsigned long   granule;        /* pfn granularity for this domain */
  34         unsigned long   start_pfn;      /* Lower limit for this domain */
  35         unsigned long   dma_32bit_pfn;
  36         unsigned long   max32_alloc_size; /* Size of last failed allocation */
  37         struct iova     anchor;         /* rbtree lookup anchor */
  38
  39         struct iova_rcache      *rcaches;
  40         struct hlist_node       cpuhp_dead;
  41 };
  42
  43 static inline unsigned long iova_size(struct iova *iova)
  44 {
  45         return iova->pfn_hi - iova->pfn_lo + 1;
  46 }
  47
  48 static inline unsigned long iova_shift(struct iova_domain *iovad)
  49 {
  50         return __ffs(iovad->granule);
  51 }
  52
  53 static inline unsigned long iova_mask(struct iova_domain *iovad)
  54 {
  55         return iovad->granule - 1;
  56 }
  57
  58 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
  59 {
  60         return iova & iova_mask(iovad);
  61 }
  62
  63 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
  64 {
  65         return ALIGN(size, iovad->granule);
  66 }
  67
  68 static inline size_t iova_align_down(struct iova_domain *iovad, size_t size)
  69 {
  70         return ALIGN_DOWN(size, iovad->granule);
  71 }
  72
  73 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
  74 {
  75         return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
  76 }
  77
  78 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
  79 {
  80         return iova >> iova_shift(iovad);
  81 }
  82
  83 #if IS_REACHABLE(CONFIG_IOMMU_IOVA)
  84 int iova_cache_get(void);
  85 void iova_cache_put(void);
  86
  87 unsigned long iova_rcache_range(void);
  88
  89 void free_iova(struct iova_domain *iovad, unsigned long pfn);
  90 void __free_iova(struct iova_domain *iovad, struct iova *iova);
  91 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
  92         unsigned long limit_pfn,
  93         bool size_aligned);
  94 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
  95                     unsigned long size);
  96 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
  97                               unsigned long limit_pfn, bool flush_rcache);
  98 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
  99         unsigned long pfn_hi);
 100 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 101         unsigned long start_pfn);
 102 int iova_domain_init_rcaches(struct iova_domain *iovad);
 103 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
 104 void put_iova_domain(struct iova_domain *iovad);
 105 #else
 106 static inline int iova_cache_get(void)
 107 {
 108         return -ENOTSUPP;
 109 }
 110
 111 static inline void iova_cache_put(void)
 112 {
 113 }
 114
 115 static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
 116 {
 117 }
 118
 119 static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
 120 {
 121 }
 122
 123 static inline struct iova *alloc_iova(struct iova_domain *iovad,
 124                                       unsigned long size,
 125                                       unsigned long limit_pfn,
 126                                       bool size_aligned)
 127 {
 128         return NULL;
 129 }
 130
 131 static inline void free_iova_fast(struct iova_domain *iovad,
 132                                   unsigned long pfn,
 133                                   unsigned long size)
 134 {
 135 }
 136
 137 static inline unsigned long alloc_iova_fast(struct iova_domain *iovad,
 138                                             unsigned long size,
 139                                             unsigned long limit_pfn,
 140                                             bool flush_rcache)
 141 {
 142         return 0;
 143 }
 144
 145 static inline struct iova *reserve_iova(struct iova_domain *iovad,
 146                                         unsigned long pfn_lo,
 147                                         unsigned long pfn_hi)
 148 {
 149         return NULL;
 150 }
 151
 152 static inline void init_iova_domain(struct iova_domain *iovad,
 153                                     unsigned long granule,
 154                                     unsigned long start_pfn)
 155 {
 156 }
 157
 158 static inline struct iova *find_iova(struct iova_domain *iovad,
 159                                      unsigned long pfn)
 160 {
 161         return NULL;
 162 }
 163
 164 static inline void put_iova_domain(struct iova_domain *iovad)
 165 {
 166 }
 167
 168 #endif
 169
 170 #endif