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/dma-mapping.h>
  18
  19 /* iova structure */
  20 struct iova {
  21         struct rb_node  node;
  22         unsigned long   pfn_hi; /* Highest allocated pfn */
  23         unsigned long   pfn_lo; /* Lowest allocated pfn */
  24 };
  25
  26 struct iova_magazine;
  27 struct iova_cpu_rcache;
  28
  29 #define IOVA_RANGE_CACHE_MAX_SIZE 6     /* log of max cached IOVA range size (in pages) */
  30 #define MAX_GLOBAL_MAGS 32      /* magazines per bin */
  31
  32 struct iova_rcache {
  33         spinlock_t lock;
  34         unsigned long depot_size;
  35         struct iova_magazine *depot[MAX_GLOBAL_MAGS];
  36         struct iova_cpu_rcache __percpu *cpu_rcaches;
  37 };
  38
  39 /* holds all the iova translations for a domain */
  40 struct iova_domain {
  41         spinlock_t      iova_rbtree_lock; /* Lock to protect update of rbtree */
  42         struct rb_root  rbroot;         /* iova domain rbtree root */
  43         struct rb_node  *cached32_node; /* Save last alloced node */
  44         unsigned long   granule;        /* pfn granularity for this domain */
  45         unsigned long   start_pfn;      /* Lower limit for this domain */
  46         unsigned long   dma_32bit_pfn;
  47         struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE];  /* IOVA range caches */
  48 };
  49
  50 static inline unsigned long iova_size(struct iova *iova)
  51 {
  52         return iova->pfn_hi - iova->pfn_lo + 1;
  53 }
  54
  55 static inline unsigned long iova_shift(struct iova_domain *iovad)
  56 {
  57         return __ffs(iovad->granule);
  58 }
  59
  60 static inline unsigned long iova_mask(struct iova_domain *iovad)
  61 {
  62         return iovad->granule - 1;
  63 }
  64
  65 static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
  66 {
  67         return iova & iova_mask(iovad);
  68 }
  69
  70 static inline size_t iova_align(struct iova_domain *iovad, size_t size)
  71 {
  72         return ALIGN(size, iovad->granule);
  73 }
  74
  75 static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
  76 {
  77         return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
  78 }
  79
  80 static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
  81 {
  82         return iova >> iova_shift(iovad);
  83 }
  84
  85 int iova_cache_get(void);
  86 void iova_cache_put(void);
  87
  88 struct iova *alloc_iova_mem(void);
  89 void free_iova_mem(struct iova *iova);
  90 void free_iova(struct iova_domain *iovad, unsigned long pfn);
  91 void __free_iova(struct iova_domain *iovad, struct iova *iova);
  92 struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size,
  93         unsigned long limit_pfn,
  94         bool size_aligned);
  95 void free_iova_fast(struct iova_domain *iovad, unsigned long pfn,
  96                     unsigned long size);
  97 unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
  98                               unsigned long limit_pfn);
  99 struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
 100         unsigned long pfn_hi);
 101 void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
 102 void init_iova_domain(struct iova_domain *iovad, unsigned long granule,
 103         unsigned long start_pfn, unsigned long pfn_32bit);
 104 struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
 105 void put_iova_domain(struct iova_domain *iovad);
 106 struct iova *split_and_remove_iova(struct iova_domain *iovad,
 107         struct iova *iova, unsigned long pfn_lo, unsigned long pfn_hi);
 108 void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
 109
 110 #endif