include/rdma/rdmavt_mr.h

   1 #ifndef DEF_RDMAVT_INCMR_H
   2 #define DEF_RDMAVT_INCMR_H
   3
   4 /*
   5  * Copyright(c) 2016 Intel Corporation.
   6  *
   7  * This file is provided under a dual BSD/GPLv2 license.  When using or
   8  * redistributing this file, you may do so under either license.
   9  *
  10  * GPL LICENSE SUMMARY
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of version 2 of the GNU General Public License as
  14  * published by the Free Software Foundation.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * General Public License for more details.
  20  *
  21  * BSD LICENSE
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  *
  27  *  - Redistributions of source code must retain the above copyright
  28  *    notice, this list of conditions and the following disclaimer.
  29  *  - Redistributions in binary form must reproduce the above copyright
  30  *    notice, this list of conditions and the following disclaimer in
  31  *    the documentation and/or other materials provided with the
  32  *    distribution.
  33  *  - Neither the name of Intel Corporation nor the names of its
  34  *    contributors may be used to endorse or promote products derived
  35  *    from this software without specific prior written permission.
  36  *
  37  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  38  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  39  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  40  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  41  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  43  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  44  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  45  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  46  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  47  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  48  *
  49  */
  50
  51 /*
  52  * For Memory Regions. This stuff should probably be moved into rdmavt/mr.h once
  53  * drivers no longer need access to the MR directly.
  54  */
  55
  56 /*
  57  * A segment is a linear region of low physical memory.
  58  * Used by the verbs layer.
  59  */
  60 struct rvt_seg {
  61         void *vaddr;
  62         size_t length;
  63 };
  64
  65 /* The number of rvt_segs that fit in a page. */
  66 #define RVT_SEGSZ     (PAGE_SIZE / sizeof(struct rvt_seg))
  67
  68 struct rvt_segarray {
  69         struct rvt_seg segs[RVT_SEGSZ];
  70 };
  71
  72 struct rvt_mregion {
  73         struct ib_pd *pd;       /* shares refcnt of ibmr.pd */
  74         u64 user_base;          /* User's address for this region */
  75         u64 iova;               /* IB start address of this region */
  76         size_t length;
  77         u32 lkey;
  78         u32 offset;             /* offset (bytes) to start of region */
  79         int access_flags;
  80         u32 max_segs;           /* number of rvt_segs in all the arrays */
  81         u32 mapsz;              /* size of the map array */
  82         u8  page_shift;         /* 0 - non unform/non powerof2 sizes */
  83         u8  lkey_published;     /* in global table */
  84         struct completion comp; /* complete when refcount goes to zero */
  85         atomic_t refcount;
  86         struct rvt_segarray *map[0];    /* the segments */
  87 };
  88
  89 #define RVT_MAX_LKEY_TABLE_BITS 23
  90
  91 struct rvt_lkey_table {
  92         spinlock_t lock; /* protect changes in this struct */
  93         u32 next;               /* next unused index (speeds search) */
  94         u32 gen;                /* generation count */
  95         u32 max;                /* size of the table */
  96         struct rvt_mregion __rcu **table;
  97 };
  98
  99 /*
 100  * These keep track of the copy progress within a memory region.
 101  * Used by the verbs layer.
 102  */
 103 struct rvt_sge {
 104         struct rvt_mregion *mr;
 105         void *vaddr;            /* kernel virtual address of segment */
 106         u32 sge_length;         /* length of the SGE */
 107         u32 length;             /* remaining length of the segment */
 108         u16 m;                  /* current index: mr->map[m] */
 109         u16 n;                  /* current index: mr->map[m]->segs[n] */
 110 };
 111
 112 struct rvt_sge_state {
 113         struct rvt_sge *sg_list;      /* next SGE to be used if any */
 114         struct rvt_sge sge;   /* progress state for the current SGE */
 115         u32 total_len;
 116         u8 num_sge;
 117 };
 118
 119 static inline void rvt_put_mr(struct rvt_mregion *mr)
 120 {
 121         if (unlikely(atomic_dec_and_test(&mr->refcount)))
 122                 complete(&mr->comp);
 123 }
 124
 125 static inline void rvt_get_mr(struct rvt_mregion *mr)
 126 {
 127         atomic_inc(&mr->refcount);
 128 }
 129
 130 static inline void rvt_put_ss(struct rvt_sge_state *ss)
 131 {
 132         while (ss->num_sge) {
 133                 rvt_put_mr(ss->sge.mr);
 134                 if (--ss->num_sge)
 135                         ss->sge = *ss->sg_list++;
 136         }
 137 }
 138
 139 #endif          /* DEF_RDMAVT_INCMRH */