LXR linux/include/rdma/rdmavt

   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 */
  60struct 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
  68struct rvt_segarray {
  69        struct rvt_seg segs[RVT_SEGSZ];
  70};
  71
  72struct 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
  91struct 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 */
 103struct 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
 112struct 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
 119static 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
 125static inline void rvt_get_mr(struct rvt_mregion *mr)
 126{
 127        atomic_inc(&mr->refcount);
 128}
 129
 130static 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 */
 140