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 #include <linux/percpu-refcount.h> 56 57 /* 58 * A segment is a linear region of low physical memory. 59 * Used by the verbs layer. 60 */ 61 struct rvt_seg { 62 void *vaddr; 63 size_t length; 64 }; 65 66 /* The number of rvt_segs that fit in a page. */ 67 #define RVT_SEGSZ (PAGE_SIZE / sizeof(struct rvt_seg)) 68 69 struct rvt_segarray { 70 struct rvt_seg segs[RVT_SEGSZ]; 71 }; 72 73 struct rvt_mregion { 74 struct ib_pd *pd; /* shares refcnt of ibmr.pd */ 75 u64 user_base; /* User's address for this region */ 76 u64 iova; /* IB start address of this region */ 77 size_t length; 78 u32 lkey; 79 u32 offset; /* offset (bytes) to start of region */ 80 int access_flags; 81 u32 max_segs; /* number of rvt_segs in all the arrays */ 82 u32 mapsz; /* size of the map array */ 83 atomic_t lkey_invalid; /* true if current lkey is invalid */ 84 u8 page_shift; /* 0 - non unform/non powerof2 sizes */ 85 u8 lkey_published; /* in global table */ 86 struct percpu_ref refcount; 87 struct completion comp; /* complete when refcount goes to zero */ 88 struct rvt_segarray *map[0]; /* the segments */ 89 }; 90 91 #define RVT_MAX_LKEY_TABLE_BITS 23 92 93 struct rvt_lkey_table { 94 /* read mostly fields */ 95 u32 max; /* size of the table */ 96 u32 shift; /* lkey/rkey shift */ 97 struct rvt_mregion __rcu **table; 98 /* writeable fields */ 99 /* protect changes in this struct */ 100 spinlock_t lock ____cacheline_aligned_in_smp; 101 u32 next; /* next unused index (speeds search) */ 102 u32 gen; /* generation count */ 103 }; 104 105 /* 106 * These keep track of the copy progress within a memory region. 107 * Used by the verbs layer. 108 */ 109 struct rvt_sge { 110 struct rvt_mregion *mr; 111 void *vaddr; /* kernel virtual address of segment */ 112 u32 sge_length; /* length of the SGE */ 113 u32 length; /* remaining length of the segment */ 114 u16 m; /* current index: mr->map[m] */ 115 u16 n; /* current index: mr->map[m]->segs[n] */ 116 }; 117 118 struct rvt_sge_state { 119 struct rvt_sge *sg_list; /* next SGE to be used if any */ 120 struct rvt_sge sge; /* progress state for the current SGE */ 121 u32 total_len; 122 u8 num_sge; 123 }; 124 125 static inline void rvt_put_mr(struct rvt_mregion *mr) 126 { 127 percpu_ref_put(&mr->refcount); 128 } 129 130 static inline void rvt_get_mr(struct rvt_mregion *mr) 131 { 132 percpu_ref_get(&mr->refcount); 133 } 134 135 static inline void rvt_put_ss(struct rvt_sge_state *ss) 136 { 137 while (ss->num_sge) { 138 rvt_put_mr(ss->sge.mr); 139 if (--ss->num_sge) 140 ss->sge = *ss->sg_list++; 141 } 142 } 143 144 static inline u32 rvt_get_sge_length(struct rvt_sge *sge, u32 length) 145 { 146 u32 len = sge->length; 147 148 if (len > length) 149 len = length; 150 if (len > sge->sge_length) 151 len = sge->sge_length; 152 153 return len; 154 } 155 156 static inline void rvt_update_sge(struct rvt_sge_state *ss, u32 length, 157 bool release) 158 { 159 struct rvt_sge *sge = &ss->sge; 160 161 sge->vaddr += length; 162 sge->length -= length; 163 sge->sge_length -= length; 164 if (sge->sge_length == 0) { 165 if (release) 166 rvt_put_mr(sge->mr); 167 if (--ss->num_sge) 168 *sge = *ss->sg_list++; 169 } else if (sge->length == 0 && sge->mr->lkey) { 170 if (++sge->n >= RVT_SEGSZ) { 171 if (++sge->m >= sge->mr->mapsz) 172 return; 173 sge->n = 0; 174 } 175 sge->vaddr = sge->mr->map[sge->m]->segs[sge->n].vaddr; 176 sge->length = sge->mr->map[sge->m]->segs[sge->n].length; 177 } 178 } 179 180 static inline void rvt_skip_sge(struct rvt_sge_state *ss, u32 length, 181 bool release) 182 { 183 struct rvt_sge *sge = &ss->sge; 184 185 while (length) { 186 u32 len = rvt_get_sge_length(sge, length); 187 188 WARN_ON_ONCE(len == 0); 189 rvt_update_sge(ss, len, release); 190 length -= len; 191 } 192 } 193 194 #endif /* DEF_RDMAVT_INCMRH */ 195