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 bool rvt_ss_has_lkey(struct rvt_sge_state *ss, u32 lkey);
195 bool rvt_mr_has_lkey(struct rvt_mregion *mr, u32 lkey);
196
197 #endif /* DEF_RDMAVT_INCMRH */