rdmavt_mr.h revision 331769 
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	atomic_t lkey_invalid;	/* true if current lkey is invalid */
85	struct completion comp; /* complete when refcount goes to zero */
86	atomic_t refcount;
87	struct rvt_segarray *map[0];    /* the segments */
88};
89
90#define RVT_MAX_LKEY_TABLE_BITS 23
91
92struct rvt_lkey_table {
93	spinlock_t lock; /* protect changes in this struct */
94	u32 next;               /* next unused index (speeds search) */
95	u32 gen;                /* generation count */
96	u32 max;                /* size of the table */
97	struct rvt_mregion __rcu **table;
98};
99
100/*
101 * These keep track of the copy progress within a memory region.
102 * Used by the verbs layer.
103 */
104struct rvt_sge {
105	struct rvt_mregion *mr;
106	void *vaddr;            /* kernel virtual address of segment */
107	u32 sge_length;         /* length of the SGE */
108	u32 length;             /* remaining length of the segment */
109	u16 m;                  /* current index: mr->map[m] */
110	u16 n;                  /* current index: mr->map[m]->segs[n] */
111};
112
113struct rvt_sge_state {
114	struct rvt_sge *sg_list;      /* next SGE to be used if any */
115	struct rvt_sge sge;   /* progress state for the current SGE */
116	u32 total_len;
117	u8 num_sge;
118};
119
120static inline void rvt_put_mr(struct rvt_mregion *mr)
121{
122	if (unlikely(atomic_dec_and_test(&mr->refcount)))
123		complete(&mr->comp);
124}
125
126static inline void rvt_get_mr(struct rvt_mregion *mr)
127{
128	atomic_inc(&mr->refcount);
129}
130
131static inline void rvt_put_ss(struct rvt_sge_state *ss)
132{
133	while (ss->num_sge) {
134		rvt_put_mr(ss->sge.mr);
135		if (--ss->num_sge)
136			ss->sge = *ss->sg_list++;
137	}
138}
139
140#endif          /* DEF_RDMAVT_INCMRH */
141