xref: /openbmc/linux/include/rdma/rdmavt_mr.h (revision 8730046c)
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 	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 
92 struct rvt_lkey_table {
93 	/* read mostly fields */
94 	u32 max;                /* size of the table */
95 	u32 shift;              /* lkey/rkey shift */
96 	struct rvt_mregion __rcu **table;
97 	/* writeable fields */
98 	/* protect changes in this struct */
99 	spinlock_t lock ____cacheline_aligned_in_smp;
100 	u32 next;               /* next unused index (speeds search) */
101 	u32 gen;                /* generation count */
102 };
103 
104 /*
105  * These keep track of the copy progress within a memory region.
106  * Used by the verbs layer.
107  */
108 struct rvt_sge {
109 	struct rvt_mregion *mr;
110 	void *vaddr;            /* kernel virtual address of segment */
111 	u32 sge_length;         /* length of the SGE */
112 	u32 length;             /* remaining length of the segment */
113 	u16 m;                  /* current index: mr->map[m] */
114 	u16 n;                  /* current index: mr->map[m]->segs[n] */
115 };
116 
117 struct rvt_sge_state {
118 	struct rvt_sge *sg_list;      /* next SGE to be used if any */
119 	struct rvt_sge sge;   /* progress state for the current SGE */
120 	u32 total_len;
121 	u8 num_sge;
122 };
123 
124 static inline void rvt_put_mr(struct rvt_mregion *mr)
125 {
126 	if (unlikely(atomic_dec_and_test(&mr->refcount)))
127 		complete(&mr->comp);
128 }
129 
130 static inline void rvt_get_mr(struct rvt_mregion *mr)
131 {
132 	atomic_inc(&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 #endif          /* DEF_RDMAVT_INCMRH */
145