xref: /openbmc/linux/drivers/infiniband/sw/rdmavt/pd.c (revision 9a8f3203)
1 /*
2  * Copyright(c) 2016 Intel Corporation.
3  *
4  * This file is provided under a dual BSD/GPLv2 license.  When using or
5  * redistributing this file, you may do so under either license.
6  *
7  * GPL LICENSE SUMMARY
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * BSD LICENSE
19  *
20  * Redistribution and use in source and binary forms, with or without
21  * modification, are permitted provided that the following conditions
22  * are met:
23  *
24  *  - Redistributions of source code must retain the above copyright
25  *    notice, this list of conditions and the following disclaimer.
26  *  - Redistributions in binary form must reproduce the above copyright
27  *    notice, this list of conditions and the following disclaimer in
28  *    the documentation and/or other materials provided with the
29  *    distribution.
30  *  - Neither the name of Intel Corporation nor the names of its
31  *    contributors may be used to endorse or promote products derived
32  *    from this software without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45  *
46  */
47 
48 #include <linux/slab.h>
49 #include "pd.h"
50 
51 /**
52  * rvt_alloc_pd - allocate a protection domain
53  * @ibpd: PD
54  * @context: optional user context
55  * @udata: optional user data
56  *
57  * Allocate and keep track of a PD.
58  *
59  * Return: 0 on success
60  */
61 int rvt_alloc_pd(struct ib_pd *ibpd, struct ib_ucontext *context,
62 		 struct ib_udata *udata)
63 {
64 	struct ib_device *ibdev = ibpd->device;
65 	struct rvt_dev_info *dev = ib_to_rvt(ibdev);
66 	struct rvt_pd *pd = ibpd_to_rvtpd(ibpd);
67 	int ret = 0;
68 
69 	/*
70 	 * While we could continue allocating protecetion domains, being
71 	 * constrained only by system resources. The IBTA spec defines that
72 	 * there is a max_pd limit that can be set and we need to check for
73 	 * that.
74 	 */
75 
76 	spin_lock(&dev->n_pds_lock);
77 	if (dev->n_pds_allocated == dev->dparms.props.max_pd) {
78 		spin_unlock(&dev->n_pds_lock);
79 		ret = -ENOMEM;
80 		goto bail;
81 	}
82 
83 	dev->n_pds_allocated++;
84 	spin_unlock(&dev->n_pds_lock);
85 
86 	/* ib_alloc_pd() will initialize pd->ibpd. */
87 	pd->user = !!udata;
88 
89 bail:
90 	return ret;
91 }
92 
93 /**
94  * rvt_dealloc_pd - Free PD
95  * @ibpd: Free up PD
96  *
97  * Return: always 0
98  */
99 void rvt_dealloc_pd(struct ib_pd *ibpd)
100 {
101 	struct rvt_dev_info *dev = ib_to_rvt(ibpd->device);
102 
103 	spin_lock(&dev->n_pds_lock);
104 	dev->n_pds_allocated--;
105 	spin_unlock(&dev->n_pds_lock);
106 }
107