1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
3  *
4  * Copyright (c) 2004, 2005 Mellanox Technologies Ltd.  All rights reserved.
5  * Copyright (c) 2004, 2005 Infinicon Corporation.  All rights reserved.
6  * Copyright (c) 2004, 2005 Intel Corporation.  All rights reserved.
7  * Copyright (c) 2004, 2005 Topspin Corporation.  All rights reserved.
8  * Copyright (c) 2004-2007 Voltaire Corporation.  All rights reserved.
9  * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
10  *
11  * This software is available to you under a choice of one of two
12  * licenses.  You may choose to be licensed under the terms of the GNU
13  * General Public License (GPL) Version 2, available from the file
14  * COPYING in the main directory of this source tree, or the
15  * OpenIB.org BSD license below:
16  *
17  *     Redistribution and use in source and binary forms, with or
18  *     without modification, are permitted provided that the following
19  *     conditions are met:
20  *
21  *      - Redistributions of source code must retain the above
22  *        copyright notice, this list of conditions and the following
23  *        disclaimer.
24  *
25  *      - Redistributions in binary form must reproduce the above
26  *        copyright notice, this list of conditions and the following
27  *        disclaimer in the documentation and/or other materials
28  *        provided with the distribution.
29  *
30  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
31  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
32  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
33  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
34  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
35  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
36  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
37  * SOFTWARE.
38  */
39 
40 #include <sys/cdefs.h>
41 #include <linux/slab.h>
42 #include <linux/string.h>
43 
44 #include "agent.h"
45 #include "smi.h"
46 #include "mad_priv.h"
47 
48 #define SPFX "ib_agent: "
49 
50 struct ib_agent_port_private {
51 	struct list_head port_list;
52 	struct ib_mad_agent *agent[2];
53 };
54 
55 static DEFINE_SPINLOCK(ib_agent_port_list_lock);
56 static LIST_HEAD(ib_agent_port_list);
57 
58 static struct ib_agent_port_private *
59 __ib_get_agent_port(const struct ib_device *device, int port_num)
60 {
61 	struct ib_agent_port_private *entry;
62 
63 	list_for_each_entry(entry, &ib_agent_port_list, port_list) {
64 		if (entry->agent[1]->device == device &&
65 		    entry->agent[1]->port_num == port_num)
66 			return entry;
67 	}
68 	return NULL;
69 }
70 
71 static struct ib_agent_port_private *
72 ib_get_agent_port(const struct ib_device *device, int port_num)
73 {
74 	struct ib_agent_port_private *entry;
75 	unsigned long flags;
76 
77 	spin_lock_irqsave(&ib_agent_port_list_lock, flags);
78 	entry = __ib_get_agent_port(device, port_num);
79 	spin_unlock_irqrestore(&ib_agent_port_list_lock, flags);
80 	return entry;
81 }
82 
83 void agent_send_response(const struct ib_mad_hdr *mad_hdr, const struct ib_grh *grh,
84 			 const struct ib_wc *wc, const struct ib_device *device,
85 			 int port_num, int qpn, size_t resp_mad_len, bool opa)
86 {
87 	struct ib_agent_port_private *port_priv;
88 	struct ib_mad_agent *agent;
89 	struct ib_mad_send_buf *send_buf;
90 	struct ib_ah *ah;
91 	struct ib_mad_send_wr_private *mad_send_wr;
92 
93 	if (rdma_cap_ib_switch(device))
94 		port_priv = ib_get_agent_port(device, 0);
95 	else
96 		port_priv = ib_get_agent_port(device, port_num);
97 
98 	if (!port_priv) {
99 		dev_err(&device->dev, "Unable to find port agent\n");
100 		return;
101 	}
102 
103 	agent = port_priv->agent[qpn];
104 	ah = ib_create_ah_from_wc(agent->qp->pd, wc, grh, port_num);
105 	if (IS_ERR(ah)) {
106 		dev_err(&device->dev, "ib_create_ah_from_wc error %ld\n",
107 			PTR_ERR(ah));
108 		return;
109 	}
110 
111 	if (opa && mad_hdr->base_version != OPA_MGMT_BASE_VERSION)
112 		resp_mad_len = IB_MGMT_MAD_SIZE;
113 
114 	send_buf = ib_create_send_mad(agent, wc->src_qp, wc->pkey_index, 0,
115 				      IB_MGMT_MAD_HDR,
116 				      resp_mad_len - IB_MGMT_MAD_HDR,
117 				      GFP_KERNEL,
118 				      mad_hdr->base_version);
119 	if (IS_ERR(send_buf)) {
120 		dev_err(&device->dev, "ib_create_send_mad error\n");
121 		goto err1;
122 	}
123 
124 	memcpy(send_buf->mad, mad_hdr, resp_mad_len);
125 	send_buf->ah = ah;
126 
127 	if (rdma_cap_ib_switch(device)) {
128 		mad_send_wr = container_of(send_buf,
129 					   struct ib_mad_send_wr_private,
130 					   send_buf);
131 		mad_send_wr->send_wr.port_num = port_num;
132 	}
133 
134 	if (ib_post_send_mad(send_buf, NULL)) {
135 		dev_err(&device->dev, "ib_post_send_mad error\n");
136 		goto err2;
137 	}
138 	return;
139 err2:
140 	ib_free_send_mad(send_buf);
141 err1:
142 	ib_destroy_ah(ah, RDMA_DESTROY_AH_SLEEPABLE);
143 }
144 
145 static void agent_send_handler(struct ib_mad_agent *mad_agent,
146 			       struct ib_mad_send_wc *mad_send_wc)
147 {
148 	ib_destroy_ah(mad_send_wc->send_buf->ah, RDMA_DESTROY_AH_SLEEPABLE);
149 	ib_free_send_mad(mad_send_wc->send_buf);
150 }
151 
152 int ib_agent_port_open(struct ib_device *device, int port_num)
153 {
154 	struct ib_agent_port_private *port_priv;
155 	unsigned long flags;
156 	int ret;
157 
158 	/* Create new device info */
159 	port_priv = kzalloc(sizeof *port_priv, GFP_KERNEL);
160 	if (!port_priv) {
161 		dev_err(&device->dev, "No memory for ib_agent_port_private\n");
162 		ret = -ENOMEM;
163 		goto error1;
164 	}
165 
166 	if (rdma_cap_ib_smi(device, port_num)) {
167 		/* Obtain send only MAD agent for SMI QP */
168 		port_priv->agent[0] = ib_register_mad_agent(device, port_num,
169 							    IB_QPT_SMI, NULL, 0,
170 							    &agent_send_handler,
171 							    NULL, NULL, 0);
172 		if (IS_ERR(port_priv->agent[0])) {
173 			ret = PTR_ERR(port_priv->agent[0]);
174 			goto error2;
175 		}
176 	}
177 
178 	/* Obtain send only MAD agent for GSI QP */
179 	port_priv->agent[1] = ib_register_mad_agent(device, port_num,
180 						    IB_QPT_GSI, NULL, 0,
181 						    &agent_send_handler,
182 						    NULL, NULL, 0);
183 	if (IS_ERR(port_priv->agent[1])) {
184 		ret = PTR_ERR(port_priv->agent[1]);
185 		goto error3;
186 	}
187 
188 	spin_lock_irqsave(&ib_agent_port_list_lock, flags);
189 	list_add_tail(&port_priv->port_list, &ib_agent_port_list);
190 	spin_unlock_irqrestore(&ib_agent_port_list_lock, flags);
191 
192 	return 0;
193 
194 error3:
195 	if (port_priv->agent[0])
196 		ib_unregister_mad_agent(port_priv->agent[0]);
197 error2:
198 	kfree(port_priv);
199 error1:
200 	return ret;
201 }
202 
203 int ib_agent_port_close(struct ib_device *device, int port_num)
204 {
205 	struct ib_agent_port_private *port_priv;
206 	unsigned long flags;
207 
208 	spin_lock_irqsave(&ib_agent_port_list_lock, flags);
209 	port_priv = __ib_get_agent_port(device, port_num);
210 	if (port_priv == NULL) {
211 		spin_unlock_irqrestore(&ib_agent_port_list_lock, flags);
212 		dev_err(&device->dev, "Port %d not found\n", port_num);
213 		return -ENODEV;
214 	}
215 	list_del(&port_priv->port_list);
216 	spin_unlock_irqrestore(&ib_agent_port_list_lock, flags);
217 
218 	ib_unregister_mad_agent(port_priv->agent[1]);
219 	if (port_priv->agent[0])
220 		ib_unregister_mad_agent(port_priv->agent[0]);
221 
222 	kfree(port_priv);
223 	return 0;
224 }
225