xref: /openbmc/linux/net/sunrpc/xprtrdma/svc_rdma.c (revision 4f3db074)
1 /*
2  * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the BSD-type
8  * license below:
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  *
14  *      Redistributions of source code must retain the above copyright
15  *      notice, this list of conditions and the following disclaimer.
16  *
17  *      Redistributions in binary form must reproduce the above
18  *      copyright notice, this list of conditions and the following
19  *      disclaimer in the documentation and/or other materials provided
20  *      with the distribution.
21  *
22  *      Neither the name of the Network Appliance, Inc. nor the names of
23  *      its contributors may be used to endorse or promote products
24  *      derived from this software without specific prior written
25  *      permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38  *
39  * Author: Tom Tucker <tom@opengridcomputing.com>
40  */
41 #include <linux/module.h>
42 #include <linux/init.h>
43 #include <linux/slab.h>
44 #include <linux/fs.h>
45 #include <linux/sysctl.h>
46 #include <linux/workqueue.h>
47 #include <linux/sunrpc/clnt.h>
48 #include <linux/sunrpc/sched.h>
49 #include <linux/sunrpc/svc_rdma.h>
50 #include "xprt_rdma.h"
51 
52 #define RPCDBG_FACILITY	RPCDBG_SVCXPRT
53 
54 /* RPC/RDMA parameters */
55 unsigned int svcrdma_ord = RPCRDMA_ORD;
56 static unsigned int min_ord = 1;
57 static unsigned int max_ord = 4096;
58 unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
59 static unsigned int min_max_requests = 4;
60 static unsigned int max_max_requests = 16384;
61 unsigned int svcrdma_max_req_size = RPCRDMA_MAX_REQ_SIZE;
62 static unsigned int min_max_inline = 4096;
63 static unsigned int max_max_inline = 65536;
64 
65 atomic_t rdma_stat_recv;
66 atomic_t rdma_stat_read;
67 atomic_t rdma_stat_write;
68 atomic_t rdma_stat_sq_starve;
69 atomic_t rdma_stat_rq_starve;
70 atomic_t rdma_stat_rq_poll;
71 atomic_t rdma_stat_rq_prod;
72 atomic_t rdma_stat_sq_poll;
73 atomic_t rdma_stat_sq_prod;
74 
75 /* Temporary NFS request map and context caches */
76 struct kmem_cache *svc_rdma_map_cachep;
77 struct kmem_cache *svc_rdma_ctxt_cachep;
78 
79 struct workqueue_struct *svc_rdma_wq;
80 
81 /*
82  * This function implements reading and resetting an atomic_t stat
83  * variable through read/write to a proc file. Any write to the file
84  * resets the associated statistic to zero. Any read returns it's
85  * current value.
86  */
87 static int read_reset_stat(struct ctl_table *table, int write,
88 			   void __user *buffer, size_t *lenp,
89 			   loff_t *ppos)
90 {
91 	atomic_t *stat = (atomic_t *)table->data;
92 
93 	if (!stat)
94 		return -EINVAL;
95 
96 	if (write)
97 		atomic_set(stat, 0);
98 	else {
99 		char str_buf[32];
100 		char *data;
101 		int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
102 		if (len >= 32)
103 			return -EFAULT;
104 		len = strlen(str_buf);
105 		if (*ppos > len) {
106 			*lenp = 0;
107 			return 0;
108 		}
109 		data = &str_buf[*ppos];
110 		len -= *ppos;
111 		if (len > *lenp)
112 			len = *lenp;
113 		if (len && copy_to_user(buffer, str_buf, len))
114 			return -EFAULT;
115 		*lenp = len;
116 		*ppos += len;
117 	}
118 	return 0;
119 }
120 
121 static struct ctl_table_header *svcrdma_table_header;
122 static struct ctl_table svcrdma_parm_table[] = {
123 	{
124 		.procname	= "max_requests",
125 		.data		= &svcrdma_max_requests,
126 		.maxlen		= sizeof(unsigned int),
127 		.mode		= 0644,
128 		.proc_handler	= proc_dointvec_minmax,
129 		.extra1		= &min_max_requests,
130 		.extra2		= &max_max_requests
131 	},
132 	{
133 		.procname	= "max_req_size",
134 		.data		= &svcrdma_max_req_size,
135 		.maxlen		= sizeof(unsigned int),
136 		.mode		= 0644,
137 		.proc_handler	= proc_dointvec_minmax,
138 		.extra1		= &min_max_inline,
139 		.extra2		= &max_max_inline
140 	},
141 	{
142 		.procname	= "max_outbound_read_requests",
143 		.data		= &svcrdma_ord,
144 		.maxlen		= sizeof(unsigned int),
145 		.mode		= 0644,
146 		.proc_handler	= proc_dointvec_minmax,
147 		.extra1		= &min_ord,
148 		.extra2		= &max_ord,
149 	},
150 
151 	{
152 		.procname	= "rdma_stat_read",
153 		.data		= &rdma_stat_read,
154 		.maxlen		= sizeof(atomic_t),
155 		.mode		= 0644,
156 		.proc_handler	= read_reset_stat,
157 	},
158 	{
159 		.procname	= "rdma_stat_recv",
160 		.data		= &rdma_stat_recv,
161 		.maxlen		= sizeof(atomic_t),
162 		.mode		= 0644,
163 		.proc_handler	= read_reset_stat,
164 	},
165 	{
166 		.procname	= "rdma_stat_write",
167 		.data		= &rdma_stat_write,
168 		.maxlen		= sizeof(atomic_t),
169 		.mode		= 0644,
170 		.proc_handler	= read_reset_stat,
171 	},
172 	{
173 		.procname	= "rdma_stat_sq_starve",
174 		.data		= &rdma_stat_sq_starve,
175 		.maxlen		= sizeof(atomic_t),
176 		.mode		= 0644,
177 		.proc_handler	= read_reset_stat,
178 	},
179 	{
180 		.procname	= "rdma_stat_rq_starve",
181 		.data		= &rdma_stat_rq_starve,
182 		.maxlen		= sizeof(atomic_t),
183 		.mode		= 0644,
184 		.proc_handler	= read_reset_stat,
185 	},
186 	{
187 		.procname	= "rdma_stat_rq_poll",
188 		.data		= &rdma_stat_rq_poll,
189 		.maxlen		= sizeof(atomic_t),
190 		.mode		= 0644,
191 		.proc_handler	= read_reset_stat,
192 	},
193 	{
194 		.procname	= "rdma_stat_rq_prod",
195 		.data		= &rdma_stat_rq_prod,
196 		.maxlen		= sizeof(atomic_t),
197 		.mode		= 0644,
198 		.proc_handler	= read_reset_stat,
199 	},
200 	{
201 		.procname	= "rdma_stat_sq_poll",
202 		.data		= &rdma_stat_sq_poll,
203 		.maxlen		= sizeof(atomic_t),
204 		.mode		= 0644,
205 		.proc_handler	= read_reset_stat,
206 	},
207 	{
208 		.procname	= "rdma_stat_sq_prod",
209 		.data		= &rdma_stat_sq_prod,
210 		.maxlen		= sizeof(atomic_t),
211 		.mode		= 0644,
212 		.proc_handler	= read_reset_stat,
213 	},
214 	{ },
215 };
216 
217 static struct ctl_table svcrdma_table[] = {
218 	{
219 		.procname	= "svc_rdma",
220 		.mode		= 0555,
221 		.child		= svcrdma_parm_table
222 	},
223 	{ },
224 };
225 
226 static struct ctl_table svcrdma_root_table[] = {
227 	{
228 		.procname	= "sunrpc",
229 		.mode		= 0555,
230 		.child		= svcrdma_table
231 	},
232 	{ },
233 };
234 
235 void svc_rdma_cleanup(void)
236 {
237 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
238 	destroy_workqueue(svc_rdma_wq);
239 	if (svcrdma_table_header) {
240 		unregister_sysctl_table(svcrdma_table_header);
241 		svcrdma_table_header = NULL;
242 	}
243 	svc_unreg_xprt_class(&svc_rdma_class);
244 	kmem_cache_destroy(svc_rdma_map_cachep);
245 	kmem_cache_destroy(svc_rdma_ctxt_cachep);
246 }
247 
248 int svc_rdma_init(void)
249 {
250 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
251 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
252 	dprintk("\tmax_requests     : %d\n", svcrdma_max_requests);
253 	dprintk("\tsq_depth         : %d\n",
254 		svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT);
255 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
256 
257 	svc_rdma_wq = alloc_workqueue("svc_rdma", 0, 0);
258 	if (!svc_rdma_wq)
259 		return -ENOMEM;
260 
261 	if (!svcrdma_table_header)
262 		svcrdma_table_header =
263 			register_sysctl_table(svcrdma_root_table);
264 
265 	/* Create the temporary map cache */
266 	svc_rdma_map_cachep = kmem_cache_create("svc_rdma_map_cache",
267 						sizeof(struct svc_rdma_req_map),
268 						0,
269 						SLAB_HWCACHE_ALIGN,
270 						NULL);
271 	if (!svc_rdma_map_cachep) {
272 		printk(KERN_INFO "Could not allocate map cache.\n");
273 		goto err0;
274 	}
275 
276 	/* Create the temporary context cache */
277 	svc_rdma_ctxt_cachep =
278 		kmem_cache_create("svc_rdma_ctxt_cache",
279 				  sizeof(struct svc_rdma_op_ctxt),
280 				  0,
281 				  SLAB_HWCACHE_ALIGN,
282 				  NULL);
283 	if (!svc_rdma_ctxt_cachep) {
284 		printk(KERN_INFO "Could not allocate WR ctxt cache.\n");
285 		goto err1;
286 	}
287 
288 	/* Register RDMA with the SVC transport switch */
289 	svc_reg_xprt_class(&svc_rdma_class);
290 	return 0;
291  err1:
292 	kmem_cache_destroy(svc_rdma_map_cachep);
293  err0:
294 	unregister_sysctl_table(svcrdma_table_header);
295 	destroy_workqueue(svc_rdma_wq);
296 	return -ENOMEM;
297 }
298 MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>");
299 MODULE_DESCRIPTION("SVC RDMA Transport");
300 MODULE_LICENSE("Dual BSD/GPL");
301 module_init(svc_rdma_init);
302 module_exit(svc_rdma_cleanup);
303