xref: /openbmc/linux/net/sunrpc/xprtrdma/svc_rdma.c (revision a09d2831)
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/fs.h>
44 #include <linux/sysctl.h>
45 #include <linux/sunrpc/clnt.h>
46 #include <linux/sunrpc/sched.h>
47 #include <linux/sunrpc/svc_rdma.h>
48 
49 #define RPCDBG_FACILITY	RPCDBG_SVCXPRT
50 
51 /* RPC/RDMA parameters */
52 unsigned int svcrdma_ord = RPCRDMA_ORD;
53 static unsigned int min_ord = 1;
54 static unsigned int max_ord = 4096;
55 unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
56 static unsigned int min_max_requests = 4;
57 static unsigned int max_max_requests = 16384;
58 unsigned int svcrdma_max_req_size = RPCRDMA_MAX_REQ_SIZE;
59 static unsigned int min_max_inline = 4096;
60 static unsigned int max_max_inline = 65536;
61 
62 atomic_t rdma_stat_recv;
63 atomic_t rdma_stat_read;
64 atomic_t rdma_stat_write;
65 atomic_t rdma_stat_sq_starve;
66 atomic_t rdma_stat_rq_starve;
67 atomic_t rdma_stat_rq_poll;
68 atomic_t rdma_stat_rq_prod;
69 atomic_t rdma_stat_sq_poll;
70 atomic_t rdma_stat_sq_prod;
71 
72 /* Temporary NFS request map and context caches */
73 struct kmem_cache *svc_rdma_map_cachep;
74 struct kmem_cache *svc_rdma_ctxt_cachep;
75 
76 /*
77  * This function implements reading and resetting an atomic_t stat
78  * variable through read/write to a proc file. Any write to the file
79  * resets the associated statistic to zero. Any read returns it's
80  * current value.
81  */
82 static int read_reset_stat(ctl_table *table, int write,
83 			   void __user *buffer, size_t *lenp,
84 			   loff_t *ppos)
85 {
86 	atomic_t *stat = (atomic_t *)table->data;
87 
88 	if (!stat)
89 		return -EINVAL;
90 
91 	if (write)
92 		atomic_set(stat, 0);
93 	else {
94 		char str_buf[32];
95 		char *data;
96 		int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
97 		if (len >= 32)
98 			return -EFAULT;
99 		len = strlen(str_buf);
100 		if (*ppos > len) {
101 			*lenp = 0;
102 			return 0;
103 		}
104 		data = &str_buf[*ppos];
105 		len -= *ppos;
106 		if (len > *lenp)
107 			len = *lenp;
108 		if (len && copy_to_user(buffer, str_buf, len))
109 			return -EFAULT;
110 		*lenp = len;
111 		*ppos += len;
112 	}
113 	return 0;
114 }
115 
116 static struct ctl_table_header *svcrdma_table_header;
117 static ctl_table svcrdma_parm_table[] = {
118 	{
119 		.procname	= "max_requests",
120 		.data		= &svcrdma_max_requests,
121 		.maxlen		= sizeof(unsigned int),
122 		.mode		= 0644,
123 		.proc_handler	= proc_dointvec_minmax,
124 		.extra1		= &min_max_requests,
125 		.extra2		= &max_max_requests
126 	},
127 	{
128 		.procname	= "max_req_size",
129 		.data		= &svcrdma_max_req_size,
130 		.maxlen		= sizeof(unsigned int),
131 		.mode		= 0644,
132 		.proc_handler	= proc_dointvec_minmax,
133 		.extra1		= &min_max_inline,
134 		.extra2		= &max_max_inline
135 	},
136 	{
137 		.procname	= "max_outbound_read_requests",
138 		.data		= &svcrdma_ord,
139 		.maxlen		= sizeof(unsigned int),
140 		.mode		= 0644,
141 		.proc_handler	= proc_dointvec_minmax,
142 		.extra1		= &min_ord,
143 		.extra2		= &max_ord,
144 	},
145 
146 	{
147 		.procname	= "rdma_stat_read",
148 		.data		= &rdma_stat_read,
149 		.maxlen		= sizeof(atomic_t),
150 		.mode		= 0644,
151 		.proc_handler	= read_reset_stat,
152 	},
153 	{
154 		.procname	= "rdma_stat_recv",
155 		.data		= &rdma_stat_recv,
156 		.maxlen		= sizeof(atomic_t),
157 		.mode		= 0644,
158 		.proc_handler	= read_reset_stat,
159 	},
160 	{
161 		.procname	= "rdma_stat_write",
162 		.data		= &rdma_stat_write,
163 		.maxlen		= sizeof(atomic_t),
164 		.mode		= 0644,
165 		.proc_handler	= read_reset_stat,
166 	},
167 	{
168 		.procname	= "rdma_stat_sq_starve",
169 		.data		= &rdma_stat_sq_starve,
170 		.maxlen		= sizeof(atomic_t),
171 		.mode		= 0644,
172 		.proc_handler	= read_reset_stat,
173 	},
174 	{
175 		.procname	= "rdma_stat_rq_starve",
176 		.data		= &rdma_stat_rq_starve,
177 		.maxlen		= sizeof(atomic_t),
178 		.mode		= 0644,
179 		.proc_handler	= read_reset_stat,
180 	},
181 	{
182 		.procname	= "rdma_stat_rq_poll",
183 		.data		= &rdma_stat_rq_poll,
184 		.maxlen		= sizeof(atomic_t),
185 		.mode		= 0644,
186 		.proc_handler	= read_reset_stat,
187 	},
188 	{
189 		.procname	= "rdma_stat_rq_prod",
190 		.data		= &rdma_stat_rq_prod,
191 		.maxlen		= sizeof(atomic_t),
192 		.mode		= 0644,
193 		.proc_handler	= read_reset_stat,
194 	},
195 	{
196 		.procname	= "rdma_stat_sq_poll",
197 		.data		= &rdma_stat_sq_poll,
198 		.maxlen		= sizeof(atomic_t),
199 		.mode		= 0644,
200 		.proc_handler	= read_reset_stat,
201 	},
202 	{
203 		.procname	= "rdma_stat_sq_prod",
204 		.data		= &rdma_stat_sq_prod,
205 		.maxlen		= sizeof(atomic_t),
206 		.mode		= 0644,
207 		.proc_handler	= read_reset_stat,
208 	},
209 	{ },
210 };
211 
212 static ctl_table svcrdma_table[] = {
213 	{
214 		.procname	= "svc_rdma",
215 		.mode		= 0555,
216 		.child		= svcrdma_parm_table
217 	},
218 	{ },
219 };
220 
221 static ctl_table svcrdma_root_table[] = {
222 	{
223 		.procname	= "sunrpc",
224 		.mode		= 0555,
225 		.child		= svcrdma_table
226 	},
227 	{ },
228 };
229 
230 void svc_rdma_cleanup(void)
231 {
232 	dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
233 	flush_scheduled_work();
234 	if (svcrdma_table_header) {
235 		unregister_sysctl_table(svcrdma_table_header);
236 		svcrdma_table_header = NULL;
237 	}
238 	svc_unreg_xprt_class(&svc_rdma_class);
239 	kmem_cache_destroy(svc_rdma_map_cachep);
240 	kmem_cache_destroy(svc_rdma_ctxt_cachep);
241 }
242 
243 int svc_rdma_init(void)
244 {
245 	dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
246 	dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
247 	dprintk("\tmax_requests     : %d\n", svcrdma_max_requests);
248 	dprintk("\tsq_depth         : %d\n",
249 		svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT);
250 	dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
251 	if (!svcrdma_table_header)
252 		svcrdma_table_header =
253 			register_sysctl_table(svcrdma_root_table);
254 
255 	/* Create the temporary map cache */
256 	svc_rdma_map_cachep = kmem_cache_create("svc_rdma_map_cache",
257 						sizeof(struct svc_rdma_req_map),
258 						0,
259 						SLAB_HWCACHE_ALIGN,
260 						NULL);
261 	if (!svc_rdma_map_cachep) {
262 		printk(KERN_INFO "Could not allocate map cache.\n");
263 		goto err0;
264 	}
265 
266 	/* Create the temporary context cache */
267 	svc_rdma_ctxt_cachep =
268 		kmem_cache_create("svc_rdma_ctxt_cache",
269 				  sizeof(struct svc_rdma_op_ctxt),
270 				  0,
271 				  SLAB_HWCACHE_ALIGN,
272 				  NULL);
273 	if (!svc_rdma_ctxt_cachep) {
274 		printk(KERN_INFO "Could not allocate WR ctxt cache.\n");
275 		goto err1;
276 	}
277 
278 	/* Register RDMA with the SVC transport switch */
279 	svc_reg_xprt_class(&svc_rdma_class);
280 	return 0;
281  err1:
282 	kmem_cache_destroy(svc_rdma_map_cachep);
283  err0:
284 	unregister_sysctl_table(svcrdma_table_header);
285 	return -ENOMEM;
286 }
287 MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>");
288 MODULE_DESCRIPTION("SVC RDMA Transport");
289 MODULE_LICENSE("Dual BSD/GPL");
290 module_init(svc_rdma_init);
291 module_exit(svc_rdma_cleanup);
292