kernel/net/sunrpc/xprtrdma/svc_rdma.c

   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);