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
  51 #define RPCDBG_FACILITY RPCDBG_SVCXPRT
  52
  53 /* RPC/RDMA parameters */
  54 unsigned int svcrdma_ord = RPCRDMA_ORD;
  55 static unsigned int min_ord = 1;
  56 static unsigned int max_ord = 4096;
  57 unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
  58 static unsigned int min_max_requests = 4;
  59 static unsigned int max_max_requests = 16384;
  60 unsigned int svcrdma_max_req_size = RPCRDMA_MAX_REQ_SIZE;
  61 static unsigned int min_max_inline = 4096;
  62 static unsigned int max_max_inline = 65536;
  63
  64 atomic_t rdma_stat_recv;
  65 atomic_t rdma_stat_read;
  66 atomic_t rdma_stat_write;
  67 atomic_t rdma_stat_sq_starve;
  68 atomic_t rdma_stat_rq_starve;
  69 atomic_t rdma_stat_rq_poll;
  70 atomic_t rdma_stat_rq_prod;
  71 atomic_t rdma_stat_sq_poll;
  72 atomic_t rdma_stat_sq_prod;
  73
  74 /* Temporary NFS request map and context caches */
  75 struct kmem_cache *svc_rdma_map_cachep;
  76 struct kmem_cache *svc_rdma_ctxt_cachep;
  77
  78 struct workqueue_struct *svc_rdma_wq;
  79
  80 /*
  81  * This function implements reading and resetting an atomic_t stat
  82  * variable through read/write to a proc file. Any write to the file
  83  * resets the associated statistic to zero. Any read returns it's
  84  * current value.
  85  */
  86 static int read_reset_stat(ctl_table *table, int write,
  87                            void __user *buffer, size_t *lenp,
  88                            loff_t *ppos)
  89 {
  90         atomic_t *stat = (atomic_t *)table->data;
  91
  92         if (!stat)
  93                 return -EINVAL;
  94
  95         if (write)
  96                 atomic_set(stat, 0);
  97         else {
  98                 char str_buf[32];
  99                 char *data;
 100                 int len = snprintf(str_buf, 32, "%d\n", atomic_read(stat));
 101                 if (len >= 32)
 102                         return -EFAULT;
 103                 len = strlen(str_buf);
 104                 if (*ppos > len) {
 105                         *lenp = 0;
 106                         return 0;
 107                 }
 108                 data = &str_buf[*ppos];
 109                 len -= *ppos;
 110                 if (len > *lenp)
 111                         len = *lenp;
 112                 if (len && copy_to_user(buffer, str_buf, len))
 113                         return -EFAULT;
 114                 *lenp = len;
 115                 *ppos += len;
 116         }
 117         return 0;
 118 }
 119
 120 static struct ctl_table_header *svcrdma_table_header;
 121 static ctl_table svcrdma_parm_table[] = {
 122         {
 123                 .procname       = "max_requests",
 124                 .data           = &svcrdma_max_requests,
 125                 .maxlen         = sizeof(unsigned int),
 126                 .mode           = 0644,
 127                 .proc_handler   = proc_dointvec_minmax,
 128                 .extra1         = &min_max_requests,
 129                 .extra2         = &max_max_requests
 130         },
 131         {
 132                 .procname       = "max_req_size",
 133                 .data           = &svcrdma_max_req_size,
 134                 .maxlen         = sizeof(unsigned int),
 135                 .mode           = 0644,
 136                 .proc_handler   = proc_dointvec_minmax,
 137                 .extra1         = &min_max_inline,
 138                 .extra2         = &max_max_inline
 139         },
 140         {
 141                 .procname       = "max_outbound_read_requests",
 142                 .data           = &svcrdma_ord,
 143                 .maxlen         = sizeof(unsigned int),
 144                 .mode           = 0644,
 145                 .proc_handler   = proc_dointvec_minmax,
 146                 .extra1         = &min_ord,
 147                 .extra2         = &max_ord,
 148         },
 149
 150         {
 151                 .procname       = "rdma_stat_read",
 152                 .data           = &rdma_stat_read,
 153                 .maxlen         = sizeof(atomic_t),
 154                 .mode           = 0644,
 155                 .proc_handler   = read_reset_stat,
 156         },
 157         {
 158                 .procname       = "rdma_stat_recv",
 159                 .data           = &rdma_stat_recv,
 160                 .maxlen         = sizeof(atomic_t),
 161                 .mode           = 0644,
 162                 .proc_handler   = read_reset_stat,
 163         },
 164         {
 165                 .procname       = "rdma_stat_write",
 166                 .data           = &rdma_stat_write,
 167                 .maxlen         = sizeof(atomic_t),
 168                 .mode           = 0644,
 169                 .proc_handler   = read_reset_stat,
 170         },
 171         {
 172                 .procname       = "rdma_stat_sq_starve",
 173                 .data           = &rdma_stat_sq_starve,
 174                 .maxlen         = sizeof(atomic_t),
 175                 .mode           = 0644,
 176                 .proc_handler   = read_reset_stat,
 177         },
 178         {
 179                 .procname       = "rdma_stat_rq_starve",
 180                 .data           = &rdma_stat_rq_starve,
 181                 .maxlen         = sizeof(atomic_t),
 182                 .mode           = 0644,
 183                 .proc_handler   = read_reset_stat,
 184         },
 185         {
 186                 .procname       = "rdma_stat_rq_poll",
 187                 .data           = &rdma_stat_rq_poll,
 188                 .maxlen         = sizeof(atomic_t),
 189                 .mode           = 0644,
 190                 .proc_handler   = read_reset_stat,
 191         },
 192         {
 193                 .procname       = "rdma_stat_rq_prod",
 194                 .data           = &rdma_stat_rq_prod,
 195                 .maxlen         = sizeof(atomic_t),
 196                 .mode           = 0644,
 197                 .proc_handler   = read_reset_stat,
 198         },
 199         {
 200                 .procname       = "rdma_stat_sq_poll",
 201                 .data           = &rdma_stat_sq_poll,
 202                 .maxlen         = sizeof(atomic_t),
 203                 .mode           = 0644,
 204                 .proc_handler   = read_reset_stat,
 205         },
 206         {
 207                 .procname       = "rdma_stat_sq_prod",
 208                 .data           = &rdma_stat_sq_prod,
 209                 .maxlen         = sizeof(atomic_t),
 210                 .mode           = 0644,
 211                 .proc_handler   = read_reset_stat,
 212         },
 213         { },
 214 };
 215
 216 static ctl_table svcrdma_table[] = {
 217         {
 218                 .procname       = "svc_rdma",
 219                 .mode           = 0555,
 220                 .child          = svcrdma_parm_table
 221         },
 222         { },
 223 };
 224
 225 static ctl_table svcrdma_root_table[] = {
 226         {
 227                 .procname       = "sunrpc",
 228                 .mode           = 0555,
 229                 .child          = svcrdma_table
 230         },
 231         { },
 232 };
 233
 234 void svc_rdma_cleanup(void)
 235 {
 236         dprintk("SVCRDMA Module Removed, deregister RPC RDMA transport\n");
 237         destroy_workqueue(svc_rdma_wq);
 238         if (svcrdma_table_header) {
 239                 unregister_sysctl_table(svcrdma_table_header);
 240                 svcrdma_table_header = NULL;
 241         }
 242         svc_unreg_xprt_class(&svc_rdma_class);
 243         kmem_cache_destroy(svc_rdma_map_cachep);
 244         kmem_cache_destroy(svc_rdma_ctxt_cachep);
 245 }
 246
 247 int svc_rdma_init(void)
 248 {
 249         dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
 250         dprintk("\tsvcrdma_ord      : %d\n", svcrdma_ord);
 251         dprintk("\tmax_requests     : %d\n", svcrdma_max_requests);
 252         dprintk("\tsq_depth         : %d\n",
 253                 svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT);
 254         dprintk("\tmax_inline       : %d\n", svcrdma_max_req_size);
 255
 256         svc_rdma_wq = alloc_workqueue("svc_rdma", 0, 0);
 257         if (!svc_rdma_wq)
 258                 return -ENOMEM;
 259
 260         if (!svcrdma_table_header)
 261                 svcrdma_table_header =
 262                         register_sysctl_table(svcrdma_root_table);
 263
 264         /* Create the temporary map cache */
 265         svc_rdma_map_cachep = kmem_cache_create("svc_rdma_map_cache",
 266                                                 sizeof(struct svc_rdma_req_map),
 267                                                 0,
 268                                                 SLAB_HWCACHE_ALIGN,
 269                                                 NULL);
 270         if (!svc_rdma_map_cachep) {
 271                 printk(KERN_INFO "Could not allocate map cache.\n");
 272                 goto err0;
 273         }
 274
 275         /* Create the temporary context cache */
 276         svc_rdma_ctxt_cachep =
 277                 kmem_cache_create("svc_rdma_ctxt_cache",
 278                                   sizeof(struct svc_rdma_op_ctxt),
 279                                   0,
 280                                   SLAB_HWCACHE_ALIGN,
 281                                   NULL);
 282         if (!svc_rdma_ctxt_cachep) {
 283                 printk(KERN_INFO "Could not allocate WR ctxt cache.\n");
 284                 goto err1;
 285         }
 286
 287         /* Register RDMA with the SVC transport switch */
 288         svc_reg_xprt_class(&svc_rdma_class);
 289         return 0;
 290  err1:
 291         kmem_cache_destroy(svc_rdma_map_cachep);
 292  err0:
 293         unregister_sysctl_table(svcrdma_table_header);
 294         destroy_workqueue(svc_rdma_wq);
 295         return -ENOMEM;
 296 }
 297 MODULE_AUTHOR("Tom Tucker <tom@opengridcomputing.com>");
 298 MODULE_DESCRIPTION("SVC RDMA Transport");
 299 MODULE_LICENSE("Dual BSD/GPL");
 300 module_init(svc_rdma_init);
 301 module_exit(svc_rdma_cleanup);