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