net/sunrpc/xprtrdma/transport.c

   1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
   2 /*
   3  * Copyright (c) 2014-2017 Oracle.  All rights reserved.
   4  * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
   5  *
   6  * This software is available to you under a choice of one of two
   7  * licenses.  You may choose to be licensed under the terms of the GNU
   8  * General Public License (GPL) Version 2, available from the file
   9  * COPYING in the main directory of this source tree, or the BSD-type
  10  * license below:
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  *
  16  *      Redistributions of source code must retain the above copyright
  17  *      notice, this list of conditions and the following disclaimer.
  18  *
  19  *      Redistributions in binary form must reproduce the above
  20  *      copyright notice, this list of conditions and the following
  21  *      disclaimer in the documentation and/or other materials provided
  22  *      with the distribution.
  23  *
  24  *      Neither the name of the Network Appliance, Inc. nor the names of
  25  *      its contributors may be used to endorse or promote products
  26  *      derived from this software without specific prior written
  27  *      permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  30  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  31  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  32  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  33  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  34  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  35  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  36  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  37  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  38  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  39  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  40  */
  41
  42 /*
  43  * transport.c
  44  *
  45  * This file contains the top-level implementation of an RPC RDMA
  46  * transport.
  47  *
  48  * Naming convention: functions beginning with xprt_ are part of the
  49  * transport switch. All others are RPC RDMA internal.
  50  */
  51
  52 #include <linux/module.h>
  53 #include <linux/slab.h>
  54 #include <linux/seq_file.h>
  55 #include <linux/smp.h>
  56
  57 #include <linux/sunrpc/addr.h>
  58 #include <linux/sunrpc/svc_rdma.h>
  59
  60 #include "xprt_rdma.h"
  61 #include <trace/events/rpcrdma.h>
  62
  63 /*
  64  * tunables
  65  */
  66
  67 static unsigned int xprt_rdma_slot_table_entries = RPCRDMA_DEF_SLOT_TABLE;
  68 unsigned int xprt_rdma_max_inline_read = RPCRDMA_DEF_INLINE;
  69 unsigned int xprt_rdma_max_inline_write = RPCRDMA_DEF_INLINE;
  70 unsigned int xprt_rdma_memreg_strategy          = RPCRDMA_FRWR;
  71 int xprt_rdma_pad_optimize;
  72 static struct xprt_class xprt_rdma;
  73
  74 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  75
  76 static unsigned int min_slot_table_size = RPCRDMA_MIN_SLOT_TABLE;
  77 static unsigned int max_slot_table_size = RPCRDMA_MAX_SLOT_TABLE;
  78 static unsigned int min_inline_size = RPCRDMA_MIN_INLINE;
  79 static unsigned int max_inline_size = RPCRDMA_MAX_INLINE;
  80 static unsigned int max_padding = PAGE_SIZE;
  81 static unsigned int min_memreg = RPCRDMA_BOUNCEBUFFERS;
  82 static unsigned int max_memreg = RPCRDMA_LAST - 1;
  83 static unsigned int dummy;
  84
  85 static struct ctl_table_header *sunrpc_table_header;
  86
  87 static struct ctl_table xr_tunables_table[] = {
  88         {
  89                 .procname       = "rdma_slot_table_entries",
  90                 .data           = &xprt_rdma_slot_table_entries,
  91                 .maxlen         = sizeof(unsigned int),
  92                 .mode           = 0644,
  93                 .proc_handler   = proc_dointvec_minmax,
  94                 .extra1         = &min_slot_table_size,
  95                 .extra2         = &max_slot_table_size
  96         },
  97         {
  98                 .procname       = "rdma_max_inline_read",
  99                 .data           = &xprt_rdma_max_inline_read,
 100                 .maxlen         = sizeof(unsigned int),
 101                 .mode           = 0644,
 102                 .proc_handler   = proc_dointvec_minmax,
 103                 .extra1         = &min_inline_size,
 104                 .extra2         = &max_inline_size,
 105         },
 106         {
 107                 .procname       = "rdma_max_inline_write",
 108                 .data           = &xprt_rdma_max_inline_write,
 109                 .maxlen         = sizeof(unsigned int),
 110                 .mode           = 0644,
 111                 .proc_handler   = proc_dointvec_minmax,
 112                 .extra1         = &min_inline_size,
 113                 .extra2         = &max_inline_size,
 114         },
 115         {
 116                 .procname       = "rdma_inline_write_padding",
 117                 .data           = &dummy,
 118                 .maxlen         = sizeof(unsigned int),
 119                 .mode           = 0644,
 120                 .proc_handler   = proc_dointvec_minmax,
 121                 .extra1         = SYSCTL_ZERO,
 122                 .extra2         = &max_padding,
 123         },
 124         {
 125                 .procname       = "rdma_memreg_strategy",
 126                 .data           = &xprt_rdma_memreg_strategy,
 127                 .maxlen         = sizeof(unsigned int),
 128                 .mode           = 0644,
 129                 .proc_handler   = proc_dointvec_minmax,
 130                 .extra1         = &min_memreg,
 131                 .extra2         = &max_memreg,
 132         },
 133         {
 134                 .procname       = "rdma_pad_optimize",
 135                 .data           = &xprt_rdma_pad_optimize,
 136                 .maxlen         = sizeof(unsigned int),
 137                 .mode           = 0644,
 138                 .proc_handler   = proc_dointvec,
 139         },
 140         { },
 141 };
 142
 143 static struct ctl_table sunrpc_table[] = {
 144         {
 145                 .procname       = "sunrpc",
 146                 .mode           = 0555,
 147                 .child          = xr_tunables_table
 148         },
 149         { },
 150 };
 151
 152 #endif
 153
 154 static const struct rpc_xprt_ops xprt_rdma_procs;
 155
 156 static void
 157 xprt_rdma_format_addresses4(struct rpc_xprt *xprt, struct sockaddr *sap)
 158 {
 159         struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 160         char buf[20];
 161
 162         snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 163         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 164
 165         xprt->address_strings[RPC_DISPLAY_NETID] = RPCBIND_NETID_RDMA;
 166 }
 167
 168 static void
 169 xprt_rdma_format_addresses6(struct rpc_xprt *xprt, struct sockaddr *sap)
 170 {
 171         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 172         char buf[40];
 173
 174         snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 175         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 176
 177         xprt->address_strings[RPC_DISPLAY_NETID] = RPCBIND_NETID_RDMA6;
 178 }
 179
 180 void
 181 xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap)
 182 {
 183         char buf[128];
 184
 185         switch (sap->sa_family) {
 186         case AF_INET:
 187                 xprt_rdma_format_addresses4(xprt, sap);
 188                 break;
 189         case AF_INET6:
 190                 xprt_rdma_format_addresses6(xprt, sap);
 191                 break;
 192         default:
 193                 pr_err("rpcrdma: Unrecognized address family\n");
 194                 return;
 195         }
 196
 197         (void)rpc_ntop(sap, buf, sizeof(buf));
 198         xprt->address_strings[RPC_DISPLAY_ADDR] = kstrdup(buf, GFP_KERNEL);
 199
 200         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 201         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 202
 203         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 204         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 205
 206         xprt->address_strings[RPC_DISPLAY_PROTO] = "rdma";
 207 }
 208
 209 void
 210 xprt_rdma_free_addresses(struct rpc_xprt *xprt)
 211 {
 212         unsigned int i;
 213
 214         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 215                 switch (i) {
 216                 case RPC_DISPLAY_PROTO:
 217                 case RPC_DISPLAY_NETID:
 218                         continue;
 219                 default:
 220                         kfree(xprt->address_strings[i]);
 221                 }
 222 }
 223
 224 /**
 225  * xprt_rdma_connect_worker - establish connection in the background
 226  * @work: worker thread context
 227  *
 228  * Requester holds the xprt's send lock to prevent activity on this
 229  * transport while a fresh connection is being established. RPC tasks
 230  * sleep on the xprt's pending queue waiting for connect to complete.
 231  */
 232 static void
 233 xprt_rdma_connect_worker(struct work_struct *work)
 234 {
 235         struct rpcrdma_xprt *r_xprt = container_of(work, struct rpcrdma_xprt,
 236                                                    rx_connect_worker.work);
 237         struct rpc_xprt *xprt = &r_xprt->rx_xprt;
 238         unsigned int pflags = current->flags;
 239         int rc;
 240
 241         if (atomic_read(&xprt->swapper))
 242                 current->flags |= PF_MEMALLOC;
 243         rc = rpcrdma_xprt_connect(r_xprt);
 244         xprt_clear_connecting(xprt);
 245         if (!rc) {
 246                 xprt->connect_cookie++;
 247                 xprt->stat.connect_count++;
 248                 xprt->stat.connect_time += (long)jiffies -
 249                                            xprt->stat.connect_start;
 250                 xprt_set_connected(xprt);
 251                 rc = -EAGAIN;
 252         } else
 253                 rpcrdma_xprt_disconnect(r_xprt);
 254         xprt_unlock_connect(xprt, r_xprt);
 255         xprt_wake_pending_tasks(xprt, rc);
 256         current_restore_flags(pflags, PF_MEMALLOC);
 257 }
 258
 259 /**
 260  * xprt_rdma_inject_disconnect - inject a connection fault
 261  * @xprt: transport context
 262  *
 263  * If @xprt is connected, disconnect it to simulate spurious
 264  * connection loss. Caller must hold @xprt's send lock to
 265  * ensure that data structures and hardware resources are
 266  * stable during the rdma_disconnect() call.
 267  */
 268 static void
 269 xprt_rdma_inject_disconnect(struct rpc_xprt *xprt)
 270 {
 271         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 272
 273         trace_xprtrdma_op_inject_dsc(r_xprt);
 274         rdma_disconnect(r_xprt->rx_ep->re_id);
 275 }
 276
 277 /**
 278  * xprt_rdma_destroy - Full tear down of transport
 279  * @xprt: doomed transport context
 280  *
 281  * Caller guarantees there will be no more calls to us with
 282  * this @xprt.
 283  */
 284 static void
 285 xprt_rdma_destroy(struct rpc_xprt *xprt)
 286 {
 287         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 288
 289         cancel_delayed_work_sync(&r_xprt->rx_connect_worker);
 290
 291         rpcrdma_xprt_disconnect(r_xprt);
 292         rpcrdma_buffer_destroy(&r_xprt->rx_buf);
 293
 294         xprt_rdma_free_addresses(xprt);
 295         xprt_free(xprt);
 296
 297         module_put(THIS_MODULE);
 298 }
 299
 300 /* 60 second timeout, no retries */
 301 static const struct rpc_timeout xprt_rdma_default_timeout = {
 302         .to_initval = 60 * HZ,
 303         .to_maxval = 60 * HZ,
 304 };
 305
 306 /**
 307  * xprt_setup_rdma - Set up transport to use RDMA
 308  *
 309  * @args: rpc transport arguments
 310  */
 311 static struct rpc_xprt *
 312 xprt_setup_rdma(struct xprt_create *args)
 313 {
 314         struct rpc_xprt *xprt;
 315         struct rpcrdma_xprt *new_xprt;
 316         struct sockaddr *sap;
 317         int rc;
 318
 319         if (args->addrlen > sizeof(xprt->addr))
 320                 return ERR_PTR(-EBADF);
 321
 322         if (!try_module_get(THIS_MODULE))
 323                 return ERR_PTR(-EIO);
 324
 325         xprt = xprt_alloc(args->net, sizeof(struct rpcrdma_xprt), 0,
 326                           xprt_rdma_slot_table_entries);
 327         if (!xprt) {
 328                 module_put(THIS_MODULE);
 329                 return ERR_PTR(-ENOMEM);
 330         }
 331
 332         xprt->timeout = &xprt_rdma_default_timeout;
 333         xprt->connect_timeout = xprt->timeout->to_initval;
 334         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
 335         xprt->bind_timeout = RPCRDMA_BIND_TO;
 336         xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO;
 337         xprt->idle_timeout = RPCRDMA_IDLE_DISC_TO;
 338
 339         xprt->resvport = 0;             /* privileged port not needed */
 340         xprt->ops = &xprt_rdma_procs;
 341
 342         /*
 343          * Set up RDMA-specific connect data.
 344          */
 345         sap = args->dstaddr;
 346
 347         /* Ensure xprt->addr holds valid server TCP (not RDMA)
 348          * address, for any side protocols which peek at it */
 349         xprt->prot = IPPROTO_TCP;
 350         xprt->xprt_class = &xprt_rdma;
 351         xprt->addrlen = args->addrlen;
 352         memcpy(&xprt->addr, sap, xprt->addrlen);
 353
 354         if (rpc_get_port(sap))
 355                 xprt_set_bound(xprt);
 356         xprt_rdma_format_addresses(xprt, sap);
 357
 358         new_xprt = rpcx_to_rdmax(xprt);
 359         rc = rpcrdma_buffer_create(new_xprt);
 360         if (rc) {
 361                 xprt_rdma_free_addresses(xprt);
 362                 xprt_free(xprt);
 363                 module_put(THIS_MODULE);
 364                 return ERR_PTR(rc);
 365         }
 366
 367         INIT_DELAYED_WORK(&new_xprt->rx_connect_worker,
 368                           xprt_rdma_connect_worker);
 369
 370         xprt->max_payload = RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT;
 371
 372         return xprt;
 373 }
 374
 375 /**
 376  * xprt_rdma_close - close a transport connection
 377  * @xprt: transport context
 378  *
 379  * Called during autoclose or device removal.
 380  *
 381  * Caller holds @xprt's send lock to prevent activity on this
 382  * transport while the connection is torn down.
 383  */
 384 void xprt_rdma_close(struct rpc_xprt *xprt)
 385 {
 386         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 387
 388         rpcrdma_xprt_disconnect(r_xprt);
 389
 390         xprt->reestablish_timeout = 0;
 391         ++xprt->connect_cookie;
 392         xprt_disconnect_done(xprt);
 393 }
 394
 395 /**
 396  * xprt_rdma_set_port - update server port with rpcbind result
 397  * @xprt: controlling RPC transport
 398  * @port: new port value
 399  *
 400  * Transport connect status is unchanged.
 401  */
 402 static void
 403 xprt_rdma_set_port(struct rpc_xprt *xprt, u16 port)
 404 {
 405         struct sockaddr *sap = (struct sockaddr *)&xprt->addr;
 406         char buf[8];
 407
 408         rpc_set_port(sap, port);
 409
 410         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 411         snprintf(buf, sizeof(buf), "%u", port);
 412         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 413
 414         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 415         snprintf(buf, sizeof(buf), "%4hx", port);
 416         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 417 }
 418
 419 /**
 420  * xprt_rdma_timer - invoked when an RPC times out
 421  * @xprt: controlling RPC transport
 422  * @task: RPC task that timed out
 423  *
 424  * Invoked when the transport is still connected, but an RPC
 425  * retransmit timeout occurs.
 426  *
 427  * Since RDMA connections don't have a keep-alive, forcibly
 428  * disconnect and retry to connect. This drives full
 429  * detection of the network path, and retransmissions of
 430  * all pending RPCs.
 431  */
 432 static void
 433 xprt_rdma_timer(struct rpc_xprt *xprt, struct rpc_task *task)
 434 {
 435         xprt_force_disconnect(xprt);
 436 }
 437
 438 /**
 439  * xprt_rdma_set_connect_timeout - set timeouts for establishing a connection
 440  * @xprt: controlling transport instance
 441  * @connect_timeout: reconnect timeout after client disconnects
 442  * @reconnect_timeout: reconnect timeout after server disconnects
 443  *
 444  */
 445 static void xprt_rdma_set_connect_timeout(struct rpc_xprt *xprt,
 446                                           unsigned long connect_timeout,
 447                                           unsigned long reconnect_timeout)
 448 {
 449         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 450
 451         trace_xprtrdma_op_set_cto(r_xprt, connect_timeout, reconnect_timeout);
 452
 453         spin_lock(&xprt->transport_lock);
 454
 455         if (connect_timeout < xprt->connect_timeout) {
 456                 struct rpc_timeout to;
 457                 unsigned long initval;
 458
 459                 to = *xprt->timeout;
 460                 initval = connect_timeout;
 461                 if (initval < RPCRDMA_INIT_REEST_TO << 1)
 462                         initval = RPCRDMA_INIT_REEST_TO << 1;
 463                 to.to_initval = initval;
 464                 to.to_maxval = initval;
 465                 r_xprt->rx_timeout = to;
 466                 xprt->timeout = &r_xprt->rx_timeout;
 467                 xprt->connect_timeout = connect_timeout;
 468         }
 469
 470         if (reconnect_timeout < xprt->max_reconnect_timeout)
 471                 xprt->max_reconnect_timeout = reconnect_timeout;
 472
 473         spin_unlock(&xprt->transport_lock);
 474 }
 475
 476 /**
 477  * xprt_rdma_connect - schedule an attempt to reconnect
 478  * @xprt: transport state
 479  * @task: RPC scheduler context (unused)
 480  *
 481  */
 482 static void
 483 xprt_rdma_connect(struct rpc_xprt *xprt, struct rpc_task *task)
 484 {
 485         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 486         struct rpcrdma_ep *ep = r_xprt->rx_ep;
 487         unsigned long delay;
 488
 489         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, r_xprt));
 490
 491         delay = 0;
 492         if (ep && ep->re_connect_status != 0) {
 493                 delay = xprt_reconnect_delay(xprt);
 494                 xprt_reconnect_backoff(xprt, RPCRDMA_INIT_REEST_TO);
 495         }
 496         trace_xprtrdma_op_connect(r_xprt, delay);
 497         queue_delayed_work(system_long_wq, &r_xprt->rx_connect_worker, delay);
 498 }
 499
 500 /**
 501  * xprt_rdma_alloc_slot - allocate an rpc_rqst
 502  * @xprt: controlling RPC transport
 503  * @task: RPC task requesting a fresh rpc_rqst
 504  *
 505  * tk_status values:
 506  *      %0 if task->tk_rqstp points to a fresh rpc_rqst
 507  *      %-EAGAIN if no rpc_rqst is available; queued on backlog
 508  */
 509 static void
 510 xprt_rdma_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task)
 511 {
 512         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 513         struct rpcrdma_req *req;
 514
 515         req = rpcrdma_buffer_get(&r_xprt->rx_buf);
 516         if (!req)
 517                 goto out_sleep;
 518         task->tk_rqstp = &req->rl_slot;
 519         task->tk_status = 0;
 520         return;
 521
 522 out_sleep:
 523         task->tk_status = -ENOMEM;
 524         xprt_add_backlog(xprt, task);
 525 }
 526
 527 /**
 528  * xprt_rdma_free_slot - release an rpc_rqst
 529  * @xprt: controlling RPC transport
 530  * @rqst: rpc_rqst to release
 531  *
 532  */
 533 static void
 534 xprt_rdma_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *rqst)
 535 {
 536         struct rpcrdma_xprt *r_xprt =
 537                 container_of(xprt, struct rpcrdma_xprt, rx_xprt);
 538
 539         rpcrdma_reply_put(&r_xprt->rx_buf, rpcr_to_rdmar(rqst));
 540         if (!xprt_wake_up_backlog(xprt, rqst)) {
 541                 memset(rqst, 0, sizeof(*rqst));
 542                 rpcrdma_buffer_put(&r_xprt->rx_buf, rpcr_to_rdmar(rqst));
 543         }
 544 }
 545
 546 static bool rpcrdma_check_regbuf(struct rpcrdma_xprt *r_xprt,
 547                                  struct rpcrdma_regbuf *rb, size_t size,
 548                                  gfp_t flags)
 549 {
 550         if (unlikely(rdmab_length(rb) < size)) {
 551                 if (!rpcrdma_regbuf_realloc(rb, size, flags))
 552                         return false;
 553                 r_xprt->rx_stats.hardway_register_count += size;
 554         }
 555         return true;
 556 }
 557
 558 /**
 559  * xprt_rdma_allocate - allocate transport resources for an RPC
 560  * @task: RPC task
 561  *
 562  * Return values:
 563  *        0:    Success; rq_buffer points to RPC buffer to use
 564  *   ENOMEM:    Out of memory, call again later
 565  *      EIO:    A permanent error occurred, do not retry
 566  */
 567 static int
 568 xprt_rdma_allocate(struct rpc_task *task)
 569 {
 570         struct rpc_rqst *rqst = task->tk_rqstp;
 571         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt);
 572         struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
 573         gfp_t flags = rpc_task_gfp_mask();
 574
 575         if (!rpcrdma_check_regbuf(r_xprt, req->rl_sendbuf, rqst->rq_callsize,
 576                                   flags))
 577                 goto out_fail;
 578         if (!rpcrdma_check_regbuf(r_xprt, req->rl_recvbuf, rqst->rq_rcvsize,
 579                                   flags))
 580                 goto out_fail;
 581
 582         rqst->rq_buffer = rdmab_data(req->rl_sendbuf);
 583         rqst->rq_rbuffer = rdmab_data(req->rl_recvbuf);
 584         return 0;
 585
 586 out_fail:
 587         return -ENOMEM;
 588 }
 589
 590 /**
 591  * xprt_rdma_free - release resources allocated by xprt_rdma_allocate
 592  * @task: RPC task
 593  *
 594  * Caller guarantees rqst->rq_buffer is non-NULL.
 595  */
 596 static void
 597 xprt_rdma_free(struct rpc_task *task)
 598 {
 599         struct rpc_rqst *rqst = task->tk_rqstp;
 600         struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
 601
 602         if (unlikely(!list_empty(&req->rl_registered))) {
 603                 trace_xprtrdma_mrs_zap(task);
 604                 frwr_unmap_sync(rpcx_to_rdmax(rqst->rq_xprt), req);
 605         }
 606
 607         /* XXX: If the RPC is completing because of a signal and
 608          * not because a reply was received, we ought to ensure
 609          * that the Send completion has fired, so that memory
 610          * involved with the Send is not still visible to the NIC.
 611          */
 612 }
 613
 614 /**
 615  * xprt_rdma_send_request - marshal and send an RPC request
 616  * @rqst: RPC message in rq_snd_buf
 617  *
 618  * Caller holds the transport's write lock.
 619  *
 620  * Returns:
 621  *      %0 if the RPC message has been sent
 622  *      %-ENOTCONN if the caller should reconnect and call again
 623  *      %-EAGAIN if the caller should call again
 624  *      %-ENOBUFS if the caller should call again after a delay
 625  *      %-EMSGSIZE if encoding ran out of buffer space. The request
 626  *              was not sent. Do not try to send this message again.
 627  *      %-EIO if an I/O error occurred. The request was not sent.
 628  *              Do not try to send this message again.
 629  */
 630 static int
 631 xprt_rdma_send_request(struct rpc_rqst *rqst)
 632 {
 633         struct rpc_xprt *xprt = rqst->rq_xprt;
 634         struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
 635         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 636         int rc = 0;
 637
 638 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 639         if (unlikely(!rqst->rq_buffer))
 640                 return xprt_rdma_bc_send_reply(rqst);
 641 #endif  /* CONFIG_SUNRPC_BACKCHANNEL */
 642
 643         if (!xprt_connected(xprt))
 644                 return -ENOTCONN;
 645
 646         if (!xprt_request_get_cong(xprt, rqst))
 647                 return -EBADSLT;
 648
 649         rc = rpcrdma_marshal_req(r_xprt, rqst);
 650         if (rc < 0)
 651                 goto failed_marshal;
 652
 653         /* Must suppress retransmit to maintain credits */
 654         if (rqst->rq_connect_cookie == xprt->connect_cookie)
 655                 goto drop_connection;
 656         rqst->rq_xtime = ktime_get();
 657
 658         if (frwr_send(r_xprt, req))
 659                 goto drop_connection;
 660
 661         rqst->rq_xmit_bytes_sent += rqst->rq_snd_buf.len;
 662
 663         /* An RPC with no reply will throw off credit accounting,
 664          * so drop the connection to reset the credit grant.
 665          */
 666         if (!rpc_reply_expected(rqst->rq_task))
 667                 goto drop_connection;
 668         return 0;
 669
 670 failed_marshal:
 671         if (rc != -ENOTCONN)
 672                 return rc;
 673 drop_connection:
 674         xprt_rdma_close(xprt);
 675         return -ENOTCONN;
 676 }
 677
 678 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
 679 {
 680         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 681         long idle_time = 0;
 682
 683         if (xprt_connected(xprt))
 684                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
 685
 686         seq_puts(seq, "\txprt:\trdma ");
 687         seq_printf(seq, "%u %lu %lu %lu %ld %lu %lu %lu %llu %llu ",
 688                    0,   /* need a local port? */
 689                    xprt->stat.bind_count,
 690                    xprt->stat.connect_count,
 691                    xprt->stat.connect_time / HZ,
 692                    idle_time,
 693                    xprt->stat.sends,
 694                    xprt->stat.recvs,
 695                    xprt->stat.bad_xids,
 696                    xprt->stat.req_u,
 697                    xprt->stat.bklog_u);
 698         seq_printf(seq, "%lu %lu %lu %llu %llu %llu %llu %lu %lu %lu %lu ",
 699                    r_xprt->rx_stats.read_chunk_count,
 700                    r_xprt->rx_stats.write_chunk_count,
 701                    r_xprt->rx_stats.reply_chunk_count,
 702                    r_xprt->rx_stats.total_rdma_request,
 703                    r_xprt->rx_stats.total_rdma_reply,
 704                    r_xprt->rx_stats.pullup_copy_count,
 705                    r_xprt->rx_stats.fixup_copy_count,
 706                    r_xprt->rx_stats.hardway_register_count,
 707                    r_xprt->rx_stats.failed_marshal_count,
 708                    r_xprt->rx_stats.bad_reply_count,
 709                    r_xprt->rx_stats.nomsg_call_count);
 710         seq_printf(seq, "%lu %lu %lu %lu %lu %lu\n",
 711                    r_xprt->rx_stats.mrs_recycled,
 712                    r_xprt->rx_stats.mrs_orphaned,
 713                    r_xprt->rx_stats.mrs_allocated,
 714                    r_xprt->rx_stats.local_inv_needed,
 715                    r_xprt->rx_stats.empty_sendctx_q,
 716                    r_xprt->rx_stats.reply_waits_for_send);
 717 }
 718
 719 static int
 720 xprt_rdma_enable_swap(struct rpc_xprt *xprt)
 721 {
 722         return 0;
 723 }
 724
 725 static void
 726 xprt_rdma_disable_swap(struct rpc_xprt *xprt)
 727 {
 728 }
 729
 730 /*
 731  * Plumbing for rpc transport switch and kernel module
 732  */
 733
 734 static const struct rpc_xprt_ops xprt_rdma_procs = {
 735         .reserve_xprt           = xprt_reserve_xprt_cong,
 736         .release_xprt           = xprt_release_xprt_cong, /* sunrpc/xprt.c */
 737         .alloc_slot             = xprt_rdma_alloc_slot,
 738         .free_slot              = xprt_rdma_free_slot,
 739         .release_request        = xprt_release_rqst_cong,       /* ditto */
 740         .wait_for_reply_request = xprt_wait_for_reply_request_def, /* ditto */
 741         .timer                  = xprt_rdma_timer,
 742         .rpcbind                = rpcb_getport_async,   /* sunrpc/rpcb_clnt.c */
 743         .set_port               = xprt_rdma_set_port,
 744         .connect                = xprt_rdma_connect,
 745         .buf_alloc              = xprt_rdma_allocate,
 746         .buf_free               = xprt_rdma_free,
 747         .send_request           = xprt_rdma_send_request,
 748         .close                  = xprt_rdma_close,
 749         .destroy                = xprt_rdma_destroy,
 750         .set_connect_timeout    = xprt_rdma_set_connect_timeout,
 751         .print_stats            = xprt_rdma_print_stats,
 752         .enable_swap            = xprt_rdma_enable_swap,
 753         .disable_swap           = xprt_rdma_disable_swap,
 754         .inject_disconnect      = xprt_rdma_inject_disconnect,
 755 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 756         .bc_setup               = xprt_rdma_bc_setup,
 757         .bc_maxpayload          = xprt_rdma_bc_maxpayload,
 758         .bc_num_slots           = xprt_rdma_bc_max_slots,
 759         .bc_free_rqst           = xprt_rdma_bc_free_rqst,
 760         .bc_destroy             = xprt_rdma_bc_destroy,
 761 #endif
 762 };
 763
 764 static struct xprt_class xprt_rdma = {
 765         .list                   = LIST_HEAD_INIT(xprt_rdma.list),
 766         .name                   = "rdma",
 767         .owner                  = THIS_MODULE,
 768         .ident                  = XPRT_TRANSPORT_RDMA,
 769         .setup                  = xprt_setup_rdma,
 770         .netid                  = { "rdma", "rdma6", "" },
 771 };
 772
 773 void xprt_rdma_cleanup(void)
 774 {
 775 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 776         if (sunrpc_table_header) {
 777                 unregister_sysctl_table(sunrpc_table_header);
 778                 sunrpc_table_header = NULL;
 779         }
 780 #endif
 781
 782         xprt_unregister_transport(&xprt_rdma);
 783         xprt_unregister_transport(&xprt_rdma_bc);
 784 }
 785
 786 int xprt_rdma_init(void)
 787 {
 788         int rc;
 789
 790         rc = xprt_register_transport(&xprt_rdma);
 791         if (rc)
 792                 return rc;
 793
 794         rc = xprt_register_transport(&xprt_rdma_bc);
 795         if (rc) {
 796                 xprt_unregister_transport(&xprt_rdma);
 797                 return rc;
 798         }
 799
 800 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 801         if (!sunrpc_table_header)
 802                 sunrpc_table_header = register_sysctl_table(sunrpc_table);
 803 #endif
 804         return 0;
 805 }