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 #endif
 143
 144 static const struct rpc_xprt_ops xprt_rdma_procs;
 145
 146 static void
 147 xprt_rdma_format_addresses4(struct rpc_xprt *xprt, struct sockaddr *sap)
 148 {
 149         struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 150         char buf[20];
 151
 152         snprintf(buf, sizeof(buf), "%08x", ntohl(sin->sin_addr.s_addr));
 153         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 154
 155         xprt->address_strings[RPC_DISPLAY_NETID] = RPCBIND_NETID_RDMA;
 156 }
 157
 158 static void
 159 xprt_rdma_format_addresses6(struct rpc_xprt *xprt, struct sockaddr *sap)
 160 {
 161         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 162         char buf[40];
 163
 164         snprintf(buf, sizeof(buf), "%pi6", &sin6->sin6_addr);
 165         xprt->address_strings[RPC_DISPLAY_HEX_ADDR] = kstrdup(buf, GFP_KERNEL);
 166
 167         xprt->address_strings[RPC_DISPLAY_NETID] = RPCBIND_NETID_RDMA6;
 168 }
 169
 170 void
 171 xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap)
 172 {
 173         char buf[128];
 174
 175         switch (sap->sa_family) {
 176         case AF_INET:
 177                 xprt_rdma_format_addresses4(xprt, sap);
 178                 break;
 179         case AF_INET6:
 180                 xprt_rdma_format_addresses6(xprt, sap);
 181                 break;
 182         default:
 183                 pr_err("rpcrdma: Unrecognized address family\n");
 184                 return;
 185         }
 186
 187         (void)rpc_ntop(sap, buf, sizeof(buf));
 188         xprt->address_strings[RPC_DISPLAY_ADDR] = kstrdup(buf, GFP_KERNEL);
 189
 190         snprintf(buf, sizeof(buf), "%u", rpc_get_port(sap));
 191         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 192
 193         snprintf(buf, sizeof(buf), "%4hx", rpc_get_port(sap));
 194         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 195
 196         xprt->address_strings[RPC_DISPLAY_PROTO] = "rdma";
 197 }
 198
 199 void
 200 xprt_rdma_free_addresses(struct rpc_xprt *xprt)
 201 {
 202         unsigned int i;
 203
 204         for (i = 0; i < RPC_DISPLAY_MAX; i++)
 205                 switch (i) {
 206                 case RPC_DISPLAY_PROTO:
 207                 case RPC_DISPLAY_NETID:
 208                         continue;
 209                 default:
 210                         kfree(xprt->address_strings[i]);
 211                 }
 212 }
 213
 214 /**
 215  * xprt_rdma_connect_worker - establish connection in the background
 216  * @work: worker thread context
 217  *
 218  * Requester holds the xprt's send lock to prevent activity on this
 219  * transport while a fresh connection is being established. RPC tasks
 220  * sleep on the xprt's pending queue waiting for connect to complete.
 221  */
 222 static void
 223 xprt_rdma_connect_worker(struct work_struct *work)
 224 {
 225         struct rpcrdma_xprt *r_xprt = container_of(work, struct rpcrdma_xprt,
 226                                                    rx_connect_worker.work);
 227         struct rpc_xprt *xprt = &r_xprt->rx_xprt;
 228         unsigned int pflags = current->flags;
 229         int rc;
 230
 231         if (atomic_read(&xprt->swapper))
 232                 current->flags |= PF_MEMALLOC;
 233         rc = rpcrdma_xprt_connect(r_xprt);
 234         xprt_clear_connecting(xprt);
 235         if (!rc) {
 236                 xprt->connect_cookie++;
 237                 xprt->stat.connect_count++;
 238                 xprt->stat.connect_time += (long)jiffies -
 239                                            xprt->stat.connect_start;
 240                 xprt_set_connected(xprt);
 241                 rc = -EAGAIN;
 242         } else
 243                 rpcrdma_xprt_disconnect(r_xprt);
 244         xprt_unlock_connect(xprt, r_xprt);
 245         xprt_wake_pending_tasks(xprt, rc);
 246         current_restore_flags(pflags, PF_MEMALLOC);
 247 }
 248
 249 /**
 250  * xprt_rdma_inject_disconnect - inject a connection fault
 251  * @xprt: transport context
 252  *
 253  * If @xprt is connected, disconnect it to simulate spurious
 254  * connection loss. Caller must hold @xprt's send lock to
 255  * ensure that data structures and hardware resources are
 256  * stable during the rdma_disconnect() call.
 257  */
 258 static void
 259 xprt_rdma_inject_disconnect(struct rpc_xprt *xprt)
 260 {
 261         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 262
 263         trace_xprtrdma_op_inject_dsc(r_xprt);
 264         rdma_disconnect(r_xprt->rx_ep->re_id);
 265 }
 266
 267 /**
 268  * xprt_rdma_destroy - Full tear down of transport
 269  * @xprt: doomed transport context
 270  *
 271  * Caller guarantees there will be no more calls to us with
 272  * this @xprt.
 273  */
 274 static void
 275 xprt_rdma_destroy(struct rpc_xprt *xprt)
 276 {
 277         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 278
 279         cancel_delayed_work_sync(&r_xprt->rx_connect_worker);
 280
 281         rpcrdma_xprt_disconnect(r_xprt);
 282         rpcrdma_buffer_destroy(&r_xprt->rx_buf);
 283
 284         xprt_rdma_free_addresses(xprt);
 285         xprt_free(xprt);
 286
 287         module_put(THIS_MODULE);
 288 }
 289
 290 /* 60 second timeout, no retries */
 291 static const struct rpc_timeout xprt_rdma_default_timeout = {
 292         .to_initval = 60 * HZ,
 293         .to_maxval = 60 * HZ,
 294 };
 295
 296 /**
 297  * xprt_setup_rdma - Set up transport to use RDMA
 298  *
 299  * @args: rpc transport arguments
 300  */
 301 static struct rpc_xprt *
 302 xprt_setup_rdma(struct xprt_create *args)
 303 {
 304         struct rpc_xprt *xprt;
 305         struct rpcrdma_xprt *new_xprt;
 306         struct sockaddr *sap;
 307         int rc;
 308
 309         if (args->addrlen > sizeof(xprt->addr))
 310                 return ERR_PTR(-EBADF);
 311
 312         if (!try_module_get(THIS_MODULE))
 313                 return ERR_PTR(-EIO);
 314
 315         xprt = xprt_alloc(args->net, sizeof(struct rpcrdma_xprt), 0,
 316                           xprt_rdma_slot_table_entries);
 317         if (!xprt) {
 318                 module_put(THIS_MODULE);
 319                 return ERR_PTR(-ENOMEM);
 320         }
 321
 322         xprt->timeout = &xprt_rdma_default_timeout;
 323         xprt->connect_timeout = xprt->timeout->to_initval;
 324         xprt->max_reconnect_timeout = xprt->timeout->to_maxval;
 325         xprt->bind_timeout = RPCRDMA_BIND_TO;
 326         xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO;
 327         xprt->idle_timeout = RPCRDMA_IDLE_DISC_TO;
 328
 329         xprt->resvport = 0;             /* privileged port not needed */
 330         xprt->ops = &xprt_rdma_procs;
 331
 332         /*
 333          * Set up RDMA-specific connect data.
 334          */
 335         sap = args->dstaddr;
 336
 337         /* Ensure xprt->addr holds valid server TCP (not RDMA)
 338          * address, for any side protocols which peek at it */
 339         xprt->prot = IPPROTO_TCP;
 340         xprt->xprt_class = &xprt_rdma;
 341         xprt->addrlen = args->addrlen;
 342         memcpy(&xprt->addr, sap, xprt->addrlen);
 343
 344         if (rpc_get_port(sap))
 345                 xprt_set_bound(xprt);
 346         xprt_rdma_format_addresses(xprt, sap);
 347
 348         new_xprt = rpcx_to_rdmax(xprt);
 349         rc = rpcrdma_buffer_create(new_xprt);
 350         if (rc) {
 351                 xprt_rdma_free_addresses(xprt);
 352                 xprt_free(xprt);
 353                 module_put(THIS_MODULE);
 354                 return ERR_PTR(rc);
 355         }
 356
 357         INIT_DELAYED_WORK(&new_xprt->rx_connect_worker,
 358                           xprt_rdma_connect_worker);
 359
 360         xprt->max_payload = RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT;
 361
 362         return xprt;
 363 }
 364
 365 /**
 366  * xprt_rdma_close - close a transport connection
 367  * @xprt: transport context
 368  *
 369  * Called during autoclose or device removal.
 370  *
 371  * Caller holds @xprt's send lock to prevent activity on this
 372  * transport while the connection is torn down.
 373  */
 374 void xprt_rdma_close(struct rpc_xprt *xprt)
 375 {
 376         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 377
 378         rpcrdma_xprt_disconnect(r_xprt);
 379
 380         xprt->reestablish_timeout = 0;
 381         ++xprt->connect_cookie;
 382         xprt_disconnect_done(xprt);
 383 }
 384
 385 /**
 386  * xprt_rdma_set_port - update server port with rpcbind result
 387  * @xprt: controlling RPC transport
 388  * @port: new port value
 389  *
 390  * Transport connect status is unchanged.
 391  */
 392 static void
 393 xprt_rdma_set_port(struct rpc_xprt *xprt, u16 port)
 394 {
 395         struct sockaddr *sap = (struct sockaddr *)&xprt->addr;
 396         char buf[8];
 397
 398         rpc_set_port(sap, port);
 399
 400         kfree(xprt->address_strings[RPC_DISPLAY_PORT]);
 401         snprintf(buf, sizeof(buf), "%u", port);
 402         xprt->address_strings[RPC_DISPLAY_PORT] = kstrdup(buf, GFP_KERNEL);
 403
 404         kfree(xprt->address_strings[RPC_DISPLAY_HEX_PORT]);
 405         snprintf(buf, sizeof(buf), "%4hx", port);
 406         xprt->address_strings[RPC_DISPLAY_HEX_PORT] = kstrdup(buf, GFP_KERNEL);
 407 }
 408
 409 /**
 410  * xprt_rdma_timer - invoked when an RPC times out
 411  * @xprt: controlling RPC transport
 412  * @task: RPC task that timed out
 413  *
 414  * Invoked when the transport is still connected, but an RPC
 415  * retransmit timeout occurs.
 416  *
 417  * Since RDMA connections don't have a keep-alive, forcibly
 418  * disconnect and retry to connect. This drives full
 419  * detection of the network path, and retransmissions of
 420  * all pending RPCs.
 421  */
 422 static void
 423 xprt_rdma_timer(struct rpc_xprt *xprt, struct rpc_task *task)
 424 {
 425         xprt_force_disconnect(xprt);
 426 }
 427
 428 /**
 429  * xprt_rdma_set_connect_timeout - set timeouts for establishing a connection
 430  * @xprt: controlling transport instance
 431  * @connect_timeout: reconnect timeout after client disconnects
 432  * @reconnect_timeout: reconnect timeout after server disconnects
 433  *
 434  */
 435 static void xprt_rdma_set_connect_timeout(struct rpc_xprt *xprt,
 436                                           unsigned long connect_timeout,
 437                                           unsigned long reconnect_timeout)
 438 {
 439         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 440
 441         trace_xprtrdma_op_set_cto(r_xprt, connect_timeout, reconnect_timeout);
 442
 443         spin_lock(&xprt->transport_lock);
 444
 445         if (connect_timeout < xprt->connect_timeout) {
 446                 struct rpc_timeout to;
 447                 unsigned long initval;
 448
 449                 to = *xprt->timeout;
 450                 initval = connect_timeout;
 451                 if (initval < RPCRDMA_INIT_REEST_TO << 1)
 452                         initval = RPCRDMA_INIT_REEST_TO << 1;
 453                 to.to_initval = initval;
 454                 to.to_maxval = initval;
 455                 r_xprt->rx_timeout = to;
 456                 xprt->timeout = &r_xprt->rx_timeout;
 457                 xprt->connect_timeout = connect_timeout;
 458         }
 459
 460         if (reconnect_timeout < xprt->max_reconnect_timeout)
 461                 xprt->max_reconnect_timeout = reconnect_timeout;
 462
 463         spin_unlock(&xprt->transport_lock);
 464 }
 465
 466 /**
 467  * xprt_rdma_connect - schedule an attempt to reconnect
 468  * @xprt: transport state
 469  * @task: RPC scheduler context (unused)
 470  *
 471  */
 472 static void
 473 xprt_rdma_connect(struct rpc_xprt *xprt, struct rpc_task *task)
 474 {
 475         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 476         struct rpcrdma_ep *ep = r_xprt->rx_ep;
 477         unsigned long delay;
 478
 479         WARN_ON_ONCE(!xprt_lock_connect(xprt, task, r_xprt));
 480
 481         delay = 0;
 482         if (ep && ep->re_connect_status != 0) {
 483                 delay = xprt_reconnect_delay(xprt);
 484                 xprt_reconnect_backoff(xprt, RPCRDMA_INIT_REEST_TO);
 485         }
 486         trace_xprtrdma_op_connect(r_xprt, delay);
 487         queue_delayed_work(system_long_wq, &r_xprt->rx_connect_worker, delay);
 488 }
 489
 490 /**
 491  * xprt_rdma_alloc_slot - allocate an rpc_rqst
 492  * @xprt: controlling RPC transport
 493  * @task: RPC task requesting a fresh rpc_rqst
 494  *
 495  * tk_status values:
 496  *      %0 if task->tk_rqstp points to a fresh rpc_rqst
 497  *      %-EAGAIN if no rpc_rqst is available; queued on backlog
 498  */
 499 static void
 500 xprt_rdma_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task)
 501 {
 502         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 503         struct rpcrdma_req *req;
 504
 505         req = rpcrdma_buffer_get(&r_xprt->rx_buf);
 506         if (!req)
 507                 goto out_sleep;
 508         task->tk_rqstp = &req->rl_slot;
 509         task->tk_status = 0;
 510         return;
 511
 512 out_sleep:
 513         task->tk_status = -ENOMEM;
 514         xprt_add_backlog(xprt, task);
 515 }
 516
 517 /**
 518  * xprt_rdma_free_slot - release an rpc_rqst
 519  * @xprt: controlling RPC transport
 520  * @rqst: rpc_rqst to release
 521  *
 522  */
 523 static void
 524 xprt_rdma_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *rqst)
 525 {
 526         struct rpcrdma_xprt *r_xprt =
 527                 container_of(xprt, struct rpcrdma_xprt, rx_xprt);
 528
 529         rpcrdma_reply_put(&r_xprt->rx_buf, rpcr_to_rdmar(rqst));
 530         if (!xprt_wake_up_backlog(xprt, rqst)) {
 531                 memset(rqst, 0, sizeof(*rqst));
 532                 rpcrdma_buffer_put(&r_xprt->rx_buf, rpcr_to_rdmar(rqst));
 533         }
 534 }
 535
 536 static bool rpcrdma_check_regbuf(struct rpcrdma_xprt *r_xprt,
 537                                  struct rpcrdma_regbuf *rb, size_t size,
 538                                  gfp_t flags)
 539 {
 540         if (unlikely(rdmab_length(rb) < size)) {
 541                 if (!rpcrdma_regbuf_realloc(rb, size, flags))
 542                         return false;
 543                 r_xprt->rx_stats.hardway_register_count += size;
 544         }
 545         return true;
 546 }
 547
 548 /**
 549  * xprt_rdma_allocate - allocate transport resources for an RPC
 550  * @task: RPC task
 551  *
 552  * Return values:
 553  *        0:    Success; rq_buffer points to RPC buffer to use
 554  *   ENOMEM:    Out of memory, call again later
 555  *      EIO:    A permanent error occurred, do not retry
 556  */
 557 static int
 558 xprt_rdma_allocate(struct rpc_task *task)
 559 {
 560         struct rpc_rqst *rqst = task->tk_rqstp;
 561         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt);
 562         struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
 563         gfp_t flags = rpc_task_gfp_mask();
 564
 565         if (!rpcrdma_check_regbuf(r_xprt, req->rl_sendbuf, rqst->rq_callsize,
 566                                   flags))
 567                 goto out_fail;
 568         if (!rpcrdma_check_regbuf(r_xprt, req->rl_recvbuf, rqst->rq_rcvsize,
 569                                   flags))
 570                 goto out_fail;
 571
 572         rqst->rq_buffer = rdmab_data(req->rl_sendbuf);
 573         rqst->rq_rbuffer = rdmab_data(req->rl_recvbuf);
 574         return 0;
 575
 576 out_fail:
 577         return -ENOMEM;
 578 }
 579
 580 /**
 581  * xprt_rdma_free - release resources allocated by xprt_rdma_allocate
 582  * @task: RPC task
 583  *
 584  * Caller guarantees rqst->rq_buffer is non-NULL.
 585  */
 586 static void
 587 xprt_rdma_free(struct rpc_task *task)
 588 {
 589         struct rpc_rqst *rqst = task->tk_rqstp;
 590         struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
 591
 592         if (unlikely(!list_empty(&req->rl_registered))) {
 593                 trace_xprtrdma_mrs_zap(task);
 594                 frwr_unmap_sync(rpcx_to_rdmax(rqst->rq_xprt), req);
 595         }
 596
 597         /* XXX: If the RPC is completing because of a signal and
 598          * not because a reply was received, we ought to ensure
 599          * that the Send completion has fired, so that memory
 600          * involved with the Send is not still visible to the NIC.
 601          */
 602 }
 603
 604 /**
 605  * xprt_rdma_send_request - marshal and send an RPC request
 606  * @rqst: RPC message in rq_snd_buf
 607  *
 608  * Caller holds the transport's write lock.
 609  *
 610  * Returns:
 611  *      %0 if the RPC message has been sent
 612  *      %-ENOTCONN if the caller should reconnect and call again
 613  *      %-EAGAIN if the caller should call again
 614  *      %-ENOBUFS if the caller should call again after a delay
 615  *      %-EMSGSIZE if encoding ran out of buffer space. The request
 616  *              was not sent. Do not try to send this message again.
 617  *      %-EIO if an I/O error occurred. The request was not sent.
 618  *              Do not try to send this message again.
 619  */
 620 static int
 621 xprt_rdma_send_request(struct rpc_rqst *rqst)
 622 {
 623         struct rpc_xprt *xprt = rqst->rq_xprt;
 624         struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
 625         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 626         int rc = 0;
 627
 628 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 629         if (unlikely(!rqst->rq_buffer))
 630                 return xprt_rdma_bc_send_reply(rqst);
 631 #endif  /* CONFIG_SUNRPC_BACKCHANNEL */
 632
 633         if (!xprt_connected(xprt))
 634                 return -ENOTCONN;
 635
 636         if (!xprt_request_get_cong(xprt, rqst))
 637                 return -EBADSLT;
 638
 639         rc = rpcrdma_marshal_req(r_xprt, rqst);
 640         if (rc < 0)
 641                 goto failed_marshal;
 642
 643         /* Must suppress retransmit to maintain credits */
 644         if (rqst->rq_connect_cookie == xprt->connect_cookie)
 645                 goto drop_connection;
 646         rqst->rq_xtime = ktime_get();
 647
 648         if (frwr_send(r_xprt, req))
 649                 goto drop_connection;
 650
 651         rqst->rq_xmit_bytes_sent += rqst->rq_snd_buf.len;
 652
 653         /* An RPC with no reply will throw off credit accounting,
 654          * so drop the connection to reset the credit grant.
 655          */
 656         if (!rpc_reply_expected(rqst->rq_task))
 657                 goto drop_connection;
 658         return 0;
 659
 660 failed_marshal:
 661         if (rc != -ENOTCONN)
 662                 return rc;
 663 drop_connection:
 664         xprt_rdma_close(xprt);
 665         return -ENOTCONN;
 666 }
 667
 668 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
 669 {
 670         struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 671         long idle_time = 0;
 672
 673         if (xprt_connected(xprt))
 674                 idle_time = (long)(jiffies - xprt->last_used) / HZ;
 675
 676         seq_puts(seq, "\txprt:\trdma ");
 677         seq_printf(seq, "%u %lu %lu %lu %ld %lu %lu %lu %llu %llu ",
 678                    0,   /* need a local port? */
 679                    xprt->stat.bind_count,
 680                    xprt->stat.connect_count,
 681                    xprt->stat.connect_time / HZ,
 682                    idle_time,
 683                    xprt->stat.sends,
 684                    xprt->stat.recvs,
 685                    xprt->stat.bad_xids,
 686                    xprt->stat.req_u,
 687                    xprt->stat.bklog_u);
 688         seq_printf(seq, "%lu %lu %lu %llu %llu %llu %llu %lu %lu %lu %lu ",
 689                    r_xprt->rx_stats.read_chunk_count,
 690                    r_xprt->rx_stats.write_chunk_count,
 691                    r_xprt->rx_stats.reply_chunk_count,
 692                    r_xprt->rx_stats.total_rdma_request,
 693                    r_xprt->rx_stats.total_rdma_reply,
 694                    r_xprt->rx_stats.pullup_copy_count,
 695                    r_xprt->rx_stats.fixup_copy_count,
 696                    r_xprt->rx_stats.hardway_register_count,
 697                    r_xprt->rx_stats.failed_marshal_count,
 698                    r_xprt->rx_stats.bad_reply_count,
 699                    r_xprt->rx_stats.nomsg_call_count);
 700         seq_printf(seq, "%lu %lu %lu %lu %lu %lu\n",
 701                    r_xprt->rx_stats.mrs_recycled,
 702                    r_xprt->rx_stats.mrs_orphaned,
 703                    r_xprt->rx_stats.mrs_allocated,
 704                    r_xprt->rx_stats.local_inv_needed,
 705                    r_xprt->rx_stats.empty_sendctx_q,
 706                    r_xprt->rx_stats.reply_waits_for_send);
 707 }
 708
 709 static int
 710 xprt_rdma_enable_swap(struct rpc_xprt *xprt)
 711 {
 712         return 0;
 713 }
 714
 715 static void
 716 xprt_rdma_disable_swap(struct rpc_xprt *xprt)
 717 {
 718 }
 719
 720 /*
 721  * Plumbing for rpc transport switch and kernel module
 722  */
 723
 724 static const struct rpc_xprt_ops xprt_rdma_procs = {
 725         .reserve_xprt           = xprt_reserve_xprt_cong,
 726         .release_xprt           = xprt_release_xprt_cong, /* sunrpc/xprt.c */
 727         .alloc_slot             = xprt_rdma_alloc_slot,
 728         .free_slot              = xprt_rdma_free_slot,
 729         .release_request        = xprt_release_rqst_cong,       /* ditto */
 730         .wait_for_reply_request = xprt_wait_for_reply_request_def, /* ditto */
 731         .timer                  = xprt_rdma_timer,
 732         .rpcbind                = rpcb_getport_async,   /* sunrpc/rpcb_clnt.c */
 733         .set_port               = xprt_rdma_set_port,
 734         .connect                = xprt_rdma_connect,
 735         .buf_alloc              = xprt_rdma_allocate,
 736         .buf_free               = xprt_rdma_free,
 737         .send_request           = xprt_rdma_send_request,
 738         .close                  = xprt_rdma_close,
 739         .destroy                = xprt_rdma_destroy,
 740         .set_connect_timeout    = xprt_rdma_set_connect_timeout,
 741         .print_stats            = xprt_rdma_print_stats,
 742         .enable_swap            = xprt_rdma_enable_swap,
 743         .disable_swap           = xprt_rdma_disable_swap,
 744         .inject_disconnect      = xprt_rdma_inject_disconnect,
 745 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 746         .bc_setup               = xprt_rdma_bc_setup,
 747         .bc_maxpayload          = xprt_rdma_bc_maxpayload,
 748         .bc_num_slots           = xprt_rdma_bc_max_slots,
 749         .bc_free_rqst           = xprt_rdma_bc_free_rqst,
 750         .bc_destroy             = xprt_rdma_bc_destroy,
 751 #endif
 752 };
 753
 754 static struct xprt_class xprt_rdma = {
 755         .list                   = LIST_HEAD_INIT(xprt_rdma.list),
 756         .name                   = "rdma",
 757         .owner                  = THIS_MODULE,
 758         .ident                  = XPRT_TRANSPORT_RDMA,
 759         .setup                  = xprt_setup_rdma,
 760         .netid                  = { "rdma", "rdma6", "" },
 761 };
 762
 763 void xprt_rdma_cleanup(void)
 764 {
 765 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 766         if (sunrpc_table_header) {
 767                 unregister_sysctl_table(sunrpc_table_header);
 768                 sunrpc_table_header = NULL;
 769         }
 770 #endif
 771
 772         xprt_unregister_transport(&xprt_rdma);
 773         xprt_unregister_transport(&xprt_rdma_bc);
 774 }
 775
 776 int xprt_rdma_init(void)
 777 {
 778         int rc;
 779
 780         rc = xprt_register_transport(&xprt_rdma);
 781         if (rc)
 782                 return rc;
 783
 784         rc = xprt_register_transport(&xprt_rdma_bc);
 785         if (rc) {
 786                 xprt_unregister_transport(&xprt_rdma);
 787                 return rc;
 788         }
 789
 790 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 791         if (!sunrpc_table_header)
 792                 sunrpc_table_header = register_sysctl("sunrpc", xr_tunables_table);
 793 #endif
 794         return 0;
 795 }