1 /* 2 * Copyright (c) 2014-2017 Oracle. All rights reserved. 3 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the BSD-type 9 * license below: 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 15 * Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 18 * Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials provided 21 * with the distribution. 22 * 23 * Neither the name of the Network Appliance, Inc. nor the names of 24 * its contributors may be used to endorse or promote products 25 * derived from this software without specific prior written 26 * permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 39 */ 40 41 /* 42 * transport.c 43 * 44 * This file contains the top-level implementation of an RPC RDMA 45 * transport. 46 * 47 * Naming convention: functions beginning with xprt_ are part of the 48 * transport switch. All others are RPC RDMA internal. 49 */ 50 51 #include <linux/module.h> 52 #include <linux/slab.h> 53 #include <linux/seq_file.h> 54 #include <linux/sunrpc/addr.h> 55 #include <linux/smp.h> 56 57 #include "xprt_rdma.h" 58 59 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 60 # define RPCDBG_FACILITY RPCDBG_TRANS 61 #endif 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 static unsigned int xprt_rdma_max_inline_write = RPCRDMA_DEF_INLINE; 70 static unsigned int xprt_rdma_inline_write_padding; 71 unsigned int xprt_rdma_memreg_strategy = RPCRDMA_FRMR; 72 int xprt_rdma_pad_optimize; 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 zero; 81 static unsigned int max_padding = PAGE_SIZE; 82 static unsigned int min_memreg = RPCRDMA_BOUNCEBUFFERS; 83 static unsigned int max_memreg = RPCRDMA_LAST - 1; 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 = &xprt_rdma_inline_write_padding, 118 .maxlen = sizeof(unsigned int), 119 .mode = 0644, 120 .proc_handler = proc_dointvec_minmax, 121 .extra1 = &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 void 225 rpcrdma_conn_func(struct rpcrdma_ep *ep) 226 { 227 schedule_delayed_work(&ep->rep_connect_worker, 0); 228 } 229 230 void 231 rpcrdma_connect_worker(struct work_struct *work) 232 { 233 struct rpcrdma_ep *ep = 234 container_of(work, struct rpcrdma_ep, rep_connect_worker.work); 235 struct rpcrdma_xprt *r_xprt = 236 container_of(ep, struct rpcrdma_xprt, rx_ep); 237 struct rpc_xprt *xprt = &r_xprt->rx_xprt; 238 239 spin_lock_bh(&xprt->transport_lock); 240 if (++xprt->connect_cookie == 0) /* maintain a reserved value */ 241 ++xprt->connect_cookie; 242 if (ep->rep_connected > 0) { 243 if (!xprt_test_and_set_connected(xprt)) 244 xprt_wake_pending_tasks(xprt, 0); 245 } else { 246 if (xprt_test_and_clear_connected(xprt)) 247 xprt_wake_pending_tasks(xprt, -ENOTCONN); 248 } 249 spin_unlock_bh(&xprt->transport_lock); 250 } 251 252 static void 253 xprt_rdma_connect_worker(struct work_struct *work) 254 { 255 struct rpcrdma_xprt *r_xprt = container_of(work, struct rpcrdma_xprt, 256 rx_connect_worker.work); 257 struct rpc_xprt *xprt = &r_xprt->rx_xprt; 258 int rc = 0; 259 260 xprt_clear_connected(xprt); 261 262 dprintk("RPC: %s: %sconnect\n", __func__, 263 r_xprt->rx_ep.rep_connected != 0 ? "re" : ""); 264 rc = rpcrdma_ep_connect(&r_xprt->rx_ep, &r_xprt->rx_ia); 265 if (rc) 266 xprt_wake_pending_tasks(xprt, rc); 267 268 dprintk("RPC: %s: exit\n", __func__); 269 xprt_clear_connecting(xprt); 270 } 271 272 static void 273 xprt_rdma_inject_disconnect(struct rpc_xprt *xprt) 274 { 275 struct rpcrdma_xprt *r_xprt = container_of(xprt, struct rpcrdma_xprt, 276 rx_xprt); 277 278 pr_info("rpcrdma: injecting transport disconnect on xprt=%p\n", xprt); 279 rdma_disconnect(r_xprt->rx_ia.ri_id); 280 } 281 282 /* 283 * xprt_rdma_destroy 284 * 285 * Destroy the xprt. 286 * Free all memory associated with the object, including its own. 287 * NOTE: none of the *destroy methods free memory for their top-level 288 * objects, even though they may have allocated it (they do free 289 * private memory). It's up to the caller to handle it. In this 290 * case (RDMA transport), all structure memory is inlined with the 291 * struct rpcrdma_xprt. 292 */ 293 static void 294 xprt_rdma_destroy(struct rpc_xprt *xprt) 295 { 296 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 297 298 dprintk("RPC: %s: called\n", __func__); 299 300 cancel_delayed_work_sync(&r_xprt->rx_connect_worker); 301 302 xprt_clear_connected(xprt); 303 304 rpcrdma_ep_destroy(&r_xprt->rx_ep, &r_xprt->rx_ia); 305 rpcrdma_buffer_destroy(&r_xprt->rx_buf); 306 rpcrdma_ia_close(&r_xprt->rx_ia); 307 308 xprt_rdma_free_addresses(xprt); 309 310 xprt_free(xprt); 311 312 dprintk("RPC: %s: returning\n", __func__); 313 314 module_put(THIS_MODULE); 315 } 316 317 static const struct rpc_timeout xprt_rdma_default_timeout = { 318 .to_initval = 60 * HZ, 319 .to_maxval = 60 * HZ, 320 }; 321 322 /** 323 * xprt_setup_rdma - Set up transport to use RDMA 324 * 325 * @args: rpc transport arguments 326 */ 327 static struct rpc_xprt * 328 xprt_setup_rdma(struct xprt_create *args) 329 { 330 struct rpcrdma_create_data_internal cdata; 331 struct rpc_xprt *xprt; 332 struct rpcrdma_xprt *new_xprt; 333 struct rpcrdma_ep *new_ep; 334 struct sockaddr *sap; 335 int rc; 336 337 if (args->addrlen > sizeof(xprt->addr)) { 338 dprintk("RPC: %s: address too large\n", __func__); 339 return ERR_PTR(-EBADF); 340 } 341 342 xprt = xprt_alloc(args->net, sizeof(struct rpcrdma_xprt), 343 xprt_rdma_slot_table_entries, 344 xprt_rdma_slot_table_entries); 345 if (xprt == NULL) { 346 dprintk("RPC: %s: couldn't allocate rpcrdma_xprt\n", 347 __func__); 348 return ERR_PTR(-ENOMEM); 349 } 350 351 /* 60 second timeout, no retries */ 352 xprt->timeout = &xprt_rdma_default_timeout; 353 xprt->bind_timeout = RPCRDMA_BIND_TO; 354 xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO; 355 xprt->idle_timeout = RPCRDMA_IDLE_DISC_TO; 356 357 xprt->resvport = 0; /* privileged port not needed */ 358 xprt->tsh_size = 0; /* RPC-RDMA handles framing */ 359 xprt->ops = &xprt_rdma_procs; 360 361 /* 362 * Set up RDMA-specific connect data. 363 */ 364 365 sap = (struct sockaddr *)&cdata.addr; 366 memcpy(sap, args->dstaddr, args->addrlen); 367 368 /* Ensure xprt->addr holds valid server TCP (not RDMA) 369 * address, for any side protocols which peek at it */ 370 xprt->prot = IPPROTO_TCP; 371 xprt->addrlen = args->addrlen; 372 memcpy(&xprt->addr, sap, xprt->addrlen); 373 374 if (rpc_get_port(sap)) 375 xprt_set_bound(xprt); 376 377 cdata.max_requests = xprt->max_reqs; 378 379 cdata.rsize = RPCRDMA_MAX_SEGS * PAGE_SIZE; /* RDMA write max */ 380 cdata.wsize = RPCRDMA_MAX_SEGS * PAGE_SIZE; /* RDMA read max */ 381 382 cdata.inline_wsize = xprt_rdma_max_inline_write; 383 if (cdata.inline_wsize > cdata.wsize) 384 cdata.inline_wsize = cdata.wsize; 385 386 cdata.inline_rsize = xprt_rdma_max_inline_read; 387 if (cdata.inline_rsize > cdata.rsize) 388 cdata.inline_rsize = cdata.rsize; 389 390 cdata.padding = xprt_rdma_inline_write_padding; 391 392 /* 393 * Create new transport instance, which includes initialized 394 * o ia 395 * o endpoint 396 * o buffers 397 */ 398 399 new_xprt = rpcx_to_rdmax(xprt); 400 401 rc = rpcrdma_ia_open(new_xprt, sap); 402 if (rc) 403 goto out1; 404 405 /* 406 * initialize and create ep 407 */ 408 new_xprt->rx_data = cdata; 409 new_ep = &new_xprt->rx_ep; 410 new_ep->rep_remote_addr = cdata.addr; 411 412 rc = rpcrdma_ep_create(&new_xprt->rx_ep, 413 &new_xprt->rx_ia, &new_xprt->rx_data); 414 if (rc) 415 goto out2; 416 417 /* 418 * Allocate pre-registered send and receive buffers for headers and 419 * any inline data. Also specify any padding which will be provided 420 * from a preregistered zero buffer. 421 */ 422 rc = rpcrdma_buffer_create(new_xprt); 423 if (rc) 424 goto out3; 425 426 /* 427 * Register a callback for connection events. This is necessary because 428 * connection loss notification is async. We also catch connection loss 429 * when reaping receives. 430 */ 431 INIT_DELAYED_WORK(&new_xprt->rx_connect_worker, 432 xprt_rdma_connect_worker); 433 434 xprt_rdma_format_addresses(xprt, sap); 435 xprt->max_payload = new_xprt->rx_ia.ri_ops->ro_maxpages(new_xprt); 436 if (xprt->max_payload == 0) 437 goto out4; 438 xprt->max_payload <<= PAGE_SHIFT; 439 dprintk("RPC: %s: transport data payload maximum: %zu bytes\n", 440 __func__, xprt->max_payload); 441 442 if (!try_module_get(THIS_MODULE)) 443 goto out4; 444 445 dprintk("RPC: %s: %s:%s\n", __func__, 446 xprt->address_strings[RPC_DISPLAY_ADDR], 447 xprt->address_strings[RPC_DISPLAY_PORT]); 448 return xprt; 449 450 out4: 451 xprt_rdma_free_addresses(xprt); 452 rc = -EINVAL; 453 out3: 454 rpcrdma_ep_destroy(new_ep, &new_xprt->rx_ia); 455 out2: 456 rpcrdma_ia_close(&new_xprt->rx_ia); 457 out1: 458 xprt_free(xprt); 459 return ERR_PTR(rc); 460 } 461 462 /** 463 * xprt_rdma_close - Close down RDMA connection 464 * @xprt: generic transport to be closed 465 * 466 * Called during transport shutdown reconnect, or device 467 * removal. Caller holds the transport's write lock. 468 */ 469 static void 470 xprt_rdma_close(struct rpc_xprt *xprt) 471 { 472 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 473 struct rpcrdma_ep *ep = &r_xprt->rx_ep; 474 struct rpcrdma_ia *ia = &r_xprt->rx_ia; 475 476 dprintk("RPC: %s: closing xprt %p\n", __func__, xprt); 477 478 if (test_and_clear_bit(RPCRDMA_IAF_REMOVING, &ia->ri_flags)) { 479 xprt_clear_connected(xprt); 480 rpcrdma_ia_remove(ia); 481 return; 482 } 483 if (ep->rep_connected == -ENODEV) 484 return; 485 if (ep->rep_connected > 0) 486 xprt->reestablish_timeout = 0; 487 xprt_disconnect_done(xprt); 488 rpcrdma_ep_disconnect(ep, ia); 489 } 490 491 static void 492 xprt_rdma_set_port(struct rpc_xprt *xprt, u16 port) 493 { 494 struct sockaddr_in *sap; 495 496 sap = (struct sockaddr_in *)&xprt->addr; 497 sap->sin_port = htons(port); 498 sap = (struct sockaddr_in *)&rpcx_to_rdmad(xprt).addr; 499 sap->sin_port = htons(port); 500 dprintk("RPC: %s: %u\n", __func__, port); 501 } 502 503 /** 504 * xprt_rdma_timer - invoked when an RPC times out 505 * @xprt: controlling RPC transport 506 * @task: RPC task that timed out 507 * 508 * Invoked when the transport is still connected, but an RPC 509 * retransmit timeout occurs. 510 * 511 * Since RDMA connections don't have a keep-alive, forcibly 512 * disconnect and retry to connect. This drives full 513 * detection of the network path, and retransmissions of 514 * all pending RPCs. 515 */ 516 static void 517 xprt_rdma_timer(struct rpc_xprt *xprt, struct rpc_task *task) 518 { 519 dprintk("RPC: %5u %s: xprt = %p\n", task->tk_pid, __func__, xprt); 520 521 xprt_force_disconnect(xprt); 522 } 523 524 static void 525 xprt_rdma_connect(struct rpc_xprt *xprt, struct rpc_task *task) 526 { 527 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 528 529 if (r_xprt->rx_ep.rep_connected != 0) { 530 /* Reconnect */ 531 schedule_delayed_work(&r_xprt->rx_connect_worker, 532 xprt->reestablish_timeout); 533 xprt->reestablish_timeout <<= 1; 534 if (xprt->reestablish_timeout > RPCRDMA_MAX_REEST_TO) 535 xprt->reestablish_timeout = RPCRDMA_MAX_REEST_TO; 536 else if (xprt->reestablish_timeout < RPCRDMA_INIT_REEST_TO) 537 xprt->reestablish_timeout = RPCRDMA_INIT_REEST_TO; 538 } else { 539 schedule_delayed_work(&r_xprt->rx_connect_worker, 0); 540 if (!RPC_IS_ASYNC(task)) 541 flush_delayed_work(&r_xprt->rx_connect_worker); 542 } 543 } 544 545 /* Allocate a fixed-size buffer in which to construct and send the 546 * RPC-over-RDMA header for this request. 547 */ 548 static bool 549 rpcrdma_get_rdmabuf(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, 550 gfp_t flags) 551 { 552 size_t size = RPCRDMA_HDRBUF_SIZE; 553 struct rpcrdma_regbuf *rb; 554 555 if (req->rl_rdmabuf) 556 return true; 557 558 rb = rpcrdma_alloc_regbuf(size, DMA_TO_DEVICE, flags); 559 if (IS_ERR(rb)) 560 return false; 561 562 r_xprt->rx_stats.hardway_register_count += size; 563 req->rl_rdmabuf = rb; 564 xdr_buf_init(&req->rl_hdrbuf, rb->rg_base, rdmab_length(rb)); 565 return true; 566 } 567 568 static bool 569 rpcrdma_get_sendbuf(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, 570 size_t size, gfp_t flags) 571 { 572 struct rpcrdma_regbuf *rb; 573 574 if (req->rl_sendbuf && rdmab_length(req->rl_sendbuf) >= size) 575 return true; 576 577 rb = rpcrdma_alloc_regbuf(size, DMA_TO_DEVICE, flags); 578 if (IS_ERR(rb)) 579 return false; 580 581 rpcrdma_free_regbuf(req->rl_sendbuf); 582 r_xprt->rx_stats.hardway_register_count += size; 583 req->rl_sendbuf = rb; 584 return true; 585 } 586 587 /* The rq_rcv_buf is used only if a Reply chunk is necessary. 588 * The decision to use a Reply chunk is made later in 589 * rpcrdma_marshal_req. This buffer is registered at that time. 590 * 591 * Otherwise, the associated RPC Reply arrives in a separate 592 * Receive buffer, arbitrarily chosen by the HCA. The buffer 593 * allocated here for the RPC Reply is not utilized in that 594 * case. See rpcrdma_inline_fixup. 595 * 596 * A regbuf is used here to remember the buffer size. 597 */ 598 static bool 599 rpcrdma_get_recvbuf(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, 600 size_t size, gfp_t flags) 601 { 602 struct rpcrdma_regbuf *rb; 603 604 if (req->rl_recvbuf && rdmab_length(req->rl_recvbuf) >= size) 605 return true; 606 607 rb = rpcrdma_alloc_regbuf(size, DMA_NONE, flags); 608 if (IS_ERR(rb)) 609 return false; 610 611 rpcrdma_free_regbuf(req->rl_recvbuf); 612 r_xprt->rx_stats.hardway_register_count += size; 613 req->rl_recvbuf = rb; 614 return true; 615 } 616 617 /** 618 * xprt_rdma_allocate - allocate transport resources for an RPC 619 * @task: RPC task 620 * 621 * Return values: 622 * 0: Success; rq_buffer points to RPC buffer to use 623 * ENOMEM: Out of memory, call again later 624 * EIO: A permanent error occurred, do not retry 625 * 626 * The RDMA allocate/free functions need the task structure as a place 627 * to hide the struct rpcrdma_req, which is necessary for the actual 628 * send/recv sequence. 629 * 630 * xprt_rdma_allocate provides buffers that are already mapped for 631 * DMA, and a local DMA lkey is provided for each. 632 */ 633 static int 634 xprt_rdma_allocate(struct rpc_task *task) 635 { 636 struct rpc_rqst *rqst = task->tk_rqstp; 637 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); 638 struct rpcrdma_req *req; 639 gfp_t flags; 640 641 req = rpcrdma_buffer_get(&r_xprt->rx_buf); 642 if (req == NULL) 643 return -ENOMEM; 644 645 flags = RPCRDMA_DEF_GFP; 646 if (RPC_IS_SWAPPER(task)) 647 flags = __GFP_MEMALLOC | GFP_NOWAIT | __GFP_NOWARN; 648 649 if (!rpcrdma_get_rdmabuf(r_xprt, req, flags)) 650 goto out_fail; 651 if (!rpcrdma_get_sendbuf(r_xprt, req, rqst->rq_callsize, flags)) 652 goto out_fail; 653 if (!rpcrdma_get_recvbuf(r_xprt, req, rqst->rq_rcvsize, flags)) 654 goto out_fail; 655 656 dprintk("RPC: %5u %s: send size = %zd, recv size = %zd, req = %p\n", 657 task->tk_pid, __func__, rqst->rq_callsize, 658 rqst->rq_rcvsize, req); 659 660 req->rl_cpu = smp_processor_id(); 661 req->rl_connect_cookie = 0; /* our reserved value */ 662 rpcrdma_set_xprtdata(rqst, req); 663 rqst->rq_buffer = req->rl_sendbuf->rg_base; 664 rqst->rq_rbuffer = req->rl_recvbuf->rg_base; 665 return 0; 666 667 out_fail: 668 rpcrdma_buffer_put(req); 669 return -ENOMEM; 670 } 671 672 /** 673 * xprt_rdma_free - release resources allocated by xprt_rdma_allocate 674 * @task: RPC task 675 * 676 * Caller guarantees rqst->rq_buffer is non-NULL. 677 */ 678 static void 679 xprt_rdma_free(struct rpc_task *task) 680 { 681 struct rpc_rqst *rqst = task->tk_rqstp; 682 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); 683 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 684 685 if (test_bit(RPCRDMA_REQ_F_BACKCHANNEL, &req->rl_flags)) 686 return; 687 688 dprintk("RPC: %s: called on 0x%p\n", __func__, req->rl_reply); 689 690 if (test_bit(RPCRDMA_REQ_F_PENDING, &req->rl_flags)) 691 rpcrdma_release_rqst(r_xprt, req); 692 rpcrdma_buffer_put(req); 693 } 694 695 /** 696 * xprt_rdma_send_request - marshal and send an RPC request 697 * @task: RPC task with an RPC message in rq_snd_buf 698 * 699 * Caller holds the transport's write lock. 700 * 701 * Return values: 702 * 0: The request has been sent 703 * ENOTCONN: Caller needs to invoke connect logic then call again 704 * ENOBUFS: Call again later to send the request 705 * EIO: A permanent error occurred. The request was not sent, 706 * and don't try it again 707 * 708 * send_request invokes the meat of RPC RDMA. It must do the following: 709 * 710 * 1. Marshal the RPC request into an RPC RDMA request, which means 711 * putting a header in front of data, and creating IOVs for RDMA 712 * from those in the request. 713 * 2. In marshaling, detect opportunities for RDMA, and use them. 714 * 3. Post a recv message to set up asynch completion, then send 715 * the request (rpcrdma_ep_post). 716 * 4. No partial sends are possible in the RPC-RDMA protocol (as in UDP). 717 */ 718 static int 719 xprt_rdma_send_request(struct rpc_task *task) 720 { 721 struct rpc_rqst *rqst = task->tk_rqstp; 722 struct rpc_xprt *xprt = rqst->rq_xprt; 723 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 724 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 725 int rc = 0; 726 727 if (!xprt_connected(xprt)) 728 goto drop_connection; 729 730 /* On retransmit, remove any previously registered chunks */ 731 if (unlikely(!list_empty(&req->rl_registered))) 732 r_xprt->rx_ia.ri_ops->ro_unmap_sync(r_xprt, 733 &req->rl_registered); 734 735 rc = rpcrdma_marshal_req(r_xprt, rqst); 736 if (rc < 0) 737 goto failed_marshal; 738 739 if (req->rl_reply == NULL) /* e.g. reconnection */ 740 rpcrdma_recv_buffer_get(req); 741 742 /* Must suppress retransmit to maintain credits */ 743 if (req->rl_connect_cookie == xprt->connect_cookie) 744 goto drop_connection; 745 req->rl_connect_cookie = xprt->connect_cookie; 746 747 set_bit(RPCRDMA_REQ_F_PENDING, &req->rl_flags); 748 if (rpcrdma_ep_post(&r_xprt->rx_ia, &r_xprt->rx_ep, req)) 749 goto drop_connection; 750 751 rqst->rq_xmit_bytes_sent += rqst->rq_snd_buf.len; 752 rqst->rq_bytes_sent = 0; 753 return 0; 754 755 failed_marshal: 756 if (rc != -ENOTCONN) 757 return rc; 758 drop_connection: 759 xprt_disconnect_done(xprt); 760 return -ENOTCONN; /* implies disconnect */ 761 } 762 763 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) 764 { 765 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 766 long idle_time = 0; 767 768 if (xprt_connected(xprt)) 769 idle_time = (long)(jiffies - xprt->last_used) / HZ; 770 771 seq_puts(seq, "\txprt:\trdma "); 772 seq_printf(seq, "%u %lu %lu %lu %ld %lu %lu %lu %llu %llu ", 773 0, /* need a local port? */ 774 xprt->stat.bind_count, 775 xprt->stat.connect_count, 776 xprt->stat.connect_time, 777 idle_time, 778 xprt->stat.sends, 779 xprt->stat.recvs, 780 xprt->stat.bad_xids, 781 xprt->stat.req_u, 782 xprt->stat.bklog_u); 783 seq_printf(seq, "%lu %lu %lu %llu %llu %llu %llu %lu %lu %lu %lu ", 784 r_xprt->rx_stats.read_chunk_count, 785 r_xprt->rx_stats.write_chunk_count, 786 r_xprt->rx_stats.reply_chunk_count, 787 r_xprt->rx_stats.total_rdma_request, 788 r_xprt->rx_stats.total_rdma_reply, 789 r_xprt->rx_stats.pullup_copy_count, 790 r_xprt->rx_stats.fixup_copy_count, 791 r_xprt->rx_stats.hardway_register_count, 792 r_xprt->rx_stats.failed_marshal_count, 793 r_xprt->rx_stats.bad_reply_count, 794 r_xprt->rx_stats.nomsg_call_count); 795 seq_printf(seq, "%lu %lu %lu %lu %lu %lu\n", 796 r_xprt->rx_stats.mrs_recovered, 797 r_xprt->rx_stats.mrs_orphaned, 798 r_xprt->rx_stats.mrs_allocated, 799 r_xprt->rx_stats.local_inv_needed, 800 r_xprt->rx_stats.empty_sendctx_q, 801 r_xprt->rx_stats.reply_waits_for_send); 802 } 803 804 static int 805 xprt_rdma_enable_swap(struct rpc_xprt *xprt) 806 { 807 return 0; 808 } 809 810 static void 811 xprt_rdma_disable_swap(struct rpc_xprt *xprt) 812 { 813 } 814 815 /* 816 * Plumbing for rpc transport switch and kernel module 817 */ 818 819 static const struct rpc_xprt_ops xprt_rdma_procs = { 820 .reserve_xprt = xprt_reserve_xprt_cong, 821 .release_xprt = xprt_release_xprt_cong, /* sunrpc/xprt.c */ 822 .alloc_slot = xprt_alloc_slot, 823 .release_request = xprt_release_rqst_cong, /* ditto */ 824 .set_retrans_timeout = xprt_set_retrans_timeout_def, /* ditto */ 825 .timer = xprt_rdma_timer, 826 .rpcbind = rpcb_getport_async, /* sunrpc/rpcb_clnt.c */ 827 .set_port = xprt_rdma_set_port, 828 .connect = xprt_rdma_connect, 829 .buf_alloc = xprt_rdma_allocate, 830 .buf_free = xprt_rdma_free, 831 .send_request = xprt_rdma_send_request, 832 .close = xprt_rdma_close, 833 .destroy = xprt_rdma_destroy, 834 .print_stats = xprt_rdma_print_stats, 835 .enable_swap = xprt_rdma_enable_swap, 836 .disable_swap = xprt_rdma_disable_swap, 837 .inject_disconnect = xprt_rdma_inject_disconnect, 838 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 839 .bc_setup = xprt_rdma_bc_setup, 840 .bc_up = xprt_rdma_bc_up, 841 .bc_maxpayload = xprt_rdma_bc_maxpayload, 842 .bc_free_rqst = xprt_rdma_bc_free_rqst, 843 .bc_destroy = xprt_rdma_bc_destroy, 844 #endif 845 }; 846 847 static struct xprt_class xprt_rdma = { 848 .list = LIST_HEAD_INIT(xprt_rdma.list), 849 .name = "rdma", 850 .owner = THIS_MODULE, 851 .ident = XPRT_TRANSPORT_RDMA, 852 .setup = xprt_setup_rdma, 853 }; 854 855 void xprt_rdma_cleanup(void) 856 { 857 int rc; 858 859 dprintk("RPCRDMA Module Removed, deregister RPC RDMA transport\n"); 860 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 861 if (sunrpc_table_header) { 862 unregister_sysctl_table(sunrpc_table_header); 863 sunrpc_table_header = NULL; 864 } 865 #endif 866 rc = xprt_unregister_transport(&xprt_rdma); 867 if (rc) 868 dprintk("RPC: %s: xprt_unregister returned %i\n", 869 __func__, rc); 870 871 rpcrdma_destroy_wq(); 872 873 rc = xprt_unregister_transport(&xprt_rdma_bc); 874 if (rc) 875 dprintk("RPC: %s: xprt_unregister(bc) returned %i\n", 876 __func__, rc); 877 } 878 879 int xprt_rdma_init(void) 880 { 881 int rc; 882 883 rc = rpcrdma_alloc_wq(); 884 if (rc) 885 return rc; 886 887 rc = xprt_register_transport(&xprt_rdma); 888 if (rc) { 889 rpcrdma_destroy_wq(); 890 return rc; 891 } 892 893 rc = xprt_register_transport(&xprt_rdma_bc); 894 if (rc) { 895 xprt_unregister_transport(&xprt_rdma); 896 rpcrdma_destroy_wq(); 897 return rc; 898 } 899 900 dprintk("RPCRDMA Module Init, register RPC RDMA transport\n"); 901 902 dprintk("Defaults:\n"); 903 dprintk("\tSlots %d\n" 904 "\tMaxInlineRead %d\n\tMaxInlineWrite %d\n", 905 xprt_rdma_slot_table_entries, 906 xprt_rdma_max_inline_read, xprt_rdma_max_inline_write); 907 dprintk("\tPadding %d\n\tMemreg %d\n", 908 xprt_rdma_inline_write_padding, xprt_rdma_memreg_strategy); 909 910 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 911 if (!sunrpc_table_header) 912 sunrpc_table_header = register_sysctl_table(sunrpc_table); 913 #endif 914 return 0; 915 } 916