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 #ifndef _LINUX_SUNRPC_XPRT_RDMA_H 43 #define _LINUX_SUNRPC_XPRT_RDMA_H 44 45 #include <linux/wait.h> /* wait_queue_head_t, etc */ 46 #include <linux/spinlock.h> /* spinlock_t, etc */ 47 #include <linux/atomic.h> /* atomic_t, etc */ 48 #include <linux/kref.h> /* struct kref */ 49 #include <linux/workqueue.h> /* struct work_struct */ 50 #include <linux/llist.h> 51 52 #include <rdma/rdma_cm.h> /* RDMA connection api */ 53 #include <rdma/ib_verbs.h> /* RDMA verbs api */ 54 55 #include <linux/sunrpc/clnt.h> /* rpc_xprt */ 56 #include <linux/sunrpc/rpc_rdma.h> /* RPC/RDMA protocol */ 57 #include <linux/sunrpc/xprtrdma.h> /* xprt parameters */ 58 59 #define RDMA_RESOLVE_TIMEOUT (5000) /* 5 seconds */ 60 #define RDMA_CONNECT_RETRY_MAX (2) /* retries if no listener backlog */ 61 62 #define RPCRDMA_BIND_TO (60U * HZ) 63 #define RPCRDMA_INIT_REEST_TO (5U * HZ) 64 #define RPCRDMA_MAX_REEST_TO (30U * HZ) 65 #define RPCRDMA_IDLE_DISC_TO (5U * 60 * HZ) 66 67 /* 68 * Interface Adapter -- one per transport instance 69 */ 70 struct rpcrdma_ia { 71 struct rdma_cm_id *ri_id; 72 struct ib_pd *ri_pd; 73 int ri_async_rc; 74 unsigned int ri_max_segs; 75 unsigned int ri_max_frwr_depth; 76 unsigned int ri_max_send_sges; 77 bool ri_implicit_roundup; 78 enum ib_mr_type ri_mrtype; 79 unsigned long ri_flags; 80 struct completion ri_done; 81 struct completion ri_remove_done; 82 }; 83 84 enum { 85 RPCRDMA_IAF_REMOVING = 0, 86 }; 87 88 /* 89 * RDMA Endpoint -- one per transport instance 90 */ 91 92 struct rpcrdma_ep { 93 unsigned int rep_send_count; 94 unsigned int rep_send_batch; 95 unsigned int rep_max_inline_send; 96 unsigned int rep_max_inline_recv; 97 int rep_connected; 98 struct ib_qp_init_attr rep_attr; 99 wait_queue_head_t rep_connect_wait; 100 struct rpcrdma_connect_private rep_cm_private; 101 struct rdma_conn_param rep_remote_cma; 102 unsigned int rep_max_requests; /* set by /proc */ 103 unsigned int rep_inline_send; /* negotiated */ 104 unsigned int rep_inline_recv; /* negotiated */ 105 int rep_receive_count; 106 }; 107 108 /* Pre-allocate extra Work Requests for handling backward receives 109 * and sends. This is a fixed value because the Work Queues are 110 * allocated when the forward channel is set up, long before the 111 * backchannel is provisioned. This value is two times 112 * NFS4_DEF_CB_SLOT_TABLE_SIZE. 113 */ 114 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 115 #define RPCRDMA_BACKWARD_WRS (32) 116 #else 117 #define RPCRDMA_BACKWARD_WRS (0) 118 #endif 119 120 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV 121 */ 122 123 struct rpcrdma_regbuf { 124 struct ib_sge rg_iov; 125 struct ib_device *rg_device; 126 enum dma_data_direction rg_direction; 127 void *rg_data; 128 }; 129 130 static inline u64 rdmab_addr(struct rpcrdma_regbuf *rb) 131 { 132 return rb->rg_iov.addr; 133 } 134 135 static inline u32 rdmab_length(struct rpcrdma_regbuf *rb) 136 { 137 return rb->rg_iov.length; 138 } 139 140 static inline u32 rdmab_lkey(struct rpcrdma_regbuf *rb) 141 { 142 return rb->rg_iov.lkey; 143 } 144 145 static inline struct ib_device *rdmab_device(struct rpcrdma_regbuf *rb) 146 { 147 return rb->rg_device; 148 } 149 150 static inline void *rdmab_data(const struct rpcrdma_regbuf *rb) 151 { 152 return rb->rg_data; 153 } 154 155 #define RPCRDMA_DEF_GFP (GFP_NOIO | __GFP_NOWARN) 156 157 /* To ensure a transport can always make forward progress, 158 * the number of RDMA segments allowed in header chunk lists 159 * is capped at 16. This prevents less-capable devices from 160 * overrunning the Send buffer while building chunk lists. 161 * 162 * Elements of the Read list take up more room than the 163 * Write list or Reply chunk. 16 read segments means the 164 * chunk lists cannot consume more than 165 * 166 * ((16 + 2) * read segment size) + 1 XDR words, 167 * 168 * or about 400 bytes. The fixed part of the header is 169 * another 24 bytes. Thus when the inline threshold is 170 * 1024 bytes, at least 600 bytes are available for RPC 171 * message bodies. 172 */ 173 enum { 174 RPCRDMA_MAX_HDR_SEGS = 16, 175 }; 176 177 /* 178 * struct rpcrdma_rep -- this structure encapsulates state required 179 * to receive and complete an RPC Reply, asychronously. It needs 180 * several pieces of state: 181 * 182 * o receive buffer and ib_sge (donated to provider) 183 * o status of receive (success or not, length, inv rkey) 184 * o bookkeeping state to get run by reply handler (XDR stream) 185 * 186 * These structures are allocated during transport initialization. 187 * N of these are associated with a transport instance, managed by 188 * struct rpcrdma_buffer. N is the max number of outstanding RPCs. 189 */ 190 191 struct rpcrdma_rep { 192 struct ib_cqe rr_cqe; 193 __be32 rr_xid; 194 __be32 rr_vers; 195 __be32 rr_proc; 196 int rr_wc_flags; 197 u32 rr_inv_rkey; 198 bool rr_temp; 199 struct rpcrdma_regbuf *rr_rdmabuf; 200 struct rpcrdma_xprt *rr_rxprt; 201 struct rpc_rqst *rr_rqst; 202 struct xdr_buf rr_hdrbuf; 203 struct xdr_stream rr_stream; 204 struct llist_node rr_node; 205 struct ib_recv_wr rr_recv_wr; 206 }; 207 208 /* To reduce the rate at which a transport invokes ib_post_recv 209 * (and thus the hardware doorbell rate), xprtrdma posts Receive 210 * WRs in batches. 211 * 212 * Setting this to zero disables Receive post batching. 213 */ 214 enum { 215 RPCRDMA_MAX_RECV_BATCH = 7, 216 }; 217 218 /* struct rpcrdma_sendctx - DMA mapped SGEs to unmap after Send completes 219 */ 220 struct rpcrdma_req; 221 struct rpcrdma_sendctx { 222 struct ib_cqe sc_cqe; 223 struct rpcrdma_req *sc_req; 224 unsigned int sc_unmap_count; 225 struct ib_sge sc_sges[]; 226 }; 227 228 /* 229 * struct rpcrdma_mr - external memory region metadata 230 * 231 * An external memory region is any buffer or page that is registered 232 * on the fly (ie, not pre-registered). 233 */ 234 struct rpcrdma_frwr { 235 struct ib_mr *fr_mr; 236 struct ib_cqe fr_cqe; 237 struct completion fr_linv_done; 238 union { 239 struct ib_reg_wr fr_regwr; 240 struct ib_send_wr fr_invwr; 241 }; 242 }; 243 244 struct rpcrdma_req; 245 struct rpcrdma_mr { 246 struct list_head mr_list; 247 struct rpcrdma_req *mr_req; 248 struct scatterlist *mr_sg; 249 int mr_nents; 250 enum dma_data_direction mr_dir; 251 struct rpcrdma_frwr frwr; 252 struct rpcrdma_xprt *mr_xprt; 253 u32 mr_handle; 254 u32 mr_length; 255 u64 mr_offset; 256 struct list_head mr_all; 257 }; 258 259 /* 260 * struct rpcrdma_req -- structure central to the request/reply sequence. 261 * 262 * N of these are associated with a transport instance, and stored in 263 * struct rpcrdma_buffer. N is the max number of outstanding requests. 264 * 265 * It includes pre-registered buffer memory for send AND recv. 266 * The recv buffer, however, is not owned by this structure, and 267 * is "donated" to the hardware when a recv is posted. When a 268 * reply is handled, the recv buffer used is given back to the 269 * struct rpcrdma_req associated with the request. 270 * 271 * In addition to the basic memory, this structure includes an array 272 * of iovs for send operations. The reason is that the iovs passed to 273 * ib_post_{send,recv} must not be modified until the work request 274 * completes. 275 */ 276 277 /* Maximum number of page-sized "segments" per chunk list to be 278 * registered or invalidated. Must handle a Reply chunk: 279 */ 280 enum { 281 RPCRDMA_MAX_IOV_SEGS = 3, 282 RPCRDMA_MAX_DATA_SEGS = ((1 * 1024 * 1024) / PAGE_SIZE) + 1, 283 RPCRDMA_MAX_SEGS = RPCRDMA_MAX_DATA_SEGS + 284 RPCRDMA_MAX_IOV_SEGS, 285 }; 286 287 struct rpcrdma_mr_seg { /* chunk descriptors */ 288 u32 mr_len; /* length of chunk or segment */ 289 struct page *mr_page; /* owning page, if any */ 290 char *mr_offset; /* kva if no page, else offset */ 291 }; 292 293 /* The Send SGE array is provisioned to send a maximum size 294 * inline request: 295 * - RPC-over-RDMA header 296 * - xdr_buf head iovec 297 * - RPCRDMA_MAX_INLINE bytes, in pages 298 * - xdr_buf tail iovec 299 * 300 * The actual number of array elements consumed by each RPC 301 * depends on the device's max_sge limit. 302 */ 303 enum { 304 RPCRDMA_MIN_SEND_SGES = 3, 305 RPCRDMA_MAX_PAGE_SGES = RPCRDMA_MAX_INLINE >> PAGE_SHIFT, 306 RPCRDMA_MAX_SEND_SGES = 1 + 1 + RPCRDMA_MAX_PAGE_SGES + 1, 307 }; 308 309 struct rpcrdma_buffer; 310 struct rpcrdma_req { 311 struct list_head rl_list; 312 struct rpc_rqst rl_slot; 313 struct rpcrdma_rep *rl_reply; 314 struct xdr_stream rl_stream; 315 struct xdr_buf rl_hdrbuf; 316 struct ib_send_wr rl_wr; 317 struct rpcrdma_sendctx *rl_sendctx; 318 struct rpcrdma_regbuf *rl_rdmabuf; /* xprt header */ 319 struct rpcrdma_regbuf *rl_sendbuf; /* rq_snd_buf */ 320 struct rpcrdma_regbuf *rl_recvbuf; /* rq_rcv_buf */ 321 322 struct list_head rl_all; 323 struct kref rl_kref; 324 325 struct list_head rl_free_mrs; 326 struct list_head rl_registered; 327 struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; 328 }; 329 330 static inline struct rpcrdma_req * 331 rpcr_to_rdmar(const struct rpc_rqst *rqst) 332 { 333 return container_of(rqst, struct rpcrdma_req, rl_slot); 334 } 335 336 static inline void 337 rpcrdma_mr_push(struct rpcrdma_mr *mr, struct list_head *list) 338 { 339 list_add(&mr->mr_list, list); 340 } 341 342 static inline struct rpcrdma_mr * 343 rpcrdma_mr_pop(struct list_head *list) 344 { 345 struct rpcrdma_mr *mr; 346 347 mr = list_first_entry_or_null(list, struct rpcrdma_mr, mr_list); 348 if (mr) 349 list_del_init(&mr->mr_list); 350 return mr; 351 } 352 353 /* 354 * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for 355 * inline requests/replies, and client/server credits. 356 * 357 * One of these is associated with a transport instance 358 */ 359 struct rpcrdma_buffer { 360 spinlock_t rb_lock; 361 struct list_head rb_send_bufs; 362 struct list_head rb_mrs; 363 364 unsigned long rb_sc_head; 365 unsigned long rb_sc_tail; 366 unsigned long rb_sc_last; 367 struct rpcrdma_sendctx **rb_sc_ctxs; 368 369 struct list_head rb_allreqs; 370 struct list_head rb_all_mrs; 371 372 struct llist_head rb_free_reps; 373 374 u32 rb_max_requests; 375 u32 rb_credits; /* most recent credit grant */ 376 377 u32 rb_bc_srv_max_requests; 378 u32 rb_bc_max_requests; 379 380 struct work_struct rb_refresh_worker; 381 }; 382 383 /* 384 * Statistics for RPCRDMA 385 */ 386 struct rpcrdma_stats { 387 /* accessed when sending a call */ 388 unsigned long read_chunk_count; 389 unsigned long write_chunk_count; 390 unsigned long reply_chunk_count; 391 unsigned long long total_rdma_request; 392 393 /* rarely accessed error counters */ 394 unsigned long long pullup_copy_count; 395 unsigned long hardway_register_count; 396 unsigned long failed_marshal_count; 397 unsigned long bad_reply_count; 398 unsigned long mrs_recycled; 399 unsigned long mrs_orphaned; 400 unsigned long mrs_allocated; 401 unsigned long empty_sendctx_q; 402 403 /* accessed when receiving a reply */ 404 unsigned long long total_rdma_reply; 405 unsigned long long fixup_copy_count; 406 unsigned long reply_waits_for_send; 407 unsigned long local_inv_needed; 408 unsigned long nomsg_call_count; 409 unsigned long bcall_count; 410 }; 411 412 /* 413 * RPCRDMA transport -- encapsulates the structures above for 414 * integration with RPC. 415 * 416 * The contained structures are embedded, not pointers, 417 * for convenience. This structure need not be visible externally. 418 * 419 * It is allocated and initialized during mount, and released 420 * during unmount. 421 */ 422 struct rpcrdma_xprt { 423 struct rpc_xprt rx_xprt; 424 struct rpcrdma_ia rx_ia; 425 struct rpcrdma_ep rx_ep; 426 struct rpcrdma_buffer rx_buf; 427 struct delayed_work rx_connect_worker; 428 struct rpc_timeout rx_timeout; 429 struct rpcrdma_stats rx_stats; 430 }; 431 432 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt) 433 434 static inline const char * 435 rpcrdma_addrstr(const struct rpcrdma_xprt *r_xprt) 436 { 437 return r_xprt->rx_xprt.address_strings[RPC_DISPLAY_ADDR]; 438 } 439 440 static inline const char * 441 rpcrdma_portstr(const struct rpcrdma_xprt *r_xprt) 442 { 443 return r_xprt->rx_xprt.address_strings[RPC_DISPLAY_PORT]; 444 } 445 446 /* Setting this to 0 ensures interoperability with early servers. 447 * Setting this to 1 enhances certain unaligned read/write performance. 448 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */ 449 extern int xprt_rdma_pad_optimize; 450 451 /* This setting controls the hunt for a supported memory 452 * registration strategy. 453 */ 454 extern unsigned int xprt_rdma_memreg_strategy; 455 456 /* 457 * Interface Adapter calls - xprtrdma/verbs.c 458 */ 459 int rpcrdma_ia_open(struct rpcrdma_xprt *xprt); 460 void rpcrdma_ia_remove(struct rpcrdma_ia *ia); 461 void rpcrdma_ia_close(struct rpcrdma_ia *); 462 463 /* 464 * Endpoint calls - xprtrdma/verbs.c 465 */ 466 int rpcrdma_ep_create(struct rpcrdma_xprt *r_xprt); 467 void rpcrdma_ep_destroy(struct rpcrdma_xprt *r_xprt); 468 int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *); 469 void rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *); 470 471 int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, 472 struct rpcrdma_req *); 473 void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp); 474 475 /* 476 * Buffer calls - xprtrdma/verbs.c 477 */ 478 struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt, size_t size, 479 gfp_t flags); 480 void rpcrdma_req_destroy(struct rpcrdma_req *req); 481 int rpcrdma_buffer_create(struct rpcrdma_xprt *); 482 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *); 483 struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt); 484 485 struct rpcrdma_mr *rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt); 486 void rpcrdma_mr_put(struct rpcrdma_mr *mr); 487 void rpcrdma_mrs_refresh(struct rpcrdma_xprt *r_xprt); 488 489 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); 490 void rpcrdma_buffer_put(struct rpcrdma_buffer *buffers, 491 struct rpcrdma_req *req); 492 void rpcrdma_recv_buffer_put(struct rpcrdma_rep *); 493 494 bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size, 495 gfp_t flags); 496 bool __rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt, 497 struct rpcrdma_regbuf *rb); 498 499 /** 500 * rpcrdma_regbuf_is_mapped - check if buffer is DMA mapped 501 * 502 * Returns true if the buffer is now mapped to rb->rg_device. 503 */ 504 static inline bool rpcrdma_regbuf_is_mapped(struct rpcrdma_regbuf *rb) 505 { 506 return rb->rg_device != NULL; 507 } 508 509 /** 510 * rpcrdma_regbuf_dma_map - DMA-map a regbuf 511 * @r_xprt: controlling transport instance 512 * @rb: regbuf to be mapped 513 * 514 * Returns true if the buffer is currently DMA mapped. 515 */ 516 static inline bool rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt, 517 struct rpcrdma_regbuf *rb) 518 { 519 if (likely(rpcrdma_regbuf_is_mapped(rb))) 520 return true; 521 return __rpcrdma_regbuf_dma_map(r_xprt, rb); 522 } 523 524 /* 525 * Wrappers for chunk registration, shared by read/write chunk code. 526 */ 527 528 static inline enum dma_data_direction 529 rpcrdma_data_dir(bool writing) 530 { 531 return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 532 } 533 534 /* Memory registration calls xprtrdma/frwr_ops.c 535 */ 536 bool frwr_is_supported(struct ib_device *device); 537 void frwr_reset(struct rpcrdma_req *req); 538 int frwr_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep); 539 int frwr_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr); 540 void frwr_release_mr(struct rpcrdma_mr *mr); 541 size_t frwr_maxpages(struct rpcrdma_xprt *r_xprt); 542 struct rpcrdma_mr_seg *frwr_map(struct rpcrdma_xprt *r_xprt, 543 struct rpcrdma_mr_seg *seg, 544 int nsegs, bool writing, __be32 xid, 545 struct rpcrdma_mr *mr); 546 int frwr_send(struct rpcrdma_ia *ia, struct rpcrdma_req *req); 547 void frwr_reminv(struct rpcrdma_rep *rep, struct list_head *mrs); 548 void frwr_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req); 549 void frwr_unmap_async(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req); 550 551 /* 552 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c 553 */ 554 555 enum rpcrdma_chunktype { 556 rpcrdma_noch = 0, 557 rpcrdma_noch_pullup, 558 rpcrdma_noch_mapped, 559 rpcrdma_readch, 560 rpcrdma_areadch, 561 rpcrdma_writech, 562 rpcrdma_replych 563 }; 564 565 int rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt, 566 struct rpcrdma_req *req, u32 hdrlen, 567 struct xdr_buf *xdr, 568 enum rpcrdma_chunktype rtype); 569 void rpcrdma_sendctx_unmap(struct rpcrdma_sendctx *sc); 570 int rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst); 571 void rpcrdma_set_max_header_sizes(struct rpcrdma_xprt *); 572 void rpcrdma_reset_cwnd(struct rpcrdma_xprt *r_xprt); 573 void rpcrdma_complete_rqst(struct rpcrdma_rep *rep); 574 void rpcrdma_reply_handler(struct rpcrdma_rep *rep); 575 576 static inline void rpcrdma_set_xdrlen(struct xdr_buf *xdr, size_t len) 577 { 578 xdr->head[0].iov_len = len; 579 xdr->len = len; 580 } 581 582 /* RPC/RDMA module init - xprtrdma/transport.c 583 */ 584 extern unsigned int xprt_rdma_slot_table_entries; 585 extern unsigned int xprt_rdma_max_inline_read; 586 extern unsigned int xprt_rdma_max_inline_write; 587 void xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap); 588 void xprt_rdma_free_addresses(struct rpc_xprt *xprt); 589 void xprt_rdma_close(struct rpc_xprt *xprt); 590 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq); 591 int xprt_rdma_init(void); 592 void xprt_rdma_cleanup(void); 593 594 /* Backchannel calls - xprtrdma/backchannel.c 595 */ 596 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 597 int xprt_rdma_bc_setup(struct rpc_xprt *, unsigned int); 598 size_t xprt_rdma_bc_maxpayload(struct rpc_xprt *); 599 unsigned int xprt_rdma_bc_max_slots(struct rpc_xprt *); 600 int rpcrdma_bc_post_recv(struct rpcrdma_xprt *, unsigned int); 601 void rpcrdma_bc_receive_call(struct rpcrdma_xprt *, struct rpcrdma_rep *); 602 int xprt_rdma_bc_send_reply(struct rpc_rqst *rqst); 603 void xprt_rdma_bc_free_rqst(struct rpc_rqst *); 604 void xprt_rdma_bc_destroy(struct rpc_xprt *, unsigned int); 605 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 606 607 extern struct xprt_class xprt_rdma_bc; 608 609 #endif /* _LINUX_SUNRPC_XPRT_RDMA_H */ 610