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