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