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_mr;
72 struct rpcrdma_ep {
73 	struct kref		re_kref;
74 	struct rdma_cm_id 	*re_id;
75 	struct ib_pd		*re_pd;
76 	unsigned int		re_max_rdma_segs;
77 	unsigned int		re_max_fr_depth;
78 	struct rpcrdma_mr	*re_write_pad_mr;
79 	enum ib_mr_type		re_mrtype;
80 	struct completion	re_done;
81 	unsigned int		re_send_count;
82 	unsigned int		re_send_batch;
83 	unsigned int		re_max_inline_send;
84 	unsigned int		re_max_inline_recv;
85 	int			re_async_rc;
86 	int			re_connect_status;
87 	atomic_t		re_receiving;
88 	atomic_t		re_force_disconnect;
89 	struct ib_qp_init_attr	re_attr;
90 	wait_queue_head_t       re_connect_wait;
91 	struct rpc_xprt		*re_xprt;
92 	struct rpcrdma_connect_private
93 				re_cm_private;
94 	struct rdma_conn_param	re_remote_cma;
95 	int			re_receive_count;
96 	unsigned int		re_max_requests; /* depends on device */
97 	unsigned int		re_inline_send;	/* negotiated */
98 	unsigned int		re_inline_recv;	/* negotiated */
99 
100 	atomic_t		re_completion_ids;
101 
102 	char			re_write_pad[XDR_UNIT];
103 };
104 
105 /* Pre-allocate extra Work Requests for handling reverse-direction
106  * Receives and Sends. This is a fixed value because the Work Queues
107  * are allocated when the forward channel is set up, long before the
108  * backchannel is provisioned. This value is two times
109  * NFS4_DEF_CB_SLOT_TABLE_SIZE.
110  */
111 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
112 #define RPCRDMA_BACKWARD_WRS (32)
113 #else
114 #define RPCRDMA_BACKWARD_WRS (0)
115 #endif
116 
117 /* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV
118  */
119 
120 struct rpcrdma_regbuf {
121 	struct ib_sge		rg_iov;
122 	struct ib_device	*rg_device;
123 	enum dma_data_direction	rg_direction;
124 	void			*rg_data;
125 };
126 
rdmab_addr(struct rpcrdma_regbuf * rb)127 static inline u64 rdmab_addr(struct rpcrdma_regbuf *rb)
128 {
129 	return rb->rg_iov.addr;
130 }
131 
rdmab_length(struct rpcrdma_regbuf * rb)132 static inline u32 rdmab_length(struct rpcrdma_regbuf *rb)
133 {
134 	return rb->rg_iov.length;
135 }
136 
rdmab_lkey(struct rpcrdma_regbuf * rb)137 static inline u32 rdmab_lkey(struct rpcrdma_regbuf *rb)
138 {
139 	return rb->rg_iov.lkey;
140 }
141 
rdmab_device(struct rpcrdma_regbuf * rb)142 static inline struct ib_device *rdmab_device(struct rpcrdma_regbuf *rb)
143 {
144 	return rb->rg_device;
145 }
146 
rdmab_data(const struct rpcrdma_regbuf * rb)147 static inline void *rdmab_data(const struct rpcrdma_regbuf *rb)
148 {
149 	return rb->rg_data;
150 }
151 
152 #define RPCRDMA_DEF_GFP		(GFP_NOIO | __GFP_NOWARN)
153 
154 /* To ensure a transport can always make forward progress,
155  * the number of RDMA segments allowed in header chunk lists
156  * is capped at 16. This prevents less-capable devices from
157  * overrunning the Send buffer while building chunk lists.
158  *
159  * Elements of the Read list take up more room than the
160  * Write list or Reply chunk. 16 read segments means the
161  * chunk lists cannot consume more than
162  *
163  * ((16 + 2) * read segment size) + 1 XDR words,
164  *
165  * or about 400 bytes. The fixed part of the header is
166  * another 24 bytes. Thus when the inline threshold is
167  * 1024 bytes, at least 600 bytes are available for RPC
168  * message bodies.
169  */
170 enum {
171 	RPCRDMA_MAX_HDR_SEGS = 16,
172 };
173 
174 /*
175  * struct rpcrdma_rep -- this structure encapsulates state required
176  * to receive and complete an RPC Reply, asychronously. It needs
177  * several pieces of state:
178  *
179  *   o receive buffer and ib_sge (donated to provider)
180  *   o status of receive (success or not, length, inv rkey)
181  *   o bookkeeping state to get run by reply handler (XDR stream)
182  *
183  * These structures are allocated during transport initialization.
184  * N of these are associated with a transport instance, managed by
185  * struct rpcrdma_buffer. N is the max number of outstanding RPCs.
186  */
187 
188 struct rpcrdma_rep {
189 	struct ib_cqe		rr_cqe;
190 	struct rpc_rdma_cid	rr_cid;
191 
192 	__be32			rr_xid;
193 	__be32			rr_vers;
194 	__be32			rr_proc;
195 	int			rr_wc_flags;
196 	u32			rr_inv_rkey;
197 	bool			rr_temp;
198 	struct rpcrdma_regbuf	*rr_rdmabuf;
199 	struct rpcrdma_xprt	*rr_rxprt;
200 	struct rpc_rqst		*rr_rqst;
201 	struct xdr_buf		rr_hdrbuf;
202 	struct xdr_stream	rr_stream;
203 	struct llist_node	rr_node;
204 	struct ib_recv_wr	rr_recv_wr;
205 	struct list_head	rr_all;
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 rpc_rdma_cid	sc_cid;
224 	struct rpcrdma_req	*sc_req;
225 	unsigned int		sc_unmap_count;
226 	struct ib_sge		sc_sges[];
227 };
228 
229 /*
230  * struct rpcrdma_mr - external memory region metadata
231  *
232  * An external memory region is any buffer or page that is registered
233  * on the fly (ie, not pre-registered).
234  */
235 struct rpcrdma_req;
236 struct rpcrdma_mr {
237 	struct list_head	mr_list;
238 	struct rpcrdma_req	*mr_req;
239 
240 	struct ib_mr		*mr_ibmr;
241 	struct ib_device	*mr_device;
242 	struct scatterlist	*mr_sg;
243 	int			mr_nents;
244 	enum dma_data_direction	mr_dir;
245 	struct ib_cqe		mr_cqe;
246 	struct completion	mr_linv_done;
247 	union {
248 		struct ib_reg_wr	mr_regwr;
249 		struct ib_send_wr	mr_invwr;
250 	};
251 	struct rpcrdma_xprt	*mr_xprt;
252 	u32			mr_handle;
253 	u32			mr_length;
254 	u64			mr_offset;
255 	struct list_head	mr_all;
256 	struct rpc_rdma_cid	mr_cid;
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 /* Arguments for DMA mapping and registration */
288 struct rpcrdma_mr_seg {
289 	u32		mr_len;		/* length of segment */
290 	struct page	*mr_page;	/* underlying struct page */
291 	u64		mr_offset;	/* IN: page offset, OUT: iova */
292 };
293 
294 /* The Send SGE array is provisioned to send a maximum size
295  * inline request:
296  * - RPC-over-RDMA header
297  * - xdr_buf head iovec
298  * - RPCRDMA_MAX_INLINE bytes, in pages
299  * - xdr_buf tail iovec
300  *
301  * The actual number of array elements consumed by each RPC
302  * depends on the device's max_sge limit.
303  */
304 enum {
305 	RPCRDMA_MIN_SEND_SGES = 3,
306 	RPCRDMA_MAX_PAGE_SGES = RPCRDMA_MAX_INLINE >> PAGE_SHIFT,
307 	RPCRDMA_MAX_SEND_SGES = 1 + 1 + RPCRDMA_MAX_PAGE_SGES + 1,
308 };
309 
310 struct rpcrdma_buffer;
311 struct rpcrdma_req {
312 	struct list_head	rl_list;
313 	struct rpc_rqst		rl_slot;
314 	struct rpcrdma_rep	*rl_reply;
315 	struct xdr_stream	rl_stream;
316 	struct xdr_buf		rl_hdrbuf;
317 	struct ib_send_wr	rl_wr;
318 	struct rpcrdma_sendctx	*rl_sendctx;
319 	struct rpcrdma_regbuf	*rl_rdmabuf;	/* xprt header */
320 	struct rpcrdma_regbuf	*rl_sendbuf;	/* rq_snd_buf */
321 	struct rpcrdma_regbuf	*rl_recvbuf;	/* rq_rcv_buf */
322 
323 	struct list_head	rl_all;
324 	struct kref		rl_kref;
325 
326 	struct list_head	rl_free_mrs;
327 	struct list_head	rl_registered;
328 	struct rpcrdma_mr_seg	rl_segments[RPCRDMA_MAX_SEGS];
329 };
330 
331 static inline struct rpcrdma_req *
rpcr_to_rdmar(const struct rpc_rqst * rqst)332 rpcr_to_rdmar(const struct rpc_rqst *rqst)
333 {
334 	return container_of(rqst, struct rpcrdma_req, rl_slot);
335 }
336 
337 static inline void
rpcrdma_mr_push(struct rpcrdma_mr * mr,struct list_head * list)338 rpcrdma_mr_push(struct rpcrdma_mr *mr, struct list_head *list)
339 {
340 	list_add(&mr->mr_list, list);
341 }
342 
343 static inline struct rpcrdma_mr *
rpcrdma_mr_pop(struct list_head * list)344 rpcrdma_mr_pop(struct list_head *list)
345 {
346 	struct rpcrdma_mr *mr;
347 
348 	mr = list_first_entry_or_null(list, struct rpcrdma_mr, mr_list);
349 	if (mr)
350 		list_del_init(&mr->mr_list);
351 	return mr;
352 }
353 
354 /*
355  * struct rpcrdma_buffer -- holds list/queue of pre-registered memory for
356  * inline requests/replies, and client/server credits.
357  *
358  * One of these is associated with a transport instance
359  */
360 struct rpcrdma_buffer {
361 	spinlock_t		rb_lock;
362 	struct list_head	rb_send_bufs;
363 	struct list_head	rb_mrs;
364 
365 	unsigned long		rb_sc_head;
366 	unsigned long		rb_sc_tail;
367 	unsigned long		rb_sc_last;
368 	struct rpcrdma_sendctx	**rb_sc_ctxs;
369 
370 	struct list_head	rb_allreqs;
371 	struct list_head	rb_all_mrs;
372 	struct list_head	rb_all_reps;
373 
374 	struct llist_head	rb_free_reps;
375 
376 	__be32			rb_max_requests;
377 	u32			rb_credits;	/* most recent credit grant */
378 
379 	u32			rb_bc_srv_max_requests;
380 	u32			rb_bc_max_requests;
381 
382 	struct work_struct	rb_refresh_worker;
383 };
384 
385 /*
386  * Statistics for RPCRDMA
387  */
388 struct rpcrdma_stats {
389 	/* accessed when sending a call */
390 	unsigned long		read_chunk_count;
391 	unsigned long		write_chunk_count;
392 	unsigned long		reply_chunk_count;
393 	unsigned long long	total_rdma_request;
394 
395 	/* rarely accessed error counters */
396 	unsigned long long	pullup_copy_count;
397 	unsigned long		hardway_register_count;
398 	unsigned long		failed_marshal_count;
399 	unsigned long		bad_reply_count;
400 	unsigned long		mrs_recycled;
401 	unsigned long		mrs_orphaned;
402 	unsigned long		mrs_allocated;
403 	unsigned long		empty_sendctx_q;
404 
405 	/* accessed when receiving a reply */
406 	unsigned long long	total_rdma_reply;
407 	unsigned long long	fixup_copy_count;
408 	unsigned long		reply_waits_for_send;
409 	unsigned long		local_inv_needed;
410 	unsigned long		nomsg_call_count;
411 	unsigned long		bcall_count;
412 };
413 
414 /*
415  * RPCRDMA transport -- encapsulates the structures above for
416  * integration with RPC.
417  *
418  * The contained structures are embedded, not pointers,
419  * for convenience. This structure need not be visible externally.
420  *
421  * It is allocated and initialized during mount, and released
422  * during unmount.
423  */
424 struct rpcrdma_xprt {
425 	struct rpc_xprt		rx_xprt;
426 	struct rpcrdma_ep	*rx_ep;
427 	struct rpcrdma_buffer	rx_buf;
428 	struct delayed_work	rx_connect_worker;
429 	struct rpc_timeout	rx_timeout;
430 	struct rpcrdma_stats	rx_stats;
431 };
432 
433 #define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_xprt)
434 
435 static inline const char *
rpcrdma_addrstr(const struct rpcrdma_xprt * r_xprt)436 rpcrdma_addrstr(const struct rpcrdma_xprt *r_xprt)
437 {
438 	return r_xprt->rx_xprt.address_strings[RPC_DISPLAY_ADDR];
439 }
440 
441 static inline const char *
rpcrdma_portstr(const struct rpcrdma_xprt * r_xprt)442 rpcrdma_portstr(const struct rpcrdma_xprt *r_xprt)
443 {
444 	return r_xprt->rx_xprt.address_strings[RPC_DISPLAY_PORT];
445 }
446 
447 /* Setting this to 0 ensures interoperability with early servers.
448  * Setting this to 1 enhances certain unaligned read/write performance.
449  * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */
450 extern int xprt_rdma_pad_optimize;
451 
452 /* This setting controls the hunt for a supported memory
453  * registration strategy.
454  */
455 extern unsigned int xprt_rdma_memreg_strategy;
456 
457 /*
458  * Endpoint calls - xprtrdma/verbs.c
459  */
460 void rpcrdma_force_disconnect(struct rpcrdma_ep *ep);
461 void rpcrdma_flush_disconnect(struct rpcrdma_xprt *r_xprt, struct ib_wc *wc);
462 int rpcrdma_xprt_connect(struct rpcrdma_xprt *r_xprt);
463 void rpcrdma_xprt_disconnect(struct rpcrdma_xprt *r_xprt);
464 
465 void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, int needed, bool temp);
466 
467 /*
468  * Buffer calls - xprtrdma/verbs.c
469  */
470 struct rpcrdma_req *rpcrdma_req_create(struct rpcrdma_xprt *r_xprt, size_t size,
471 				       gfp_t flags);
472 int rpcrdma_req_setup(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req);
473 void rpcrdma_req_destroy(struct rpcrdma_req *req);
474 int rpcrdma_buffer_create(struct rpcrdma_xprt *);
475 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *);
476 struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt);
477 
478 struct rpcrdma_mr *rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt);
479 void rpcrdma_mrs_refresh(struct rpcrdma_xprt *r_xprt);
480 
481 struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *);
482 void rpcrdma_buffer_put(struct rpcrdma_buffer *buffers,
483 			struct rpcrdma_req *req);
484 void rpcrdma_rep_put(struct rpcrdma_buffer *buf, struct rpcrdma_rep *rep);
485 void rpcrdma_reply_put(struct rpcrdma_buffer *buffers, struct rpcrdma_req *req);
486 
487 bool rpcrdma_regbuf_realloc(struct rpcrdma_regbuf *rb, size_t size,
488 			    gfp_t flags);
489 bool __rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt,
490 			      struct rpcrdma_regbuf *rb);
491 
492 /**
493  * rpcrdma_regbuf_is_mapped - check if buffer is DMA mapped
494  *
495  * Returns true if the buffer is now mapped to rb->rg_device.
496  */
rpcrdma_regbuf_is_mapped(struct rpcrdma_regbuf * rb)497 static inline bool rpcrdma_regbuf_is_mapped(struct rpcrdma_regbuf *rb)
498 {
499 	return rb->rg_device != NULL;
500 }
501 
502 /**
503  * rpcrdma_regbuf_dma_map - DMA-map a regbuf
504  * @r_xprt: controlling transport instance
505  * @rb: regbuf to be mapped
506  *
507  * Returns true if the buffer is currently DMA mapped.
508  */
rpcrdma_regbuf_dma_map(struct rpcrdma_xprt * r_xprt,struct rpcrdma_regbuf * rb)509 static inline bool rpcrdma_regbuf_dma_map(struct rpcrdma_xprt *r_xprt,
510 					  struct rpcrdma_regbuf *rb)
511 {
512 	if (likely(rpcrdma_regbuf_is_mapped(rb)))
513 		return true;
514 	return __rpcrdma_regbuf_dma_map(r_xprt, rb);
515 }
516 
517 /*
518  * Wrappers for chunk registration, shared by read/write chunk code.
519  */
520 
521 static inline enum dma_data_direction
rpcrdma_data_dir(bool writing)522 rpcrdma_data_dir(bool writing)
523 {
524 	return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
525 }
526 
527 /* Memory registration calls xprtrdma/frwr_ops.c
528  */
529 void frwr_reset(struct rpcrdma_req *req);
530 int frwr_query_device(struct rpcrdma_ep *ep, const struct ib_device *device);
531 int frwr_mr_init(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr *mr);
532 void frwr_mr_release(struct rpcrdma_mr *mr);
533 struct rpcrdma_mr_seg *frwr_map(struct rpcrdma_xprt *r_xprt,
534 				struct rpcrdma_mr_seg *seg,
535 				int nsegs, bool writing, __be32 xid,
536 				struct rpcrdma_mr *mr);
537 int frwr_send(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req);
538 void frwr_reminv(struct rpcrdma_rep *rep, struct list_head *mrs);
539 void frwr_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req);
540 void frwr_unmap_async(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req);
541 int frwr_wp_create(struct rpcrdma_xprt *r_xprt);
542 
543 /*
544  * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
545  */
546 
547 enum rpcrdma_chunktype {
548 	rpcrdma_noch = 0,
549 	rpcrdma_noch_pullup,
550 	rpcrdma_noch_mapped,
551 	rpcrdma_readch,
552 	rpcrdma_areadch,
553 	rpcrdma_writech,
554 	rpcrdma_replych
555 };
556 
557 int rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt,
558 			      struct rpcrdma_req *req, u32 hdrlen,
559 			      struct xdr_buf *xdr,
560 			      enum rpcrdma_chunktype rtype);
561 void rpcrdma_sendctx_unmap(struct rpcrdma_sendctx *sc);
562 int rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst);
563 void rpcrdma_set_max_header_sizes(struct rpcrdma_ep *ep);
564 void rpcrdma_reset_cwnd(struct rpcrdma_xprt *r_xprt);
565 void rpcrdma_complete_rqst(struct rpcrdma_rep *rep);
566 void rpcrdma_unpin_rqst(struct rpcrdma_rep *rep);
567 void rpcrdma_reply_handler(struct rpcrdma_rep *rep);
568 
rpcrdma_set_xdrlen(struct xdr_buf * xdr,size_t len)569 static inline void rpcrdma_set_xdrlen(struct xdr_buf *xdr, size_t len)
570 {
571 	xdr->head[0].iov_len = len;
572 	xdr->len = len;
573 }
574 
575 /* RPC/RDMA module init - xprtrdma/transport.c
576  */
577 extern unsigned int xprt_rdma_max_inline_read;
578 extern unsigned int xprt_rdma_max_inline_write;
579 void xprt_rdma_format_addresses(struct rpc_xprt *xprt, struct sockaddr *sap);
580 void xprt_rdma_free_addresses(struct rpc_xprt *xprt);
581 void xprt_rdma_close(struct rpc_xprt *xprt);
582 void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq);
583 int xprt_rdma_init(void);
584 void xprt_rdma_cleanup(void);
585 
586 /* Backchannel calls - xprtrdma/backchannel.c
587  */
588 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
589 int xprt_rdma_bc_setup(struct rpc_xprt *, unsigned int);
590 size_t xprt_rdma_bc_maxpayload(struct rpc_xprt *);
591 unsigned int xprt_rdma_bc_max_slots(struct rpc_xprt *);
592 int rpcrdma_bc_post_recv(struct rpcrdma_xprt *, unsigned int);
593 void rpcrdma_bc_receive_call(struct rpcrdma_xprt *, struct rpcrdma_rep *);
594 int xprt_rdma_bc_send_reply(struct rpc_rqst *rqst);
595 void xprt_rdma_bc_free_rqst(struct rpc_rqst *);
596 void xprt_rdma_bc_destroy(struct rpc_xprt *, unsigned int);
597 #endif	/* CONFIG_SUNRPC_BACKCHANNEL */
598 
599 extern struct xprt_class xprt_rdma_bc;
600 
601 #endif				/* _LINUX_SUNRPC_XPRT_RDMA_H */
602