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diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
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1/*
2 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the BSD-type
8 * license below:
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
14 * Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 *
17 * Redistributions in binary form must reproduce the above
18 * copyright notice, this list of conditions and the following
19 * disclaimer in the documentation and/or other materials provided
20 * with the distribution.
21 *
22 * Neither the name of the Network Appliance, Inc. nor the names of
23 * its contributors may be used to endorse or promote products
24 * derived from this software without specific prior written
25 * permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 */
39
40/*
41 * rpc_rdma.c
42 *
43 * This file contains the guts of the RPC RDMA protocol, and
44 * does marshaling/unmarshaling, etc. It is also where interfacing
45 * to the Linux RPC framework lives.
46 */
47
48#include "xprt_rdma.h"
49
50#include <linux/highmem.h>
51
52#ifdef RPC_DEBUG
53# define RPCDBG_FACILITY RPCDBG_TRANS
54#endif
55
56enum rpcrdma_chunktype {
57 rpcrdma_noch = 0,
58 rpcrdma_readch,
59 rpcrdma_areadch,
60 rpcrdma_writech,
61 rpcrdma_replych
62};
63
64#ifdef RPC_DEBUG
65static const char transfertypes[][12] = {
66 "pure inline", /* no chunks */
67 " read chunk", /* some argument via rdma read */
68 "*read chunk", /* entire request via rdma read */
69 "write chunk", /* some result via rdma write */
70 "reply chunk" /* entire reply via rdma write */
71};
72#endif
73
74/*
75 * Chunk assembly from upper layer xdr_buf.
76 *
77 * Prepare the passed-in xdr_buf into representation as RPC/RDMA chunk
78 * elements. Segments are then coalesced when registered, if possible
79 * within the selected memreg mode.
80 *
81 * Note, this routine is never called if the connection's memory
82 * registration strategy is 0 (bounce buffers).
83 */
84
85static int
86rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, int pos,
87 enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg, int nsegs)
88{
89 int len, n = 0, p;
90
91 if (pos == 0 && xdrbuf->head[0].iov_len) {
92 seg[n].mr_page = NULL;
93 seg[n].mr_offset = xdrbuf->head[0].iov_base;
94 seg[n].mr_len = xdrbuf->head[0].iov_len;
95 pos += xdrbuf->head[0].iov_len;
96 ++n;
97 }
98
99 if (xdrbuf->page_len && (xdrbuf->pages[0] != NULL)) {
100 if (n == nsegs)
101 return 0;
102 seg[n].mr_page = xdrbuf->pages[0];
103 seg[n].mr_offset = (void *)(unsigned long) xdrbuf->page_base;
104 seg[n].mr_len = min_t(u32,
105 PAGE_SIZE - xdrbuf->page_base, xdrbuf->page_len);
106 len = xdrbuf->page_len - seg[n].mr_len;
107 pos += len;
108 ++n;
109 p = 1;
110 while (len > 0) {
111 if (n == nsegs)
112 return 0;
113 seg[n].mr_page = xdrbuf->pages[p];
114 seg[n].mr_offset = NULL;
115 seg[n].mr_len = min_t(u32, PAGE_SIZE, len);
116 len -= seg[n].mr_len;
117 ++n;
118 ++p;
119 }
120 }
121
122 if (pos < xdrbuf->len && xdrbuf->tail[0].iov_len) {
123 if (n == nsegs)
124 return 0;
125 seg[n].mr_page = NULL;
126 seg[n].mr_offset = xdrbuf->tail[0].iov_base;
127 seg[n].mr_len = xdrbuf->tail[0].iov_len;
128 pos += xdrbuf->tail[0].iov_len;
129 ++n;
130 }
131
132 if (pos < xdrbuf->len)
133 dprintk("RPC: %s: marshaled only %d of %d\n",
134 __func__, pos, xdrbuf->len);
135
136 return n;
137}
138
139/*
140 * Create read/write chunk lists, and reply chunks, for RDMA
141 *
142 * Assume check against THRESHOLD has been done, and chunks are required.
143 * Assume only encoding one list entry for read|write chunks. The NFSv3
144 * protocol is simple enough to allow this as it only has a single "bulk
145 * result" in each procedure - complicated NFSv4 COMPOUNDs are not. (The
146 * RDMA/Sessions NFSv4 proposal addresses this for future v4 revs.)
147 *
148 * When used for a single reply chunk (which is a special write
149 * chunk used for the entire reply, rather than just the data), it
150 * is used primarily for READDIR and READLINK which would otherwise
151 * be severely size-limited by a small rdma inline read max. The server
152 * response will come back as an RDMA Write, followed by a message
153 * of type RDMA_NOMSG carrying the xid and length. As a result, reply
154 * chunks do not provide data alignment, however they do not require
155 * "fixup" (moving the response to the upper layer buffer) either.
156 *
157 * Encoding key for single-list chunks (HLOO = Handle32 Length32 Offset64):
158 *
159 * Read chunklist (a linked list):
160 * N elements, position P (same P for all chunks of same arg!):
161 * 1 - PHLOO - 1 - PHLOO - ... - 1 - PHLOO - 0
162 *
163 * Write chunklist (a list of (one) counted array):
164 * N elements:
165 * 1 - N - HLOO - HLOO - ... - HLOO - 0
166 *
167 * Reply chunk (a counted array):
168 * N elements:
169 * 1 - N - HLOO - HLOO - ... - HLOO
170 */
171
172static unsigned int
173rpcrdma_create_chunks(struct rpc_rqst *rqst, struct xdr_buf *target,
174 struct rpcrdma_msg *headerp, enum rpcrdma_chunktype type)
175{
176 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
177 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_task->tk_xprt);
178 int nsegs, nchunks = 0;
179 int pos;
180 struct rpcrdma_mr_seg *seg = req->rl_segments;
181 struct rpcrdma_read_chunk *cur_rchunk = NULL;
182 struct rpcrdma_write_array *warray = NULL;
183 struct rpcrdma_write_chunk *cur_wchunk = NULL;
184 u32 *iptr = headerp->rm_body.rm_chunks;
185
186 if (type == rpcrdma_readch || type == rpcrdma_areadch) {
187 /* a read chunk - server will RDMA Read our memory */
188 cur_rchunk = (struct rpcrdma_read_chunk *) iptr;
189 } else {
190 /* a write or reply chunk - server will RDMA Write our memory */
191 *iptr++ = xdr_zero; /* encode a NULL read chunk list */
192 if (type == rpcrdma_replych)
193 *iptr++ = xdr_zero; /* a NULL write chunk list */
194 warray = (struct rpcrdma_write_array *) iptr;
195 cur_wchunk = (struct rpcrdma_write_chunk *) (warray + 1);
196 }
197
198 if (type == rpcrdma_replych || type == rpcrdma_areadch)
199 pos = 0;
200 else
201 pos = target->head[0].iov_len;
202
203 nsegs = rpcrdma_convert_iovs(target, pos, type, seg, RPCRDMA_MAX_SEGS);
204 if (nsegs == 0)
205 return 0;
206
207 do {
208 /* bind/register the memory, then build chunk from result. */
209 int n = rpcrdma_register_external(seg, nsegs,
210 cur_wchunk != NULL, r_xprt);
211 if (n <= 0)
212 goto out;
213 if (cur_rchunk) { /* read */
214 cur_rchunk->rc_discrim = xdr_one;
215 /* all read chunks have the same "position" */
216 cur_rchunk->rc_position = htonl(pos);
217 cur_rchunk->rc_target.rs_handle = htonl(seg->mr_rkey);
218 cur_rchunk->rc_target.rs_length = htonl(seg->mr_len);
219 xdr_encode_hyper(
220 (u32 *)&cur_rchunk->rc_target.rs_offset,
221 seg->mr_base);
222 dprintk("RPC: %s: read chunk "
223 "elem %d@0x%llx:0x%x pos %d (%s)\n", __func__,
224 seg->mr_len, seg->mr_base, seg->mr_rkey, pos,
225 n < nsegs ? "more" : "last");
226 cur_rchunk++;
227 r_xprt->rx_stats.read_chunk_count++;
228 } else { /* write/reply */
229 cur_wchunk->wc_target.rs_handle = htonl(seg->mr_rkey);
230 cur_wchunk->wc_target.rs_length = htonl(seg->mr_len);
231 xdr_encode_hyper(
232 (u32 *)&cur_wchunk->wc_target.rs_offset,
233 seg->mr_base);
234 dprintk("RPC: %s: %s chunk "
235 "elem %d@0x%llx:0x%x (%s)\n", __func__,
236 (type == rpcrdma_replych) ? "reply" : "write",
237 seg->mr_len, seg->mr_base, seg->mr_rkey,
238 n < nsegs ? "more" : "last");
239 cur_wchunk++;
240 if (type == rpcrdma_replych)
241 r_xprt->rx_stats.reply_chunk_count++;
242 else
243 r_xprt->rx_stats.write_chunk_count++;
244 r_xprt->rx_stats.total_rdma_request += seg->mr_len;
245 }
246 nchunks++;
247 seg += n;
248 nsegs -= n;
249 } while (nsegs);
250
251 /* success. all failures return above */
252 req->rl_nchunks = nchunks;
253
254 BUG_ON(nchunks == 0);
255
256 /*
257 * finish off header. If write, marshal discrim and nchunks.
258 */
259 if (cur_rchunk) {
260 iptr = (u32 *) cur_rchunk;
261 *iptr++ = xdr_zero; /* finish the read chunk list */
262 *iptr++ = xdr_zero; /* encode a NULL write chunk list */
263 *iptr++ = xdr_zero; /* encode a NULL reply chunk */
264 } else {
265 warray->wc_discrim = xdr_one;
266 warray->wc_nchunks = htonl(nchunks);
267 iptr = (u32 *) cur_wchunk;
268 if (type == rpcrdma_writech) {
269 *iptr++ = xdr_zero; /* finish the write chunk list */
270 *iptr++ = xdr_zero; /* encode a NULL reply chunk */
271 }
272 }
273
274 /*
275 * Return header size.
276 */
277 return (unsigned char *)iptr - (unsigned char *)headerp;
278
279out:
280 for (pos = 0; nchunks--;)
281 pos += rpcrdma_deregister_external(
282 &req->rl_segments[pos], r_xprt, NULL);
283 return 0;
284}
285
286/*
287 * Copy write data inline.
288 * This function is used for "small" requests. Data which is passed
289 * to RPC via iovecs (or page list) is copied directly into the
290 * pre-registered memory buffer for this request. For small amounts
291 * of data, this is efficient. The cutoff value is tunable.
292 */
293static int
294rpcrdma_inline_pullup(struct rpc_rqst *rqst, int pad)
295{
296 int i, npages, curlen;
297 int copy_len;
298 unsigned char *srcp, *destp;
299 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt);
300
301 destp = rqst->rq_svec[0].iov_base;
302 curlen = rqst->rq_svec[0].iov_len;
303 destp += curlen;
304 /*
305 * Do optional padding where it makes sense. Alignment of write
306 * payload can help the server, if our setting is accurate.
307 */
308 pad -= (curlen + 36/*sizeof(struct rpcrdma_msg_padded)*/);
309 if (pad < 0 || rqst->rq_slen - curlen < RPCRDMA_INLINE_PAD_THRESH)
310 pad = 0; /* don't pad this request */
311
312 dprintk("RPC: %s: pad %d destp 0x%p len %d hdrlen %d\n",
313 __func__, pad, destp, rqst->rq_slen, curlen);
314
315 copy_len = rqst->rq_snd_buf.page_len;
316 r_xprt->rx_stats.pullup_copy_count += copy_len;
317 npages = PAGE_ALIGN(rqst->rq_snd_buf.page_base+copy_len) >> PAGE_SHIFT;
318 for (i = 0; copy_len && i < npages; i++) {
319 if (i == 0)
320 curlen = PAGE_SIZE - rqst->rq_snd_buf.page_base;
321 else
322 curlen = PAGE_SIZE;
323 if (curlen > copy_len)
324 curlen = copy_len;
325 dprintk("RPC: %s: page %d destp 0x%p len %d curlen %d\n",
326 __func__, i, destp, copy_len, curlen);
327 srcp = kmap_atomic(rqst->rq_snd_buf.pages[i],
328 KM_SKB_SUNRPC_DATA);
329 if (i == 0)
330 memcpy(destp, srcp+rqst->rq_snd_buf.page_base, curlen);
331 else
332 memcpy(destp, srcp, curlen);
333 kunmap_atomic(srcp, KM_SKB_SUNRPC_DATA);
334 rqst->rq_svec[0].iov_len += curlen;
335 destp += curlen;
336 copy_len -= curlen;
337 }
338 if (rqst->rq_snd_buf.tail[0].iov_len) {
339 curlen = rqst->rq_snd_buf.tail[0].iov_len;
340 if (destp != rqst->rq_snd_buf.tail[0].iov_base) {
341 memcpy(destp,
342 rqst->rq_snd_buf.tail[0].iov_base, curlen);
343 r_xprt->rx_stats.pullup_copy_count += curlen;
344 }
345 dprintk("RPC: %s: tail destp 0x%p len %d curlen %d\n",
346 __func__, destp, copy_len, curlen);
347 rqst->rq_svec[0].iov_len += curlen;
348 }
349 /* header now contains entire send message */
350 return pad;
351}
352
353/*
354 * Marshal a request: the primary job of this routine is to choose
355 * the transfer modes. See comments below.
356 *
357 * Uses multiple RDMA IOVs for a request:
358 * [0] -- RPC RDMA header, which uses memory from the *start* of the
359 * preregistered buffer that already holds the RPC data in
360 * its middle.
361 * [1] -- the RPC header/data, marshaled by RPC and the NFS protocol.
362 * [2] -- optional padding.
363 * [3] -- if padded, header only in [1] and data here.
364 */
365
366int
367rpcrdma_marshal_req(struct rpc_rqst *rqst)
368{
369 struct rpc_xprt *xprt = rqst->rq_task->tk_xprt;
370 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
371 struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
372 char *base;
373 size_t hdrlen, rpclen, padlen;
374 enum rpcrdma_chunktype rtype, wtype;
375 struct rpcrdma_msg *headerp;
376
377 /*
378 * rpclen gets amount of data in first buffer, which is the
379 * pre-registered buffer.
380 */
381 base = rqst->rq_svec[0].iov_base;
382 rpclen = rqst->rq_svec[0].iov_len;
383
384 /* build RDMA header in private area at front */
385 headerp = (struct rpcrdma_msg *) req->rl_base;
386 /* don't htonl XID, it's already done in request */
387 headerp->rm_xid = rqst->rq_xid;
388 headerp->rm_vers = xdr_one;
389 headerp->rm_credit = htonl(r_xprt->rx_buf.rb_max_requests);
390 headerp->rm_type = __constant_htonl(RDMA_MSG);
391
392 /*
393 * Chunks needed for results?
394 *
395 * o If the expected result is under the inline threshold, all ops
396 * return as inline (but see later).
397 * o Large non-read ops return as a single reply chunk.
398 * o Large read ops return data as write chunk(s), header as inline.
399 *
400 * Note: the NFS code sending down multiple result segments implies
401 * the op is one of read, readdir[plus], readlink or NFSv4 getacl.
402 */
403
404 /*
405 * This code can handle read chunks, write chunks OR reply
406 * chunks -- only one type. If the request is too big to fit
407 * inline, then we will choose read chunks. If the request is
408 * a READ, then use write chunks to separate the file data
409 * into pages; otherwise use reply chunks.
410 */
411 if (rqst->rq_rcv_buf.buflen <= RPCRDMA_INLINE_READ_THRESHOLD(rqst))
412 wtype = rpcrdma_noch;
413 else if (rqst->rq_rcv_buf.page_len == 0)
414 wtype = rpcrdma_replych;
415 else if (rqst->rq_rcv_buf.flags & XDRBUF_READ)
416 wtype = rpcrdma_writech;
417 else
418 wtype = rpcrdma_replych;
419
420 /*
421 * Chunks needed for arguments?
422 *
423 * o If the total request is under the inline threshold, all ops
424 * are sent as inline.
425 * o Large non-write ops are sent with the entire message as a
426 * single read chunk (protocol 0-position special case).
427 * o Large write ops transmit data as read chunk(s), header as
428 * inline.
429 *
430 * Note: the NFS code sending down multiple argument segments
431 * implies the op is a write.
432 * TBD check NFSv4 setacl
433 */
434 if (rqst->rq_snd_buf.len <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst))
435 rtype = rpcrdma_noch;
436 else if (rqst->rq_snd_buf.page_len == 0)
437 rtype = rpcrdma_areadch;
438 else
439 rtype = rpcrdma_readch;
440
441 /* The following simplification is not true forever */
442 if (rtype != rpcrdma_noch && wtype == rpcrdma_replych)
443 wtype = rpcrdma_noch;
444 BUG_ON(rtype != rpcrdma_noch && wtype != rpcrdma_noch);
445
446 if (r_xprt->rx_ia.ri_memreg_strategy == RPCRDMA_BOUNCEBUFFERS &&
447 (rtype != rpcrdma_noch || wtype != rpcrdma_noch)) {
448 /* forced to "pure inline"? */
449 dprintk("RPC: %s: too much data (%d/%d) for inline\n",
450 __func__, rqst->rq_rcv_buf.len, rqst->rq_snd_buf.len);
451 return -1;
452 }
453
454 hdrlen = 28; /*sizeof *headerp;*/
455 padlen = 0;
456
457 /*
458 * Pull up any extra send data into the preregistered buffer.
459 * When padding is in use and applies to the transfer, insert
460 * it and change the message type.
461 */
462 if (rtype == rpcrdma_noch) {
463
464 padlen = rpcrdma_inline_pullup(rqst,
465 RPCRDMA_INLINE_PAD_VALUE(rqst));
466
467 if (padlen) {
468 headerp->rm_type = __constant_htonl(RDMA_MSGP);
469 headerp->rm_body.rm_padded.rm_align =
470 htonl(RPCRDMA_INLINE_PAD_VALUE(rqst));
471 headerp->rm_body.rm_padded.rm_thresh =
472 __constant_htonl(RPCRDMA_INLINE_PAD_THRESH);
473 headerp->rm_body.rm_padded.rm_pempty[0] = xdr_zero;
474 headerp->rm_body.rm_padded.rm_pempty[1] = xdr_zero;
475 headerp->rm_body.rm_padded.rm_pempty[2] = xdr_zero;
476 hdrlen += 2 * sizeof(u32); /* extra words in padhdr */
477 BUG_ON(wtype != rpcrdma_noch);
478
479 } else {
480 headerp->rm_body.rm_nochunks.rm_empty[0] = xdr_zero;
481 headerp->rm_body.rm_nochunks.rm_empty[1] = xdr_zero;
482 headerp->rm_body.rm_nochunks.rm_empty[2] = xdr_zero;
483 /* new length after pullup */
484 rpclen = rqst->rq_svec[0].iov_len;
485 /*
486 * Currently we try to not actually use read inline.
487 * Reply chunks have the desirable property that
488 * they land, packed, directly in the target buffers
489 * without headers, so they require no fixup. The
490 * additional RDMA Write op sends the same amount
491 * of data, streams on-the-wire and adds no overhead
492 * on receive. Therefore, we request a reply chunk
493 * for non-writes wherever feasible and efficient.
494 */
495 if (wtype == rpcrdma_noch &&
496 r_xprt->rx_ia.ri_memreg_strategy > RPCRDMA_REGISTER)
497 wtype = rpcrdma_replych;
498 }
499 }
500
501 /*
502 * Marshal chunks. This routine will return the header length
503 * consumed by marshaling.
504 */
505 if (rtype != rpcrdma_noch) {
506 hdrlen = rpcrdma_create_chunks(rqst,
507 &rqst->rq_snd_buf, headerp, rtype);
508 wtype = rtype; /* simplify dprintk */
509
510 } else if (wtype != rpcrdma_noch) {
511 hdrlen = rpcrdma_create_chunks(rqst,
512 &rqst->rq_rcv_buf, headerp, wtype);
513 }
514
515 if (hdrlen == 0)
516 return -1;
517
518 dprintk("RPC: %s: %s: hdrlen %zd rpclen %zd padlen %zd\n"
519 " headerp 0x%p base 0x%p lkey 0x%x\n",
520 __func__, transfertypes[wtype], hdrlen, rpclen, padlen,
521 headerp, base, req->rl_iov.lkey);
522
523 /*
524 * initialize send_iov's - normally only two: rdma chunk header and
525 * single preregistered RPC header buffer, but if padding is present,
526 * then use a preregistered (and zeroed) pad buffer between the RPC
527 * header and any write data. In all non-rdma cases, any following
528 * data has been copied into the RPC header buffer.
529 */
530 req->rl_send_iov[0].addr = req->rl_iov.addr;
531 req->rl_send_iov[0].length = hdrlen;
532 req->rl_send_iov[0].lkey = req->rl_iov.lkey;
533
534 req->rl_send_iov[1].addr = req->rl_iov.addr + (base - req->rl_base);
535 req->rl_send_iov[1].length = rpclen;
536 req->rl_send_iov[1].lkey = req->rl_iov.lkey;
537
538 req->rl_niovs = 2;
539
540 if (padlen) {
541 struct rpcrdma_ep *ep = &r_xprt->rx_ep;
542
543 req->rl_send_iov[2].addr = ep->rep_pad.addr;
544 req->rl_send_iov[2].length = padlen;
545 req->rl_send_iov[2].lkey = ep->rep_pad.lkey;
546
547 req->rl_send_iov[3].addr = req->rl_send_iov[1].addr + rpclen;
548 req->rl_send_iov[3].length = rqst->rq_slen - rpclen;
549 req->rl_send_iov[3].lkey = req->rl_iov.lkey;
550
551 req->rl_niovs = 4;
552 }
553
554 return 0;
555}
556
557/*
558 * Chase down a received write or reply chunklist to get length
559 * RDMA'd by server. See map at rpcrdma_create_chunks()! :-)
560 */
561static int
562rpcrdma_count_chunks(struct rpcrdma_rep *rep, int max, int wrchunk, u32 **iptrp)
563{
564 unsigned int i, total_len;
565 struct rpcrdma_write_chunk *cur_wchunk;
566
567 i = ntohl(**iptrp); /* get array count */
568 if (i > max)
569 return -1;
570 cur_wchunk = (struct rpcrdma_write_chunk *) (*iptrp + 1);
571 total_len = 0;
572 while (i--) {
573 struct rpcrdma_segment *seg = &cur_wchunk->wc_target;
574 ifdebug(FACILITY) {
575 u64 off;
576 xdr_decode_hyper((u32 *)&seg->rs_offset, &off);
577 dprintk("RPC: %s: chunk %d@0x%llx:0x%x\n",
578 __func__,
579 ntohl(seg->rs_length),
580 off,
581 ntohl(seg->rs_handle));
582 }
583 total_len += ntohl(seg->rs_length);
584 ++cur_wchunk;
585 }
586 /* check and adjust for properly terminated write chunk */
587 if (wrchunk) {
588 u32 *w = (u32 *) cur_wchunk;
589 if (*w++ != xdr_zero)
590 return -1;
591 cur_wchunk = (struct rpcrdma_write_chunk *) w;
592 }
593 if ((char *) cur_wchunk > rep->rr_base + rep->rr_len)
594 return -1;
595
596 *iptrp = (u32 *) cur_wchunk;
597 return total_len;
598}
599
600/*
601 * Scatter inline received data back into provided iov's.
602 */
603static void
604rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len)
605{
606 int i, npages, curlen, olen;
607 char *destp;
608
609 curlen = rqst->rq_rcv_buf.head[0].iov_len;
610 if (curlen > copy_len) { /* write chunk header fixup */
611 curlen = copy_len;
612 rqst->rq_rcv_buf.head[0].iov_len = curlen;
613 }
614
615 dprintk("RPC: %s: srcp 0x%p len %d hdrlen %d\n",
616 __func__, srcp, copy_len, curlen);
617
618 /* Shift pointer for first receive segment only */
619 rqst->rq_rcv_buf.head[0].iov_base = srcp;
620 srcp += curlen;
621 copy_len -= curlen;
622
623 olen = copy_len;
624 i = 0;
625 rpcx_to_rdmax(rqst->rq_xprt)->rx_stats.fixup_copy_count += olen;
626 if (copy_len && rqst->rq_rcv_buf.page_len) {
627 npages = PAGE_ALIGN(rqst->rq_rcv_buf.page_base +
628 rqst->rq_rcv_buf.page_len) >> PAGE_SHIFT;
629 for (; i < npages; i++) {
630 if (i == 0)
631 curlen = PAGE_SIZE - rqst->rq_rcv_buf.page_base;
632 else
633 curlen = PAGE_SIZE;
634 if (curlen > copy_len)
635 curlen = copy_len;
636 dprintk("RPC: %s: page %d"
637 " srcp 0x%p len %d curlen %d\n",
638 __func__, i, srcp, copy_len, curlen);
639 destp = kmap_atomic(rqst->rq_rcv_buf.pages[i],
640 KM_SKB_SUNRPC_DATA);
641 if (i == 0)
642 memcpy(destp + rqst->rq_rcv_buf.page_base,
643 srcp, curlen);
644 else
645 memcpy(destp, srcp, curlen);
646 flush_dcache_page(rqst->rq_rcv_buf.pages[i]);
647 kunmap_atomic(destp, KM_SKB_SUNRPC_DATA);
648 srcp += curlen;
649 copy_len -= curlen;
650 if (copy_len == 0)
651 break;
652 }
653 rqst->rq_rcv_buf.page_len = olen - copy_len;
654 } else
655 rqst->rq_rcv_buf.page_len = 0;
656
657 if (copy_len && rqst->rq_rcv_buf.tail[0].iov_len) {
658 curlen = copy_len;
659 if (curlen > rqst->rq_rcv_buf.tail[0].iov_len)
660 curlen = rqst->rq_rcv_buf.tail[0].iov_len;
661 if (rqst->rq_rcv_buf.tail[0].iov_base != srcp)
662 memcpy(rqst->rq_rcv_buf.tail[0].iov_base, srcp, curlen);
663 dprintk("RPC: %s: tail srcp 0x%p len %d curlen %d\n",
664 __func__, srcp, copy_len, curlen);
665 rqst->rq_rcv_buf.tail[0].iov_len = curlen;
666 copy_len -= curlen; ++i;
667 } else
668 rqst->rq_rcv_buf.tail[0].iov_len = 0;
669
670 if (copy_len)
671 dprintk("RPC: %s: %d bytes in"
672 " %d extra segments (%d lost)\n",
673 __func__, olen, i, copy_len);
674
675 /* TBD avoid a warning from call_decode() */
676 rqst->rq_private_buf = rqst->rq_rcv_buf;
677}
678
679/*
680 * This function is called when an async event is posted to
681 * the connection which changes the connection state. All it
682 * does at this point is mark the connection up/down, the rpc
683 * timers do the rest.
684 */
685void
686rpcrdma_conn_func(struct rpcrdma_ep *ep)
687{
688 struct rpc_xprt *xprt = ep->rep_xprt;
689
690 spin_lock_bh(&xprt->transport_lock);
691 if (ep->rep_connected > 0) {
692 if (!xprt_test_and_set_connected(xprt))
693 xprt_wake_pending_tasks(xprt, 0);
694 } else {
695 if (xprt_test_and_clear_connected(xprt))
696 xprt_wake_pending_tasks(xprt, ep->rep_connected);
697 }
698 spin_unlock_bh(&xprt->transport_lock);
699}
700
701/*
702 * This function is called when memory window unbind which we are waiting
703 * for completes. Just use rr_func (zeroed by upcall) to signal completion.
704 */
705static void
706rpcrdma_unbind_func(struct rpcrdma_rep *rep)
707{
708 wake_up(&rep->rr_unbind);
709}
710
711/*
712 * Called as a tasklet to do req/reply match and complete a request
713 * Errors must result in the RPC task either being awakened, or
714 * allowed to timeout, to discover the errors at that time.
715 */
716void
717rpcrdma_reply_handler(struct rpcrdma_rep *rep)
718{
719 struct rpcrdma_msg *headerp;
720 struct rpcrdma_req *req;
721 struct rpc_rqst *rqst;
722 struct rpc_xprt *xprt = rep->rr_xprt;
723 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
724 u32 *iptr;
725 int i, rdmalen, status;
726
727 /* Check status. If bad, signal disconnect and return rep to pool */
728 if (rep->rr_len == ~0U) {
729 rpcrdma_recv_buffer_put(rep);
730 if (r_xprt->rx_ep.rep_connected == 1) {
731 r_xprt->rx_ep.rep_connected = -EIO;
732 rpcrdma_conn_func(&r_xprt->rx_ep);
733 }
734 return;
735 }
736 if (rep->rr_len < 28) {
737 dprintk("RPC: %s: short/invalid reply\n", __func__);
738 goto repost;
739 }
740 headerp = (struct rpcrdma_msg *) rep->rr_base;
741 if (headerp->rm_vers != xdr_one) {
742 dprintk("RPC: %s: invalid version %d\n",
743 __func__, ntohl(headerp->rm_vers));
744 goto repost;
745 }
746
747 /* Get XID and try for a match. */
748 spin_lock(&xprt->transport_lock);
749 rqst = xprt_lookup_rqst(xprt, headerp->rm_xid);
750 if (rqst == NULL) {
751 spin_unlock(&xprt->transport_lock);
752 dprintk("RPC: %s: reply 0x%p failed "
753 "to match any request xid 0x%08x len %d\n",
754 __func__, rep, headerp->rm_xid, rep->rr_len);
755repost:
756 r_xprt->rx_stats.bad_reply_count++;
757 rep->rr_func = rpcrdma_reply_handler;
758 if (rpcrdma_ep_post_recv(&r_xprt->rx_ia, &r_xprt->rx_ep, rep))
759 rpcrdma_recv_buffer_put(rep);
760
761 return;
762 }
763
764 /* get request object */
765 req = rpcr_to_rdmar(rqst);
766
767 dprintk("RPC: %s: reply 0x%p completes request 0x%p\n"
768 " RPC request 0x%p xid 0x%08x\n",
769 __func__, rep, req, rqst, headerp->rm_xid);
770
771 BUG_ON(!req || req->rl_reply);
772
773 /* from here on, the reply is no longer an orphan */
774 req->rl_reply = rep;
775
776 /* check for expected message types */
777 /* The order of some of these tests is important. */
778 switch (headerp->rm_type) {
779 case __constant_htonl(RDMA_MSG):
780 /* never expect read chunks */
781 /* never expect reply chunks (two ways to check) */
782 /* never expect write chunks without having offered RDMA */
783 if (headerp->rm_body.rm_chunks[0] != xdr_zero ||
784 (headerp->rm_body.rm_chunks[1] == xdr_zero &&
785 headerp->rm_body.rm_chunks[2] != xdr_zero) ||
786 (headerp->rm_body.rm_chunks[1] != xdr_zero &&
787 req->rl_nchunks == 0))
788 goto badheader;
789 if (headerp->rm_body.rm_chunks[1] != xdr_zero) {
790 /* count any expected write chunks in read reply */
791 /* start at write chunk array count */
792 iptr = &headerp->rm_body.rm_chunks[2];
793 rdmalen = rpcrdma_count_chunks(rep,
794 req->rl_nchunks, 1, &iptr);
795 /* check for validity, and no reply chunk after */
796 if (rdmalen < 0 || *iptr++ != xdr_zero)
797 goto badheader;
798 rep->rr_len -=
799 ((unsigned char *)iptr - (unsigned char *)headerp);
800 status = rep->rr_len + rdmalen;
801 r_xprt->rx_stats.total_rdma_reply += rdmalen;
802 } else {
803 /* else ordinary inline */
804 iptr = (u32 *)((unsigned char *)headerp + 28);
805 rep->rr_len -= 28; /*sizeof *headerp;*/
806 status = rep->rr_len;
807 }
808 /* Fix up the rpc results for upper layer */
809 rpcrdma_inline_fixup(rqst, (char *)iptr, rep->rr_len);
810 break;
811
812 case __constant_htonl(RDMA_NOMSG):
813 /* never expect read or write chunks, always reply chunks */
814 if (headerp->rm_body.rm_chunks[0] != xdr_zero ||
815 headerp->rm_body.rm_chunks[1] != xdr_zero ||
816 headerp->rm_body.rm_chunks[2] != xdr_one ||
817 req->rl_nchunks == 0)
818 goto badheader;
819 iptr = (u32 *)((unsigned char *)headerp + 28);
820 rdmalen = rpcrdma_count_chunks(rep, req->rl_nchunks, 0, &iptr);
821 if (rdmalen < 0)
822 goto badheader;
823 r_xprt->rx_stats.total_rdma_reply += rdmalen;
824 /* Reply chunk buffer already is the reply vector - no fixup. */
825 status = rdmalen;
826 break;
827
828badheader:
829 default:
830 dprintk("%s: invalid rpcrdma reply header (type %d):"
831 " chunks[012] == %d %d %d"
832 " expected chunks <= %d\n",
833 __func__, ntohl(headerp->rm_type),
834 headerp->rm_body.rm_chunks[0],
835 headerp->rm_body.rm_chunks[1],
836 headerp->rm_body.rm_chunks[2],
837 req->rl_nchunks);
838 status = -EIO;
839 r_xprt->rx_stats.bad_reply_count++;
840 break;
841 }
842
843 /* If using mw bind, start the deregister process now. */
844 /* (Note: if mr_free(), cannot perform it here, in tasklet context) */
845 if (req->rl_nchunks) switch (r_xprt->rx_ia.ri_memreg_strategy) {
846 case RPCRDMA_MEMWINDOWS:
847 for (i = 0; req->rl_nchunks-- > 1;)
848 i += rpcrdma_deregister_external(
849 &req->rl_segments[i], r_xprt, NULL);
850 /* Optionally wait (not here) for unbinds to complete */
851 rep->rr_func = rpcrdma_unbind_func;
852 (void) rpcrdma_deregister_external(&req->rl_segments[i],
853 r_xprt, rep);
854 break;
855 case RPCRDMA_MEMWINDOWS_ASYNC:
856 for (i = 0; req->rl_nchunks--;)
857 i += rpcrdma_deregister_external(&req->rl_segments[i],
858 r_xprt, NULL);
859 break;
860 default:
861 break;
862 }
863
864 dprintk("RPC: %s: xprt_complete_rqst(0x%p, 0x%p, %d)\n",
865 __func__, xprt, rqst, status);
866 xprt_complete_rqst(rqst->rq_task, status);
867 spin_unlock(&xprt->transport_lock);
868}
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-27 17:31:13 -0500