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, unsigned 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 ++n; 96 } 97 98 if (xdrbuf->page_len && (xdrbuf->pages[0] != NULL)) { 99 if (n == nsegs) 100 return 0; 101 seg[n].mr_page = xdrbuf->pages[0]; 102 seg[n].mr_offset = (void *)(unsigned long) xdrbuf->page_base; 103 seg[n].mr_len = min_t(u32, 104 PAGE_SIZE - xdrbuf->page_base, xdrbuf->page_len); 105 len = xdrbuf->page_len - seg[n].mr_len; 106 ++n; 107 p = 1; 108 while (len > 0) { 109 if (n == nsegs) 110 return 0; 111 seg[n].mr_page = xdrbuf->pages[p]; 112 seg[n].mr_offset = NULL; 113 seg[n].mr_len = min_t(u32, PAGE_SIZE, len); 114 len -= seg[n].mr_len; 115 ++n; 116 ++p; 117 } 118 } 119 120 if (xdrbuf->tail[0].iov_len) { 121 /* the rpcrdma protocol allows us to omit any trailing 122 * xdr pad bytes, saving the server an RDMA operation. */ 123 if (xdrbuf->tail[0].iov_len < 4 && xprt_rdma_pad_optimize) 124 return n; 125 if (n == nsegs) 126 return 0; 127 seg[n].mr_page = NULL; 128 seg[n].mr_offset = xdrbuf->tail[0].iov_base; 129 seg[n].mr_len = xdrbuf->tail[0].iov_len; 130 ++n; 131 } 132 133 return n; 134} 135 136/* 137 * Create read/write chunk lists, and reply chunks, for RDMA 138 * 139 * Assume check against THRESHOLD has been done, and chunks are required. 140 * Assume only encoding one list entry for read|write chunks. The NFSv3 141 * protocol is simple enough to allow this as it only has a single "bulk 142 * result" in each procedure - complicated NFSv4 COMPOUNDs are not. (The 143 * RDMA/Sessions NFSv4 proposal addresses this for future v4 revs.) 144 * 145 * When used for a single reply chunk (which is a special write 146 * chunk used for the entire reply, rather than just the data), it 147 * is used primarily for READDIR and READLINK which would otherwise 148 * be severely size-limited by a small rdma inline read max. The server 149 * response will come back as an RDMA Write, followed by a message 150 * of type RDMA_NOMSG carrying the xid and length. As a result, reply 151 * chunks do not provide data alignment, however they do not require 152 * "fixup" (moving the response to the upper layer buffer) either. 153 * 154 * Encoding key for single-list chunks (HLOO = Handle32 Length32 Offset64): 155 * 156 * Read chunklist (a linked list): 157 * N elements, position P (same P for all chunks of same arg!): 158 * 1 - PHLOO - 1 - PHLOO - ... - 1 - PHLOO - 0 159 * 160 * Write chunklist (a list of (one) counted array): 161 * N elements: 162 * 1 - N - HLOO - HLOO - ... - HLOO - 0 163 * 164 * Reply chunk (a counted array): 165 * N elements: 166 * 1 - N - HLOO - HLOO - ... - HLOO 167 */ 168 169static unsigned int 170rpcrdma_create_chunks(struct rpc_rqst *rqst, struct xdr_buf *target, 171 struct rpcrdma_msg *headerp, enum rpcrdma_chunktype type) 172{ 173 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 174 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_task->tk_xprt); 175 int nsegs, nchunks = 0; 176 unsigned int pos; 177 struct rpcrdma_mr_seg *seg = req->rl_segments; 178 struct rpcrdma_read_chunk *cur_rchunk = NULL; 179 struct rpcrdma_write_array *warray = NULL; 180 struct rpcrdma_write_chunk *cur_wchunk = NULL; 181 __be32 *iptr = headerp->rm_body.rm_chunks; 182 183 if (type == rpcrdma_readch || type == rpcrdma_areadch) { 184 /* a read chunk - server will RDMA Read our memory */ 185 cur_rchunk = (struct rpcrdma_read_chunk *) iptr; 186 } else { 187 /* a write or reply chunk - server will RDMA Write our memory */ 188 *iptr++ = xdr_zero; /* encode a NULL read chunk list */ 189 if (type == rpcrdma_replych) 190 *iptr++ = xdr_zero; /* a NULL write chunk list */ 191 warray = (struct rpcrdma_write_array *) iptr; 192 cur_wchunk = (struct rpcrdma_write_chunk *) (warray + 1); 193 } 194 195 if (type == rpcrdma_replych || type == rpcrdma_areadch) 196 pos = 0; 197 else 198 pos = target->head[0].iov_len; 199 200 nsegs = rpcrdma_convert_iovs(target, pos, type, seg, RPCRDMA_MAX_SEGS); 201 if (nsegs == 0) 202 return 0; 203 204 do { 205 /* bind/register the memory, then build chunk from result. */ 206 int n = rpcrdma_register_external(seg, nsegs, 207 cur_wchunk != NULL, r_xprt); 208 if (n <= 0) 209 goto out; 210 if (cur_rchunk) { /* read */ 211 cur_rchunk->rc_discrim = xdr_one; 212 /* all read chunks have the same "position" */ 213 cur_rchunk->rc_position = htonl(pos); 214 cur_rchunk->rc_target.rs_handle = htonl(seg->mr_rkey); 215 cur_rchunk->rc_target.rs_length = htonl(seg->mr_len); 216 xdr_encode_hyper( 217 (__be32 *)&cur_rchunk->rc_target.rs_offset, 218 seg->mr_base); 219 dprintk("RPC: %s: read chunk " 220 "elem %d@0x%llx:0x%x pos %u (%s)\n", __func__, 221 seg->mr_len, (unsigned long long)seg->mr_base, 222 seg->mr_rkey, pos, n < nsegs ? "more" : "last"); 223 cur_rchunk++; 224 r_xprt->rx_stats.read_chunk_count++; 225 } else { /* write/reply */ 226 cur_wchunk->wc_target.rs_handle = htonl(seg->mr_rkey); 227 cur_wchunk->wc_target.rs_length = htonl(seg->mr_len); 228 xdr_encode_hyper( 229 (__be32 *)&cur_wchunk->wc_target.rs_offset, 230 seg->mr_base); 231 dprintk("RPC: %s: %s chunk " 232 "elem %d@0x%llx:0x%x (%s)\n", __func__, 233 (type == rpcrdma_replych) ? "reply" : "write", 234 seg->mr_len, (unsigned long long)seg->mr_base, 235 seg->mr_rkey, n < nsegs ? "more" : "last"); 236 cur_wchunk++; 237 if (type == rpcrdma_replych) 238 r_xprt->rx_stats.reply_chunk_count++; 239 else 240 r_xprt->rx_stats.write_chunk_count++; 241 r_xprt->rx_stats.total_rdma_request += seg->mr_len; 242 } 243 nchunks++; 244 seg += n; 245 nsegs -= n; 246 } while (nsegs); 247 248 /* success. all failures return above */ 249 req->rl_nchunks = nchunks; 250 251 BUG_ON(nchunks == 0); 252 BUG_ON((r_xprt->rx_ia.ri_memreg_strategy == RPCRDMA_FRMR) 253 && (nchunks > 3)); 254 255 /* 256 * finish off header. If write, marshal discrim and nchunks. 257 */ 258 if (cur_rchunk) { 259 iptr = (__be32 *) cur_rchunk; 260 *iptr++ = xdr_zero; /* finish the read chunk list */ 261 *iptr++ = xdr_zero; /* encode a NULL write chunk list */ 262 *iptr++ = xdr_zero; /* encode a NULL reply chunk */ 263 } else { 264 warray->wc_discrim = xdr_one; 265 warray->wc_nchunks = htonl(nchunks); 266 iptr = (__be32 *) cur_wchunk; 267 if (type == rpcrdma_writech) { 268 *iptr++ = xdr_zero; /* finish the write chunk list */ 269 *iptr++ = xdr_zero; /* encode a NULL reply chunk */ 270 } 271 } 272 273 /* 274 * Return header size. 275 */ 276 return (unsigned char *)iptr - (unsigned char *)headerp; 277 278out: 279 for (pos = 0; nchunks--;) 280 pos += rpcrdma_deregister_external( 281 &req->rl_segments[pos], r_xprt, NULL); 282 return 0; 283} 284 285/* 286 * Copy write data inline. 287 * This function is used for "small" requests. Data which is passed 288 * to RPC via iovecs (or page list) is copied directly into the 289 * pre-registered memory buffer for this request. For small amounts 290 * of data, this is efficient. The cutoff value is tunable. 291 */ 292static int 293rpcrdma_inline_pullup(struct rpc_rqst *rqst, int pad) 294{ 295 int i, npages, curlen; 296 int copy_len; 297 unsigned char *srcp, *destp; 298 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); 299 300 destp = rqst->rq_svec[0].iov_base; 301 curlen = rqst->rq_svec[0].iov_len; 302 destp += curlen; 303 /* 304 * Do optional padding where it makes sense. Alignment of write 305 * payload can help the server, if our setting is accurate. 306 */ 307 pad -= (curlen + 36/*sizeof(struct rpcrdma_msg_padded)*/); 308 if (pad < 0 || rqst->rq_slen - curlen < RPCRDMA_INLINE_PAD_THRESH) 309 pad = 0; /* don't pad this request */ 310 311 dprintk("RPC: %s: pad %d destp 0x%p len %d hdrlen %d\n", 312 __func__, pad, destp, rqst->rq_slen, curlen); 313 314 copy_len = rqst->rq_snd_buf.page_len; 315 316 if (rqst->rq_snd_buf.tail[0].iov_len) { 317 curlen = rqst->rq_snd_buf.tail[0].iov_len; 318 if (destp + copy_len != rqst->rq_snd_buf.tail[0].iov_base) { 319 memmove(destp + copy_len, 320 rqst->rq_snd_buf.tail[0].iov_base, curlen); 321 r_xprt->rx_stats.pullup_copy_count += curlen; 322 } 323 dprintk("RPC: %s: tail destp 0x%p len %d\n", 324 __func__, destp + copy_len, curlen); 325 rqst->rq_svec[0].iov_len += curlen; 326 } 327 328 r_xprt->rx_stats.pullup_copy_count += copy_len; 329 npages = PAGE_ALIGN(rqst->rq_snd_buf.page_base+copy_len) >> PAGE_SHIFT; 330 for (i = 0; copy_len && i < npages; i++) { 331 if (i == 0) 332 curlen = PAGE_SIZE - rqst->rq_snd_buf.page_base; 333 else 334 curlen = PAGE_SIZE; 335 if (curlen > copy_len) 336 curlen = copy_len; 337 dprintk("RPC: %s: page %d destp 0x%p len %d curlen %d\n", 338 __func__, i, destp, copy_len, curlen); 339 srcp = kmap_atomic(rqst->rq_snd_buf.pages[i], 340 KM_SKB_SUNRPC_DATA); 341 if (i == 0) 342 memcpy(destp, srcp+rqst->rq_snd_buf.page_base, curlen); 343 else 344 memcpy(destp, srcp, curlen); 345 kunmap_atomic(srcp, KM_SKB_SUNRPC_DATA); 346 rqst->rq_svec[0].iov_len += curlen; 347 destp += curlen; 348 copy_len -= curlen; 349 } 350 /* header now contains entire send message */ 351 return pad; 352} 353 354/* 355 * Marshal a request: the primary job of this routine is to choose 356 * the transfer modes. See comments below. 357 * 358 * Uses multiple RDMA IOVs for a request: 359 * [0] -- RPC RDMA header, which uses memory from the *start* of the 360 * preregistered buffer that already holds the RPC data in 361 * its middle. 362 * [1] -- the RPC header/data, marshaled by RPC and the NFS protocol. 363 * [2] -- optional padding. 364 * [3] -- if padded, header only in [1] and data here. 365 */ 366 367int 368rpcrdma_marshal_req(struct rpc_rqst *rqst) 369{ 370 struct rpc_xprt *xprt = rqst->rq_task->tk_xprt; 371 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 372 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 373 char *base; 374 size_t hdrlen, rpclen, padlen; 375 enum rpcrdma_chunktype rtype, wtype; 376 struct rpcrdma_msg *headerp; 377 378 /* 379 * rpclen gets amount of data in first buffer, which is the 380 * pre-registered buffer. 381 */ 382 base = rqst->rq_svec[0].iov_base; 383 rpclen = rqst->rq_svec[0].iov_len; 384 385 /* build RDMA header in private area at front */ 386 headerp = (struct rpcrdma_msg *) req->rl_base; 387 /* don't htonl XID, it's already done in request */ 388 headerp->rm_xid = rqst->rq_xid; 389 headerp->rm_vers = xdr_one; 390 headerp->rm_credit = htonl(r_xprt->rx_buf.rb_max_requests); 391 headerp->rm_type = htonl(RDMA_MSG); 392 393 /* 394 * Chunks needed for results? 395 * 396 * o If the expected result is under the inline threshold, all ops 397 * return as inline (but see later). 398 * o Large non-read ops return as a single reply chunk. 399 * o Large read ops return data as write chunk(s), header as inline. 400 * 401 * Note: the NFS code sending down multiple result segments implies 402 * the op is one of read, readdir[plus], readlink or NFSv4 getacl. 403 */ 404 405 /* 406 * This code can handle read chunks, write chunks OR reply 407 * chunks -- only one type. If the request is too big to fit 408 * inline, then we will choose read chunks. If the request is 409 * a READ, then use write chunks to separate the file data 410 * into pages; otherwise use reply chunks. 411 */ 412 if (rqst->rq_rcv_buf.buflen <= RPCRDMA_INLINE_READ_THRESHOLD(rqst)) 413 wtype = rpcrdma_noch; 414 else if (rqst->rq_rcv_buf.page_len == 0) 415 wtype = rpcrdma_replych; 416 else if (rqst->rq_rcv_buf.flags & XDRBUF_READ) 417 wtype = rpcrdma_writech; 418 else 419 wtype = rpcrdma_replych; 420 421 /* 422 * Chunks needed for arguments? 423 * 424 * o If the total request is under the inline threshold, all ops 425 * are sent as inline. 426 * o Large non-write ops are sent with the entire message as a 427 * single read chunk (protocol 0-position special case). 428 * o Large write ops transmit data as read chunk(s), header as 429 * inline. 430 * 431 * Note: the NFS code sending down multiple argument segments 432 * implies the op is a write. 433 * TBD check NFSv4 setacl 434 */ 435 if (rqst->rq_snd_buf.len <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst)) 436 rtype = rpcrdma_noch; 437 else if (rqst->rq_snd_buf.page_len == 0) 438 rtype = rpcrdma_areadch; 439 else 440 rtype = rpcrdma_readch; 441 442 /* The following simplification is not true forever */ 443 if (rtype != rpcrdma_noch && wtype == rpcrdma_replych) 444 wtype = rpcrdma_noch; 445 BUG_ON(rtype != rpcrdma_noch && wtype != rpcrdma_noch); 446 447 if (r_xprt->rx_ia.ri_memreg_strategy == RPCRDMA_BOUNCEBUFFERS && 448 (rtype != rpcrdma_noch || wtype != rpcrdma_noch)) { 449 /* forced to "pure inline"? */ 450 dprintk("RPC: %s: too much data (%d/%d) for inline\n", 451 __func__, rqst->rq_rcv_buf.len, rqst->rq_snd_buf.len); 452 return -1; 453 } 454 455 hdrlen = 28; /*sizeof *headerp;*/ 456 padlen = 0; 457 458 /* 459 * Pull up any extra send data into the preregistered buffer. 460 * When padding is in use and applies to the transfer, insert 461 * it and change the message type. 462 */ 463 if (rtype == rpcrdma_noch) { 464 465 padlen = rpcrdma_inline_pullup(rqst, 466 RPCRDMA_INLINE_PAD_VALUE(rqst)); 467 468 if (padlen) { 469 headerp->rm_type = htonl(RDMA_MSGP); 470 headerp->rm_body.rm_padded.rm_align = 471 htonl(RPCRDMA_INLINE_PAD_VALUE(rqst)); 472 headerp->rm_body.rm_padded.rm_thresh = 473 htonl(RPCRDMA_INLINE_PAD_THRESH); 474 headerp->rm_body.rm_padded.rm_pempty[0] = xdr_zero; 475 headerp->rm_body.rm_padded.rm_pempty[1] = xdr_zero; 476 headerp->rm_body.rm_padded.rm_pempty[2] = xdr_zero; 477 hdrlen += 2 * sizeof(u32); /* extra words in padhdr */ 478 BUG_ON(wtype != rpcrdma_noch); 479 480 } else { 481 headerp->rm_body.rm_nochunks.rm_empty[0] = xdr_zero; 482 headerp->rm_body.rm_nochunks.rm_empty[1] = xdr_zero; 483 headerp->rm_body.rm_nochunks.rm_empty[2] = xdr_zero; 484 /* new length after pullup */ 485 rpclen = rqst->rq_svec[0].iov_len; 486 /* 487 * Currently we try to not actually use read inline. 488 * Reply chunks have the desirable property that 489 * they land, packed, directly in the target buffers 490 * without headers, so they require no fixup. The 491 * additional RDMA Write op sends the same amount 492 * of data, streams on-the-wire and adds no overhead 493 * on receive. Therefore, we request a reply chunk 494 * for non-writes wherever feasible and efficient. 495 */ 496 if (wtype == rpcrdma_noch && 497 r_xprt->rx_ia.ri_memreg_strategy > RPCRDMA_REGISTER) 498 wtype = rpcrdma_replych; 499 } 500 } 501 502 /* 503 * Marshal chunks. This routine will return the header length 504 * consumed by marshaling. 505 */ 506 if (rtype != rpcrdma_noch) { 507 hdrlen = rpcrdma_create_chunks(rqst, 508 &rqst->rq_snd_buf, headerp, rtype); 509 wtype = rtype; /* simplify dprintk */ 510 511 } else if (wtype != rpcrdma_noch) { 512 hdrlen = rpcrdma_create_chunks(rqst, 513 &rqst->rq_rcv_buf, headerp, wtype); 514 } 515 516 if (hdrlen == 0) 517 return -1; 518 519 dprintk("RPC: %s: %s: hdrlen %zd rpclen %zd padlen %zd" 520 " headerp 0x%p base 0x%p lkey 0x%x\n", 521 __func__, transfertypes[wtype], hdrlen, rpclen, padlen, 522 headerp, base, req->rl_iov.lkey); 523 524 /* 525 * initialize send_iov's - normally only two: rdma chunk header and 526 * single preregistered RPC header buffer, but if padding is present, 527 * then use a preregistered (and zeroed) pad buffer between the RPC 528 * header and any write data. In all non-rdma cases, any following 529 * data has been copied into the RPC header buffer. 530 */ 531 req->rl_send_iov[0].addr = req->rl_iov.addr; 532 req->rl_send_iov[0].length = hdrlen; 533 req->rl_send_iov[0].lkey = req->rl_iov.lkey; 534 535 req->rl_send_iov[1].addr = req->rl_iov.addr + (base - req->rl_base); 536 req->rl_send_iov[1].length = rpclen; 537 req->rl_send_iov[1].lkey = req->rl_iov.lkey; 538 539 req->rl_niovs = 2; 540 541 if (padlen) { 542 struct rpcrdma_ep *ep = &r_xprt->rx_ep; 543 544 req->rl_send_iov[2].addr = ep->rep_pad.addr; 545 req->rl_send_iov[2].length = padlen; 546 req->rl_send_iov[2].lkey = ep->rep_pad.lkey; 547 548 req->rl_send_iov[3].addr = req->rl_send_iov[1].addr + rpclen; 549 req->rl_send_iov[3].length = rqst->rq_slen - rpclen; 550 req->rl_send_iov[3].lkey = req->rl_iov.lkey; 551 552 req->rl_niovs = 4; 553 } 554 555 return 0; 556} 557 558/* 559 * Chase down a received write or reply chunklist to get length 560 * RDMA'd by server. See map at rpcrdma_create_chunks()! :-) 561 */ 562static int 563rpcrdma_count_chunks(struct rpcrdma_rep *rep, unsigned int max, int wrchunk, __be32 **iptrp) 564{ 565 unsigned int i, total_len; 566 struct rpcrdma_write_chunk *cur_wchunk; 567 568 i = ntohl(**iptrp); /* get array count */ 569 if (i > max) 570 return -1; 571 cur_wchunk = (struct rpcrdma_write_chunk *) (*iptrp + 1); 572 total_len = 0; 573 while (i--) { 574 struct rpcrdma_segment *seg = &cur_wchunk->wc_target; 575 ifdebug(FACILITY) { 576 u64 off; 577 xdr_decode_hyper((__be32 *)&seg->rs_offset, &off); 578 dprintk("RPC: %s: chunk %d@0x%llx:0x%x\n", 579 __func__, 580 ntohl(seg->rs_length), 581 (unsigned long long)off, 582 ntohl(seg->rs_handle)); 583 } 584 total_len += ntohl(seg->rs_length); 585 ++cur_wchunk; 586 } 587 /* check and adjust for properly terminated write chunk */ 588 if (wrchunk) { 589 __be32 *w = (__be32 *) cur_wchunk; 590 if (*w++ != xdr_zero) 591 return -1; 592 cur_wchunk = (struct rpcrdma_write_chunk *) w; 593 } 594 if ((char *) cur_wchunk > rep->rr_base + rep->rr_len) 595 return -1; 596 597 *iptrp = (__be32 *) cur_wchunk; 598 return total_len; 599} 600 601/* 602 * Scatter inline received data back into provided iov's. 603 */ 604static void 605rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad) 606{ 607 int i, npages, curlen, olen; 608 char *destp; 609 610 curlen = rqst->rq_rcv_buf.head[0].iov_len; 611 if (curlen > copy_len) { /* write chunk header fixup */ 612 curlen = copy_len; 613 rqst->rq_rcv_buf.head[0].iov_len = curlen; 614 } 615 616 dprintk("RPC: %s: srcp 0x%p len %d hdrlen %d\n", 617 __func__, srcp, copy_len, curlen); 618 619 /* Shift pointer for first receive segment only */ 620 rqst->rq_rcv_buf.head[0].iov_base = srcp; 621 srcp += curlen; 622 copy_len -= curlen; 623 624 olen = copy_len; 625 i = 0; 626 rpcx_to_rdmax(rqst->rq_xprt)->rx_stats.fixup_copy_count += olen; 627 if (copy_len && rqst->rq_rcv_buf.page_len) { 628 npages = PAGE_ALIGN(rqst->rq_rcv_buf.page_base + 629 rqst->rq_rcv_buf.page_len) >> PAGE_SHIFT; 630 for (; i < npages; i++) { 631 if (i == 0) 632 curlen = PAGE_SIZE - rqst->rq_rcv_buf.page_base; 633 else 634 curlen = PAGE_SIZE; 635 if (curlen > copy_len) 636 curlen = copy_len; 637 dprintk("RPC: %s: page %d" 638 " srcp 0x%p len %d curlen %d\n", 639 __func__, i, srcp, copy_len, curlen); 640 destp = kmap_atomic(rqst->rq_rcv_buf.pages[i], 641 KM_SKB_SUNRPC_DATA); 642 if (i == 0) 643 memcpy(destp + rqst->rq_rcv_buf.page_base, 644 srcp, curlen); 645 else 646 memcpy(destp, srcp, curlen); 647 flush_dcache_page(rqst->rq_rcv_buf.pages[i]); 648 kunmap_atomic(destp, KM_SKB_SUNRPC_DATA); 649 srcp += curlen; 650 copy_len -= curlen; 651 if (copy_len == 0) 652 break; 653 } 654 rqst->rq_rcv_buf.page_len = olen - copy_len; 655 } else 656 rqst->rq_rcv_buf.page_len = 0; 657 658 if (copy_len && rqst->rq_rcv_buf.tail[0].iov_len) { 659 curlen = copy_len; 660 if (curlen > rqst->rq_rcv_buf.tail[0].iov_len) 661 curlen = rqst->rq_rcv_buf.tail[0].iov_len; 662 if (rqst->rq_rcv_buf.tail[0].iov_base != srcp) 663 memmove(rqst->rq_rcv_buf.tail[0].iov_base, srcp, curlen); 664 dprintk("RPC: %s: tail srcp 0x%p len %d curlen %d\n", 665 __func__, srcp, copy_len, curlen); 666 rqst->rq_rcv_buf.tail[0].iov_len = curlen; 667 copy_len -= curlen; ++i; 668 } else 669 rqst->rq_rcv_buf.tail[0].iov_len = 0; 670 671 if (pad) { 672 /* implicit padding on terminal chunk */ 673 unsigned char *p = rqst->rq_rcv_buf.tail[0].iov_base; 674 while (pad--) 675 p[rqst->rq_rcv_buf.tail[0].iov_len++] = 0; 676 } 677 678 if (copy_len) 679 dprintk("RPC: %s: %d bytes in" 680 " %d extra segments (%d lost)\n", 681 __func__, olen, i, copy_len); 682 683 /* TBD avoid a warning from call_decode() */ 684 rqst->rq_private_buf = rqst->rq_rcv_buf; 685} 686 687/* 688 * This function is called when an async event is posted to 689 * the connection which changes the connection state. All it 690 * does at this point is mark the connection up/down, the rpc 691 * timers do the rest. 692 */ 693void 694rpcrdma_conn_func(struct rpcrdma_ep *ep) 695{ 696 struct rpc_xprt *xprt = ep->rep_xprt; 697 698 spin_lock_bh(&xprt->transport_lock); 699 if (++xprt->connect_cookie == 0) /* maintain a reserved value */ 700 ++xprt->connect_cookie; 701 if (ep->rep_connected > 0) { 702 if (!xprt_test_and_set_connected(xprt)) 703 xprt_wake_pending_tasks(xprt, 0); 704 } else { 705 if (xprt_test_and_clear_connected(xprt)) 706 xprt_wake_pending_tasks(xprt, -ENOTCONN); 707 } 708 spin_unlock_bh(&xprt->transport_lock); 709} 710 711/* 712 * This function is called when memory window unbind which we are waiting 713 * for completes. Just use rr_func (zeroed by upcall) to signal completion. 714 */ 715static void 716rpcrdma_unbind_func(struct rpcrdma_rep *rep) 717{ 718 wake_up(&rep->rr_unbind); 719} 720 721/* 722 * Called as a tasklet to do req/reply match and complete a request 723 * Errors must result in the RPC task either being awakened, or 724 * allowed to timeout, to discover the errors at that time. 725 */ 726void 727rpcrdma_reply_handler(struct rpcrdma_rep *rep) 728{ 729 struct rpcrdma_msg *headerp; 730 struct rpcrdma_req *req; 731 struct rpc_rqst *rqst; 732 struct rpc_xprt *xprt = rep->rr_xprt; 733 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 734 __be32 *iptr; 735 int i, rdmalen, status; 736 737 /* Check status. If bad, signal disconnect and return rep to pool */ 738 if (rep->rr_len == ~0U) { 739 rpcrdma_recv_buffer_put(rep); 740 if (r_xprt->rx_ep.rep_connected == 1) { 741 r_xprt->rx_ep.rep_connected = -EIO; 742 rpcrdma_conn_func(&r_xprt->rx_ep); 743 } 744 return; 745 } 746 if (rep->rr_len < 28) { 747 dprintk("RPC: %s: short/invalid reply\n", __func__); 748 goto repost; 749 } 750 headerp = (struct rpcrdma_msg *) rep->rr_base; 751 if (headerp->rm_vers != xdr_one) { 752 dprintk("RPC: %s: invalid version %d\n", 753 __func__, ntohl(headerp->rm_vers)); 754 goto repost; 755 } 756 757 /* Get XID and try for a match. */ 758 spin_lock(&xprt->transport_lock); 759 rqst = xprt_lookup_rqst(xprt, headerp->rm_xid); 760 if (rqst == NULL) { 761 spin_unlock(&xprt->transport_lock); 762 dprintk("RPC: %s: reply 0x%p failed " 763 "to match any request xid 0x%08x len %d\n", 764 __func__, rep, headerp->rm_xid, rep->rr_len); 765repost: 766 r_xprt->rx_stats.bad_reply_count++; 767 rep->rr_func = rpcrdma_reply_handler; 768 if (rpcrdma_ep_post_recv(&r_xprt->rx_ia, &r_xprt->rx_ep, rep)) 769 rpcrdma_recv_buffer_put(rep); 770 771 return; 772 } 773 774 /* get request object */ 775 req = rpcr_to_rdmar(rqst); 776 777 dprintk("RPC: %s: reply 0x%p completes request 0x%p\n" 778 " RPC request 0x%p xid 0x%08x\n", 779 __func__, rep, req, rqst, headerp->rm_xid); 780 781 BUG_ON(!req || req->rl_reply); 782 783 /* from here on, the reply is no longer an orphan */ 784 req->rl_reply = rep; 785 786 /* check for expected message types */ 787 /* The order of some of these tests is important. */ 788 switch (headerp->rm_type) { 789 case htonl(RDMA_MSG): 790 /* never expect read chunks */ 791 /* never expect reply chunks (two ways to check) */ 792 /* never expect write chunks without having offered RDMA */ 793 if (headerp->rm_body.rm_chunks[0] != xdr_zero || 794 (headerp->rm_body.rm_chunks[1] == xdr_zero && 795 headerp->rm_body.rm_chunks[2] != xdr_zero) || 796 (headerp->rm_body.rm_chunks[1] != xdr_zero && 797 req->rl_nchunks == 0)) 798 goto badheader; 799 if (headerp->rm_body.rm_chunks[1] != xdr_zero) { 800 /* count any expected write chunks in read reply */ 801 /* start at write chunk array count */ 802 iptr = &headerp->rm_body.rm_chunks[2]; 803 rdmalen = rpcrdma_count_chunks(rep, 804 req->rl_nchunks, 1, &iptr); 805 /* check for validity, and no reply chunk after */ 806 if (rdmalen < 0 || *iptr++ != xdr_zero) 807 goto badheader; 808 rep->rr_len -= 809 ((unsigned char *)iptr - (unsigned char *)headerp); 810 status = rep->rr_len + rdmalen; 811 r_xprt->rx_stats.total_rdma_reply += rdmalen; 812 /* special case - last chunk may omit padding */ 813 if (rdmalen &= 3) { 814 rdmalen = 4 - rdmalen; 815 status += rdmalen; 816 } 817 } else { 818 /* else ordinary inline */ 819 rdmalen = 0; 820 iptr = (__be32 *)((unsigned char *)headerp + 28); 821 rep->rr_len -= 28; /*sizeof *headerp;*/ 822 status = rep->rr_len; 823 } 824 /* Fix up the rpc results for upper layer */ 825 rpcrdma_inline_fixup(rqst, (char *)iptr, rep->rr_len, rdmalen); 826 break; 827 828 case htonl(RDMA_NOMSG): 829 /* never expect read or write chunks, always reply chunks */ 830 if (headerp->rm_body.rm_chunks[0] != xdr_zero || 831 headerp->rm_body.rm_chunks[1] != xdr_zero || 832 headerp->rm_body.rm_chunks[2] != xdr_one || 833 req->rl_nchunks == 0) 834 goto badheader; 835 iptr = (__be32 *)((unsigned char *)headerp + 28); 836 rdmalen = rpcrdma_count_chunks(rep, req->rl_nchunks, 0, &iptr); 837 if (rdmalen < 0) 838 goto badheader; 839 r_xprt->rx_stats.total_rdma_reply += rdmalen; 840 /* Reply chunk buffer already is the reply vector - no fixup. */ 841 status = rdmalen; 842 break; 843 844badheader: 845 default: 846 dprintk("%s: invalid rpcrdma reply header (type %d):" 847 " chunks[012] == %d %d %d" 848 " expected chunks <= %d\n", 849 __func__, ntohl(headerp->rm_type), 850 headerp->rm_body.rm_chunks[0], 851 headerp->rm_body.rm_chunks[1], 852 headerp->rm_body.rm_chunks[2], 853 req->rl_nchunks); 854 status = -EIO; 855 r_xprt->rx_stats.bad_reply_count++; 856 break; 857 } 858 859 /* If using mw bind, start the deregister process now. */ 860 /* (Note: if mr_free(), cannot perform it here, in tasklet context) */ 861 if (req->rl_nchunks) switch (r_xprt->rx_ia.ri_memreg_strategy) { 862 case RPCRDMA_MEMWINDOWS: 863 for (i = 0; req->rl_nchunks-- > 1;) 864 i += rpcrdma_deregister_external( 865 &req->rl_segments[i], r_xprt, NULL); 866 /* Optionally wait (not here) for unbinds to complete */ 867 rep->rr_func = rpcrdma_unbind_func; 868 (void) rpcrdma_deregister_external(&req->rl_segments[i], 869 r_xprt, rep); 870 break; 871 case RPCRDMA_MEMWINDOWS_ASYNC: 872 for (i = 0; req->rl_nchunks--;) 873 i += rpcrdma_deregister_external(&req->rl_segments[i], 874 r_xprt, NULL); 875 break; 876 default: 877 break; 878 } 879 880 dprintk("RPC: %s: xprt_complete_rqst(0x%p, 0x%p, %d)\n", 881 __func__, xprt, rqst, status); 882 xprt_complete_rqst(rqst->rq_task, status); 883 spin_unlock(&xprt->transport_lock); 884} 885