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 56 #ifdef RPC_DEBUG 57 static const char transfertypes[][12] = { 58 "pure inline", /* no chunks */ 59 " read chunk", /* some argument via rdma read */ 60 "*read chunk", /* entire request via rdma read */ 61 "write chunk", /* some result via rdma write */ 62 "reply chunk" /* entire reply via rdma write */ 63 }; 64 #endif 65 66 /* 67 * Chunk assembly from upper layer xdr_buf. 68 * 69 * Prepare the passed-in xdr_buf into representation as RPC/RDMA chunk 70 * elements. Segments are then coalesced when registered, if possible 71 * within the selected memreg mode. 72 * 73 * Returns positive number of segments converted, or a negative errno. 74 */ 75 76 static int 77 rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos, 78 enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg, int nsegs) 79 { 80 int len, n = 0, p; 81 int page_base; 82 struct page **ppages; 83 84 if (pos == 0 && xdrbuf->head[0].iov_len) { 85 seg[n].mr_page = NULL; 86 seg[n].mr_offset = xdrbuf->head[0].iov_base; 87 seg[n].mr_len = xdrbuf->head[0].iov_len; 88 ++n; 89 } 90 91 len = xdrbuf->page_len; 92 ppages = xdrbuf->pages + (xdrbuf->page_base >> PAGE_SHIFT); 93 page_base = xdrbuf->page_base & ~PAGE_MASK; 94 p = 0; 95 while (len && n < nsegs) { 96 if (!ppages[p]) { 97 /* alloc the pagelist for receiving buffer */ 98 ppages[p] = alloc_page(GFP_ATOMIC); 99 if (!ppages[p]) 100 return -ENOMEM; 101 } 102 seg[n].mr_page = ppages[p]; 103 seg[n].mr_offset = (void *)(unsigned long) page_base; 104 seg[n].mr_len = min_t(u32, PAGE_SIZE - page_base, len); 105 if (seg[n].mr_len > PAGE_SIZE) 106 return -EIO; 107 len -= seg[n].mr_len; 108 ++n; 109 ++p; 110 page_base = 0; /* page offset only applies to first page */ 111 } 112 113 /* Message overflows the seg array */ 114 if (len && n == nsegs) 115 return -EIO; 116 117 if (xdrbuf->tail[0].iov_len) { 118 /* the rpcrdma protocol allows us to omit any trailing 119 * xdr pad bytes, saving the server an RDMA operation. */ 120 if (xdrbuf->tail[0].iov_len < 4 && xprt_rdma_pad_optimize) 121 return n; 122 if (n == nsegs) 123 /* Tail remains, but we're out of segments */ 124 return -EIO; 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 ++n; 129 } 130 131 return n; 132 } 133 134 /* 135 * Create read/write chunk lists, and reply chunks, for RDMA 136 * 137 * Assume check against THRESHOLD has been done, and chunks are required. 138 * Assume only encoding one list entry for read|write chunks. The NFSv3 139 * protocol is simple enough to allow this as it only has a single "bulk 140 * result" in each procedure - complicated NFSv4 COMPOUNDs are not. (The 141 * RDMA/Sessions NFSv4 proposal addresses this for future v4 revs.) 142 * 143 * When used for a single reply chunk (which is a special write 144 * chunk used for the entire reply, rather than just the data), it 145 * is used primarily for READDIR and READLINK which would otherwise 146 * be severely size-limited by a small rdma inline read max. The server 147 * response will come back as an RDMA Write, followed by a message 148 * of type RDMA_NOMSG carrying the xid and length. As a result, reply 149 * chunks do not provide data alignment, however they do not require 150 * "fixup" (moving the response to the upper layer buffer) either. 151 * 152 * Encoding key for single-list chunks (HLOO = Handle32 Length32 Offset64): 153 * 154 * Read chunklist (a linked list): 155 * N elements, position P (same P for all chunks of same arg!): 156 * 1 - PHLOO - 1 - PHLOO - ... - 1 - PHLOO - 0 157 * 158 * Write chunklist (a list of (one) counted array): 159 * N elements: 160 * 1 - N - HLOO - HLOO - ... - HLOO - 0 161 * 162 * Reply chunk (a counted array): 163 * N elements: 164 * 1 - N - HLOO - HLOO - ... - HLOO 165 * 166 * Returns positive RPC/RDMA header size, or negative errno. 167 */ 168 169 static ssize_t 170 rpcrdma_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_xprt); 175 int n, 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 nsegs; 203 204 do { 205 n = rpcrdma_register_external(seg, nsegs, 206 cur_wchunk != NULL, r_xprt); 207 if (n <= 0) 208 goto out; 209 if (cur_rchunk) { /* read */ 210 cur_rchunk->rc_discrim = xdr_one; 211 /* all read chunks have the same "position" */ 212 cur_rchunk->rc_position = htonl(pos); 213 cur_rchunk->rc_target.rs_handle = htonl(seg->mr_rkey); 214 cur_rchunk->rc_target.rs_length = htonl(seg->mr_len); 215 xdr_encode_hyper( 216 (__be32 *)&cur_rchunk->rc_target.rs_offset, 217 seg->mr_base); 218 dprintk("RPC: %s: read chunk " 219 "elem %d@0x%llx:0x%x pos %u (%s)\n", __func__, 220 seg->mr_len, (unsigned long long)seg->mr_base, 221 seg->mr_rkey, pos, n < nsegs ? "more" : "last"); 222 cur_rchunk++; 223 r_xprt->rx_stats.read_chunk_count++; 224 } else { /* write/reply */ 225 cur_wchunk->wc_target.rs_handle = htonl(seg->mr_rkey); 226 cur_wchunk->wc_target.rs_length = htonl(seg->mr_len); 227 xdr_encode_hyper( 228 (__be32 *)&cur_wchunk->wc_target.rs_offset, 229 seg->mr_base); 230 dprintk("RPC: %s: %s chunk " 231 "elem %d@0x%llx:0x%x (%s)\n", __func__, 232 (type == rpcrdma_replych) ? "reply" : "write", 233 seg->mr_len, (unsigned long long)seg->mr_base, 234 seg->mr_rkey, n < nsegs ? "more" : "last"); 235 cur_wchunk++; 236 if (type == rpcrdma_replych) 237 r_xprt->rx_stats.reply_chunk_count++; 238 else 239 r_xprt->rx_stats.write_chunk_count++; 240 r_xprt->rx_stats.total_rdma_request += seg->mr_len; 241 } 242 nchunks++; 243 seg += n; 244 nsegs -= n; 245 } while (nsegs); 246 247 /* success. all failures return above */ 248 req->rl_nchunks = nchunks; 249 250 /* 251 * finish off header. If write, marshal discrim and nchunks. 252 */ 253 if (cur_rchunk) { 254 iptr = (__be32 *) cur_rchunk; 255 *iptr++ = xdr_zero; /* finish the read chunk list */ 256 *iptr++ = xdr_zero; /* encode a NULL write chunk list */ 257 *iptr++ = xdr_zero; /* encode a NULL reply chunk */ 258 } else { 259 warray->wc_discrim = xdr_one; 260 warray->wc_nchunks = htonl(nchunks); 261 iptr = (__be32 *) cur_wchunk; 262 if (type == rpcrdma_writech) { 263 *iptr++ = xdr_zero; /* finish the write chunk list */ 264 *iptr++ = xdr_zero; /* encode a NULL reply chunk */ 265 } 266 } 267 268 /* 269 * Return header size. 270 */ 271 return (unsigned char *)iptr - (unsigned char *)headerp; 272 273 out: 274 if (r_xprt->rx_ia.ri_memreg_strategy != RPCRDMA_FRMR) { 275 for (pos = 0; nchunks--;) 276 pos += rpcrdma_deregister_external( 277 &req->rl_segments[pos], r_xprt); 278 } 279 return n; 280 } 281 282 /* 283 * Marshal chunks. This routine returns the header length 284 * consumed by marshaling. 285 * 286 * Returns positive RPC/RDMA header size, or negative errno. 287 */ 288 289 ssize_t 290 rpcrdma_marshal_chunks(struct rpc_rqst *rqst, ssize_t result) 291 { 292 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 293 struct rpcrdma_msg *headerp = (struct rpcrdma_msg *)req->rl_base; 294 295 if (req->rl_rtype != rpcrdma_noch) 296 result = rpcrdma_create_chunks(rqst, &rqst->rq_snd_buf, 297 headerp, req->rl_rtype); 298 else if (req->rl_wtype != rpcrdma_noch) 299 result = rpcrdma_create_chunks(rqst, &rqst->rq_rcv_buf, 300 headerp, req->rl_wtype); 301 return result; 302 } 303 304 /* 305 * Copy write data inline. 306 * This function is used for "small" requests. Data which is passed 307 * to RPC via iovecs (or page list) is copied directly into the 308 * pre-registered memory buffer for this request. For small amounts 309 * of data, this is efficient. The cutoff value is tunable. 310 */ 311 static int 312 rpcrdma_inline_pullup(struct rpc_rqst *rqst, int pad) 313 { 314 int i, npages, curlen; 315 int copy_len; 316 unsigned char *srcp, *destp; 317 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); 318 int page_base; 319 struct page **ppages; 320 321 destp = rqst->rq_svec[0].iov_base; 322 curlen = rqst->rq_svec[0].iov_len; 323 destp += curlen; 324 /* 325 * Do optional padding where it makes sense. Alignment of write 326 * payload can help the server, if our setting is accurate. 327 */ 328 pad -= (curlen + 36/*sizeof(struct rpcrdma_msg_padded)*/); 329 if (pad < 0 || rqst->rq_slen - curlen < RPCRDMA_INLINE_PAD_THRESH) 330 pad = 0; /* don't pad this request */ 331 332 dprintk("RPC: %s: pad %d destp 0x%p len %d hdrlen %d\n", 333 __func__, pad, destp, rqst->rq_slen, curlen); 334 335 copy_len = rqst->rq_snd_buf.page_len; 336 337 if (rqst->rq_snd_buf.tail[0].iov_len) { 338 curlen = rqst->rq_snd_buf.tail[0].iov_len; 339 if (destp + copy_len != rqst->rq_snd_buf.tail[0].iov_base) { 340 memmove(destp + copy_len, 341 rqst->rq_snd_buf.tail[0].iov_base, curlen); 342 r_xprt->rx_stats.pullup_copy_count += curlen; 343 } 344 dprintk("RPC: %s: tail destp 0x%p len %d\n", 345 __func__, destp + copy_len, curlen); 346 rqst->rq_svec[0].iov_len += curlen; 347 } 348 r_xprt->rx_stats.pullup_copy_count += copy_len; 349 350 page_base = rqst->rq_snd_buf.page_base; 351 ppages = rqst->rq_snd_buf.pages + (page_base >> PAGE_SHIFT); 352 page_base &= ~PAGE_MASK; 353 npages = PAGE_ALIGN(page_base+copy_len) >> PAGE_SHIFT; 354 for (i = 0; copy_len && i < npages; i++) { 355 curlen = PAGE_SIZE - page_base; 356 if (curlen > copy_len) 357 curlen = copy_len; 358 dprintk("RPC: %s: page %d destp 0x%p len %d curlen %d\n", 359 __func__, i, destp, copy_len, curlen); 360 srcp = kmap_atomic(ppages[i]); 361 memcpy(destp, srcp+page_base, curlen); 362 kunmap_atomic(srcp); 363 rqst->rq_svec[0].iov_len += curlen; 364 destp += curlen; 365 copy_len -= curlen; 366 page_base = 0; 367 } 368 /* header now contains entire send message */ 369 return pad; 370 } 371 372 /* 373 * Marshal a request: the primary job of this routine is to choose 374 * the transfer modes. See comments below. 375 * 376 * Uses multiple RDMA IOVs for a request: 377 * [0] -- RPC RDMA header, which uses memory from the *start* of the 378 * preregistered buffer that already holds the RPC data in 379 * its middle. 380 * [1] -- the RPC header/data, marshaled by RPC and the NFS protocol. 381 * [2] -- optional padding. 382 * [3] -- if padded, header only in [1] and data here. 383 * 384 * Returns zero on success, otherwise a negative errno. 385 */ 386 387 int 388 rpcrdma_marshal_req(struct rpc_rqst *rqst) 389 { 390 struct rpc_xprt *xprt = rqst->rq_xprt; 391 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 392 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 393 char *base; 394 size_t rpclen, padlen; 395 ssize_t hdrlen; 396 struct rpcrdma_msg *headerp; 397 398 /* 399 * rpclen gets amount of data in first buffer, which is the 400 * pre-registered buffer. 401 */ 402 base = rqst->rq_svec[0].iov_base; 403 rpclen = rqst->rq_svec[0].iov_len; 404 405 /* build RDMA header in private area at front */ 406 headerp = (struct rpcrdma_msg *) req->rl_base; 407 /* don't htonl XID, it's already done in request */ 408 headerp->rm_xid = rqst->rq_xid; 409 headerp->rm_vers = xdr_one; 410 headerp->rm_credit = htonl(r_xprt->rx_buf.rb_max_requests); 411 headerp->rm_type = htonl(RDMA_MSG); 412 413 /* 414 * Chunks needed for results? 415 * 416 * o If the expected result is under the inline threshold, all ops 417 * return as inline (but see later). 418 * o Large non-read ops return as a single reply chunk. 419 * o Large read ops return data as write chunk(s), header as inline. 420 * 421 * Note: the NFS code sending down multiple result segments implies 422 * the op is one of read, readdir[plus], readlink or NFSv4 getacl. 423 */ 424 425 /* 426 * This code can handle read chunks, write chunks OR reply 427 * chunks -- only one type. If the request is too big to fit 428 * inline, then we will choose read chunks. If the request is 429 * a READ, then use write chunks to separate the file data 430 * into pages; otherwise use reply chunks. 431 */ 432 if (rqst->rq_rcv_buf.buflen <= RPCRDMA_INLINE_READ_THRESHOLD(rqst)) 433 req->rl_wtype = rpcrdma_noch; 434 else if (rqst->rq_rcv_buf.page_len == 0) 435 req->rl_wtype = rpcrdma_replych; 436 else if (rqst->rq_rcv_buf.flags & XDRBUF_READ) 437 req->rl_wtype = rpcrdma_writech; 438 else 439 req->rl_wtype = rpcrdma_replych; 440 441 /* 442 * Chunks needed for arguments? 443 * 444 * o If the total request is under the inline threshold, all ops 445 * are sent as inline. 446 * o Large non-write ops are sent with the entire message as a 447 * single read chunk (protocol 0-position special case). 448 * o Large write ops transmit data as read chunk(s), header as 449 * inline. 450 * 451 * Note: the NFS code sending down multiple argument segments 452 * implies the op is a write. 453 * TBD check NFSv4 setacl 454 */ 455 if (rqst->rq_snd_buf.len <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst)) 456 req->rl_rtype = rpcrdma_noch; 457 else if (rqst->rq_snd_buf.page_len == 0) 458 req->rl_rtype = rpcrdma_areadch; 459 else 460 req->rl_rtype = rpcrdma_readch; 461 462 /* The following simplification is not true forever */ 463 if (req->rl_rtype != rpcrdma_noch && req->rl_wtype == rpcrdma_replych) 464 req->rl_wtype = rpcrdma_noch; 465 if (req->rl_rtype != rpcrdma_noch && req->rl_wtype != rpcrdma_noch) { 466 dprintk("RPC: %s: cannot marshal multiple chunk lists\n", 467 __func__); 468 return -EIO; 469 } 470 471 hdrlen = 28; /*sizeof *headerp;*/ 472 padlen = 0; 473 474 /* 475 * Pull up any extra send data into the preregistered buffer. 476 * When padding is in use and applies to the transfer, insert 477 * it and change the message type. 478 */ 479 if (req->rl_rtype == rpcrdma_noch) { 480 481 padlen = rpcrdma_inline_pullup(rqst, 482 RPCRDMA_INLINE_PAD_VALUE(rqst)); 483 484 if (padlen) { 485 headerp->rm_type = htonl(RDMA_MSGP); 486 headerp->rm_body.rm_padded.rm_align = 487 htonl(RPCRDMA_INLINE_PAD_VALUE(rqst)); 488 headerp->rm_body.rm_padded.rm_thresh = 489 htonl(RPCRDMA_INLINE_PAD_THRESH); 490 headerp->rm_body.rm_padded.rm_pempty[0] = xdr_zero; 491 headerp->rm_body.rm_padded.rm_pempty[1] = xdr_zero; 492 headerp->rm_body.rm_padded.rm_pempty[2] = xdr_zero; 493 hdrlen += 2 * sizeof(u32); /* extra words in padhdr */ 494 if (req->rl_wtype != rpcrdma_noch) { 495 dprintk("RPC: %s: invalid chunk list\n", 496 __func__); 497 return -EIO; 498 } 499 } else { 500 headerp->rm_body.rm_nochunks.rm_empty[0] = xdr_zero; 501 headerp->rm_body.rm_nochunks.rm_empty[1] = xdr_zero; 502 headerp->rm_body.rm_nochunks.rm_empty[2] = xdr_zero; 503 /* new length after pullup */ 504 rpclen = rqst->rq_svec[0].iov_len; 505 /* 506 * Currently we try to not actually use read inline. 507 * Reply chunks have the desirable property that 508 * they land, packed, directly in the target buffers 509 * without headers, so they require no fixup. The 510 * additional RDMA Write op sends the same amount 511 * of data, streams on-the-wire and adds no overhead 512 * on receive. Therefore, we request a reply chunk 513 * for non-writes wherever feasible and efficient. 514 */ 515 if (req->rl_wtype == rpcrdma_noch) 516 req->rl_wtype = rpcrdma_replych; 517 } 518 } 519 520 hdrlen = rpcrdma_marshal_chunks(rqst, hdrlen); 521 if (hdrlen < 0) 522 return hdrlen; 523 524 dprintk("RPC: %s: %s: hdrlen %zd rpclen %zd padlen %zd" 525 " headerp 0x%p base 0x%p lkey 0x%x\n", 526 __func__, transfertypes[req->rl_wtype], hdrlen, rpclen, padlen, 527 headerp, base, req->rl_iov.lkey); 528 529 /* 530 * initialize send_iov's - normally only two: rdma chunk header and 531 * single preregistered RPC header buffer, but if padding is present, 532 * then use a preregistered (and zeroed) pad buffer between the RPC 533 * header and any write data. In all non-rdma cases, any following 534 * data has been copied into the RPC header buffer. 535 */ 536 req->rl_send_iov[0].addr = req->rl_iov.addr; 537 req->rl_send_iov[0].length = hdrlen; 538 req->rl_send_iov[0].lkey = req->rl_iov.lkey; 539 540 req->rl_send_iov[1].addr = req->rl_iov.addr + (base - req->rl_base); 541 req->rl_send_iov[1].length = rpclen; 542 req->rl_send_iov[1].lkey = req->rl_iov.lkey; 543 544 req->rl_niovs = 2; 545 546 if (padlen) { 547 struct rpcrdma_ep *ep = &r_xprt->rx_ep; 548 549 req->rl_send_iov[2].addr = ep->rep_pad.addr; 550 req->rl_send_iov[2].length = padlen; 551 req->rl_send_iov[2].lkey = ep->rep_pad.lkey; 552 553 req->rl_send_iov[3].addr = req->rl_send_iov[1].addr + rpclen; 554 req->rl_send_iov[3].length = rqst->rq_slen - rpclen; 555 req->rl_send_iov[3].lkey = req->rl_iov.lkey; 556 557 req->rl_niovs = 4; 558 } 559 560 return 0; 561 } 562 563 /* 564 * Chase down a received write or reply chunklist to get length 565 * RDMA'd by server. See map at rpcrdma_create_chunks()! :-) 566 */ 567 static int 568 rpcrdma_count_chunks(struct rpcrdma_rep *rep, unsigned int max, int wrchunk, __be32 **iptrp) 569 { 570 unsigned int i, total_len; 571 struct rpcrdma_write_chunk *cur_wchunk; 572 573 i = ntohl(**iptrp); /* get array count */ 574 if (i > max) 575 return -1; 576 cur_wchunk = (struct rpcrdma_write_chunk *) (*iptrp + 1); 577 total_len = 0; 578 while (i--) { 579 struct rpcrdma_segment *seg = &cur_wchunk->wc_target; 580 ifdebug(FACILITY) { 581 u64 off; 582 xdr_decode_hyper((__be32 *)&seg->rs_offset, &off); 583 dprintk("RPC: %s: chunk %d@0x%llx:0x%x\n", 584 __func__, 585 ntohl(seg->rs_length), 586 (unsigned long long)off, 587 ntohl(seg->rs_handle)); 588 } 589 total_len += ntohl(seg->rs_length); 590 ++cur_wchunk; 591 } 592 /* check and adjust for properly terminated write chunk */ 593 if (wrchunk) { 594 __be32 *w = (__be32 *) cur_wchunk; 595 if (*w++ != xdr_zero) 596 return -1; 597 cur_wchunk = (struct rpcrdma_write_chunk *) w; 598 } 599 if ((char *) cur_wchunk > rep->rr_base + rep->rr_len) 600 return -1; 601 602 *iptrp = (__be32 *) cur_wchunk; 603 return total_len; 604 } 605 606 /* 607 * Scatter inline received data back into provided iov's. 608 */ 609 static void 610 rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad) 611 { 612 int i, npages, curlen, olen; 613 char *destp; 614 struct page **ppages; 615 int page_base; 616 617 curlen = rqst->rq_rcv_buf.head[0].iov_len; 618 if (curlen > copy_len) { /* write chunk header fixup */ 619 curlen = copy_len; 620 rqst->rq_rcv_buf.head[0].iov_len = curlen; 621 } 622 623 dprintk("RPC: %s: srcp 0x%p len %d hdrlen %d\n", 624 __func__, srcp, copy_len, curlen); 625 626 /* Shift pointer for first receive segment only */ 627 rqst->rq_rcv_buf.head[0].iov_base = srcp; 628 srcp += curlen; 629 copy_len -= curlen; 630 631 olen = copy_len; 632 i = 0; 633 rpcx_to_rdmax(rqst->rq_xprt)->rx_stats.fixup_copy_count += olen; 634 page_base = rqst->rq_rcv_buf.page_base; 635 ppages = rqst->rq_rcv_buf.pages + (page_base >> PAGE_SHIFT); 636 page_base &= ~PAGE_MASK; 637 638 if (copy_len && rqst->rq_rcv_buf.page_len) { 639 npages = PAGE_ALIGN(page_base + 640 rqst->rq_rcv_buf.page_len) >> PAGE_SHIFT; 641 for (; i < npages; i++) { 642 curlen = PAGE_SIZE - page_base; 643 if (curlen > copy_len) 644 curlen = copy_len; 645 dprintk("RPC: %s: page %d" 646 " srcp 0x%p len %d curlen %d\n", 647 __func__, i, srcp, copy_len, curlen); 648 destp = kmap_atomic(ppages[i]); 649 memcpy(destp + page_base, srcp, curlen); 650 flush_dcache_page(ppages[i]); 651 kunmap_atomic(destp); 652 srcp += curlen; 653 copy_len -= curlen; 654 if (copy_len == 0) 655 break; 656 page_base = 0; 657 } 658 } 659 660 if (copy_len && rqst->rq_rcv_buf.tail[0].iov_len) { 661 curlen = copy_len; 662 if (curlen > rqst->rq_rcv_buf.tail[0].iov_len) 663 curlen = rqst->rq_rcv_buf.tail[0].iov_len; 664 if (rqst->rq_rcv_buf.tail[0].iov_base != srcp) 665 memmove(rqst->rq_rcv_buf.tail[0].iov_base, srcp, curlen); 666 dprintk("RPC: %s: tail srcp 0x%p len %d curlen %d\n", 667 __func__, srcp, copy_len, curlen); 668 rqst->rq_rcv_buf.tail[0].iov_len = curlen; 669 copy_len -= curlen; ++i; 670 } else 671 rqst->rq_rcv_buf.tail[0].iov_len = 0; 672 673 if (pad) { 674 /* implicit padding on terminal chunk */ 675 unsigned char *p = rqst->rq_rcv_buf.tail[0].iov_base; 676 while (pad--) 677 p[rqst->rq_rcv_buf.tail[0].iov_len++] = 0; 678 } 679 680 if (copy_len) 681 dprintk("RPC: %s: %d bytes in" 682 " %d extra segments (%d lost)\n", 683 __func__, olen, i, copy_len); 684 685 /* TBD avoid a warning from call_decode() */ 686 rqst->rq_private_buf = rqst->rq_rcv_buf; 687 } 688 689 void 690 rpcrdma_connect_worker(struct work_struct *work) 691 { 692 struct rpcrdma_ep *ep = 693 container_of(work, struct rpcrdma_ep, rep_connect_worker.work); 694 struct rpc_xprt *xprt = ep->rep_xprt; 695 696 spin_lock_bh(&xprt->transport_lock); 697 if (++xprt->connect_cookie == 0) /* maintain a reserved value */ 698 ++xprt->connect_cookie; 699 if (ep->rep_connected > 0) { 700 if (!xprt_test_and_set_connected(xprt)) 701 xprt_wake_pending_tasks(xprt, 0); 702 } else { 703 if (xprt_test_and_clear_connected(xprt)) 704 xprt_wake_pending_tasks(xprt, -ENOTCONN); 705 } 706 spin_unlock_bh(&xprt->transport_lock); 707 } 708 709 /* 710 * This function is called when an async event is posted to 711 * the connection which changes the connection state. All it 712 * does at this point is mark the connection up/down, the rpc 713 * timers do the rest. 714 */ 715 void 716 rpcrdma_conn_func(struct rpcrdma_ep *ep) 717 { 718 schedule_delayed_work(&ep->rep_connect_worker, 0); 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 */ 726 void 727 rpcrdma_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 rdmalen, status; 736 unsigned long cwnd; 737 738 /* Check status. If bad, signal disconnect and return rep to pool */ 739 if (rep->rr_len == ~0U) { 740 rpcrdma_recv_buffer_put(rep); 741 if (r_xprt->rx_ep.rep_connected == 1) { 742 r_xprt->rx_ep.rep_connected = -EIO; 743 rpcrdma_conn_func(&r_xprt->rx_ep); 744 } 745 return; 746 } 747 if (rep->rr_len < 28) { 748 dprintk("RPC: %s: short/invalid reply\n", __func__); 749 goto repost; 750 } 751 headerp = (struct rpcrdma_msg *) rep->rr_base; 752 if (headerp->rm_vers != xdr_one) { 753 dprintk("RPC: %s: invalid version %d\n", 754 __func__, ntohl(headerp->rm_vers)); 755 goto repost; 756 } 757 758 /* Get XID and try for a match. */ 759 spin_lock(&xprt->transport_lock); 760 rqst = xprt_lookup_rqst(xprt, headerp->rm_xid); 761 if (rqst == NULL) { 762 spin_unlock(&xprt->transport_lock); 763 dprintk("RPC: %s: reply 0x%p failed " 764 "to match any request xid 0x%08x len %d\n", 765 __func__, rep, headerp->rm_xid, rep->rr_len); 766 repost: 767 r_xprt->rx_stats.bad_reply_count++; 768 rep->rr_func = rpcrdma_reply_handler; 769 if (rpcrdma_ep_post_recv(&r_xprt->rx_ia, &r_xprt->rx_ep, rep)) 770 rpcrdma_recv_buffer_put(rep); 771 772 return; 773 } 774 775 /* get request object */ 776 req = rpcr_to_rdmar(rqst); 777 if (req->rl_reply) { 778 spin_unlock(&xprt->transport_lock); 779 dprintk("RPC: %s: duplicate reply 0x%p to RPC " 780 "request 0x%p: xid 0x%08x\n", __func__, rep, req, 781 headerp->rm_xid); 782 goto repost; 783 } 784 785 dprintk("RPC: %s: reply 0x%p completes request 0x%p\n" 786 " RPC request 0x%p xid 0x%08x\n", 787 __func__, rep, req, rqst, headerp->rm_xid); 788 789 /* from here on, the reply is no longer an orphan */ 790 req->rl_reply = rep; 791 xprt->reestablish_timeout = 0; 792 793 /* check for expected message types */ 794 /* The order of some of these tests is important. */ 795 switch (headerp->rm_type) { 796 case htonl(RDMA_MSG): 797 /* never expect read chunks */ 798 /* never expect reply chunks (two ways to check) */ 799 /* never expect write chunks without having offered RDMA */ 800 if (headerp->rm_body.rm_chunks[0] != xdr_zero || 801 (headerp->rm_body.rm_chunks[1] == xdr_zero && 802 headerp->rm_body.rm_chunks[2] != xdr_zero) || 803 (headerp->rm_body.rm_chunks[1] != xdr_zero && 804 req->rl_nchunks == 0)) 805 goto badheader; 806 if (headerp->rm_body.rm_chunks[1] != xdr_zero) { 807 /* count any expected write chunks in read reply */ 808 /* start at write chunk array count */ 809 iptr = &headerp->rm_body.rm_chunks[2]; 810 rdmalen = rpcrdma_count_chunks(rep, 811 req->rl_nchunks, 1, &iptr); 812 /* check for validity, and no reply chunk after */ 813 if (rdmalen < 0 || *iptr++ != xdr_zero) 814 goto badheader; 815 rep->rr_len -= 816 ((unsigned char *)iptr - (unsigned char *)headerp); 817 status = rep->rr_len + rdmalen; 818 r_xprt->rx_stats.total_rdma_reply += rdmalen; 819 /* special case - last chunk may omit padding */ 820 if (rdmalen &= 3) { 821 rdmalen = 4 - rdmalen; 822 status += rdmalen; 823 } 824 } else { 825 /* else ordinary inline */ 826 rdmalen = 0; 827 iptr = (__be32 *)((unsigned char *)headerp + 28); 828 rep->rr_len -= 28; /*sizeof *headerp;*/ 829 status = rep->rr_len; 830 } 831 /* Fix up the rpc results for upper layer */ 832 rpcrdma_inline_fixup(rqst, (char *)iptr, rep->rr_len, rdmalen); 833 break; 834 835 case htonl(RDMA_NOMSG): 836 /* never expect read or write chunks, always reply chunks */ 837 if (headerp->rm_body.rm_chunks[0] != xdr_zero || 838 headerp->rm_body.rm_chunks[1] != xdr_zero || 839 headerp->rm_body.rm_chunks[2] != xdr_one || 840 req->rl_nchunks == 0) 841 goto badheader; 842 iptr = (__be32 *)((unsigned char *)headerp + 28); 843 rdmalen = rpcrdma_count_chunks(rep, req->rl_nchunks, 0, &iptr); 844 if (rdmalen < 0) 845 goto badheader; 846 r_xprt->rx_stats.total_rdma_reply += rdmalen; 847 /* Reply chunk buffer already is the reply vector - no fixup. */ 848 status = rdmalen; 849 break; 850 851 badheader: 852 default: 853 dprintk("%s: invalid rpcrdma reply header (type %d):" 854 " chunks[012] == %d %d %d" 855 " expected chunks <= %d\n", 856 __func__, ntohl(headerp->rm_type), 857 headerp->rm_body.rm_chunks[0], 858 headerp->rm_body.rm_chunks[1], 859 headerp->rm_body.rm_chunks[2], 860 req->rl_nchunks); 861 status = -EIO; 862 r_xprt->rx_stats.bad_reply_count++; 863 break; 864 } 865 866 cwnd = xprt->cwnd; 867 xprt->cwnd = atomic_read(&r_xprt->rx_buf.rb_credits) << RPC_CWNDSHIFT; 868 if (xprt->cwnd > cwnd) 869 xprt_release_rqst_cong(rqst->rq_task); 870 871 dprintk("RPC: %s: xprt_complete_rqst(0x%p, 0x%p, %d)\n", 872 __func__, xprt, rqst, status); 873 xprt_complete_rqst(rqst->rq_task, status); 874 spin_unlock(&xprt->transport_lock); 875 } 876