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 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 53 # define RPCDBG_FACILITY RPCDBG_TRANS 54 #endif 55 56 enum rpcrdma_chunktype { 57 rpcrdma_noch = 0, 58 rpcrdma_readch, 59 rpcrdma_areadch, 60 rpcrdma_writech, 61 rpcrdma_replych 62 }; 63 64 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 65 static 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 * Returns positive number of segments converted, or a negative errno. 82 */ 83 84 static int 85 rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos, 86 enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg, int nsegs) 87 { 88 int len, n = 0, p; 89 int page_base; 90 struct page **ppages; 91 92 if (pos == 0 && xdrbuf->head[0].iov_len) { 93 seg[n].mr_page = NULL; 94 seg[n].mr_offset = xdrbuf->head[0].iov_base; 95 seg[n].mr_len = xdrbuf->head[0].iov_len; 96 ++n; 97 } 98 99 len = xdrbuf->page_len; 100 ppages = xdrbuf->pages + (xdrbuf->page_base >> PAGE_SHIFT); 101 page_base = xdrbuf->page_base & ~PAGE_MASK; 102 p = 0; 103 while (len && n < nsegs) { 104 if (!ppages[p]) { 105 /* alloc the pagelist for receiving buffer */ 106 ppages[p] = alloc_page(GFP_ATOMIC); 107 if (!ppages[p]) 108 return -ENOMEM; 109 } 110 seg[n].mr_page = ppages[p]; 111 seg[n].mr_offset = (void *)(unsigned long) page_base; 112 seg[n].mr_len = min_t(u32, PAGE_SIZE - page_base, len); 113 if (seg[n].mr_len > PAGE_SIZE) 114 return -EIO; 115 len -= seg[n].mr_len; 116 ++n; 117 ++p; 118 page_base = 0; /* page offset only applies to first page */ 119 } 120 121 /* Message overflows the seg array */ 122 if (len && n == nsegs) 123 return -EIO; 124 125 if (xdrbuf->tail[0].iov_len) { 126 /* the rpcrdma protocol allows us to omit any trailing 127 * xdr pad bytes, saving the server an RDMA operation. */ 128 if (xdrbuf->tail[0].iov_len < 4 && xprt_rdma_pad_optimize) 129 return n; 130 if (n == nsegs) 131 /* Tail remains, but we're out of segments */ 132 return -EIO; 133 seg[n].mr_page = NULL; 134 seg[n].mr_offset = xdrbuf->tail[0].iov_base; 135 seg[n].mr_len = xdrbuf->tail[0].iov_len; 136 ++n; 137 } 138 139 return n; 140 } 141 142 /* 143 * Create read/write chunk lists, and reply chunks, for RDMA 144 * 145 * Assume check against THRESHOLD has been done, and chunks are required. 146 * Assume only encoding one list entry for read|write chunks. The NFSv3 147 * protocol is simple enough to allow this as it only has a single "bulk 148 * result" in each procedure - complicated NFSv4 COMPOUNDs are not. (The 149 * RDMA/Sessions NFSv4 proposal addresses this for future v4 revs.) 150 * 151 * When used for a single reply chunk (which is a special write 152 * chunk used for the entire reply, rather than just the data), it 153 * is used primarily for READDIR and READLINK which would otherwise 154 * be severely size-limited by a small rdma inline read max. The server 155 * response will come back as an RDMA Write, followed by a message 156 * of type RDMA_NOMSG carrying the xid and length. As a result, reply 157 * chunks do not provide data alignment, however they do not require 158 * "fixup" (moving the response to the upper layer buffer) either. 159 * 160 * Encoding key for single-list chunks (HLOO = Handle32 Length32 Offset64): 161 * 162 * Read chunklist (a linked list): 163 * N elements, position P (same P for all chunks of same arg!): 164 * 1 - PHLOO - 1 - PHLOO - ... - 1 - PHLOO - 0 165 * 166 * Write chunklist (a list of (one) counted array): 167 * N elements: 168 * 1 - N - HLOO - HLOO - ... - HLOO - 0 169 * 170 * Reply chunk (a counted array): 171 * N elements: 172 * 1 - N - HLOO - HLOO - ... - HLOO 173 * 174 * Returns positive RPC/RDMA header size, or negative errno. 175 */ 176 177 static ssize_t 178 rpcrdma_create_chunks(struct rpc_rqst *rqst, struct xdr_buf *target, 179 struct rpcrdma_msg *headerp, enum rpcrdma_chunktype type) 180 { 181 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 182 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); 183 int n, nsegs, nchunks = 0; 184 unsigned int pos; 185 struct rpcrdma_mr_seg *seg = req->rl_segments; 186 struct rpcrdma_read_chunk *cur_rchunk = NULL; 187 struct rpcrdma_write_array *warray = NULL; 188 struct rpcrdma_write_chunk *cur_wchunk = NULL; 189 __be32 *iptr = headerp->rm_body.rm_chunks; 190 int (*map)(struct rpcrdma_xprt *, struct rpcrdma_mr_seg *, int, bool); 191 192 if (type == rpcrdma_readch || type == rpcrdma_areadch) { 193 /* a read chunk - server will RDMA Read our memory */ 194 cur_rchunk = (struct rpcrdma_read_chunk *) iptr; 195 } else { 196 /* a write or reply chunk - server will RDMA Write our memory */ 197 *iptr++ = xdr_zero; /* encode a NULL read chunk list */ 198 if (type == rpcrdma_replych) 199 *iptr++ = xdr_zero; /* a NULL write chunk list */ 200 warray = (struct rpcrdma_write_array *) iptr; 201 cur_wchunk = (struct rpcrdma_write_chunk *) (warray + 1); 202 } 203 204 if (type == rpcrdma_replych || type == rpcrdma_areadch) 205 pos = 0; 206 else 207 pos = target->head[0].iov_len; 208 209 nsegs = rpcrdma_convert_iovs(target, pos, type, seg, RPCRDMA_MAX_SEGS); 210 if (nsegs < 0) 211 return nsegs; 212 213 map = r_xprt->rx_ia.ri_ops->ro_map; 214 do { 215 n = map(r_xprt, seg, nsegs, cur_wchunk != NULL); 216 if (n <= 0) 217 goto out; 218 if (cur_rchunk) { /* read */ 219 cur_rchunk->rc_discrim = xdr_one; 220 /* all read chunks have the same "position" */ 221 cur_rchunk->rc_position = cpu_to_be32(pos); 222 cur_rchunk->rc_target.rs_handle = 223 cpu_to_be32(seg->mr_rkey); 224 cur_rchunk->rc_target.rs_length = 225 cpu_to_be32(seg->mr_len); 226 xdr_encode_hyper( 227 (__be32 *)&cur_rchunk->rc_target.rs_offset, 228 seg->mr_base); 229 dprintk("RPC: %s: read chunk " 230 "elem %d@0x%llx:0x%x pos %u (%s)\n", __func__, 231 seg->mr_len, (unsigned long long)seg->mr_base, 232 seg->mr_rkey, pos, n < nsegs ? "more" : "last"); 233 cur_rchunk++; 234 r_xprt->rx_stats.read_chunk_count++; 235 } else { /* write/reply */ 236 cur_wchunk->wc_target.rs_handle = 237 cpu_to_be32(seg->mr_rkey); 238 cur_wchunk->wc_target.rs_length = 239 cpu_to_be32(seg->mr_len); 240 xdr_encode_hyper( 241 (__be32 *)&cur_wchunk->wc_target.rs_offset, 242 seg->mr_base); 243 dprintk("RPC: %s: %s chunk " 244 "elem %d@0x%llx:0x%x (%s)\n", __func__, 245 (type == rpcrdma_replych) ? "reply" : "write", 246 seg->mr_len, (unsigned long long)seg->mr_base, 247 seg->mr_rkey, n < nsegs ? "more" : "last"); 248 cur_wchunk++; 249 if (type == rpcrdma_replych) 250 r_xprt->rx_stats.reply_chunk_count++; 251 else 252 r_xprt->rx_stats.write_chunk_count++; 253 r_xprt->rx_stats.total_rdma_request += seg->mr_len; 254 } 255 nchunks++; 256 seg += n; 257 nsegs -= n; 258 } while (nsegs); 259 260 /* success. all failures return above */ 261 req->rl_nchunks = nchunks; 262 263 /* 264 * finish off header. If write, marshal discrim and nchunks. 265 */ 266 if (cur_rchunk) { 267 iptr = (__be32 *) cur_rchunk; 268 *iptr++ = xdr_zero; /* finish the read chunk list */ 269 *iptr++ = xdr_zero; /* encode a NULL write chunk list */ 270 *iptr++ = xdr_zero; /* encode a NULL reply chunk */ 271 } else { 272 warray->wc_discrim = xdr_one; 273 warray->wc_nchunks = cpu_to_be32(nchunks); 274 iptr = (__be32 *) cur_wchunk; 275 if (type == rpcrdma_writech) { 276 *iptr++ = xdr_zero; /* finish the write chunk list */ 277 *iptr++ = xdr_zero; /* encode a NULL reply chunk */ 278 } 279 } 280 281 /* 282 * Return header size. 283 */ 284 return (unsigned char *)iptr - (unsigned char *)headerp; 285 286 out: 287 for (pos = 0; nchunks--;) 288 pos += r_xprt->rx_ia.ri_ops->ro_unmap(r_xprt, 289 &req->rl_segments[pos]); 290 return n; 291 } 292 293 /* 294 * Copy write data inline. 295 * This function is used for "small" requests. Data which is passed 296 * to RPC via iovecs (or page list) is copied directly into the 297 * pre-registered memory buffer for this request. For small amounts 298 * of data, this is efficient. The cutoff value is tunable. 299 */ 300 static int 301 rpcrdma_inline_pullup(struct rpc_rqst *rqst, int pad) 302 { 303 int i, npages, curlen; 304 int copy_len; 305 unsigned char *srcp, *destp; 306 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(rqst->rq_xprt); 307 int page_base; 308 struct page **ppages; 309 310 destp = rqst->rq_svec[0].iov_base; 311 curlen = rqst->rq_svec[0].iov_len; 312 destp += curlen; 313 /* 314 * Do optional padding where it makes sense. Alignment of write 315 * payload can help the server, if our setting is accurate. 316 */ 317 pad -= (curlen + 36/*sizeof(struct rpcrdma_msg_padded)*/); 318 if (pad < 0 || rqst->rq_slen - curlen < RPCRDMA_INLINE_PAD_THRESH) 319 pad = 0; /* don't pad this request */ 320 321 dprintk("RPC: %s: pad %d destp 0x%p len %d hdrlen %d\n", 322 __func__, pad, destp, rqst->rq_slen, curlen); 323 324 copy_len = rqst->rq_snd_buf.page_len; 325 326 if (rqst->rq_snd_buf.tail[0].iov_len) { 327 curlen = rqst->rq_snd_buf.tail[0].iov_len; 328 if (destp + copy_len != rqst->rq_snd_buf.tail[0].iov_base) { 329 memmove(destp + copy_len, 330 rqst->rq_snd_buf.tail[0].iov_base, curlen); 331 r_xprt->rx_stats.pullup_copy_count += curlen; 332 } 333 dprintk("RPC: %s: tail destp 0x%p len %d\n", 334 __func__, destp + copy_len, curlen); 335 rqst->rq_svec[0].iov_len += curlen; 336 } 337 r_xprt->rx_stats.pullup_copy_count += copy_len; 338 339 page_base = rqst->rq_snd_buf.page_base; 340 ppages = rqst->rq_snd_buf.pages + (page_base >> PAGE_SHIFT); 341 page_base &= ~PAGE_MASK; 342 npages = PAGE_ALIGN(page_base+copy_len) >> PAGE_SHIFT; 343 for (i = 0; copy_len && i < npages; i++) { 344 curlen = PAGE_SIZE - page_base; 345 if (curlen > copy_len) 346 curlen = copy_len; 347 dprintk("RPC: %s: page %d destp 0x%p len %d curlen %d\n", 348 __func__, i, destp, copy_len, curlen); 349 srcp = kmap_atomic(ppages[i]); 350 memcpy(destp, srcp+page_base, curlen); 351 kunmap_atomic(srcp); 352 rqst->rq_svec[0].iov_len += curlen; 353 destp += curlen; 354 copy_len -= curlen; 355 page_base = 0; 356 } 357 /* header now contains entire send message */ 358 return pad; 359 } 360 361 /* 362 * Marshal a request: the primary job of this routine is to choose 363 * the transfer modes. See comments below. 364 * 365 * Uses multiple RDMA IOVs for a request: 366 * [0] -- RPC RDMA header, which uses memory from the *start* of the 367 * preregistered buffer that already holds the RPC data in 368 * its middle. 369 * [1] -- the RPC header/data, marshaled by RPC and the NFS protocol. 370 * [2] -- optional padding. 371 * [3] -- if padded, header only in [1] and data here. 372 * 373 * Returns zero on success, otherwise a negative errno. 374 */ 375 376 int 377 rpcrdma_marshal_req(struct rpc_rqst *rqst) 378 { 379 struct rpc_xprt *xprt = rqst->rq_xprt; 380 struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); 381 struct rpcrdma_req *req = rpcr_to_rdmar(rqst); 382 char *base; 383 size_t rpclen, padlen; 384 ssize_t hdrlen; 385 enum rpcrdma_chunktype rtype, wtype; 386 struct rpcrdma_msg *headerp; 387 388 /* 389 * rpclen gets amount of data in first buffer, which is the 390 * pre-registered buffer. 391 */ 392 base = rqst->rq_svec[0].iov_base; 393 rpclen = rqst->rq_svec[0].iov_len; 394 395 headerp = rdmab_to_msg(req->rl_rdmabuf); 396 /* don't byte-swap XID, it's already done in request */ 397 headerp->rm_xid = rqst->rq_xid; 398 headerp->rm_vers = rpcrdma_version; 399 headerp->rm_credit = cpu_to_be32(r_xprt->rx_buf.rb_max_requests); 400 headerp->rm_type = rdma_msg; 401 402 /* 403 * Chunks needed for results? 404 * 405 * o If the expected result is under the inline threshold, all ops 406 * return as inline (but see later). 407 * o Large non-read ops return as a single reply chunk. 408 * o Large read ops return data as write chunk(s), header as inline. 409 * 410 * Note: the NFS code sending down multiple result segments implies 411 * the op is one of read, readdir[plus], readlink or NFSv4 getacl. 412 */ 413 414 /* 415 * This code can handle read chunks, write chunks OR reply 416 * chunks -- only one type. If the request is too big to fit 417 * inline, then we will choose read chunks. If the request is 418 * a READ, then use write chunks to separate the file data 419 * into pages; otherwise use reply chunks. 420 */ 421 if (rqst->rq_rcv_buf.buflen <= RPCRDMA_INLINE_READ_THRESHOLD(rqst)) 422 wtype = rpcrdma_noch; 423 else if (rqst->rq_rcv_buf.page_len == 0) 424 wtype = rpcrdma_replych; 425 else if (rqst->rq_rcv_buf.flags & XDRBUF_READ) 426 wtype = rpcrdma_writech; 427 else 428 wtype = rpcrdma_replych; 429 430 /* 431 * Chunks needed for arguments? 432 * 433 * o If the total request is under the inline threshold, all ops 434 * are sent as inline. 435 * o Large non-write ops are sent with the entire message as a 436 * single read chunk (protocol 0-position special case). 437 * o Large write ops transmit data as read chunk(s), header as 438 * inline. 439 * 440 * Note: the NFS code sending down multiple argument segments 441 * implies the op is a write. 442 * TBD check NFSv4 setacl 443 */ 444 if (rqst->rq_snd_buf.len <= RPCRDMA_INLINE_WRITE_THRESHOLD(rqst)) 445 rtype = rpcrdma_noch; 446 else if (rqst->rq_snd_buf.page_len == 0) 447 rtype = rpcrdma_areadch; 448 else 449 rtype = rpcrdma_readch; 450 451 /* The following simplification is not true forever */ 452 if (rtype != rpcrdma_noch && wtype == rpcrdma_replych) 453 wtype = rpcrdma_noch; 454 if (rtype != rpcrdma_noch && wtype != rpcrdma_noch) { 455 dprintk("RPC: %s: cannot marshal multiple chunk lists\n", 456 __func__); 457 return -EIO; 458 } 459 460 hdrlen = RPCRDMA_HDRLEN_MIN; 461 padlen = 0; 462 463 /* 464 * Pull up any extra send data into the preregistered buffer. 465 * When padding is in use and applies to the transfer, insert 466 * it and change the message type. 467 */ 468 if (rtype == rpcrdma_noch) { 469 470 padlen = rpcrdma_inline_pullup(rqst, 471 RPCRDMA_INLINE_PAD_VALUE(rqst)); 472 473 if (padlen) { 474 headerp->rm_type = rdma_msgp; 475 headerp->rm_body.rm_padded.rm_align = 476 cpu_to_be32(RPCRDMA_INLINE_PAD_VALUE(rqst)); 477 headerp->rm_body.rm_padded.rm_thresh = 478 cpu_to_be32(RPCRDMA_INLINE_PAD_THRESH); 479 headerp->rm_body.rm_padded.rm_pempty[0] = xdr_zero; 480 headerp->rm_body.rm_padded.rm_pempty[1] = xdr_zero; 481 headerp->rm_body.rm_padded.rm_pempty[2] = xdr_zero; 482 hdrlen += 2 * sizeof(u32); /* extra words in padhdr */ 483 if (wtype != rpcrdma_noch) { 484 dprintk("RPC: %s: invalid chunk list\n", 485 __func__); 486 return -EIO; 487 } 488 } else { 489 headerp->rm_body.rm_nochunks.rm_empty[0] = xdr_zero; 490 headerp->rm_body.rm_nochunks.rm_empty[1] = xdr_zero; 491 headerp->rm_body.rm_nochunks.rm_empty[2] = xdr_zero; 492 /* new length after pullup */ 493 rpclen = rqst->rq_svec[0].iov_len; 494 /* 495 * Currently we try to not actually use read inline. 496 * Reply chunks have the desirable property that 497 * they land, packed, directly in the target buffers 498 * without headers, so they require no fixup. The 499 * additional RDMA Write op sends the same amount 500 * of data, streams on-the-wire and adds no overhead 501 * on receive. Therefore, we request a reply chunk 502 * for non-writes wherever feasible and efficient. 503 */ 504 if (wtype == rpcrdma_noch) 505 wtype = rpcrdma_replych; 506 } 507 } 508 509 if (rtype != rpcrdma_noch) { 510 hdrlen = rpcrdma_create_chunks(rqst, &rqst->rq_snd_buf, 511 headerp, rtype); 512 wtype = rtype; /* simplify dprintk */ 513 514 } else if (wtype != rpcrdma_noch) { 515 hdrlen = rpcrdma_create_chunks(rqst, &rqst->rq_rcv_buf, 516 headerp, wtype); 517 } 518 if (hdrlen < 0) 519 return hdrlen; 520 521 dprintk("RPC: %s: %s: hdrlen %zd rpclen %zd padlen %zd" 522 " headerp 0x%p base 0x%p lkey 0x%x\n", 523 __func__, transfertypes[wtype], hdrlen, rpclen, padlen, 524 headerp, base, rdmab_lkey(req->rl_rdmabuf)); 525 526 /* 527 * initialize send_iov's - normally only two: rdma chunk header and 528 * single preregistered RPC header buffer, but if padding is present, 529 * then use a preregistered (and zeroed) pad buffer between the RPC 530 * header and any write data. In all non-rdma cases, any following 531 * data has been copied into the RPC header buffer. 532 */ 533 req->rl_send_iov[0].addr = rdmab_addr(req->rl_rdmabuf); 534 req->rl_send_iov[0].length = hdrlen; 535 req->rl_send_iov[0].lkey = rdmab_lkey(req->rl_rdmabuf); 536 537 req->rl_send_iov[1].addr = rdmab_addr(req->rl_sendbuf); 538 req->rl_send_iov[1].length = rpclen; 539 req->rl_send_iov[1].lkey = rdmab_lkey(req->rl_sendbuf); 540 541 req->rl_niovs = 2; 542 543 if (padlen) { 544 struct rpcrdma_ep *ep = &r_xprt->rx_ep; 545 546 req->rl_send_iov[2].addr = rdmab_addr(ep->rep_padbuf); 547 req->rl_send_iov[2].length = padlen; 548 req->rl_send_iov[2].lkey = rdmab_lkey(ep->rep_padbuf); 549 550 req->rl_send_iov[3].addr = req->rl_send_iov[1].addr + rpclen; 551 req->rl_send_iov[3].length = rqst->rq_slen - rpclen; 552 req->rl_send_iov[3].lkey = rdmab_lkey(req->rl_sendbuf); 553 554 req->rl_niovs = 4; 555 } 556 557 return 0; 558 } 559 560 /* 561 * Chase down a received write or reply chunklist to get length 562 * RDMA'd by server. See map at rpcrdma_create_chunks()! :-) 563 */ 564 static int 565 rpcrdma_count_chunks(struct rpcrdma_rep *rep, unsigned int max, int wrchunk, __be32 **iptrp) 566 { 567 unsigned int i, total_len; 568 struct rpcrdma_write_chunk *cur_wchunk; 569 char *base = (char *)rdmab_to_msg(rep->rr_rdmabuf); 570 571 i = be32_to_cpu(**iptrp); 572 if (i > max) 573 return -1; 574 cur_wchunk = (struct rpcrdma_write_chunk *) (*iptrp + 1); 575 total_len = 0; 576 while (i--) { 577 struct rpcrdma_segment *seg = &cur_wchunk->wc_target; 578 ifdebug(FACILITY) { 579 u64 off; 580 xdr_decode_hyper((__be32 *)&seg->rs_offset, &off); 581 dprintk("RPC: %s: chunk %d@0x%llx:0x%x\n", 582 __func__, 583 be32_to_cpu(seg->rs_length), 584 (unsigned long long)off, 585 be32_to_cpu(seg->rs_handle)); 586 } 587 total_len += be32_to_cpu(seg->rs_length); 588 ++cur_wchunk; 589 } 590 /* check and adjust for properly terminated write chunk */ 591 if (wrchunk) { 592 __be32 *w = (__be32 *) cur_wchunk; 593 if (*w++ != xdr_zero) 594 return -1; 595 cur_wchunk = (struct rpcrdma_write_chunk *) w; 596 } 597 if ((char *)cur_wchunk > base + rep->rr_len) 598 return -1; 599 600 *iptrp = (__be32 *) cur_wchunk; 601 return total_len; 602 } 603 604 /* 605 * Scatter inline received data back into provided iov's. 606 */ 607 static void 608 rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad) 609 { 610 int i, npages, curlen, olen; 611 char *destp; 612 struct page **ppages; 613 int page_base; 614 615 curlen = rqst->rq_rcv_buf.head[0].iov_len; 616 if (curlen > copy_len) { /* write chunk header fixup */ 617 curlen = copy_len; 618 rqst->rq_rcv_buf.head[0].iov_len = curlen; 619 } 620 621 dprintk("RPC: %s: srcp 0x%p len %d hdrlen %d\n", 622 __func__, srcp, copy_len, curlen); 623 624 /* Shift pointer for first receive segment only */ 625 rqst->rq_rcv_buf.head[0].iov_base = srcp; 626 srcp += curlen; 627 copy_len -= curlen; 628 629 olen = copy_len; 630 i = 0; 631 rpcx_to_rdmax(rqst->rq_xprt)->rx_stats.fixup_copy_count += olen; 632 page_base = rqst->rq_rcv_buf.page_base; 633 ppages = rqst->rq_rcv_buf.pages + (page_base >> PAGE_SHIFT); 634 page_base &= ~PAGE_MASK; 635 636 if (copy_len && rqst->rq_rcv_buf.page_len) { 637 npages = PAGE_ALIGN(page_base + 638 rqst->rq_rcv_buf.page_len) >> PAGE_SHIFT; 639 for (; i < npages; i++) { 640 curlen = PAGE_SIZE - page_base; 641 if (curlen > copy_len) 642 curlen = copy_len; 643 dprintk("RPC: %s: page %d" 644 " srcp 0x%p len %d curlen %d\n", 645 __func__, i, srcp, copy_len, curlen); 646 destp = kmap_atomic(ppages[i]); 647 memcpy(destp + page_base, srcp, curlen); 648 flush_dcache_page(ppages[i]); 649 kunmap_atomic(destp); 650 srcp += curlen; 651 copy_len -= curlen; 652 if (copy_len == 0) 653 break; 654 page_base = 0; 655 } 656 } 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 void 688 rpcrdma_connect_worker(struct work_struct *work) 689 { 690 struct rpcrdma_ep *ep = 691 container_of(work, struct rpcrdma_ep, rep_connect_worker.work); 692 struct rpcrdma_xprt *r_xprt = 693 container_of(ep, struct rpcrdma_xprt, rx_ep); 694 struct rpc_xprt *xprt = &r_xprt->rx_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 rpcrdma_xprt *r_xprt = rep->rr_rxprt; 733 struct rpc_xprt *xprt = &r_xprt->rx_xprt; 734 __be32 *iptr; 735 int rdmalen, status; 736 unsigned long cwnd; 737 u32 credits; 738 739 /* Check status. If bad, signal disconnect and return rep to pool */ 740 if (rep->rr_len == ~0U) { 741 rpcrdma_recv_buffer_put(rep); 742 if (r_xprt->rx_ep.rep_connected == 1) { 743 r_xprt->rx_ep.rep_connected = -EIO; 744 rpcrdma_conn_func(&r_xprt->rx_ep); 745 } 746 return; 747 } 748 if (rep->rr_len < RPCRDMA_HDRLEN_MIN) { 749 dprintk("RPC: %s: short/invalid reply\n", __func__); 750 goto repost; 751 } 752 headerp = rdmab_to_msg(rep->rr_rdmabuf); 753 if (headerp->rm_vers != rpcrdma_version) { 754 dprintk("RPC: %s: invalid version %d\n", 755 __func__, be32_to_cpu(headerp->rm_vers)); 756 goto repost; 757 } 758 759 /* Get XID and try for a match. */ 760 spin_lock(&xprt->transport_lock); 761 rqst = xprt_lookup_rqst(xprt, headerp->rm_xid); 762 if (rqst == NULL) { 763 spin_unlock(&xprt->transport_lock); 764 dprintk("RPC: %s: reply 0x%p failed " 765 "to match any request xid 0x%08x len %d\n", 766 __func__, rep, be32_to_cpu(headerp->rm_xid), 767 rep->rr_len); 768 repost: 769 r_xprt->rx_stats.bad_reply_count++; 770 if (rpcrdma_ep_post_recv(&r_xprt->rx_ia, &r_xprt->rx_ep, rep)) 771 rpcrdma_recv_buffer_put(rep); 772 773 return; 774 } 775 776 /* get request object */ 777 req = rpcr_to_rdmar(rqst); 778 if (req->rl_reply) { 779 spin_unlock(&xprt->transport_lock); 780 dprintk("RPC: %s: duplicate reply 0x%p to RPC " 781 "request 0x%p: xid 0x%08x\n", __func__, rep, req, 782 be32_to_cpu(headerp->rm_xid)); 783 goto repost; 784 } 785 786 dprintk("RPC: %s: reply 0x%p completes request 0x%p\n" 787 " RPC request 0x%p xid 0x%08x\n", 788 __func__, rep, req, rqst, 789 be32_to_cpu(headerp->rm_xid)); 790 791 /* from here on, the reply is no longer an orphan */ 792 req->rl_reply = rep; 793 xprt->reestablish_timeout = 0; 794 795 /* check for expected message types */ 796 /* The order of some of these tests is important. */ 797 switch (headerp->rm_type) { 798 case rdma_msg: 799 /* never expect read chunks */ 800 /* never expect reply chunks (two ways to check) */ 801 /* never expect write chunks without having offered RDMA */ 802 if (headerp->rm_body.rm_chunks[0] != xdr_zero || 803 (headerp->rm_body.rm_chunks[1] == xdr_zero && 804 headerp->rm_body.rm_chunks[2] != xdr_zero) || 805 (headerp->rm_body.rm_chunks[1] != xdr_zero && 806 req->rl_nchunks == 0)) 807 goto badheader; 808 if (headerp->rm_body.rm_chunks[1] != xdr_zero) { 809 /* count any expected write chunks in read reply */ 810 /* start at write chunk array count */ 811 iptr = &headerp->rm_body.rm_chunks[2]; 812 rdmalen = rpcrdma_count_chunks(rep, 813 req->rl_nchunks, 1, &iptr); 814 /* check for validity, and no reply chunk after */ 815 if (rdmalen < 0 || *iptr++ != xdr_zero) 816 goto badheader; 817 rep->rr_len -= 818 ((unsigned char *)iptr - (unsigned char *)headerp); 819 status = rep->rr_len + rdmalen; 820 r_xprt->rx_stats.total_rdma_reply += rdmalen; 821 /* special case - last chunk may omit padding */ 822 if (rdmalen &= 3) { 823 rdmalen = 4 - rdmalen; 824 status += rdmalen; 825 } 826 } else { 827 /* else ordinary inline */ 828 rdmalen = 0; 829 iptr = (__be32 *)((unsigned char *)headerp + 830 RPCRDMA_HDRLEN_MIN); 831 rep->rr_len -= RPCRDMA_HDRLEN_MIN; 832 status = rep->rr_len; 833 } 834 /* Fix up the rpc results for upper layer */ 835 rpcrdma_inline_fixup(rqst, (char *)iptr, rep->rr_len, rdmalen); 836 break; 837 838 case rdma_nomsg: 839 /* never expect read or write chunks, always reply chunks */ 840 if (headerp->rm_body.rm_chunks[0] != xdr_zero || 841 headerp->rm_body.rm_chunks[1] != xdr_zero || 842 headerp->rm_body.rm_chunks[2] != xdr_one || 843 req->rl_nchunks == 0) 844 goto badheader; 845 iptr = (__be32 *)((unsigned char *)headerp + 846 RPCRDMA_HDRLEN_MIN); 847 rdmalen = rpcrdma_count_chunks(rep, req->rl_nchunks, 0, &iptr); 848 if (rdmalen < 0) 849 goto badheader; 850 r_xprt->rx_stats.total_rdma_reply += rdmalen; 851 /* Reply chunk buffer already is the reply vector - no fixup. */ 852 status = rdmalen; 853 break; 854 855 badheader: 856 default: 857 dprintk("%s: invalid rpcrdma reply header (type %d):" 858 " chunks[012] == %d %d %d" 859 " expected chunks <= %d\n", 860 __func__, be32_to_cpu(headerp->rm_type), 861 headerp->rm_body.rm_chunks[0], 862 headerp->rm_body.rm_chunks[1], 863 headerp->rm_body.rm_chunks[2], 864 req->rl_nchunks); 865 status = -EIO; 866 r_xprt->rx_stats.bad_reply_count++; 867 break; 868 } 869 870 credits = be32_to_cpu(headerp->rm_credit); 871 if (credits == 0) 872 credits = 1; /* don't deadlock */ 873 else if (credits > r_xprt->rx_buf.rb_max_requests) 874 credits = r_xprt->rx_buf.rb_max_requests; 875 876 cwnd = xprt->cwnd; 877 xprt->cwnd = credits << RPC_CWNDSHIFT; 878 if (xprt->cwnd > cwnd) 879 xprt_release_rqst_cong(rqst->rq_task); 880 881 dprintk("RPC: %s: xprt_complete_rqst(0x%p, 0x%p, %d)\n", 882 __func__, xprt, rqst, status); 883 xprt_complete_rqst(rqst->rq_task, status); 884 spin_unlock(&xprt->transport_lock); 885 } 886