1 /* 2 * Copyright (c) 2005-2006 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 * Author: Tom Tucker <tom@opengridcomputing.com> 40 */ 41 42 #include <linux/sunrpc/debug.h> 43 #include <linux/sunrpc/rpc_rdma.h> 44 #include <linux/spinlock.h> 45 #include <asm/unaligned.h> 46 #include <rdma/ib_verbs.h> 47 #include <rdma/rdma_cm.h> 48 #include <linux/sunrpc/svc_rdma.h> 49 50 #define RPCDBG_FACILITY RPCDBG_SVCXPRT 51 52 /* Encode an XDR as an array of IB SGE 53 * 54 * Assumptions: 55 * - head[0] is physically contiguous. 56 * - tail[0] is physically contiguous. 57 * - pages[] is not physically or virtually contigous and consists of 58 * PAGE_SIZE elements. 59 * 60 * Output: 61 * SGE[0] reserved for RCPRDMA header 62 * SGE[1] data from xdr->head[] 63 * SGE[2..sge_count-2] data from xdr->pages[] 64 * SGE[sge_count-1] data from xdr->tail. 65 * 66 * The max SGE we need is the length of the XDR / pagesize + one for 67 * head + one for tail + one for RPCRDMA header. Since RPCSVC_MAXPAGES 68 * reserves a page for both the request and the reply header, and this 69 * array is only concerned with the reply we are assured that we have 70 * on extra page for the RPCRMDA header. 71 */ 72 int fast_reg_xdr(struct svcxprt_rdma *xprt, 73 struct xdr_buf *xdr, 74 struct svc_rdma_req_map *vec) 75 { 76 int sge_no; 77 u32 sge_bytes; 78 u32 page_bytes; 79 u32 page_off; 80 int page_no = 0; 81 u8 *frva; 82 struct svc_rdma_fastreg_mr *frmr; 83 84 frmr = svc_rdma_get_frmr(xprt); 85 if (IS_ERR(frmr)) 86 return -ENOMEM; 87 vec->frmr = frmr; 88 89 /* Skip the RPCRDMA header */ 90 sge_no = 1; 91 92 /* Map the head. */ 93 frva = (void *)((unsigned long)(xdr->head[0].iov_base) & PAGE_MASK); 94 vec->sge[sge_no].iov_base = xdr->head[0].iov_base; 95 vec->sge[sge_no].iov_len = xdr->head[0].iov_len; 96 vec->count = 2; 97 sge_no++; 98 99 /* Build the FRMR */ 100 frmr->kva = frva; 101 frmr->direction = DMA_TO_DEVICE; 102 frmr->access_flags = 0; 103 frmr->map_len = PAGE_SIZE; 104 frmr->page_list_len = 1; 105 frmr->page_list->page_list[page_no] = 106 ib_dma_map_single(xprt->sc_cm_id->device, 107 (void *)xdr->head[0].iov_base, 108 PAGE_SIZE, DMA_TO_DEVICE); 109 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 110 frmr->page_list->page_list[page_no])) 111 goto fatal_err; 112 atomic_inc(&xprt->sc_dma_used); 113 114 page_off = xdr->page_base; 115 page_bytes = xdr->page_len + page_off; 116 if (!page_bytes) 117 goto encode_tail; 118 119 /* Map the pages */ 120 vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off; 121 vec->sge[sge_no].iov_len = page_bytes; 122 sge_no++; 123 while (page_bytes) { 124 struct page *page; 125 126 page = xdr->pages[page_no++]; 127 sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off)); 128 page_bytes -= sge_bytes; 129 130 frmr->page_list->page_list[page_no] = 131 ib_dma_map_page(xprt->sc_cm_id->device, page, 0, 132 PAGE_SIZE, DMA_TO_DEVICE); 133 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 134 frmr->page_list->page_list[page_no])) 135 goto fatal_err; 136 137 atomic_inc(&xprt->sc_dma_used); 138 page_off = 0; /* reset for next time through loop */ 139 frmr->map_len += PAGE_SIZE; 140 frmr->page_list_len++; 141 } 142 vec->count++; 143 144 encode_tail: 145 /* Map tail */ 146 if (0 == xdr->tail[0].iov_len) 147 goto done; 148 149 vec->count++; 150 vec->sge[sge_no].iov_len = xdr->tail[0].iov_len; 151 152 if (((unsigned long)xdr->tail[0].iov_base & PAGE_MASK) == 153 ((unsigned long)xdr->head[0].iov_base & PAGE_MASK)) { 154 /* 155 * If head and tail use the same page, we don't need 156 * to map it again. 157 */ 158 vec->sge[sge_no].iov_base = xdr->tail[0].iov_base; 159 } else { 160 void *va; 161 162 /* Map another page for the tail */ 163 page_off = (unsigned long)xdr->tail[0].iov_base & ~PAGE_MASK; 164 va = (void *)((unsigned long)xdr->tail[0].iov_base & PAGE_MASK); 165 vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off; 166 167 frmr->page_list->page_list[page_no] = 168 ib_dma_map_single(xprt->sc_cm_id->device, va, PAGE_SIZE, 169 DMA_TO_DEVICE); 170 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 171 frmr->page_list->page_list[page_no])) 172 goto fatal_err; 173 atomic_inc(&xprt->sc_dma_used); 174 frmr->map_len += PAGE_SIZE; 175 frmr->page_list_len++; 176 } 177 178 done: 179 if (svc_rdma_fastreg(xprt, frmr)) 180 goto fatal_err; 181 182 return 0; 183 184 fatal_err: 185 printk("svcrdma: Error fast registering memory for xprt %p\n", xprt); 186 svc_rdma_put_frmr(xprt, frmr); 187 return -EIO; 188 } 189 190 static int map_xdr(struct svcxprt_rdma *xprt, 191 struct xdr_buf *xdr, 192 struct svc_rdma_req_map *vec) 193 { 194 int sge_max = (xdr->len+PAGE_SIZE-1) / PAGE_SIZE + 3; 195 int sge_no; 196 u32 sge_bytes; 197 u32 page_bytes; 198 u32 page_off; 199 int page_no; 200 201 BUG_ON(xdr->len != 202 (xdr->head[0].iov_len + xdr->page_len + xdr->tail[0].iov_len)); 203 204 if (xprt->sc_frmr_pg_list_len) 205 return fast_reg_xdr(xprt, xdr, vec); 206 207 /* Skip the first sge, this is for the RPCRDMA header */ 208 sge_no = 1; 209 210 /* Head SGE */ 211 vec->sge[sge_no].iov_base = xdr->head[0].iov_base; 212 vec->sge[sge_no].iov_len = xdr->head[0].iov_len; 213 sge_no++; 214 215 /* pages SGE */ 216 page_no = 0; 217 page_bytes = xdr->page_len; 218 page_off = xdr->page_base; 219 while (page_bytes) { 220 vec->sge[sge_no].iov_base = 221 page_address(xdr->pages[page_no]) + page_off; 222 sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off)); 223 page_bytes -= sge_bytes; 224 vec->sge[sge_no].iov_len = sge_bytes; 225 226 sge_no++; 227 page_no++; 228 page_off = 0; /* reset for next time through loop */ 229 } 230 231 /* Tail SGE */ 232 if (xdr->tail[0].iov_len) { 233 vec->sge[sge_no].iov_base = xdr->tail[0].iov_base; 234 vec->sge[sge_no].iov_len = xdr->tail[0].iov_len; 235 sge_no++; 236 } 237 238 BUG_ON(sge_no > sge_max); 239 vec->count = sge_no; 240 return 0; 241 } 242 243 /* Assumptions: 244 * - We are using FRMR 245 * - or - 246 * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE 247 */ 248 static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp, 249 u32 rmr, u64 to, 250 u32 xdr_off, int write_len, 251 struct svc_rdma_req_map *vec) 252 { 253 struct ib_send_wr write_wr; 254 struct ib_sge *sge; 255 int xdr_sge_no; 256 int sge_no; 257 int sge_bytes; 258 int sge_off; 259 int bc; 260 struct svc_rdma_op_ctxt *ctxt; 261 262 BUG_ON(vec->count > RPCSVC_MAXPAGES); 263 dprintk("svcrdma: RDMA_WRITE rmr=%x, to=%llx, xdr_off=%d, " 264 "write_len=%d, vec->sge=%p, vec->count=%lu\n", 265 rmr, (unsigned long long)to, xdr_off, 266 write_len, vec->sge, vec->count); 267 268 ctxt = svc_rdma_get_context(xprt); 269 ctxt->direction = DMA_TO_DEVICE; 270 sge = ctxt->sge; 271 272 /* Find the SGE associated with xdr_off */ 273 for (bc = xdr_off, xdr_sge_no = 1; bc && xdr_sge_no < vec->count; 274 xdr_sge_no++) { 275 if (vec->sge[xdr_sge_no].iov_len > bc) 276 break; 277 bc -= vec->sge[xdr_sge_no].iov_len; 278 } 279 280 sge_off = bc; 281 bc = write_len; 282 sge_no = 0; 283 284 /* Copy the remaining SGE */ 285 while (bc != 0) { 286 sge_bytes = min_t(size_t, 287 bc, vec->sge[xdr_sge_no].iov_len-sge_off); 288 sge[sge_no].length = sge_bytes; 289 if (!vec->frmr) { 290 sge[sge_no].addr = 291 ib_dma_map_single(xprt->sc_cm_id->device, 292 (void *) 293 vec->sge[xdr_sge_no].iov_base + sge_off, 294 sge_bytes, DMA_TO_DEVICE); 295 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 296 sge[sge_no].addr)) 297 goto err; 298 atomic_inc(&xprt->sc_dma_used); 299 sge[sge_no].lkey = xprt->sc_dma_lkey; 300 } else { 301 sge[sge_no].addr = (unsigned long) 302 vec->sge[xdr_sge_no].iov_base + sge_off; 303 sge[sge_no].lkey = vec->frmr->mr->lkey; 304 } 305 ctxt->count++; 306 ctxt->frmr = vec->frmr; 307 sge_off = 0; 308 sge_no++; 309 xdr_sge_no++; 310 BUG_ON(xdr_sge_no > vec->count); 311 bc -= sge_bytes; 312 } 313 314 /* Prepare WRITE WR */ 315 memset(&write_wr, 0, sizeof write_wr); 316 ctxt->wr_op = IB_WR_RDMA_WRITE; 317 write_wr.wr_id = (unsigned long)ctxt; 318 write_wr.sg_list = &sge[0]; 319 write_wr.num_sge = sge_no; 320 write_wr.opcode = IB_WR_RDMA_WRITE; 321 write_wr.send_flags = IB_SEND_SIGNALED; 322 write_wr.wr.rdma.rkey = rmr; 323 write_wr.wr.rdma.remote_addr = to; 324 325 /* Post It */ 326 atomic_inc(&rdma_stat_write); 327 if (svc_rdma_send(xprt, &write_wr)) 328 goto err; 329 return 0; 330 err: 331 svc_rdma_put_context(ctxt, 0); 332 /* Fatal error, close transport */ 333 return -EIO; 334 } 335 336 static int send_write_chunks(struct svcxprt_rdma *xprt, 337 struct rpcrdma_msg *rdma_argp, 338 struct rpcrdma_msg *rdma_resp, 339 struct svc_rqst *rqstp, 340 struct svc_rdma_req_map *vec) 341 { 342 u32 xfer_len = rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len; 343 int write_len; 344 int max_write; 345 u32 xdr_off; 346 int chunk_off; 347 int chunk_no; 348 struct rpcrdma_write_array *arg_ary; 349 struct rpcrdma_write_array *res_ary; 350 int ret; 351 352 arg_ary = svc_rdma_get_write_array(rdma_argp); 353 if (!arg_ary) 354 return 0; 355 res_ary = (struct rpcrdma_write_array *) 356 &rdma_resp->rm_body.rm_chunks[1]; 357 358 if (vec->frmr) 359 max_write = vec->frmr->map_len; 360 else 361 max_write = xprt->sc_max_sge * PAGE_SIZE; 362 363 /* Write chunks start at the pagelist */ 364 for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0; 365 xfer_len && chunk_no < arg_ary->wc_nchunks; 366 chunk_no++) { 367 struct rpcrdma_segment *arg_ch; 368 u64 rs_offset; 369 370 arg_ch = &arg_ary->wc_array[chunk_no].wc_target; 371 write_len = min(xfer_len, arg_ch->rs_length); 372 373 /* Prepare the response chunk given the length actually 374 * written */ 375 rs_offset = get_unaligned(&(arg_ch->rs_offset)); 376 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, 377 arg_ch->rs_handle, 378 rs_offset, 379 write_len); 380 chunk_off = 0; 381 while (write_len) { 382 int this_write; 383 this_write = min(write_len, max_write); 384 ret = send_write(xprt, rqstp, 385 arg_ch->rs_handle, 386 rs_offset + chunk_off, 387 xdr_off, 388 this_write, 389 vec); 390 if (ret) { 391 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n", 392 ret); 393 return -EIO; 394 } 395 chunk_off += this_write; 396 xdr_off += this_write; 397 xfer_len -= this_write; 398 write_len -= this_write; 399 } 400 } 401 /* Update the req with the number of chunks actually used */ 402 svc_rdma_xdr_encode_write_list(rdma_resp, chunk_no); 403 404 return rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len; 405 } 406 407 static int send_reply_chunks(struct svcxprt_rdma *xprt, 408 struct rpcrdma_msg *rdma_argp, 409 struct rpcrdma_msg *rdma_resp, 410 struct svc_rqst *rqstp, 411 struct svc_rdma_req_map *vec) 412 { 413 u32 xfer_len = rqstp->rq_res.len; 414 int write_len; 415 int max_write; 416 u32 xdr_off; 417 int chunk_no; 418 int chunk_off; 419 struct rpcrdma_segment *ch; 420 struct rpcrdma_write_array *arg_ary; 421 struct rpcrdma_write_array *res_ary; 422 int ret; 423 424 arg_ary = svc_rdma_get_reply_array(rdma_argp); 425 if (!arg_ary) 426 return 0; 427 /* XXX: need to fix when reply lists occur with read-list and or 428 * write-list */ 429 res_ary = (struct rpcrdma_write_array *) 430 &rdma_resp->rm_body.rm_chunks[2]; 431 432 if (vec->frmr) 433 max_write = vec->frmr->map_len; 434 else 435 max_write = xprt->sc_max_sge * PAGE_SIZE; 436 437 /* xdr offset starts at RPC message */ 438 for (xdr_off = 0, chunk_no = 0; 439 xfer_len && chunk_no < arg_ary->wc_nchunks; 440 chunk_no++) { 441 u64 rs_offset; 442 ch = &arg_ary->wc_array[chunk_no].wc_target; 443 write_len = min(xfer_len, ch->rs_length); 444 445 /* Prepare the reply chunk given the length actually 446 * written */ 447 rs_offset = get_unaligned(&(ch->rs_offset)); 448 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, 449 ch->rs_handle, rs_offset, 450 write_len); 451 chunk_off = 0; 452 while (write_len) { 453 int this_write; 454 455 this_write = min(write_len, max_write); 456 ret = send_write(xprt, rqstp, 457 ch->rs_handle, 458 rs_offset + chunk_off, 459 xdr_off, 460 this_write, 461 vec); 462 if (ret) { 463 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n", 464 ret); 465 return -EIO; 466 } 467 chunk_off += this_write; 468 xdr_off += this_write; 469 xfer_len -= this_write; 470 write_len -= this_write; 471 } 472 } 473 /* Update the req with the number of chunks actually used */ 474 svc_rdma_xdr_encode_reply_array(res_ary, chunk_no); 475 476 return rqstp->rq_res.len; 477 } 478 479 /* This function prepares the portion of the RPCRDMA message to be 480 * sent in the RDMA_SEND. This function is called after data sent via 481 * RDMA has already been transmitted. There are three cases: 482 * - The RPCRDMA header, RPC header, and payload are all sent in a 483 * single RDMA_SEND. This is the "inline" case. 484 * - The RPCRDMA header and some portion of the RPC header and data 485 * are sent via this RDMA_SEND and another portion of the data is 486 * sent via RDMA. 487 * - The RPCRDMA header [NOMSG] is sent in this RDMA_SEND and the RPC 488 * header and data are all transmitted via RDMA. 489 * In all three cases, this function prepares the RPCRDMA header in 490 * sge[0], the 'type' parameter indicates the type to place in the 491 * RPCRDMA header, and the 'byte_count' field indicates how much of 492 * the XDR to include in this RDMA_SEND. 493 */ 494 static int send_reply(struct svcxprt_rdma *rdma, 495 struct svc_rqst *rqstp, 496 struct page *page, 497 struct rpcrdma_msg *rdma_resp, 498 struct svc_rdma_op_ctxt *ctxt, 499 struct svc_rdma_req_map *vec, 500 int byte_count) 501 { 502 struct ib_send_wr send_wr; 503 struct ib_send_wr inv_wr; 504 int sge_no; 505 int sge_bytes; 506 int page_no; 507 int ret; 508 509 /* Post a recv buffer to handle another request. */ 510 ret = svc_rdma_post_recv(rdma); 511 if (ret) { 512 printk(KERN_INFO 513 "svcrdma: could not post a receive buffer, err=%d." 514 "Closing transport %p.\n", ret, rdma); 515 set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags); 516 svc_rdma_put_context(ctxt, 0); 517 return -ENOTCONN; 518 } 519 520 /* Prepare the context */ 521 ctxt->pages[0] = page; 522 ctxt->count = 1; 523 ctxt->frmr = vec->frmr; 524 if (vec->frmr) 525 set_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags); 526 else 527 clear_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags); 528 529 /* Prepare the SGE for the RPCRDMA Header */ 530 ctxt->sge[0].addr = 531 ib_dma_map_page(rdma->sc_cm_id->device, 532 page, 0, PAGE_SIZE, DMA_TO_DEVICE); 533 if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr)) 534 goto err; 535 atomic_inc(&rdma->sc_dma_used); 536 537 ctxt->direction = DMA_TO_DEVICE; 538 539 ctxt->sge[0].length = svc_rdma_xdr_get_reply_hdr_len(rdma_resp); 540 ctxt->sge[0].lkey = rdma->sc_dma_lkey; 541 542 /* Determine how many of our SGE are to be transmitted */ 543 for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) { 544 sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count); 545 byte_count -= sge_bytes; 546 if (!vec->frmr) { 547 ctxt->sge[sge_no].addr = 548 ib_dma_map_single(rdma->sc_cm_id->device, 549 vec->sge[sge_no].iov_base, 550 sge_bytes, DMA_TO_DEVICE); 551 if (ib_dma_mapping_error(rdma->sc_cm_id->device, 552 ctxt->sge[sge_no].addr)) 553 goto err; 554 atomic_inc(&rdma->sc_dma_used); 555 ctxt->sge[sge_no].lkey = rdma->sc_dma_lkey; 556 } else { 557 ctxt->sge[sge_no].addr = (unsigned long) 558 vec->sge[sge_no].iov_base; 559 ctxt->sge[sge_no].lkey = vec->frmr->mr->lkey; 560 } 561 ctxt->sge[sge_no].length = sge_bytes; 562 } 563 BUG_ON(byte_count != 0); 564 565 /* Save all respages in the ctxt and remove them from the 566 * respages array. They are our pages until the I/O 567 * completes. 568 */ 569 for (page_no = 0; page_no < rqstp->rq_resused; page_no++) { 570 ctxt->pages[page_no+1] = rqstp->rq_respages[page_no]; 571 ctxt->count++; 572 rqstp->rq_respages[page_no] = NULL; 573 /* 574 * If there are more pages than SGE, terminate SGE 575 * list so that svc_rdma_unmap_dma doesn't attempt to 576 * unmap garbage. 577 */ 578 if (page_no+1 >= sge_no) 579 ctxt->sge[page_no+1].length = 0; 580 } 581 BUG_ON(sge_no > rdma->sc_max_sge); 582 BUG_ON(sge_no > ctxt->count); 583 memset(&send_wr, 0, sizeof send_wr); 584 ctxt->wr_op = IB_WR_SEND; 585 send_wr.wr_id = (unsigned long)ctxt; 586 send_wr.sg_list = ctxt->sge; 587 send_wr.num_sge = sge_no; 588 send_wr.opcode = IB_WR_SEND; 589 send_wr.send_flags = IB_SEND_SIGNALED; 590 if (vec->frmr) { 591 /* Prepare INVALIDATE WR */ 592 memset(&inv_wr, 0, sizeof inv_wr); 593 inv_wr.opcode = IB_WR_LOCAL_INV; 594 inv_wr.send_flags = IB_SEND_SIGNALED; 595 inv_wr.ex.invalidate_rkey = 596 vec->frmr->mr->lkey; 597 send_wr.next = &inv_wr; 598 } 599 600 ret = svc_rdma_send(rdma, &send_wr); 601 if (ret) 602 goto err; 603 604 return 0; 605 606 err: 607 svc_rdma_put_frmr(rdma, vec->frmr); 608 svc_rdma_put_context(ctxt, 1); 609 return -EIO; 610 } 611 612 void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp) 613 { 614 } 615 616 /* 617 * Return the start of an xdr buffer. 618 */ 619 static void *xdr_start(struct xdr_buf *xdr) 620 { 621 return xdr->head[0].iov_base - 622 (xdr->len - 623 xdr->page_len - 624 xdr->tail[0].iov_len - 625 xdr->head[0].iov_len); 626 } 627 628 int svc_rdma_sendto(struct svc_rqst *rqstp) 629 { 630 struct svc_xprt *xprt = rqstp->rq_xprt; 631 struct svcxprt_rdma *rdma = 632 container_of(xprt, struct svcxprt_rdma, sc_xprt); 633 struct rpcrdma_msg *rdma_argp; 634 struct rpcrdma_msg *rdma_resp; 635 struct rpcrdma_write_array *reply_ary; 636 enum rpcrdma_proc reply_type; 637 int ret; 638 int inline_bytes; 639 struct page *res_page; 640 struct svc_rdma_op_ctxt *ctxt; 641 struct svc_rdma_req_map *vec; 642 643 dprintk("svcrdma: sending response for rqstp=%p\n", rqstp); 644 645 /* Get the RDMA request header. */ 646 rdma_argp = xdr_start(&rqstp->rq_arg); 647 648 /* Build an req vec for the XDR */ 649 ctxt = svc_rdma_get_context(rdma); 650 ctxt->direction = DMA_TO_DEVICE; 651 vec = svc_rdma_get_req_map(); 652 ret = map_xdr(rdma, &rqstp->rq_res, vec); 653 if (ret) 654 goto err0; 655 inline_bytes = rqstp->rq_res.len; 656 657 /* Create the RDMA response header */ 658 res_page = svc_rdma_get_page(); 659 rdma_resp = page_address(res_page); 660 reply_ary = svc_rdma_get_reply_array(rdma_argp); 661 if (reply_ary) 662 reply_type = RDMA_NOMSG; 663 else 664 reply_type = RDMA_MSG; 665 svc_rdma_xdr_encode_reply_header(rdma, rdma_argp, 666 rdma_resp, reply_type); 667 668 /* Send any write-chunk data and build resp write-list */ 669 ret = send_write_chunks(rdma, rdma_argp, rdma_resp, 670 rqstp, vec); 671 if (ret < 0) { 672 printk(KERN_ERR "svcrdma: failed to send write chunks, rc=%d\n", 673 ret); 674 goto err1; 675 } 676 inline_bytes -= ret; 677 678 /* Send any reply-list data and update resp reply-list */ 679 ret = send_reply_chunks(rdma, rdma_argp, rdma_resp, 680 rqstp, vec); 681 if (ret < 0) { 682 printk(KERN_ERR "svcrdma: failed to send reply chunks, rc=%d\n", 683 ret); 684 goto err1; 685 } 686 inline_bytes -= ret; 687 688 ret = send_reply(rdma, rqstp, res_page, rdma_resp, ctxt, vec, 689 inline_bytes); 690 svc_rdma_put_req_map(vec); 691 dprintk("svcrdma: send_reply returns %d\n", ret); 692 return ret; 693 694 err1: 695 put_page(res_page); 696 err0: 697 svc_rdma_put_req_map(vec); 698 svc_rdma_put_context(ctxt, 0); 699 return ret; 700 } 701