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 static 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_no; 195 u32 sge_bytes; 196 u32 page_bytes; 197 u32 page_off; 198 int page_no; 199 200 BUG_ON(xdr->len != 201 (xdr->head[0].iov_len + xdr->page_len + xdr->tail[0].iov_len)); 202 203 if (xprt->sc_frmr_pg_list_len) 204 return fast_reg_xdr(xprt, xdr, vec); 205 206 /* Skip the first sge, this is for the RPCRDMA header */ 207 sge_no = 1; 208 209 /* Head SGE */ 210 vec->sge[sge_no].iov_base = xdr->head[0].iov_base; 211 vec->sge[sge_no].iov_len = xdr->head[0].iov_len; 212 sge_no++; 213 214 /* pages SGE */ 215 page_no = 0; 216 page_bytes = xdr->page_len; 217 page_off = xdr->page_base; 218 while (page_bytes) { 219 vec->sge[sge_no].iov_base = 220 page_address(xdr->pages[page_no]) + page_off; 221 sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off)); 222 page_bytes -= sge_bytes; 223 vec->sge[sge_no].iov_len = sge_bytes; 224 225 sge_no++; 226 page_no++; 227 page_off = 0; /* reset for next time through loop */ 228 } 229 230 /* Tail SGE */ 231 if (xdr->tail[0].iov_len) { 232 vec->sge[sge_no].iov_base = xdr->tail[0].iov_base; 233 vec->sge[sge_no].iov_len = xdr->tail[0].iov_len; 234 sge_no++; 235 } 236 237 dprintk("svcrdma: map_xdr: sge_no %d page_no %d " 238 "page_base %u page_len %u head_len %zu tail_len %zu\n", 239 sge_no, page_no, xdr->page_base, xdr->page_len, 240 xdr->head[0].iov_len, xdr->tail[0].iov_len); 241 242 vec->count = sge_no; 243 return 0; 244 } 245 246 /* Assumptions: 247 * - We are using FRMR 248 * - or - 249 * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE 250 */ 251 static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp, 252 u32 rmr, u64 to, 253 u32 xdr_off, int write_len, 254 struct svc_rdma_req_map *vec) 255 { 256 struct ib_send_wr write_wr; 257 struct ib_sge *sge; 258 int xdr_sge_no; 259 int sge_no; 260 int sge_bytes; 261 int sge_off; 262 int bc; 263 struct svc_rdma_op_ctxt *ctxt; 264 265 BUG_ON(vec->count > RPCSVC_MAXPAGES); 266 dprintk("svcrdma: RDMA_WRITE rmr=%x, to=%llx, xdr_off=%d, " 267 "write_len=%d, vec->sge=%p, vec->count=%lu\n", 268 rmr, (unsigned long long)to, xdr_off, 269 write_len, vec->sge, vec->count); 270 271 ctxt = svc_rdma_get_context(xprt); 272 ctxt->direction = DMA_TO_DEVICE; 273 sge = ctxt->sge; 274 275 /* Find the SGE associated with xdr_off */ 276 for (bc = xdr_off, xdr_sge_no = 1; bc && xdr_sge_no < vec->count; 277 xdr_sge_no++) { 278 if (vec->sge[xdr_sge_no].iov_len > bc) 279 break; 280 bc -= vec->sge[xdr_sge_no].iov_len; 281 } 282 283 sge_off = bc; 284 bc = write_len; 285 sge_no = 0; 286 287 /* Copy the remaining SGE */ 288 while (bc != 0) { 289 sge_bytes = min_t(size_t, 290 bc, vec->sge[xdr_sge_no].iov_len-sge_off); 291 sge[sge_no].length = sge_bytes; 292 if (!vec->frmr) { 293 sge[sge_no].addr = 294 ib_dma_map_single(xprt->sc_cm_id->device, 295 (void *) 296 vec->sge[xdr_sge_no].iov_base + sge_off, 297 sge_bytes, DMA_TO_DEVICE); 298 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 299 sge[sge_no].addr)) 300 goto err; 301 atomic_inc(&xprt->sc_dma_used); 302 sge[sge_no].lkey = xprt->sc_dma_lkey; 303 } else { 304 sge[sge_no].addr = (unsigned long) 305 vec->sge[xdr_sge_no].iov_base + sge_off; 306 sge[sge_no].lkey = vec->frmr->mr->lkey; 307 } 308 ctxt->count++; 309 ctxt->frmr = vec->frmr; 310 sge_off = 0; 311 sge_no++; 312 xdr_sge_no++; 313 BUG_ON(xdr_sge_no > vec->count); 314 bc -= sge_bytes; 315 } 316 317 /* Prepare WRITE WR */ 318 memset(&write_wr, 0, sizeof write_wr); 319 ctxt->wr_op = IB_WR_RDMA_WRITE; 320 write_wr.wr_id = (unsigned long)ctxt; 321 write_wr.sg_list = &sge[0]; 322 write_wr.num_sge = sge_no; 323 write_wr.opcode = IB_WR_RDMA_WRITE; 324 write_wr.send_flags = IB_SEND_SIGNALED; 325 write_wr.wr.rdma.rkey = rmr; 326 write_wr.wr.rdma.remote_addr = to; 327 328 /* Post It */ 329 atomic_inc(&rdma_stat_write); 330 if (svc_rdma_send(xprt, &write_wr)) 331 goto err; 332 return 0; 333 err: 334 svc_rdma_put_context(ctxt, 0); 335 /* Fatal error, close transport */ 336 return -EIO; 337 } 338 339 static int send_write_chunks(struct svcxprt_rdma *xprt, 340 struct rpcrdma_msg *rdma_argp, 341 struct rpcrdma_msg *rdma_resp, 342 struct svc_rqst *rqstp, 343 struct svc_rdma_req_map *vec) 344 { 345 u32 xfer_len = rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len; 346 int write_len; 347 int max_write; 348 u32 xdr_off; 349 int chunk_off; 350 int chunk_no; 351 struct rpcrdma_write_array *arg_ary; 352 struct rpcrdma_write_array *res_ary; 353 int ret; 354 355 arg_ary = svc_rdma_get_write_array(rdma_argp); 356 if (!arg_ary) 357 return 0; 358 res_ary = (struct rpcrdma_write_array *) 359 &rdma_resp->rm_body.rm_chunks[1]; 360 361 if (vec->frmr) 362 max_write = vec->frmr->map_len; 363 else 364 max_write = xprt->sc_max_sge * PAGE_SIZE; 365 366 /* Write chunks start at the pagelist */ 367 for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0; 368 xfer_len && chunk_no < arg_ary->wc_nchunks; 369 chunk_no++) { 370 struct rpcrdma_segment *arg_ch; 371 u64 rs_offset; 372 373 arg_ch = &arg_ary->wc_array[chunk_no].wc_target; 374 write_len = min(xfer_len, arg_ch->rs_length); 375 376 /* Prepare the response chunk given the length actually 377 * written */ 378 rs_offset = get_unaligned(&(arg_ch->rs_offset)); 379 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, 380 arg_ch->rs_handle, 381 rs_offset, 382 write_len); 383 chunk_off = 0; 384 while (write_len) { 385 int this_write; 386 this_write = min(write_len, max_write); 387 ret = send_write(xprt, rqstp, 388 arg_ch->rs_handle, 389 rs_offset + chunk_off, 390 xdr_off, 391 this_write, 392 vec); 393 if (ret) { 394 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n", 395 ret); 396 return -EIO; 397 } 398 chunk_off += this_write; 399 xdr_off += this_write; 400 xfer_len -= this_write; 401 write_len -= this_write; 402 } 403 } 404 /* Update the req with the number of chunks actually used */ 405 svc_rdma_xdr_encode_write_list(rdma_resp, chunk_no); 406 407 return rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len; 408 } 409 410 static int send_reply_chunks(struct svcxprt_rdma *xprt, 411 struct rpcrdma_msg *rdma_argp, 412 struct rpcrdma_msg *rdma_resp, 413 struct svc_rqst *rqstp, 414 struct svc_rdma_req_map *vec) 415 { 416 u32 xfer_len = rqstp->rq_res.len; 417 int write_len; 418 int max_write; 419 u32 xdr_off; 420 int chunk_no; 421 int chunk_off; 422 struct rpcrdma_segment *ch; 423 struct rpcrdma_write_array *arg_ary; 424 struct rpcrdma_write_array *res_ary; 425 int ret; 426 427 arg_ary = svc_rdma_get_reply_array(rdma_argp); 428 if (!arg_ary) 429 return 0; 430 /* XXX: need to fix when reply lists occur with read-list and or 431 * write-list */ 432 res_ary = (struct rpcrdma_write_array *) 433 &rdma_resp->rm_body.rm_chunks[2]; 434 435 if (vec->frmr) 436 max_write = vec->frmr->map_len; 437 else 438 max_write = xprt->sc_max_sge * PAGE_SIZE; 439 440 /* xdr offset starts at RPC message */ 441 for (xdr_off = 0, chunk_no = 0; 442 xfer_len && chunk_no < arg_ary->wc_nchunks; 443 chunk_no++) { 444 u64 rs_offset; 445 ch = &arg_ary->wc_array[chunk_no].wc_target; 446 write_len = min(xfer_len, ch->rs_length); 447 448 /* Prepare the reply chunk given the length actually 449 * written */ 450 rs_offset = get_unaligned(&(ch->rs_offset)); 451 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, 452 ch->rs_handle, rs_offset, 453 write_len); 454 chunk_off = 0; 455 while (write_len) { 456 int this_write; 457 458 this_write = min(write_len, max_write); 459 ret = send_write(xprt, rqstp, 460 ch->rs_handle, 461 rs_offset + chunk_off, 462 xdr_off, 463 this_write, 464 vec); 465 if (ret) { 466 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n", 467 ret); 468 return -EIO; 469 } 470 chunk_off += this_write; 471 xdr_off += this_write; 472 xfer_len -= this_write; 473 write_len -= this_write; 474 } 475 } 476 /* Update the req with the number of chunks actually used */ 477 svc_rdma_xdr_encode_reply_array(res_ary, chunk_no); 478 479 return rqstp->rq_res.len; 480 } 481 482 /* This function prepares the portion of the RPCRDMA message to be 483 * sent in the RDMA_SEND. This function is called after data sent via 484 * RDMA has already been transmitted. There are three cases: 485 * - The RPCRDMA header, RPC header, and payload are all sent in a 486 * single RDMA_SEND. This is the "inline" case. 487 * - The RPCRDMA header and some portion of the RPC header and data 488 * are sent via this RDMA_SEND and another portion of the data is 489 * sent via RDMA. 490 * - The RPCRDMA header [NOMSG] is sent in this RDMA_SEND and the RPC 491 * header and data are all transmitted via RDMA. 492 * In all three cases, this function prepares the RPCRDMA header in 493 * sge[0], the 'type' parameter indicates the type to place in the 494 * RPCRDMA header, and the 'byte_count' field indicates how much of 495 * the XDR to include in this RDMA_SEND. 496 */ 497 static int send_reply(struct svcxprt_rdma *rdma, 498 struct svc_rqst *rqstp, 499 struct page *page, 500 struct rpcrdma_msg *rdma_resp, 501 struct svc_rdma_op_ctxt *ctxt, 502 struct svc_rdma_req_map *vec, 503 int byte_count) 504 { 505 struct ib_send_wr send_wr; 506 struct ib_send_wr inv_wr; 507 int sge_no; 508 int sge_bytes; 509 int page_no; 510 int ret; 511 512 /* Post a recv buffer to handle another request. */ 513 ret = svc_rdma_post_recv(rdma); 514 if (ret) { 515 printk(KERN_INFO 516 "svcrdma: could not post a receive buffer, err=%d." 517 "Closing transport %p.\n", ret, rdma); 518 set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags); 519 svc_rdma_put_context(ctxt, 0); 520 return -ENOTCONN; 521 } 522 523 /* Prepare the context */ 524 ctxt->pages[0] = page; 525 ctxt->count = 1; 526 ctxt->frmr = vec->frmr; 527 if (vec->frmr) 528 set_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags); 529 else 530 clear_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags); 531 532 /* Prepare the SGE for the RPCRDMA Header */ 533 ctxt->sge[0].addr = 534 ib_dma_map_page(rdma->sc_cm_id->device, 535 page, 0, PAGE_SIZE, DMA_TO_DEVICE); 536 if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr)) 537 goto err; 538 atomic_inc(&rdma->sc_dma_used); 539 540 ctxt->direction = DMA_TO_DEVICE; 541 542 ctxt->sge[0].length = svc_rdma_xdr_get_reply_hdr_len(rdma_resp); 543 ctxt->sge[0].lkey = rdma->sc_dma_lkey; 544 545 /* Determine how many of our SGE are to be transmitted */ 546 for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) { 547 sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count); 548 byte_count -= sge_bytes; 549 if (!vec->frmr) { 550 ctxt->sge[sge_no].addr = 551 ib_dma_map_single(rdma->sc_cm_id->device, 552 vec->sge[sge_no].iov_base, 553 sge_bytes, DMA_TO_DEVICE); 554 if (ib_dma_mapping_error(rdma->sc_cm_id->device, 555 ctxt->sge[sge_no].addr)) 556 goto err; 557 atomic_inc(&rdma->sc_dma_used); 558 ctxt->sge[sge_no].lkey = rdma->sc_dma_lkey; 559 } else { 560 ctxt->sge[sge_no].addr = (unsigned long) 561 vec->sge[sge_no].iov_base; 562 ctxt->sge[sge_no].lkey = vec->frmr->mr->lkey; 563 } 564 ctxt->sge[sge_no].length = sge_bytes; 565 } 566 BUG_ON(byte_count != 0); 567 568 /* Save all respages in the ctxt and remove them from the 569 * respages array. They are our pages until the I/O 570 * completes. 571 */ 572 for (page_no = 0; page_no < rqstp->rq_resused; page_no++) { 573 ctxt->pages[page_no+1] = rqstp->rq_respages[page_no]; 574 ctxt->count++; 575 rqstp->rq_respages[page_no] = NULL; 576 /* 577 * If there are more pages than SGE, terminate SGE 578 * list so that svc_rdma_unmap_dma doesn't attempt to 579 * unmap garbage. 580 */ 581 if (page_no+1 >= sge_no) 582 ctxt->sge[page_no+1].length = 0; 583 } 584 BUG_ON(sge_no > rdma->sc_max_sge); 585 memset(&send_wr, 0, sizeof send_wr); 586 ctxt->wr_op = IB_WR_SEND; 587 send_wr.wr_id = (unsigned long)ctxt; 588 send_wr.sg_list = ctxt->sge; 589 send_wr.num_sge = sge_no; 590 send_wr.opcode = IB_WR_SEND; 591 send_wr.send_flags = IB_SEND_SIGNALED; 592 if (vec->frmr) { 593 /* Prepare INVALIDATE WR */ 594 memset(&inv_wr, 0, sizeof inv_wr); 595 inv_wr.opcode = IB_WR_LOCAL_INV; 596 inv_wr.send_flags = IB_SEND_SIGNALED; 597 inv_wr.ex.invalidate_rkey = 598 vec->frmr->mr->lkey; 599 send_wr.next = &inv_wr; 600 } 601 602 ret = svc_rdma_send(rdma, &send_wr); 603 if (ret) 604 goto err; 605 606 return 0; 607 608 err: 609 svc_rdma_put_frmr(rdma, vec->frmr); 610 svc_rdma_put_context(ctxt, 1); 611 return -EIO; 612 } 613 614 void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp) 615 { 616 } 617 618 /* 619 * Return the start of an xdr buffer. 620 */ 621 static void *xdr_start(struct xdr_buf *xdr) 622 { 623 return xdr->head[0].iov_base - 624 (xdr->len - 625 xdr->page_len - 626 xdr->tail[0].iov_len - 627 xdr->head[0].iov_len); 628 } 629 630 int svc_rdma_sendto(struct svc_rqst *rqstp) 631 { 632 struct svc_xprt *xprt = rqstp->rq_xprt; 633 struct svcxprt_rdma *rdma = 634 container_of(xprt, struct svcxprt_rdma, sc_xprt); 635 struct rpcrdma_msg *rdma_argp; 636 struct rpcrdma_msg *rdma_resp; 637 struct rpcrdma_write_array *reply_ary; 638 enum rpcrdma_proc reply_type; 639 int ret; 640 int inline_bytes; 641 struct page *res_page; 642 struct svc_rdma_op_ctxt *ctxt; 643 struct svc_rdma_req_map *vec; 644 645 dprintk("svcrdma: sending response for rqstp=%p\n", rqstp); 646 647 /* Get the RDMA request header. */ 648 rdma_argp = xdr_start(&rqstp->rq_arg); 649 650 /* Build an req vec for the XDR */ 651 ctxt = svc_rdma_get_context(rdma); 652 ctxt->direction = DMA_TO_DEVICE; 653 vec = svc_rdma_get_req_map(); 654 ret = map_xdr(rdma, &rqstp->rq_res, vec); 655 if (ret) 656 goto err0; 657 inline_bytes = rqstp->rq_res.len; 658 659 /* Create the RDMA response header */ 660 res_page = svc_rdma_get_page(); 661 rdma_resp = page_address(res_page); 662 reply_ary = svc_rdma_get_reply_array(rdma_argp); 663 if (reply_ary) 664 reply_type = RDMA_NOMSG; 665 else 666 reply_type = RDMA_MSG; 667 svc_rdma_xdr_encode_reply_header(rdma, rdma_argp, 668 rdma_resp, reply_type); 669 670 /* Send any write-chunk data and build resp write-list */ 671 ret = send_write_chunks(rdma, rdma_argp, rdma_resp, 672 rqstp, vec); 673 if (ret < 0) { 674 printk(KERN_ERR "svcrdma: failed to send write chunks, rc=%d\n", 675 ret); 676 goto err1; 677 } 678 inline_bytes -= ret; 679 680 /* Send any reply-list data and update resp reply-list */ 681 ret = send_reply_chunks(rdma, rdma_argp, rdma_resp, 682 rqstp, vec); 683 if (ret < 0) { 684 printk(KERN_ERR "svcrdma: failed to send reply chunks, rc=%d\n", 685 ret); 686 goto err1; 687 } 688 inline_bytes -= ret; 689 690 ret = send_reply(rdma, rqstp, res_page, rdma_resp, ctxt, vec, 691 inline_bytes); 692 svc_rdma_put_req_map(vec); 693 dprintk("svcrdma: send_reply returns %d\n", ret); 694 return ret; 695 696 err1: 697 put_page(res_page); 698 err0: 699 svc_rdma_put_req_map(vec); 700 svc_rdma_put_context(ctxt, 0); 701 return ret; 702 } 703