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 contiguous 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 /* Map the XDR head */ 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 page_off = (unsigned long)xdr->head[0].iov_base & ~PAGE_MASK; 106 frmr->page_list->page_list[page_no] = 107 ib_dma_map_page(xprt->sc_cm_id->device, 108 virt_to_page(xdr->head[0].iov_base), 109 page_off, 110 PAGE_SIZE - page_off, 111 DMA_TO_DEVICE); 112 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 113 frmr->page_list->page_list[page_no])) 114 goto fatal_err; 115 atomic_inc(&xprt->sc_dma_used); 116 117 /* Map the XDR page list */ 118 page_off = xdr->page_base; 119 page_bytes = xdr->page_len + page_off; 120 if (!page_bytes) 121 goto encode_tail; 122 123 /* Map the pages */ 124 vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off; 125 vec->sge[sge_no].iov_len = page_bytes; 126 sge_no++; 127 while (page_bytes) { 128 struct page *page; 129 130 page = xdr->pages[page_no++]; 131 sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off)); 132 page_bytes -= sge_bytes; 133 134 frmr->page_list->page_list[page_no] = 135 ib_dma_map_page(xprt->sc_cm_id->device, 136 page, page_off, 137 sge_bytes, DMA_TO_DEVICE); 138 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 139 frmr->page_list->page_list[page_no])) 140 goto fatal_err; 141 142 atomic_inc(&xprt->sc_dma_used); 143 page_off = 0; /* reset for next time through loop */ 144 frmr->map_len += PAGE_SIZE; 145 frmr->page_list_len++; 146 } 147 vec->count++; 148 149 encode_tail: 150 /* Map tail */ 151 if (0 == xdr->tail[0].iov_len) 152 goto done; 153 154 vec->count++; 155 vec->sge[sge_no].iov_len = xdr->tail[0].iov_len; 156 157 if (((unsigned long)xdr->tail[0].iov_base & PAGE_MASK) == 158 ((unsigned long)xdr->head[0].iov_base & PAGE_MASK)) { 159 /* 160 * If head and tail use the same page, we don't need 161 * to map it again. 162 */ 163 vec->sge[sge_no].iov_base = xdr->tail[0].iov_base; 164 } else { 165 void *va; 166 167 /* Map another page for the tail */ 168 page_off = (unsigned long)xdr->tail[0].iov_base & ~PAGE_MASK; 169 va = (void *)((unsigned long)xdr->tail[0].iov_base & PAGE_MASK); 170 vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off; 171 172 frmr->page_list->page_list[page_no] = 173 ib_dma_map_page(xprt->sc_cm_id->device, virt_to_page(va), 174 page_off, 175 PAGE_SIZE, 176 DMA_TO_DEVICE); 177 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 178 frmr->page_list->page_list[page_no])) 179 goto fatal_err; 180 atomic_inc(&xprt->sc_dma_used); 181 frmr->map_len += PAGE_SIZE; 182 frmr->page_list_len++; 183 } 184 185 done: 186 if (svc_rdma_fastreg(xprt, frmr)) 187 goto fatal_err; 188 189 return 0; 190 191 fatal_err: 192 printk("svcrdma: Error fast registering memory for xprt %p\n", xprt); 193 vec->frmr = NULL; 194 svc_rdma_put_frmr(xprt, frmr); 195 return -EIO; 196 } 197 198 static int map_xdr(struct svcxprt_rdma *xprt, 199 struct xdr_buf *xdr, 200 struct svc_rdma_req_map *vec) 201 { 202 int sge_no; 203 u32 sge_bytes; 204 u32 page_bytes; 205 u32 page_off; 206 int page_no; 207 208 BUG_ON(xdr->len != 209 (xdr->head[0].iov_len + xdr->page_len + xdr->tail[0].iov_len)); 210 211 if (xprt->sc_frmr_pg_list_len) 212 return fast_reg_xdr(xprt, xdr, vec); 213 214 /* Skip the first sge, this is for the RPCRDMA header */ 215 sge_no = 1; 216 217 /* Head SGE */ 218 vec->sge[sge_no].iov_base = xdr->head[0].iov_base; 219 vec->sge[sge_no].iov_len = xdr->head[0].iov_len; 220 sge_no++; 221 222 /* pages SGE */ 223 page_no = 0; 224 page_bytes = xdr->page_len; 225 page_off = xdr->page_base; 226 while (page_bytes) { 227 vec->sge[sge_no].iov_base = 228 page_address(xdr->pages[page_no]) + page_off; 229 sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off)); 230 page_bytes -= sge_bytes; 231 vec->sge[sge_no].iov_len = sge_bytes; 232 233 sge_no++; 234 page_no++; 235 page_off = 0; /* reset for next time through loop */ 236 } 237 238 /* Tail SGE */ 239 if (xdr->tail[0].iov_len) { 240 vec->sge[sge_no].iov_base = xdr->tail[0].iov_base; 241 vec->sge[sge_no].iov_len = xdr->tail[0].iov_len; 242 sge_no++; 243 } 244 245 dprintk("svcrdma: map_xdr: sge_no %d page_no %d " 246 "page_base %u page_len %u head_len %zu tail_len %zu\n", 247 sge_no, page_no, xdr->page_base, xdr->page_len, 248 xdr->head[0].iov_len, xdr->tail[0].iov_len); 249 250 vec->count = sge_no; 251 return 0; 252 } 253 254 static dma_addr_t dma_map_xdr(struct svcxprt_rdma *xprt, 255 struct xdr_buf *xdr, 256 u32 xdr_off, size_t len, int dir) 257 { 258 struct page *page; 259 dma_addr_t dma_addr; 260 if (xdr_off < xdr->head[0].iov_len) { 261 /* This offset is in the head */ 262 xdr_off += (unsigned long)xdr->head[0].iov_base & ~PAGE_MASK; 263 page = virt_to_page(xdr->head[0].iov_base); 264 } else { 265 xdr_off -= xdr->head[0].iov_len; 266 if (xdr_off < xdr->page_len) { 267 /* This offset is in the page list */ 268 page = xdr->pages[xdr_off >> PAGE_SHIFT]; 269 xdr_off &= ~PAGE_MASK; 270 } else { 271 /* This offset is in the tail */ 272 xdr_off -= xdr->page_len; 273 xdr_off += (unsigned long) 274 xdr->tail[0].iov_base & ~PAGE_MASK; 275 page = virt_to_page(xdr->tail[0].iov_base); 276 } 277 } 278 dma_addr = ib_dma_map_page(xprt->sc_cm_id->device, page, xdr_off, 279 min_t(size_t, PAGE_SIZE, len), dir); 280 return dma_addr; 281 } 282 283 /* Assumptions: 284 * - We are using FRMR 285 * - or - 286 * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE 287 */ 288 static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp, 289 u32 rmr, u64 to, 290 u32 xdr_off, int write_len, 291 struct svc_rdma_req_map *vec) 292 { 293 struct ib_send_wr write_wr; 294 struct ib_sge *sge; 295 int xdr_sge_no; 296 int sge_no; 297 int sge_bytes; 298 int sge_off; 299 int bc; 300 struct svc_rdma_op_ctxt *ctxt; 301 302 BUG_ON(vec->count > RPCSVC_MAXPAGES); 303 dprintk("svcrdma: RDMA_WRITE rmr=%x, to=%llx, xdr_off=%d, " 304 "write_len=%d, vec->sge=%p, vec->count=%lu\n", 305 rmr, (unsigned long long)to, xdr_off, 306 write_len, vec->sge, vec->count); 307 308 ctxt = svc_rdma_get_context(xprt); 309 ctxt->direction = DMA_TO_DEVICE; 310 sge = ctxt->sge; 311 312 /* Find the SGE associated with xdr_off */ 313 for (bc = xdr_off, xdr_sge_no = 1; bc && xdr_sge_no < vec->count; 314 xdr_sge_no++) { 315 if (vec->sge[xdr_sge_no].iov_len > bc) 316 break; 317 bc -= vec->sge[xdr_sge_no].iov_len; 318 } 319 320 sge_off = bc; 321 bc = write_len; 322 sge_no = 0; 323 324 /* Copy the remaining SGE */ 325 while (bc != 0) { 326 sge_bytes = min_t(size_t, 327 bc, vec->sge[xdr_sge_no].iov_len-sge_off); 328 sge[sge_no].length = sge_bytes; 329 if (!vec->frmr) { 330 sge[sge_no].addr = 331 dma_map_xdr(xprt, &rqstp->rq_res, xdr_off, 332 sge_bytes, DMA_TO_DEVICE); 333 xdr_off += sge_bytes; 334 if (ib_dma_mapping_error(xprt->sc_cm_id->device, 335 sge[sge_no].addr)) 336 goto err; 337 atomic_inc(&xprt->sc_dma_used); 338 sge[sge_no].lkey = xprt->sc_dma_lkey; 339 } else { 340 sge[sge_no].addr = (unsigned long) 341 vec->sge[xdr_sge_no].iov_base + sge_off; 342 sge[sge_no].lkey = vec->frmr->mr->lkey; 343 } 344 ctxt->count++; 345 ctxt->frmr = vec->frmr; 346 sge_off = 0; 347 sge_no++; 348 xdr_sge_no++; 349 BUG_ON(xdr_sge_no > vec->count); 350 bc -= sge_bytes; 351 } 352 353 /* Prepare WRITE WR */ 354 memset(&write_wr, 0, sizeof write_wr); 355 ctxt->wr_op = IB_WR_RDMA_WRITE; 356 write_wr.wr_id = (unsigned long)ctxt; 357 write_wr.sg_list = &sge[0]; 358 write_wr.num_sge = sge_no; 359 write_wr.opcode = IB_WR_RDMA_WRITE; 360 write_wr.send_flags = IB_SEND_SIGNALED; 361 write_wr.wr.rdma.rkey = rmr; 362 write_wr.wr.rdma.remote_addr = to; 363 364 /* Post It */ 365 atomic_inc(&rdma_stat_write); 366 if (svc_rdma_send(xprt, &write_wr)) 367 goto err; 368 return 0; 369 err: 370 svc_rdma_unmap_dma(ctxt); 371 svc_rdma_put_frmr(xprt, vec->frmr); 372 svc_rdma_put_context(ctxt, 0); 373 /* Fatal error, close transport */ 374 return -EIO; 375 } 376 377 static int send_write_chunks(struct svcxprt_rdma *xprt, 378 struct rpcrdma_msg *rdma_argp, 379 struct rpcrdma_msg *rdma_resp, 380 struct svc_rqst *rqstp, 381 struct svc_rdma_req_map *vec) 382 { 383 u32 xfer_len = rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len; 384 int write_len; 385 int max_write; 386 u32 xdr_off; 387 int chunk_off; 388 int chunk_no; 389 struct rpcrdma_write_array *arg_ary; 390 struct rpcrdma_write_array *res_ary; 391 int ret; 392 393 arg_ary = svc_rdma_get_write_array(rdma_argp); 394 if (!arg_ary) 395 return 0; 396 res_ary = (struct rpcrdma_write_array *) 397 &rdma_resp->rm_body.rm_chunks[1]; 398 399 if (vec->frmr) 400 max_write = vec->frmr->map_len; 401 else 402 max_write = xprt->sc_max_sge * PAGE_SIZE; 403 404 /* Write chunks start at the pagelist */ 405 for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0; 406 xfer_len && chunk_no < arg_ary->wc_nchunks; 407 chunk_no++) { 408 struct rpcrdma_segment *arg_ch; 409 u64 rs_offset; 410 411 arg_ch = &arg_ary->wc_array[chunk_no].wc_target; 412 write_len = min(xfer_len, arg_ch->rs_length); 413 414 /* Prepare the response chunk given the length actually 415 * written */ 416 rs_offset = get_unaligned(&(arg_ch->rs_offset)); 417 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, 418 arg_ch->rs_handle, 419 rs_offset, 420 write_len); 421 chunk_off = 0; 422 while (write_len) { 423 int this_write; 424 this_write = min(write_len, max_write); 425 ret = send_write(xprt, rqstp, 426 arg_ch->rs_handle, 427 rs_offset + chunk_off, 428 xdr_off, 429 this_write, 430 vec); 431 if (ret) { 432 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n", 433 ret); 434 return -EIO; 435 } 436 chunk_off += this_write; 437 xdr_off += this_write; 438 xfer_len -= this_write; 439 write_len -= this_write; 440 } 441 } 442 /* Update the req with the number of chunks actually used */ 443 svc_rdma_xdr_encode_write_list(rdma_resp, chunk_no); 444 445 return rqstp->rq_res.page_len + rqstp->rq_res.tail[0].iov_len; 446 } 447 448 static int send_reply_chunks(struct svcxprt_rdma *xprt, 449 struct rpcrdma_msg *rdma_argp, 450 struct rpcrdma_msg *rdma_resp, 451 struct svc_rqst *rqstp, 452 struct svc_rdma_req_map *vec) 453 { 454 u32 xfer_len = rqstp->rq_res.len; 455 int write_len; 456 int max_write; 457 u32 xdr_off; 458 int chunk_no; 459 int chunk_off; 460 struct rpcrdma_segment *ch; 461 struct rpcrdma_write_array *arg_ary; 462 struct rpcrdma_write_array *res_ary; 463 int ret; 464 465 arg_ary = svc_rdma_get_reply_array(rdma_argp); 466 if (!arg_ary) 467 return 0; 468 /* XXX: need to fix when reply lists occur with read-list and or 469 * write-list */ 470 res_ary = (struct rpcrdma_write_array *) 471 &rdma_resp->rm_body.rm_chunks[2]; 472 473 if (vec->frmr) 474 max_write = vec->frmr->map_len; 475 else 476 max_write = xprt->sc_max_sge * PAGE_SIZE; 477 478 /* xdr offset starts at RPC message */ 479 for (xdr_off = 0, chunk_no = 0; 480 xfer_len && chunk_no < arg_ary->wc_nchunks; 481 chunk_no++) { 482 u64 rs_offset; 483 ch = &arg_ary->wc_array[chunk_no].wc_target; 484 write_len = min(xfer_len, ch->rs_length); 485 486 /* Prepare the reply chunk given the length actually 487 * written */ 488 rs_offset = get_unaligned(&(ch->rs_offset)); 489 svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, 490 ch->rs_handle, rs_offset, 491 write_len); 492 chunk_off = 0; 493 while (write_len) { 494 int this_write; 495 496 this_write = min(write_len, max_write); 497 ret = send_write(xprt, rqstp, 498 ch->rs_handle, 499 rs_offset + chunk_off, 500 xdr_off, 501 this_write, 502 vec); 503 if (ret) { 504 dprintk("svcrdma: RDMA_WRITE failed, ret=%d\n", 505 ret); 506 return -EIO; 507 } 508 chunk_off += this_write; 509 xdr_off += this_write; 510 xfer_len -= this_write; 511 write_len -= this_write; 512 } 513 } 514 /* Update the req with the number of chunks actually used */ 515 svc_rdma_xdr_encode_reply_array(res_ary, chunk_no); 516 517 return rqstp->rq_res.len; 518 } 519 520 /* This function prepares the portion of the RPCRDMA message to be 521 * sent in the RDMA_SEND. This function is called after data sent via 522 * RDMA has already been transmitted. There are three cases: 523 * - The RPCRDMA header, RPC header, and payload are all sent in a 524 * single RDMA_SEND. This is the "inline" case. 525 * - The RPCRDMA header and some portion of the RPC header and data 526 * are sent via this RDMA_SEND and another portion of the data is 527 * sent via RDMA. 528 * - The RPCRDMA header [NOMSG] is sent in this RDMA_SEND and the RPC 529 * header and data are all transmitted via RDMA. 530 * In all three cases, this function prepares the RPCRDMA header in 531 * sge[0], the 'type' parameter indicates the type to place in the 532 * RPCRDMA header, and the 'byte_count' field indicates how much of 533 * the XDR to include in this RDMA_SEND. NB: The offset of the payload 534 * to send is zero in the XDR. 535 */ 536 static int send_reply(struct svcxprt_rdma *rdma, 537 struct svc_rqst *rqstp, 538 struct page *page, 539 struct rpcrdma_msg *rdma_resp, 540 struct svc_rdma_op_ctxt *ctxt, 541 struct svc_rdma_req_map *vec, 542 int byte_count) 543 { 544 struct ib_send_wr send_wr; 545 struct ib_send_wr inv_wr; 546 int sge_no; 547 int sge_bytes; 548 int page_no; 549 int ret; 550 551 /* Post a recv buffer to handle another request. */ 552 ret = svc_rdma_post_recv(rdma); 553 if (ret) { 554 printk(KERN_INFO 555 "svcrdma: could not post a receive buffer, err=%d." 556 "Closing transport %p.\n", ret, rdma); 557 set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags); 558 svc_rdma_put_frmr(rdma, vec->frmr); 559 svc_rdma_put_context(ctxt, 0); 560 return -ENOTCONN; 561 } 562 563 /* Prepare the context */ 564 ctxt->pages[0] = page; 565 ctxt->count = 1; 566 ctxt->frmr = vec->frmr; 567 if (vec->frmr) 568 set_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags); 569 else 570 clear_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags); 571 572 /* Prepare the SGE for the RPCRDMA Header */ 573 ctxt->sge[0].lkey = rdma->sc_dma_lkey; 574 ctxt->sge[0].length = svc_rdma_xdr_get_reply_hdr_len(rdma_resp); 575 ctxt->sge[0].addr = 576 ib_dma_map_page(rdma->sc_cm_id->device, page, 0, 577 ctxt->sge[0].length, DMA_TO_DEVICE); 578 if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr)) 579 goto err; 580 atomic_inc(&rdma->sc_dma_used); 581 582 ctxt->direction = DMA_TO_DEVICE; 583 584 /* Map the payload indicated by 'byte_count' */ 585 for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) { 586 int xdr_off = 0; 587 sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count); 588 byte_count -= sge_bytes; 589 if (!vec->frmr) { 590 ctxt->sge[sge_no].addr = 591 dma_map_xdr(rdma, &rqstp->rq_res, xdr_off, 592 sge_bytes, DMA_TO_DEVICE); 593 xdr_off += sge_bytes; 594 if (ib_dma_mapping_error(rdma->sc_cm_id->device, 595 ctxt->sge[sge_no].addr)) 596 goto err; 597 atomic_inc(&rdma->sc_dma_used); 598 ctxt->sge[sge_no].lkey = rdma->sc_dma_lkey; 599 } else { 600 ctxt->sge[sge_no].addr = (unsigned long) 601 vec->sge[sge_no].iov_base; 602 ctxt->sge[sge_no].lkey = vec->frmr->mr->lkey; 603 } 604 ctxt->sge[sge_no].length = sge_bytes; 605 } 606 BUG_ON(byte_count != 0); 607 608 /* Save all respages in the ctxt and remove them from the 609 * respages array. They are our pages until the I/O 610 * completes. 611 */ 612 for (page_no = 0; page_no < rqstp->rq_resused; page_no++) { 613 ctxt->pages[page_no+1] = rqstp->rq_respages[page_no]; 614 ctxt->count++; 615 rqstp->rq_respages[page_no] = NULL; 616 /* 617 * If there are more pages than SGE, terminate SGE 618 * list so that svc_rdma_unmap_dma doesn't attempt to 619 * unmap garbage. 620 */ 621 if (page_no+1 >= sge_no) 622 ctxt->sge[page_no+1].length = 0; 623 } 624 BUG_ON(sge_no > rdma->sc_max_sge); 625 memset(&send_wr, 0, sizeof send_wr); 626 ctxt->wr_op = IB_WR_SEND; 627 send_wr.wr_id = (unsigned long)ctxt; 628 send_wr.sg_list = ctxt->sge; 629 send_wr.num_sge = sge_no; 630 send_wr.opcode = IB_WR_SEND; 631 send_wr.send_flags = IB_SEND_SIGNALED; 632 if (vec->frmr) { 633 /* Prepare INVALIDATE WR */ 634 memset(&inv_wr, 0, sizeof inv_wr); 635 inv_wr.opcode = IB_WR_LOCAL_INV; 636 inv_wr.send_flags = IB_SEND_SIGNALED; 637 inv_wr.ex.invalidate_rkey = 638 vec->frmr->mr->lkey; 639 send_wr.next = &inv_wr; 640 } 641 642 ret = svc_rdma_send(rdma, &send_wr); 643 if (ret) 644 goto err; 645 646 return 0; 647 648 err: 649 svc_rdma_unmap_dma(ctxt); 650 svc_rdma_put_frmr(rdma, vec->frmr); 651 svc_rdma_put_context(ctxt, 1); 652 return -EIO; 653 } 654 655 void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp) 656 { 657 } 658 659 /* 660 * Return the start of an xdr buffer. 661 */ 662 static void *xdr_start(struct xdr_buf *xdr) 663 { 664 return xdr->head[0].iov_base - 665 (xdr->len - 666 xdr->page_len - 667 xdr->tail[0].iov_len - 668 xdr->head[0].iov_len); 669 } 670 671 int svc_rdma_sendto(struct svc_rqst *rqstp) 672 { 673 struct svc_xprt *xprt = rqstp->rq_xprt; 674 struct svcxprt_rdma *rdma = 675 container_of(xprt, struct svcxprt_rdma, sc_xprt); 676 struct rpcrdma_msg *rdma_argp; 677 struct rpcrdma_msg *rdma_resp; 678 struct rpcrdma_write_array *reply_ary; 679 enum rpcrdma_proc reply_type; 680 int ret; 681 int inline_bytes; 682 struct page *res_page; 683 struct svc_rdma_op_ctxt *ctxt; 684 struct svc_rdma_req_map *vec; 685 686 dprintk("svcrdma: sending response for rqstp=%p\n", rqstp); 687 688 /* Get the RDMA request header. */ 689 rdma_argp = xdr_start(&rqstp->rq_arg); 690 691 /* Build an req vec for the XDR */ 692 ctxt = svc_rdma_get_context(rdma); 693 ctxt->direction = DMA_TO_DEVICE; 694 vec = svc_rdma_get_req_map(); 695 ret = map_xdr(rdma, &rqstp->rq_res, vec); 696 if (ret) 697 goto err0; 698 inline_bytes = rqstp->rq_res.len; 699 700 /* Create the RDMA response header */ 701 res_page = svc_rdma_get_page(); 702 rdma_resp = page_address(res_page); 703 reply_ary = svc_rdma_get_reply_array(rdma_argp); 704 if (reply_ary) 705 reply_type = RDMA_NOMSG; 706 else 707 reply_type = RDMA_MSG; 708 svc_rdma_xdr_encode_reply_header(rdma, rdma_argp, 709 rdma_resp, reply_type); 710 711 /* Send any write-chunk data and build resp write-list */ 712 ret = send_write_chunks(rdma, rdma_argp, rdma_resp, 713 rqstp, vec); 714 if (ret < 0) { 715 printk(KERN_ERR "svcrdma: failed to send write chunks, rc=%d\n", 716 ret); 717 goto err1; 718 } 719 inline_bytes -= ret; 720 721 /* Send any reply-list data and update resp reply-list */ 722 ret = send_reply_chunks(rdma, rdma_argp, rdma_resp, 723 rqstp, vec); 724 if (ret < 0) { 725 printk(KERN_ERR "svcrdma: failed to send reply chunks, rc=%d\n", 726 ret); 727 goto err1; 728 } 729 inline_bytes -= ret; 730 731 ret = send_reply(rdma, rqstp, res_page, rdma_resp, ctxt, vec, 732 inline_bytes); 733 svc_rdma_put_req_map(vec); 734 dprintk("svcrdma: send_reply returns %d\n", ret); 735 return ret; 736 737 err1: 738 put_page(res_page); 739 err0: 740 svc_rdma_put_req_map(vec); 741 svc_rdma_put_context(ctxt, 0); 742 return ret; 743 } 744