1/* 2 * Copyright (c) 2014 Open Grid Computing, Inc. All rights reserved. 3 * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the BSD-type 9 * license below: 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 15 * Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 18 * Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials provided 21 * with the distribution. 22 * 23 * Neither the name of the Network Appliance, Inc. nor the names of 24 * its contributors may be used to endorse or promote products 25 * derived from this software without specific prior written 26 * permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 39 * 40 * Author: Tom Tucker <tom@opengridcomputing.com> 41 */ 42 43#include <linux/sunrpc/debug.h> 44#include <linux/sunrpc/rpc_rdma.h> 45#include <linux/spinlock.h> 46#include <linux/highmem.h> 47#include <asm/unaligned.h> 48#include <rdma/ib_verbs.h> 49#include <rdma/rdma_cm.h> 50#include <linux/sunrpc/svc_rdma.h> 51 52#define RPCDBG_FACILITY RPCDBG_SVCXPRT 53 54/* 55 * Replace the pages in the rq_argpages array with the pages from the SGE in 56 * the RDMA_RECV completion. The SGL should contain full pages up until the 57 * last one. 58 */ 59static void rdma_build_arg_xdr(struct svc_rqst *rqstp, 60 struct svc_rdma_op_ctxt *ctxt, 61 u32 byte_count) 62{ 63 struct page *page; 64 u32 bc; 65 int sge_no; 66 67 /* Swap the page in the SGE with the page in argpages */ 68 page = ctxt->pages[0]; 69 put_page(rqstp->rq_pages[0]); 70 rqstp->rq_pages[0] = page; 71 72 /* Set up the XDR head */ 73 rqstp->rq_arg.head[0].iov_base = page_address(page); 74 rqstp->rq_arg.head[0].iov_len = 75 min_t(size_t, byte_count, ctxt->sge[0].length); 76 rqstp->rq_arg.len = byte_count; 77 rqstp->rq_arg.buflen = byte_count; 78 79 /* Compute bytes past head in the SGL */ 80 bc = byte_count - rqstp->rq_arg.head[0].iov_len; 81 82 /* If data remains, store it in the pagelist */ 83 rqstp->rq_arg.page_len = bc; 84 rqstp->rq_arg.page_base = 0; 85 rqstp->rq_arg.pages = &rqstp->rq_pages[1]; 86 sge_no = 1; 87 while (bc && sge_no < ctxt->count) { 88 page = ctxt->pages[sge_no]; 89 put_page(rqstp->rq_pages[sge_no]); 90 rqstp->rq_pages[sge_no] = page; 91 bc -= min_t(u32, bc, ctxt->sge[sge_no].length); 92 rqstp->rq_arg.buflen += ctxt->sge[sge_no].length; 93 sge_no++; 94 } 95 rqstp->rq_respages = &rqstp->rq_pages[sge_no]; 96 rqstp->rq_next_page = rqstp->rq_respages + 1; 97 98 /* We should never run out of SGE because the limit is defined to 99 * support the max allowed RPC data length 100 */ 101 BUG_ON(bc && (sge_no == ctxt->count)); 102 BUG_ON((rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_len) 103 != byte_count); 104 BUG_ON(rqstp->rq_arg.len != byte_count); 105 106 /* If not all pages were used from the SGL, free the remaining ones */ 107 bc = sge_no; 108 while (sge_no < ctxt->count) { 109 page = ctxt->pages[sge_no++]; 110 put_page(page); 111 } 112 ctxt->count = bc; 113 114 /* Set up tail */ 115 rqstp->rq_arg.tail[0].iov_base = NULL; 116 rqstp->rq_arg.tail[0].iov_len = 0; 117} 118 119static int rdma_read_max_sge(struct svcxprt_rdma *xprt, int sge_count) 120{ 121 if (rdma_node_get_transport(xprt->sc_cm_id->device->node_type) == 122 RDMA_TRANSPORT_IWARP) 123 return 1; 124 else 125 return min_t(int, sge_count, xprt->sc_max_sge); 126} 127 128typedef int (*rdma_reader_fn)(struct svcxprt_rdma *xprt, 129 struct svc_rqst *rqstp, 130 struct svc_rdma_op_ctxt *head, 131 int *page_no, 132 u32 *page_offset, 133 u32 rs_handle, 134 u32 rs_length, 135 u64 rs_offset, 136 int last); 137 138/* Issue an RDMA_READ using the local lkey to map the data sink */ 139static int rdma_read_chunk_lcl(struct svcxprt_rdma *xprt, 140 struct svc_rqst *rqstp, 141 struct svc_rdma_op_ctxt *head, 142 int *page_no, 143 u32 *page_offset, 144 u32 rs_handle, 145 u32 rs_length, 146 u64 rs_offset, 147 int last) 148{ 149 struct ib_send_wr read_wr; 150 int pages_needed = PAGE_ALIGN(*page_offset + rs_length) >> PAGE_SHIFT; 151 struct svc_rdma_op_ctxt *ctxt = svc_rdma_get_context(xprt); 152 int ret, read, pno; 153 u32 pg_off = *page_offset; 154 u32 pg_no = *page_no; 155 156 ctxt->direction = DMA_FROM_DEVICE; 157 ctxt->read_hdr = head; 158 pages_needed = 159 min_t(int, pages_needed, rdma_read_max_sge(xprt, pages_needed)); 160 read = min_t(int, pages_needed << PAGE_SHIFT, rs_length); 161 162 for (pno = 0; pno < pages_needed; pno++) { 163 int len = min_t(int, rs_length, PAGE_SIZE - pg_off); 164 165 head->arg.pages[pg_no] = rqstp->rq_arg.pages[pg_no]; 166 head->arg.page_len += len; 167 head->arg.len += len; 168 if (!pg_off) 169 head->count++; 170 rqstp->rq_respages = &rqstp->rq_arg.pages[pg_no+1]; 171 rqstp->rq_next_page = rqstp->rq_respages + 1; 172 ctxt->sge[pno].addr = 173 ib_dma_map_page(xprt->sc_cm_id->device, 174 head->arg.pages[pg_no], pg_off, 175 PAGE_SIZE - pg_off, 176 DMA_FROM_DEVICE); 177 ret = ib_dma_mapping_error(xprt->sc_cm_id->device, 178 ctxt->sge[pno].addr); 179 if (ret) 180 goto err; 181 atomic_inc(&xprt->sc_dma_used); 182 183 /* The lkey here is either a local dma lkey or a dma_mr lkey */ 184 ctxt->sge[pno].lkey = xprt->sc_dma_lkey; 185 ctxt->sge[pno].length = len; 186 ctxt->count++; 187 188 /* adjust offset and wrap to next page if needed */ 189 pg_off += len; 190 if (pg_off == PAGE_SIZE) { 191 pg_off = 0; 192 pg_no++; 193 } 194 rs_length -= len; 195 } 196 197 if (last && rs_length == 0) 198 set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); 199 else 200 clear_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); 201 202 memset(&read_wr, 0, sizeof(read_wr)); 203 read_wr.wr_id = (unsigned long)ctxt; 204 read_wr.opcode = IB_WR_RDMA_READ; 205 ctxt->wr_op = read_wr.opcode; 206 read_wr.send_flags = IB_SEND_SIGNALED; 207 read_wr.wr.rdma.rkey = rs_handle; 208 read_wr.wr.rdma.remote_addr = rs_offset; 209 read_wr.sg_list = ctxt->sge; 210 read_wr.num_sge = pages_needed; 211 212 ret = svc_rdma_send(xprt, &read_wr); 213 if (ret) { 214 pr_err("svcrdma: Error %d posting RDMA_READ\n", ret); 215 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 216 goto err; 217 } 218 219 /* return current location in page array */ 220 *page_no = pg_no; 221 *page_offset = pg_off; 222 ret = read; 223 atomic_inc(&rdma_stat_read); 224 return ret; 225 err: 226 svc_rdma_unmap_dma(ctxt); 227 svc_rdma_put_context(ctxt, 0); 228 return ret; 229} 230 231/* Issue an RDMA_READ using an FRMR to map the data sink */ 232static int rdma_read_chunk_frmr(struct svcxprt_rdma *xprt, 233 struct svc_rqst *rqstp, 234 struct svc_rdma_op_ctxt *head, 235 int *page_no, 236 u32 *page_offset, 237 u32 rs_handle, 238 u32 rs_length, 239 u64 rs_offset, 240 int last) 241{ 242 struct ib_send_wr read_wr; 243 struct ib_send_wr inv_wr; 244 struct ib_send_wr fastreg_wr; 245 u8 key; 246 int pages_needed = PAGE_ALIGN(*page_offset + rs_length) >> PAGE_SHIFT; 247 struct svc_rdma_op_ctxt *ctxt = svc_rdma_get_context(xprt); 248 struct svc_rdma_fastreg_mr *frmr = svc_rdma_get_frmr(xprt); 249 int ret, read, pno; 250 u32 pg_off = *page_offset; 251 u32 pg_no = *page_no; 252 253 if (IS_ERR(frmr)) 254 return -ENOMEM; 255 256 ctxt->direction = DMA_FROM_DEVICE; 257 ctxt->frmr = frmr; 258 pages_needed = min_t(int, pages_needed, xprt->sc_frmr_pg_list_len); 259 read = min_t(int, pages_needed << PAGE_SHIFT, rs_length); 260 261 frmr->kva = page_address(rqstp->rq_arg.pages[pg_no]); 262 frmr->direction = DMA_FROM_DEVICE; 263 frmr->access_flags = (IB_ACCESS_LOCAL_WRITE|IB_ACCESS_REMOTE_WRITE); 264 frmr->map_len = pages_needed << PAGE_SHIFT; 265 frmr->page_list_len = pages_needed; 266 267 for (pno = 0; pno < pages_needed; pno++) { 268 int len = min_t(int, rs_length, PAGE_SIZE - pg_off); 269 270 head->arg.pages[pg_no] = rqstp->rq_arg.pages[pg_no]; 271 head->arg.page_len += len; 272 head->arg.len += len; 273 if (!pg_off) 274 head->count++; 275 rqstp->rq_respages = &rqstp->rq_arg.pages[pg_no+1]; 276 rqstp->rq_next_page = rqstp->rq_respages + 1; 277 frmr->page_list->page_list[pno] = 278 ib_dma_map_page(xprt->sc_cm_id->device, 279 head->arg.pages[pg_no], 0, 280 PAGE_SIZE, DMA_FROM_DEVICE); 281 ret = ib_dma_mapping_error(xprt->sc_cm_id->device, 282 frmr->page_list->page_list[pno]); 283 if (ret) 284 goto err; 285 atomic_inc(&xprt->sc_dma_used); 286 287 /* adjust offset and wrap to next page if needed */ 288 pg_off += len; 289 if (pg_off == PAGE_SIZE) { 290 pg_off = 0; 291 pg_no++; 292 } 293 rs_length -= len; 294 } 295 296 if (last && rs_length == 0) 297 set_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); 298 else 299 clear_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags); 300 301 /* Bump the key */ 302 key = (u8)(frmr->mr->lkey & 0x000000FF); 303 ib_update_fast_reg_key(frmr->mr, ++key); 304 305 ctxt->sge[0].addr = (unsigned long)frmr->kva + *page_offset; 306 ctxt->sge[0].lkey = frmr->mr->lkey; 307 ctxt->sge[0].length = read; 308 ctxt->count = 1; 309 ctxt->read_hdr = head; 310 311 /* Prepare FASTREG WR */ 312 memset(&fastreg_wr, 0, sizeof(fastreg_wr)); 313 fastreg_wr.opcode = IB_WR_FAST_REG_MR; 314 fastreg_wr.send_flags = IB_SEND_SIGNALED; 315 fastreg_wr.wr.fast_reg.iova_start = (unsigned long)frmr->kva; 316 fastreg_wr.wr.fast_reg.page_list = frmr->page_list; 317 fastreg_wr.wr.fast_reg.page_list_len = frmr->page_list_len; 318 fastreg_wr.wr.fast_reg.page_shift = PAGE_SHIFT; 319 fastreg_wr.wr.fast_reg.length = frmr->map_len; 320 fastreg_wr.wr.fast_reg.access_flags = frmr->access_flags; 321 fastreg_wr.wr.fast_reg.rkey = frmr->mr->lkey; 322 fastreg_wr.next = &read_wr; 323 324 /* Prepare RDMA_READ */ 325 memset(&read_wr, 0, sizeof(read_wr)); 326 read_wr.send_flags = IB_SEND_SIGNALED; 327 read_wr.wr.rdma.rkey = rs_handle; 328 read_wr.wr.rdma.remote_addr = rs_offset; 329 read_wr.sg_list = ctxt->sge; 330 read_wr.num_sge = 1; 331 if (xprt->sc_dev_caps & SVCRDMA_DEVCAP_READ_W_INV) { 332 read_wr.opcode = IB_WR_RDMA_READ_WITH_INV; 333 read_wr.wr_id = (unsigned long)ctxt; 334 read_wr.ex.invalidate_rkey = ctxt->frmr->mr->lkey; 335 } else { 336 read_wr.opcode = IB_WR_RDMA_READ; 337 read_wr.next = &inv_wr; 338 /* Prepare invalidate */ 339 memset(&inv_wr, 0, sizeof(inv_wr)); 340 inv_wr.wr_id = (unsigned long)ctxt; 341 inv_wr.opcode = IB_WR_LOCAL_INV; 342 inv_wr.send_flags = IB_SEND_SIGNALED | IB_SEND_FENCE; 343 inv_wr.ex.invalidate_rkey = frmr->mr->lkey; 344 } 345 ctxt->wr_op = read_wr.opcode; 346 347 /* Post the chain */ 348 ret = svc_rdma_send(xprt, &fastreg_wr); 349 if (ret) { 350 pr_err("svcrdma: Error %d posting RDMA_READ\n", ret); 351 set_bit(XPT_CLOSE, &xprt->sc_xprt.xpt_flags); 352 goto err; 353 } 354 355 /* return current location in page array */ 356 *page_no = pg_no; 357 *page_offset = pg_off; 358 ret = read; 359 atomic_inc(&rdma_stat_read); 360 return ret; 361 err: 362 svc_rdma_unmap_dma(ctxt); 363 svc_rdma_put_context(ctxt, 0); 364 svc_rdma_put_frmr(xprt, frmr); 365 return ret; 366} 367 368static int rdma_read_chunks(struct svcxprt_rdma *xprt, 369 struct rpcrdma_msg *rmsgp, 370 struct svc_rqst *rqstp, 371 struct svc_rdma_op_ctxt *head) 372{ 373 int page_no, ch_count, ret; 374 struct rpcrdma_read_chunk *ch; 375 u32 page_offset, byte_count; 376 u64 rs_offset; 377 rdma_reader_fn reader; 378 379 /* If no read list is present, return 0 */ 380 ch = svc_rdma_get_read_chunk(rmsgp); 381 if (!ch) 382 return 0; 383 384 svc_rdma_rcl_chunk_counts(ch, &ch_count, &byte_count); 385 if (ch_count > RPCSVC_MAXPAGES) 386 return -EINVAL; 387 388 /* The request is completed when the RDMA_READs complete. The 389 * head context keeps all the pages that comprise the 390 * request. 391 */ 392 head->arg.head[0] = rqstp->rq_arg.head[0]; 393 head->arg.tail[0] = rqstp->rq_arg.tail[0]; 394 head->arg.pages = &head->pages[head->count]; 395 head->hdr_count = head->count; 396 head->arg.page_base = 0; 397 head->arg.page_len = 0; 398 head->arg.len = rqstp->rq_arg.len; 399 head->arg.buflen = rqstp->rq_arg.buflen; 400 401 /* Use FRMR if supported */ 402 if (xprt->sc_dev_caps & SVCRDMA_DEVCAP_FAST_REG) 403 reader = rdma_read_chunk_frmr; 404 else 405 reader = rdma_read_chunk_lcl; 406 407 page_no = 0; page_offset = 0; 408 for (ch = (struct rpcrdma_read_chunk *)&rmsgp->rm_body.rm_chunks[0]; 409 ch->rc_discrim != 0; ch++) { 410 411 xdr_decode_hyper((__be32 *)&ch->rc_target.rs_offset, 412 &rs_offset); 413 byte_count = ntohl(ch->rc_target.rs_length); 414 415 while (byte_count > 0) { 416 ret = reader(xprt, rqstp, head, 417 &page_no, &page_offset, 418 ntohl(ch->rc_target.rs_handle), 419 byte_count, rs_offset, 420 ((ch+1)->rc_discrim == 0) /* last */ 421 ); 422 if (ret < 0) 423 goto err; 424 byte_count -= ret; 425 rs_offset += ret; 426 head->arg.buflen += ret; 427 } 428 } 429 ret = 1; 430 err: 431 /* Detach arg pages. svc_recv will replenish them */ 432 for (page_no = 0; 433 &rqstp->rq_pages[page_no] < rqstp->rq_respages; page_no++) 434 rqstp->rq_pages[page_no] = NULL; 435 436 return ret; 437} 438 439/* 440 * To avoid a separate RDMA READ just for a handful of zero bytes, 441 * RFC 5666 section 3.7 allows the client to omit the XDR zero pad 442 * in chunk lists. 443 */ 444static void 445rdma_fix_xdr_pad(struct xdr_buf *buf) 446{ 447 unsigned int page_len = buf->page_len; 448 unsigned int size = (XDR_QUADLEN(page_len) << 2) - page_len; 449 unsigned int offset, pg_no; 450 char *p; 451 452 if (size == 0) 453 return; 454 455 pg_no = page_len >> PAGE_SHIFT; 456 offset = page_len & ~PAGE_MASK; 457 p = page_address(buf->pages[pg_no]); 458 memset(p + offset, 0, size); 459 460 buf->page_len += size; 461 buf->buflen += size; 462 buf->len += size; 463} 464 465static int rdma_read_complete(struct svc_rqst *rqstp, 466 struct svc_rdma_op_ctxt *head) 467{ 468 int page_no; 469 int ret; 470 471 BUG_ON(!head); 472 473 /* Copy RPC pages */ 474 for (page_no = 0; page_no < head->count; page_no++) { 475 put_page(rqstp->rq_pages[page_no]); 476 rqstp->rq_pages[page_no] = head->pages[page_no]; 477 } 478 /* Point rq_arg.pages past header */ 479 rdma_fix_xdr_pad(&head->arg); 480 rqstp->rq_arg.pages = &rqstp->rq_pages[head->hdr_count]; 481 rqstp->rq_arg.page_len = head->arg.page_len; 482 rqstp->rq_arg.page_base = head->arg.page_base; 483 484 /* rq_respages starts after the last arg page */ 485 rqstp->rq_respages = &rqstp->rq_arg.pages[page_no]; 486 rqstp->rq_next_page = rqstp->rq_respages + 1; 487 488 /* Rebuild rq_arg head and tail. */ 489 rqstp->rq_arg.head[0] = head->arg.head[0]; 490 rqstp->rq_arg.tail[0] = head->arg.tail[0]; 491 rqstp->rq_arg.len = head->arg.len; 492 rqstp->rq_arg.buflen = head->arg.buflen; 493 494 /* Free the context */ 495 svc_rdma_put_context(head, 0); 496 497 /* XXX: What should this be? */ 498 rqstp->rq_prot = IPPROTO_MAX; 499 svc_xprt_copy_addrs(rqstp, rqstp->rq_xprt); 500 501 ret = rqstp->rq_arg.head[0].iov_len 502 + rqstp->rq_arg.page_len 503 + rqstp->rq_arg.tail[0].iov_len; 504 dprintk("svcrdma: deferred read ret=%d, rq_arg.len =%d, " 505 "rq_arg.head[0].iov_base=%p, rq_arg.head[0].iov_len = %zd\n", 506 ret, rqstp->rq_arg.len, rqstp->rq_arg.head[0].iov_base, 507 rqstp->rq_arg.head[0].iov_len); 508 509 return ret; 510} 511 512/* 513 * Set up the rqstp thread context to point to the RQ buffer. If 514 * necessary, pull additional data from the client with an RDMA_READ 515 * request. 516 */ 517int svc_rdma_recvfrom(struct svc_rqst *rqstp) 518{ 519 struct svc_xprt *xprt = rqstp->rq_xprt; 520 struct svcxprt_rdma *rdma_xprt = 521 container_of(xprt, struct svcxprt_rdma, sc_xprt); 522 struct svc_rdma_op_ctxt *ctxt = NULL; 523 struct rpcrdma_msg *rmsgp; 524 int ret = 0; 525 int len; 526 527 dprintk("svcrdma: rqstp=%p\n", rqstp); 528 529 spin_lock_bh(&rdma_xprt->sc_rq_dto_lock); 530 if (!list_empty(&rdma_xprt->sc_read_complete_q)) { 531 ctxt = list_entry(rdma_xprt->sc_read_complete_q.next, 532 struct svc_rdma_op_ctxt, 533 dto_q); 534 list_del_init(&ctxt->dto_q); 535 spin_unlock_bh(&rdma_xprt->sc_rq_dto_lock); 536 return rdma_read_complete(rqstp, ctxt); 537 } else if (!list_empty(&rdma_xprt->sc_rq_dto_q)) { 538 ctxt = list_entry(rdma_xprt->sc_rq_dto_q.next, 539 struct svc_rdma_op_ctxt, 540 dto_q); 541 list_del_init(&ctxt->dto_q); 542 } else { 543 atomic_inc(&rdma_stat_rq_starve); 544 clear_bit(XPT_DATA, &xprt->xpt_flags); 545 ctxt = NULL; 546 } 547 spin_unlock_bh(&rdma_xprt->sc_rq_dto_lock); 548 if (!ctxt) { 549 /* This is the EAGAIN path. The svc_recv routine will 550 * return -EAGAIN, the nfsd thread will go to call into 551 * svc_recv again and we shouldn't be on the active 552 * transport list 553 */ 554 if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) 555 goto close_out; 556 557 goto out; 558 } 559 dprintk("svcrdma: processing ctxt=%p on xprt=%p, rqstp=%p, status=%d\n", 560 ctxt, rdma_xprt, rqstp, ctxt->wc_status); 561 BUG_ON(ctxt->wc_status != IB_WC_SUCCESS); 562 atomic_inc(&rdma_stat_recv); 563 564 /* Build up the XDR from the receive buffers. */ 565 rdma_build_arg_xdr(rqstp, ctxt, ctxt->byte_len); 566 567 /* Decode the RDMA header. */ 568 len = svc_rdma_xdr_decode_req(&rmsgp, rqstp); 569 rqstp->rq_xprt_hlen = len; 570 571 /* If the request is invalid, reply with an error */ 572 if (len < 0) { 573 if (len == -ENOSYS) 574 svc_rdma_send_error(rdma_xprt, rmsgp, ERR_VERS); 575 goto close_out; 576 } 577 578 /* Read read-list data. */ 579 ret = rdma_read_chunks(rdma_xprt, rmsgp, rqstp, ctxt); 580 if (ret > 0) { 581 /* read-list posted, defer until data received from client. */ 582 goto defer; 583 } else if (ret < 0) { 584 /* Post of read-list failed, free context. */ 585 svc_rdma_put_context(ctxt, 1); 586 return 0; 587 } 588 589 ret = rqstp->rq_arg.head[0].iov_len 590 + rqstp->rq_arg.page_len 591 + rqstp->rq_arg.tail[0].iov_len; 592 svc_rdma_put_context(ctxt, 0); 593 out: 594 dprintk("svcrdma: ret = %d, rq_arg.len =%d, " 595 "rq_arg.head[0].iov_base=%p, rq_arg.head[0].iov_len = %zd\n", 596 ret, rqstp->rq_arg.len, 597 rqstp->rq_arg.head[0].iov_base, 598 rqstp->rq_arg.head[0].iov_len); 599 rqstp->rq_prot = IPPROTO_MAX; 600 svc_xprt_copy_addrs(rqstp, xprt); 601 return ret; 602 603 close_out: 604 if (ctxt) 605 svc_rdma_put_context(ctxt, 1); 606 dprintk("svcrdma: transport %p is closing\n", xprt); 607 /* 608 * Set the close bit and enqueue it. svc_recv will see the 609 * close bit and call svc_xprt_delete 610 */ 611 set_bit(XPT_CLOSE, &xprt->xpt_flags); 612defer: 613 return 0; 614} 615