1 /* 2 * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved. 3 * Copyright (c) 2005, 2006 PathScale, 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 9 * OpenIB.org BSD license below: 10 * 11 * Redistribution and use in source and binary forms, with or 12 * without modification, are permitted provided that the following 13 * conditions are met: 14 * 15 * - Redistributions of source code must retain the above 16 * copyright notice, this list of conditions and the following 17 * disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials 22 * provided with the distribution. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 31 * SOFTWARE. 32 */ 33 34 #include <linux/io.h> 35 36 #include "qib.h" 37 38 /* cut down ridiculously long IB macro names */ 39 #define OP(x) IB_OPCODE_RC_##x 40 41 42 static u32 restart_sge(struct rvt_sge_state *ss, struct rvt_swqe *wqe, 43 u32 psn, u32 pmtu) 44 { 45 u32 len; 46 47 len = ((psn - wqe->psn) & QIB_PSN_MASK) * pmtu; 48 ss->sge = wqe->sg_list[0]; 49 ss->sg_list = wqe->sg_list + 1; 50 ss->num_sge = wqe->wr.num_sge; 51 ss->total_len = wqe->length; 52 rvt_skip_sge(ss, len, false); 53 return wqe->length - len; 54 } 55 56 /** 57 * qib_make_rc_ack - construct a response packet (ACK, NAK, or RDMA read) 58 * @dev: the device for this QP 59 * @qp: a pointer to the QP 60 * @ohdr: a pointer to the IB header being constructed 61 * @pmtu: the path MTU 62 * 63 * Return 1 if constructed; otherwise, return 0. 64 * Note that we are in the responder's side of the QP context. 65 * Note the QP s_lock must be held. 66 */ 67 static int qib_make_rc_ack(struct qib_ibdev *dev, struct rvt_qp *qp, 68 struct ib_other_headers *ohdr, u32 pmtu) 69 { 70 struct rvt_ack_entry *e; 71 u32 hwords; 72 u32 len; 73 u32 bth0; 74 u32 bth2; 75 76 /* Don't send an ACK if we aren't supposed to. */ 77 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) 78 goto bail; 79 80 /* header size in 32-bit words LRH+BTH = (8+12)/4. */ 81 hwords = 5; 82 83 switch (qp->s_ack_state) { 84 case OP(RDMA_READ_RESPONSE_LAST): 85 case OP(RDMA_READ_RESPONSE_ONLY): 86 e = &qp->s_ack_queue[qp->s_tail_ack_queue]; 87 if (e->rdma_sge.mr) { 88 rvt_put_mr(e->rdma_sge.mr); 89 e->rdma_sge.mr = NULL; 90 } 91 /* FALLTHROUGH */ 92 case OP(ATOMIC_ACKNOWLEDGE): 93 /* 94 * We can increment the tail pointer now that the last 95 * response has been sent instead of only being 96 * constructed. 97 */ 98 if (++qp->s_tail_ack_queue > QIB_MAX_RDMA_ATOMIC) 99 qp->s_tail_ack_queue = 0; 100 /* FALLTHROUGH */ 101 case OP(SEND_ONLY): 102 case OP(ACKNOWLEDGE): 103 /* Check for no next entry in the queue. */ 104 if (qp->r_head_ack_queue == qp->s_tail_ack_queue) { 105 if (qp->s_flags & RVT_S_ACK_PENDING) 106 goto normal; 107 goto bail; 108 } 109 110 e = &qp->s_ack_queue[qp->s_tail_ack_queue]; 111 if (e->opcode == OP(RDMA_READ_REQUEST)) { 112 /* 113 * If a RDMA read response is being resent and 114 * we haven't seen the duplicate request yet, 115 * then stop sending the remaining responses the 116 * responder has seen until the requester resends it. 117 */ 118 len = e->rdma_sge.sge_length; 119 if (len && !e->rdma_sge.mr) { 120 qp->s_tail_ack_queue = qp->r_head_ack_queue; 121 goto bail; 122 } 123 /* Copy SGE state in case we need to resend */ 124 qp->s_rdma_mr = e->rdma_sge.mr; 125 if (qp->s_rdma_mr) 126 rvt_get_mr(qp->s_rdma_mr); 127 qp->s_ack_rdma_sge.sge = e->rdma_sge; 128 qp->s_ack_rdma_sge.num_sge = 1; 129 qp->s_cur_sge = &qp->s_ack_rdma_sge; 130 if (len > pmtu) { 131 len = pmtu; 132 qp->s_ack_state = OP(RDMA_READ_RESPONSE_FIRST); 133 } else { 134 qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY); 135 e->sent = 1; 136 } 137 ohdr->u.aeth = rvt_compute_aeth(qp); 138 hwords++; 139 qp->s_ack_rdma_psn = e->psn; 140 bth2 = qp->s_ack_rdma_psn++ & QIB_PSN_MASK; 141 } else { 142 /* COMPARE_SWAP or FETCH_ADD */ 143 qp->s_cur_sge = NULL; 144 len = 0; 145 qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE); 146 ohdr->u.at.aeth = rvt_compute_aeth(qp); 147 ib_u64_put(e->atomic_data, &ohdr->u.at.atomic_ack_eth); 148 hwords += sizeof(ohdr->u.at) / sizeof(u32); 149 bth2 = e->psn & QIB_PSN_MASK; 150 e->sent = 1; 151 } 152 bth0 = qp->s_ack_state << 24; 153 break; 154 155 case OP(RDMA_READ_RESPONSE_FIRST): 156 qp->s_ack_state = OP(RDMA_READ_RESPONSE_MIDDLE); 157 /* FALLTHROUGH */ 158 case OP(RDMA_READ_RESPONSE_MIDDLE): 159 qp->s_cur_sge = &qp->s_ack_rdma_sge; 160 qp->s_rdma_mr = qp->s_ack_rdma_sge.sge.mr; 161 if (qp->s_rdma_mr) 162 rvt_get_mr(qp->s_rdma_mr); 163 len = qp->s_ack_rdma_sge.sge.sge_length; 164 if (len > pmtu) 165 len = pmtu; 166 else { 167 ohdr->u.aeth = rvt_compute_aeth(qp); 168 hwords++; 169 qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST); 170 e = &qp->s_ack_queue[qp->s_tail_ack_queue]; 171 e->sent = 1; 172 } 173 bth0 = qp->s_ack_state << 24; 174 bth2 = qp->s_ack_rdma_psn++ & QIB_PSN_MASK; 175 break; 176 177 default: 178 normal: 179 /* 180 * Send a regular ACK. 181 * Set the s_ack_state so we wait until after sending 182 * the ACK before setting s_ack_state to ACKNOWLEDGE 183 * (see above). 184 */ 185 qp->s_ack_state = OP(SEND_ONLY); 186 qp->s_flags &= ~RVT_S_ACK_PENDING; 187 qp->s_cur_sge = NULL; 188 if (qp->s_nak_state) 189 ohdr->u.aeth = 190 cpu_to_be32((qp->r_msn & IB_MSN_MASK) | 191 (qp->s_nak_state << 192 IB_AETH_CREDIT_SHIFT)); 193 else 194 ohdr->u.aeth = rvt_compute_aeth(qp); 195 hwords++; 196 len = 0; 197 bth0 = OP(ACKNOWLEDGE) << 24; 198 bth2 = qp->s_ack_psn & QIB_PSN_MASK; 199 } 200 qp->s_rdma_ack_cnt++; 201 qp->s_hdrwords = hwords; 202 qp->s_cur_size = len; 203 qib_make_ruc_header(qp, ohdr, bth0, bth2); 204 return 1; 205 206 bail: 207 qp->s_ack_state = OP(ACKNOWLEDGE); 208 qp->s_flags &= ~(RVT_S_RESP_PENDING | RVT_S_ACK_PENDING); 209 return 0; 210 } 211 212 /** 213 * qib_make_rc_req - construct a request packet (SEND, RDMA r/w, ATOMIC) 214 * @qp: a pointer to the QP 215 * 216 * Assumes the s_lock is held. 217 * 218 * Return 1 if constructed; otherwise, return 0. 219 */ 220 int qib_make_rc_req(struct rvt_qp *qp, unsigned long *flags) 221 { 222 struct qib_qp_priv *priv = qp->priv; 223 struct qib_ibdev *dev = to_idev(qp->ibqp.device); 224 struct ib_other_headers *ohdr; 225 struct rvt_sge_state *ss; 226 struct rvt_swqe *wqe; 227 u32 hwords; 228 u32 len; 229 u32 bth0; 230 u32 bth2; 231 u32 pmtu = qp->pmtu; 232 char newreq; 233 int ret = 0; 234 int delta; 235 236 ohdr = &priv->s_hdr->u.oth; 237 if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) 238 ohdr = &priv->s_hdr->u.l.oth; 239 240 /* Sending responses has higher priority over sending requests. */ 241 if ((qp->s_flags & RVT_S_RESP_PENDING) && 242 qib_make_rc_ack(dev, qp, ohdr, pmtu)) 243 goto done; 244 245 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) { 246 if (!(ib_rvt_state_ops[qp->state] & RVT_FLUSH_SEND)) 247 goto bail; 248 /* We are in the error state, flush the work request. */ 249 smp_read_barrier_depends(); /* see post_one_send() */ 250 if (qp->s_last == READ_ONCE(qp->s_head)) 251 goto bail; 252 /* If DMAs are in progress, we can't flush immediately. */ 253 if (atomic_read(&priv->s_dma_busy)) { 254 qp->s_flags |= RVT_S_WAIT_DMA; 255 goto bail; 256 } 257 wqe = rvt_get_swqe_ptr(qp, qp->s_last); 258 qib_send_complete(qp, wqe, qp->s_last != qp->s_acked ? 259 IB_WC_SUCCESS : IB_WC_WR_FLUSH_ERR); 260 /* will get called again */ 261 goto done; 262 } 263 264 if (qp->s_flags & (RVT_S_WAIT_RNR | RVT_S_WAIT_ACK)) 265 goto bail; 266 267 if (qib_cmp24(qp->s_psn, qp->s_sending_hpsn) <= 0) { 268 if (qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0) { 269 qp->s_flags |= RVT_S_WAIT_PSN; 270 goto bail; 271 } 272 qp->s_sending_psn = qp->s_psn; 273 qp->s_sending_hpsn = qp->s_psn - 1; 274 } 275 276 /* header size in 32-bit words LRH+BTH = (8+12)/4. */ 277 hwords = 5; 278 bth0 = 0; 279 280 /* Send a request. */ 281 wqe = rvt_get_swqe_ptr(qp, qp->s_cur); 282 switch (qp->s_state) { 283 default: 284 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_NEXT_SEND_OK)) 285 goto bail; 286 /* 287 * Resend an old request or start a new one. 288 * 289 * We keep track of the current SWQE so that 290 * we don't reset the "furthest progress" state 291 * if we need to back up. 292 */ 293 newreq = 0; 294 if (qp->s_cur == qp->s_tail) { 295 /* Check if send work queue is empty. */ 296 smp_read_barrier_depends(); /* see post_one_send() */ 297 if (qp->s_tail == READ_ONCE(qp->s_head)) 298 goto bail; 299 /* 300 * If a fence is requested, wait for previous 301 * RDMA read and atomic operations to finish. 302 */ 303 if ((wqe->wr.send_flags & IB_SEND_FENCE) && 304 qp->s_num_rd_atomic) { 305 qp->s_flags |= RVT_S_WAIT_FENCE; 306 goto bail; 307 } 308 newreq = 1; 309 qp->s_psn = wqe->psn; 310 } 311 /* 312 * Note that we have to be careful not to modify the 313 * original work request since we may need to resend 314 * it. 315 */ 316 len = wqe->length; 317 ss = &qp->s_sge; 318 bth2 = qp->s_psn & QIB_PSN_MASK; 319 switch (wqe->wr.opcode) { 320 case IB_WR_SEND: 321 case IB_WR_SEND_WITH_IMM: 322 /* If no credit, return. */ 323 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) && 324 rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) { 325 qp->s_flags |= RVT_S_WAIT_SSN_CREDIT; 326 goto bail; 327 } 328 if (len > pmtu) { 329 qp->s_state = OP(SEND_FIRST); 330 len = pmtu; 331 break; 332 } 333 if (wqe->wr.opcode == IB_WR_SEND) 334 qp->s_state = OP(SEND_ONLY); 335 else { 336 qp->s_state = OP(SEND_ONLY_WITH_IMMEDIATE); 337 /* Immediate data comes after the BTH */ 338 ohdr->u.imm_data = wqe->wr.ex.imm_data; 339 hwords += 1; 340 } 341 if (wqe->wr.send_flags & IB_SEND_SOLICITED) 342 bth0 |= IB_BTH_SOLICITED; 343 bth2 |= IB_BTH_REQ_ACK; 344 if (++qp->s_cur == qp->s_size) 345 qp->s_cur = 0; 346 break; 347 348 case IB_WR_RDMA_WRITE: 349 if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT)) 350 qp->s_lsn++; 351 goto no_flow_control; 352 case IB_WR_RDMA_WRITE_WITH_IMM: 353 /* If no credit, return. */ 354 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT) && 355 rvt_cmp_msn(wqe->ssn, qp->s_lsn + 1) > 0) { 356 qp->s_flags |= RVT_S_WAIT_SSN_CREDIT; 357 goto bail; 358 } 359 no_flow_control: 360 ohdr->u.rc.reth.vaddr = 361 cpu_to_be64(wqe->rdma_wr.remote_addr); 362 ohdr->u.rc.reth.rkey = 363 cpu_to_be32(wqe->rdma_wr.rkey); 364 ohdr->u.rc.reth.length = cpu_to_be32(len); 365 hwords += sizeof(struct ib_reth) / sizeof(u32); 366 if (len > pmtu) { 367 qp->s_state = OP(RDMA_WRITE_FIRST); 368 len = pmtu; 369 break; 370 } 371 if (wqe->rdma_wr.wr.opcode == IB_WR_RDMA_WRITE) 372 qp->s_state = OP(RDMA_WRITE_ONLY); 373 else { 374 qp->s_state = OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE); 375 /* Immediate data comes after RETH */ 376 ohdr->u.rc.imm_data = 377 wqe->rdma_wr.wr.ex.imm_data; 378 hwords += 1; 379 if (wqe->rdma_wr.wr.send_flags & IB_SEND_SOLICITED) 380 bth0 |= IB_BTH_SOLICITED; 381 } 382 bth2 |= IB_BTH_REQ_ACK; 383 if (++qp->s_cur == qp->s_size) 384 qp->s_cur = 0; 385 break; 386 387 case IB_WR_RDMA_READ: 388 /* 389 * Don't allow more operations to be started 390 * than the QP limits allow. 391 */ 392 if (newreq) { 393 if (qp->s_num_rd_atomic >= 394 qp->s_max_rd_atomic) { 395 qp->s_flags |= RVT_S_WAIT_RDMAR; 396 goto bail; 397 } 398 qp->s_num_rd_atomic++; 399 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT)) 400 qp->s_lsn++; 401 } 402 403 ohdr->u.rc.reth.vaddr = 404 cpu_to_be64(wqe->rdma_wr.remote_addr); 405 ohdr->u.rc.reth.rkey = 406 cpu_to_be32(wqe->rdma_wr.rkey); 407 ohdr->u.rc.reth.length = cpu_to_be32(len); 408 qp->s_state = OP(RDMA_READ_REQUEST); 409 hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32); 410 ss = NULL; 411 len = 0; 412 bth2 |= IB_BTH_REQ_ACK; 413 if (++qp->s_cur == qp->s_size) 414 qp->s_cur = 0; 415 break; 416 417 case IB_WR_ATOMIC_CMP_AND_SWP: 418 case IB_WR_ATOMIC_FETCH_AND_ADD: 419 /* 420 * Don't allow more operations to be started 421 * than the QP limits allow. 422 */ 423 if (newreq) { 424 if (qp->s_num_rd_atomic >= 425 qp->s_max_rd_atomic) { 426 qp->s_flags |= RVT_S_WAIT_RDMAR; 427 goto bail; 428 } 429 qp->s_num_rd_atomic++; 430 if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT)) 431 qp->s_lsn++; 432 } 433 if (wqe->atomic_wr.wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP) { 434 qp->s_state = OP(COMPARE_SWAP); 435 put_ib_ateth_swap(wqe->atomic_wr.swap, 436 &ohdr->u.atomic_eth); 437 put_ib_ateth_swap(wqe->atomic_wr.compare_add, 438 &ohdr->u.atomic_eth); 439 } else { 440 qp->s_state = OP(FETCH_ADD); 441 put_ib_ateth_swap(wqe->atomic_wr.compare_add, 442 &ohdr->u.atomic_eth); 443 put_ib_ateth_swap(0, &ohdr->u.atomic_eth); 444 } 445 put_ib_ateth_vaddr(wqe->atomic_wr.remote_addr, 446 &ohdr->u.atomic_eth); 447 ohdr->u.atomic_eth.rkey = cpu_to_be32( 448 wqe->atomic_wr.rkey); 449 hwords += sizeof(struct ib_atomic_eth) / sizeof(u32); 450 ss = NULL; 451 len = 0; 452 bth2 |= IB_BTH_REQ_ACK; 453 if (++qp->s_cur == qp->s_size) 454 qp->s_cur = 0; 455 break; 456 457 default: 458 goto bail; 459 } 460 qp->s_sge.sge = wqe->sg_list[0]; 461 qp->s_sge.sg_list = wqe->sg_list + 1; 462 qp->s_sge.num_sge = wqe->wr.num_sge; 463 qp->s_sge.total_len = wqe->length; 464 qp->s_len = wqe->length; 465 if (newreq) { 466 qp->s_tail++; 467 if (qp->s_tail >= qp->s_size) 468 qp->s_tail = 0; 469 } 470 if (wqe->wr.opcode == IB_WR_RDMA_READ) 471 qp->s_psn = wqe->lpsn + 1; 472 else 473 qp->s_psn++; 474 break; 475 476 case OP(RDMA_READ_RESPONSE_FIRST): 477 /* 478 * qp->s_state is normally set to the opcode of the 479 * last packet constructed for new requests and therefore 480 * is never set to RDMA read response. 481 * RDMA_READ_RESPONSE_FIRST is used by the ACK processing 482 * thread to indicate a SEND needs to be restarted from an 483 * earlier PSN without interferring with the sending thread. 484 * See qib_restart_rc(). 485 */ 486 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu); 487 /* FALLTHROUGH */ 488 case OP(SEND_FIRST): 489 qp->s_state = OP(SEND_MIDDLE); 490 /* FALLTHROUGH */ 491 case OP(SEND_MIDDLE): 492 bth2 = qp->s_psn++ & QIB_PSN_MASK; 493 ss = &qp->s_sge; 494 len = qp->s_len; 495 if (len > pmtu) { 496 len = pmtu; 497 break; 498 } 499 if (wqe->wr.opcode == IB_WR_SEND) 500 qp->s_state = OP(SEND_LAST); 501 else { 502 qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE); 503 /* Immediate data comes after the BTH */ 504 ohdr->u.imm_data = wqe->wr.ex.imm_data; 505 hwords += 1; 506 } 507 if (wqe->wr.send_flags & IB_SEND_SOLICITED) 508 bth0 |= IB_BTH_SOLICITED; 509 bth2 |= IB_BTH_REQ_ACK; 510 qp->s_cur++; 511 if (qp->s_cur >= qp->s_size) 512 qp->s_cur = 0; 513 break; 514 515 case OP(RDMA_READ_RESPONSE_LAST): 516 /* 517 * qp->s_state is normally set to the opcode of the 518 * last packet constructed for new requests and therefore 519 * is never set to RDMA read response. 520 * RDMA_READ_RESPONSE_LAST is used by the ACK processing 521 * thread to indicate a RDMA write needs to be restarted from 522 * an earlier PSN without interferring with the sending thread. 523 * See qib_restart_rc(). 524 */ 525 qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu); 526 /* FALLTHROUGH */ 527 case OP(RDMA_WRITE_FIRST): 528 qp->s_state = OP(RDMA_WRITE_MIDDLE); 529 /* FALLTHROUGH */ 530 case OP(RDMA_WRITE_MIDDLE): 531 bth2 = qp->s_psn++ & QIB_PSN_MASK; 532 ss = &qp->s_sge; 533 len = qp->s_len; 534 if (len > pmtu) { 535 len = pmtu; 536 break; 537 } 538 if (wqe->wr.opcode == IB_WR_RDMA_WRITE) 539 qp->s_state = OP(RDMA_WRITE_LAST); 540 else { 541 qp->s_state = OP(RDMA_WRITE_LAST_WITH_IMMEDIATE); 542 /* Immediate data comes after the BTH */ 543 ohdr->u.imm_data = wqe->wr.ex.imm_data; 544 hwords += 1; 545 if (wqe->wr.send_flags & IB_SEND_SOLICITED) 546 bth0 |= IB_BTH_SOLICITED; 547 } 548 bth2 |= IB_BTH_REQ_ACK; 549 qp->s_cur++; 550 if (qp->s_cur >= qp->s_size) 551 qp->s_cur = 0; 552 break; 553 554 case OP(RDMA_READ_RESPONSE_MIDDLE): 555 /* 556 * qp->s_state is normally set to the opcode of the 557 * last packet constructed for new requests and therefore 558 * is never set to RDMA read response. 559 * RDMA_READ_RESPONSE_MIDDLE is used by the ACK processing 560 * thread to indicate a RDMA read needs to be restarted from 561 * an earlier PSN without interferring with the sending thread. 562 * See qib_restart_rc(). 563 */ 564 len = ((qp->s_psn - wqe->psn) & QIB_PSN_MASK) * pmtu; 565 ohdr->u.rc.reth.vaddr = 566 cpu_to_be64(wqe->rdma_wr.remote_addr + len); 567 ohdr->u.rc.reth.rkey = 568 cpu_to_be32(wqe->rdma_wr.rkey); 569 ohdr->u.rc.reth.length = cpu_to_be32(wqe->length - len); 570 qp->s_state = OP(RDMA_READ_REQUEST); 571 hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32); 572 bth2 = (qp->s_psn & QIB_PSN_MASK) | IB_BTH_REQ_ACK; 573 qp->s_psn = wqe->lpsn + 1; 574 ss = NULL; 575 len = 0; 576 qp->s_cur++; 577 if (qp->s_cur == qp->s_size) 578 qp->s_cur = 0; 579 break; 580 } 581 qp->s_sending_hpsn = bth2; 582 delta = (((int) bth2 - (int) wqe->psn) << 8) >> 8; 583 if (delta && delta % QIB_PSN_CREDIT == 0) 584 bth2 |= IB_BTH_REQ_ACK; 585 if (qp->s_flags & RVT_S_SEND_ONE) { 586 qp->s_flags &= ~RVT_S_SEND_ONE; 587 qp->s_flags |= RVT_S_WAIT_ACK; 588 bth2 |= IB_BTH_REQ_ACK; 589 } 590 qp->s_len -= len; 591 qp->s_hdrwords = hwords; 592 qp->s_cur_sge = ss; 593 qp->s_cur_size = len; 594 qib_make_ruc_header(qp, ohdr, bth0 | (qp->s_state << 24), bth2); 595 done: 596 return 1; 597 bail: 598 qp->s_flags &= ~RVT_S_BUSY; 599 return ret; 600 } 601 602 /** 603 * qib_send_rc_ack - Construct an ACK packet and send it 604 * @qp: a pointer to the QP 605 * 606 * This is called from qib_rc_rcv() and qib_kreceive(). 607 * Note that RDMA reads and atomics are handled in the 608 * send side QP state and tasklet. 609 */ 610 void qib_send_rc_ack(struct rvt_qp *qp) 611 { 612 struct qib_devdata *dd = dd_from_ibdev(qp->ibqp.device); 613 struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num); 614 struct qib_pportdata *ppd = ppd_from_ibp(ibp); 615 u64 pbc; 616 u16 lrh0; 617 u32 bth0; 618 u32 hwords; 619 u32 pbufn; 620 u32 __iomem *piobuf; 621 struct ib_header hdr; 622 struct ib_other_headers *ohdr; 623 u32 control; 624 unsigned long flags; 625 626 spin_lock_irqsave(&qp->s_lock, flags); 627 628 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) 629 goto unlock; 630 631 /* Don't send ACK or NAK if a RDMA read or atomic is pending. */ 632 if ((qp->s_flags & RVT_S_RESP_PENDING) || qp->s_rdma_ack_cnt) 633 goto queue_ack; 634 635 /* Construct the header with s_lock held so APM doesn't change it. */ 636 ohdr = &hdr.u.oth; 637 lrh0 = QIB_LRH_BTH; 638 /* header size in 32-bit words LRH+BTH+AETH = (8+12+4)/4. */ 639 hwords = 6; 640 if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & 641 IB_AH_GRH)) { 642 hwords += qib_make_grh(ibp, &hdr.u.l.grh, 643 rdma_ah_read_grh(&qp->remote_ah_attr), 644 hwords, 0); 645 ohdr = &hdr.u.l.oth; 646 lrh0 = QIB_LRH_GRH; 647 } 648 /* read pkey_index w/o lock (its atomic) */ 649 bth0 = qib_get_pkey(ibp, qp->s_pkey_index) | (OP(ACKNOWLEDGE) << 24); 650 if (qp->s_mig_state == IB_MIG_MIGRATED) 651 bth0 |= IB_BTH_MIG_REQ; 652 if (qp->r_nak_state) 653 ohdr->u.aeth = cpu_to_be32((qp->r_msn & IB_MSN_MASK) | 654 (qp->r_nak_state << 655 IB_AETH_CREDIT_SHIFT)); 656 else 657 ohdr->u.aeth = rvt_compute_aeth(qp); 658 lrh0 |= ibp->sl_to_vl[rdma_ah_get_sl(&qp->remote_ah_attr)] << 12 | 659 rdma_ah_get_sl(&qp->remote_ah_attr) << 4; 660 hdr.lrh[0] = cpu_to_be16(lrh0); 661 hdr.lrh[1] = cpu_to_be16(rdma_ah_get_dlid(&qp->remote_ah_attr)); 662 hdr.lrh[2] = cpu_to_be16(hwords + SIZE_OF_CRC); 663 hdr.lrh[3] = cpu_to_be16(ppd->lid | 664 rdma_ah_get_path_bits(&qp->remote_ah_attr)); 665 ohdr->bth[0] = cpu_to_be32(bth0); 666 ohdr->bth[1] = cpu_to_be32(qp->remote_qpn); 667 ohdr->bth[2] = cpu_to_be32(qp->r_ack_psn & QIB_PSN_MASK); 668 669 spin_unlock_irqrestore(&qp->s_lock, flags); 670 671 /* Don't try to send ACKs if the link isn't ACTIVE */ 672 if (!(ppd->lflags & QIBL_LINKACTIVE)) 673 goto done; 674 675 control = dd->f_setpbc_control(ppd, hwords + SIZE_OF_CRC, 676 qp->s_srate, lrh0 >> 12); 677 /* length is + 1 for the control dword */ 678 pbc = ((u64) control << 32) | (hwords + 1); 679 680 piobuf = dd->f_getsendbuf(ppd, pbc, &pbufn); 681 if (!piobuf) { 682 /* 683 * We are out of PIO buffers at the moment. 684 * Pass responsibility for sending the ACK to the 685 * send tasklet so that when a PIO buffer becomes 686 * available, the ACK is sent ahead of other outgoing 687 * packets. 688 */ 689 spin_lock_irqsave(&qp->s_lock, flags); 690 goto queue_ack; 691 } 692 693 /* 694 * Write the pbc. 695 * We have to flush after the PBC for correctness 696 * on some cpus or WC buffer can be written out of order. 697 */ 698 writeq(pbc, piobuf); 699 700 if (dd->flags & QIB_PIO_FLUSH_WC) { 701 u32 *hdrp = (u32 *) &hdr; 702 703 qib_flush_wc(); 704 qib_pio_copy(piobuf + 2, hdrp, hwords - 1); 705 qib_flush_wc(); 706 __raw_writel(hdrp[hwords - 1], piobuf + hwords + 1); 707 } else 708 qib_pio_copy(piobuf + 2, (u32 *) &hdr, hwords); 709 710 if (dd->flags & QIB_USE_SPCL_TRIG) { 711 u32 spcl_off = (pbufn >= dd->piobcnt2k) ? 2047 : 1023; 712 713 qib_flush_wc(); 714 __raw_writel(0xaebecede, piobuf + spcl_off); 715 } 716 717 qib_flush_wc(); 718 qib_sendbuf_done(dd, pbufn); 719 720 this_cpu_inc(ibp->pmastats->n_unicast_xmit); 721 goto done; 722 723 queue_ack: 724 if (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK) { 725 this_cpu_inc(*ibp->rvp.rc_qacks); 726 qp->s_flags |= RVT_S_ACK_PENDING | RVT_S_RESP_PENDING; 727 qp->s_nak_state = qp->r_nak_state; 728 qp->s_ack_psn = qp->r_ack_psn; 729 730 /* Schedule the send tasklet. */ 731 qib_schedule_send(qp); 732 } 733 unlock: 734 spin_unlock_irqrestore(&qp->s_lock, flags); 735 done: 736 return; 737 } 738 739 /** 740 * reset_psn - reset the QP state to send starting from PSN 741 * @qp: the QP 742 * @psn: the packet sequence number to restart at 743 * 744 * This is called from qib_rc_rcv() to process an incoming RC ACK 745 * for the given QP. 746 * Called at interrupt level with the QP s_lock held. 747 */ 748 static void reset_psn(struct rvt_qp *qp, u32 psn) 749 { 750 u32 n = qp->s_acked; 751 struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, n); 752 u32 opcode; 753 754 qp->s_cur = n; 755 756 /* 757 * If we are starting the request from the beginning, 758 * let the normal send code handle initialization. 759 */ 760 if (qib_cmp24(psn, wqe->psn) <= 0) { 761 qp->s_state = OP(SEND_LAST); 762 goto done; 763 } 764 765 /* Find the work request opcode corresponding to the given PSN. */ 766 opcode = wqe->wr.opcode; 767 for (;;) { 768 int diff; 769 770 if (++n == qp->s_size) 771 n = 0; 772 if (n == qp->s_tail) 773 break; 774 wqe = rvt_get_swqe_ptr(qp, n); 775 diff = qib_cmp24(psn, wqe->psn); 776 if (diff < 0) 777 break; 778 qp->s_cur = n; 779 /* 780 * If we are starting the request from the beginning, 781 * let the normal send code handle initialization. 782 */ 783 if (diff == 0) { 784 qp->s_state = OP(SEND_LAST); 785 goto done; 786 } 787 opcode = wqe->wr.opcode; 788 } 789 790 /* 791 * Set the state to restart in the middle of a request. 792 * Don't change the s_sge, s_cur_sge, or s_cur_size. 793 * See qib_make_rc_req(). 794 */ 795 switch (opcode) { 796 case IB_WR_SEND: 797 case IB_WR_SEND_WITH_IMM: 798 qp->s_state = OP(RDMA_READ_RESPONSE_FIRST); 799 break; 800 801 case IB_WR_RDMA_WRITE: 802 case IB_WR_RDMA_WRITE_WITH_IMM: 803 qp->s_state = OP(RDMA_READ_RESPONSE_LAST); 804 break; 805 806 case IB_WR_RDMA_READ: 807 qp->s_state = OP(RDMA_READ_RESPONSE_MIDDLE); 808 break; 809 810 default: 811 /* 812 * This case shouldn't happen since its only 813 * one PSN per req. 814 */ 815 qp->s_state = OP(SEND_LAST); 816 } 817 done: 818 qp->s_psn = psn; 819 /* 820 * Set RVT_S_WAIT_PSN as qib_rc_complete() may start the timer 821 * asynchronously before the send tasklet can get scheduled. 822 * Doing it in qib_make_rc_req() is too late. 823 */ 824 if ((qib_cmp24(qp->s_psn, qp->s_sending_hpsn) <= 0) && 825 (qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)) 826 qp->s_flags |= RVT_S_WAIT_PSN; 827 } 828 829 /* 830 * Back up requester to resend the last un-ACKed request. 831 * The QP r_lock and s_lock should be held and interrupts disabled. 832 */ 833 void qib_restart_rc(struct rvt_qp *qp, u32 psn, int wait) 834 { 835 struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, qp->s_acked); 836 struct qib_ibport *ibp; 837 838 if (qp->s_retry == 0) { 839 if (qp->s_mig_state == IB_MIG_ARMED) { 840 qib_migrate_qp(qp); 841 qp->s_retry = qp->s_retry_cnt; 842 } else if (qp->s_last == qp->s_acked) { 843 qib_send_complete(qp, wqe, IB_WC_RETRY_EXC_ERR); 844 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR); 845 return; 846 } else /* XXX need to handle delayed completion */ 847 return; 848 } else 849 qp->s_retry--; 850 851 ibp = to_iport(qp->ibqp.device, qp->port_num); 852 if (wqe->wr.opcode == IB_WR_RDMA_READ) 853 ibp->rvp.n_rc_resends++; 854 else 855 ibp->rvp.n_rc_resends += (qp->s_psn - psn) & QIB_PSN_MASK; 856 857 qp->s_flags &= ~(RVT_S_WAIT_FENCE | RVT_S_WAIT_RDMAR | 858 RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_PSN | 859 RVT_S_WAIT_ACK); 860 if (wait) 861 qp->s_flags |= RVT_S_SEND_ONE; 862 reset_psn(qp, psn); 863 } 864 865 /* 866 * Set qp->s_sending_psn to the next PSN after the given one. 867 * This would be psn+1 except when RDMA reads are present. 868 */ 869 static void reset_sending_psn(struct rvt_qp *qp, u32 psn) 870 { 871 struct rvt_swqe *wqe; 872 u32 n = qp->s_last; 873 874 /* Find the work request corresponding to the given PSN. */ 875 for (;;) { 876 wqe = rvt_get_swqe_ptr(qp, n); 877 if (qib_cmp24(psn, wqe->lpsn) <= 0) { 878 if (wqe->wr.opcode == IB_WR_RDMA_READ) 879 qp->s_sending_psn = wqe->lpsn + 1; 880 else 881 qp->s_sending_psn = psn + 1; 882 break; 883 } 884 if (++n == qp->s_size) 885 n = 0; 886 if (n == qp->s_tail) 887 break; 888 } 889 } 890 891 /* 892 * This should be called with the QP s_lock held and interrupts disabled. 893 */ 894 void qib_rc_send_complete(struct rvt_qp *qp, struct ib_header *hdr) 895 { 896 struct ib_other_headers *ohdr; 897 struct rvt_swqe *wqe; 898 u32 opcode; 899 u32 psn; 900 901 if (!(ib_rvt_state_ops[qp->state] & RVT_SEND_OR_FLUSH_OR_RECV_OK)) 902 return; 903 904 /* Find out where the BTH is */ 905 if ((be16_to_cpu(hdr->lrh[0]) & 3) == QIB_LRH_BTH) 906 ohdr = &hdr->u.oth; 907 else 908 ohdr = &hdr->u.l.oth; 909 910 opcode = be32_to_cpu(ohdr->bth[0]) >> 24; 911 if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) && 912 opcode <= OP(ATOMIC_ACKNOWLEDGE)) { 913 WARN_ON(!qp->s_rdma_ack_cnt); 914 qp->s_rdma_ack_cnt--; 915 return; 916 } 917 918 psn = be32_to_cpu(ohdr->bth[2]); 919 reset_sending_psn(qp, psn); 920 921 /* 922 * Start timer after a packet requesting an ACK has been sent and 923 * there are still requests that haven't been acked. 924 */ 925 if ((psn & IB_BTH_REQ_ACK) && qp->s_acked != qp->s_tail && 926 !(qp->s_flags & (RVT_S_TIMER | RVT_S_WAIT_RNR | RVT_S_WAIT_PSN)) && 927 (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) 928 rvt_add_retry_timer(qp); 929 930 while (qp->s_last != qp->s_acked) { 931 u32 s_last; 932 933 wqe = rvt_get_swqe_ptr(qp, qp->s_last); 934 if (qib_cmp24(wqe->lpsn, qp->s_sending_psn) >= 0 && 935 qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0) 936 break; 937 s_last = qp->s_last; 938 if (++s_last >= qp->s_size) 939 s_last = 0; 940 qp->s_last = s_last; 941 /* see post_send() */ 942 barrier(); 943 rvt_put_swqe(wqe); 944 rvt_qp_swqe_complete(qp, 945 wqe, 946 ib_qib_wc_opcode[wqe->wr.opcode], 947 IB_WC_SUCCESS); 948 } 949 /* 950 * If we were waiting for sends to complete before resending, 951 * and they are now complete, restart sending. 952 */ 953 if (qp->s_flags & RVT_S_WAIT_PSN && 954 qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) > 0) { 955 qp->s_flags &= ~RVT_S_WAIT_PSN; 956 qp->s_sending_psn = qp->s_psn; 957 qp->s_sending_hpsn = qp->s_psn - 1; 958 qib_schedule_send(qp); 959 } 960 } 961 962 static inline void update_last_psn(struct rvt_qp *qp, u32 psn) 963 { 964 qp->s_last_psn = psn; 965 } 966 967 /* 968 * Generate a SWQE completion. 969 * This is similar to qib_send_complete but has to check to be sure 970 * that the SGEs are not being referenced if the SWQE is being resent. 971 */ 972 static struct rvt_swqe *do_rc_completion(struct rvt_qp *qp, 973 struct rvt_swqe *wqe, 974 struct qib_ibport *ibp) 975 { 976 /* 977 * Don't decrement refcount and don't generate a 978 * completion if the SWQE is being resent until the send 979 * is finished. 980 */ 981 if (qib_cmp24(wqe->lpsn, qp->s_sending_psn) < 0 || 982 qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) > 0) { 983 u32 s_last; 984 985 rvt_put_swqe(wqe); 986 s_last = qp->s_last; 987 if (++s_last >= qp->s_size) 988 s_last = 0; 989 qp->s_last = s_last; 990 /* see post_send() */ 991 barrier(); 992 rvt_qp_swqe_complete(qp, 993 wqe, 994 ib_qib_wc_opcode[wqe->wr.opcode], 995 IB_WC_SUCCESS); 996 } else 997 this_cpu_inc(*ibp->rvp.rc_delayed_comp); 998 999 qp->s_retry = qp->s_retry_cnt; 1000 update_last_psn(qp, wqe->lpsn); 1001 1002 /* 1003 * If we are completing a request which is in the process of 1004 * being resent, we can stop resending it since we know the 1005 * responder has already seen it. 1006 */ 1007 if (qp->s_acked == qp->s_cur) { 1008 if (++qp->s_cur >= qp->s_size) 1009 qp->s_cur = 0; 1010 qp->s_acked = qp->s_cur; 1011 wqe = rvt_get_swqe_ptr(qp, qp->s_cur); 1012 if (qp->s_acked != qp->s_tail) { 1013 qp->s_state = OP(SEND_LAST); 1014 qp->s_psn = wqe->psn; 1015 } 1016 } else { 1017 if (++qp->s_acked >= qp->s_size) 1018 qp->s_acked = 0; 1019 if (qp->state == IB_QPS_SQD && qp->s_acked == qp->s_cur) 1020 qp->s_draining = 0; 1021 wqe = rvt_get_swqe_ptr(qp, qp->s_acked); 1022 } 1023 return wqe; 1024 } 1025 1026 /** 1027 * do_rc_ack - process an incoming RC ACK 1028 * @qp: the QP the ACK came in on 1029 * @psn: the packet sequence number of the ACK 1030 * @opcode: the opcode of the request that resulted in the ACK 1031 * 1032 * This is called from qib_rc_rcv_resp() to process an incoming RC ACK 1033 * for the given QP. 1034 * Called at interrupt level with the QP s_lock held. 1035 * Returns 1 if OK, 0 if current operation should be aborted (NAK). 1036 */ 1037 static int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode, 1038 u64 val, struct qib_ctxtdata *rcd) 1039 { 1040 struct qib_ibport *ibp; 1041 enum ib_wc_status status; 1042 struct rvt_swqe *wqe; 1043 int ret = 0; 1044 u32 ack_psn; 1045 int diff; 1046 1047 /* 1048 * Note that NAKs implicitly ACK outstanding SEND and RDMA write 1049 * requests and implicitly NAK RDMA read and atomic requests issued 1050 * before the NAK'ed request. The MSN won't include the NAK'ed 1051 * request but will include an ACK'ed request(s). 1052 */ 1053 ack_psn = psn; 1054 if (aeth >> IB_AETH_NAK_SHIFT) 1055 ack_psn--; 1056 wqe = rvt_get_swqe_ptr(qp, qp->s_acked); 1057 ibp = to_iport(qp->ibqp.device, qp->port_num); 1058 1059 /* 1060 * The MSN might be for a later WQE than the PSN indicates so 1061 * only complete WQEs that the PSN finishes. 1062 */ 1063 while ((diff = qib_cmp24(ack_psn, wqe->lpsn)) >= 0) { 1064 /* 1065 * RDMA_READ_RESPONSE_ONLY is a special case since 1066 * we want to generate completion events for everything 1067 * before the RDMA read, copy the data, then generate 1068 * the completion for the read. 1069 */ 1070 if (wqe->wr.opcode == IB_WR_RDMA_READ && 1071 opcode == OP(RDMA_READ_RESPONSE_ONLY) && 1072 diff == 0) { 1073 ret = 1; 1074 goto bail; 1075 } 1076 /* 1077 * If this request is a RDMA read or atomic, and the ACK is 1078 * for a later operation, this ACK NAKs the RDMA read or 1079 * atomic. In other words, only a RDMA_READ_LAST or ONLY 1080 * can ACK a RDMA read and likewise for atomic ops. Note 1081 * that the NAK case can only happen if relaxed ordering is 1082 * used and requests are sent after an RDMA read or atomic 1083 * is sent but before the response is received. 1084 */ 1085 if ((wqe->wr.opcode == IB_WR_RDMA_READ && 1086 (opcode != OP(RDMA_READ_RESPONSE_LAST) || diff != 0)) || 1087 ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP || 1088 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) && 1089 (opcode != OP(ATOMIC_ACKNOWLEDGE) || diff != 0))) { 1090 /* Retry this request. */ 1091 if (!(qp->r_flags & RVT_R_RDMAR_SEQ)) { 1092 qp->r_flags |= RVT_R_RDMAR_SEQ; 1093 qib_restart_rc(qp, qp->s_last_psn + 1, 0); 1094 if (list_empty(&qp->rspwait)) { 1095 qp->r_flags |= RVT_R_RSP_SEND; 1096 rvt_get_qp(qp); 1097 list_add_tail(&qp->rspwait, 1098 &rcd->qp_wait_list); 1099 } 1100 } 1101 /* 1102 * No need to process the ACK/NAK since we are 1103 * restarting an earlier request. 1104 */ 1105 goto bail; 1106 } 1107 if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP || 1108 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) { 1109 u64 *vaddr = wqe->sg_list[0].vaddr; 1110 *vaddr = val; 1111 } 1112 if (qp->s_num_rd_atomic && 1113 (wqe->wr.opcode == IB_WR_RDMA_READ || 1114 wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP || 1115 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)) { 1116 qp->s_num_rd_atomic--; 1117 /* Restart sending task if fence is complete */ 1118 if ((qp->s_flags & RVT_S_WAIT_FENCE) && 1119 !qp->s_num_rd_atomic) { 1120 qp->s_flags &= ~(RVT_S_WAIT_FENCE | 1121 RVT_S_WAIT_ACK); 1122 qib_schedule_send(qp); 1123 } else if (qp->s_flags & RVT_S_WAIT_RDMAR) { 1124 qp->s_flags &= ~(RVT_S_WAIT_RDMAR | 1125 RVT_S_WAIT_ACK); 1126 qib_schedule_send(qp); 1127 } 1128 } 1129 wqe = do_rc_completion(qp, wqe, ibp); 1130 if (qp->s_acked == qp->s_tail) 1131 break; 1132 } 1133 1134 switch (aeth >> IB_AETH_NAK_SHIFT) { 1135 case 0: /* ACK */ 1136 this_cpu_inc(*ibp->rvp.rc_acks); 1137 if (qp->s_acked != qp->s_tail) { 1138 /* 1139 * We are expecting more ACKs so 1140 * reset the retransmit timer. 1141 */ 1142 rvt_mod_retry_timer(qp); 1143 /* 1144 * We can stop resending the earlier packets and 1145 * continue with the next packet the receiver wants. 1146 */ 1147 if (qib_cmp24(qp->s_psn, psn) <= 0) 1148 reset_psn(qp, psn + 1); 1149 } else { 1150 /* No more acks - kill all timers */ 1151 rvt_stop_rc_timers(qp); 1152 if (qib_cmp24(qp->s_psn, psn) <= 0) { 1153 qp->s_state = OP(SEND_LAST); 1154 qp->s_psn = psn + 1; 1155 } 1156 } 1157 if (qp->s_flags & RVT_S_WAIT_ACK) { 1158 qp->s_flags &= ~RVT_S_WAIT_ACK; 1159 qib_schedule_send(qp); 1160 } 1161 rvt_get_credit(qp, aeth); 1162 qp->s_rnr_retry = qp->s_rnr_retry_cnt; 1163 qp->s_retry = qp->s_retry_cnt; 1164 update_last_psn(qp, psn); 1165 return 1; 1166 1167 case 1: /* RNR NAK */ 1168 ibp->rvp.n_rnr_naks++; 1169 if (qp->s_acked == qp->s_tail) 1170 goto bail; 1171 if (qp->s_flags & RVT_S_WAIT_RNR) 1172 goto bail; 1173 if (qp->s_rnr_retry == 0) { 1174 status = IB_WC_RNR_RETRY_EXC_ERR; 1175 goto class_b; 1176 } 1177 if (qp->s_rnr_retry_cnt < 7) 1178 qp->s_rnr_retry--; 1179 1180 /* The last valid PSN is the previous PSN. */ 1181 update_last_psn(qp, psn - 1); 1182 1183 ibp->rvp.n_rc_resends += (qp->s_psn - psn) & QIB_PSN_MASK; 1184 1185 reset_psn(qp, psn); 1186 1187 qp->s_flags &= ~(RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_ACK); 1188 rvt_stop_rc_timers(qp); 1189 rvt_add_rnr_timer(qp, aeth); 1190 return 0; 1191 1192 case 3: /* NAK */ 1193 if (qp->s_acked == qp->s_tail) 1194 goto bail; 1195 /* The last valid PSN is the previous PSN. */ 1196 update_last_psn(qp, psn - 1); 1197 switch ((aeth >> IB_AETH_CREDIT_SHIFT) & 1198 IB_AETH_CREDIT_MASK) { 1199 case 0: /* PSN sequence error */ 1200 ibp->rvp.n_seq_naks++; 1201 /* 1202 * Back up to the responder's expected PSN. 1203 * Note that we might get a NAK in the middle of an 1204 * RDMA READ response which terminates the RDMA 1205 * READ. 1206 */ 1207 qib_restart_rc(qp, psn, 0); 1208 qib_schedule_send(qp); 1209 break; 1210 1211 case 1: /* Invalid Request */ 1212 status = IB_WC_REM_INV_REQ_ERR; 1213 ibp->rvp.n_other_naks++; 1214 goto class_b; 1215 1216 case 2: /* Remote Access Error */ 1217 status = IB_WC_REM_ACCESS_ERR; 1218 ibp->rvp.n_other_naks++; 1219 goto class_b; 1220 1221 case 3: /* Remote Operation Error */ 1222 status = IB_WC_REM_OP_ERR; 1223 ibp->rvp.n_other_naks++; 1224 class_b: 1225 if (qp->s_last == qp->s_acked) { 1226 qib_send_complete(qp, wqe, status); 1227 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR); 1228 } 1229 break; 1230 1231 default: 1232 /* Ignore other reserved NAK error codes */ 1233 goto reserved; 1234 } 1235 qp->s_retry = qp->s_retry_cnt; 1236 qp->s_rnr_retry = qp->s_rnr_retry_cnt; 1237 goto bail; 1238 1239 default: /* 2: reserved */ 1240 reserved: 1241 /* Ignore reserved NAK codes. */ 1242 goto bail; 1243 } 1244 1245 bail: 1246 rvt_stop_rc_timers(qp); 1247 return ret; 1248 } 1249 1250 /* 1251 * We have seen an out of sequence RDMA read middle or last packet. 1252 * This ACKs SENDs and RDMA writes up to the first RDMA read or atomic SWQE. 1253 */ 1254 static void rdma_seq_err(struct rvt_qp *qp, struct qib_ibport *ibp, u32 psn, 1255 struct qib_ctxtdata *rcd) 1256 { 1257 struct rvt_swqe *wqe; 1258 1259 /* Remove QP from retry timer */ 1260 rvt_stop_rc_timers(qp); 1261 1262 wqe = rvt_get_swqe_ptr(qp, qp->s_acked); 1263 1264 while (qib_cmp24(psn, wqe->lpsn) > 0) { 1265 if (wqe->wr.opcode == IB_WR_RDMA_READ || 1266 wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP || 1267 wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) 1268 break; 1269 wqe = do_rc_completion(qp, wqe, ibp); 1270 } 1271 1272 ibp->rvp.n_rdma_seq++; 1273 qp->r_flags |= RVT_R_RDMAR_SEQ; 1274 qib_restart_rc(qp, qp->s_last_psn + 1, 0); 1275 if (list_empty(&qp->rspwait)) { 1276 qp->r_flags |= RVT_R_RSP_SEND; 1277 rvt_get_qp(qp); 1278 list_add_tail(&qp->rspwait, &rcd->qp_wait_list); 1279 } 1280 } 1281 1282 /** 1283 * qib_rc_rcv_resp - process an incoming RC response packet 1284 * @ibp: the port this packet came in on 1285 * @ohdr: the other headers for this packet 1286 * @data: the packet data 1287 * @tlen: the packet length 1288 * @qp: the QP for this packet 1289 * @opcode: the opcode for this packet 1290 * @psn: the packet sequence number for this packet 1291 * @hdrsize: the header length 1292 * @pmtu: the path MTU 1293 * 1294 * This is called from qib_rc_rcv() to process an incoming RC response 1295 * packet for the given QP. 1296 * Called at interrupt level. 1297 */ 1298 static void qib_rc_rcv_resp(struct qib_ibport *ibp, 1299 struct ib_other_headers *ohdr, 1300 void *data, u32 tlen, 1301 struct rvt_qp *qp, 1302 u32 opcode, 1303 u32 psn, u32 hdrsize, u32 pmtu, 1304 struct qib_ctxtdata *rcd) 1305 { 1306 struct rvt_swqe *wqe; 1307 struct qib_pportdata *ppd = ppd_from_ibp(ibp); 1308 enum ib_wc_status status; 1309 unsigned long flags; 1310 int diff; 1311 u32 pad; 1312 u32 aeth; 1313 u64 val; 1314 1315 if (opcode != OP(RDMA_READ_RESPONSE_MIDDLE)) { 1316 /* 1317 * If ACK'd PSN on SDMA busy list try to make progress to 1318 * reclaim SDMA credits. 1319 */ 1320 if ((qib_cmp24(psn, qp->s_sending_psn) >= 0) && 1321 (qib_cmp24(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)) { 1322 1323 /* 1324 * If send tasklet not running attempt to progress 1325 * SDMA queue. 1326 */ 1327 if (!(qp->s_flags & RVT_S_BUSY)) { 1328 /* Acquire SDMA Lock */ 1329 spin_lock_irqsave(&ppd->sdma_lock, flags); 1330 /* Invoke sdma make progress */ 1331 qib_sdma_make_progress(ppd); 1332 /* Release SDMA Lock */ 1333 spin_unlock_irqrestore(&ppd->sdma_lock, flags); 1334 } 1335 } 1336 } 1337 1338 spin_lock_irqsave(&qp->s_lock, flags); 1339 if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) 1340 goto ack_done; 1341 1342 /* Ignore invalid responses. */ 1343 smp_read_barrier_depends(); /* see post_one_send */ 1344 if (qib_cmp24(psn, READ_ONCE(qp->s_next_psn)) >= 0) 1345 goto ack_done; 1346 1347 /* Ignore duplicate responses. */ 1348 diff = qib_cmp24(psn, qp->s_last_psn); 1349 if (unlikely(diff <= 0)) { 1350 /* Update credits for "ghost" ACKs */ 1351 if (diff == 0 && opcode == OP(ACKNOWLEDGE)) { 1352 aeth = be32_to_cpu(ohdr->u.aeth); 1353 if ((aeth >> IB_AETH_NAK_SHIFT) == 0) 1354 rvt_get_credit(qp, aeth); 1355 } 1356 goto ack_done; 1357 } 1358 1359 /* 1360 * Skip everything other than the PSN we expect, if we are waiting 1361 * for a reply to a restarted RDMA read or atomic op. 1362 */ 1363 if (qp->r_flags & RVT_R_RDMAR_SEQ) { 1364 if (qib_cmp24(psn, qp->s_last_psn + 1) != 0) 1365 goto ack_done; 1366 qp->r_flags &= ~RVT_R_RDMAR_SEQ; 1367 } 1368 1369 if (unlikely(qp->s_acked == qp->s_tail)) 1370 goto ack_done; 1371 wqe = rvt_get_swqe_ptr(qp, qp->s_acked); 1372 status = IB_WC_SUCCESS; 1373 1374 switch (opcode) { 1375 case OP(ACKNOWLEDGE): 1376 case OP(ATOMIC_ACKNOWLEDGE): 1377 case OP(RDMA_READ_RESPONSE_FIRST): 1378 aeth = be32_to_cpu(ohdr->u.aeth); 1379 if (opcode == OP(ATOMIC_ACKNOWLEDGE)) 1380 val = ib_u64_get(&ohdr->u.at.atomic_ack_eth); 1381 else 1382 val = 0; 1383 if (!do_rc_ack(qp, aeth, psn, opcode, val, rcd) || 1384 opcode != OP(RDMA_READ_RESPONSE_FIRST)) 1385 goto ack_done; 1386 hdrsize += 4; 1387 wqe = rvt_get_swqe_ptr(qp, qp->s_acked); 1388 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ)) 1389 goto ack_op_err; 1390 /* 1391 * If this is a response to a resent RDMA read, we 1392 * have to be careful to copy the data to the right 1393 * location. 1394 */ 1395 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge, 1396 wqe, psn, pmtu); 1397 goto read_middle; 1398 1399 case OP(RDMA_READ_RESPONSE_MIDDLE): 1400 /* no AETH, no ACK */ 1401 if (unlikely(qib_cmp24(psn, qp->s_last_psn + 1))) 1402 goto ack_seq_err; 1403 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ)) 1404 goto ack_op_err; 1405 read_middle: 1406 if (unlikely(tlen != (hdrsize + pmtu + 4))) 1407 goto ack_len_err; 1408 if (unlikely(pmtu >= qp->s_rdma_read_len)) 1409 goto ack_len_err; 1410 1411 /* 1412 * We got a response so update the timeout. 1413 * 4.096 usec. * (1 << qp->timeout) 1414 */ 1415 rvt_mod_retry_timer(qp); 1416 if (qp->s_flags & RVT_S_WAIT_ACK) { 1417 qp->s_flags &= ~RVT_S_WAIT_ACK; 1418 qib_schedule_send(qp); 1419 } 1420 1421 if (opcode == OP(RDMA_READ_RESPONSE_MIDDLE)) 1422 qp->s_retry = qp->s_retry_cnt; 1423 1424 /* 1425 * Update the RDMA receive state but do the copy w/o 1426 * holding the locks and blocking interrupts. 1427 */ 1428 qp->s_rdma_read_len -= pmtu; 1429 update_last_psn(qp, psn); 1430 spin_unlock_irqrestore(&qp->s_lock, flags); 1431 qib_copy_sge(&qp->s_rdma_read_sge, data, pmtu, 0); 1432 goto bail; 1433 1434 case OP(RDMA_READ_RESPONSE_ONLY): 1435 aeth = be32_to_cpu(ohdr->u.aeth); 1436 if (!do_rc_ack(qp, aeth, psn, opcode, 0, rcd)) 1437 goto ack_done; 1438 /* Get the number of bytes the message was padded by. */ 1439 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3; 1440 /* 1441 * Check that the data size is >= 0 && <= pmtu. 1442 * Remember to account for the AETH header (4) and 1443 * ICRC (4). 1444 */ 1445 if (unlikely(tlen < (hdrsize + pad + 8))) 1446 goto ack_len_err; 1447 /* 1448 * If this is a response to a resent RDMA read, we 1449 * have to be careful to copy the data to the right 1450 * location. 1451 */ 1452 wqe = rvt_get_swqe_ptr(qp, qp->s_acked); 1453 qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge, 1454 wqe, psn, pmtu); 1455 goto read_last; 1456 1457 case OP(RDMA_READ_RESPONSE_LAST): 1458 /* ACKs READ req. */ 1459 if (unlikely(qib_cmp24(psn, qp->s_last_psn + 1))) 1460 goto ack_seq_err; 1461 if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ)) 1462 goto ack_op_err; 1463 /* Get the number of bytes the message was padded by. */ 1464 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3; 1465 /* 1466 * Check that the data size is >= 1 && <= pmtu. 1467 * Remember to account for the AETH header (4) and 1468 * ICRC (4). 1469 */ 1470 if (unlikely(tlen <= (hdrsize + pad + 8))) 1471 goto ack_len_err; 1472 read_last: 1473 tlen -= hdrsize + pad + 8; 1474 if (unlikely(tlen != qp->s_rdma_read_len)) 1475 goto ack_len_err; 1476 aeth = be32_to_cpu(ohdr->u.aeth); 1477 qib_copy_sge(&qp->s_rdma_read_sge, data, tlen, 0); 1478 WARN_ON(qp->s_rdma_read_sge.num_sge); 1479 (void) do_rc_ack(qp, aeth, psn, 1480 OP(RDMA_READ_RESPONSE_LAST), 0, rcd); 1481 goto ack_done; 1482 } 1483 1484 ack_op_err: 1485 status = IB_WC_LOC_QP_OP_ERR; 1486 goto ack_err; 1487 1488 ack_seq_err: 1489 rdma_seq_err(qp, ibp, psn, rcd); 1490 goto ack_done; 1491 1492 ack_len_err: 1493 status = IB_WC_LOC_LEN_ERR; 1494 ack_err: 1495 if (qp->s_last == qp->s_acked) { 1496 qib_send_complete(qp, wqe, status); 1497 rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR); 1498 } 1499 ack_done: 1500 spin_unlock_irqrestore(&qp->s_lock, flags); 1501 bail: 1502 return; 1503 } 1504 1505 /** 1506 * qib_rc_rcv_error - process an incoming duplicate or error RC packet 1507 * @ohdr: the other headers for this packet 1508 * @data: the packet data 1509 * @qp: the QP for this packet 1510 * @opcode: the opcode for this packet 1511 * @psn: the packet sequence number for this packet 1512 * @diff: the difference between the PSN and the expected PSN 1513 * 1514 * This is called from qib_rc_rcv() to process an unexpected 1515 * incoming RC packet for the given QP. 1516 * Called at interrupt level. 1517 * Return 1 if no more processing is needed; otherwise return 0 to 1518 * schedule a response to be sent. 1519 */ 1520 static int qib_rc_rcv_error(struct ib_other_headers *ohdr, 1521 void *data, 1522 struct rvt_qp *qp, 1523 u32 opcode, 1524 u32 psn, 1525 int diff, 1526 struct qib_ctxtdata *rcd) 1527 { 1528 struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num); 1529 struct rvt_ack_entry *e; 1530 unsigned long flags; 1531 u8 i, prev; 1532 int old_req; 1533 1534 if (diff > 0) { 1535 /* 1536 * Packet sequence error. 1537 * A NAK will ACK earlier sends and RDMA writes. 1538 * Don't queue the NAK if we already sent one. 1539 */ 1540 if (!qp->r_nak_state) { 1541 ibp->rvp.n_rc_seqnak++; 1542 qp->r_nak_state = IB_NAK_PSN_ERROR; 1543 /* Use the expected PSN. */ 1544 qp->r_ack_psn = qp->r_psn; 1545 /* 1546 * Wait to send the sequence NAK until all packets 1547 * in the receive queue have been processed. 1548 * Otherwise, we end up propagating congestion. 1549 */ 1550 if (list_empty(&qp->rspwait)) { 1551 qp->r_flags |= RVT_R_RSP_NAK; 1552 rvt_get_qp(qp); 1553 list_add_tail(&qp->rspwait, &rcd->qp_wait_list); 1554 } 1555 } 1556 goto done; 1557 } 1558 1559 /* 1560 * Handle a duplicate request. Don't re-execute SEND, RDMA 1561 * write or atomic op. Don't NAK errors, just silently drop 1562 * the duplicate request. Note that r_sge, r_len, and 1563 * r_rcv_len may be in use so don't modify them. 1564 * 1565 * We are supposed to ACK the earliest duplicate PSN but we 1566 * can coalesce an outstanding duplicate ACK. We have to 1567 * send the earliest so that RDMA reads can be restarted at 1568 * the requester's expected PSN. 1569 * 1570 * First, find where this duplicate PSN falls within the 1571 * ACKs previously sent. 1572 * old_req is true if there is an older response that is scheduled 1573 * to be sent before sending this one. 1574 */ 1575 e = NULL; 1576 old_req = 1; 1577 ibp->rvp.n_rc_dupreq++; 1578 1579 spin_lock_irqsave(&qp->s_lock, flags); 1580 1581 for (i = qp->r_head_ack_queue; ; i = prev) { 1582 if (i == qp->s_tail_ack_queue) 1583 old_req = 0; 1584 if (i) 1585 prev = i - 1; 1586 else 1587 prev = QIB_MAX_RDMA_ATOMIC; 1588 if (prev == qp->r_head_ack_queue) { 1589 e = NULL; 1590 break; 1591 } 1592 e = &qp->s_ack_queue[prev]; 1593 if (!e->opcode) { 1594 e = NULL; 1595 break; 1596 } 1597 if (qib_cmp24(psn, e->psn) >= 0) { 1598 if (prev == qp->s_tail_ack_queue && 1599 qib_cmp24(psn, e->lpsn) <= 0) 1600 old_req = 0; 1601 break; 1602 } 1603 } 1604 switch (opcode) { 1605 case OP(RDMA_READ_REQUEST): { 1606 struct ib_reth *reth; 1607 u32 offset; 1608 u32 len; 1609 1610 /* 1611 * If we didn't find the RDMA read request in the ack queue, 1612 * we can ignore this request. 1613 */ 1614 if (!e || e->opcode != OP(RDMA_READ_REQUEST)) 1615 goto unlock_done; 1616 /* RETH comes after BTH */ 1617 reth = &ohdr->u.rc.reth; 1618 /* 1619 * Address range must be a subset of the original 1620 * request and start on pmtu boundaries. 1621 * We reuse the old ack_queue slot since the requester 1622 * should not back up and request an earlier PSN for the 1623 * same request. 1624 */ 1625 offset = ((psn - e->psn) & QIB_PSN_MASK) * 1626 qp->pmtu; 1627 len = be32_to_cpu(reth->length); 1628 if (unlikely(offset + len != e->rdma_sge.sge_length)) 1629 goto unlock_done; 1630 if (e->rdma_sge.mr) { 1631 rvt_put_mr(e->rdma_sge.mr); 1632 e->rdma_sge.mr = NULL; 1633 } 1634 if (len != 0) { 1635 u32 rkey = be32_to_cpu(reth->rkey); 1636 u64 vaddr = be64_to_cpu(reth->vaddr); 1637 int ok; 1638 1639 ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr, rkey, 1640 IB_ACCESS_REMOTE_READ); 1641 if (unlikely(!ok)) 1642 goto unlock_done; 1643 } else { 1644 e->rdma_sge.vaddr = NULL; 1645 e->rdma_sge.length = 0; 1646 e->rdma_sge.sge_length = 0; 1647 } 1648 e->psn = psn; 1649 if (old_req) 1650 goto unlock_done; 1651 qp->s_tail_ack_queue = prev; 1652 break; 1653 } 1654 1655 case OP(COMPARE_SWAP): 1656 case OP(FETCH_ADD): { 1657 /* 1658 * If we didn't find the atomic request in the ack queue 1659 * or the send tasklet is already backed up to send an 1660 * earlier entry, we can ignore this request. 1661 */ 1662 if (!e || e->opcode != (u8) opcode || old_req) 1663 goto unlock_done; 1664 qp->s_tail_ack_queue = prev; 1665 break; 1666 } 1667 1668 default: 1669 /* 1670 * Ignore this operation if it doesn't request an ACK 1671 * or an earlier RDMA read or atomic is going to be resent. 1672 */ 1673 if (!(psn & IB_BTH_REQ_ACK) || old_req) 1674 goto unlock_done; 1675 /* 1676 * Resend the most recent ACK if this request is 1677 * after all the previous RDMA reads and atomics. 1678 */ 1679 if (i == qp->r_head_ack_queue) { 1680 spin_unlock_irqrestore(&qp->s_lock, flags); 1681 qp->r_nak_state = 0; 1682 qp->r_ack_psn = qp->r_psn - 1; 1683 goto send_ack; 1684 } 1685 /* 1686 * Try to send a simple ACK to work around a Mellanox bug 1687 * which doesn't accept a RDMA read response or atomic 1688 * response as an ACK for earlier SENDs or RDMA writes. 1689 */ 1690 if (!(qp->s_flags & RVT_S_RESP_PENDING)) { 1691 spin_unlock_irqrestore(&qp->s_lock, flags); 1692 qp->r_nak_state = 0; 1693 qp->r_ack_psn = qp->s_ack_queue[i].psn - 1; 1694 goto send_ack; 1695 } 1696 /* 1697 * Resend the RDMA read or atomic op which 1698 * ACKs this duplicate request. 1699 */ 1700 qp->s_tail_ack_queue = i; 1701 break; 1702 } 1703 qp->s_ack_state = OP(ACKNOWLEDGE); 1704 qp->s_flags |= RVT_S_RESP_PENDING; 1705 qp->r_nak_state = 0; 1706 qib_schedule_send(qp); 1707 1708 unlock_done: 1709 spin_unlock_irqrestore(&qp->s_lock, flags); 1710 done: 1711 return 1; 1712 1713 send_ack: 1714 return 0; 1715 } 1716 1717 static inline void qib_update_ack_queue(struct rvt_qp *qp, unsigned n) 1718 { 1719 unsigned next; 1720 1721 next = n + 1; 1722 if (next > QIB_MAX_RDMA_ATOMIC) 1723 next = 0; 1724 qp->s_tail_ack_queue = next; 1725 qp->s_ack_state = OP(ACKNOWLEDGE); 1726 } 1727 1728 /** 1729 * qib_rc_rcv - process an incoming RC packet 1730 * @rcd: the context pointer 1731 * @hdr: the header of this packet 1732 * @has_grh: true if the header has a GRH 1733 * @data: the packet data 1734 * @tlen: the packet length 1735 * @qp: the QP for this packet 1736 * 1737 * This is called from qib_qp_rcv() to process an incoming RC packet 1738 * for the given QP. 1739 * Called at interrupt level. 1740 */ 1741 void qib_rc_rcv(struct qib_ctxtdata *rcd, struct ib_header *hdr, 1742 int has_grh, void *data, u32 tlen, struct rvt_qp *qp) 1743 { 1744 struct qib_ibport *ibp = &rcd->ppd->ibport_data; 1745 struct ib_other_headers *ohdr; 1746 u32 opcode; 1747 u32 hdrsize; 1748 u32 psn; 1749 u32 pad; 1750 struct ib_wc wc; 1751 u32 pmtu = qp->pmtu; 1752 int diff; 1753 struct ib_reth *reth; 1754 unsigned long flags; 1755 int ret; 1756 1757 /* Check for GRH */ 1758 if (!has_grh) { 1759 ohdr = &hdr->u.oth; 1760 hdrsize = 8 + 12; /* LRH + BTH */ 1761 } else { 1762 ohdr = &hdr->u.l.oth; 1763 hdrsize = 8 + 40 + 12; /* LRH + GRH + BTH */ 1764 } 1765 1766 opcode = be32_to_cpu(ohdr->bth[0]); 1767 if (qib_ruc_check_hdr(ibp, hdr, has_grh, qp, opcode)) 1768 return; 1769 1770 psn = be32_to_cpu(ohdr->bth[2]); 1771 opcode >>= 24; 1772 1773 /* 1774 * Process responses (ACKs) before anything else. Note that the 1775 * packet sequence number will be for something in the send work 1776 * queue rather than the expected receive packet sequence number. 1777 * In other words, this QP is the requester. 1778 */ 1779 if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) && 1780 opcode <= OP(ATOMIC_ACKNOWLEDGE)) { 1781 qib_rc_rcv_resp(ibp, ohdr, data, tlen, qp, opcode, psn, 1782 hdrsize, pmtu, rcd); 1783 return; 1784 } 1785 1786 /* Compute 24 bits worth of difference. */ 1787 diff = qib_cmp24(psn, qp->r_psn); 1788 if (unlikely(diff)) { 1789 if (qib_rc_rcv_error(ohdr, data, qp, opcode, psn, diff, rcd)) 1790 return; 1791 goto send_ack; 1792 } 1793 1794 /* Check for opcode sequence errors. */ 1795 switch (qp->r_state) { 1796 case OP(SEND_FIRST): 1797 case OP(SEND_MIDDLE): 1798 if (opcode == OP(SEND_MIDDLE) || 1799 opcode == OP(SEND_LAST) || 1800 opcode == OP(SEND_LAST_WITH_IMMEDIATE)) 1801 break; 1802 goto nack_inv; 1803 1804 case OP(RDMA_WRITE_FIRST): 1805 case OP(RDMA_WRITE_MIDDLE): 1806 if (opcode == OP(RDMA_WRITE_MIDDLE) || 1807 opcode == OP(RDMA_WRITE_LAST) || 1808 opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE)) 1809 break; 1810 goto nack_inv; 1811 1812 default: 1813 if (opcode == OP(SEND_MIDDLE) || 1814 opcode == OP(SEND_LAST) || 1815 opcode == OP(SEND_LAST_WITH_IMMEDIATE) || 1816 opcode == OP(RDMA_WRITE_MIDDLE) || 1817 opcode == OP(RDMA_WRITE_LAST) || 1818 opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE)) 1819 goto nack_inv; 1820 /* 1821 * Note that it is up to the requester to not send a new 1822 * RDMA read or atomic operation before receiving an ACK 1823 * for the previous operation. 1824 */ 1825 break; 1826 } 1827 1828 if (qp->state == IB_QPS_RTR && !(qp->r_flags & RVT_R_COMM_EST)) 1829 rvt_comm_est(qp); 1830 1831 /* OK, process the packet. */ 1832 switch (opcode) { 1833 case OP(SEND_FIRST): 1834 ret = qib_get_rwqe(qp, 0); 1835 if (ret < 0) 1836 goto nack_op_err; 1837 if (!ret) 1838 goto rnr_nak; 1839 qp->r_rcv_len = 0; 1840 /* FALLTHROUGH */ 1841 case OP(SEND_MIDDLE): 1842 case OP(RDMA_WRITE_MIDDLE): 1843 send_middle: 1844 /* Check for invalid length PMTU or posted rwqe len. */ 1845 if (unlikely(tlen != (hdrsize + pmtu + 4))) 1846 goto nack_inv; 1847 qp->r_rcv_len += pmtu; 1848 if (unlikely(qp->r_rcv_len > qp->r_len)) 1849 goto nack_inv; 1850 qib_copy_sge(&qp->r_sge, data, pmtu, 1); 1851 break; 1852 1853 case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE): 1854 /* consume RWQE */ 1855 ret = qib_get_rwqe(qp, 1); 1856 if (ret < 0) 1857 goto nack_op_err; 1858 if (!ret) 1859 goto rnr_nak; 1860 goto send_last_imm; 1861 1862 case OP(SEND_ONLY): 1863 case OP(SEND_ONLY_WITH_IMMEDIATE): 1864 ret = qib_get_rwqe(qp, 0); 1865 if (ret < 0) 1866 goto nack_op_err; 1867 if (!ret) 1868 goto rnr_nak; 1869 qp->r_rcv_len = 0; 1870 if (opcode == OP(SEND_ONLY)) 1871 goto no_immediate_data; 1872 /* fall through -- for SEND_ONLY_WITH_IMMEDIATE */ 1873 case OP(SEND_LAST_WITH_IMMEDIATE): 1874 send_last_imm: 1875 wc.ex.imm_data = ohdr->u.imm_data; 1876 hdrsize += 4; 1877 wc.wc_flags = IB_WC_WITH_IMM; 1878 goto send_last; 1879 case OP(SEND_LAST): 1880 case OP(RDMA_WRITE_LAST): 1881 no_immediate_data: 1882 wc.wc_flags = 0; 1883 wc.ex.imm_data = 0; 1884 send_last: 1885 /* Get the number of bytes the message was padded by. */ 1886 pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3; 1887 /* Check for invalid length. */ 1888 /* XXX LAST len should be >= 1 */ 1889 if (unlikely(tlen < (hdrsize + pad + 4))) 1890 goto nack_inv; 1891 /* Don't count the CRC. */ 1892 tlen -= (hdrsize + pad + 4); 1893 wc.byte_len = tlen + qp->r_rcv_len; 1894 if (unlikely(wc.byte_len > qp->r_len)) 1895 goto nack_inv; 1896 qib_copy_sge(&qp->r_sge, data, tlen, 1); 1897 rvt_put_ss(&qp->r_sge); 1898 qp->r_msn++; 1899 if (!test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags)) 1900 break; 1901 wc.wr_id = qp->r_wr_id; 1902 wc.status = IB_WC_SUCCESS; 1903 if (opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE) || 1904 opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE)) 1905 wc.opcode = IB_WC_RECV_RDMA_WITH_IMM; 1906 else 1907 wc.opcode = IB_WC_RECV; 1908 wc.qp = &qp->ibqp; 1909 wc.src_qp = qp->remote_qpn; 1910 wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr); 1911 wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr); 1912 /* zero fields that are N/A */ 1913 wc.vendor_err = 0; 1914 wc.pkey_index = 0; 1915 wc.dlid_path_bits = 0; 1916 wc.port_num = 0; 1917 /* Signal completion event if the solicited bit is set. */ 1918 rvt_cq_enter(ibcq_to_rvtcq(qp->ibqp.recv_cq), &wc, 1919 (ohdr->bth[0] & 1920 cpu_to_be32(IB_BTH_SOLICITED)) != 0); 1921 break; 1922 1923 case OP(RDMA_WRITE_FIRST): 1924 case OP(RDMA_WRITE_ONLY): 1925 case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE): 1926 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE))) 1927 goto nack_inv; 1928 /* consume RWQE */ 1929 reth = &ohdr->u.rc.reth; 1930 hdrsize += sizeof(*reth); 1931 qp->r_len = be32_to_cpu(reth->length); 1932 qp->r_rcv_len = 0; 1933 qp->r_sge.sg_list = NULL; 1934 if (qp->r_len != 0) { 1935 u32 rkey = be32_to_cpu(reth->rkey); 1936 u64 vaddr = be64_to_cpu(reth->vaddr); 1937 int ok; 1938 1939 /* Check rkey & NAK */ 1940 ok = rvt_rkey_ok(qp, &qp->r_sge.sge, qp->r_len, vaddr, 1941 rkey, IB_ACCESS_REMOTE_WRITE); 1942 if (unlikely(!ok)) 1943 goto nack_acc; 1944 qp->r_sge.num_sge = 1; 1945 } else { 1946 qp->r_sge.num_sge = 0; 1947 qp->r_sge.sge.mr = NULL; 1948 qp->r_sge.sge.vaddr = NULL; 1949 qp->r_sge.sge.length = 0; 1950 qp->r_sge.sge.sge_length = 0; 1951 } 1952 if (opcode == OP(RDMA_WRITE_FIRST)) 1953 goto send_middle; 1954 else if (opcode == OP(RDMA_WRITE_ONLY)) 1955 goto no_immediate_data; 1956 ret = qib_get_rwqe(qp, 1); 1957 if (ret < 0) 1958 goto nack_op_err; 1959 if (!ret) { 1960 rvt_put_ss(&qp->r_sge); 1961 goto rnr_nak; 1962 } 1963 wc.ex.imm_data = ohdr->u.rc.imm_data; 1964 hdrsize += 4; 1965 wc.wc_flags = IB_WC_WITH_IMM; 1966 goto send_last; 1967 1968 case OP(RDMA_READ_REQUEST): { 1969 struct rvt_ack_entry *e; 1970 u32 len; 1971 u8 next; 1972 1973 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ))) 1974 goto nack_inv; 1975 next = qp->r_head_ack_queue + 1; 1976 /* s_ack_queue is size QIB_MAX_RDMA_ATOMIC+1 so use > not >= */ 1977 if (next > QIB_MAX_RDMA_ATOMIC) 1978 next = 0; 1979 spin_lock_irqsave(&qp->s_lock, flags); 1980 if (unlikely(next == qp->s_tail_ack_queue)) { 1981 if (!qp->s_ack_queue[next].sent) 1982 goto nack_inv_unlck; 1983 qib_update_ack_queue(qp, next); 1984 } 1985 e = &qp->s_ack_queue[qp->r_head_ack_queue]; 1986 if (e->opcode == OP(RDMA_READ_REQUEST) && e->rdma_sge.mr) { 1987 rvt_put_mr(e->rdma_sge.mr); 1988 e->rdma_sge.mr = NULL; 1989 } 1990 reth = &ohdr->u.rc.reth; 1991 len = be32_to_cpu(reth->length); 1992 if (len) { 1993 u32 rkey = be32_to_cpu(reth->rkey); 1994 u64 vaddr = be64_to_cpu(reth->vaddr); 1995 int ok; 1996 1997 /* Check rkey & NAK */ 1998 ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr, 1999 rkey, IB_ACCESS_REMOTE_READ); 2000 if (unlikely(!ok)) 2001 goto nack_acc_unlck; 2002 /* 2003 * Update the next expected PSN. We add 1 later 2004 * below, so only add the remainder here. 2005 */ 2006 qp->r_psn += rvt_div_mtu(qp, len - 1); 2007 } else { 2008 e->rdma_sge.mr = NULL; 2009 e->rdma_sge.vaddr = NULL; 2010 e->rdma_sge.length = 0; 2011 e->rdma_sge.sge_length = 0; 2012 } 2013 e->opcode = opcode; 2014 e->sent = 0; 2015 e->psn = psn; 2016 e->lpsn = qp->r_psn; 2017 /* 2018 * We need to increment the MSN here instead of when we 2019 * finish sending the result since a duplicate request would 2020 * increment it more than once. 2021 */ 2022 qp->r_msn++; 2023 qp->r_psn++; 2024 qp->r_state = opcode; 2025 qp->r_nak_state = 0; 2026 qp->r_head_ack_queue = next; 2027 2028 /* Schedule the send tasklet. */ 2029 qp->s_flags |= RVT_S_RESP_PENDING; 2030 qib_schedule_send(qp); 2031 2032 goto sunlock; 2033 } 2034 2035 case OP(COMPARE_SWAP): 2036 case OP(FETCH_ADD): { 2037 struct ib_atomic_eth *ateth; 2038 struct rvt_ack_entry *e; 2039 u64 vaddr; 2040 atomic64_t *maddr; 2041 u64 sdata; 2042 u32 rkey; 2043 u8 next; 2044 2045 if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC))) 2046 goto nack_inv; 2047 next = qp->r_head_ack_queue + 1; 2048 if (next > QIB_MAX_RDMA_ATOMIC) 2049 next = 0; 2050 spin_lock_irqsave(&qp->s_lock, flags); 2051 if (unlikely(next == qp->s_tail_ack_queue)) { 2052 if (!qp->s_ack_queue[next].sent) 2053 goto nack_inv_unlck; 2054 qib_update_ack_queue(qp, next); 2055 } 2056 e = &qp->s_ack_queue[qp->r_head_ack_queue]; 2057 if (e->opcode == OP(RDMA_READ_REQUEST) && e->rdma_sge.mr) { 2058 rvt_put_mr(e->rdma_sge.mr); 2059 e->rdma_sge.mr = NULL; 2060 } 2061 ateth = &ohdr->u.atomic_eth; 2062 vaddr = get_ib_ateth_vaddr(ateth); 2063 if (unlikely(vaddr & (sizeof(u64) - 1))) 2064 goto nack_inv_unlck; 2065 rkey = be32_to_cpu(ateth->rkey); 2066 /* Check rkey & NAK */ 2067 if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64), 2068 vaddr, rkey, 2069 IB_ACCESS_REMOTE_ATOMIC))) 2070 goto nack_acc_unlck; 2071 /* Perform atomic OP and save result. */ 2072 maddr = (atomic64_t *) qp->r_sge.sge.vaddr; 2073 sdata = get_ib_ateth_swap(ateth); 2074 e->atomic_data = (opcode == OP(FETCH_ADD)) ? 2075 (u64) atomic64_add_return(sdata, maddr) - sdata : 2076 (u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr, 2077 get_ib_ateth_compare(ateth), 2078 sdata); 2079 rvt_put_mr(qp->r_sge.sge.mr); 2080 qp->r_sge.num_sge = 0; 2081 e->opcode = opcode; 2082 e->sent = 0; 2083 e->psn = psn; 2084 e->lpsn = psn; 2085 qp->r_msn++; 2086 qp->r_psn++; 2087 qp->r_state = opcode; 2088 qp->r_nak_state = 0; 2089 qp->r_head_ack_queue = next; 2090 2091 /* Schedule the send tasklet. */ 2092 qp->s_flags |= RVT_S_RESP_PENDING; 2093 qib_schedule_send(qp); 2094 2095 goto sunlock; 2096 } 2097 2098 default: 2099 /* NAK unknown opcodes. */ 2100 goto nack_inv; 2101 } 2102 qp->r_psn++; 2103 qp->r_state = opcode; 2104 qp->r_ack_psn = psn; 2105 qp->r_nak_state = 0; 2106 /* Send an ACK if requested or required. */ 2107 if (psn & (1 << 31)) 2108 goto send_ack; 2109 return; 2110 2111 rnr_nak: 2112 qp->r_nak_state = IB_RNR_NAK | qp->r_min_rnr_timer; 2113 qp->r_ack_psn = qp->r_psn; 2114 /* Queue RNR NAK for later */ 2115 if (list_empty(&qp->rspwait)) { 2116 qp->r_flags |= RVT_R_RSP_NAK; 2117 rvt_get_qp(qp); 2118 list_add_tail(&qp->rspwait, &rcd->qp_wait_list); 2119 } 2120 return; 2121 2122 nack_op_err: 2123 rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR); 2124 qp->r_nak_state = IB_NAK_REMOTE_OPERATIONAL_ERROR; 2125 qp->r_ack_psn = qp->r_psn; 2126 /* Queue NAK for later */ 2127 if (list_empty(&qp->rspwait)) { 2128 qp->r_flags |= RVT_R_RSP_NAK; 2129 rvt_get_qp(qp); 2130 list_add_tail(&qp->rspwait, &rcd->qp_wait_list); 2131 } 2132 return; 2133 2134 nack_inv_unlck: 2135 spin_unlock_irqrestore(&qp->s_lock, flags); 2136 nack_inv: 2137 rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR); 2138 qp->r_nak_state = IB_NAK_INVALID_REQUEST; 2139 qp->r_ack_psn = qp->r_psn; 2140 /* Queue NAK for later */ 2141 if (list_empty(&qp->rspwait)) { 2142 qp->r_flags |= RVT_R_RSP_NAK; 2143 rvt_get_qp(qp); 2144 list_add_tail(&qp->rspwait, &rcd->qp_wait_list); 2145 } 2146 return; 2147 2148 nack_acc_unlck: 2149 spin_unlock_irqrestore(&qp->s_lock, flags); 2150 nack_acc: 2151 rvt_rc_error(qp, IB_WC_LOC_PROT_ERR); 2152 qp->r_nak_state = IB_NAK_REMOTE_ACCESS_ERROR; 2153 qp->r_ack_psn = qp->r_psn; 2154 send_ack: 2155 qib_send_rc_ack(qp); 2156 return; 2157 2158 sunlock: 2159 spin_unlock_irqrestore(&qp->s_lock, flags); 2160 } 2161