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