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