1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Shared Memory Communications over RDMA (SMC-R) and RoCE 4 * 5 * IB infrastructure: 6 * Establish SMC-R as an Infiniband Client to be notified about added and 7 * removed IB devices of type RDMA. 8 * Determine device and port characteristics for these IB devices. 9 * 10 * Copyright IBM Corp. 2016 11 * 12 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com> 13 */ 14 15 #include <linux/random.h> 16 #include <linux/workqueue.h> 17 #include <linux/scatterlist.h> 18 #include <rdma/ib_verbs.h> 19 #include <rdma/ib_cache.h> 20 21 #include "smc_pnet.h" 22 #include "smc_ib.h" 23 #include "smc_core.h" 24 #include "smc_wr.h" 25 #include "smc.h" 26 27 #define SMC_MAX_CQE 32766 /* max. # of completion queue elements */ 28 29 #define SMC_QP_MIN_RNR_TIMER 5 30 #define SMC_QP_TIMEOUT 15 /* 4096 * 2 ** timeout usec */ 31 #define SMC_QP_RETRY_CNT 7 /* 7: infinite */ 32 #define SMC_QP_RNR_RETRY 7 /* 7: infinite */ 33 34 struct smc_ib_devices smc_ib_devices = { /* smc-registered ib devices */ 35 .lock = __SPIN_LOCK_UNLOCKED(smc_ib_devices.lock), 36 .list = LIST_HEAD_INIT(smc_ib_devices.list), 37 }; 38 39 #define SMC_LOCAL_SYSTEMID_RESET "%%%%%%%" 40 41 u8 local_systemid[SMC_SYSTEMID_LEN] = SMC_LOCAL_SYSTEMID_RESET; /* unique system 42 * identifier 43 */ 44 45 static int smc_ib_modify_qp_init(struct smc_link *lnk) 46 { 47 struct ib_qp_attr qp_attr; 48 49 memset(&qp_attr, 0, sizeof(qp_attr)); 50 qp_attr.qp_state = IB_QPS_INIT; 51 qp_attr.pkey_index = 0; 52 qp_attr.port_num = lnk->ibport; 53 qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE 54 | IB_ACCESS_REMOTE_WRITE; 55 return ib_modify_qp(lnk->roce_qp, &qp_attr, 56 IB_QP_STATE | IB_QP_PKEY_INDEX | 57 IB_QP_ACCESS_FLAGS | IB_QP_PORT); 58 } 59 60 static int smc_ib_modify_qp_rtr(struct smc_link *lnk) 61 { 62 enum ib_qp_attr_mask qp_attr_mask = 63 IB_QP_STATE | IB_QP_AV | IB_QP_PATH_MTU | IB_QP_DEST_QPN | 64 IB_QP_RQ_PSN | IB_QP_MAX_DEST_RD_ATOMIC | IB_QP_MIN_RNR_TIMER; 65 struct ib_qp_attr qp_attr; 66 67 memset(&qp_attr, 0, sizeof(qp_attr)); 68 qp_attr.qp_state = IB_QPS_RTR; 69 qp_attr.path_mtu = min(lnk->path_mtu, lnk->peer_mtu); 70 qp_attr.ah_attr.type = RDMA_AH_ATTR_TYPE_ROCE; 71 rdma_ah_set_port_num(&qp_attr.ah_attr, lnk->ibport); 72 rdma_ah_set_grh(&qp_attr.ah_attr, NULL, 0, lnk->sgid_index, 1, 0); 73 rdma_ah_set_dgid_raw(&qp_attr.ah_attr, lnk->peer_gid); 74 memcpy(&qp_attr.ah_attr.roce.dmac, lnk->peer_mac, 75 sizeof(lnk->peer_mac)); 76 qp_attr.dest_qp_num = lnk->peer_qpn; 77 qp_attr.rq_psn = lnk->peer_psn; /* starting receive packet seq # */ 78 qp_attr.max_dest_rd_atomic = 1; /* max # of resources for incoming 79 * requests 80 */ 81 qp_attr.min_rnr_timer = SMC_QP_MIN_RNR_TIMER; 82 83 return ib_modify_qp(lnk->roce_qp, &qp_attr, qp_attr_mask); 84 } 85 86 int smc_ib_modify_qp_rts(struct smc_link *lnk) 87 { 88 struct ib_qp_attr qp_attr; 89 90 memset(&qp_attr, 0, sizeof(qp_attr)); 91 qp_attr.qp_state = IB_QPS_RTS; 92 qp_attr.timeout = SMC_QP_TIMEOUT; /* local ack timeout */ 93 qp_attr.retry_cnt = SMC_QP_RETRY_CNT; /* retry count */ 94 qp_attr.rnr_retry = SMC_QP_RNR_RETRY; /* RNR retries, 7=infinite */ 95 qp_attr.sq_psn = lnk->psn_initial; /* starting send packet seq # */ 96 qp_attr.max_rd_atomic = 1; /* # of outstanding RDMA reads and 97 * atomic ops allowed 98 */ 99 return ib_modify_qp(lnk->roce_qp, &qp_attr, 100 IB_QP_STATE | IB_QP_TIMEOUT | IB_QP_RETRY_CNT | 101 IB_QP_SQ_PSN | IB_QP_RNR_RETRY | 102 IB_QP_MAX_QP_RD_ATOMIC); 103 } 104 105 int smc_ib_modify_qp_reset(struct smc_link *lnk) 106 { 107 struct ib_qp_attr qp_attr; 108 109 memset(&qp_attr, 0, sizeof(qp_attr)); 110 qp_attr.qp_state = IB_QPS_RESET; 111 return ib_modify_qp(lnk->roce_qp, &qp_attr, IB_QP_STATE); 112 } 113 114 int smc_ib_ready_link(struct smc_link *lnk) 115 { 116 struct smc_link_group *lgr = smc_get_lgr(lnk); 117 int rc = 0; 118 119 rc = smc_ib_modify_qp_init(lnk); 120 if (rc) 121 goto out; 122 123 rc = smc_ib_modify_qp_rtr(lnk); 124 if (rc) 125 goto out; 126 smc_wr_remember_qp_attr(lnk); 127 rc = ib_req_notify_cq(lnk->smcibdev->roce_cq_recv, 128 IB_CQ_SOLICITED_MASK); 129 if (rc) 130 goto out; 131 rc = smc_wr_rx_post_init(lnk); 132 if (rc) 133 goto out; 134 smc_wr_remember_qp_attr(lnk); 135 136 if (lgr->role == SMC_SERV) { 137 rc = smc_ib_modify_qp_rts(lnk); 138 if (rc) 139 goto out; 140 smc_wr_remember_qp_attr(lnk); 141 } 142 out: 143 return rc; 144 } 145 146 static int smc_ib_fill_mac(struct smc_ib_device *smcibdev, u8 ibport) 147 { 148 struct ib_gid_attr gattr; 149 union ib_gid gid; 150 int rc; 151 152 rc = ib_query_gid(smcibdev->ibdev, ibport, 0, &gid, &gattr); 153 if (rc || !gattr.ndev) 154 return -ENODEV; 155 156 memcpy(smcibdev->mac[ibport - 1], gattr.ndev->dev_addr, ETH_ALEN); 157 dev_put(gattr.ndev); 158 return 0; 159 } 160 161 /* Create an identifier unique for this instance of SMC-R. 162 * The MAC-address of the first active registered IB device 163 * plus a random 2-byte number is used to create this identifier. 164 * This name is delivered to the peer during connection initialization. 165 */ 166 static inline void smc_ib_define_local_systemid(struct smc_ib_device *smcibdev, 167 u8 ibport) 168 { 169 memcpy(&local_systemid[2], &smcibdev->mac[ibport - 1], 170 sizeof(smcibdev->mac[ibport - 1])); 171 get_random_bytes(&local_systemid[0], 2); 172 } 173 174 bool smc_ib_port_active(struct smc_ib_device *smcibdev, u8 ibport) 175 { 176 return smcibdev->pattr[ibport - 1].state == IB_PORT_ACTIVE; 177 } 178 179 /* determine the gid for an ib-device port and vlan id */ 180 int smc_ib_determine_gid(struct smc_ib_device *smcibdev, u8 ibport, 181 unsigned short vlan_id, u8 gid[], u8 *sgid_index) 182 { 183 struct ib_gid_attr gattr; 184 union ib_gid _gid; 185 int i; 186 187 for (i = 0; i < smcibdev->pattr[ibport - 1].gid_tbl_len; i++) { 188 memset(&_gid, 0, SMC_GID_SIZE); 189 memset(&gattr, 0, sizeof(gattr)); 190 if (ib_query_gid(smcibdev->ibdev, ibport, i, &_gid, &gattr)) 191 continue; 192 if (!gattr.ndev) 193 continue; 194 if (((!vlan_id && !is_vlan_dev(gattr.ndev)) || 195 (vlan_id && is_vlan_dev(gattr.ndev) && 196 vlan_dev_vlan_id(gattr.ndev) == vlan_id)) && 197 gattr.gid_type == IB_GID_TYPE_IB) { 198 if (gid) 199 memcpy(gid, &_gid, SMC_GID_SIZE); 200 if (sgid_index) 201 *sgid_index = i; 202 dev_put(gattr.ndev); 203 return 0; 204 } 205 dev_put(gattr.ndev); 206 } 207 return -ENODEV; 208 } 209 210 static int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport) 211 { 212 int rc; 213 214 memset(&smcibdev->pattr[ibport - 1], 0, 215 sizeof(smcibdev->pattr[ibport - 1])); 216 rc = ib_query_port(smcibdev->ibdev, ibport, 217 &smcibdev->pattr[ibport - 1]); 218 if (rc) 219 goto out; 220 /* the SMC protocol requires specification of the RoCE MAC address */ 221 rc = smc_ib_fill_mac(smcibdev, ibport); 222 if (rc) 223 goto out; 224 if (!strncmp(local_systemid, SMC_LOCAL_SYSTEMID_RESET, 225 sizeof(local_systemid)) && 226 smc_ib_port_active(smcibdev, ibport)) 227 /* create unique system identifier */ 228 smc_ib_define_local_systemid(smcibdev, ibport); 229 out: 230 return rc; 231 } 232 233 /* process context wrapper for might_sleep smc_ib_remember_port_attr */ 234 static void smc_ib_port_event_work(struct work_struct *work) 235 { 236 struct smc_ib_device *smcibdev = container_of( 237 work, struct smc_ib_device, port_event_work); 238 u8 port_idx; 239 240 for_each_set_bit(port_idx, &smcibdev->port_event_mask, SMC_MAX_PORTS) { 241 smc_ib_remember_port_attr(smcibdev, port_idx + 1); 242 clear_bit(port_idx, &smcibdev->port_event_mask); 243 if (!smc_ib_port_active(smcibdev, port_idx + 1)) 244 smc_port_terminate(smcibdev, port_idx + 1); 245 } 246 } 247 248 /* can be called in IRQ context */ 249 static void smc_ib_global_event_handler(struct ib_event_handler *handler, 250 struct ib_event *ibevent) 251 { 252 struct smc_ib_device *smcibdev; 253 u8 port_idx; 254 255 smcibdev = container_of(handler, struct smc_ib_device, event_handler); 256 257 switch (ibevent->event) { 258 case IB_EVENT_PORT_ERR: 259 case IB_EVENT_DEVICE_FATAL: 260 case IB_EVENT_PORT_ACTIVE: 261 port_idx = ibevent->element.port_num - 1; 262 set_bit(port_idx, &smcibdev->port_event_mask); 263 schedule_work(&smcibdev->port_event_work); 264 break; 265 default: 266 break; 267 } 268 } 269 270 void smc_ib_dealloc_protection_domain(struct smc_link *lnk) 271 { 272 if (lnk->roce_pd) 273 ib_dealloc_pd(lnk->roce_pd); 274 lnk->roce_pd = NULL; 275 } 276 277 int smc_ib_create_protection_domain(struct smc_link *lnk) 278 { 279 int rc; 280 281 lnk->roce_pd = ib_alloc_pd(lnk->smcibdev->ibdev, 0); 282 rc = PTR_ERR_OR_ZERO(lnk->roce_pd); 283 if (IS_ERR(lnk->roce_pd)) 284 lnk->roce_pd = NULL; 285 return rc; 286 } 287 288 static void smc_ib_qp_event_handler(struct ib_event *ibevent, void *priv) 289 { 290 struct smc_ib_device *smcibdev = 291 (struct smc_ib_device *)ibevent->device; 292 u8 port_idx; 293 294 switch (ibevent->event) { 295 case IB_EVENT_DEVICE_FATAL: 296 case IB_EVENT_GID_CHANGE: 297 case IB_EVENT_PORT_ERR: 298 case IB_EVENT_QP_ACCESS_ERR: 299 port_idx = ibevent->element.port_num - 1; 300 set_bit(port_idx, &smcibdev->port_event_mask); 301 schedule_work(&smcibdev->port_event_work); 302 break; 303 default: 304 break; 305 } 306 } 307 308 void smc_ib_destroy_queue_pair(struct smc_link *lnk) 309 { 310 if (lnk->roce_qp) 311 ib_destroy_qp(lnk->roce_qp); 312 lnk->roce_qp = NULL; 313 } 314 315 /* create a queue pair within the protection domain for a link */ 316 int smc_ib_create_queue_pair(struct smc_link *lnk) 317 { 318 struct ib_qp_init_attr qp_attr = { 319 .event_handler = smc_ib_qp_event_handler, 320 .qp_context = lnk, 321 .send_cq = lnk->smcibdev->roce_cq_send, 322 .recv_cq = lnk->smcibdev->roce_cq_recv, 323 .srq = NULL, 324 .cap = { 325 /* include unsolicited rdma_writes as well, 326 * there are max. 2 RDMA_WRITE per 1 WR_SEND 327 */ 328 .max_send_wr = SMC_WR_BUF_CNT * 3, 329 .max_recv_wr = SMC_WR_BUF_CNT * 3, 330 .max_send_sge = SMC_IB_MAX_SEND_SGE, 331 .max_recv_sge = 1, 332 }, 333 .sq_sig_type = IB_SIGNAL_REQ_WR, 334 .qp_type = IB_QPT_RC, 335 }; 336 int rc; 337 338 lnk->roce_qp = ib_create_qp(lnk->roce_pd, &qp_attr); 339 rc = PTR_ERR_OR_ZERO(lnk->roce_qp); 340 if (IS_ERR(lnk->roce_qp)) 341 lnk->roce_qp = NULL; 342 else 343 smc_wr_remember_qp_attr(lnk); 344 return rc; 345 } 346 347 void smc_ib_put_memory_region(struct ib_mr *mr) 348 { 349 ib_dereg_mr(mr); 350 } 351 352 static int smc_ib_map_mr_sg(struct smc_buf_desc *buf_slot) 353 { 354 unsigned int offset = 0; 355 int sg_num; 356 357 /* map the largest prefix of a dma mapped SG list */ 358 sg_num = ib_map_mr_sg(buf_slot->mr_rx[SMC_SINGLE_LINK], 359 buf_slot->sgt[SMC_SINGLE_LINK].sgl, 360 buf_slot->sgt[SMC_SINGLE_LINK].orig_nents, 361 &offset, PAGE_SIZE); 362 363 return sg_num; 364 } 365 366 /* Allocate a memory region and map the dma mapped SG list of buf_slot */ 367 int smc_ib_get_memory_region(struct ib_pd *pd, int access_flags, 368 struct smc_buf_desc *buf_slot) 369 { 370 if (buf_slot->mr_rx[SMC_SINGLE_LINK]) 371 return 0; /* already done */ 372 373 buf_slot->mr_rx[SMC_SINGLE_LINK] = 374 ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, 1 << buf_slot->order); 375 if (IS_ERR(buf_slot->mr_rx[SMC_SINGLE_LINK])) { 376 int rc; 377 378 rc = PTR_ERR(buf_slot->mr_rx[SMC_SINGLE_LINK]); 379 buf_slot->mr_rx[SMC_SINGLE_LINK] = NULL; 380 return rc; 381 } 382 383 if (smc_ib_map_mr_sg(buf_slot) != 1) 384 return -EINVAL; 385 386 return 0; 387 } 388 389 /* synchronize buffer usage for cpu access */ 390 void smc_ib_sync_sg_for_cpu(struct smc_ib_device *smcibdev, 391 struct smc_buf_desc *buf_slot, 392 enum dma_data_direction data_direction) 393 { 394 struct scatterlist *sg; 395 unsigned int i; 396 397 /* for now there is just one DMA address */ 398 for_each_sg(buf_slot->sgt[SMC_SINGLE_LINK].sgl, sg, 399 buf_slot->sgt[SMC_SINGLE_LINK].nents, i) { 400 if (!sg_dma_len(sg)) 401 break; 402 ib_dma_sync_single_for_cpu(smcibdev->ibdev, 403 sg_dma_address(sg), 404 sg_dma_len(sg), 405 data_direction); 406 } 407 } 408 409 /* synchronize buffer usage for device access */ 410 void smc_ib_sync_sg_for_device(struct smc_ib_device *smcibdev, 411 struct smc_buf_desc *buf_slot, 412 enum dma_data_direction data_direction) 413 { 414 struct scatterlist *sg; 415 unsigned int i; 416 417 /* for now there is just one DMA address */ 418 for_each_sg(buf_slot->sgt[SMC_SINGLE_LINK].sgl, sg, 419 buf_slot->sgt[SMC_SINGLE_LINK].nents, i) { 420 if (!sg_dma_len(sg)) 421 break; 422 ib_dma_sync_single_for_device(smcibdev->ibdev, 423 sg_dma_address(sg), 424 sg_dma_len(sg), 425 data_direction); 426 } 427 } 428 429 /* Map a new TX or RX buffer SG-table to DMA */ 430 int smc_ib_buf_map_sg(struct smc_ib_device *smcibdev, 431 struct smc_buf_desc *buf_slot, 432 enum dma_data_direction data_direction) 433 { 434 int mapped_nents; 435 436 mapped_nents = ib_dma_map_sg(smcibdev->ibdev, 437 buf_slot->sgt[SMC_SINGLE_LINK].sgl, 438 buf_slot->sgt[SMC_SINGLE_LINK].orig_nents, 439 data_direction); 440 if (!mapped_nents) 441 return -ENOMEM; 442 443 return mapped_nents; 444 } 445 446 void smc_ib_buf_unmap_sg(struct smc_ib_device *smcibdev, 447 struct smc_buf_desc *buf_slot, 448 enum dma_data_direction data_direction) 449 { 450 if (!buf_slot->sgt[SMC_SINGLE_LINK].sgl->dma_address) 451 return; /* already unmapped */ 452 453 ib_dma_unmap_sg(smcibdev->ibdev, 454 buf_slot->sgt[SMC_SINGLE_LINK].sgl, 455 buf_slot->sgt[SMC_SINGLE_LINK].orig_nents, 456 data_direction); 457 buf_slot->sgt[SMC_SINGLE_LINK].sgl->dma_address = 0; 458 } 459 460 long smc_ib_setup_per_ibdev(struct smc_ib_device *smcibdev) 461 { 462 struct ib_cq_init_attr cqattr = { 463 .cqe = SMC_MAX_CQE, .comp_vector = 0 }; 464 int cqe_size_order, smc_order; 465 long rc; 466 467 /* the calculated number of cq entries fits to mlx5 cq allocation */ 468 cqe_size_order = cache_line_size() == 128 ? 7 : 6; 469 smc_order = MAX_ORDER - cqe_size_order - 1; 470 if (SMC_MAX_CQE + 2 > (0x00000001 << smc_order) * PAGE_SIZE) 471 cqattr.cqe = (0x00000001 << smc_order) * PAGE_SIZE - 2; 472 smcibdev->roce_cq_send = ib_create_cq(smcibdev->ibdev, 473 smc_wr_tx_cq_handler, NULL, 474 smcibdev, &cqattr); 475 rc = PTR_ERR_OR_ZERO(smcibdev->roce_cq_send); 476 if (IS_ERR(smcibdev->roce_cq_send)) { 477 smcibdev->roce_cq_send = NULL; 478 return rc; 479 } 480 smcibdev->roce_cq_recv = ib_create_cq(smcibdev->ibdev, 481 smc_wr_rx_cq_handler, NULL, 482 smcibdev, &cqattr); 483 rc = PTR_ERR_OR_ZERO(smcibdev->roce_cq_recv); 484 if (IS_ERR(smcibdev->roce_cq_recv)) { 485 smcibdev->roce_cq_recv = NULL; 486 goto err; 487 } 488 smc_wr_add_dev(smcibdev); 489 smcibdev->initialized = 1; 490 return rc; 491 492 err: 493 ib_destroy_cq(smcibdev->roce_cq_send); 494 return rc; 495 } 496 497 static void smc_ib_cleanup_per_ibdev(struct smc_ib_device *smcibdev) 498 { 499 if (!smcibdev->initialized) 500 return; 501 smcibdev->initialized = 0; 502 smc_wr_remove_dev(smcibdev); 503 ib_destroy_cq(smcibdev->roce_cq_recv); 504 ib_destroy_cq(smcibdev->roce_cq_send); 505 } 506 507 static struct ib_client smc_ib_client; 508 509 /* callback function for ib_register_client() */ 510 static void smc_ib_add_dev(struct ib_device *ibdev) 511 { 512 struct smc_ib_device *smcibdev; 513 u8 port_cnt; 514 int i; 515 516 if (ibdev->node_type != RDMA_NODE_IB_CA) 517 return; 518 519 smcibdev = kzalloc(sizeof(*smcibdev), GFP_KERNEL); 520 if (!smcibdev) 521 return; 522 523 smcibdev->ibdev = ibdev; 524 INIT_WORK(&smcibdev->port_event_work, smc_ib_port_event_work); 525 526 spin_lock(&smc_ib_devices.lock); 527 list_add_tail(&smcibdev->list, &smc_ib_devices.list); 528 spin_unlock(&smc_ib_devices.lock); 529 ib_set_client_data(ibdev, &smc_ib_client, smcibdev); 530 INIT_IB_EVENT_HANDLER(&smcibdev->event_handler, smcibdev->ibdev, 531 smc_ib_global_event_handler); 532 ib_register_event_handler(&smcibdev->event_handler); 533 534 /* trigger reading of the port attributes */ 535 port_cnt = smcibdev->ibdev->phys_port_cnt; 536 for (i = 0; 537 i < min_t(size_t, port_cnt, SMC_MAX_PORTS); 538 i++) { 539 set_bit(i, &smcibdev->port_event_mask); 540 /* determine pnetids of the port */ 541 smc_pnetid_by_dev_port(ibdev->dev.parent, i, 542 smcibdev->pnetid[i]); 543 } 544 schedule_work(&smcibdev->port_event_work); 545 } 546 547 /* callback function for ib_register_client() */ 548 static void smc_ib_remove_dev(struct ib_device *ibdev, void *client_data) 549 { 550 struct smc_ib_device *smcibdev; 551 552 smcibdev = ib_get_client_data(ibdev, &smc_ib_client); 553 ib_set_client_data(ibdev, &smc_ib_client, NULL); 554 spin_lock(&smc_ib_devices.lock); 555 list_del_init(&smcibdev->list); /* remove from smc_ib_devices */ 556 spin_unlock(&smc_ib_devices.lock); 557 smc_pnet_remove_by_ibdev(smcibdev); 558 smc_ib_cleanup_per_ibdev(smcibdev); 559 ib_unregister_event_handler(&smcibdev->event_handler); 560 kfree(smcibdev); 561 } 562 563 static struct ib_client smc_ib_client = { 564 .name = "smc_ib", 565 .add = smc_ib_add_dev, 566 .remove = smc_ib_remove_dev, 567 }; 568 569 int __init smc_ib_register_client(void) 570 { 571 return ib_register_client(&smc_ib_client); 572 } 573 574 void smc_ib_unregister_client(void) 575 { 576 ib_unregister_client(&smc_ib_client); 577 } 578