1 // SPDX-License-Identifier: GPL-2.0 2 /* Shared Memory Communications Direct over ISM devices (SMC-D) 3 * 4 * Functions for ISM device. 5 * 6 * Copyright IBM Corp. 2018 7 */ 8 9 #include <linux/if_vlan.h> 10 #include <linux/spinlock.h> 11 #include <linux/mutex.h> 12 #include <linux/slab.h> 13 #include <asm/page.h> 14 15 #include "smc.h" 16 #include "smc_core.h" 17 #include "smc_ism.h" 18 #include "smc_pnet.h" 19 #include "smc_netlink.h" 20 21 struct smcd_dev_list smcd_dev_list = { 22 .list = LIST_HEAD_INIT(smcd_dev_list.list), 23 .mutex = __MUTEX_INITIALIZER(smcd_dev_list.mutex) 24 }; 25 26 static bool smc_ism_v2_capable; 27 static u8 smc_ism_v2_system_eid[SMC_MAX_EID_LEN]; 28 29 /* Test if an ISM communication is possible - same CPC */ 30 int smc_ism_cantalk(u64 peer_gid, unsigned short vlan_id, struct smcd_dev *smcd) 31 { 32 return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0, 33 vlan_id); 34 } 35 36 int smc_ism_write(struct smcd_dev *smcd, const struct smc_ism_position *pos, 37 void *data, size_t len) 38 { 39 int rc; 40 41 rc = smcd->ops->move_data(smcd, pos->token, pos->index, pos->signal, 42 pos->offset, data, len); 43 44 return rc < 0 ? rc : 0; 45 } 46 47 void smc_ism_get_system_eid(u8 **eid) 48 { 49 if (!smc_ism_v2_capable) 50 *eid = NULL; 51 else 52 *eid = smc_ism_v2_system_eid; 53 } 54 55 u16 smc_ism_get_chid(struct smcd_dev *smcd) 56 { 57 return smcd->ops->get_chid(smcd); 58 } 59 60 /* HW supports ISM V2 and thus System EID is defined */ 61 bool smc_ism_is_v2_capable(void) 62 { 63 return smc_ism_v2_capable; 64 } 65 66 /* Set a connection using this DMBE. */ 67 void smc_ism_set_conn(struct smc_connection *conn) 68 { 69 unsigned long flags; 70 71 spin_lock_irqsave(&conn->lgr->smcd->lock, flags); 72 conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn; 73 spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags); 74 } 75 76 /* Unset a connection using this DMBE. */ 77 void smc_ism_unset_conn(struct smc_connection *conn) 78 { 79 unsigned long flags; 80 81 if (!conn->rmb_desc) 82 return; 83 84 spin_lock_irqsave(&conn->lgr->smcd->lock, flags); 85 conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL; 86 spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags); 87 } 88 89 /* Register a VLAN identifier with the ISM device. Use a reference count 90 * and add a VLAN identifier only when the first DMB using this VLAN is 91 * registered. 92 */ 93 int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid) 94 { 95 struct smc_ism_vlanid *new_vlan, *vlan; 96 unsigned long flags; 97 int rc = 0; 98 99 if (!vlanid) /* No valid vlan id */ 100 return -EINVAL; 101 102 /* create new vlan entry, in case we need it */ 103 new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL); 104 if (!new_vlan) 105 return -ENOMEM; 106 new_vlan->vlanid = vlanid; 107 refcount_set(&new_vlan->refcnt, 1); 108 109 /* if there is an existing entry, increase count and return */ 110 spin_lock_irqsave(&smcd->lock, flags); 111 list_for_each_entry(vlan, &smcd->vlan, list) { 112 if (vlan->vlanid == vlanid) { 113 refcount_inc(&vlan->refcnt); 114 kfree(new_vlan); 115 goto out; 116 } 117 } 118 119 /* no existing entry found. 120 * add new entry to device; might fail, e.g., if HW limit reached 121 */ 122 if (smcd->ops->add_vlan_id(smcd, vlanid)) { 123 kfree(new_vlan); 124 rc = -EIO; 125 goto out; 126 } 127 list_add_tail(&new_vlan->list, &smcd->vlan); 128 out: 129 spin_unlock_irqrestore(&smcd->lock, flags); 130 return rc; 131 } 132 133 /* Unregister a VLAN identifier with the ISM device. Use a reference count 134 * and remove a VLAN identifier only when the last DMB using this VLAN is 135 * unregistered. 136 */ 137 int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid) 138 { 139 struct smc_ism_vlanid *vlan; 140 unsigned long flags; 141 bool found = false; 142 int rc = 0; 143 144 if (!vlanid) /* No valid vlan id */ 145 return -EINVAL; 146 147 spin_lock_irqsave(&smcd->lock, flags); 148 list_for_each_entry(vlan, &smcd->vlan, list) { 149 if (vlan->vlanid == vlanid) { 150 if (!refcount_dec_and_test(&vlan->refcnt)) 151 goto out; 152 found = true; 153 break; 154 } 155 } 156 if (!found) { 157 rc = -ENOENT; 158 goto out; /* VLAN id not in table */ 159 } 160 161 /* Found and the last reference just gone */ 162 if (smcd->ops->del_vlan_id(smcd, vlanid)) 163 rc = -EIO; 164 list_del(&vlan->list); 165 kfree(vlan); 166 out: 167 spin_unlock_irqrestore(&smcd->lock, flags); 168 return rc; 169 } 170 171 int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc) 172 { 173 struct smcd_dmb dmb; 174 int rc = 0; 175 176 if (!dmb_desc->dma_addr) 177 return rc; 178 179 memset(&dmb, 0, sizeof(dmb)); 180 dmb.dmb_tok = dmb_desc->token; 181 dmb.sba_idx = dmb_desc->sba_idx; 182 dmb.cpu_addr = dmb_desc->cpu_addr; 183 dmb.dma_addr = dmb_desc->dma_addr; 184 dmb.dmb_len = dmb_desc->len; 185 rc = smcd->ops->unregister_dmb(smcd, &dmb); 186 if (!rc || rc == ISM_ERROR) { 187 dmb_desc->cpu_addr = NULL; 188 dmb_desc->dma_addr = 0; 189 } 190 191 return rc; 192 } 193 194 int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len, 195 struct smc_buf_desc *dmb_desc) 196 { 197 struct smcd_dmb dmb; 198 int rc; 199 200 memset(&dmb, 0, sizeof(dmb)); 201 dmb.dmb_len = dmb_len; 202 dmb.sba_idx = dmb_desc->sba_idx; 203 dmb.vlan_id = lgr->vlan_id; 204 dmb.rgid = lgr->peer_gid; 205 rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb); 206 if (!rc) { 207 dmb_desc->sba_idx = dmb.sba_idx; 208 dmb_desc->token = dmb.dmb_tok; 209 dmb_desc->cpu_addr = dmb.cpu_addr; 210 dmb_desc->dma_addr = dmb.dma_addr; 211 dmb_desc->len = dmb.dmb_len; 212 } 213 return rc; 214 } 215 216 static int smc_nl_handle_smcd_dev(struct smcd_dev *smcd, 217 struct sk_buff *skb, 218 struct netlink_callback *cb) 219 { 220 char smc_pnet[SMC_MAX_PNETID_LEN + 1]; 221 struct smc_pci_dev smc_pci_dev; 222 struct nlattr *port_attrs; 223 struct nlattr *attrs; 224 int use_cnt = 0; 225 void *nlh; 226 227 nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, 228 &smc_gen_nl_family, NLM_F_MULTI, 229 SMC_NETLINK_GET_DEV_SMCD); 230 if (!nlh) 231 goto errmsg; 232 attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCD); 233 if (!attrs) 234 goto errout; 235 use_cnt = atomic_read(&smcd->lgr_cnt); 236 if (nla_put_u32(skb, SMC_NLA_DEV_USE_CNT, use_cnt)) 237 goto errattr; 238 if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, use_cnt > 0)) 239 goto errattr; 240 memset(&smc_pci_dev, 0, sizeof(smc_pci_dev)); 241 smc_set_pci_values(to_pci_dev(smcd->dev.parent), &smc_pci_dev); 242 if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev.pci_fid)) 243 goto errattr; 244 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev.pci_pchid)) 245 goto errattr; 246 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev.pci_vendor)) 247 goto errattr; 248 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev.pci_device)) 249 goto errattr; 250 if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev.pci_id)) 251 goto errattr; 252 253 port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT); 254 if (!port_attrs) 255 goto errattr; 256 if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR, smcd->pnetid_by_user)) 257 goto errportattr; 258 memcpy(smc_pnet, smcd->pnetid, SMC_MAX_PNETID_LEN); 259 smc_pnet[SMC_MAX_PNETID_LEN] = 0; 260 if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet)) 261 goto errportattr; 262 263 nla_nest_end(skb, port_attrs); 264 nla_nest_end(skb, attrs); 265 genlmsg_end(skb, nlh); 266 return 0; 267 268 errportattr: 269 nla_nest_cancel(skb, port_attrs); 270 errattr: 271 nla_nest_cancel(skb, attrs); 272 errout: 273 nlmsg_cancel(skb, nlh); 274 errmsg: 275 return -EMSGSIZE; 276 } 277 278 static void smc_nl_prep_smcd_dev(struct smcd_dev_list *dev_list, 279 struct sk_buff *skb, 280 struct netlink_callback *cb) 281 { 282 struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); 283 int snum = cb_ctx->pos[0]; 284 struct smcd_dev *smcd; 285 int num = 0; 286 287 mutex_lock(&dev_list->mutex); 288 list_for_each_entry(smcd, &dev_list->list, list) { 289 if (num < snum) 290 goto next; 291 if (smc_nl_handle_smcd_dev(smcd, skb, cb)) 292 goto errout; 293 next: 294 num++; 295 } 296 errout: 297 mutex_unlock(&dev_list->mutex); 298 cb_ctx->pos[0] = num; 299 } 300 301 int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb) 302 { 303 smc_nl_prep_smcd_dev(&smcd_dev_list, skb, cb); 304 return skb->len; 305 } 306 307 struct smc_ism_event_work { 308 struct work_struct work; 309 struct smcd_dev *smcd; 310 struct smcd_event event; 311 }; 312 313 #define ISM_EVENT_REQUEST 0x0001 314 #define ISM_EVENT_RESPONSE 0x0002 315 #define ISM_EVENT_REQUEST_IR 0x00000001 316 #define ISM_EVENT_CODE_SHUTDOWN 0x80 317 #define ISM_EVENT_CODE_TESTLINK 0x83 318 319 union smcd_sw_event_info { 320 u64 info; 321 struct { 322 u8 uid[SMC_LGR_ID_SIZE]; 323 unsigned short vlan_id; 324 u16 code; 325 }; 326 }; 327 328 static void smcd_handle_sw_event(struct smc_ism_event_work *wrk) 329 { 330 union smcd_sw_event_info ev_info; 331 332 ev_info.info = wrk->event.info; 333 switch (wrk->event.code) { 334 case ISM_EVENT_CODE_SHUTDOWN: /* Peer shut down DMBs */ 335 smc_smcd_terminate(wrk->smcd, wrk->event.tok, ev_info.vlan_id); 336 break; 337 case ISM_EVENT_CODE_TESTLINK: /* Activity timer */ 338 if (ev_info.code == ISM_EVENT_REQUEST) { 339 ev_info.code = ISM_EVENT_RESPONSE; 340 wrk->smcd->ops->signal_event(wrk->smcd, 341 wrk->event.tok, 342 ISM_EVENT_REQUEST_IR, 343 ISM_EVENT_CODE_TESTLINK, 344 ev_info.info); 345 } 346 break; 347 } 348 } 349 350 int smc_ism_signal_shutdown(struct smc_link_group *lgr) 351 { 352 int rc; 353 union smcd_sw_event_info ev_info; 354 355 if (lgr->peer_shutdown) 356 return 0; 357 358 memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE); 359 ev_info.vlan_id = lgr->vlan_id; 360 ev_info.code = ISM_EVENT_REQUEST; 361 rc = lgr->smcd->ops->signal_event(lgr->smcd, lgr->peer_gid, 362 ISM_EVENT_REQUEST_IR, 363 ISM_EVENT_CODE_SHUTDOWN, 364 ev_info.info); 365 return rc; 366 } 367 368 /* worker for SMC-D events */ 369 static void smc_ism_event_work(struct work_struct *work) 370 { 371 struct smc_ism_event_work *wrk = 372 container_of(work, struct smc_ism_event_work, work); 373 374 switch (wrk->event.type) { 375 case ISM_EVENT_GID: /* GID event, token is peer GID */ 376 smc_smcd_terminate(wrk->smcd, wrk->event.tok, VLAN_VID_MASK); 377 break; 378 case ISM_EVENT_DMB: 379 break; 380 case ISM_EVENT_SWR: /* Software defined event */ 381 smcd_handle_sw_event(wrk); 382 break; 383 } 384 kfree(wrk); 385 } 386 387 static void smcd_release(struct device *dev) 388 { 389 struct smcd_dev *smcd = container_of(dev, struct smcd_dev, dev); 390 391 kfree(smcd->conn); 392 kfree(smcd); 393 } 394 395 struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name, 396 const struct smcd_ops *ops, int max_dmbs) 397 { 398 struct smcd_dev *smcd; 399 400 smcd = kzalloc(sizeof(*smcd), GFP_KERNEL); 401 if (!smcd) 402 return NULL; 403 smcd->conn = kcalloc(max_dmbs, sizeof(struct smc_connection *), 404 GFP_KERNEL); 405 if (!smcd->conn) { 406 kfree(smcd); 407 return NULL; 408 } 409 410 smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)", 411 WQ_MEM_RECLAIM, name); 412 if (!smcd->event_wq) { 413 kfree(smcd->conn); 414 kfree(smcd); 415 return NULL; 416 } 417 418 smcd->dev.parent = parent; 419 smcd->dev.release = smcd_release; 420 device_initialize(&smcd->dev); 421 dev_set_name(&smcd->dev, name); 422 smcd->ops = ops; 423 if (smc_pnetid_by_dev_port(parent, 0, smcd->pnetid)) 424 smc_pnetid_by_table_smcd(smcd); 425 426 spin_lock_init(&smcd->lock); 427 spin_lock_init(&smcd->lgr_lock); 428 INIT_LIST_HEAD(&smcd->vlan); 429 INIT_LIST_HEAD(&smcd->lgr_list); 430 init_waitqueue_head(&smcd->lgrs_deleted); 431 return smcd; 432 } 433 EXPORT_SYMBOL_GPL(smcd_alloc_dev); 434 435 int smcd_register_dev(struct smcd_dev *smcd) 436 { 437 int rc; 438 439 mutex_lock(&smcd_dev_list.mutex); 440 if (list_empty(&smcd_dev_list.list)) { 441 u8 *system_eid = NULL; 442 443 smcd->ops->get_system_eid(smcd, &system_eid); 444 if (system_eid[24] != '0' || system_eid[28] != '0') { 445 smc_ism_v2_capable = true; 446 memcpy(smc_ism_v2_system_eid, system_eid, 447 SMC_MAX_EID_LEN); 448 } 449 } 450 /* sort list: devices without pnetid before devices with pnetid */ 451 if (smcd->pnetid[0]) 452 list_add_tail(&smcd->list, &smcd_dev_list.list); 453 else 454 list_add(&smcd->list, &smcd_dev_list.list); 455 mutex_unlock(&smcd_dev_list.mutex); 456 457 pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n", 458 dev_name(&smcd->dev), smcd->pnetid, 459 smcd->pnetid_by_user ? " (user defined)" : ""); 460 461 rc = device_add(&smcd->dev); 462 if (rc) { 463 mutex_lock(&smcd_dev_list.mutex); 464 list_del(&smcd->list); 465 mutex_unlock(&smcd_dev_list.mutex); 466 } 467 468 return rc; 469 } 470 EXPORT_SYMBOL_GPL(smcd_register_dev); 471 472 void smcd_unregister_dev(struct smcd_dev *smcd) 473 { 474 pr_warn_ratelimited("smc: removing smcd device %s\n", 475 dev_name(&smcd->dev)); 476 mutex_lock(&smcd_dev_list.mutex); 477 list_del_init(&smcd->list); 478 mutex_unlock(&smcd_dev_list.mutex); 479 smcd->going_away = 1; 480 smc_smcd_terminate_all(smcd); 481 destroy_workqueue(smcd->event_wq); 482 483 device_del(&smcd->dev); 484 } 485 EXPORT_SYMBOL_GPL(smcd_unregister_dev); 486 487 void smcd_free_dev(struct smcd_dev *smcd) 488 { 489 put_device(&smcd->dev); 490 } 491 EXPORT_SYMBOL_GPL(smcd_free_dev); 492 493 /* SMCD Device event handler. Called from ISM device interrupt handler. 494 * Parameters are smcd device pointer, 495 * - event->type (0 --> DMB, 1 --> GID), 496 * - event->code (event code), 497 * - event->tok (either DMB token when event type 0, or GID when event type 1) 498 * - event->time (time of day) 499 * - event->info (debug info). 500 * 501 * Context: 502 * - Function called in IRQ context from ISM device driver event handler. 503 */ 504 void smcd_handle_event(struct smcd_dev *smcd, struct smcd_event *event) 505 { 506 struct smc_ism_event_work *wrk; 507 508 if (smcd->going_away) 509 return; 510 /* copy event to event work queue, and let it be handled there */ 511 wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC); 512 if (!wrk) 513 return; 514 INIT_WORK(&wrk->work, smc_ism_event_work); 515 wrk->smcd = smcd; 516 wrk->event = *event; 517 queue_work(smcd->event_wq, &wrk->work); 518 } 519 EXPORT_SYMBOL_GPL(smcd_handle_event); 520 521 /* SMCD Device interrupt handler. Called from ISM device interrupt handler. 522 * Parameters are smcd device pointer and DMB number. Find the connection and 523 * schedule the tasklet for this connection. 524 * 525 * Context: 526 * - Function called in IRQ context from ISM device driver IRQ handler. 527 */ 528 void smcd_handle_irq(struct smcd_dev *smcd, unsigned int dmbno) 529 { 530 struct smc_connection *conn = NULL; 531 unsigned long flags; 532 533 spin_lock_irqsave(&smcd->lock, flags); 534 conn = smcd->conn[dmbno]; 535 if (conn && !conn->killed) 536 tasklet_schedule(&conn->rx_tsklet); 537 spin_unlock_irqrestore(&smcd->lock, flags); 538 } 539 EXPORT_SYMBOL_GPL(smcd_handle_irq); 540 541 void __init smc_ism_init(void) 542 { 543 smc_ism_v2_capable = false; 544 memset(smc_ism_v2_system_eid, 0, SMC_MAX_EID_LEN); 545 } 546