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