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#include "linux/ism.h" 21 22struct smcd_dev_list smcd_dev_list = { 23 .list = LIST_HEAD_INIT(smcd_dev_list.list), 24 .mutex = __MUTEX_INITIALIZER(smcd_dev_list.mutex) 25}; 26 27static bool smc_ism_v2_capable; 28static u8 smc_ism_v2_system_eid[SMC_MAX_EID_LEN]; 29 30#if IS_ENABLED(CONFIG_ISM) 31static void smcd_register_dev(struct ism_dev *ism); 32static void smcd_unregister_dev(struct ism_dev *ism); 33static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event); 34static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno, 35 u16 dmbemask); 36 37static struct ism_client smc_ism_client = { 38 .name = "SMC-D", 39 .add = smcd_register_dev, 40 .remove = smcd_unregister_dev, 41 .handle_event = smcd_handle_event, 42 .handle_irq = smcd_handle_irq, 43}; 44#endif 45 46static void smc_ism_create_system_eid(void) 47{ 48 struct smc_ism_seid *seid = 49 (struct smc_ism_seid *)smc_ism_v2_system_eid; 50#if IS_ENABLED(CONFIG_S390) 51 struct cpuid id; 52 u16 ident_tail; 53 char tmp[5]; 54 55 memcpy(seid->seid_string, "IBM-SYSZ-ISMSEID00000000", 24); 56 get_cpu_id(&id); 57 ident_tail = (u16)(id.ident & SMC_ISM_IDENT_MASK); 58 snprintf(tmp, 5, "%04X", ident_tail); 59 memcpy(seid->serial_number, tmp, 4); 60 snprintf(tmp, 5, "%04X", id.machine); 61 memcpy(seid->type, tmp, 4); 62#else 63 memset(seid, 0, SMC_MAX_EID_LEN); 64#endif 65} 66 67/* Test if an ISM communication is possible - same CPC */ 68int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id, 69 struct smcd_dev *smcd) 70{ 71 return smcd->ops->query_remote_gid(smcd, peer_gid, vlan_id ? 1 : 0, 72 vlan_id); 73} 74 75void smc_ism_get_system_eid(u8 **eid) 76{ 77 if (!smc_ism_v2_capable) 78 *eid = NULL; 79 else 80 *eid = smc_ism_v2_system_eid; 81} 82 83u16 smc_ism_get_chid(struct smcd_dev *smcd) 84{ 85 return smcd->ops->get_chid(smcd); 86} 87 88/* HW supports ISM V2 and thus System EID is defined */ 89bool smc_ism_is_v2_capable(void) 90{ 91 return smc_ism_v2_capable; 92} 93 94/* Set a connection using this DMBE. */ 95void smc_ism_set_conn(struct smc_connection *conn) 96{ 97 unsigned long flags; 98 99 spin_lock_irqsave(&conn->lgr->smcd->lock, flags); 100 conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn; 101 spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags); 102} 103 104/* Unset a connection using this DMBE. */ 105void smc_ism_unset_conn(struct smc_connection *conn) 106{ 107 unsigned long flags; 108 109 if (!conn->rmb_desc) 110 return; 111 112 spin_lock_irqsave(&conn->lgr->smcd->lock, flags); 113 conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL; 114 spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags); 115} 116 117/* Register a VLAN identifier with the ISM device. Use a reference count 118 * and add a VLAN identifier only when the first DMB using this VLAN is 119 * registered. 120 */ 121int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid) 122{ 123 struct smc_ism_vlanid *new_vlan, *vlan; 124 unsigned long flags; 125 int rc = 0; 126 127 if (!vlanid) /* No valid vlan id */ 128 return -EINVAL; 129 130 /* create new vlan entry, in case we need it */ 131 new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL); 132 if (!new_vlan) 133 return -ENOMEM; 134 new_vlan->vlanid = vlanid; 135 refcount_set(&new_vlan->refcnt, 1); 136 137 /* if there is an existing entry, increase count and return */ 138 spin_lock_irqsave(&smcd->lock, flags); 139 list_for_each_entry(vlan, &smcd->vlan, list) { 140 if (vlan->vlanid == vlanid) { 141 refcount_inc(&vlan->refcnt); 142 kfree(new_vlan); 143 goto out; 144 } 145 } 146 147 /* no existing entry found. 148 * add new entry to device; might fail, e.g., if HW limit reached 149 */ 150 if (smcd->ops->add_vlan_id(smcd, vlanid)) { 151 kfree(new_vlan); 152 rc = -EIO; 153 goto out; 154 } 155 list_add_tail(&new_vlan->list, &smcd->vlan); 156out: 157 spin_unlock_irqrestore(&smcd->lock, flags); 158 return rc; 159} 160 161/* Unregister a VLAN identifier with the ISM device. Use a reference count 162 * and remove a VLAN identifier only when the last DMB using this VLAN is 163 * unregistered. 164 */ 165int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid) 166{ 167 struct smc_ism_vlanid *vlan; 168 unsigned long flags; 169 bool found = false; 170 int rc = 0; 171 172 if (!vlanid) /* No valid vlan id */ 173 return -EINVAL; 174 175 spin_lock_irqsave(&smcd->lock, flags); 176 list_for_each_entry(vlan, &smcd->vlan, list) { 177 if (vlan->vlanid == vlanid) { 178 if (!refcount_dec_and_test(&vlan->refcnt)) 179 goto out; 180 found = true; 181 break; 182 } 183 } 184 if (!found) { 185 rc = -ENOENT; 186 goto out; /* VLAN id not in table */ 187 } 188 189 /* Found and the last reference just gone */ 190 if (smcd->ops->del_vlan_id(smcd, vlanid)) 191 rc = -EIO; 192 list_del(&vlan->list); 193 kfree(vlan); 194out: 195 spin_unlock_irqrestore(&smcd->lock, flags); 196 return rc; 197} 198 199int smc_ism_unregister_dmb(struct smcd_dev *smcd, struct smc_buf_desc *dmb_desc) 200{ 201 struct smcd_dmb dmb; 202 int rc = 0; 203 204 if (!dmb_desc->dma_addr) 205 return rc; 206 207 memset(&dmb, 0, sizeof(dmb)); 208 dmb.dmb_tok = dmb_desc->token; 209 dmb.sba_idx = dmb_desc->sba_idx; 210 dmb.cpu_addr = dmb_desc->cpu_addr; 211 dmb.dma_addr = dmb_desc->dma_addr; 212 dmb.dmb_len = dmb_desc->len; 213 rc = smcd->ops->unregister_dmb(smcd, &dmb); 214 if (!rc || rc == ISM_ERROR) { 215 dmb_desc->cpu_addr = NULL; 216 dmb_desc->dma_addr = 0; 217 } 218 219 return rc; 220} 221 222int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len, 223 struct smc_buf_desc *dmb_desc) 224{ 225#if IS_ENABLED(CONFIG_ISM) 226 struct smcd_dmb dmb; 227 int rc; 228 229 memset(&dmb, 0, sizeof(dmb)); 230 dmb.dmb_len = dmb_len; 231 dmb.sba_idx = dmb_desc->sba_idx; 232 dmb.vlan_id = lgr->vlan_id; 233 dmb.rgid = lgr->peer_gid.gid; 234 rc = lgr->smcd->ops->register_dmb(lgr->smcd, &dmb, &smc_ism_client); 235 if (!rc) { 236 dmb_desc->sba_idx = dmb.sba_idx; 237 dmb_desc->token = dmb.dmb_tok; 238 dmb_desc->cpu_addr = dmb.cpu_addr; 239 dmb_desc->dma_addr = dmb.dma_addr; 240 dmb_desc->len = dmb.dmb_len; 241 } 242 return rc; 243#else 244 return 0; 245#endif 246} 247 248static int smc_nl_handle_smcd_dev(struct smcd_dev *smcd, 249 struct sk_buff *skb, 250 struct netlink_callback *cb) 251{ 252 char smc_pnet[SMC_MAX_PNETID_LEN + 1]; 253 struct smc_pci_dev smc_pci_dev; 254 struct nlattr *port_attrs; 255 struct nlattr *attrs; 256 struct ism_dev *ism; 257 int use_cnt = 0; 258 void *nlh; 259 260 ism = smcd->priv; 261 nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, 262 &smc_gen_nl_family, NLM_F_MULTI, 263 SMC_NETLINK_GET_DEV_SMCD); 264 if (!nlh) 265 goto errmsg; 266 attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCD); 267 if (!attrs) 268 goto errout; 269 use_cnt = atomic_read(&smcd->lgr_cnt); 270 if (nla_put_u32(skb, SMC_NLA_DEV_USE_CNT, use_cnt)) 271 goto errattr; 272 if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, use_cnt > 0)) 273 goto errattr; 274 memset(&smc_pci_dev, 0, sizeof(smc_pci_dev)); 275 smc_set_pci_values(to_pci_dev(ism->dev.parent), &smc_pci_dev); 276 if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev.pci_fid)) 277 goto errattr; 278 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev.pci_pchid)) 279 goto errattr; 280 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev.pci_vendor)) 281 goto errattr; 282 if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev.pci_device)) 283 goto errattr; 284 if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev.pci_id)) 285 goto errattr; 286 287 port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT); 288 if (!port_attrs) 289 goto errattr; 290 if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR, smcd->pnetid_by_user)) 291 goto errportattr; 292 memcpy(smc_pnet, smcd->pnetid, SMC_MAX_PNETID_LEN); 293 smc_pnet[SMC_MAX_PNETID_LEN] = 0; 294 if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet)) 295 goto errportattr; 296 297 nla_nest_end(skb, port_attrs); 298 nla_nest_end(skb, attrs); 299 genlmsg_end(skb, nlh); 300 return 0; 301 302errportattr: 303 nla_nest_cancel(skb, port_attrs); 304errattr: 305 nla_nest_cancel(skb, attrs); 306errout: 307 nlmsg_cancel(skb, nlh); 308errmsg: 309 return -EMSGSIZE; 310} 311 312static void smc_nl_prep_smcd_dev(struct smcd_dev_list *dev_list, 313 struct sk_buff *skb, 314 struct netlink_callback *cb) 315{ 316 struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb); 317 int snum = cb_ctx->pos[0]; 318 struct smcd_dev *smcd; 319 int num = 0; 320 321 mutex_lock(&dev_list->mutex); 322 list_for_each_entry(smcd, &dev_list->list, list) { 323 if (num < snum) 324 goto next; 325 if (smc_nl_handle_smcd_dev(smcd, skb, cb)) 326 goto errout; 327next: 328 num++; 329 } 330errout: 331 mutex_unlock(&dev_list->mutex); 332 cb_ctx->pos[0] = num; 333} 334 335int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb) 336{ 337 smc_nl_prep_smcd_dev(&smcd_dev_list, skb, cb); 338 return skb->len; 339} 340 341#if IS_ENABLED(CONFIG_ISM) 342struct smc_ism_event_work { 343 struct work_struct work; 344 struct smcd_dev *smcd; 345 struct ism_event event; 346}; 347 348#define ISM_EVENT_REQUEST 0x0001 349#define ISM_EVENT_RESPONSE 0x0002 350#define ISM_EVENT_REQUEST_IR 0x00000001 351#define ISM_EVENT_CODE_SHUTDOWN 0x80 352#define ISM_EVENT_CODE_TESTLINK 0x83 353 354union smcd_sw_event_info { 355 u64 info; 356 struct { 357 u8 uid[SMC_LGR_ID_SIZE]; 358 unsigned short vlan_id; 359 u16 code; 360 }; 361}; 362 363static void smcd_handle_sw_event(struct smc_ism_event_work *wrk) 364{ 365 struct smcd_gid peer_gid = { .gid = wrk->event.tok, 366 .gid_ext = 0 }; 367 union smcd_sw_event_info ev_info; 368 369 ev_info.info = wrk->event.info; 370 switch (wrk->event.code) { 371 case ISM_EVENT_CODE_SHUTDOWN: /* Peer shut down DMBs */ 372 smc_smcd_terminate(wrk->smcd, &peer_gid, ev_info.vlan_id); 373 break; 374 case ISM_EVENT_CODE_TESTLINK: /* Activity timer */ 375 if (ev_info.code == ISM_EVENT_REQUEST) { 376 ev_info.code = ISM_EVENT_RESPONSE; 377 wrk->smcd->ops->signal_event(wrk->smcd, 378 &peer_gid, 379 ISM_EVENT_REQUEST_IR, 380 ISM_EVENT_CODE_TESTLINK, 381 ev_info.info); 382 } 383 break; 384 } 385} 386 387/* worker for SMC-D events */ 388static void smc_ism_event_work(struct work_struct *work) 389{ 390 struct smc_ism_event_work *wrk = 391 container_of(work, struct smc_ism_event_work, work); 392 struct smcd_gid smcd_gid = { .gid = wrk->event.tok, 393 .gid_ext = 0 }; 394 395 switch (wrk->event.type) { 396 case ISM_EVENT_GID: /* GID event, token is peer GID */ 397 smc_smcd_terminate(wrk->smcd, &smcd_gid, VLAN_VID_MASK); 398 break; 399 case ISM_EVENT_DMB: 400 break; 401 case ISM_EVENT_SWR: /* Software defined event */ 402 smcd_handle_sw_event(wrk); 403 break; 404 } 405 kfree(wrk); 406} 407 408static struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name, 409 const struct smcd_ops *ops, int max_dmbs) 410{ 411 struct smcd_dev *smcd; 412 413 smcd = devm_kzalloc(parent, sizeof(*smcd), GFP_KERNEL); 414 if (!smcd) 415 return NULL; 416 smcd->conn = devm_kcalloc(parent, max_dmbs, 417 sizeof(struct smc_connection *), GFP_KERNEL); 418 if (!smcd->conn) 419 return NULL; 420 421 smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)", 422 WQ_MEM_RECLAIM, name); 423 if (!smcd->event_wq) 424 return NULL; 425 426 smcd->ops = ops; 427 428 spin_lock_init(&smcd->lock); 429 spin_lock_init(&smcd->lgr_lock); 430 INIT_LIST_HEAD(&smcd->vlan); 431 INIT_LIST_HEAD(&smcd->lgr_list); 432 init_waitqueue_head(&smcd->lgrs_deleted); 433 return smcd; 434} 435 436static void smcd_register_dev(struct ism_dev *ism) 437{ 438 const struct smcd_ops *ops = ism_get_smcd_ops(); 439 struct smcd_dev *smcd; 440 441 if (!ops) 442 return; 443 444 smcd = smcd_alloc_dev(&ism->pdev->dev, dev_name(&ism->pdev->dev), ops, 445 ISM_NR_DMBS); 446 if (!smcd) 447 return; 448 smcd->priv = ism; 449 ism_set_priv(ism, &smc_ism_client, smcd); 450 if (smc_pnetid_by_dev_port(&ism->pdev->dev, 0, smcd->pnetid)) 451 smc_pnetid_by_table_smcd(smcd); 452 453 mutex_lock(&smcd_dev_list.mutex); 454 if (list_empty(&smcd_dev_list.list)) { 455 if (smcd->ops->supports_v2()) 456 smc_ism_v2_capable = true; 457 } 458 /* sort list: devices without pnetid before devices with pnetid */ 459 if (smcd->pnetid[0]) 460 list_add_tail(&smcd->list, &smcd_dev_list.list); 461 else 462 list_add(&smcd->list, &smcd_dev_list.list); 463 mutex_unlock(&smcd_dev_list.mutex); 464 465 pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n", 466 dev_name(&ism->dev), smcd->pnetid, 467 smcd->pnetid_by_user ? " (user defined)" : ""); 468 469 return; 470} 471 472static void smcd_unregister_dev(struct ism_dev *ism) 473{ 474 struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client); 475 476 pr_warn_ratelimited("smc: removing smcd device %s\n", 477 dev_name(&ism->dev)); 478 smcd->going_away = 1; 479 smc_smcd_terminate_all(smcd); 480 mutex_lock(&smcd_dev_list.mutex); 481 list_del_init(&smcd->list); 482 mutex_unlock(&smcd_dev_list.mutex); 483 destroy_workqueue(smcd->event_wq); 484} 485 486/* SMCD Device event handler. Called from ISM device interrupt handler. 487 * Parameters are ism device pointer, 488 * - event->type (0 --> DMB, 1 --> GID), 489 * - event->code (event code), 490 * - event->tok (either DMB token when event type 0, or GID when event type 1) 491 * - event->time (time of day) 492 * - event->info (debug info). 493 * 494 * Context: 495 * - Function called in IRQ context from ISM device driver event handler. 496 */ 497static void smcd_handle_event(struct ism_dev *ism, struct ism_event *event) 498{ 499 struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client); 500 struct smc_ism_event_work *wrk; 501 502 if (smcd->going_away) 503 return; 504 /* copy event to event work queue, and let it be handled there */ 505 wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC); 506 if (!wrk) 507 return; 508 INIT_WORK(&wrk->work, smc_ism_event_work); 509 wrk->smcd = smcd; 510 wrk->event = *event; 511 queue_work(smcd->event_wq, &wrk->work); 512} 513 514/* SMCD Device interrupt handler. Called from ISM device interrupt handler. 515 * Parameters are the ism device pointer, DMB number, and the DMBE bitmask. 516 * Find the connection and schedule the tasklet for this connection. 517 * 518 * Context: 519 * - Function called in IRQ context from ISM device driver IRQ handler. 520 */ 521static void smcd_handle_irq(struct ism_dev *ism, unsigned int dmbno, 522 u16 dmbemask) 523{ 524 struct smcd_dev *smcd = ism_get_priv(ism, &smc_ism_client); 525 struct smc_connection *conn = NULL; 526 unsigned long flags; 527 528 spin_lock_irqsave(&smcd->lock, flags); 529 conn = smcd->conn[dmbno]; 530 if (conn && !conn->killed) 531 tasklet_schedule(&conn->rx_tsklet); 532 spin_unlock_irqrestore(&smcd->lock, flags); 533} 534#endif 535 536int smc_ism_signal_shutdown(struct smc_link_group *lgr) 537{ 538 int rc = 0; 539#if IS_ENABLED(CONFIG_ISM) 540 union smcd_sw_event_info ev_info; 541 542 if (lgr->peer_shutdown) 543 return 0; 544 545 memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE); 546 ev_info.vlan_id = lgr->vlan_id; 547 ev_info.code = ISM_EVENT_REQUEST; 548 rc = lgr->smcd->ops->signal_event(lgr->smcd, &lgr->peer_gid, 549 ISM_EVENT_REQUEST_IR, 550 ISM_EVENT_CODE_SHUTDOWN, 551 ev_info.info); 552#endif 553 return rc; 554} 555 556int smc_ism_init(void) 557{ 558 int rc = 0; 559 560 smc_ism_v2_capable = false; 561 smc_ism_create_system_eid(); 562 563#if IS_ENABLED(CONFIG_ISM) 564 rc = ism_register_client(&smc_ism_client); 565#endif 566 return rc; 567} 568 569void smc_ism_exit(void) 570{ 571#if IS_ENABLED(CONFIG_ISM) 572 ism_unregister_client(&smc_ism_client); 573#endif 574} 575