1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Discovery service for the NVMe over Fabrics target. 4 * Copyright (C) 2016 Intel Corporation. All rights reserved. 5 */ 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 #include <linux/slab.h> 8 #include <generated/utsrelease.h> 9 #include "nvmet.h" 10 11 struct nvmet_subsys *nvmet_disc_subsys; 12 13 static u64 nvmet_genctr; 14 15 static void __nvmet_disc_changed(struct nvmet_port *port, 16 struct nvmet_ctrl *ctrl) 17 { 18 if (ctrl->port != port) 19 return; 20 21 if (nvmet_aen_bit_disabled(ctrl, NVME_AEN_BIT_DISC_CHANGE)) 22 return; 23 24 nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE, 25 NVME_AER_NOTICE_DISC_CHANGED, NVME_LOG_DISC); 26 } 27 28 void nvmet_port_disc_changed(struct nvmet_port *port, 29 struct nvmet_subsys *subsys) 30 { 31 struct nvmet_ctrl *ctrl; 32 33 lockdep_assert_held(&nvmet_config_sem); 34 nvmet_genctr++; 35 36 mutex_lock(&nvmet_disc_subsys->lock); 37 list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) { 38 if (subsys && !nvmet_host_allowed(subsys, ctrl->hostnqn)) 39 continue; 40 41 __nvmet_disc_changed(port, ctrl); 42 } 43 mutex_unlock(&nvmet_disc_subsys->lock); 44 45 /* If transport can signal change, notify transport */ 46 if (port->tr_ops && port->tr_ops->discovery_chg) 47 port->tr_ops->discovery_chg(port); 48 } 49 50 static void __nvmet_subsys_disc_changed(struct nvmet_port *port, 51 struct nvmet_subsys *subsys, 52 struct nvmet_host *host) 53 { 54 struct nvmet_ctrl *ctrl; 55 56 mutex_lock(&nvmet_disc_subsys->lock); 57 list_for_each_entry(ctrl, &nvmet_disc_subsys->ctrls, subsys_entry) { 58 if (host && strcmp(nvmet_host_name(host), ctrl->hostnqn)) 59 continue; 60 61 __nvmet_disc_changed(port, ctrl); 62 } 63 mutex_unlock(&nvmet_disc_subsys->lock); 64 } 65 66 void nvmet_subsys_disc_changed(struct nvmet_subsys *subsys, 67 struct nvmet_host *host) 68 { 69 struct nvmet_port *port; 70 struct nvmet_subsys_link *s; 71 72 nvmet_genctr++; 73 74 list_for_each_entry(port, nvmet_ports, global_entry) 75 list_for_each_entry(s, &port->subsystems, entry) { 76 if (s->subsys != subsys) 77 continue; 78 __nvmet_subsys_disc_changed(port, subsys, host); 79 } 80 } 81 82 void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port) 83 { 84 down_write(&nvmet_config_sem); 85 if (list_empty(&port->entry)) { 86 list_add_tail(&port->entry, &parent->referrals); 87 port->enabled = true; 88 nvmet_port_disc_changed(parent, NULL); 89 } 90 up_write(&nvmet_config_sem); 91 } 92 93 void nvmet_referral_disable(struct nvmet_port *parent, struct nvmet_port *port) 94 { 95 down_write(&nvmet_config_sem); 96 if (!list_empty(&port->entry)) { 97 port->enabled = false; 98 list_del_init(&port->entry); 99 nvmet_port_disc_changed(parent, NULL); 100 } 101 up_write(&nvmet_config_sem); 102 } 103 104 static void nvmet_format_discovery_entry(struct nvmf_disc_rsp_page_hdr *hdr, 105 struct nvmet_port *port, char *subsys_nqn, char *traddr, 106 u8 type, u32 numrec) 107 { 108 struct nvmf_disc_rsp_page_entry *e = &hdr->entries[numrec]; 109 110 e->trtype = port->disc_addr.trtype; 111 e->adrfam = port->disc_addr.adrfam; 112 e->treq = port->disc_addr.treq; 113 e->portid = port->disc_addr.portid; 114 /* we support only dynamic controllers */ 115 e->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC); 116 e->asqsz = cpu_to_le16(NVME_AQ_DEPTH); 117 e->subtype = type; 118 memcpy(e->trsvcid, port->disc_addr.trsvcid, NVMF_TRSVCID_SIZE); 119 memcpy(e->traddr, traddr, NVMF_TRADDR_SIZE); 120 memcpy(e->tsas.common, port->disc_addr.tsas.common, NVMF_TSAS_SIZE); 121 strncpy(e->subnqn, subsys_nqn, NVMF_NQN_SIZE); 122 } 123 124 /* 125 * nvmet_set_disc_traddr - set a correct discovery log entry traddr 126 * 127 * IP based transports (e.g RDMA) can listen on "any" ipv4/ipv6 addresses 128 * (INADDR_ANY or IN6ADDR_ANY_INIT). The discovery log page traddr reply 129 * must not contain that "any" IP address. If the transport implements 130 * .disc_traddr, use it. this callback will set the discovery traddr 131 * from the req->port address in case the port in question listens 132 * "any" IP address. 133 */ 134 static void nvmet_set_disc_traddr(struct nvmet_req *req, struct nvmet_port *port, 135 char *traddr) 136 { 137 if (req->ops->disc_traddr) 138 req->ops->disc_traddr(req, port, traddr); 139 else 140 memcpy(traddr, port->disc_addr.traddr, NVMF_TRADDR_SIZE); 141 } 142 143 static size_t discovery_log_entries(struct nvmet_req *req) 144 { 145 struct nvmet_ctrl *ctrl = req->sq->ctrl; 146 struct nvmet_subsys_link *p; 147 struct nvmet_port *r; 148 size_t entries = 0; 149 150 list_for_each_entry(p, &req->port->subsystems, entry) { 151 if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn)) 152 continue; 153 entries++; 154 } 155 list_for_each_entry(r, &req->port->referrals, entry) 156 entries++; 157 return entries; 158 } 159 160 static void nvmet_execute_disc_get_log_page(struct nvmet_req *req) 161 { 162 const int entry_size = sizeof(struct nvmf_disc_rsp_page_entry); 163 struct nvmet_ctrl *ctrl = req->sq->ctrl; 164 struct nvmf_disc_rsp_page_hdr *hdr; 165 u64 offset = nvmet_get_log_page_offset(req->cmd); 166 size_t data_len = nvmet_get_log_page_len(req->cmd); 167 size_t alloc_len; 168 struct nvmet_subsys_link *p; 169 struct nvmet_port *r; 170 u32 numrec = 0; 171 u16 status = 0; 172 void *buffer; 173 174 if (!nvmet_check_transfer_len(req, data_len)) 175 return; 176 177 if (req->cmd->get_log_page.lid != NVME_LOG_DISC) { 178 req->error_loc = 179 offsetof(struct nvme_get_log_page_command, lid); 180 status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 181 goto out; 182 } 183 184 /* Spec requires dword aligned offsets */ 185 if (offset & 0x3) { 186 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; 187 goto out; 188 } 189 190 /* 191 * Make sure we're passing at least a buffer of response header size. 192 * If host provided data len is less than the header size, only the 193 * number of bytes requested by host will be sent to host. 194 */ 195 down_read(&nvmet_config_sem); 196 alloc_len = sizeof(*hdr) + entry_size * discovery_log_entries(req); 197 buffer = kzalloc(alloc_len, GFP_KERNEL); 198 if (!buffer) { 199 up_read(&nvmet_config_sem); 200 status = NVME_SC_INTERNAL; 201 goto out; 202 } 203 204 hdr = buffer; 205 list_for_each_entry(p, &req->port->subsystems, entry) { 206 char traddr[NVMF_TRADDR_SIZE]; 207 208 if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn)) 209 continue; 210 211 nvmet_set_disc_traddr(req, req->port, traddr); 212 nvmet_format_discovery_entry(hdr, req->port, 213 p->subsys->subsysnqn, traddr, 214 NVME_NQN_NVME, numrec); 215 numrec++; 216 } 217 218 list_for_each_entry(r, &req->port->referrals, entry) { 219 nvmet_format_discovery_entry(hdr, r, 220 NVME_DISC_SUBSYS_NAME, 221 r->disc_addr.traddr, 222 NVME_NQN_DISC, numrec); 223 numrec++; 224 } 225 226 hdr->genctr = cpu_to_le64(nvmet_genctr); 227 hdr->numrec = cpu_to_le64(numrec); 228 hdr->recfmt = cpu_to_le16(0); 229 230 nvmet_clear_aen_bit(req, NVME_AEN_BIT_DISC_CHANGE); 231 232 up_read(&nvmet_config_sem); 233 234 status = nvmet_copy_to_sgl(req, 0, buffer + offset, data_len); 235 kfree(buffer); 236 out: 237 nvmet_req_complete(req, status); 238 } 239 240 static void nvmet_execute_disc_identify(struct nvmet_req *req) 241 { 242 struct nvmet_ctrl *ctrl = req->sq->ctrl; 243 struct nvme_id_ctrl *id; 244 const char model[] = "Linux"; 245 u16 status = 0; 246 247 if (!nvmet_check_transfer_len(req, NVME_IDENTIFY_DATA_SIZE)) 248 return; 249 250 if (req->cmd->identify.cns != NVME_ID_CNS_CTRL) { 251 req->error_loc = offsetof(struct nvme_identify, cns); 252 status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 253 goto out; 254 } 255 256 id = kzalloc(sizeof(*id), GFP_KERNEL); 257 if (!id) { 258 status = NVME_SC_INTERNAL; 259 goto out; 260 } 261 262 memset(id->sn, ' ', sizeof(id->sn)); 263 bin2hex(id->sn, &ctrl->subsys->serial, 264 min(sizeof(ctrl->subsys->serial), sizeof(id->sn) / 2)); 265 memset(id->fr, ' ', sizeof(id->fr)); 266 memcpy_and_pad(id->mn, sizeof(id->mn), model, sizeof(model) - 1, ' '); 267 memcpy_and_pad(id->fr, sizeof(id->fr), 268 UTS_RELEASE, strlen(UTS_RELEASE), ' '); 269 270 /* no limit on data transfer sizes for now */ 271 id->mdts = 0; 272 id->cntlid = cpu_to_le16(ctrl->cntlid); 273 id->ver = cpu_to_le32(ctrl->subsys->ver); 274 id->lpa = (1 << 2); 275 276 /* no enforcement soft-limit for maxcmd - pick arbitrary high value */ 277 id->maxcmd = cpu_to_le16(NVMET_MAX_CMD); 278 279 id->sgls = cpu_to_le32(1 << 0); /* we always support SGLs */ 280 if (ctrl->ops->flags & NVMF_KEYED_SGLS) 281 id->sgls |= cpu_to_le32(1 << 2); 282 if (req->port->inline_data_size) 283 id->sgls |= cpu_to_le32(1 << 20); 284 285 id->oaes = cpu_to_le32(NVMET_DISC_AEN_CFG_OPTIONAL); 286 287 strlcpy(id->subnqn, ctrl->subsys->subsysnqn, sizeof(id->subnqn)); 288 289 status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id)); 290 291 kfree(id); 292 out: 293 nvmet_req_complete(req, status); 294 } 295 296 static void nvmet_execute_disc_set_features(struct nvmet_req *req) 297 { 298 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10); 299 u16 stat; 300 301 if (!nvmet_check_transfer_len(req, 0)) 302 return; 303 304 switch (cdw10 & 0xff) { 305 case NVME_FEAT_KATO: 306 stat = nvmet_set_feat_kato(req); 307 break; 308 case NVME_FEAT_ASYNC_EVENT: 309 stat = nvmet_set_feat_async_event(req, 310 NVMET_DISC_AEN_CFG_OPTIONAL); 311 break; 312 default: 313 req->error_loc = 314 offsetof(struct nvme_common_command, cdw10); 315 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR; 316 break; 317 } 318 319 nvmet_req_complete(req, stat); 320 } 321 322 static void nvmet_execute_disc_get_features(struct nvmet_req *req) 323 { 324 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10); 325 u16 stat = 0; 326 327 if (!nvmet_check_transfer_len(req, 0)) 328 return; 329 330 switch (cdw10 & 0xff) { 331 case NVME_FEAT_KATO: 332 nvmet_get_feat_kato(req); 333 break; 334 case NVME_FEAT_ASYNC_EVENT: 335 nvmet_get_feat_async_event(req); 336 break; 337 default: 338 req->error_loc = 339 offsetof(struct nvme_common_command, cdw10); 340 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR; 341 break; 342 } 343 344 nvmet_req_complete(req, stat); 345 } 346 347 u16 nvmet_parse_discovery_cmd(struct nvmet_req *req) 348 { 349 struct nvme_command *cmd = req->cmd; 350 351 if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) { 352 pr_err("got cmd %d while not ready\n", 353 cmd->common.opcode); 354 req->error_loc = 355 offsetof(struct nvme_common_command, opcode); 356 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 357 } 358 359 switch (cmd->common.opcode) { 360 case nvme_admin_set_features: 361 req->execute = nvmet_execute_disc_set_features; 362 return 0; 363 case nvme_admin_get_features: 364 req->execute = nvmet_execute_disc_get_features; 365 return 0; 366 case nvme_admin_async_event: 367 req->execute = nvmet_execute_async_event; 368 return 0; 369 case nvme_admin_keep_alive: 370 req->execute = nvmet_execute_keep_alive; 371 return 0; 372 case nvme_admin_get_log_page: 373 req->execute = nvmet_execute_disc_get_log_page; 374 return 0; 375 case nvme_admin_identify: 376 req->execute = nvmet_execute_disc_identify; 377 return 0; 378 default: 379 pr_err("unhandled cmd %d\n", cmd->common.opcode); 380 req->error_loc = offsetof(struct nvme_common_command, opcode); 381 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 382 } 383 384 } 385 386 int __init nvmet_init_discovery(void) 387 { 388 nvmet_disc_subsys = 389 nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC); 390 return PTR_ERR_OR_ZERO(nvmet_disc_subsys); 391 } 392 393 void nvmet_exit_discovery(void) 394 { 395 nvmet_subsys_put(nvmet_disc_subsys); 396 } 397