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_get_disc_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 /* Spec requires dword aligned offsets */ 175 if (offset & 0x3) { 176 status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; 177 goto out; 178 } 179 180 /* 181 * Make sure we're passing at least a buffer of response header size. 182 * If host provided data len is less than the header size, only the 183 * number of bytes requested by host will be sent to host. 184 */ 185 down_read(&nvmet_config_sem); 186 alloc_len = sizeof(*hdr) + entry_size * discovery_log_entries(req); 187 buffer = kzalloc(alloc_len, GFP_KERNEL); 188 if (!buffer) { 189 up_read(&nvmet_config_sem); 190 status = NVME_SC_INTERNAL; 191 goto out; 192 } 193 194 hdr = buffer; 195 list_for_each_entry(p, &req->port->subsystems, entry) { 196 char traddr[NVMF_TRADDR_SIZE]; 197 198 if (!nvmet_host_allowed(p->subsys, ctrl->hostnqn)) 199 continue; 200 201 nvmet_set_disc_traddr(req, req->port, traddr); 202 nvmet_format_discovery_entry(hdr, req->port, 203 p->subsys->subsysnqn, traddr, 204 NVME_NQN_NVME, numrec); 205 numrec++; 206 } 207 208 list_for_each_entry(r, &req->port->referrals, entry) { 209 nvmet_format_discovery_entry(hdr, r, 210 NVME_DISC_SUBSYS_NAME, 211 r->disc_addr.traddr, 212 NVME_NQN_DISC, numrec); 213 numrec++; 214 } 215 216 hdr->genctr = cpu_to_le64(nvmet_genctr); 217 hdr->numrec = cpu_to_le64(numrec); 218 hdr->recfmt = cpu_to_le16(0); 219 220 nvmet_clear_aen_bit(req, NVME_AEN_BIT_DISC_CHANGE); 221 222 up_read(&nvmet_config_sem); 223 224 status = nvmet_copy_to_sgl(req, 0, buffer + offset, data_len); 225 kfree(buffer); 226 out: 227 nvmet_req_complete(req, status); 228 } 229 230 static void nvmet_execute_identify_disc_ctrl(struct nvmet_req *req) 231 { 232 struct nvmet_ctrl *ctrl = req->sq->ctrl; 233 struct nvme_id_ctrl *id; 234 u16 status = 0; 235 236 id = kzalloc(sizeof(*id), GFP_KERNEL); 237 if (!id) { 238 status = NVME_SC_INTERNAL; 239 goto out; 240 } 241 242 memset(id->fr, ' ', sizeof(id->fr)); 243 strncpy((char *)id->fr, UTS_RELEASE, sizeof(id->fr)); 244 245 /* no limit on data transfer sizes for now */ 246 id->mdts = 0; 247 id->cntlid = cpu_to_le16(ctrl->cntlid); 248 id->ver = cpu_to_le32(ctrl->subsys->ver); 249 id->lpa = (1 << 2); 250 251 /* no enforcement soft-limit for maxcmd - pick arbitrary high value */ 252 id->maxcmd = cpu_to_le16(NVMET_MAX_CMD); 253 254 id->sgls = cpu_to_le32(1 << 0); /* we always support SGLs */ 255 if (ctrl->ops->has_keyed_sgls) 256 id->sgls |= cpu_to_le32(1 << 2); 257 if (req->port->inline_data_size) 258 id->sgls |= cpu_to_le32(1 << 20); 259 260 id->oaes = cpu_to_le32(NVMET_DISC_AEN_CFG_OPTIONAL); 261 262 strlcpy(id->subnqn, ctrl->subsys->subsysnqn, sizeof(id->subnqn)); 263 264 status = nvmet_copy_to_sgl(req, 0, id, sizeof(*id)); 265 266 kfree(id); 267 out: 268 nvmet_req_complete(req, status); 269 } 270 271 static void nvmet_execute_disc_set_features(struct nvmet_req *req) 272 { 273 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10); 274 u16 stat; 275 276 switch (cdw10 & 0xff) { 277 case NVME_FEAT_KATO: 278 stat = nvmet_set_feat_kato(req); 279 break; 280 case NVME_FEAT_ASYNC_EVENT: 281 stat = nvmet_set_feat_async_event(req, 282 NVMET_DISC_AEN_CFG_OPTIONAL); 283 break; 284 default: 285 req->error_loc = 286 offsetof(struct nvme_common_command, cdw10); 287 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR; 288 break; 289 } 290 291 nvmet_req_complete(req, stat); 292 } 293 294 static void nvmet_execute_disc_get_features(struct nvmet_req *req) 295 { 296 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10); 297 u16 stat = 0; 298 299 switch (cdw10 & 0xff) { 300 case NVME_FEAT_KATO: 301 nvmet_get_feat_kato(req); 302 break; 303 case NVME_FEAT_ASYNC_EVENT: 304 nvmet_get_feat_async_event(req); 305 break; 306 default: 307 req->error_loc = 308 offsetof(struct nvme_common_command, cdw10); 309 stat = NVME_SC_INVALID_FIELD | NVME_SC_DNR; 310 break; 311 } 312 313 nvmet_req_complete(req, stat); 314 } 315 316 u16 nvmet_parse_discovery_cmd(struct nvmet_req *req) 317 { 318 struct nvme_command *cmd = req->cmd; 319 320 if (unlikely(!(req->sq->ctrl->csts & NVME_CSTS_RDY))) { 321 pr_err("got cmd %d while not ready\n", 322 cmd->common.opcode); 323 req->error_loc = 324 offsetof(struct nvme_common_command, opcode); 325 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 326 } 327 328 switch (cmd->common.opcode) { 329 case nvme_admin_set_features: 330 req->execute = nvmet_execute_disc_set_features; 331 req->data_len = 0; 332 return 0; 333 case nvme_admin_get_features: 334 req->execute = nvmet_execute_disc_get_features; 335 req->data_len = 0; 336 return 0; 337 case nvme_admin_async_event: 338 req->execute = nvmet_execute_async_event; 339 req->data_len = 0; 340 return 0; 341 case nvme_admin_keep_alive: 342 req->execute = nvmet_execute_keep_alive; 343 req->data_len = 0; 344 return 0; 345 case nvme_admin_get_log_page: 346 req->data_len = nvmet_get_log_page_len(cmd); 347 348 switch (cmd->get_log_page.lid) { 349 case NVME_LOG_DISC: 350 req->execute = nvmet_execute_get_disc_log_page; 351 return 0; 352 default: 353 pr_err("unsupported get_log_page lid %d\n", 354 cmd->get_log_page.lid); 355 req->error_loc = 356 offsetof(struct nvme_get_log_page_command, lid); 357 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 358 } 359 case nvme_admin_identify: 360 req->data_len = NVME_IDENTIFY_DATA_SIZE; 361 switch (cmd->identify.cns) { 362 case NVME_ID_CNS_CTRL: 363 req->execute = 364 nvmet_execute_identify_disc_ctrl; 365 return 0; 366 default: 367 pr_err("unsupported identify cns %d\n", 368 cmd->identify.cns); 369 req->error_loc = offsetof(struct nvme_identify, cns); 370 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 371 } 372 default: 373 pr_err("unhandled cmd %d\n", cmd->common.opcode); 374 req->error_loc = offsetof(struct nvme_common_command, opcode); 375 return NVME_SC_INVALID_OPCODE | NVME_SC_DNR; 376 } 377 378 } 379 380 int __init nvmet_init_discovery(void) 381 { 382 nvmet_disc_subsys = 383 nvmet_subsys_alloc(NVME_DISC_SUBSYS_NAME, NVME_NQN_DISC); 384 return PTR_ERR_OR_ZERO(nvmet_disc_subsys); 385 } 386 387 void nvmet_exit_discovery(void) 388 { 389 nvmet_subsys_put(nvmet_disc_subsys); 390 } 391