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