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