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