drivers/nvme/target/discovery.c

   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 }