Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Common code for the NVMe target. |
| 3 | * Copyright (c) 2015-2016 HGST, a Western Digital Company. |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify it |
| 6 | * under the terms and conditions of the GNU General Public License, |
| 7 | * version 2, as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope it will be useful, but WITHOUT |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 12 | * more details. |
| 13 | */ |
| 14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 15 | #include <linux/module.h> |
Sagi Grimberg | 28b8911 | 2016-08-04 11:18:49 +0300 | [diff] [blame] | 16 | #include <linux/random.h> |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 17 | #include "nvmet.h" |
| 18 | |
| 19 | static struct nvmet_fabrics_ops *nvmet_transports[NVMF_TRTYPE_MAX]; |
| 20 | |
| 21 | /* |
| 22 | * This read/write semaphore is used to synchronize access to configuration |
| 23 | * information on a target system that will result in discovery log page |
| 24 | * information change for at least one host. |
| 25 | * The full list of resources to protected by this semaphore is: |
| 26 | * |
| 27 | * - subsystems list |
| 28 | * - per-subsystem allowed hosts list |
| 29 | * - allow_any_host subsystem attribute |
| 30 | * - nvmet_genctr |
| 31 | * - the nvmet_transports array |
| 32 | * |
| 33 | * When updating any of those lists/structures write lock should be obtained, |
| 34 | * while when reading (popolating discovery log page or checking host-subsystem |
| 35 | * link) read lock is obtained to allow concurrent reads. |
| 36 | */ |
| 37 | DECLARE_RWSEM(nvmet_config_sem); |
| 38 | |
| 39 | static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port, |
| 40 | const char *subsysnqn); |
| 41 | |
| 42 | u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf, |
| 43 | size_t len) |
| 44 | { |
| 45 | if (sg_pcopy_from_buffer(req->sg, req->sg_cnt, buf, len, off) != len) |
| 46 | return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR; |
| 47 | return 0; |
| 48 | } |
| 49 | |
| 50 | u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf, size_t len) |
| 51 | { |
| 52 | if (sg_pcopy_to_buffer(req->sg, req->sg_cnt, buf, len, off) != len) |
| 53 | return NVME_SC_SGL_INVALID_DATA | NVME_SC_DNR; |
| 54 | return 0; |
| 55 | } |
| 56 | |
| 57 | static u32 nvmet_async_event_result(struct nvmet_async_event *aen) |
| 58 | { |
| 59 | return aen->event_type | (aen->event_info << 8) | (aen->log_page << 16); |
| 60 | } |
| 61 | |
| 62 | static void nvmet_async_events_free(struct nvmet_ctrl *ctrl) |
| 63 | { |
| 64 | struct nvmet_req *req; |
| 65 | |
| 66 | while (1) { |
| 67 | mutex_lock(&ctrl->lock); |
| 68 | if (!ctrl->nr_async_event_cmds) { |
| 69 | mutex_unlock(&ctrl->lock); |
| 70 | return; |
| 71 | } |
| 72 | |
| 73 | req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds]; |
| 74 | mutex_unlock(&ctrl->lock); |
| 75 | nvmet_req_complete(req, NVME_SC_INTERNAL | NVME_SC_DNR); |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | static void nvmet_async_event_work(struct work_struct *work) |
| 80 | { |
| 81 | struct nvmet_ctrl *ctrl = |
| 82 | container_of(work, struct nvmet_ctrl, async_event_work); |
| 83 | struct nvmet_async_event *aen; |
| 84 | struct nvmet_req *req; |
| 85 | |
| 86 | while (1) { |
| 87 | mutex_lock(&ctrl->lock); |
| 88 | aen = list_first_entry_or_null(&ctrl->async_events, |
| 89 | struct nvmet_async_event, entry); |
| 90 | if (!aen || !ctrl->nr_async_event_cmds) { |
| 91 | mutex_unlock(&ctrl->lock); |
| 92 | return; |
| 93 | } |
| 94 | |
| 95 | req = ctrl->async_event_cmds[--ctrl->nr_async_event_cmds]; |
| 96 | nvmet_set_result(req, nvmet_async_event_result(aen)); |
| 97 | |
| 98 | list_del(&aen->entry); |
| 99 | kfree(aen); |
| 100 | |
| 101 | mutex_unlock(&ctrl->lock); |
| 102 | nvmet_req_complete(req, 0); |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | static void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type, |
| 107 | u8 event_info, u8 log_page) |
| 108 | { |
| 109 | struct nvmet_async_event *aen; |
| 110 | |
| 111 | aen = kmalloc(sizeof(*aen), GFP_KERNEL); |
| 112 | if (!aen) |
| 113 | return; |
| 114 | |
| 115 | aen->event_type = event_type; |
| 116 | aen->event_info = event_info; |
| 117 | aen->log_page = log_page; |
| 118 | |
| 119 | mutex_lock(&ctrl->lock); |
| 120 | list_add_tail(&aen->entry, &ctrl->async_events); |
| 121 | mutex_unlock(&ctrl->lock); |
| 122 | |
| 123 | schedule_work(&ctrl->async_event_work); |
| 124 | } |
| 125 | |
| 126 | int nvmet_register_transport(struct nvmet_fabrics_ops *ops) |
| 127 | { |
| 128 | int ret = 0; |
| 129 | |
| 130 | down_write(&nvmet_config_sem); |
| 131 | if (nvmet_transports[ops->type]) |
| 132 | ret = -EINVAL; |
| 133 | else |
| 134 | nvmet_transports[ops->type] = ops; |
| 135 | up_write(&nvmet_config_sem); |
| 136 | |
| 137 | return ret; |
| 138 | } |
| 139 | EXPORT_SYMBOL_GPL(nvmet_register_transport); |
| 140 | |
| 141 | void nvmet_unregister_transport(struct nvmet_fabrics_ops *ops) |
| 142 | { |
| 143 | down_write(&nvmet_config_sem); |
| 144 | nvmet_transports[ops->type] = NULL; |
| 145 | up_write(&nvmet_config_sem); |
| 146 | } |
| 147 | EXPORT_SYMBOL_GPL(nvmet_unregister_transport); |
| 148 | |
| 149 | int nvmet_enable_port(struct nvmet_port *port) |
| 150 | { |
| 151 | struct nvmet_fabrics_ops *ops; |
| 152 | int ret; |
| 153 | |
| 154 | lockdep_assert_held(&nvmet_config_sem); |
| 155 | |
| 156 | ops = nvmet_transports[port->disc_addr.trtype]; |
| 157 | if (!ops) { |
| 158 | up_write(&nvmet_config_sem); |
| 159 | request_module("nvmet-transport-%d", port->disc_addr.trtype); |
| 160 | down_write(&nvmet_config_sem); |
| 161 | ops = nvmet_transports[port->disc_addr.trtype]; |
| 162 | if (!ops) { |
| 163 | pr_err("transport type %d not supported\n", |
| 164 | port->disc_addr.trtype); |
| 165 | return -EINVAL; |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | if (!try_module_get(ops->owner)) |
| 170 | return -EINVAL; |
| 171 | |
| 172 | ret = ops->add_port(port); |
| 173 | if (ret) { |
| 174 | module_put(ops->owner); |
| 175 | return ret; |
| 176 | } |
| 177 | |
| 178 | port->enabled = true; |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | void nvmet_disable_port(struct nvmet_port *port) |
| 183 | { |
| 184 | struct nvmet_fabrics_ops *ops; |
| 185 | |
| 186 | lockdep_assert_held(&nvmet_config_sem); |
| 187 | |
| 188 | port->enabled = false; |
| 189 | |
| 190 | ops = nvmet_transports[port->disc_addr.trtype]; |
| 191 | ops->remove_port(port); |
| 192 | module_put(ops->owner); |
| 193 | } |
| 194 | |
| 195 | static void nvmet_keep_alive_timer(struct work_struct *work) |
| 196 | { |
| 197 | struct nvmet_ctrl *ctrl = container_of(to_delayed_work(work), |
| 198 | struct nvmet_ctrl, ka_work); |
| 199 | |
| 200 | pr_err("ctrl %d keep-alive timer (%d seconds) expired!\n", |
| 201 | ctrl->cntlid, ctrl->kato); |
| 202 | |
| 203 | ctrl->ops->delete_ctrl(ctrl); |
| 204 | } |
| 205 | |
| 206 | static void nvmet_start_keep_alive_timer(struct nvmet_ctrl *ctrl) |
| 207 | { |
| 208 | pr_debug("ctrl %d start keep-alive timer for %d secs\n", |
| 209 | ctrl->cntlid, ctrl->kato); |
| 210 | |
| 211 | INIT_DELAYED_WORK(&ctrl->ka_work, nvmet_keep_alive_timer); |
| 212 | schedule_delayed_work(&ctrl->ka_work, ctrl->kato * HZ); |
| 213 | } |
| 214 | |
| 215 | static void nvmet_stop_keep_alive_timer(struct nvmet_ctrl *ctrl) |
| 216 | { |
| 217 | pr_debug("ctrl %d stop keep-alive\n", ctrl->cntlid); |
| 218 | |
| 219 | cancel_delayed_work_sync(&ctrl->ka_work); |
| 220 | } |
| 221 | |
| 222 | static struct nvmet_ns *__nvmet_find_namespace(struct nvmet_ctrl *ctrl, |
| 223 | __le32 nsid) |
| 224 | { |
| 225 | struct nvmet_ns *ns; |
| 226 | |
| 227 | list_for_each_entry_rcu(ns, &ctrl->subsys->namespaces, dev_link) { |
| 228 | if (ns->nsid == le32_to_cpu(nsid)) |
| 229 | return ns; |
| 230 | } |
| 231 | |
| 232 | return NULL; |
| 233 | } |
| 234 | |
| 235 | struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid) |
| 236 | { |
| 237 | struct nvmet_ns *ns; |
| 238 | |
| 239 | rcu_read_lock(); |
| 240 | ns = __nvmet_find_namespace(ctrl, nsid); |
| 241 | if (ns) |
| 242 | percpu_ref_get(&ns->ref); |
| 243 | rcu_read_unlock(); |
| 244 | |
| 245 | return ns; |
| 246 | } |
| 247 | |
| 248 | static void nvmet_destroy_namespace(struct percpu_ref *ref) |
| 249 | { |
| 250 | struct nvmet_ns *ns = container_of(ref, struct nvmet_ns, ref); |
| 251 | |
| 252 | complete(&ns->disable_done); |
| 253 | } |
| 254 | |
| 255 | void nvmet_put_namespace(struct nvmet_ns *ns) |
| 256 | { |
| 257 | percpu_ref_put(&ns->ref); |
| 258 | } |
| 259 | |
| 260 | int nvmet_ns_enable(struct nvmet_ns *ns) |
| 261 | { |
| 262 | struct nvmet_subsys *subsys = ns->subsys; |
| 263 | struct nvmet_ctrl *ctrl; |
| 264 | int ret = 0; |
| 265 | |
| 266 | mutex_lock(&subsys->lock); |
Solganik Alexander | fe3d462 | 2016-10-30 10:35:15 +0200 | [diff] [blame] | 267 | if (ns->enabled) |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 268 | goto out_unlock; |
| 269 | |
| 270 | ns->bdev = blkdev_get_by_path(ns->device_path, FMODE_READ | FMODE_WRITE, |
| 271 | NULL); |
| 272 | if (IS_ERR(ns->bdev)) { |
| 273 | pr_err("nvmet: failed to open block device %s: (%ld)\n", |
| 274 | ns->device_path, PTR_ERR(ns->bdev)); |
| 275 | ret = PTR_ERR(ns->bdev); |
| 276 | ns->bdev = NULL; |
| 277 | goto out_unlock; |
| 278 | } |
| 279 | |
| 280 | ns->size = i_size_read(ns->bdev->bd_inode); |
| 281 | ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev)); |
| 282 | |
| 283 | ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace, |
| 284 | 0, GFP_KERNEL); |
| 285 | if (ret) |
| 286 | goto out_blkdev_put; |
| 287 | |
| 288 | if (ns->nsid > subsys->max_nsid) |
| 289 | subsys->max_nsid = ns->nsid; |
| 290 | |
| 291 | /* |
| 292 | * The namespaces list needs to be sorted to simplify the implementation |
| 293 | * of the Identify Namepace List subcommand. |
| 294 | */ |
| 295 | if (list_empty(&subsys->namespaces)) { |
| 296 | list_add_tail_rcu(&ns->dev_link, &subsys->namespaces); |
| 297 | } else { |
| 298 | struct nvmet_ns *old; |
| 299 | |
| 300 | list_for_each_entry_rcu(old, &subsys->namespaces, dev_link) { |
| 301 | BUG_ON(ns->nsid == old->nsid); |
| 302 | if (ns->nsid < old->nsid) |
| 303 | break; |
| 304 | } |
| 305 | |
| 306 | list_add_tail_rcu(&ns->dev_link, &old->dev_link); |
| 307 | } |
| 308 | |
| 309 | list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) |
| 310 | nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE, 0, 0); |
| 311 | |
Solganik Alexander | fe3d462 | 2016-10-30 10:35:15 +0200 | [diff] [blame] | 312 | ns->enabled = true; |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 313 | ret = 0; |
| 314 | out_unlock: |
| 315 | mutex_unlock(&subsys->lock); |
| 316 | return ret; |
| 317 | out_blkdev_put: |
| 318 | blkdev_put(ns->bdev, FMODE_WRITE|FMODE_READ); |
| 319 | ns->bdev = NULL; |
| 320 | goto out_unlock; |
| 321 | } |
| 322 | |
| 323 | void nvmet_ns_disable(struct nvmet_ns *ns) |
| 324 | { |
| 325 | struct nvmet_subsys *subsys = ns->subsys; |
| 326 | struct nvmet_ctrl *ctrl; |
| 327 | |
| 328 | mutex_lock(&subsys->lock); |
Solganik Alexander | fe3d462 | 2016-10-30 10:35:15 +0200 | [diff] [blame] | 329 | if (!ns->enabled) |
| 330 | goto out_unlock; |
| 331 | |
| 332 | ns->enabled = false; |
| 333 | list_del_rcu(&ns->dev_link); |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 334 | mutex_unlock(&subsys->lock); |
| 335 | |
| 336 | /* |
| 337 | * Now that we removed the namespaces from the lookup list, we |
| 338 | * can kill the per_cpu ref and wait for any remaining references |
| 339 | * to be dropped, as well as a RCU grace period for anyone only |
| 340 | * using the namepace under rcu_read_lock(). Note that we can't |
| 341 | * use call_rcu here as we need to ensure the namespaces have |
| 342 | * been fully destroyed before unloading the module. |
| 343 | */ |
| 344 | percpu_ref_kill(&ns->ref); |
| 345 | synchronize_rcu(); |
| 346 | wait_for_completion(&ns->disable_done); |
| 347 | percpu_ref_exit(&ns->ref); |
| 348 | |
| 349 | mutex_lock(&subsys->lock); |
| 350 | list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) |
| 351 | nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE, 0, 0); |
| 352 | |
| 353 | if (ns->bdev) |
| 354 | blkdev_put(ns->bdev, FMODE_WRITE|FMODE_READ); |
Solganik Alexander | fe3d462 | 2016-10-30 10:35:15 +0200 | [diff] [blame] | 355 | out_unlock: |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 356 | mutex_unlock(&subsys->lock); |
| 357 | } |
| 358 | |
| 359 | void nvmet_ns_free(struct nvmet_ns *ns) |
| 360 | { |
| 361 | nvmet_ns_disable(ns); |
| 362 | |
| 363 | kfree(ns->device_path); |
| 364 | kfree(ns); |
| 365 | } |
| 366 | |
| 367 | struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid) |
| 368 | { |
| 369 | struct nvmet_ns *ns; |
| 370 | |
| 371 | ns = kzalloc(sizeof(*ns), GFP_KERNEL); |
| 372 | if (!ns) |
| 373 | return NULL; |
| 374 | |
| 375 | INIT_LIST_HEAD(&ns->dev_link); |
| 376 | init_completion(&ns->disable_done); |
| 377 | |
| 378 | ns->nsid = nsid; |
| 379 | ns->subsys = subsys; |
| 380 | |
| 381 | return ns; |
| 382 | } |
| 383 | |
| 384 | static void __nvmet_req_complete(struct nvmet_req *req, u16 status) |
| 385 | { |
| 386 | if (status) |
| 387 | nvmet_set_status(req, status); |
| 388 | |
| 389 | /* XXX: need to fill in something useful for sq_head */ |
| 390 | req->rsp->sq_head = 0; |
| 391 | if (likely(req->sq)) /* may happen during early failure */ |
| 392 | req->rsp->sq_id = cpu_to_le16(req->sq->qid); |
| 393 | req->rsp->command_id = req->cmd->common.command_id; |
| 394 | |
| 395 | if (req->ns) |
| 396 | nvmet_put_namespace(req->ns); |
| 397 | req->ops->queue_response(req); |
| 398 | } |
| 399 | |
| 400 | void nvmet_req_complete(struct nvmet_req *req, u16 status) |
| 401 | { |
| 402 | __nvmet_req_complete(req, status); |
| 403 | percpu_ref_put(&req->sq->ref); |
| 404 | } |
| 405 | EXPORT_SYMBOL_GPL(nvmet_req_complete); |
| 406 | |
| 407 | void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq, |
| 408 | u16 qid, u16 size) |
| 409 | { |
| 410 | cq->qid = qid; |
| 411 | cq->size = size; |
| 412 | |
| 413 | ctrl->cqs[qid] = cq; |
| 414 | } |
| 415 | |
| 416 | void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq, |
| 417 | u16 qid, u16 size) |
| 418 | { |
| 419 | sq->qid = qid; |
| 420 | sq->size = size; |
| 421 | |
| 422 | ctrl->sqs[qid] = sq; |
| 423 | } |
| 424 | |
| 425 | void nvmet_sq_destroy(struct nvmet_sq *sq) |
| 426 | { |
| 427 | /* |
| 428 | * If this is the admin queue, complete all AERs so that our |
| 429 | * queue doesn't have outstanding requests on it. |
| 430 | */ |
| 431 | if (sq->ctrl && sq->ctrl->sqs && sq->ctrl->sqs[0] == sq) |
| 432 | nvmet_async_events_free(sq->ctrl); |
| 433 | percpu_ref_kill(&sq->ref); |
| 434 | wait_for_completion(&sq->free_done); |
| 435 | percpu_ref_exit(&sq->ref); |
| 436 | |
| 437 | if (sq->ctrl) { |
| 438 | nvmet_ctrl_put(sq->ctrl); |
| 439 | sq->ctrl = NULL; /* allows reusing the queue later */ |
| 440 | } |
| 441 | } |
| 442 | EXPORT_SYMBOL_GPL(nvmet_sq_destroy); |
| 443 | |
| 444 | static void nvmet_sq_free(struct percpu_ref *ref) |
| 445 | { |
| 446 | struct nvmet_sq *sq = container_of(ref, struct nvmet_sq, ref); |
| 447 | |
| 448 | complete(&sq->free_done); |
| 449 | } |
| 450 | |
| 451 | int nvmet_sq_init(struct nvmet_sq *sq) |
| 452 | { |
| 453 | int ret; |
| 454 | |
| 455 | ret = percpu_ref_init(&sq->ref, nvmet_sq_free, 0, GFP_KERNEL); |
| 456 | if (ret) { |
| 457 | pr_err("percpu_ref init failed!\n"); |
| 458 | return ret; |
| 459 | } |
| 460 | init_completion(&sq->free_done); |
| 461 | |
| 462 | return 0; |
| 463 | } |
| 464 | EXPORT_SYMBOL_GPL(nvmet_sq_init); |
| 465 | |
| 466 | bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq, |
| 467 | struct nvmet_sq *sq, struct nvmet_fabrics_ops *ops) |
| 468 | { |
| 469 | u8 flags = req->cmd->common.flags; |
| 470 | u16 status; |
| 471 | |
| 472 | req->cq = cq; |
| 473 | req->sq = sq; |
| 474 | req->ops = ops; |
| 475 | req->sg = NULL; |
| 476 | req->sg_cnt = 0; |
| 477 | req->rsp->status = 0; |
| 478 | |
| 479 | /* no support for fused commands yet */ |
| 480 | if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) { |
| 481 | status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; |
| 482 | goto fail; |
| 483 | } |
| 484 | |
| 485 | /* either variant of SGLs is fine, as we don't support metadata */ |
| 486 | if (unlikely((flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METABUF && |
| 487 | (flags & NVME_CMD_SGL_ALL) != NVME_CMD_SGL_METASEG)) { |
| 488 | status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; |
| 489 | goto fail; |
| 490 | } |
| 491 | |
| 492 | if (unlikely(!req->sq->ctrl)) |
| 493 | /* will return an error for any Non-connect command: */ |
| 494 | status = nvmet_parse_connect_cmd(req); |
| 495 | else if (likely(req->sq->qid != 0)) |
| 496 | status = nvmet_parse_io_cmd(req); |
| 497 | else if (req->cmd->common.opcode == nvme_fabrics_command) |
| 498 | status = nvmet_parse_fabrics_cmd(req); |
| 499 | else if (req->sq->ctrl->subsys->type == NVME_NQN_DISC) |
| 500 | status = nvmet_parse_discovery_cmd(req); |
| 501 | else |
| 502 | status = nvmet_parse_admin_cmd(req); |
| 503 | |
| 504 | if (status) |
| 505 | goto fail; |
| 506 | |
| 507 | if (unlikely(!percpu_ref_tryget_live(&sq->ref))) { |
| 508 | status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; |
| 509 | goto fail; |
| 510 | } |
| 511 | |
| 512 | return true; |
| 513 | |
| 514 | fail: |
| 515 | __nvmet_req_complete(req, status); |
| 516 | return false; |
| 517 | } |
| 518 | EXPORT_SYMBOL_GPL(nvmet_req_init); |
| 519 | |
| 520 | static inline bool nvmet_cc_en(u32 cc) |
| 521 | { |
| 522 | return cc & 0x1; |
| 523 | } |
| 524 | |
| 525 | static inline u8 nvmet_cc_css(u32 cc) |
| 526 | { |
| 527 | return (cc >> 4) & 0x7; |
| 528 | } |
| 529 | |
| 530 | static inline u8 nvmet_cc_mps(u32 cc) |
| 531 | { |
| 532 | return (cc >> 7) & 0xf; |
| 533 | } |
| 534 | |
| 535 | static inline u8 nvmet_cc_ams(u32 cc) |
| 536 | { |
| 537 | return (cc >> 11) & 0x7; |
| 538 | } |
| 539 | |
| 540 | static inline u8 nvmet_cc_shn(u32 cc) |
| 541 | { |
| 542 | return (cc >> 14) & 0x3; |
| 543 | } |
| 544 | |
| 545 | static inline u8 nvmet_cc_iosqes(u32 cc) |
| 546 | { |
| 547 | return (cc >> 16) & 0xf; |
| 548 | } |
| 549 | |
| 550 | static inline u8 nvmet_cc_iocqes(u32 cc) |
| 551 | { |
| 552 | return (cc >> 20) & 0xf; |
| 553 | } |
| 554 | |
| 555 | static void nvmet_start_ctrl(struct nvmet_ctrl *ctrl) |
| 556 | { |
| 557 | lockdep_assert_held(&ctrl->lock); |
| 558 | |
| 559 | if (nvmet_cc_iosqes(ctrl->cc) != NVME_NVM_IOSQES || |
| 560 | nvmet_cc_iocqes(ctrl->cc) != NVME_NVM_IOCQES || |
| 561 | nvmet_cc_mps(ctrl->cc) != 0 || |
| 562 | nvmet_cc_ams(ctrl->cc) != 0 || |
| 563 | nvmet_cc_css(ctrl->cc) != 0) { |
| 564 | ctrl->csts = NVME_CSTS_CFS; |
| 565 | return; |
| 566 | } |
| 567 | |
| 568 | ctrl->csts = NVME_CSTS_RDY; |
| 569 | } |
| 570 | |
| 571 | static void nvmet_clear_ctrl(struct nvmet_ctrl *ctrl) |
| 572 | { |
| 573 | lockdep_assert_held(&ctrl->lock); |
| 574 | |
| 575 | /* XXX: tear down queues? */ |
| 576 | ctrl->csts &= ~NVME_CSTS_RDY; |
| 577 | ctrl->cc = 0; |
| 578 | } |
| 579 | |
| 580 | void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new) |
| 581 | { |
| 582 | u32 old; |
| 583 | |
| 584 | mutex_lock(&ctrl->lock); |
| 585 | old = ctrl->cc; |
| 586 | ctrl->cc = new; |
| 587 | |
| 588 | if (nvmet_cc_en(new) && !nvmet_cc_en(old)) |
| 589 | nvmet_start_ctrl(ctrl); |
| 590 | if (!nvmet_cc_en(new) && nvmet_cc_en(old)) |
| 591 | nvmet_clear_ctrl(ctrl); |
| 592 | if (nvmet_cc_shn(new) && !nvmet_cc_shn(old)) { |
| 593 | nvmet_clear_ctrl(ctrl); |
| 594 | ctrl->csts |= NVME_CSTS_SHST_CMPLT; |
| 595 | } |
| 596 | if (!nvmet_cc_shn(new) && nvmet_cc_shn(old)) |
| 597 | ctrl->csts &= ~NVME_CSTS_SHST_CMPLT; |
| 598 | mutex_unlock(&ctrl->lock); |
| 599 | } |
| 600 | |
| 601 | static void nvmet_init_cap(struct nvmet_ctrl *ctrl) |
| 602 | { |
| 603 | /* command sets supported: NVMe command set: */ |
| 604 | ctrl->cap = (1ULL << 37); |
| 605 | /* CC.EN timeout in 500msec units: */ |
| 606 | ctrl->cap |= (15ULL << 24); |
| 607 | /* maximum queue entries supported: */ |
| 608 | ctrl->cap |= NVMET_QUEUE_SIZE - 1; |
| 609 | } |
| 610 | |
| 611 | u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid, |
| 612 | struct nvmet_req *req, struct nvmet_ctrl **ret) |
| 613 | { |
| 614 | struct nvmet_subsys *subsys; |
| 615 | struct nvmet_ctrl *ctrl; |
| 616 | u16 status = 0; |
| 617 | |
| 618 | subsys = nvmet_find_get_subsys(req->port, subsysnqn); |
| 619 | if (!subsys) { |
| 620 | pr_warn("connect request for invalid subsystem %s!\n", |
| 621 | subsysnqn); |
| 622 | req->rsp->result = IPO_IATTR_CONNECT_DATA(subsysnqn); |
| 623 | return NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; |
| 624 | } |
| 625 | |
| 626 | mutex_lock(&subsys->lock); |
| 627 | list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) { |
| 628 | if (ctrl->cntlid == cntlid) { |
| 629 | if (strncmp(hostnqn, ctrl->hostnqn, NVMF_NQN_SIZE)) { |
| 630 | pr_warn("hostnqn mismatch.\n"); |
| 631 | continue; |
| 632 | } |
| 633 | if (!kref_get_unless_zero(&ctrl->ref)) |
| 634 | continue; |
| 635 | |
| 636 | *ret = ctrl; |
| 637 | goto out; |
| 638 | } |
| 639 | } |
| 640 | |
| 641 | pr_warn("could not find controller %d for subsys %s / host %s\n", |
| 642 | cntlid, subsysnqn, hostnqn); |
| 643 | req->rsp->result = IPO_IATTR_CONNECT_DATA(cntlid); |
| 644 | status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; |
| 645 | |
| 646 | out: |
| 647 | mutex_unlock(&subsys->lock); |
| 648 | nvmet_subsys_put(subsys); |
| 649 | return status; |
| 650 | } |
| 651 | |
| 652 | static bool __nvmet_host_allowed(struct nvmet_subsys *subsys, |
| 653 | const char *hostnqn) |
| 654 | { |
| 655 | struct nvmet_host_link *p; |
| 656 | |
| 657 | if (subsys->allow_any_host) |
| 658 | return true; |
| 659 | |
| 660 | list_for_each_entry(p, &subsys->hosts, entry) { |
| 661 | if (!strcmp(nvmet_host_name(p->host), hostnqn)) |
| 662 | return true; |
| 663 | } |
| 664 | |
| 665 | return false; |
| 666 | } |
| 667 | |
| 668 | static bool nvmet_host_discovery_allowed(struct nvmet_req *req, |
| 669 | const char *hostnqn) |
| 670 | { |
| 671 | struct nvmet_subsys_link *s; |
| 672 | |
| 673 | list_for_each_entry(s, &req->port->subsystems, entry) { |
| 674 | if (__nvmet_host_allowed(s->subsys, hostnqn)) |
| 675 | return true; |
| 676 | } |
| 677 | |
| 678 | return false; |
| 679 | } |
| 680 | |
| 681 | bool nvmet_host_allowed(struct nvmet_req *req, struct nvmet_subsys *subsys, |
| 682 | const char *hostnqn) |
| 683 | { |
| 684 | lockdep_assert_held(&nvmet_config_sem); |
| 685 | |
| 686 | if (subsys->type == NVME_NQN_DISC) |
| 687 | return nvmet_host_discovery_allowed(req, hostnqn); |
| 688 | else |
| 689 | return __nvmet_host_allowed(subsys, hostnqn); |
| 690 | } |
| 691 | |
| 692 | u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, |
| 693 | struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp) |
| 694 | { |
| 695 | struct nvmet_subsys *subsys; |
| 696 | struct nvmet_ctrl *ctrl; |
| 697 | int ret; |
| 698 | u16 status; |
| 699 | |
| 700 | status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; |
| 701 | subsys = nvmet_find_get_subsys(req->port, subsysnqn); |
| 702 | if (!subsys) { |
| 703 | pr_warn("connect request for invalid subsystem %s!\n", |
| 704 | subsysnqn); |
| 705 | req->rsp->result = IPO_IATTR_CONNECT_DATA(subsysnqn); |
| 706 | goto out; |
| 707 | } |
| 708 | |
| 709 | status = NVME_SC_CONNECT_INVALID_PARAM | NVME_SC_DNR; |
| 710 | down_read(&nvmet_config_sem); |
| 711 | if (!nvmet_host_allowed(req, subsys, hostnqn)) { |
| 712 | pr_info("connect by host %s for subsystem %s not allowed\n", |
| 713 | hostnqn, subsysnqn); |
| 714 | req->rsp->result = IPO_IATTR_CONNECT_DATA(hostnqn); |
| 715 | up_read(&nvmet_config_sem); |
| 716 | goto out_put_subsystem; |
| 717 | } |
| 718 | up_read(&nvmet_config_sem); |
| 719 | |
| 720 | status = NVME_SC_INTERNAL; |
| 721 | ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); |
| 722 | if (!ctrl) |
| 723 | goto out_put_subsystem; |
| 724 | mutex_init(&ctrl->lock); |
| 725 | |
| 726 | nvmet_init_cap(ctrl); |
| 727 | |
| 728 | INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work); |
| 729 | INIT_LIST_HEAD(&ctrl->async_events); |
| 730 | |
| 731 | memcpy(ctrl->subsysnqn, subsysnqn, NVMF_NQN_SIZE); |
| 732 | memcpy(ctrl->hostnqn, hostnqn, NVMF_NQN_SIZE); |
| 733 | |
Sagi Grimberg | 28b8911 | 2016-08-04 11:18:49 +0300 | [diff] [blame] | 734 | /* generate a random serial number as our controllers are ephemeral: */ |
| 735 | get_random_bytes(&ctrl->serial, sizeof(ctrl->serial)); |
| 736 | |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 737 | kref_init(&ctrl->ref); |
| 738 | ctrl->subsys = subsys; |
| 739 | |
| 740 | ctrl->cqs = kcalloc(subsys->max_qid + 1, |
| 741 | sizeof(struct nvmet_cq *), |
| 742 | GFP_KERNEL); |
| 743 | if (!ctrl->cqs) |
| 744 | goto out_free_ctrl; |
| 745 | |
| 746 | ctrl->sqs = kcalloc(subsys->max_qid + 1, |
| 747 | sizeof(struct nvmet_sq *), |
| 748 | GFP_KERNEL); |
| 749 | if (!ctrl->sqs) |
| 750 | goto out_free_cqs; |
| 751 | |
| 752 | ret = ida_simple_get(&subsys->cntlid_ida, |
| 753 | NVME_CNTLID_MIN, NVME_CNTLID_MAX, |
| 754 | GFP_KERNEL); |
| 755 | if (ret < 0) { |
| 756 | status = NVME_SC_CONNECT_CTRL_BUSY | NVME_SC_DNR; |
| 757 | goto out_free_sqs; |
| 758 | } |
| 759 | ctrl->cntlid = ret; |
| 760 | |
| 761 | ctrl->ops = req->ops; |
| 762 | if (ctrl->subsys->type == NVME_NQN_DISC) { |
| 763 | /* Don't accept keep-alive timeout for discovery controllers */ |
| 764 | if (kato) { |
| 765 | status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; |
| 766 | goto out_free_sqs; |
| 767 | } |
| 768 | |
| 769 | /* |
| 770 | * Discovery controllers use some arbitrary high value in order |
| 771 | * to cleanup stale discovery sessions |
| 772 | * |
| 773 | * From the latest base diff RC: |
| 774 | * "The Keep Alive command is not supported by |
| 775 | * Discovery controllers. A transport may specify a |
| 776 | * fixed Discovery controller activity timeout value |
| 777 | * (e.g., 2 minutes). If no commands are received |
| 778 | * by a Discovery controller within that time |
| 779 | * period, the controller may perform the |
| 780 | * actions for Keep Alive Timer expiration". |
| 781 | */ |
| 782 | ctrl->kato = NVMET_DISC_KATO; |
| 783 | } else { |
| 784 | /* keep-alive timeout in seconds */ |
| 785 | ctrl->kato = DIV_ROUND_UP(kato, 1000); |
| 786 | } |
| 787 | nvmet_start_keep_alive_timer(ctrl); |
| 788 | |
| 789 | mutex_lock(&subsys->lock); |
| 790 | list_add_tail(&ctrl->subsys_entry, &subsys->ctrls); |
| 791 | mutex_unlock(&subsys->lock); |
| 792 | |
| 793 | *ctrlp = ctrl; |
| 794 | return 0; |
| 795 | |
| 796 | out_free_sqs: |
| 797 | kfree(ctrl->sqs); |
| 798 | out_free_cqs: |
| 799 | kfree(ctrl->cqs); |
| 800 | out_free_ctrl: |
| 801 | kfree(ctrl); |
| 802 | out_put_subsystem: |
| 803 | nvmet_subsys_put(subsys); |
| 804 | out: |
| 805 | return status; |
| 806 | } |
| 807 | |
| 808 | static void nvmet_ctrl_free(struct kref *ref) |
| 809 | { |
| 810 | struct nvmet_ctrl *ctrl = container_of(ref, struct nvmet_ctrl, ref); |
| 811 | struct nvmet_subsys *subsys = ctrl->subsys; |
| 812 | |
| 813 | nvmet_stop_keep_alive_timer(ctrl); |
| 814 | |
| 815 | mutex_lock(&subsys->lock); |
| 816 | list_del(&ctrl->subsys_entry); |
| 817 | mutex_unlock(&subsys->lock); |
| 818 | |
| 819 | ida_simple_remove(&subsys->cntlid_ida, ctrl->cntlid); |
| 820 | nvmet_subsys_put(subsys); |
| 821 | |
| 822 | kfree(ctrl->sqs); |
| 823 | kfree(ctrl->cqs); |
| 824 | kfree(ctrl); |
| 825 | } |
| 826 | |
| 827 | void nvmet_ctrl_put(struct nvmet_ctrl *ctrl) |
| 828 | { |
| 829 | kref_put(&ctrl->ref, nvmet_ctrl_free); |
| 830 | } |
| 831 | |
| 832 | static void nvmet_fatal_error_handler(struct work_struct *work) |
| 833 | { |
| 834 | struct nvmet_ctrl *ctrl = |
| 835 | container_of(work, struct nvmet_ctrl, fatal_err_work); |
| 836 | |
| 837 | pr_err("ctrl %d fatal error occurred!\n", ctrl->cntlid); |
| 838 | ctrl->ops->delete_ctrl(ctrl); |
| 839 | } |
| 840 | |
| 841 | void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl) |
| 842 | { |
Sagi Grimberg | 8242dda | 2016-11-06 11:03:30 +0200 | [diff] [blame] | 843 | mutex_lock(&ctrl->lock); |
| 844 | if (!(ctrl->csts & NVME_CSTS_CFS)) { |
| 845 | ctrl->csts |= NVME_CSTS_CFS; |
| 846 | INIT_WORK(&ctrl->fatal_err_work, nvmet_fatal_error_handler); |
| 847 | schedule_work(&ctrl->fatal_err_work); |
| 848 | } |
| 849 | mutex_unlock(&ctrl->lock); |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 850 | } |
| 851 | EXPORT_SYMBOL_GPL(nvmet_ctrl_fatal_error); |
| 852 | |
| 853 | static struct nvmet_subsys *nvmet_find_get_subsys(struct nvmet_port *port, |
| 854 | const char *subsysnqn) |
| 855 | { |
| 856 | struct nvmet_subsys_link *p; |
| 857 | |
| 858 | if (!port) |
| 859 | return NULL; |
| 860 | |
| 861 | if (!strncmp(NVME_DISC_SUBSYS_NAME, subsysnqn, |
| 862 | NVMF_NQN_SIZE)) { |
| 863 | if (!kref_get_unless_zero(&nvmet_disc_subsys->ref)) |
| 864 | return NULL; |
| 865 | return nvmet_disc_subsys; |
| 866 | } |
| 867 | |
| 868 | down_read(&nvmet_config_sem); |
| 869 | list_for_each_entry(p, &port->subsystems, entry) { |
| 870 | if (!strncmp(p->subsys->subsysnqn, subsysnqn, |
| 871 | NVMF_NQN_SIZE)) { |
| 872 | if (!kref_get_unless_zero(&p->subsys->ref)) |
| 873 | break; |
| 874 | up_read(&nvmet_config_sem); |
| 875 | return p->subsys; |
| 876 | } |
| 877 | } |
| 878 | up_read(&nvmet_config_sem); |
| 879 | return NULL; |
| 880 | } |
| 881 | |
| 882 | struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn, |
| 883 | enum nvme_subsys_type type) |
| 884 | { |
| 885 | struct nvmet_subsys *subsys; |
| 886 | |
| 887 | subsys = kzalloc(sizeof(*subsys), GFP_KERNEL); |
| 888 | if (!subsys) |
| 889 | return NULL; |
| 890 | |
Gabriel Krisman Bertazi | 8ef2074 | 2016-10-19 09:51:05 -0600 | [diff] [blame] | 891 | subsys->ver = NVME_VS(1, 2, 1); /* NVMe 1.2.1 */ |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 892 | |
| 893 | switch (type) { |
| 894 | case NVME_NQN_NVME: |
| 895 | subsys->max_qid = NVMET_NR_QUEUES; |
| 896 | break; |
| 897 | case NVME_NQN_DISC: |
| 898 | subsys->max_qid = 0; |
| 899 | break; |
| 900 | default: |
| 901 | pr_err("%s: Unknown Subsystem type - %d\n", __func__, type); |
| 902 | kfree(subsys); |
| 903 | return NULL; |
| 904 | } |
| 905 | subsys->type = type; |
| 906 | subsys->subsysnqn = kstrndup(subsysnqn, NVMF_NQN_SIZE, |
| 907 | GFP_KERNEL); |
Wei Yongjun | 69555af | 2016-07-06 12:02:09 +0000 | [diff] [blame] | 908 | if (!subsys->subsysnqn) { |
Christoph Hellwig | a07b497 | 2016-06-21 18:04:20 +0200 | [diff] [blame] | 909 | kfree(subsys); |
| 910 | return NULL; |
| 911 | } |
| 912 | |
| 913 | kref_init(&subsys->ref); |
| 914 | |
| 915 | mutex_init(&subsys->lock); |
| 916 | INIT_LIST_HEAD(&subsys->namespaces); |
| 917 | INIT_LIST_HEAD(&subsys->ctrls); |
| 918 | |
| 919 | ida_init(&subsys->cntlid_ida); |
| 920 | |
| 921 | INIT_LIST_HEAD(&subsys->hosts); |
| 922 | |
| 923 | return subsys; |
| 924 | } |
| 925 | |
| 926 | static void nvmet_subsys_free(struct kref *ref) |
| 927 | { |
| 928 | struct nvmet_subsys *subsys = |
| 929 | container_of(ref, struct nvmet_subsys, ref); |
| 930 | |
| 931 | WARN_ON_ONCE(!list_empty(&subsys->namespaces)); |
| 932 | |
| 933 | ida_destroy(&subsys->cntlid_ida); |
| 934 | kfree(subsys->subsysnqn); |
| 935 | kfree(subsys); |
| 936 | } |
| 937 | |
| 938 | void nvmet_subsys_put(struct nvmet_subsys *subsys) |
| 939 | { |
| 940 | kref_put(&subsys->ref, nvmet_subsys_free); |
| 941 | } |
| 942 | |
| 943 | static int __init nvmet_init(void) |
| 944 | { |
| 945 | int error; |
| 946 | |
| 947 | error = nvmet_init_discovery(); |
| 948 | if (error) |
| 949 | goto out; |
| 950 | |
| 951 | error = nvmet_init_configfs(); |
| 952 | if (error) |
| 953 | goto out_exit_discovery; |
| 954 | return 0; |
| 955 | |
| 956 | out_exit_discovery: |
| 957 | nvmet_exit_discovery(); |
| 958 | out: |
| 959 | return error; |
| 960 | } |
| 961 | |
| 962 | static void __exit nvmet_exit(void) |
| 963 | { |
| 964 | nvmet_exit_configfs(); |
| 965 | nvmet_exit_discovery(); |
| 966 | |
| 967 | BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_entry) != 1024); |
| 968 | BUILD_BUG_ON(sizeof(struct nvmf_disc_rsp_page_hdr) != 1024); |
| 969 | } |
| 970 | |
| 971 | module_init(nvmet_init); |
| 972 | module_exit(nvmet_exit); |
| 973 | |
| 974 | MODULE_LICENSE("GPL v2"); |