drivers/nvme/target/nvmet.h

   1 /*
   2  * Copyright (c) 2015-2016 HGST, a Western Digital Company.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  */
  13
  14 #ifndef _NVMET_H
  15 #define _NVMET_H
  16
  17 #include <linux/dma-mapping.h>
  18 #include <linux/types.h>
  19 #include <linux/device.h>
  20 #include <linux/kref.h>
  21 #include <linux/percpu-refcount.h>
  22 #include <linux/list.h>
  23 #include <linux/mutex.h>
  24 #include <linux/uuid.h>
  25 #include <linux/nvme.h>
  26 #include <linux/configfs.h>
  27 #include <linux/rcupdate.h>
  28 #include <linux/blkdev.h>
  29 #include <linux/radix-tree.h>
  30
  31 #define NVMET_ASYNC_EVENTS              4
  32 #define NVMET_ERROR_LOG_SLOTS           128
  33 #define NVMET_NO_ERROR_LOC              ((u16)-1)
  34
  35 /*
  36  * Supported optional AENs:
  37  */
  38 #define NVMET_AEN_CFG_OPTIONAL \
  39         (NVME_AEN_CFG_NS_ATTR | NVME_AEN_CFG_ANA_CHANGE)
  40 #define NVMET_DISC_AEN_CFG_OPTIONAL \
  41         (NVME_AEN_CFG_DISC_CHANGE)
  42
  43 /*
  44  * Plus mandatory SMART AENs (we'll never send them, but allow enabling them):
  45  */
  46 #define NVMET_AEN_CFG_ALL \
  47         (NVME_SMART_CRIT_SPARE | NVME_SMART_CRIT_TEMPERATURE | \
  48          NVME_SMART_CRIT_RELIABILITY | NVME_SMART_CRIT_MEDIA | \
  49          NVME_SMART_CRIT_VOLATILE_MEMORY | NVMET_AEN_CFG_OPTIONAL)
  50
  51 /* Helper Macros when NVMe error is NVME_SC_CONNECT_INVALID_PARAM
  52  * The 16 bit shift is to set IATTR bit to 1, which means offending
  53  * offset starts in the data section of connect()
  54  */
  55 #define IPO_IATTR_CONNECT_DATA(x)       \
  56         (cpu_to_le32((1 << 16) | (offsetof(struct nvmf_connect_data, x))))
  57 #define IPO_IATTR_CONNECT_SQE(x)        \
  58         (cpu_to_le32(offsetof(struct nvmf_connect_command, x)))
  59
  60 struct nvmet_ns {
  61         struct list_head        dev_link;
  62         struct percpu_ref       ref;
  63         struct block_device     *bdev;
  64         struct file             *file;
  65         bool                    readonly;
  66         u32                     nsid;
  67         u32                     blksize_shift;
  68         loff_t                  size;
  69         u8                      nguid[16];
  70         uuid_t                  uuid;
  71         u32                     anagrpid;
  72
  73         bool                    buffered_io;
  74         bool                    enabled;
  75         struct nvmet_subsys     *subsys;
  76         const char              *device_path;
  77
  78         struct config_group     device_group;
  79         struct config_group     group;
  80
  81         struct completion       disable_done;
  82         mempool_t               *bvec_pool;
  83         struct kmem_cache       *bvec_cache;
  84
  85         int                     use_p2pmem;
  86         struct pci_dev          *p2p_dev;
  87 };
  88
  89 static inline struct nvmet_ns *to_nvmet_ns(struct config_item *item)
  90 {
  91         return container_of(to_config_group(item), struct nvmet_ns, group);
  92 }
  93
  94 static inline struct device *nvmet_ns_dev(struct nvmet_ns *ns)
  95 {
  96         return ns->bdev ? disk_to_dev(ns->bdev->bd_disk) : NULL;
  97 }
  98
  99 struct nvmet_cq {
 100         u16                     qid;
 101         u16                     size;
 102 };
 103
 104 struct nvmet_sq {
 105         struct nvmet_ctrl       *ctrl;
 106         struct percpu_ref       ref;
 107         u16                     qid;
 108         u16                     size;
 109         u32                     sqhd;
 110         bool                    sqhd_disabled;
 111         struct completion       free_done;
 112         struct completion       confirm_done;
 113 };
 114
 115 struct nvmet_ana_group {
 116         struct config_group     group;
 117         struct nvmet_port       *port;
 118         u32                     grpid;
 119 };
 120
 121 static inline struct nvmet_ana_group *to_ana_group(struct config_item *item)
 122 {
 123         return container_of(to_config_group(item), struct nvmet_ana_group,
 124                         group);
 125 }
 126
 127 /**
 128  * struct nvmet_port -  Common structure to keep port
 129  *                              information for the target.
 130  * @entry:              Entry into referrals or transport list.
 131  * @disc_addr:          Address information is stored in a format defined
 132  *                              for a discovery log page entry.
 133  * @group:              ConfigFS group for this element's folder.
 134  * @priv:               Private data for the transport.
 135  */
 136 struct nvmet_port {
 137         struct list_head                entry;
 138         struct nvmf_disc_rsp_page_entry disc_addr;
 139         struct config_group             group;
 140         struct config_group             subsys_group;
 141         struct list_head                subsystems;
 142         struct config_group             referrals_group;
 143         struct list_head                referrals;
 144         struct list_head                global_entry;
 145         struct config_group             ana_groups_group;
 146         struct nvmet_ana_group          ana_default_group;
 147         enum nvme_ana_state             *ana_state;
 148         void                            *priv;
 149         bool                            enabled;
 150         int                             inline_data_size;
 151 };
 152
 153 static inline struct nvmet_port *to_nvmet_port(struct config_item *item)
 154 {
 155         return container_of(to_config_group(item), struct nvmet_port,
 156                         group);
 157 }
 158
 159 static inline struct nvmet_port *ana_groups_to_port(
 160                 struct config_item *item)
 161 {
 162         return container_of(to_config_group(item), struct nvmet_port,
 163                         ana_groups_group);
 164 }
 165
 166 struct nvmet_ctrl {
 167         struct nvmet_subsys     *subsys;
 168         struct nvmet_cq         **cqs;
 169         struct nvmet_sq         **sqs;
 170
 171         bool                    cmd_seen;
 172
 173         struct mutex            lock;
 174         u64                     cap;
 175         u32                     cc;
 176         u32                     csts;
 177
 178         uuid_t                  hostid;
 179         u16                     cntlid;
 180         u32                     kato;
 181
 182         struct nvmet_port       *port;
 183
 184         u32                     aen_enabled;
 185         unsigned long           aen_masked;
 186         struct nvmet_req        *async_event_cmds[NVMET_ASYNC_EVENTS];
 187         unsigned int            nr_async_event_cmds;
 188         struct list_head        async_events;
 189         struct work_struct      async_event_work;
 190
 191         struct list_head        subsys_entry;
 192         struct kref             ref;
 193         struct delayed_work     ka_work;
 194         struct work_struct      fatal_err_work;
 195
 196         const struct nvmet_fabrics_ops *ops;
 197
 198         __le32                  *changed_ns_list;
 199         u32                     nr_changed_ns;
 200
 201         char                    subsysnqn[NVMF_NQN_FIELD_LEN];
 202         char                    hostnqn[NVMF_NQN_FIELD_LEN];
 203
 204         struct device           *p2p_client;
 205         struct radix_tree_root  p2p_ns_map;
 206
 207         spinlock_t              error_lock;
 208         u64                     err_counter;
 209         struct nvme_error_slot  slots[NVMET_ERROR_LOG_SLOTS];
 210 };
 211
 212 struct nvmet_subsys {
 213         enum nvme_subsys_type   type;
 214
 215         struct mutex            lock;
 216         struct kref             ref;
 217
 218         struct list_head        namespaces;
 219         unsigned int            nr_namespaces;
 220         unsigned int            max_nsid;
 221
 222         struct list_head        ctrls;
 223
 224         struct list_head        hosts;
 225         bool                    allow_any_host;
 226
 227         u16                     max_qid;
 228
 229         u64                     ver;
 230         u64                     serial;
 231         char                    *subsysnqn;
 232
 233         struct config_group     group;
 234
 235         struct config_group     namespaces_group;
 236         struct config_group     allowed_hosts_group;
 237 };
 238
 239 static inline struct nvmet_subsys *to_subsys(struct config_item *item)
 240 {
 241         return container_of(to_config_group(item), struct nvmet_subsys, group);
 242 }
 243
 244 static inline struct nvmet_subsys *namespaces_to_subsys(
 245                 struct config_item *item)
 246 {
 247         return container_of(to_config_group(item), struct nvmet_subsys,
 248                         namespaces_group);
 249 }
 250
 251 struct nvmet_host {
 252         struct config_group     group;
 253 };
 254
 255 static inline struct nvmet_host *to_host(struct config_item *item)
 256 {
 257         return container_of(to_config_group(item), struct nvmet_host, group);
 258 }
 259
 260 static inline char *nvmet_host_name(struct nvmet_host *host)
 261 {
 262         return config_item_name(&host->group.cg_item);
 263 }
 264
 265 struct nvmet_host_link {
 266         struct list_head        entry;
 267         struct nvmet_host       *host;
 268 };
 269
 270 struct nvmet_subsys_link {
 271         struct list_head        entry;
 272         struct nvmet_subsys     *subsys;
 273 };
 274
 275 struct nvmet_req;
 276 struct nvmet_fabrics_ops {
 277         struct module *owner;
 278         unsigned int type;
 279         unsigned int msdbd;
 280         bool has_keyed_sgls : 1;
 281         void (*queue_response)(struct nvmet_req *req);
 282         int (*add_port)(struct nvmet_port *port);
 283         void (*remove_port)(struct nvmet_port *port);
 284         void (*delete_ctrl)(struct nvmet_ctrl *ctrl);
 285         void (*disc_traddr)(struct nvmet_req *req,
 286                         struct nvmet_port *port, char *traddr);
 287         u16 (*install_queue)(struct nvmet_sq *nvme_sq);
 288 };
 289
 290 #define NVMET_MAX_INLINE_BIOVEC 8
 291 #define NVMET_MAX_INLINE_DATA_LEN NVMET_MAX_INLINE_BIOVEC * PAGE_SIZE
 292
 293 struct nvmet_req {
 294         struct nvme_command     *cmd;
 295         struct nvme_completion  *rsp;
 296         struct nvmet_sq         *sq;
 297         struct nvmet_cq         *cq;
 298         struct nvmet_ns         *ns;
 299         struct scatterlist      *sg;
 300         struct bio_vec          inline_bvec[NVMET_MAX_INLINE_BIOVEC];
 301         union {
 302                 struct {
 303                         struct bio      inline_bio;
 304                 } b;
 305                 struct {
 306                         bool                    mpool_alloc;
 307                         struct kiocb            iocb;
 308                         struct bio_vec          *bvec;
 309                         struct work_struct      work;
 310                 } f;
 311         };
 312         int                     sg_cnt;
 313         /* data length as parsed from the command: */
 314         size_t                  data_len;
 315         /* data length as parsed from the SGL descriptor: */
 316         size_t                  transfer_len;
 317
 318         struct nvmet_port       *port;
 319
 320         void (*execute)(struct nvmet_req *req);
 321         const struct nvmet_fabrics_ops *ops;
 322
 323         struct pci_dev          *p2p_dev;
 324         struct device           *p2p_client;
 325         u16                     error_loc;
 326         u64                     error_slba;
 327 };
 328
 329 extern struct workqueue_struct *buffered_io_wq;
 330
 331 static inline void nvmet_set_result(struct nvmet_req *req, u32 result)
 332 {
 333         req->rsp->result.u32 = cpu_to_le32(result);
 334 }
 335
 336 /*
 337  * NVMe command writes actually are DMA reads for us on the target side.
 338  */
 339 static inline enum dma_data_direction
 340 nvmet_data_dir(struct nvmet_req *req)
 341 {
 342         return nvme_is_write(req->cmd) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
 343 }
 344
 345 struct nvmet_async_event {
 346         struct list_head        entry;
 347         u8                      event_type;
 348         u8                      event_info;
 349         u8                      log_page;
 350 };
 351
 352 static inline void nvmet_clear_aen_bit(struct nvmet_req *req, u32 bn)
 353 {
 354         int rae = le32_to_cpu(req->cmd->common.cdw10) & 1 << 15;
 355
 356         if (!rae)
 357                 clear_bit(bn, &req->sq->ctrl->aen_masked);
 358 }
 359
 360 static inline bool nvmet_aen_bit_disabled(struct nvmet_ctrl *ctrl, u32 bn)
 361 {
 362         if (!(READ_ONCE(ctrl->aen_enabled) & (1 << bn)))
 363                 return true;
 364         return test_and_set_bit(bn, &ctrl->aen_masked);
 365 }
 366
 367 void nvmet_get_feat_kato(struct nvmet_req *req);
 368 void nvmet_get_feat_async_event(struct nvmet_req *req);
 369 u16 nvmet_set_feat_kato(struct nvmet_req *req);
 370 u16 nvmet_set_feat_async_event(struct nvmet_req *req, u32 mask);
 371 void nvmet_execute_async_event(struct nvmet_req *req);
 372
 373 u16 nvmet_parse_connect_cmd(struct nvmet_req *req);
 374 u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req);
 375 u16 nvmet_file_parse_io_cmd(struct nvmet_req *req);
 376 u16 nvmet_parse_admin_cmd(struct nvmet_req *req);
 377 u16 nvmet_parse_discovery_cmd(struct nvmet_req *req);
 378 u16 nvmet_parse_fabrics_cmd(struct nvmet_req *req);
 379
 380 bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
 381                 struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops);
 382 void nvmet_req_uninit(struct nvmet_req *req);
 383 void nvmet_req_execute(struct nvmet_req *req);
 384 void nvmet_req_complete(struct nvmet_req *req, u16 status);
 385 int nvmet_req_alloc_sgl(struct nvmet_req *req);
 386 void nvmet_req_free_sgl(struct nvmet_req *req);
 387
 388 void nvmet_execute_keep_alive(struct nvmet_req *req);
 389
 390 void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq, u16 qid,
 391                 u16 size);
 392 void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq, u16 qid,
 393                 u16 size);
 394 void nvmet_sq_destroy(struct nvmet_sq *sq);
 395 int nvmet_sq_init(struct nvmet_sq *sq);
 396
 397 void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl);
 398
 399 void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new);
 400 u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
 401                 struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp);
 402 u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid,
 403                 struct nvmet_req *req, struct nvmet_ctrl **ret);
 404 void nvmet_ctrl_put(struct nvmet_ctrl *ctrl);
 405 u16 nvmet_check_ctrl_status(struct nvmet_req *req, struct nvme_command *cmd);
 406
 407 struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
 408                 enum nvme_subsys_type type);
 409 void nvmet_subsys_put(struct nvmet_subsys *subsys);
 410 void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys);
 411
 412 struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid);
 413 void nvmet_put_namespace(struct nvmet_ns *ns);
 414 int nvmet_ns_enable(struct nvmet_ns *ns);
 415 void nvmet_ns_disable(struct nvmet_ns *ns);
 416 struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid);
 417 void nvmet_ns_free(struct nvmet_ns *ns);
 418
 419 void nvmet_send_ana_event(struct nvmet_subsys *subsys,
 420                 struct nvmet_port *port);
 421 void nvmet_port_send_ana_event(struct nvmet_port *port);
 422
 423 int nvmet_register_transport(const struct nvmet_fabrics_ops *ops);
 424 void nvmet_unregister_transport(const struct nvmet_fabrics_ops *ops);
 425
 426 int nvmet_enable_port(struct nvmet_port *port);
 427 void nvmet_disable_port(struct nvmet_port *port);
 428
 429 void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port);
 430 void nvmet_referral_disable(struct nvmet_port *parent, struct nvmet_port *port);
 431
 432 u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
 433                 size_t len);
 434 u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf,
 435                 size_t len);
 436 u16 nvmet_zero_sgl(struct nvmet_req *req, off_t off, size_t len);
 437
 438 u32 nvmet_get_log_page_len(struct nvme_command *cmd);
 439
 440 extern struct list_head *nvmet_ports;
 441 void nvmet_port_disc_changed(struct nvmet_port *port,
 442                 struct nvmet_subsys *subsys);
 443 void nvmet_subsys_disc_changed(struct nvmet_subsys *subsys,
 444                 struct nvmet_host *host);
 445 void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type,
 446                 u8 event_info, u8 log_page);
 447
 448 #define NVMET_QUEUE_SIZE        1024
 449 #define NVMET_NR_QUEUES         128
 450 #define NVMET_MAX_CMD           NVMET_QUEUE_SIZE
 451
 452 /*
 453  * Nice round number that makes a list of nsids fit into a page.
 454  * Should become tunable at some point in the future.
 455  */
 456 #define NVMET_MAX_NAMESPACES    1024
 457
 458 /*
 459  * 0 is not a valid ANA group ID, so we start numbering at 1.
 460  *
 461  * ANA Group 1 exists without manual intervention, has namespaces assigned to it
 462  * by default, and is available in an optimized state through all ports.
 463  */
 464 #define NVMET_MAX_ANAGRPS       128
 465 #define NVMET_DEFAULT_ANA_GRPID 1
 466
 467 #define NVMET_KAS               10
 468 #define NVMET_DISC_KATO_MS              120000
 469
 470 int __init nvmet_init_configfs(void);
 471 void __exit nvmet_exit_configfs(void);
 472
 473 int __init nvmet_init_discovery(void);
 474 void nvmet_exit_discovery(void);
 475
 476 extern struct nvmet_subsys *nvmet_disc_subsys;
 477 extern struct rw_semaphore nvmet_config_sem;
 478
 479 extern u32 nvmet_ana_group_enabled[NVMET_MAX_ANAGRPS + 1];
 480 extern u64 nvmet_ana_chgcnt;
 481 extern struct rw_semaphore nvmet_ana_sem;
 482
 483 bool nvmet_host_allowed(struct nvmet_subsys *subsys, const char *hostnqn);
 484
 485 int nvmet_bdev_ns_enable(struct nvmet_ns *ns);
 486 int nvmet_file_ns_enable(struct nvmet_ns *ns);
 487 void nvmet_bdev_ns_disable(struct nvmet_ns *ns);
 488 void nvmet_file_ns_disable(struct nvmet_ns *ns);
 489 u16 nvmet_bdev_flush(struct nvmet_req *req);
 490 u16 nvmet_file_flush(struct nvmet_req *req);
 491 void nvmet_ns_changed(struct nvmet_subsys *subsys, u32 nsid);
 492
 493 static inline u32 nvmet_rw_len(struct nvmet_req *req)
 494 {
 495         return ((u32)le16_to_cpu(req->cmd->rw.length) + 1) <<
 496                         req->ns->blksize_shift;
 497 }
 498
 499 u16 errno_to_nvme_status(struct nvmet_req *req, int errno);
 500 #endif /* _NVMET_H */