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/nvme.h>
  25 #include <linux/configfs.h>
  26 #include <linux/rcupdate.h>
  27 #include <linux/blkdev.h>
  28
  29 #define NVMET_ASYNC_EVENTS              4
  30 #define NVMET_ERROR_LOG_SLOTS           128
  31
  32 /* Helper Macros when NVMe error is NVME_SC_CONNECT_INVALID_PARAM
  33  * The 16 bit shift is to set IATTR bit to 1, which means offending
  34  * offset starts in the data section of connect()
  35  */
  36 #define IPO_IATTR_CONNECT_DATA(x)       \
  37         (cpu_to_le32((1 << 16) | (offsetof(struct nvmf_connect_data, x))))
  38 #define IPO_IATTR_CONNECT_SQE(x)        \
  39         (cpu_to_le32(offsetof(struct nvmf_connect_command, x)))
  40
  41 struct nvmet_ns {
  42         struct list_head        dev_link;
  43         struct percpu_ref       ref;
  44         struct block_device     *bdev;
  45         u32                     nsid;
  46         u32                     blksize_shift;
  47         loff_t                  size;
  48         u8                      nguid[16];
  49
  50         bool                    enabled;
  51         struct nvmet_subsys     *subsys;
  52         const char              *device_path;
  53
  54         struct config_group     device_group;
  55         struct config_group     group;
  56
  57         struct completion       disable_done;
  58 };
  59
  60 static inline struct nvmet_ns *to_nvmet_ns(struct config_item *item)
  61 {
  62         return container_of(to_config_group(item), struct nvmet_ns, group);
  63 }
  64
  65 struct nvmet_cq {
  66         u16                     qid;
  67         u16                     size;
  68 };
  69
  70 struct nvmet_sq {
  71         struct nvmet_ctrl       *ctrl;
  72         struct percpu_ref       ref;
  73         u16                     qid;
  74         u16                     size;
  75         struct completion       free_done;
  76         struct completion       confirm_done;
  77 };
  78
  79 /**
  80  * struct nvmet_port -  Common structure to keep port
  81  *                              information for the target.
  82  * @entry:              List head for holding a list of these elements.
  83  * @disc_addr:          Address information is stored in a format defined
  84  *                              for a discovery log page entry.
  85  * @group:              ConfigFS group for this element's folder.
  86  * @priv:               Private data for the transport.
  87  */
  88 struct nvmet_port {
  89         struct list_head                entry;
  90         struct nvmf_disc_rsp_page_entry disc_addr;
  91         struct config_group             group;
  92         struct config_group             subsys_group;
  93         struct list_head                subsystems;
  94         struct config_group             referrals_group;
  95         struct list_head                referrals;
  96         void                            *priv;
  97         bool                            enabled;
  98 };
  99
 100 static inline struct nvmet_port *to_nvmet_port(struct config_item *item)
 101 {
 102         return container_of(to_config_group(item), struct nvmet_port,
 103                         group);
 104 }
 105
 106 struct nvmet_ctrl {
 107         struct nvmet_subsys     *subsys;
 108         struct nvmet_cq         **cqs;
 109         struct nvmet_sq         **sqs;
 110
 111         struct mutex            lock;
 112         u64                     cap;
 113         u64                     serial;
 114         u32                     cc;
 115         u32                     csts;
 116
 117         u16                     cntlid;
 118         u32                     kato;
 119
 120         struct nvmet_req        *async_event_cmds[NVMET_ASYNC_EVENTS];
 121         unsigned int            nr_async_event_cmds;
 122         struct list_head        async_events;
 123         struct work_struct      async_event_work;
 124
 125         struct list_head        subsys_entry;
 126         struct kref             ref;
 127         struct delayed_work     ka_work;
 128         struct work_struct      fatal_err_work;
 129
 130         struct nvmet_fabrics_ops *ops;
 131
 132         char                    subsysnqn[NVMF_NQN_FIELD_LEN];
 133         char                    hostnqn[NVMF_NQN_FIELD_LEN];
 134 };
 135
 136 struct nvmet_subsys {
 137         enum nvme_subsys_type   type;
 138
 139         struct mutex            lock;
 140         struct kref             ref;
 141
 142         struct list_head        namespaces;
 143         unsigned int            max_nsid;
 144
 145         struct list_head        ctrls;
 146
 147         struct list_head        hosts;
 148         bool                    allow_any_host;
 149
 150         u16                     max_qid;
 151
 152         u64                     ver;
 153         char                    *subsysnqn;
 154
 155         struct config_group     group;
 156
 157         struct config_group     namespaces_group;
 158         struct config_group     allowed_hosts_group;
 159 };
 160
 161 static inline struct nvmet_subsys *to_subsys(struct config_item *item)
 162 {
 163         return container_of(to_config_group(item), struct nvmet_subsys, group);
 164 }
 165
 166 static inline struct nvmet_subsys *namespaces_to_subsys(
 167                 struct config_item *item)
 168 {
 169         return container_of(to_config_group(item), struct nvmet_subsys,
 170                         namespaces_group);
 171 }
 172
 173 struct nvmet_host {
 174         struct config_group     group;
 175 };
 176
 177 static inline struct nvmet_host *to_host(struct config_item *item)
 178 {
 179         return container_of(to_config_group(item), struct nvmet_host, group);
 180 }
 181
 182 static inline char *nvmet_host_name(struct nvmet_host *host)
 183 {
 184         return config_item_name(&host->group.cg_item);
 185 }
 186
 187 struct nvmet_host_link {
 188         struct list_head        entry;
 189         struct nvmet_host       *host;
 190 };
 191
 192 struct nvmet_subsys_link {
 193         struct list_head        entry;
 194         struct nvmet_subsys     *subsys;
 195 };
 196
 197 struct nvmet_req;
 198 struct nvmet_fabrics_ops {
 199         struct module *owner;
 200         unsigned int type;
 201         unsigned int sqe_inline_size;
 202         unsigned int msdbd;
 203         bool has_keyed_sgls : 1;
 204         void (*queue_response)(struct nvmet_req *req);
 205         int (*add_port)(struct nvmet_port *port);
 206         void (*remove_port)(struct nvmet_port *port);
 207         void (*delete_ctrl)(struct nvmet_ctrl *ctrl);
 208 };
 209
 210 #define NVMET_MAX_INLINE_BIOVEC 8
 211
 212 struct nvmet_req {
 213         struct nvme_command     *cmd;
 214         struct nvme_completion  *rsp;
 215         struct nvmet_sq         *sq;
 216         struct nvmet_cq         *cq;
 217         struct nvmet_ns         *ns;
 218         struct scatterlist      *sg;
 219         struct bio              inline_bio;
 220         struct bio_vec          inline_bvec[NVMET_MAX_INLINE_BIOVEC];
 221         int                     sg_cnt;
 222         size_t                  data_len;
 223
 224         struct nvmet_port       *port;
 225
 226         void (*execute)(struct nvmet_req *req);
 227         struct nvmet_fabrics_ops *ops;
 228 };
 229
 230 static inline void nvmet_set_status(struct nvmet_req *req, u16 status)
 231 {
 232         req->rsp->status = cpu_to_le16(status << 1);
 233 }
 234
 235 static inline void nvmet_set_result(struct nvmet_req *req, u32 result)
 236 {
 237         req->rsp->result.u32 = cpu_to_le32(result);
 238 }
 239
 240 /*
 241  * NVMe command writes actually are DMA reads for us on the target side.
 242  */
 243 static inline enum dma_data_direction
 244 nvmet_data_dir(struct nvmet_req *req)
 245 {
 246         return nvme_is_write(req->cmd) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
 247 }
 248
 249 struct nvmet_async_event {
 250         struct list_head        entry;
 251         u8                      event_type;
 252         u8                      event_info;
 253         u8                      log_page;
 254 };
 255
 256 u16 nvmet_parse_connect_cmd(struct nvmet_req *req);
 257 u16 nvmet_parse_io_cmd(struct nvmet_req *req);
 258 u16 nvmet_parse_admin_cmd(struct nvmet_req *req);
 259 u16 nvmet_parse_discovery_cmd(struct nvmet_req *req);
 260 u16 nvmet_parse_fabrics_cmd(struct nvmet_req *req);
 261
 262 bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
 263                 struct nvmet_sq *sq, struct nvmet_fabrics_ops *ops);
 264 void nvmet_req_uninit(struct nvmet_req *req);
 265 void nvmet_req_complete(struct nvmet_req *req, u16 status);
 266
 267 void nvmet_cq_setup(struct nvmet_ctrl *ctrl, struct nvmet_cq *cq, u16 qid,
 268                 u16 size);
 269 void nvmet_sq_setup(struct nvmet_ctrl *ctrl, struct nvmet_sq *sq, u16 qid,
 270                 u16 size);
 271 void nvmet_sq_destroy(struct nvmet_sq *sq);
 272 int nvmet_sq_init(struct nvmet_sq *sq);
 273
 274 void nvmet_ctrl_fatal_error(struct nvmet_ctrl *ctrl);
 275
 276 void nvmet_update_cc(struct nvmet_ctrl *ctrl, u32 new);
 277 u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
 278                 struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp);
 279 u16 nvmet_ctrl_find_get(const char *subsysnqn, const char *hostnqn, u16 cntlid,
 280                 struct nvmet_req *req, struct nvmet_ctrl **ret);
 281 void nvmet_ctrl_put(struct nvmet_ctrl *ctrl);
 282 u16 nvmet_check_ctrl_status(struct nvmet_req *req, struct nvme_command *cmd);
 283
 284 struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
 285                 enum nvme_subsys_type type);
 286 void nvmet_subsys_put(struct nvmet_subsys *subsys);
 287 void nvmet_subsys_del_ctrls(struct nvmet_subsys *subsys);
 288
 289 struct nvmet_ns *nvmet_find_namespace(struct nvmet_ctrl *ctrl, __le32 nsid);
 290 void nvmet_put_namespace(struct nvmet_ns *ns);
 291 int nvmet_ns_enable(struct nvmet_ns *ns);
 292 void nvmet_ns_disable(struct nvmet_ns *ns);
 293 struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid);
 294 void nvmet_ns_free(struct nvmet_ns *ns);
 295
 296 int nvmet_register_transport(struct nvmet_fabrics_ops *ops);
 297 void nvmet_unregister_transport(struct nvmet_fabrics_ops *ops);
 298
 299 int nvmet_enable_port(struct nvmet_port *port);
 300 void nvmet_disable_port(struct nvmet_port *port);
 301
 302 void nvmet_referral_enable(struct nvmet_port *parent, struct nvmet_port *port);
 303 void nvmet_referral_disable(struct nvmet_port *port);
 304
 305 u16 nvmet_copy_to_sgl(struct nvmet_req *req, off_t off, const void *buf,
 306                 size_t len);
 307 u16 nvmet_copy_from_sgl(struct nvmet_req *req, off_t off, void *buf,
 308                 size_t len);
 309
 310 u32 nvmet_get_log_page_len(struct nvme_command *cmd);
 311
 312 #define NVMET_QUEUE_SIZE        1024
 313 #define NVMET_NR_QUEUES         64
 314 #define NVMET_MAX_CMD           NVMET_QUEUE_SIZE
 315 #define NVMET_KAS               10
 316 #define NVMET_DISC_KATO         120
 317
 318 int __init nvmet_init_configfs(void);
 319 void __exit nvmet_exit_configfs(void);
 320
 321 int __init nvmet_init_discovery(void);
 322 void nvmet_exit_discovery(void);
 323
 324 extern struct nvmet_subsys *nvmet_disc_subsys;
 325 extern u64 nvmet_genctr;
 326 extern struct rw_semaphore nvmet_config_sem;
 327
 328 bool nvmet_host_allowed(struct nvmet_req *req, struct nvmet_subsys *subsys,
 329                 const char *hostnqn);
 330
 331 #endif /* _NVMET_H */