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