drivers/nvme/host/nvme.h

   1 /*
   2  * Copyright (c) 2011-2014, Intel Corporation.
   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 _NVME_H
  15 #define _NVME_H
  16
  17 #include <linux/nvme.h>
  18 #include <linux/pci.h>
  19 #include <linux/kref.h>
  20 #include <linux/blk-mq.h>
  21 #include <linux/lightnvm.h>
  22
  23 enum {
  24         /*
  25          * Driver internal status code for commands that were cancelled due
  26          * to timeouts or controller shutdown.  The value is negative so
  27          * that it a) doesn't overlap with the unsigned hardware error codes,
  28          * and b) can easily be tested for.
  29          */
  30         NVME_SC_CANCELLED               = -EINTR,
  31 };
  32
  33 extern unsigned char nvme_io_timeout;
  34 #define NVME_IO_TIMEOUT (nvme_io_timeout * HZ)
  35
  36 extern unsigned char admin_timeout;
  37 #define ADMIN_TIMEOUT   (admin_timeout * HZ)
  38
  39 extern unsigned char shutdown_timeout;
  40 #define SHUTDOWN_TIMEOUT        (shutdown_timeout * HZ)
  41
  42 #define NVME_DEFAULT_KATO       5
  43 #define NVME_KATO_GRACE         10
  44
  45 extern unsigned int nvme_max_retries;
  46
  47 enum {
  48         NVME_NS_LBA             = 0,
  49         NVME_NS_LIGHTNVM        = 1,
  50 };
  51
  52 /*
  53  * List of workarounds for devices that required behavior not specified in
  54  * the standard.
  55  */
  56 enum nvme_quirks {
  57         /*
  58          * Prefers I/O aligned to a stripe size specified in a vendor
  59          * specific Identify field.
  60          */
  61         NVME_QUIRK_STRIPE_SIZE                  = (1 << 0),
  62
  63         /*
  64          * The controller doesn't handle Identify value others than 0 or 1
  65          * correctly.
  66          */
  67         NVME_QUIRK_IDENTIFY_CNS                 = (1 << 1),
  68
  69         /*
  70          * The controller deterministically returns O's on reads to discarded
  71          * logical blocks.
  72          */
  73         NVME_QUIRK_DISCARD_ZEROES               = (1 << 2),
  74
  75         /*
  76          * The controller needs a delay before starts checking the device
  77          * readiness, which is done by reading the NVME_CSTS_RDY bit.
  78          */
  79         NVME_QUIRK_DELAY_BEFORE_CHK_RDY         = (1 << 3),
  80 };
  81
  82 /*
  83  * Common request structure for NVMe passthrough.  All drivers must have
  84  * this structure as the first member of their request-private data.
  85  */
  86 struct nvme_request {
  87         struct nvme_command     *cmd;
  88         union nvme_result       result;
  89 };
  90
  91 static inline struct nvme_request *nvme_req(struct request *req)
  92 {
  93         return blk_mq_rq_to_pdu(req);
  94 }
  95
  96 /* The below value is the specific amount of delay needed before checking
  97  * readiness in case of the PCI_DEVICE(0x1c58, 0x0003), which needs the
  98  * NVME_QUIRK_DELAY_BEFORE_CHK_RDY quirk enabled. The value (in ms) was
  99  * found empirically.
 100  */
 101 #define NVME_QUIRK_DELAY_AMOUNT         2000
 102
 103 enum nvme_ctrl_state {
 104         NVME_CTRL_NEW,
 105         NVME_CTRL_LIVE,
 106         NVME_CTRL_RESETTING,
 107         NVME_CTRL_RECONNECTING,
 108         NVME_CTRL_DELETING,
 109         NVME_CTRL_DEAD,
 110 };
 111
 112 struct nvme_ctrl {
 113         enum nvme_ctrl_state state;
 114         spinlock_t lock;
 115         const struct nvme_ctrl_ops *ops;
 116         struct request_queue *admin_q;
 117         struct request_queue *connect_q;
 118         struct device *dev;
 119         struct kref kref;
 120         int instance;
 121         struct blk_mq_tag_set *tagset;
 122         struct list_head namespaces;
 123         struct mutex namespaces_mutex;
 124         struct device *device;  /* char device */
 125         struct list_head node;
 126         struct ida ns_ida;
 127
 128         char name[12];
 129         char serial[20];
 130         char model[40];
 131         char firmware_rev[8];
 132         u16 cntlid;
 133
 134         u32 ctrl_config;
 135
 136         u32 page_size;
 137         u32 max_hw_sectors;
 138         u16 oncs;
 139         u16 vid;
 140         atomic_t abort_limit;
 141         u8 event_limit;
 142         u8 vwc;
 143         u32 vs;
 144         u32 sgls;
 145         u16 kas;
 146         unsigned int kato;
 147         bool subsystem;
 148         unsigned long quirks;
 149         struct work_struct scan_work;
 150         struct work_struct async_event_work;
 151         struct delayed_work ka_work;
 152
 153         /* Fabrics only */
 154         u16 sqsize;
 155         u32 ioccsz;
 156         u32 iorcsz;
 157         u16 icdoff;
 158         u16 maxcmd;
 159         struct nvmf_ctrl_options *opts;
 160 };
 161
 162 /*
 163  * An NVM Express namespace is equivalent to a SCSI LUN
 164  */
 165 struct nvme_ns {
 166         struct list_head list;
 167
 168         struct nvme_ctrl *ctrl;
 169         struct request_queue *queue;
 170         struct gendisk *disk;
 171         struct nvm_dev *ndev;
 172         struct kref kref;
 173         int instance;
 174
 175         u8 eui[8];
 176         u8 uuid[16];
 177
 178         unsigned ns_id;
 179         int lba_shift;
 180         u16 ms;
 181         bool ext;
 182         u8 pi_type;
 183         unsigned long flags;
 184
 185 #define NVME_NS_REMOVING 0
 186 #define NVME_NS_DEAD     1
 187
 188         u64 mode_select_num_blocks;
 189         u32 mode_select_block_len;
 190 };
 191
 192 struct nvme_ctrl_ops {
 193         const char *name;
 194         struct module *module;
 195         bool is_fabrics;
 196         int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
 197         int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
 198         int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
 199         int (*reset_ctrl)(struct nvme_ctrl *ctrl);
 200         void (*free_ctrl)(struct nvme_ctrl *ctrl);
 201         void (*submit_async_event)(struct nvme_ctrl *ctrl, int aer_idx);
 202         int (*delete_ctrl)(struct nvme_ctrl *ctrl);
 203         const char *(*get_subsysnqn)(struct nvme_ctrl *ctrl);
 204         int (*get_address)(struct nvme_ctrl *ctrl, char *buf, int size);
 205 };
 206
 207 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
 208 {
 209         u32 val = 0;
 210
 211         if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
 212                 return false;
 213         return val & NVME_CSTS_RDY;
 214 }
 215
 216 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
 217 {
 218         if (!ctrl->subsystem)
 219                 return -ENOTTY;
 220         return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
 221 }
 222
 223 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
 224 {
 225         return (sector >> (ns->lba_shift - 9));
 226 }
 227
 228 static inline void nvme_cleanup_cmd(struct request *req)
 229 {
 230         if (req->rq_flags & RQF_SPECIAL_PAYLOAD) {
 231                 kfree(page_address(req->special_vec.bv_page) +
 232                       req->special_vec.bv_offset);
 233         }
 234 }
 235
 236 static inline int nvme_error_status(u16 status)
 237 {
 238         switch (status & 0x7ff) {
 239         case NVME_SC_SUCCESS:
 240                 return 0;
 241         case NVME_SC_CAP_EXCEEDED:
 242                 return -ENOSPC;
 243         default:
 244                 return -EIO;
 245         }
 246 }
 247
 248 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
 249 {
 250         return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
 251                 (jiffies - req->start_time) < req->timeout &&
 252                 req->retries < nvme_max_retries;
 253 }
 254
 255 void nvme_cancel_request(struct request *req, void *data, bool reserved);
 256 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
 257                 enum nvme_ctrl_state new_state);
 258 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
 259 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
 260 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
 261 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
 262                 const struct nvme_ctrl_ops *ops, unsigned long quirks);
 263 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
 264 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
 265 int nvme_init_identify(struct nvme_ctrl *ctrl);
 266
 267 void nvme_queue_scan(struct nvme_ctrl *ctrl);
 268 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
 269
 270 #define NVME_NR_AERS    1
 271 void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
 272                 union nvme_result *res);
 273 void nvme_queue_async_events(struct nvme_ctrl *ctrl);
 274
 275 void nvme_stop_queues(struct nvme_ctrl *ctrl);
 276 void nvme_start_queues(struct nvme_ctrl *ctrl);
 277 void nvme_kill_queues(struct nvme_ctrl *ctrl);
 278
 279 #define NVME_QID_ANY -1
 280 struct request *nvme_alloc_request(struct request_queue *q,
 281                 struct nvme_command *cmd, unsigned int flags, int qid);
 282 void nvme_requeue_req(struct request *req);
 283 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
 284                 struct nvme_command *cmd);
 285 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
 286                 void *buf, unsigned bufflen);
 287 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
 288                 union nvme_result *result, void *buffer, unsigned bufflen,
 289                 unsigned timeout, int qid, int at_head, int flags);
 290 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
 291                 void __user *ubuffer, unsigned bufflen, u32 *result,
 292                 unsigned timeout);
 293 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
 294                 void __user *ubuffer, unsigned bufflen,
 295                 void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
 296                 u32 *result, unsigned timeout);
 297 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
 298 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
 299                 struct nvme_id_ns **id);
 300 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
 301 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
 302                       void *buffer, size_t buflen, u32 *result);
 303 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
 304                       void *buffer, size_t buflen, u32 *result);
 305 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
 306 void nvme_start_keep_alive(struct nvme_ctrl *ctrl);
 307 void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
 308
 309 struct sg_io_hdr;
 310
 311 int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
 312 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
 313 int nvme_sg_get_version_num(int __user *ip);
 314
 315 #ifdef CONFIG_NVM
 316 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
 317 int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node);
 318 void nvme_nvm_unregister(struct nvme_ns *ns);
 319 int nvme_nvm_register_sysfs(struct nvme_ns *ns);
 320 void nvme_nvm_unregister_sysfs(struct nvme_ns *ns);
 321 #else
 322 static inline int nvme_nvm_register(struct nvme_ns *ns, char *disk_name,
 323                                     int node)
 324 {
 325         return 0;
 326 }
 327
 328 static inline void nvme_nvm_unregister(struct nvme_ns *ns) {};
 329 static inline int nvme_nvm_register_sysfs(struct nvme_ns *ns)
 330 {
 331         return 0;
 332 }
 333 static inline void nvme_nvm_unregister_sysfs(struct nvme_ns *ns) {};
 334 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
 335 {
 336         return 0;
 337 }
 338 #endif /* CONFIG_NVM */
 339
 340 static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
 341 {
 342         return dev_to_disk(dev)->private_data;
 343 }
 344
 345 int __init nvme_core_init(void);
 346 void nvme_core_exit(void);
 347
 348 #endif /* _NVME_H */