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         u32 stripe_size;
 139         u16 oncs;
 140         u16 vid;
 141         atomic_t abort_limit;
 142         u8 event_limit;
 143         u8 vwc;
 144         u32 vs;
 145         u32 sgls;
 146         u16 kas;
 147         unsigned int kato;
 148         bool subsystem;
 149         unsigned long quirks;
 150         struct work_struct scan_work;
 151         struct work_struct async_event_work;
 152         struct delayed_work ka_work;
 153
 154         /* Fabrics only */
 155         u16 sqsize;
 156         u32 ioccsz;
 157         u32 iorcsz;
 158         u16 icdoff;
 159         u16 maxcmd;
 160         struct nvmf_ctrl_options *opts;
 161 };
 162
 163 /*
 164  * An NVM Express namespace is equivalent to a SCSI LUN
 165  */
 166 struct nvme_ns {
 167         struct list_head list;
 168
 169         struct nvme_ctrl *ctrl;
 170         struct request_queue *queue;
 171         struct gendisk *disk;
 172         struct nvm_dev *ndev;
 173         struct kref kref;
 174         int instance;
 175
 176         u8 eui[8];
 177         u8 uuid[16];
 178
 179         unsigned ns_id;
 180         int lba_shift;
 181         u16 ms;
 182         bool ext;
 183         u8 pi_type;
 184         unsigned long flags;
 185
 186 #define NVME_NS_REMOVING 0
 187 #define NVME_NS_DEAD     1
 188
 189         u64 mode_select_num_blocks;
 190         u32 mode_select_block_len;
 191 };
 192
 193 struct nvme_ctrl_ops {
 194         const char *name;
 195         struct module *module;
 196         bool is_fabrics;
 197         int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
 198         int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
 199         int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
 200         int (*reset_ctrl)(struct nvme_ctrl *ctrl);
 201         void (*free_ctrl)(struct nvme_ctrl *ctrl);
 202         void (*submit_async_event)(struct nvme_ctrl *ctrl, int aer_idx);
 203         int (*delete_ctrl)(struct nvme_ctrl *ctrl);
 204         const char *(*get_subsysnqn)(struct nvme_ctrl *ctrl);
 205         int (*get_address)(struct nvme_ctrl *ctrl, char *buf, int size);
 206 };
 207
 208 static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
 209 {
 210         u32 val = 0;
 211
 212         if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
 213                 return false;
 214         return val & NVME_CSTS_RDY;
 215 }
 216
 217 static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
 218 {
 219         if (!ctrl->subsystem)
 220                 return -ENOTTY;
 221         return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
 222 }
 223
 224 static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
 225 {
 226         return (sector >> (ns->lba_shift - 9));
 227 }
 228
 229 static inline unsigned nvme_map_len(struct request *rq)
 230 {
 231         if (req_op(rq) == REQ_OP_DISCARD)
 232                 return sizeof(struct nvme_dsm_range);
 233         else
 234                 return blk_rq_bytes(rq);
 235 }
 236
 237 static inline void nvme_cleanup_cmd(struct request *req)
 238 {
 239         if (req_op(req) == REQ_OP_DISCARD)
 240                 kfree(req->completion_data);
 241 }
 242
 243 static inline int nvme_error_status(u16 status)
 244 {
 245         switch (status & 0x7ff) {
 246         case NVME_SC_SUCCESS:
 247                 return 0;
 248         case NVME_SC_CAP_EXCEEDED:
 249                 return -ENOSPC;
 250         default:
 251                 return -EIO;
 252         }
 253 }
 254
 255 static inline bool nvme_req_needs_retry(struct request *req, u16 status)
 256 {
 257         return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
 258                 (jiffies - req->start_time) < req->timeout &&
 259                 req->retries < nvme_max_retries;
 260 }
 261
 262 void nvme_cancel_request(struct request *req, void *data, bool reserved);
 263 bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
 264                 enum nvme_ctrl_state new_state);
 265 int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
 266 int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
 267 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
 268 int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
 269                 const struct nvme_ctrl_ops *ops, unsigned long quirks);
 270 void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
 271 void nvme_put_ctrl(struct nvme_ctrl *ctrl);
 272 int nvme_init_identify(struct nvme_ctrl *ctrl);
 273
 274 void nvme_queue_scan(struct nvme_ctrl *ctrl);
 275 void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
 276
 277 #define NVME_NR_AERS    1
 278 void nvme_complete_async_event(struct nvme_ctrl *ctrl, __le16 status,
 279                 union nvme_result *res);
 280 void nvme_queue_async_events(struct nvme_ctrl *ctrl);
 281
 282 void nvme_stop_queues(struct nvme_ctrl *ctrl);
 283 void nvme_start_queues(struct nvme_ctrl *ctrl);
 284 void nvme_kill_queues(struct nvme_ctrl *ctrl);
 285
 286 #define NVME_QID_ANY -1
 287 struct request *nvme_alloc_request(struct request_queue *q,
 288                 struct nvme_command *cmd, unsigned int flags, int qid);
 289 void nvme_requeue_req(struct request *req);
 290 int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
 291                 struct nvme_command *cmd);
 292 int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
 293                 void *buf, unsigned bufflen);
 294 int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
 295                 union nvme_result *result, void *buffer, unsigned bufflen,
 296                 unsigned timeout, int qid, int at_head, int flags);
 297 int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
 298                 void __user *ubuffer, unsigned bufflen, u32 *result,
 299                 unsigned timeout);
 300 int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
 301                 void __user *ubuffer, unsigned bufflen,
 302                 void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
 303                 u32 *result, unsigned timeout);
 304 int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
 305 int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
 306                 struct nvme_id_ns **id);
 307 int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
 308 int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
 309                       void *buffer, size_t buflen, u32 *result);
 310 int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
 311                       void *buffer, size_t buflen, u32 *result);
 312 int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
 313 void nvme_start_keep_alive(struct nvme_ctrl *ctrl);
 314 void nvme_stop_keep_alive(struct nvme_ctrl *ctrl);
 315
 316 struct sg_io_hdr;
 317
 318 int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
 319 int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
 320 int nvme_sg_get_version_num(int __user *ip);
 321
 322 #ifdef CONFIG_NVM
 323 int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
 324 int nvme_nvm_register(struct nvme_ns *ns, char *disk_name, int node,
 325                       const struct attribute_group *attrs);
 326 void nvme_nvm_unregister(struct nvme_ns *ns);
 327
 328 static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
 329 {
 330         if (dev->type->devnode)
 331                 return dev_to_disk(dev)->private_data;
 332
 333         return (container_of(dev, struct nvm_dev, dev))->private_data;
 334 }
 335 #else
 336 static inline int nvme_nvm_register(struct nvme_ns *ns, char *disk_name,
 337                                     int node,
 338                                     const struct attribute_group *attrs)
 339 {
 340         return 0;
 341 }
 342
 343 static inline void nvme_nvm_unregister(struct nvme_ns *ns) {};
 344
 345 static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
 346 {
 347         return 0;
 348 }
 349 static inline struct nvme_ns *nvme_get_ns_from_dev(struct device *dev)
 350 {
 351         return dev_to_disk(dev)->private_data;
 352 }
 353 #endif /* CONFIG_NVM */
 354
 355 int __init nvme_core_init(void);
 356 void nvme_core_exit(void);
 357
 358 #endif /* _NVME_H */