include/scsi/scsi_device.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _SCSI_SCSI_DEVICE_H
   3 #define _SCSI_SCSI_DEVICE_H
   4
   5 #include <linux/list.h>
   6 #include <linux/spinlock.h>
   7 #include <linux/workqueue.h>
   8 #include <linux/blkdev.h>
   9 #include <scsi/scsi.h>
  10 #include <linux/atomic.h>
  11
  12 struct device;
  13 struct request_queue;
  14 struct scsi_cmnd;
  15 struct scsi_lun;
  16 struct scsi_sense_hdr;
  17
  18 typedef __u64 __bitwise blist_flags_t;
  19
  20 #define SCSI_SENSE_BUFFERSIZE   96
  21
  22 struct scsi_mode_data {
  23         __u32   length;
  24         __u16   block_descriptor_length;
  25         __u8    medium_type;
  26         __u8    device_specific;
  27         __u8    header_length;
  28         __u8    longlba:1;
  29 };
  30
  31 /*
  32  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
  33  * (for the ascii descriptions) and the state model enforcer:
  34  * scsi_lib:scsi_device_set_state().
  35  */
  36 enum scsi_device_state {
  37         SDEV_CREATED = 1,       /* device created but not added to sysfs
  38                                  * Only internal commands allowed (for inq) */
  39         SDEV_RUNNING,           /* device properly configured
  40                                  * All commands allowed */
  41         SDEV_CANCEL,            /* beginning to delete device
  42                                  * Only error handler commands allowed */
  43         SDEV_DEL,               /* device deleted
  44                                  * no commands allowed */
  45         SDEV_QUIESCE,           /* Device quiescent.  No block commands
  46                                  * will be accepted, only specials (which
  47                                  * originate in the mid-layer) */
  48         SDEV_OFFLINE,           /* Device offlined (by error handling or
  49                                  * user request */
  50         SDEV_TRANSPORT_OFFLINE, /* Offlined by transport class error handler */
  51         SDEV_BLOCK,             /* Device blocked by scsi lld.  No
  52                                  * scsi commands from user or midlayer
  53                                  * should be issued to the scsi
  54                                  * lld. */
  55         SDEV_CREATED_BLOCK,     /* same as above but for created devices */
  56 };
  57
  58 enum scsi_scan_mode {
  59         SCSI_SCAN_INITIAL = 0,
  60         SCSI_SCAN_RESCAN,
  61         SCSI_SCAN_MANUAL,
  62 };
  63
  64 enum scsi_device_event {
  65         SDEV_EVT_MEDIA_CHANGE   = 1,    /* media has changed */
  66         SDEV_EVT_INQUIRY_CHANGE_REPORTED,               /* 3F 03  UA reported */
  67         SDEV_EVT_CAPACITY_CHANGE_REPORTED,              /* 2A 09  UA reported */
  68         SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,       /* 38 07  UA reported */
  69         SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,        /* 2A 01  UA reported */
  70         SDEV_EVT_LUN_CHANGE_REPORTED,                   /* 3F 0E  UA reported */
  71         SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,            /* 2A 06  UA reported */
  72         SDEV_EVT_POWER_ON_RESET_OCCURRED,               /* 29 00  UA reported */
  73
  74         SDEV_EVT_FIRST          = SDEV_EVT_MEDIA_CHANGE,
  75         SDEV_EVT_LAST           = SDEV_EVT_POWER_ON_RESET_OCCURRED,
  76
  77         SDEV_EVT_MAXBITS        = SDEV_EVT_LAST + 1
  78 };
  79
  80 struct scsi_event {
  81         enum scsi_device_event  evt_type;
  82         struct list_head        node;
  83
  84         /* put union of data structures, for non-simple event types,
  85          * here
  86          */
  87 };
  88
  89 /**
  90  * struct scsi_vpd - SCSI Vital Product Data
  91  * @rcu: For kfree_rcu().
  92  * @len: Length in bytes of @data.
  93  * @data: VPD data as defined in various T10 SCSI standard documents.
  94  */
  95 struct scsi_vpd {
  96         struct rcu_head rcu;
  97         int             len;
  98         unsigned char   data[];
  99 };
 100
 101 struct scsi_device {
 102         struct Scsi_Host *host;
 103         struct request_queue *request_queue;
 104
 105         /* the next two are protected by the host->host_lock */
 106         struct list_head    siblings;   /* list of all devices on this host */
 107         struct list_head    same_target_siblings; /* just the devices sharing same target id */
 108
 109         atomic_t device_busy;           /* commands actually active on LLDD */
 110         atomic_t device_blocked;        /* Device returned QUEUE_FULL. */
 111
 112         spinlock_t list_lock;
 113         struct list_head cmd_list;      /* queue of in use SCSI Command structures */
 114         struct list_head starved_entry;
 115         unsigned short queue_depth;     /* How deep of a queue we want */
 116         unsigned short max_queue_depth; /* max queue depth */
 117         unsigned short last_queue_full_depth; /* These two are used by */
 118         unsigned short last_queue_full_count; /* scsi_track_queue_full() */
 119         unsigned long last_queue_full_time;     /* last queue full time */
 120         unsigned long queue_ramp_up_period;     /* ramp up period in jiffies */
 121 #define SCSI_DEFAULT_RAMP_UP_PERIOD     (120 * HZ)
 122
 123         unsigned long last_queue_ramp_up;       /* last queue ramp up time */
 124
 125         unsigned int id, channel;
 126         u64 lun;
 127         unsigned int manufacturer;      /* Manufacturer of device, for using
 128                                          * vendor-specific cmd's */
 129         unsigned sector_size;   /* size in bytes */
 130
 131         void *hostdata;         /* available to low-level driver */
 132         unsigned char type;
 133         char scsi_level;
 134         char inq_periph_qual;   /* PQ from INQUIRY data */
 135         struct mutex inquiry_mutex;
 136         unsigned char inquiry_len;      /* valid bytes in 'inquiry' */
 137         unsigned char * inquiry;        /* INQUIRY response data */
 138         const char * vendor;            /* [back_compat] point into 'inquiry' ... */
 139         const char * model;             /* ... after scan; point to static string */
 140         const char * rev;               /* ... "nullnullnullnull" before scan */
 141
 142 #define SCSI_VPD_PG_LEN                255
 143         struct scsi_vpd __rcu *vpd_pg0;
 144         struct scsi_vpd __rcu *vpd_pg83;
 145         struct scsi_vpd __rcu *vpd_pg80;
 146         struct scsi_vpd __rcu *vpd_pg89;
 147         unsigned char current_tag;      /* current tag */
 148         struct scsi_target      *sdev_target;   /* used only for single_lun */
 149
 150         blist_flags_t           sdev_bflags; /* black/white flags as also found in
 151                                  * scsi_devinfo.[hc]. For now used only to
 152                                  * pass settings from slave_alloc to scsi
 153                                  * core. */
 154         unsigned int eh_timeout; /* Error handling timeout */
 155         unsigned removable:1;
 156         unsigned changed:1;     /* Data invalid due to media change */
 157         unsigned busy:1;        /* Used to prevent races */
 158         unsigned lockable:1;    /* Able to prevent media removal */
 159         unsigned locked:1;      /* Media removal disabled */
 160         unsigned borken:1;      /* Tell the Seagate driver to be
 161                                  * painfully slow on this device */
 162         unsigned disconnect:1;  /* can disconnect */
 163         unsigned soft_reset:1;  /* Uses soft reset option */
 164         unsigned sdtr:1;        /* Device supports SDTR messages */
 165         unsigned wdtr:1;        /* Device supports WDTR messages */
 166         unsigned ppr:1;         /* Device supports PPR messages */
 167         unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
 168         unsigned simple_tags:1; /* simple queue tag messages are enabled */
 169         unsigned was_reset:1;   /* There was a bus reset on the bus for
 170                                  * this device */
 171         unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
 172                                      * because we did a bus reset. */
 173         unsigned use_10_for_rw:1; /* first try 10-byte read / write */
 174         unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
 175         unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */
 176         unsigned no_report_opcodes:1;   /* no REPORT SUPPORTED OPERATION CODES */
 177         unsigned no_write_same:1;       /* no WRITE SAME command */
 178         unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
 179         unsigned skip_ms_page_8:1;      /* do not use MODE SENSE page 0x08 */
 180         unsigned skip_ms_page_3f:1;     /* do not use MODE SENSE page 0x3f */
 181         unsigned skip_vpd_pages:1;      /* do not read VPD pages */
 182         unsigned try_vpd_pages:1;       /* attempt to read VPD pages */
 183         unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
 184         unsigned no_start_on_add:1;     /* do not issue start on add */
 185         unsigned allow_restart:1; /* issue START_UNIT in error handler */
 186         unsigned manage_start_stop:1;   /* Let HLD (sd) manage start/stop */
 187         unsigned start_stop_pwr_cond:1; /* Set power cond. in START_STOP_UNIT */
 188         unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
 189         unsigned select_no_atn:1;
 190         unsigned fix_capacity:1;        /* READ_CAPACITY is too high by 1 */
 191         unsigned guess_capacity:1;      /* READ_CAPACITY might be too high by 1 */
 192         unsigned retry_hwerror:1;       /* Retry HARDWARE_ERROR */
 193         unsigned last_sector_bug:1;     /* do not use multisector accesses on
 194                                            SD_LAST_BUGGY_SECTORS */
 195         unsigned no_read_disc_info:1;   /* Avoid READ_DISC_INFO cmds */
 196         unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
 197         unsigned try_rc_10_first:1;     /* Try READ_CAPACACITY_10 first */
 198         unsigned security_supported:1;  /* Supports Security Protocols */
 199         unsigned is_visible:1;  /* is the device visible in sysfs */
 200         unsigned wce_default_on:1;      /* Cache is ON by default */
 201         unsigned no_dif:1;      /* T10 PI (DIF) should be disabled */
 202         unsigned broken_fua:1;          /* Don't set FUA bit */
 203         unsigned lun_in_cdb:1;          /* Store LUN bits in CDB[1] */
 204         unsigned unmap_limit_for_ws:1;  /* Use the UNMAP limit for WRITE SAME */
 205         unsigned rpm_autosuspend:1;     /* Enable runtime autosuspend at device
 206                                          * creation time */
 207         atomic_t disk_events_disable_depth; /* disable depth for disk events */
 208
 209         DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
 210         DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
 211         struct list_head event_list;    /* asserted events */
 212         struct work_struct event_work;
 213
 214         unsigned int max_device_blocked; /* what device_blocked counts down from  */
 215 #define SCSI_DEFAULT_DEVICE_BLOCKED     3
 216
 217         atomic_t iorequest_cnt;
 218         atomic_t iodone_cnt;
 219         atomic_t ioerr_cnt;
 220
 221         struct device           sdev_gendev,
 222                                 sdev_dev;
 223
 224         struct execute_work     ew; /* used to get process context on put */
 225         struct work_struct      requeue_work;
 226
 227         struct scsi_device_handler *handler;
 228         void                    *handler_data;
 229
 230         unsigned char           access_state;
 231         struct mutex            state_mutex;
 232         enum scsi_device_state sdev_state;
 233         struct task_struct      *quiesced_by;
 234         unsigned long           sdev_data[0];
 235 } __attribute__((aligned(sizeof(unsigned long))));
 236
 237 #define to_scsi_device(d)       \
 238         container_of(d, struct scsi_device, sdev_gendev)
 239 #define class_to_sdev(d)        \
 240         container_of(d, struct scsi_device, sdev_dev)
 241 #define transport_class_to_sdev(class_dev) \
 242         to_scsi_device(class_dev->parent)
 243
 244 #define sdev_dbg(sdev, fmt, a...) \
 245         dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)
 246
 247 /*
 248  * like scmd_printk, but the device name is passed in
 249  * as a string pointer
 250  */
 251 __printf(4, 5) void
 252 sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
 253                 const char *, ...);
 254
 255 #define sdev_printk(l, sdev, fmt, a...)                         \
 256         sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
 257
 258 __printf(3, 4) void
 259 scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
 260
 261 #define scmd_dbg(scmd, fmt, a...)                                          \
 262         do {                                                               \
 263                 if ((scmd)->request->rq_disk)                              \
 264                         sdev_dbg((scmd)->device, "[%s] " fmt,              \
 265                                  (scmd)->request->rq_disk->disk_name, ##a);\
 266                 else                                                       \
 267                         sdev_dbg((scmd)->device, fmt, ##a);                \
 268         } while (0)
 269
 270 enum scsi_target_state {
 271         STARGET_CREATED = 1,
 272         STARGET_RUNNING,
 273         STARGET_REMOVE,
 274         STARGET_CREATED_REMOVE,
 275         STARGET_DEL,
 276 };
 277
 278 /*
 279  * scsi_target: representation of a scsi target, for now, this is only
 280  * used for single_lun devices. If no one has active IO to the target,
 281  * starget_sdev_user is NULL, else it points to the active sdev.
 282  */
 283 struct scsi_target {
 284         struct scsi_device      *starget_sdev_user;
 285         struct list_head        siblings;
 286         struct list_head        devices;
 287         struct device           dev;
 288         struct kref             reap_ref; /* last put renders target invisible */
 289         unsigned int            channel;
 290         unsigned int            id; /* target id ... replace
 291                                      * scsi_device.id eventually */
 292         unsigned int            create:1; /* signal that it needs to be added */
 293         unsigned int            single_lun:1;   /* Indicates we should only
 294                                                  * allow I/O to one of the luns
 295                                                  * for the device at a time. */
 296         unsigned int            pdt_1f_for_no_lun:1;    /* PDT = 0x1f
 297                                                  * means no lun present. */
 298         unsigned int            no_report_luns:1;       /* Don't use
 299                                                  * REPORT LUNS for scanning. */
 300         unsigned int            expecting_lun_change:1; /* A device has reported
 301                                                  * a 3F/0E UA, other devices on
 302                                                  * the same target will also. */
 303         /* commands actually active on LLD. */
 304         atomic_t                target_busy;
 305         atomic_t                target_blocked;
 306
 307         /*
 308          * LLDs should set this in the slave_alloc host template callout.
 309          * If set to zero then there is not limit.
 310          */
 311         unsigned int            can_queue;
 312         unsigned int            max_target_blocked;
 313 #define SCSI_DEFAULT_TARGET_BLOCKED     3
 314
 315         char                    scsi_level;
 316         enum scsi_target_state  state;
 317         void                    *hostdata; /* available to low-level driver */
 318         unsigned long           starget_data[0]; /* for the transport */
 319         /* starget_data must be the last element!!!! */
 320 } __attribute__((aligned(sizeof(unsigned long))));
 321
 322 #define to_scsi_target(d)       container_of(d, struct scsi_target, dev)
 323 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
 324 {
 325         return to_scsi_target(sdev->sdev_gendev.parent);
 326 }
 327 #define transport_class_to_starget(class_dev) \
 328         to_scsi_target(class_dev->parent)
 329
 330 #define starget_printk(prefix, starget, fmt, a...)      \
 331         dev_printk(prefix, &(starget)->dev, fmt, ##a)
 332
 333 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
 334                 uint, uint, u64, void *hostdata);
 335 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
 336                            uint target, u64 lun);
 337 extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
 338 extern void scsi_remove_device(struct scsi_device *);
 339 extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
 340 void scsi_attach_vpd(struct scsi_device *sdev);
 341
 342 extern struct scsi_device *scsi_device_from_queue(struct request_queue *q);
 343 extern int __must_check scsi_device_get(struct scsi_device *);
 344 extern void scsi_device_put(struct scsi_device *);
 345 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
 346                                               uint, uint, u64);
 347 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
 348                                                 uint, uint, u64);
 349 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
 350                                                         u64);
 351 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
 352                                                           u64);
 353 extern void starget_for_each_device(struct scsi_target *, void *,
 354                      void (*fn)(struct scsi_device *, void *));
 355 extern void __starget_for_each_device(struct scsi_target *, void *,
 356                                       void (*fn)(struct scsi_device *,
 357                                                  void *));
 358
 359 /* only exposed to implement shost_for_each_device */
 360 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
 361                                                   struct scsi_device *);
 362
 363 /**
 364  * shost_for_each_device - iterate over all devices of a host
 365  * @sdev: the &struct scsi_device to use as a cursor
 366  * @shost: the &struct scsi_host to iterate over
 367  *
 368  * Iterator that returns each device attached to @shost.  This loop
 369  * takes a reference on each device and releases it at the end.  If
 370  * you break out of the loop, you must call scsi_device_put(sdev).
 371  */
 372 #define shost_for_each_device(sdev, shost) \
 373         for ((sdev) = __scsi_iterate_devices((shost), NULL); \
 374              (sdev); \
 375              (sdev) = __scsi_iterate_devices((shost), (sdev)))
 376
 377 /**
 378  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
 379  * @sdev: the &struct scsi_device to use as a cursor
 380  * @shost: the &struct scsi_host to iterate over
 381  *
 382  * Iterator that returns each device attached to @shost.  It does _not_
 383  * take a reference on the scsi_device, so the whole loop must be
 384  * protected by shost->host_lock.
 385  *
 386  * Note: The only reason to use this is because you need to access the
 387  * device list in interrupt context.  Otherwise you really want to use
 388  * shost_for_each_device instead.
 389  */
 390 #define __shost_for_each_device(sdev, shost) \
 391         list_for_each_entry((sdev), &((shost)->__devices), siblings)
 392
 393 extern int scsi_change_queue_depth(struct scsi_device *, int);
 394 extern int scsi_track_queue_full(struct scsi_device *, int);
 395
 396 extern int scsi_set_medium_removal(struct scsi_device *, char);
 397
 398 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 399                            unsigned char *buffer, int len, int timeout,
 400                            int retries, struct scsi_mode_data *data,
 401                            struct scsi_sense_hdr *);
 402 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
 403                             int modepage, unsigned char *buffer, int len,
 404                             int timeout, int retries,
 405                             struct scsi_mode_data *data,
 406                             struct scsi_sense_hdr *);
 407 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
 408                                 int retries, struct scsi_sense_hdr *sshdr);
 409 extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
 410                              int buf_len);
 411 extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
 412                               unsigned int len, unsigned char opcode);
 413 extern int scsi_device_set_state(struct scsi_device *sdev,
 414                                  enum scsi_device_state state);
 415 extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
 416                                           gfp_t gfpflags);
 417 extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
 418 extern void sdev_evt_send_simple(struct scsi_device *sdev,
 419                           enum scsi_device_event evt_type, gfp_t gfpflags);
 420 extern int scsi_device_quiesce(struct scsi_device *sdev);
 421 extern void scsi_device_resume(struct scsi_device *sdev);
 422 extern void scsi_target_quiesce(struct scsi_target *);
 423 extern void scsi_target_resume(struct scsi_target *);
 424 extern void scsi_scan_target(struct device *parent, unsigned int channel,
 425                              unsigned int id, u64 lun,
 426                              enum scsi_scan_mode rescan);
 427 extern void scsi_target_reap(struct scsi_target *);
 428 extern void scsi_target_block(struct device *);
 429 extern void scsi_target_unblock(struct device *, enum scsi_device_state);
 430 extern void scsi_remove_target(struct device *);
 431 extern const char *scsi_device_state_name(enum scsi_device_state);
 432 extern int scsi_is_sdev_device(const struct device *);
 433 extern int scsi_is_target_device(const struct device *);
 434 extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
 435 extern int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 436                         int data_direction, void *buffer, unsigned bufflen,
 437                         unsigned char *sense, struct scsi_sense_hdr *sshdr,
 438                         int timeout, int retries, u64 flags,
 439                         req_flags_t rq_flags, int *resid);
 440 /* Make sure any sense buffer is the correct size. */
 441 #define scsi_execute(sdev, cmd, data_direction, buffer, bufflen, sense, \
 442                      sshdr, timeout, retries, flags, rq_flags, resid)   \
 443 ({                                                                      \
 444         BUILD_BUG_ON((sense) != NULL &&                                 \
 445                      sizeof(sense) != SCSI_SENSE_BUFFERSIZE);           \
 446         __scsi_execute(sdev, cmd, data_direction, buffer, bufflen,      \
 447                        sense, sshdr, timeout, retries, flags, rq_flags, \
 448                        resid);                                          \
 449 })
 450 static inline int scsi_execute_req(struct scsi_device *sdev,
 451         const unsigned char *cmd, int data_direction, void *buffer,
 452         unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
 453         int retries, int *resid)
 454 {
 455         return scsi_execute(sdev, cmd, data_direction, buffer,
 456                 bufflen, NULL, sshdr, timeout, retries,  0, 0, resid);
 457 }
 458 extern void sdev_disable_disk_events(struct scsi_device *sdev);
 459 extern void sdev_enable_disk_events(struct scsi_device *sdev);
 460 extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
 461 extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
 462
 463 #ifdef CONFIG_PM
 464 extern int scsi_autopm_get_device(struct scsi_device *);
 465 extern void scsi_autopm_put_device(struct scsi_device *);
 466 #else
 467 static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
 468 static inline void scsi_autopm_put_device(struct scsi_device *d) {}
 469 #endif /* CONFIG_PM */
 470
 471 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
 472 {
 473         return device_reprobe(&sdev->sdev_gendev);
 474 }
 475
 476 static inline unsigned int sdev_channel(struct scsi_device *sdev)
 477 {
 478         return sdev->channel;
 479 }
 480
 481 static inline unsigned int sdev_id(struct scsi_device *sdev)
 482 {
 483         return sdev->id;
 484 }
 485
 486 #define scmd_id(scmd) sdev_id((scmd)->device)
 487 #define scmd_channel(scmd) sdev_channel((scmd)->device)
 488
 489 /*
 490  * checks for positions of the SCSI state machine
 491  */
 492 static inline int scsi_device_online(struct scsi_device *sdev)
 493 {
 494         return (sdev->sdev_state != SDEV_OFFLINE &&
 495                 sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
 496                 sdev->sdev_state != SDEV_DEL);
 497 }
 498 static inline int scsi_device_blocked(struct scsi_device *sdev)
 499 {
 500         return sdev->sdev_state == SDEV_BLOCK ||
 501                 sdev->sdev_state == SDEV_CREATED_BLOCK;
 502 }
 503 static inline int scsi_device_created(struct scsi_device *sdev)
 504 {
 505         return sdev->sdev_state == SDEV_CREATED ||
 506                 sdev->sdev_state == SDEV_CREATED_BLOCK;
 507 }
 508
 509 int scsi_internal_device_block_nowait(struct scsi_device *sdev);
 510 int scsi_internal_device_unblock_nowait(struct scsi_device *sdev,
 511                                         enum scsi_device_state new_state);
 512
 513 /* accessor functions for the SCSI parameters */
 514 static inline int scsi_device_sync(struct scsi_device *sdev)
 515 {
 516         return sdev->sdtr;
 517 }
 518 static inline int scsi_device_wide(struct scsi_device *sdev)
 519 {
 520         return sdev->wdtr;
 521 }
 522 static inline int scsi_device_dt(struct scsi_device *sdev)
 523 {
 524         return sdev->ppr;
 525 }
 526 static inline int scsi_device_dt_only(struct scsi_device *sdev)
 527 {
 528         if (sdev->inquiry_len < 57)
 529                 return 0;
 530         return (sdev->inquiry[56] & 0x0c) == 0x04;
 531 }
 532 static inline int scsi_device_ius(struct scsi_device *sdev)
 533 {
 534         if (sdev->inquiry_len < 57)
 535                 return 0;
 536         return sdev->inquiry[56] & 0x01;
 537 }
 538 static inline int scsi_device_qas(struct scsi_device *sdev)
 539 {
 540         if (sdev->inquiry_len < 57)
 541                 return 0;
 542         return sdev->inquiry[56] & 0x02;
 543 }
 544 static inline int scsi_device_enclosure(struct scsi_device *sdev)
 545 {
 546         return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
 547 }
 548
 549 static inline int scsi_device_protection(struct scsi_device *sdev)
 550 {
 551         if (sdev->no_dif)
 552                 return 0;
 553
 554         return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
 555 }
 556
 557 static inline int scsi_device_tpgs(struct scsi_device *sdev)
 558 {
 559         return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
 560 }
 561
 562 /**
 563  * scsi_device_supports_vpd - test if a device supports VPD pages
 564  * @sdev: the &struct scsi_device to test
 565  *
 566  * If the 'try_vpd_pages' flag is set it takes precedence.
 567  * Otherwise we will assume VPD pages are supported if the
 568  * SCSI level is at least SPC-3 and 'skip_vpd_pages' is not set.
 569  */
 570 static inline int scsi_device_supports_vpd(struct scsi_device *sdev)
 571 {
 572         /* Attempt VPD inquiry if the device blacklist explicitly calls
 573          * for it.
 574          */
 575         if (sdev->try_vpd_pages)
 576                 return 1;
 577         /*
 578          * Although VPD inquiries can go to SCSI-2 type devices,
 579          * some USB ones crash on receiving them, and the pages
 580          * we currently ask for are mandatory for SPC-2 and beyond
 581          */
 582         if (sdev->scsi_level >= SCSI_SPC_2 && !sdev->skip_vpd_pages)
 583                 return 1;
 584         return 0;
 585 }
 586
 587 #define MODULE_ALIAS_SCSI_DEVICE(type) \
 588         MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 589 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
 590
 591 #endif /* _SCSI_SCSI_DEVICE_H */