include/scsi/scsi_device.h

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