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_device_event {
  54         SDEV_EVT_MEDIA_CHANGE   = 1,    /* media has changed */
  55         SDEV_EVT_INQUIRY_CHANGE_REPORTED,               /* 3F 03  UA reported */
  56         SDEV_EVT_CAPACITY_CHANGE_REPORTED,              /* 2A 09  UA reported */
  57         SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,       /* 38 07  UA reported */
  58         SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,        /* 2A 01  UA reported */
  59         SDEV_EVT_LUN_CHANGE_REPORTED,                   /* 3F 0E  UA reported */
  60         SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,            /* 2A 06  UA reported */
  61
  62         SDEV_EVT_FIRST          = SDEV_EVT_MEDIA_CHANGE,
  63         SDEV_EVT_LAST           = SDEV_EVT_ALUA_STATE_CHANGE_REPORTED,
  64
  65         SDEV_EVT_MAXBITS        = SDEV_EVT_LAST + 1
  66 };
  67
  68 struct scsi_event {
  69         enum scsi_device_event  evt_type;
  70         struct list_head        node;
  71
  72         /* put union of data structures, for non-simple event types,
  73          * here
  74          */
  75 };
  76
  77 struct scsi_device {
  78         struct Scsi_Host *host;
  79         struct request_queue *request_queue;
  80
  81         /* the next two are protected by the host->host_lock */
  82         struct list_head    siblings;   /* list of all devices on this host */
  83         struct list_head    same_target_siblings; /* just the devices sharing same target id */
  84
  85         atomic_t device_busy;           /* commands actually active on LLDD */
  86         atomic_t device_blocked;        /* Device returned QUEUE_FULL. */
  87
  88         spinlock_t list_lock;
  89         struct list_head cmd_list;      /* queue of in use SCSI Command structures */
  90         struct list_head starved_entry;
  91         struct scsi_cmnd *current_cmnd; /* currently active command */
  92         unsigned short queue_depth;     /* How deep of a queue we want */
  93         unsigned short max_queue_depth; /* max queue depth */
  94         unsigned short last_queue_full_depth; /* These two are used by */
  95         unsigned short last_queue_full_count; /* scsi_track_queue_full() */
  96         unsigned long last_queue_full_time;     /* last queue full time */
  97         unsigned long queue_ramp_up_period;     /* ramp up period in jiffies */
  98 #define SCSI_DEFAULT_RAMP_UP_PERIOD     (120 * HZ)
  99
 100         unsigned long last_queue_ramp_up;       /* last queue ramp up time */
 101
 102         unsigned int id, channel;
 103         u64 lun;
 104         unsigned int manufacturer;      /* Manufacturer of device, for using
 105                                          * vendor-specific cmd's */
 106         unsigned sector_size;   /* size in bytes */
 107
 108         void *hostdata;         /* available to low-level driver */
 109         char type;
 110         char scsi_level;
 111         char inq_periph_qual;   /* PQ from INQUIRY data */
 112         struct mutex inquiry_mutex;
 113         unsigned char inquiry_len;      /* valid bytes in 'inquiry' */
 114         unsigned char * inquiry;        /* INQUIRY response data */
 115         const char * vendor;            /* [back_compat] point into 'inquiry' ... */
 116         const char * model;             /* ... after scan; point to static string */
 117         const char * rev;               /* ... "nullnullnullnull" before scan */
 118
 119 #define SCSI_VPD_PG_LEN                255
 120         int vpd_pg83_len;
 121         unsigned char __rcu *vpd_pg83;
 122         int vpd_pg80_len;
 123         unsigned char __rcu *vpd_pg80;
 124         unsigned char current_tag;      /* current tag */
 125         struct scsi_target      *sdev_target;   /* used only for single_lun */
 126
 127         unsigned int    sdev_bflags; /* black/white flags as also found in
 128                                  * scsi_devinfo.[hc]. For now used only to
 129                                  * pass settings from slave_alloc to scsi
 130                                  * core. */
 131         unsigned int eh_timeout; /* Error handling timeout */
 132         unsigned removable:1;
 133         unsigned changed:1;     /* Data invalid due to media change */
 134         unsigned busy:1;        /* Used to prevent races */
 135         unsigned lockable:1;    /* Able to prevent media removal */
 136         unsigned locked:1;      /* Media removal disabled */
 137         unsigned borken:1;      /* Tell the Seagate driver to be
 138                                  * painfully slow on this device */
 139         unsigned disconnect:1;  /* can disconnect */
 140         unsigned soft_reset:1;  /* Uses soft reset option */
 141         unsigned sdtr:1;        /* Device supports SDTR messages */
 142         unsigned wdtr:1;        /* Device supports WDTR messages */
 143         unsigned ppr:1;         /* Device supports PPR messages */
 144         unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
 145         unsigned simple_tags:1; /* simple queue tag messages are enabled */
 146         unsigned was_reset:1;   /* There was a bus reset on the bus for
 147                                  * this device */
 148         unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
 149                                      * because we did a bus reset. */
 150         unsigned use_10_for_rw:1; /* first try 10-byte read / write */
 151         unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
 152         unsigned no_report_opcodes:1;   /* no REPORT SUPPORTED OPERATION CODES */
 153         unsigned no_write_same:1;       /* no WRITE SAME command */
 154         unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
 155         unsigned skip_ms_page_8:1;      /* do not use MODE SENSE page 0x08 */
 156         unsigned skip_ms_page_3f:1;     /* do not use MODE SENSE page 0x3f */
 157         unsigned skip_vpd_pages:1;      /* do not read VPD pages */
 158         unsigned try_vpd_pages:1;       /* attempt to read VPD pages */
 159         unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
 160         unsigned no_start_on_add:1;     /* do not issue start on add */
 161         unsigned allow_restart:1; /* issue START_UNIT in error handler */
 162         unsigned manage_start_stop:1;   /* Let HLD (sd) manage start/stop */
 163         unsigned start_stop_pwr_cond:1; /* Set power cond. in START_STOP_UNIT */
 164         unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
 165         unsigned select_no_atn:1;
 166         unsigned fix_capacity:1;        /* READ_CAPACITY is too high by 1 */
 167         unsigned guess_capacity:1;      /* READ_CAPACITY might be too high by 1 */
 168         unsigned retry_hwerror:1;       /* Retry HARDWARE_ERROR */
 169         unsigned last_sector_bug:1;     /* do not use multisector accesses on
 170                                            SD_LAST_BUGGY_SECTORS */
 171         unsigned no_read_disc_info:1;   /* Avoid READ_DISC_INFO cmds */
 172         unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
 173         unsigned try_rc_10_first:1;     /* Try READ_CAPACACITY_10 first */
 174         unsigned is_visible:1;  /* is the device visible in sysfs */
 175         unsigned wce_default_on:1;      /* Cache is ON by default */
 176         unsigned no_dif:1;      /* T10 PI (DIF) should be disabled */
 177         unsigned broken_fua:1;          /* Don't set FUA bit */
 178         unsigned lun_in_cdb:1;          /* Store LUN bits in CDB[1] */
 179         unsigned synchronous_alua:1;    /* Synchronous ALUA commands */
 180
 181         atomic_t disk_events_disable_depth; /* disable depth for disk events */
 182
 183         DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
 184         DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
 185         struct list_head event_list;    /* asserted events */
 186         struct work_struct event_work;
 187
 188         unsigned int max_device_blocked; /* what device_blocked counts down from  */
 189 #define SCSI_DEFAULT_DEVICE_BLOCKED     3
 190
 191         atomic_t iorequest_cnt;
 192         atomic_t iodone_cnt;
 193         atomic_t ioerr_cnt;
 194
 195         struct device           sdev_gendev,
 196                                 sdev_dev;
 197
 198         struct execute_work     ew; /* used to get process context on put */
 199         struct work_struct      requeue_work;
 200
 201         struct scsi_device_handler *handler;
 202         void                    *handler_data;
 203
 204         unsigned char           access_state;
 205         enum scsi_device_state sdev_state;
 206         unsigned long           sdev_data[0];
 207 } __attribute__((aligned(sizeof(unsigned long))));
 208
 209 #define to_scsi_device(d)       \
 210         container_of(d, struct scsi_device, sdev_gendev)
 211 #define class_to_sdev(d)        \
 212         container_of(d, struct scsi_device, sdev_dev)
 213 #define transport_class_to_sdev(class_dev) \
 214         to_scsi_device(class_dev->parent)
 215
 216 #define sdev_dbg(sdev, fmt, a...) \
 217         dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)
 218
 219 /*
 220  * like scmd_printk, but the device name is passed in
 221  * as a string pointer
 222  */
 223 __printf(4, 5) void
 224 sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
 225                 const char *, ...);
 226
 227 #define sdev_printk(l, sdev, fmt, a...)                         \
 228         sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
 229
 230 __printf(3, 4) void
 231 scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
 232
 233 #define scmd_dbg(scmd, fmt, a...)                                          \
 234         do {                                                               \
 235                 if ((scmd)->request->rq_disk)                              \
 236                         sdev_dbg((scmd)->device, "[%s] " fmt,              \
 237                                  (scmd)->request->rq_disk->disk_name, ##a);\
 238                 else                                                       \
 239                         sdev_dbg((scmd)->device, fmt, ##a);                \
 240         } while (0)
 241
 242 enum scsi_target_state {
 243         STARGET_CREATED = 1,
 244         STARGET_RUNNING,
 245         STARGET_DEL,
 246 };
 247
 248 /*
 249  * scsi_target: representation of a scsi target, for now, this is only
 250  * used for single_lun devices. If no one has active IO to the target,
 251  * starget_sdev_user is NULL, else it points to the active sdev.
 252  */
 253 struct scsi_target {
 254         struct scsi_device      *starget_sdev_user;
 255         struct list_head        siblings;
 256         struct list_head        devices;
 257         struct device           dev;
 258         struct kref             reap_ref; /* last put renders target invisible */
 259         unsigned int            channel;
 260         unsigned int            id; /* target id ... replace
 261                                      * scsi_device.id eventually */
 262         unsigned int            create:1; /* signal that it needs to be added */
 263         unsigned int            single_lun:1;   /* Indicates we should only
 264                                                  * allow I/O to one of the luns
 265                                                  * for the device at a time. */
 266         unsigned int            pdt_1f_for_no_lun:1;    /* PDT = 0x1f
 267                                                  * means no lun present. */
 268         unsigned int            no_report_luns:1;       /* Don't use
 269                                                  * REPORT LUNS for scanning. */
 270         unsigned int            expecting_lun_change:1; /* A device has reported
 271                                                  * a 3F/0E UA, other devices on
 272                                                  * the same target will also. */
 273         /* commands actually active on LLD. */
 274         atomic_t                target_busy;
 275         atomic_t                target_blocked;
 276
 277         /*
 278          * LLDs should set this in the slave_alloc host template callout.
 279          * If set to zero then there is not limit.
 280          */
 281         unsigned int            can_queue;
 282         unsigned int            max_target_blocked;
 283 #define SCSI_DEFAULT_TARGET_BLOCKED     3
 284
 285         char                    scsi_level;
 286         enum scsi_target_state  state;
 287         void                    *hostdata; /* available to low-level driver */
 288         unsigned long           starget_data[0]; /* for the transport */
 289         /* starget_data must be the last element!!!! */
 290 } __attribute__((aligned(sizeof(unsigned long))));
 291
 292 #define to_scsi_target(d)       container_of(d, struct scsi_target, dev)
 293 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
 294 {
 295         return to_scsi_target(sdev->sdev_gendev.parent);
 296 }
 297 #define transport_class_to_starget(class_dev) \
 298         to_scsi_target(class_dev->parent)
 299
 300 #define starget_printk(prefix, starget, fmt, a...)      \
 301         dev_printk(prefix, &(starget)->dev, fmt, ##a)
 302
 303 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
 304                 uint, uint, u64, void *hostdata);
 305 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
 306                            uint target, u64 lun);
 307 extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
 308 extern void scsi_remove_device(struct scsi_device *);
 309 extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
 310 void scsi_attach_vpd(struct scsi_device *sdev);
 311
 312 extern int scsi_device_get(struct scsi_device *);
 313 extern void scsi_device_put(struct scsi_device *);
 314 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
 315                                               uint, uint, u64);
 316 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
 317                                                 uint, uint, u64);
 318 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
 319                                                         u64);
 320 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
 321                                                           u64);
 322 extern void starget_for_each_device(struct scsi_target *, void *,
 323                      void (*fn)(struct scsi_device *, void *));
 324 extern void __starget_for_each_device(struct scsi_target *, void *,
 325                                       void (*fn)(struct scsi_device *,
 326                                                  void *));
 327
 328 /* only exposed to implement shost_for_each_device */
 329 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
 330                                                   struct scsi_device *);
 331
 332 /**
 333  * shost_for_each_device - iterate over all devices of a host
 334  * @sdev: the &struct scsi_device to use as a cursor
 335  * @shost: the &struct scsi_host to iterate over
 336  *
 337  * Iterator that returns each device attached to @shost.  This loop
 338  * takes a reference on each device and releases it at the end.  If
 339  * you break out of the loop, you must call scsi_device_put(sdev).
 340  */
 341 #define shost_for_each_device(sdev, shost) \
 342         for ((sdev) = __scsi_iterate_devices((shost), NULL); \
 343              (sdev); \
 344              (sdev) = __scsi_iterate_devices((shost), (sdev)))
 345
 346 /**
 347  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
 348  * @sdev: the &struct scsi_device to use as a cursor
 349  * @shost: the &struct scsi_host to iterate over
 350  *
 351  * Iterator that returns each device attached to @shost.  It does _not_
 352  * take a reference on the scsi_device, so the whole loop must be
 353  * protected by shost->host_lock.
 354  *
 355  * Note: The only reason to use this is because you need to access the
 356  * device list in interrupt context.  Otherwise you really want to use
 357  * shost_for_each_device instead.
 358  */
 359 #define __shost_for_each_device(sdev, shost) \
 360         list_for_each_entry((sdev), &((shost)->__devices), siblings)
 361
 362 extern int scsi_change_queue_depth(struct scsi_device *, int);
 363 extern int scsi_track_queue_full(struct scsi_device *, int);
 364
 365 extern int scsi_set_medium_removal(struct scsi_device *, char);
 366
 367 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 368                            unsigned char *buffer, int len, int timeout,
 369                            int retries, struct scsi_mode_data *data,
 370                            struct scsi_sense_hdr *);
 371 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
 372                             int modepage, unsigned char *buffer, int len,
 373                             int timeout, int retries,
 374                             struct scsi_mode_data *data,
 375                             struct scsi_sense_hdr *);
 376 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
 377                                 int retries, struct scsi_sense_hdr *sshdr);
 378 extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
 379                              int buf_len);
 380 extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
 381                               unsigned int len, unsigned char opcode);
 382 extern int scsi_device_set_state(struct scsi_device *sdev,
 383                                  enum scsi_device_state state);
 384 extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
 385                                           gfp_t gfpflags);
 386 extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
 387 extern void sdev_evt_send_simple(struct scsi_device *sdev,
 388                           enum scsi_device_event evt_type, gfp_t gfpflags);
 389 extern int scsi_device_quiesce(struct scsi_device *sdev);
 390 extern void scsi_device_resume(struct scsi_device *sdev);
 391 extern void scsi_target_quiesce(struct scsi_target *);
 392 extern void scsi_target_resume(struct scsi_target *);
 393 extern void scsi_scan_target(struct device *parent, unsigned int channel,
 394                              unsigned int id, u64 lun, int rescan);
 395 extern void scsi_target_reap(struct scsi_target *);
 396 extern void scsi_target_block(struct device *);
 397 extern void scsi_target_unblock(struct device *, enum scsi_device_state);
 398 extern void scsi_remove_target(struct device *);
 399 extern const char *scsi_device_state_name(enum scsi_device_state);
 400 extern int scsi_is_sdev_device(const struct device *);
 401 extern int scsi_is_target_device(const struct device *);
 402 extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
 403 extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 404                         int data_direction, void *buffer, unsigned bufflen,
 405                         unsigned char *sense, int timeout, int retries,
 406                         u64 flags, int *resid);
 407 extern int scsi_execute_req_flags(struct scsi_device *sdev,
 408         const unsigned char *cmd, int data_direction, void *buffer,
 409         unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
 410         int retries, int *resid, u64 flags);
 411 static inline int scsi_execute_req(struct scsi_device *sdev,
 412         const unsigned char *cmd, int data_direction, void *buffer,
 413         unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
 414         int retries, int *resid)
 415 {
 416         return scsi_execute_req_flags(sdev, cmd, data_direction, buffer,
 417                 bufflen, sshdr, timeout, retries, resid, 0);
 418 }
 419 extern void sdev_disable_disk_events(struct scsi_device *sdev);
 420 extern void sdev_enable_disk_events(struct scsi_device *sdev);
 421 extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
 422 extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
 423
 424 #ifdef CONFIG_PM
 425 extern int scsi_autopm_get_device(struct scsi_device *);
 426 extern void scsi_autopm_put_device(struct scsi_device *);
 427 #else
 428 static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
 429 static inline void scsi_autopm_put_device(struct scsi_device *d) {}
 430 #endif /* CONFIG_PM */
 431
 432 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
 433 {
 434         return device_reprobe(&sdev->sdev_gendev);
 435 }
 436
 437 static inline unsigned int sdev_channel(struct scsi_device *sdev)
 438 {
 439         return sdev->channel;
 440 }
 441
 442 static inline unsigned int sdev_id(struct scsi_device *sdev)
 443 {
 444         return sdev->id;
 445 }
 446
 447 #define scmd_id(scmd) sdev_id((scmd)->device)
 448 #define scmd_channel(scmd) sdev_channel((scmd)->device)
 449
 450 /*
 451  * checks for positions of the SCSI state machine
 452  */
 453 static inline int scsi_device_online(struct scsi_device *sdev)
 454 {
 455         return (sdev->sdev_state != SDEV_OFFLINE &&
 456                 sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
 457                 sdev->sdev_state != SDEV_DEL);
 458 }
 459 static inline int scsi_device_blocked(struct scsi_device *sdev)
 460 {
 461         return sdev->sdev_state == SDEV_BLOCK ||
 462                 sdev->sdev_state == SDEV_CREATED_BLOCK;
 463 }
 464 static inline int scsi_device_created(struct scsi_device *sdev)
 465 {
 466         return sdev->sdev_state == SDEV_CREATED ||
 467                 sdev->sdev_state == SDEV_CREATED_BLOCK;
 468 }
 469
 470 /* accessor functions for the SCSI parameters */
 471 static inline int scsi_device_sync(struct scsi_device *sdev)
 472 {
 473         return sdev->sdtr;
 474 }
 475 static inline int scsi_device_wide(struct scsi_device *sdev)
 476 {
 477         return sdev->wdtr;
 478 }
 479 static inline int scsi_device_dt(struct scsi_device *sdev)
 480 {
 481         return sdev->ppr;
 482 }
 483 static inline int scsi_device_dt_only(struct scsi_device *sdev)
 484 {
 485         if (sdev->inquiry_len < 57)
 486                 return 0;
 487         return (sdev->inquiry[56] & 0x0c) == 0x04;
 488 }
 489 static inline int scsi_device_ius(struct scsi_device *sdev)
 490 {
 491         if (sdev->inquiry_len < 57)
 492                 return 0;
 493         return sdev->inquiry[56] & 0x01;
 494 }
 495 static inline int scsi_device_qas(struct scsi_device *sdev)
 496 {
 497         if (sdev->inquiry_len < 57)
 498                 return 0;
 499         return sdev->inquiry[56] & 0x02;
 500 }
 501 static inline int scsi_device_enclosure(struct scsi_device *sdev)
 502 {
 503         return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
 504 }
 505
 506 static inline int scsi_device_protection(struct scsi_device *sdev)
 507 {
 508         if (sdev->no_dif)
 509                 return 0;
 510
 511         return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
 512 }
 513
 514 static inline int scsi_device_tpgs(struct scsi_device *sdev)
 515 {
 516         return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
 517 }
 518
 519 /**
 520  * scsi_device_supports_vpd - test if a device supports VPD pages
 521  * @sdev: the &struct scsi_device to test
 522  *
 523  * If the 'try_vpd_pages' flag is set it takes precedence.
 524  * Otherwise we will assume VPD pages are supported if the
 525  * SCSI level is at least SPC-3 and 'skip_vpd_pages' is not set.
 526  */
 527 static inline int scsi_device_supports_vpd(struct scsi_device *sdev)
 528 {
 529         /* Attempt VPD inquiry if the device blacklist explicitly calls
 530          * for it.
 531          */
 532         if (sdev->try_vpd_pages)
 533                 return 1;
 534         /*
 535          * Although VPD inquiries can go to SCSI-2 type devices,
 536          * some USB ones crash on receiving them, and the pages
 537          * we currently ask for are for SPC-3 and beyond
 538          */
 539         if (sdev->scsi_level > SCSI_SPC_2 && !sdev->skip_vpd_pages)
 540                 return 1;
 541         return 0;
 542 }
 543
 544 #define MODULE_ALIAS_SCSI_DEVICE(type) \
 545         MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 546 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
 547
 548 #endif /* _SCSI_SCSI_DEVICE_H */