LXR linux/include/scsi/scsi

   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
  11struct device;
  12struct request_queue;
  13struct scsi_cmnd;
  14struct scsi_lun;
  15struct scsi_sense_hdr;
  16
  17struct 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 */
  31enum 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
  53enum 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
  68struct 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
  77struct 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
 224sdev_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
 231scmd_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
 242enum 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 */
 253struct 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)
 293static 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
 303extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
 304                uint, uint, u64, void *hostdata);
 305extern int scsi_add_device(struct Scsi_Host *host, uint channel,
 306                           uint target, u64 lun);
 307extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
 308extern void scsi_remove_device(struct scsi_device *);
 309extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
 310void scsi_attach_vpd(struct scsi_device *sdev);
 311
 312extern int scsi_device_get(struct scsi_device *);
 313extern void scsi_device_put(struct scsi_device *);
 314extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
 315                                              uint, uint, u64);
 316extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
 317                                                uint, uint, u64);
 318extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
 319                                                        u64);
 320extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
 321                                                          u64);
 322extern void starget_for_each_device(struct scsi_target *, void *,
 323                     void (*fn)(struct scsi_device *, void *));
 324extern 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 */
 329extern 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
 362extern int scsi_change_queue_depth(struct scsi_device *, int);
 363extern int scsi_track_queue_full(struct scsi_device *, int);
 364
 365extern int scsi_set_medium_removal(struct scsi_device *, char);
 366
 367extern 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 *);
 371extern 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 *);
 376extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
 377                                int retries, struct scsi_sense_hdr *sshdr);
 378extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
 379                             int buf_len);
 380extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
 381                              unsigned int len, unsigned char opcode);
 382extern int scsi_device_set_state(struct scsi_device *sdev,
 383                                 enum scsi_device_state state);
 384extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
 385                                          gfp_t gfpflags);
 386extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
 387extern void sdev_evt_send_simple(struct scsi_device *sdev,
 388                          enum scsi_device_event evt_type, gfp_t gfpflags);
 389extern int scsi_device_quiesce(struct scsi_device *sdev);
 390extern void scsi_device_resume(struct scsi_device *sdev);
 391extern void scsi_target_quiesce(struct scsi_target *);
 392extern void scsi_target_resume(struct scsi_target *);
 393extern void scsi_scan_target(struct device *parent, unsigned int channel,
 394                             unsigned int id, u64 lun, int rescan);
 395extern void scsi_target_reap(struct scsi_target *);
 396extern void scsi_target_block(struct device *);
 397extern void scsi_target_unblock(struct device *, enum scsi_device_state);
 398extern void scsi_remove_target(struct device *);
 399extern const char *scsi_device_state_name(enum scsi_device_state);
 400extern int scsi_is_sdev_device(const struct device *);
 401extern int scsi_is_target_device(const struct device *);
 402extern void scsi_sanitize_inquiry_string(unsigned char *s, int len);
 403extern 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);
 407extern 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);
 411static 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}
 419extern void sdev_disable_disk_events(struct scsi_device *sdev);
 420extern void sdev_enable_disk_events(struct scsi_device *sdev);
 421extern int scsi_vpd_lun_id(struct scsi_device *, char *, size_t);
 422extern int scsi_vpd_tpg_id(struct scsi_device *, int *);
 423
 424#ifdef CONFIG_PM
 425extern int scsi_autopm_get_device(struct scsi_device *);
 426extern void scsi_autopm_put_device(struct scsi_device *);
 427#else
 428static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
 429static inline void scsi_autopm_put_device(struct scsi_device *d) {}
 430#endif /* CONFIG_PM */
 431
 432static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
 433{
 434        return device_reprobe(&sdev->sdev_gendev);
 435}
 436
 437static inline unsigned int sdev_channel(struct scsi_device *sdev)
 438{
 439        return sdev->channel;
 440}
 441
 442static 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 */
 453static 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}
 459static 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}
 464static 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 */
 471static inline int scsi_device_sync(struct scsi_device *sdev)
 472{
 473        return sdev->sdtr;
 474}
 475static inline int scsi_device_wide(struct scsi_device *sdev)
 476{
 477        return sdev->wdtr;
 478}
 479static inline int scsi_device_dt(struct scsi_device *sdev)
 480{
 481        return sdev->ppr;
 482}
 483static 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}
 489static 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}
 495static 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}
 501static inline int scsi_device_enclosure(struct scsi_device *sdev)
 502{
 503        return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
 504}
 505
 506static 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
 514static 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 */
 527static 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 */
 549