include/scsi/scsi_device.h

   1 #ifndef _SCSI_SCSI_DEVICE_H
   2 #define _SCSI_SCSI_DEVICE_H
   3
   4 #include <linux/device.h>
   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 <asm/atomic.h>
  11
  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_BLOCK,             /* Device blocked by scsi lld.  No
  46                                  * scsi commands from user or midlayer
  47                                  * should be issued to the scsi
  48                                  * lld. */
  49         SDEV_CREATED_BLOCK,     /* same as above but for created devices */
  50 };
  51
  52 enum scsi_device_event {
  53         SDEV_EVT_MEDIA_CHANGE   = 1,    /* media has changed */
  54
  55         SDEV_EVT_LAST           = SDEV_EVT_MEDIA_CHANGE,
  56         SDEV_EVT_MAXBITS        = SDEV_EVT_LAST + 1
  57 };
  58
  59 struct scsi_event {
  60         enum scsi_device_event  evt_type;
  61         struct list_head        node;
  62
  63         /* put union of data structures, for non-simple event types,
  64          * here
  65          */
  66 };
  67
  68 struct scsi_device {
  69         struct Scsi_Host *host;
  70         struct request_queue *request_queue;
  71
  72         /* the next two are protected by the host->host_lock */
  73         struct list_head    siblings;   /* list of all devices on this host */
  74         struct list_head    same_target_siblings; /* just the devices sharing same target id */
  75
  76         /* this is now protected by the request_queue->queue_lock */
  77         unsigned int device_busy;       /* commands actually active on
  78                                          * low-level. protected by queue_lock. */
  79         spinlock_t list_lock;
  80         struct list_head cmd_list;      /* queue of in use SCSI Command structures */
  81         struct list_head starved_entry;
  82         struct scsi_cmnd *current_cmnd; /* currently active command */
  83         unsigned short queue_depth;     /* How deep of a queue we want */
  84         unsigned short max_queue_depth; /* max queue depth */
  85         unsigned short last_queue_full_depth; /* These two are used by */
  86         unsigned short last_queue_full_count; /* scsi_track_queue_full() */
  87         unsigned long last_queue_full_time;     /* last queue full time */
  88         unsigned long queue_ramp_up_period;     /* ramp up period in jiffies */
  89 #define SCSI_DEFAULT_RAMP_UP_PERIOD     (120 * HZ)
  90
  91         unsigned long last_queue_ramp_up;       /* last queue ramp up time */
  92
  93         unsigned int id, lun, channel;
  94
  95         unsigned int manufacturer;      /* Manufacturer of device, for using
  96                                          * vendor-specific cmd's */
  97         unsigned sector_size;   /* size in bytes */
  98
  99         void *hostdata;         /* available to low-level driver */
 100         char type;
 101         char scsi_level;
 102         char inq_periph_qual;   /* PQ from INQUIRY data */
 103         unsigned char inquiry_len;      /* valid bytes in 'inquiry' */
 104         unsigned char * inquiry;        /* INQUIRY response data */
 105         const char * vendor;            /* [back_compat] point into 'inquiry' ... */
 106         const char * model;             /* ... after scan; point to static string */
 107         const char * rev;               /* ... "nullnullnullnull" before scan */
 108         unsigned char current_tag;      /* current tag */
 109         struct scsi_target      *sdev_target;   /* used only for single_lun */
 110
 111         unsigned int    sdev_bflags; /* black/white flags as also found in
 112                                  * scsi_devinfo.[hc]. For now used only to
 113                                  * pass settings from slave_alloc to scsi
 114                                  * core. */
 115         unsigned writeable:1;
 116         unsigned removable:1;
 117         unsigned changed:1;     /* Data invalid due to media change */
 118         unsigned busy:1;        /* Used to prevent races */
 119         unsigned lockable:1;    /* Able to prevent media removal */
 120         unsigned locked:1;      /* Media removal disabled */
 121         unsigned borken:1;      /* Tell the Seagate driver to be
 122                                  * painfully slow on this device */
 123         unsigned disconnect:1;  /* can disconnect */
 124         unsigned soft_reset:1;  /* Uses soft reset option */
 125         unsigned sdtr:1;        /* Device supports SDTR messages */
 126         unsigned wdtr:1;        /* Device supports WDTR messages */
 127         unsigned ppr:1;         /* Device supports PPR messages */
 128         unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
 129         unsigned simple_tags:1; /* simple queue tag messages are enabled */
 130         unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
 131         unsigned was_reset:1;   /* There was a bus reset on the bus for
 132                                  * this device */
 133         unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
 134                                      * because we did a bus reset. */
 135         unsigned use_10_for_rw:1; /* first try 10-byte read / write */
 136         unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
 137         unsigned skip_ms_page_8:1;      /* do not use MODE SENSE page 0x08 */
 138         unsigned skip_ms_page_3f:1;     /* do not use MODE SENSE page 0x3f */
 139         unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
 140         unsigned no_start_on_add:1;     /* do not issue start on add */
 141         unsigned allow_restart:1; /* issue START_UNIT in error handler */
 142         unsigned manage_start_stop:1;   /* Let HLD (sd) manage start/stop */
 143         unsigned start_stop_pwr_cond:1; /* Set power cond. in START_STOP_UNIT */
 144         unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
 145         unsigned select_no_atn:1;
 146         unsigned fix_capacity:1;        /* READ_CAPACITY is too high by 1 */
 147         unsigned guess_capacity:1;      /* READ_CAPACITY might be too high by 1 */
 148         unsigned retry_hwerror:1;       /* Retry HARDWARE_ERROR */
 149         unsigned last_sector_bug:1;     /* do not use multisector accesses on
 150                                            SD_LAST_BUGGY_SECTORS */
 151         unsigned is_visible:1;  /* is the device visible in sysfs */
 152
 153         DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
 154         struct list_head event_list;    /* asserted events */
 155         struct work_struct event_work;
 156
 157         unsigned int device_blocked;    /* Device returned QUEUE_FULL. */
 158
 159         unsigned int max_device_blocked; /* what device_blocked counts down from  */
 160 #define SCSI_DEFAULT_DEVICE_BLOCKED     3
 161
 162         atomic_t iorequest_cnt;
 163         atomic_t iodone_cnt;
 164         atomic_t ioerr_cnt;
 165
 166         struct device           sdev_gendev,
 167                                 sdev_dev;
 168
 169         struct execute_work     ew; /* used to get process context on put */
 170
 171         struct scsi_dh_data     *scsi_dh_data;
 172         enum scsi_device_state sdev_state;
 173         unsigned long           sdev_data[0];
 174 } __attribute__((aligned(sizeof(unsigned long))));
 175
 176 struct scsi_dh_devlist {
 177         char *vendor;
 178         char *model;
 179 };
 180
 181 typedef void (*activate_complete)(void *, int);
 182 struct scsi_device_handler {
 183         /* Used by the infrastructure */
 184         struct list_head list; /* list of scsi_device_handlers */
 185
 186         /* Filled by the hardware handler */
 187         struct module *module;
 188         const char *name;
 189         const struct scsi_dh_devlist *devlist;
 190         int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *);
 191         int (*attach)(struct scsi_device *);
 192         void (*detach)(struct scsi_device *);
 193         int (*activate)(struct scsi_device *, activate_complete, void *);
 194         int (*prep_fn)(struct scsi_device *, struct request *);
 195         int (*set_params)(struct scsi_device *, const char *);
 196 };
 197
 198 struct scsi_dh_data {
 199         struct scsi_device_handler *scsi_dh;
 200         struct scsi_device *sdev;
 201         struct kref kref;
 202         char buf[0];
 203 };
 204
 205 #define to_scsi_device(d)       \
 206         container_of(d, struct scsi_device, sdev_gendev)
 207 #define class_to_sdev(d)        \
 208         container_of(d, struct scsi_device, sdev_dev)
 209 #define transport_class_to_sdev(class_dev) \
 210         to_scsi_device(class_dev->parent)
 211
 212 #define sdev_printk(prefix, sdev, fmt, a...)    \
 213         dev_printk(prefix, &(sdev)->sdev_gendev, fmt, ##a)
 214
 215 #define scmd_printk(prefix, scmd, fmt, a...)                            \
 216         (scmd)->request->rq_disk ?                                      \
 217         sdev_printk(prefix, (scmd)->device, "[%s] " fmt,                \
 218                     (scmd)->request->rq_disk->disk_name, ##a) :         \
 219         sdev_printk(prefix, (scmd)->device, fmt, ##a)
 220
 221 enum scsi_target_state {
 222         STARGET_CREATED = 1,
 223         STARGET_RUNNING,
 224         STARGET_DEL,
 225 };
 226
 227 /*
 228  * scsi_target: representation of a scsi target, for now, this is only
 229  * used for single_lun devices. If no one has active IO to the target,
 230  * starget_sdev_user is NULL, else it points to the active sdev.
 231  */
 232 struct scsi_target {
 233         struct scsi_device      *starget_sdev_user;
 234         struct list_head        siblings;
 235         struct list_head        devices;
 236         struct device           dev;
 237         unsigned int            reap_ref; /* protected by the host lock */
 238         unsigned int            channel;
 239         unsigned int            id; /* target id ... replace
 240                                      * scsi_device.id eventually */
 241         unsigned int            create:1; /* signal that it needs to be added */
 242         unsigned int            single_lun:1;   /* Indicates we should only
 243                                                  * allow I/O to one of the luns
 244                                                  * for the device at a time. */
 245         unsigned int            pdt_1f_for_no_lun;      /* PDT = 0x1f */
 246                                                 /* means no lun present */
 247         /* commands actually active on LLD. protected by host lock. */
 248         unsigned int            target_busy;
 249         /*
 250          * LLDs should set this in the slave_alloc host template callout.
 251          * If set to zero then there is not limit.
 252          */
 253         unsigned int            can_queue;
 254         unsigned int            target_blocked;
 255         unsigned int            max_target_blocked;
 256 #define SCSI_DEFAULT_TARGET_BLOCKED     3
 257
 258         char                    scsi_level;
 259         struct execute_work     ew;
 260         enum scsi_target_state  state;
 261         void                    *hostdata; /* available to low-level driver */
 262         unsigned long           starget_data[0]; /* for the transport */
 263         /* starget_data must be the last element!!!! */
 264 } __attribute__((aligned(sizeof(unsigned long))));
 265
 266 #define to_scsi_target(d)       container_of(d, struct scsi_target, dev)
 267 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
 268 {
 269         return to_scsi_target(sdev->sdev_gendev.parent);
 270 }
 271 #define transport_class_to_starget(class_dev) \
 272         to_scsi_target(class_dev->parent)
 273
 274 #define starget_printk(prefix, starget, fmt, a...)      \
 275         dev_printk(prefix, &(starget)->dev, fmt, ##a)
 276
 277 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
 278                 uint, uint, uint, void *hostdata);
 279 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
 280                            uint target, uint lun);
 281 extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
 282 extern void scsi_remove_device(struct scsi_device *);
 283 extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
 284
 285 extern int scsi_device_get(struct scsi_device *);
 286 extern void scsi_device_put(struct scsi_device *);
 287 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
 288                                               uint, uint, uint);
 289 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
 290                                                 uint, uint, uint);
 291 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
 292                                                         uint);
 293 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
 294                                                           uint);
 295 extern void starget_for_each_device(struct scsi_target *, void *,
 296                      void (*fn)(struct scsi_device *, void *));
 297 extern void __starget_for_each_device(struct scsi_target *, void *,
 298                                       void (*fn)(struct scsi_device *,
 299                                                  void *));
 300
 301 /* only exposed to implement shost_for_each_device */
 302 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
 303                                                   struct scsi_device *);
 304
 305 /**
 306  * shost_for_each_device - iterate over all devices of a host
 307  * @sdev: the &struct scsi_device to use as a cursor
 308  * @shost: the &struct scsi_host to iterate over
 309  *
 310  * Iterator that returns each device attached to @shost.  This loop
 311  * takes a reference on each device and releases it at the end.  If
 312  * you break out of the loop, you must call scsi_device_put(sdev).
 313  */
 314 #define shost_for_each_device(sdev, shost) \
 315         for ((sdev) = __scsi_iterate_devices((shost), NULL); \
 316              (sdev); \
 317              (sdev) = __scsi_iterate_devices((shost), (sdev)))
 318
 319 /**
 320  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
 321  * @sdev: the &struct scsi_device to use as a cursor
 322  * @shost: the &struct scsi_host to iterate over
 323  *
 324  * Iterator that returns each device attached to @shost.  It does _not_
 325  * take a reference on the scsi_device, so the whole loop must be
 326  * protected by shost->host_lock.
 327  *
 328  * Note: The only reason to use this is because you need to access the
 329  * device list in interrupt context.  Otherwise you really want to use
 330  * shost_for_each_device instead.
 331  */
 332 #define __shost_for_each_device(sdev, shost) \
 333         list_for_each_entry((sdev), &((shost)->__devices), siblings)
 334
 335 extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
 336 extern int scsi_track_queue_full(struct scsi_device *, int);
 337
 338 extern int scsi_set_medium_removal(struct scsi_device *, char);
 339
 340 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 341                            unsigned char *buffer, int len, int timeout,
 342                            int retries, struct scsi_mode_data *data,
 343                            struct scsi_sense_hdr *);
 344 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
 345                             int modepage, unsigned char *buffer, int len,
 346                             int timeout, int retries,
 347                             struct scsi_mode_data *data,
 348                             struct scsi_sense_hdr *);
 349 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
 350                                 int retries, struct scsi_sense_hdr *sshdr);
 351 extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
 352                              int buf_len);
 353 extern int scsi_device_set_state(struct scsi_device *sdev,
 354                                  enum scsi_device_state state);
 355 extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
 356                                           gfp_t gfpflags);
 357 extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
 358 extern void sdev_evt_send_simple(struct scsi_device *sdev,
 359                           enum scsi_device_event evt_type, gfp_t gfpflags);
 360 extern int scsi_device_quiesce(struct scsi_device *sdev);
 361 extern void scsi_device_resume(struct scsi_device *sdev);
 362 extern void scsi_target_quiesce(struct scsi_target *);
 363 extern void scsi_target_resume(struct scsi_target *);
 364 extern void scsi_scan_target(struct device *parent, unsigned int channel,
 365                              unsigned int id, unsigned int lun, int rescan);
 366 extern void scsi_target_reap(struct scsi_target *);
 367 extern void scsi_target_block(struct device *);
 368 extern void scsi_target_unblock(struct device *);
 369 extern void scsi_remove_target(struct device *);
 370 extern void int_to_scsilun(unsigned int, struct scsi_lun *);
 371 extern int scsilun_to_int(struct scsi_lun *);
 372 extern const char *scsi_device_state_name(enum scsi_device_state);
 373 extern int scsi_is_sdev_device(const struct device *);
 374 extern int scsi_is_target_device(const struct device *);
 375 extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 376                         int data_direction, void *buffer, unsigned bufflen,
 377                         unsigned char *sense, int timeout, int retries,
 378                         int flag, int *resid);
 379 extern int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
 380                             int data_direction, void *buffer, unsigned bufflen,
 381                             struct scsi_sense_hdr *, int timeout, int retries,
 382                             int *resid);
 383
 384 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
 385 {
 386         return device_reprobe(&sdev->sdev_gendev);
 387 }
 388
 389 static inline unsigned int sdev_channel(struct scsi_device *sdev)
 390 {
 391         return sdev->channel;
 392 }
 393
 394 static inline unsigned int sdev_id(struct scsi_device *sdev)
 395 {
 396         return sdev->id;
 397 }
 398
 399 #define scmd_id(scmd) sdev_id((scmd)->device)
 400 #define scmd_channel(scmd) sdev_channel((scmd)->device)
 401
 402 /*
 403  * checks for positions of the SCSI state machine
 404  */
 405 static inline int scsi_device_online(struct scsi_device *sdev)
 406 {
 407         return (sdev->sdev_state != SDEV_OFFLINE &&
 408                 sdev->sdev_state != SDEV_DEL);
 409 }
 410 static inline int scsi_device_blocked(struct scsi_device *sdev)
 411 {
 412         return sdev->sdev_state == SDEV_BLOCK ||
 413                 sdev->sdev_state == SDEV_CREATED_BLOCK;
 414 }
 415 static inline int scsi_device_created(struct scsi_device *sdev)
 416 {
 417         return sdev->sdev_state == SDEV_CREATED ||
 418                 sdev->sdev_state == SDEV_CREATED_BLOCK;
 419 }
 420
 421 /* accessor functions for the SCSI parameters */
 422 static inline int scsi_device_sync(struct scsi_device *sdev)
 423 {
 424         return sdev->sdtr;
 425 }
 426 static inline int scsi_device_wide(struct scsi_device *sdev)
 427 {
 428         return sdev->wdtr;
 429 }
 430 static inline int scsi_device_dt(struct scsi_device *sdev)
 431 {
 432         return sdev->ppr;
 433 }
 434 static inline int scsi_device_dt_only(struct scsi_device *sdev)
 435 {
 436         if (sdev->inquiry_len < 57)
 437                 return 0;
 438         return (sdev->inquiry[56] & 0x0c) == 0x04;
 439 }
 440 static inline int scsi_device_ius(struct scsi_device *sdev)
 441 {
 442         if (sdev->inquiry_len < 57)
 443                 return 0;
 444         return sdev->inquiry[56] & 0x01;
 445 }
 446 static inline int scsi_device_qas(struct scsi_device *sdev)
 447 {
 448         if (sdev->inquiry_len < 57)
 449                 return 0;
 450         return sdev->inquiry[56] & 0x02;
 451 }
 452 static inline int scsi_device_enclosure(struct scsi_device *sdev)
 453 {
 454         return sdev->inquiry[6] & (1<<6);
 455 }
 456
 457 static inline int scsi_device_protection(struct scsi_device *sdev)
 458 {
 459         return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
 460 }
 461
 462 #define MODULE_ALIAS_SCSI_DEVICE(type) \
 463         MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 464 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
 465
 466 #endif /* _SCSI_SCSI_DEVICE_H */