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