LXR linux/include/scsi/scsi

   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
  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_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
  52enum 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
  59struct 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
  68struct 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        unsigned is_visible:1;  /* is the device visible in sysfs */
 149
 150        DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
 151        struct list_head event_list;    /* asserted events */
 152        struct work_struct event_work;
 153
 154        unsigned int device_blocked;    /* Device returned QUEUE_FULL. */
 155
 156        unsigned int max_device_blocked; /* what device_blocked counts down from  */
 157#define SCSI_DEFAULT_DEVICE_BLOCKED     3
 158
 159        atomic_t iorequest_cnt;
 160        atomic_t iodone_cnt;
 161        atomic_t ioerr_cnt;
 162
 163        struct device           sdev_gendev,
 164                                sdev_dev;
 165
 166        struct execute_work     ew; /* used to get process context on put */
 167
 168        struct scsi_dh_data     *scsi_dh_data;
 169        enum scsi_device_state sdev_state;
 170        unsigned long           sdev_data[0];
 171} __attribute__((aligned(sizeof(unsigned long))));
 172
 173struct scsi_dh_devlist {
 174        char *vendor;
 175        char *model;
 176};
 177
 178struct scsi_device_handler {
 179        /* Used by the infrastructure */
 180        struct list_head list; /* list of scsi_device_handlers */
 181
 182        /* Filled by the hardware handler */
 183        struct module *module;
 184        const char *name;
 185        const struct scsi_dh_devlist *devlist;
 186        int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *);
 187        int (*attach)(struct scsi_device *);
 188        void (*detach)(struct scsi_device *);
 189        int (*activate)(struct scsi_device *);
 190        int (*prep_fn)(struct scsi_device *, struct request *);
 191        int (*set_params)(struct scsi_device *, const char *);
 192};
 193
 194struct scsi_dh_data {
 195        struct scsi_device_handler *scsi_dh;
 196        struct scsi_device *sdev;
 197        struct kref kref;
 198        char buf[0];
 199};
 200
 201#define to_scsi_device(d)       \
 202        container_of(d, struct scsi_device, sdev_gendev)
 203#define class_to_sdev(d)        \
 204        container_of(d, struct scsi_device, sdev_dev)
 205#define transport_class_to_sdev(class_dev) \
 206        to_scsi_device(class_dev->parent)
 207
 208#define sdev_printk(prefix, sdev, fmt, a...)    \
 209        dev_printk(prefix, &(sdev)->sdev_gendev, fmt, ##a)
 210
 211#define scmd_printk(prefix, scmd, fmt, a...)                            \
 212        (scmd)->request->rq_disk ?                                      \
 213        sdev_printk(prefix, (scmd)->device, "[%s] " fmt,                \
 214                    (scmd)->request->rq_disk->disk_name, ##a) :         \
 215        sdev_printk(prefix, (scmd)->device, fmt, ##a)
 216
 217enum scsi_target_state {
 218        STARGET_CREATED = 1,
 219        STARGET_RUNNING,
 220        STARGET_DEL,
 221};
 222
 223/*
 224 * scsi_target: representation of a scsi target, for now, this is only
 225 * used for single_lun devices. If no one has active IO to the target,
 226 * starget_sdev_user is NULL, else it points to the active sdev.
 227 */
 228struct scsi_target {
 229        struct scsi_device      *starget_sdev_user;
 230        struct list_head        siblings;
 231        struct list_head        devices;
 232        struct device           dev;
 233        unsigned int            reap_ref; /* protected by the host lock */
 234        unsigned int            channel;
 235        unsigned int            id; /* target id ... replace
 236                                     * scsi_device.id eventually */
 237        unsigned int            create:1; /* signal that it needs to be added */
 238        unsigned int            single_lun:1;   /* Indicates we should only
 239                                                 * allow I/O to one of the luns
 240                                                 * for the device at a time. */
 241        unsigned int            pdt_1f_for_no_lun;      /* PDT = 0x1f */
 242                                                /* means no lun present */
 243        /* commands actually active on LLD. protected by host lock. */
 244        unsigned int            target_busy;
 245        /*
 246         * LLDs should set this in the slave_alloc host template callout.
 247         * If set to zero then there is not limit.
 248         */
 249        unsigned int            can_queue;
 250        unsigned int            target_blocked;
 251        unsigned int            max_target_blocked;
 252#define SCSI_DEFAULT_TARGET_BLOCKED     3
 253
 254        char                    scsi_level;
 255        struct execute_work     ew;
 256        enum scsi_target_state  state;
 257        void                    *hostdata; /* available to low-level driver */
 258        unsigned long           starget_data[0]; /* for the transport */
 259        /* starget_data must be the last element!!!! */
 260} __attribute__((aligned(sizeof(unsigned long))));
 261
 262#define to_scsi_target(d)       container_of(d, struct scsi_target, dev)
 263static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
 264{
 265        return to_scsi_target(sdev->sdev_gendev.parent);
 266}
 267#define transport_class_to_starget(class_dev) \
 268        to_scsi_target(class_dev->parent)
 269
 270#define starget_printk(prefix, starget, fmt, a...)      \
 271        dev_printk(prefix, &(starget)->dev, fmt, ##a)
 272
 273extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
 274                uint, uint, uint, void *hostdata);
 275extern int scsi_add_device(struct Scsi_Host *host, uint channel,
 276                           uint target, uint lun);
 277extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
 278extern void scsi_remove_device(struct scsi_device *);
 279extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
 280
 281extern int scsi_device_get(struct scsi_device *);
 282extern void scsi_device_put(struct scsi_device *);
 283extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
 284                                              uint, uint, uint);
 285extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
 286                                                uint, uint, uint);
 287extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
 288                                                        uint);
 289extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
 290                                                          uint);
 291extern void starget_for_each_device(struct scsi_target *, void *,
 292                     void (*fn)(struct scsi_device *, void *));
 293extern void __starget_for_each_device(struct scsi_target *, void *,
 294                                      void (*fn)(struct scsi_device *,
 295                                                 void *));
 296
 297/* only exposed to implement shost_for_each_device */
 298extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
 299                                                  struct scsi_device *);
 300
 301/**
 302 * shost_for_each_device - iterate over all devices of a host
 303 * @sdev: the &struct scsi_device to use as a cursor
 304 * @shost: the &struct scsi_host to iterate over
 305 *
 306 * Iterator that returns each device attached to @shost.  This loop
 307 * takes a reference on each device and releases it at the end.  If
 308 * you break out of the loop, you must call scsi_device_put(sdev).
 309 */
 310#define shost_for_each_device(sdev, shost) \
 311        for ((sdev) = __scsi_iterate_devices((shost), NULL); \
 312             (sdev); \
 313             (sdev) = __scsi_iterate_devices((shost), (sdev)))
 314
 315/**
 316 * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
 317 * @sdev: the &struct scsi_device to use as a cursor
 318 * @shost: the &struct scsi_host to iterate over
 319 *
 320 * Iterator that returns each device attached to @shost.  It does _not_
 321 * take a reference on the scsi_device, so the whole loop must be
 322 * protected by shost->host_lock.
 323 *
 324 * Note: The only reason to use this is because you need to access the
 325 * device list in interrupt context.  Otherwise you really want to use
 326 * shost_for_each_device instead.
 327 */
 328#define __shost_for_each_device(sdev, shost) \
 329        list_for_each_entry((sdev), &((shost)->__devices), siblings)
 330
 331extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
 332extern int scsi_track_queue_full(struct scsi_device *, int);
 333
 334extern int scsi_set_medium_removal(struct scsi_device *, char);
 335
 336extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 337                           unsigned char *buffer, int len, int timeout,
 338                           int retries, struct scsi_mode_data *data,
 339                           struct scsi_sense_hdr *);
 340extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
 341                            int modepage, unsigned char *buffer, int len,
 342                            int timeout, int retries,
 343                            struct scsi_mode_data *data,
 344                            struct scsi_sense_hdr *);
 345extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
 346                                int retries, struct scsi_sense_hdr *sshdr);
 347extern unsigned char *scsi_get_vpd_page(struct scsi_device *, u8 page);
 348extern int scsi_device_set_state(struct scsi_device *sdev,
 349                                 enum scsi_device_state state);
 350extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
 351                                          gfp_t gfpflags);
 352extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
 353extern void sdev_evt_send_simple(struct scsi_device *sdev,
 354                          enum scsi_device_event evt_type, gfp_t gfpflags);
 355extern int scsi_device_quiesce(struct scsi_device *sdev);
 356extern void scsi_device_resume(struct scsi_device *sdev);
 357extern void scsi_target_quiesce(struct scsi_target *);
 358extern void scsi_target_resume(struct scsi_target *);
 359extern void scsi_scan_target(struct device *parent, unsigned int channel,
 360                             unsigned int id, unsigned int lun, int rescan);
 361extern void scsi_target_reap(struct scsi_target *);
 362extern void scsi_target_block(struct device *);
 363extern void scsi_target_unblock(struct device *);
 364extern void scsi_remove_target(struct device *);
 365extern void int_to_scsilun(unsigned int, struct scsi_lun *);
 366extern int scsilun_to_int(struct scsi_lun *);
 367extern const char *scsi_device_state_name(enum scsi_device_state);
 368extern int scsi_is_sdev_device(const struct device *);
 369extern int scsi_is_target_device(const struct device *);
 370extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 371                        int data_direction, void *buffer, unsigned bufflen,
 372                        unsigned char *sense, int timeout, int retries,
 373                        int flag, int *resid);
 374extern int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
 375                            int data_direction, void *buffer, unsigned bufflen,
 376                            struct scsi_sense_hdr *, int timeout, int retries,
 377                            int *resid);
 378
 379static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
 380{
 381        return device_reprobe(&sdev->sdev_gendev);
 382}
 383
 384static inline unsigned int sdev_channel(struct scsi_device *sdev)
 385{
 386        return sdev->channel;
 387}
 388
 389static inline unsigned int sdev_id(struct scsi_device *sdev)
 390{
 391        return sdev->id;
 392}
 393
 394#define scmd_id(scmd) sdev_id((scmd)->device)
 395#define scmd_channel(scmd) sdev_channel((scmd)->device)
 396
 397/*
 398 * checks for positions of the SCSI state machine
 399 */
 400static inline int scsi_device_online(struct scsi_device *sdev)
 401{
 402        return (sdev->sdev_state != SDEV_OFFLINE &&
 403                sdev->sdev_state != SDEV_DEL);
 404}
 405static inline int scsi_device_blocked(struct scsi_device *sdev)
 406{
 407        return sdev->sdev_state == SDEV_BLOCK ||
 408                sdev->sdev_state == SDEV_CREATED_BLOCK;
 409}
 410static inline int scsi_device_created(struct scsi_device *sdev)
 411{
 412        return sdev->sdev_state == SDEV_CREATED ||
 413                sdev->sdev_state == SDEV_CREATED_BLOCK;
 414}
 415
 416/* accessor functions for the SCSI parameters */
 417static inline int scsi_device_sync(struct scsi_device *sdev)
 418{
 419        return sdev->sdtr;
 420}
 421static inline int scsi_device_wide(struct scsi_device *sdev)
 422{
 423        return sdev->wdtr;
 424}
 425static inline int scsi_device_dt(struct scsi_device *sdev)
 426{
 427        return sdev->ppr;
 428}
 429static inline int scsi_device_dt_only(struct scsi_device *sdev)
 430{
 431        if (sdev->inquiry_len < 57)
 432                return 0;
 433        return (sdev->inquiry[56] & 0x0c) == 0x04;
 434}
 435static inline int scsi_device_ius(struct scsi_device *sdev)
 436{
 437        if (sdev->inquiry_len < 57)
 438                return 0;
 439        return sdev->inquiry[56] & 0x01;
 440}
 441static inline int scsi_device_qas(struct scsi_device *sdev)
 442{
 443        if (sdev->inquiry_len < 57)
 444                return 0;
 445        return sdev->inquiry[56] & 0x02;
 446}
 447static inline int scsi_device_enclosure(struct scsi_device *sdev)
 448{
 449        return sdev->inquiry[6] & (1<<6);
 450}
 451
 452static inline int scsi_device_protection(struct scsi_device *sdev)
 453{
 454        return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
 455}
 456
 457#define MODULE_ALIAS_SCSI_DEVICE(type) \
 458        MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 459#define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
 460
 461#endif /* _SCSI_SCSI_DEVICE_H */
 462