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 <asm/atomic.h>
  10
  11 struct request_queue;
  12 struct scsi_cmnd;
  13 struct scsi_lun;
  14 struct scsi_sense_hdr;
  15
  16 struct scsi_mode_data {
  17         __u32   length;
  18         __u16   block_descriptor_length;
  19         __u8    medium_type;
  20         __u8    device_specific;
  21         __u8    header_length;
  22         __u8    longlba:1;
  23 };
  24
  25 /*
  26  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
  27  * (for the ascii descriptions) and the state model enforcer:
  28  * scsi_lib:scsi_device_set_state().
  29  */
  30 enum scsi_device_state {
  31         SDEV_CREATED = 1,       /* device created but not added to sysfs
  32                                  * Only internal commands allowed (for inq) */
  33         SDEV_RUNNING,           /* device properly configured
  34                                  * All commands allowed */
  35         SDEV_CANCEL,            /* beginning to delete device
  36                                  * Only error handler commands allowed */
  37         SDEV_DEL,               /* device deleted
  38                                  * no commands allowed */
  39         SDEV_QUIESCE,           /* Device quiescent.  No block commands
  40                                  * will be accepted, only specials (which
  41                                  * originate in the mid-layer) */
  42         SDEV_OFFLINE,           /* Device offlined (by error handling or
  43                                  * user request */
  44         SDEV_BLOCK,             /* Device blocked by scsi lld.  No scsi
  45                                  * commands from user or midlayer should be issued
  46                                  * to the scsi lld. */
  47 };
  48
  49 struct scsi_device {
  50         struct Scsi_Host *host;
  51         struct request_queue *request_queue;
  52
  53         /* the next two are protected by the host->host_lock */
  54         struct list_head    siblings;   /* list of all devices on this host */
  55         struct list_head    same_target_siblings; /* just the devices sharing same target id */
  56
  57         /* this is now protected by the request_queue->queue_lock */
  58         unsigned int device_busy;       /* commands actually active on
  59                                          * low-level. protected by queue_lock. */
  60         spinlock_t list_lock;
  61         struct list_head cmd_list;      /* queue of in use SCSI Command structures */
  62         struct list_head starved_entry;
  63         struct scsi_cmnd *current_cmnd; /* currently active command */
  64         unsigned short queue_depth;     /* How deep of a queue we want */
  65         unsigned short last_queue_full_depth; /* These two are used by */
  66         unsigned short last_queue_full_count; /* scsi_track_queue_full() */
  67         unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
  68                                            jiffie count on our counter, they
  69                                            could all be from the same event. */
  70
  71         unsigned int id, lun, channel;
  72
  73         unsigned int manufacturer;      /* Manufacturer of device, for using
  74                                          * vendor-specific cmd's */
  75         unsigned sector_size;   /* size in bytes */
  76
  77         void *hostdata;         /* available to low-level driver */
  78         char type;
  79         char scsi_level;
  80         char inq_periph_qual;   /* PQ from INQUIRY data */
  81         unsigned char inquiry_len;      /* valid bytes in 'inquiry' */
  82         unsigned char * inquiry;        /* INQUIRY response data */
  83         const char * vendor;            /* [back_compat] point into 'inquiry' ... */
  84         const char * model;             /* ... after scan; point to static string */
  85         const char * rev;               /* ... "nullnullnullnull" before scan */
  86         unsigned char current_tag;      /* current tag */
  87         struct scsi_target      *sdev_target;   /* used only for single_lun */
  88
  89         unsigned int    sdev_bflags; /* black/white flags as also found in
  90                                  * scsi_devinfo.[hc]. For now used only to
  91                                  * pass settings from slave_alloc to scsi
  92                                  * core. */
  93         unsigned writeable:1;
  94         unsigned removable:1;
  95         unsigned changed:1;     /* Data invalid due to media change */
  96         unsigned busy:1;        /* Used to prevent races */
  97         unsigned lockable:1;    /* Able to prevent media removal */
  98         unsigned locked:1;      /* Media removal disabled */
  99         unsigned borken:1;      /* Tell the Seagate driver to be
 100                                  * painfully slow on this device */
 101         unsigned disconnect:1;  /* can disconnect */
 102         unsigned soft_reset:1;  /* Uses soft reset option */
 103         unsigned sdtr:1;        /* Device supports SDTR messages */
 104         unsigned wdtr:1;        /* Device supports WDTR messages */
 105         unsigned ppr:1;         /* Device supports PPR messages */
 106         unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
 107         unsigned simple_tags:1; /* simple queue tag messages are enabled */
 108         unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
 109         unsigned single_lun:1;  /* Indicates we should only allow I/O to
 110                                  * one of the luns for the device at a
 111                                  * time. */
 112         unsigned was_reset:1;   /* There was a bus reset on the bus for
 113                                  * this device */
 114         unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
 115                                      * because we did a bus reset. */
 116         unsigned use_10_for_rw:1; /* first try 10-byte read / write */
 117         unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
 118         unsigned skip_ms_page_8:1;      /* do not use MODE SENSE page 0x08 */
 119         unsigned skip_ms_page_3f:1;     /* do not use MODE SENSE page 0x3f */
 120         unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
 121         unsigned no_start_on_add:1;     /* do not issue start on add */
 122         unsigned allow_restart:1; /* issue START_UNIT in error handler */
 123         unsigned manage_start_stop:1;   /* Let HLD (sd) manage start/stop */
 124         unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
 125         unsigned select_no_atn:1;
 126         unsigned fix_capacity:1;        /* READ_CAPACITY is too high by 1 */
 127         unsigned guess_capacity:1;      /* READ_CAPACITY might be too high by 1 */
 128         unsigned retry_hwerror:1;       /* Retry HARDWARE_ERROR */
 129
 130         unsigned int device_blocked;    /* Device returned QUEUE_FULL. */
 131
 132         unsigned int max_device_blocked; /* what device_blocked counts down from  */
 133 #define SCSI_DEFAULT_DEVICE_BLOCKED     3
 134
 135         atomic_t iorequest_cnt;
 136         atomic_t iodone_cnt;
 137         atomic_t ioerr_cnt;
 138
 139         int timeout;
 140
 141         struct device           sdev_gendev;
 142         struct class_device     sdev_classdev;
 143
 144         struct execute_work     ew; /* used to get process context on put */
 145
 146         enum scsi_device_state sdev_state;
 147         unsigned long           sdev_data[0];
 148 } __attribute__((aligned(sizeof(unsigned long))));
 149 #define to_scsi_device(d)       \
 150         container_of(d, struct scsi_device, sdev_gendev)
 151 #define class_to_sdev(d)        \
 152         container_of(d, struct scsi_device, sdev_classdev)
 153 #define transport_class_to_sdev(class_dev) \
 154         to_scsi_device(class_dev->dev)
 155
 156 #define sdev_printk(prefix, sdev, fmt, a...)    \
 157         dev_printk(prefix, &(sdev)->sdev_gendev, fmt, ##a)
 158
 159 #define scmd_printk(prefix, scmd, fmt, a...)                            \
 160         (scmd)->request->rq_disk ?                                      \
 161         sdev_printk(prefix, (scmd)->device, "[%s] " fmt,                \
 162                     (scmd)->request->rq_disk->disk_name, ##a) :         \
 163         sdev_printk(prefix, (scmd)->device, fmt, ##a)
 164
 165 enum scsi_target_state {
 166         STARGET_RUNNING = 1,
 167         STARGET_DEL,
 168 };
 169
 170 /*
 171  * scsi_target: representation of a scsi target, for now, this is only
 172  * used for single_lun devices. If no one has active IO to the target,
 173  * starget_sdev_user is NULL, else it points to the active sdev.
 174  */
 175 struct scsi_target {
 176         struct scsi_device      *starget_sdev_user;
 177         struct list_head        siblings;
 178         struct list_head        devices;
 179         struct device           dev;
 180         unsigned int            reap_ref; /* protected by the host lock */
 181         unsigned int            channel;
 182         unsigned int            id; /* target id ... replace
 183                                      * scsi_device.id eventually */
 184         unsigned int            create:1; /* signal that it needs to be added */
 185         unsigned int            pdt_1f_for_no_lun;      /* PDT = 0x1f */
 186                                                 /* means no lun present */
 187
 188         char                    scsi_level;
 189         struct execute_work     ew;
 190         enum scsi_target_state  state;
 191         void                    *hostdata; /* available to low-level driver */
 192         unsigned long           starget_data[0]; /* for the transport */
 193         /* starget_data must be the last element!!!! */
 194 } __attribute__((aligned(sizeof(unsigned long))));
 195
 196 #define to_scsi_target(d)       container_of(d, struct scsi_target, dev)
 197 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
 198 {
 199         return to_scsi_target(sdev->sdev_gendev.parent);
 200 }
 201 #define transport_class_to_starget(class_dev) \
 202         to_scsi_target(class_dev->dev)
 203
 204 #define starget_printk(prefix, starget, fmt, a...)      \
 205         dev_printk(prefix, &(starget)->dev, fmt, ##a)
 206
 207 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
 208                 uint, uint, uint, void *hostdata);
 209 extern int scsi_add_device(struct Scsi_Host *host, uint channel,
 210                            uint target, uint lun);
 211 extern void scsi_remove_device(struct scsi_device *);
 212
 213 extern int scsi_device_get(struct scsi_device *);
 214 extern void scsi_device_put(struct scsi_device *);
 215 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
 216                                               uint, uint, uint);
 217 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
 218                                                 uint, uint, uint);
 219 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
 220                                                         uint);
 221 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
 222                                                           uint);
 223 extern void starget_for_each_device(struct scsi_target *, void *,
 224                      void (*fn)(struct scsi_device *, void *));
 225
 226 /* only exposed to implement shost_for_each_device */
 227 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
 228                                                   struct scsi_device *);
 229
 230 /**
 231  * shost_for_each_device - iterate over all devices of a host
 232  * @sdev: the &struct scsi_device to use as a cursor
 233  * @shost: the &struct scsi_host to iterate over
 234  *
 235  * Iterator that returns each device attached to @shost.  This loop
 236  * takes a reference on each device and releases it at the end.  If
 237  * you break out of the loop, you must call scsi_device_put(sdev).
 238  */
 239 #define shost_for_each_device(sdev, shost) \
 240         for ((sdev) = __scsi_iterate_devices((shost), NULL); \
 241              (sdev); \
 242              (sdev) = __scsi_iterate_devices((shost), (sdev)))
 243
 244 /**
 245  * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
 246  * @sdev: the &struct scsi_device to use as a cursor
 247  * @shost: the &struct scsi_host to iterate over
 248  *
 249  * Iterator that returns each device attached to @shost.  It does _not_
 250  * take a reference on the scsi_device, so the whole loop must be
 251  * protected by shost->host_lock.
 252  *
 253  * Note: The only reason to use this is because you need to access the
 254  * device list in interrupt context.  Otherwise you really want to use
 255  * shost_for_each_device instead.
 256  */
 257 #define __shost_for_each_device(sdev, shost) \
 258         list_for_each_entry((sdev), &((shost)->__devices), siblings)
 259
 260 extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
 261 extern int scsi_track_queue_full(struct scsi_device *, int);
 262
 263 extern int scsi_set_medium_removal(struct scsi_device *, char);
 264
 265 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 266                            unsigned char *buffer, int len, int timeout,
 267                            int retries, struct scsi_mode_data *data,
 268                            struct scsi_sense_hdr *);
 269 extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
 270                             int modepage, unsigned char *buffer, int len,
 271                             int timeout, int retries,
 272                             struct scsi_mode_data *data,
 273                             struct scsi_sense_hdr *);
 274 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
 275                                 int retries);
 276 extern int scsi_device_set_state(struct scsi_device *sdev,
 277                                  enum scsi_device_state state);
 278 extern int scsi_device_quiesce(struct scsi_device *sdev);
 279 extern void scsi_device_resume(struct scsi_device *sdev);
 280 extern void scsi_target_quiesce(struct scsi_target *);
 281 extern void scsi_target_resume(struct scsi_target *);
 282 extern void scsi_scan_target(struct device *parent, unsigned int channel,
 283                              unsigned int id, unsigned int lun, int rescan);
 284 extern void scsi_target_reap(struct scsi_target *);
 285 extern void scsi_target_block(struct device *);
 286 extern void scsi_target_unblock(struct device *);
 287 extern void scsi_remove_target(struct device *);
 288 extern void int_to_scsilun(unsigned int, struct scsi_lun *);
 289 extern int scsilun_to_int(struct scsi_lun *);
 290 extern const char *scsi_device_state_name(enum scsi_device_state);
 291 extern int scsi_is_sdev_device(const struct device *);
 292 extern int scsi_is_target_device(const struct device *);
 293 extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 294                         int data_direction, void *buffer, unsigned bufflen,
 295                         unsigned char *sense, int timeout, int retries,
 296                         int flag);
 297 extern int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
 298                             int data_direction, void *buffer, unsigned bufflen,
 299                             struct scsi_sense_hdr *, int timeout, int retries);
 300 extern int scsi_execute_async(struct scsi_device *sdev,
 301                               const unsigned char *cmd, int cmd_len, int data_direction,
 302                               void *buffer, unsigned bufflen, int use_sg,
 303                               int timeout, int retries, void *privdata,
 304                               void (*done)(void *, char *, int, int),
 305                               gfp_t gfp);
 306
 307 static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
 308 {
 309         return device_reprobe(&sdev->sdev_gendev);
 310 }
 311
 312 static inline unsigned int sdev_channel(struct scsi_device *sdev)
 313 {
 314         return sdev->channel;
 315 }
 316
 317 static inline unsigned int sdev_id(struct scsi_device *sdev)
 318 {
 319         return sdev->id;
 320 }
 321
 322 #define scmd_id(scmd) sdev_id((scmd)->device)
 323 #define scmd_channel(scmd) sdev_channel((scmd)->device)
 324
 325 static inline int scsi_device_online(struct scsi_device *sdev)
 326 {
 327         return sdev->sdev_state != SDEV_OFFLINE;
 328 }
 329
 330 /* accessor functions for the SCSI parameters */
 331 static inline int scsi_device_sync(struct scsi_device *sdev)
 332 {
 333         return sdev->sdtr;
 334 }
 335 static inline int scsi_device_wide(struct scsi_device *sdev)
 336 {
 337         return sdev->wdtr;
 338 }
 339 static inline int scsi_device_dt(struct scsi_device *sdev)
 340 {
 341         return sdev->ppr;
 342 }
 343 static inline int scsi_device_dt_only(struct scsi_device *sdev)
 344 {
 345         if (sdev->inquiry_len < 57)
 346                 return 0;
 347         return (sdev->inquiry[56] & 0x0c) == 0x04;
 348 }
 349 static inline int scsi_device_ius(struct scsi_device *sdev)
 350 {
 351         if (sdev->inquiry_len < 57)
 352                 return 0;
 353         return sdev->inquiry[56] & 0x01;
 354 }
 355 static inline int scsi_device_qas(struct scsi_device *sdev)
 356 {
 357         if (sdev->inquiry_len < 57)
 358                 return 0;
 359         return sdev->inquiry[56] & 0x02;
 360 }
 361
 362 #define MODULE_ALIAS_SCSI_DEVICE(type) \
 363         MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 364 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"
 365
 366 #endif /* _SCSI_SCSI_DEVICE_H */