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 <asm/atomic.h>
   8
   9 struct request_queue;
  10 struct scsi_cmnd;
  11 struct scsi_mode_data;
  12
  13
  14 /*
  15  * sdev state: If you alter this, you also need to alter scsi_sysfs.c
  16  * (for the ascii descriptions) and the state model enforcer:
  17  * scsi_lib:scsi_device_set_state().
  18  */
  19 enum scsi_device_state {
  20         SDEV_CREATED = 1,       /* device created but not added to sysfs
  21                                  * Only internal commands allowed (for inq) */
  22         SDEV_RUNNING,           /* device properly configured
  23                                  * All commands allowed */
  24         SDEV_CANCEL,            /* beginning to delete device
  25                                  * Only error handler commands allowed */
  26         SDEV_DEL,               /* device deleted
  27                                  * no commands allowed */
  28         SDEV_QUIESCE,           /* Device quiescent.  No block commands
  29                                  * will be accepted, only specials (which
  30                                  * originate in the mid-layer) */
  31         SDEV_OFFLINE,           /* Device offlined (by error handling or
  32                                  * user request */
  33         SDEV_BLOCK,             /* Device blocked by scsi lld.  No scsi
  34                                  * commands from user or midlayer should be issued
  35                                  * to the scsi lld. */
  36 };
  37
  38 struct scsi_device {
  39         struct Scsi_Host *host;
  40         struct request_queue *request_queue;
  41
  42         /* the next two are protected by the host->host_lock */
  43         struct list_head    siblings;   /* list of all devices on this host */
  44         struct list_head    same_target_siblings; /* just the devices sharing same target id */
  45
  46         /* this is now protected by the request_queue->queue_lock */
  47         unsigned int device_busy;       /* commands actually active on
  48                                          * low-level. protected by queue_lock. */
  49         spinlock_t list_lock;
  50         struct list_head cmd_list;      /* queue of in use SCSI Command structures */
  51         struct list_head starved_entry;
  52         struct scsi_cmnd *current_cmnd; /* currently active command */
  53         unsigned short queue_depth;     /* How deep of a queue we want */
  54         unsigned short last_queue_full_depth; /* These two are used by */
  55         unsigned short last_queue_full_count; /* scsi_track_queue_full() */
  56         unsigned long last_queue_full_time;/* don't let QUEUE_FULLs on the same
  57                                            jiffie count on our counter, they
  58                                            could all be from the same event. */
  59
  60         unsigned int id, lun, channel;
  61
  62         unsigned int manufacturer;      /* Manufacturer of device, for using
  63                                          * vendor-specific cmd's */
  64         unsigned sector_size;   /* size in bytes */
  65
  66         void *hostdata;         /* available to low-level driver */
  67         char devfs_name[256];   /* devfs junk */
  68         char type;
  69         char scsi_level;
  70         char inq_periph_qual;   /* PQ from INQUIRY data */
  71         unsigned char inquiry_len;      /* valid bytes in 'inquiry' */
  72         unsigned char * inquiry;        /* INQUIRY response data */
  73         char * vendor;          /* [back_compat] point into 'inquiry' ... */
  74         char * model;           /* ... after scan; point to static string */
  75         char * rev;             /* ... "nullnullnullnull" before scan */
  76         unsigned char current_tag;      /* current tag */
  77         struct scsi_target      *sdev_target;   /* used only for single_lun */
  78
  79         unsigned int    sdev_bflags; /* black/white flags as also found in
  80                                  * scsi_devinfo.[hc]. For now used only to
  81                                  * pass settings from slave_alloc to scsi
  82                                  * core. */
  83         unsigned writeable:1;
  84         unsigned removable:1;
  85         unsigned changed:1;     /* Data invalid due to media change */
  86         unsigned busy:1;        /* Used to prevent races */
  87         unsigned lockable:1;    /* Able to prevent media removal */
  88         unsigned locked:1;      /* Media removal disabled */
  89         unsigned borken:1;      /* Tell the Seagate driver to be
  90                                  * painfully slow on this device */
  91         unsigned disconnect:1;  /* can disconnect */
  92         unsigned soft_reset:1;  /* Uses soft reset option */
  93         unsigned sdtr:1;        /* Device supports SDTR messages */
  94         unsigned wdtr:1;        /* Device supports WDTR messages */
  95         unsigned ppr:1;         /* Device supports PPR messages */
  96         unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
  97         unsigned simple_tags:1; /* simple queue tag messages are enabled */
  98         unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
  99         unsigned single_lun:1;  /* Indicates we should only allow I/O to
 100                                  * one of the luns for the device at a
 101                                  * time. */
 102         unsigned was_reset:1;   /* There was a bus reset on the bus for
 103                                  * this device */
 104         unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
 105                                      * because we did a bus reset. */
 106         unsigned use_10_for_rw:1; /* first try 10-byte read / write */
 107         unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
 108         unsigned skip_ms_page_8:1;      /* do not use MODE SENSE page 0x08 */
 109         unsigned skip_ms_page_3f:1;     /* do not use MODE SENSE page 0x3f */
 110         unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
 111         unsigned no_start_on_add:1;     /* do not issue start on add */
 112         unsigned allow_restart:1; /* issue START_UNIT in error handler */
 113         unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
 114         unsigned select_no_atn:1;
 115         unsigned fix_capacity:1;        /* READ_CAPACITY is too high by 1 */
 116         unsigned retry_hwerror:1;       /* Retry HARDWARE_ERROR */
 117
 118         unsigned int device_blocked;    /* Device returned QUEUE_FULL. */
 119
 120         unsigned int max_device_blocked; /* what device_blocked counts down from  */
 121 #define SCSI_DEFAULT_DEVICE_BLOCKED     3
 122
 123         atomic_t iorequest_cnt;
 124         atomic_t iodone_cnt;
 125         atomic_t ioerr_cnt;
 126
 127         int timeout;
 128
 129         struct device           sdev_gendev;
 130         struct class_device     sdev_classdev;
 131
 132         enum scsi_device_state sdev_state;
 133         unsigned long           sdev_data[0];
 134 } __attribute__((aligned(sizeof(unsigned long))));
 135 #define to_scsi_device(d)       \
 136         container_of(d, struct scsi_device, sdev_gendev)
 137 #define class_to_sdev(d)        \
 138         container_of(d, struct scsi_device, sdev_classdev)
 139 #define transport_class_to_sdev(class_dev) \
 140         to_scsi_device(class_dev->dev)
 141
 142 /*
 143  * scsi_target: representation of a scsi target, for now, this is only
 144  * used for single_lun devices. If no one has active IO to the target,
 145  * starget_sdev_user is NULL, else it points to the active sdev.
 146  */
 147 struct scsi_target {
 148         struct scsi_device      *starget_sdev_user;
 149         struct list_head        siblings;
 150         struct list_head        devices;
 151         struct device           dev;
 152         unsigned int            reap_ref; /* protected by the host lock */
 153         unsigned int            channel;
 154         unsigned int            id; /* target id ... replace
 155                                      * scsi_device.id eventually */
 156         unsigned long           create:1; /* signal that it needs to be added */
 157         unsigned long           starget_data[0];
 158 } __attribute__((aligned(sizeof(unsigned long))));
 159
 160 #define to_scsi_target(d)       container_of(d, struct scsi_target, dev)
 161 static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
 162 {
 163         return to_scsi_target(sdev->sdev_gendev.parent);
 164 }
 165 #define transport_class_to_starget(class_dev) \
 166         to_scsi_target(class_dev->dev)
 167
 168 extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
 169                 uint, uint, uint, void *hostdata);
 170 #define scsi_add_device(host, channel, target, lun) \
 171         __scsi_add_device(host, channel, target, lun, NULL)
 172 extern void scsi_remove_device(struct scsi_device *);
 173 extern int scsi_device_cancel(struct scsi_device *, int);
 174
 175 extern int scsi_device_get(struct scsi_device *);
 176 extern void scsi_device_put(struct scsi_device *);
 177 extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
 178                                               uint, uint, uint);
 179 extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
 180                                                 uint, uint, uint);
 181 extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
 182                                                         uint);
 183 extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
 184                                                           uint);
 185 extern void starget_for_each_device(struct scsi_target *, void *,
 186                      void (*fn)(struct scsi_device *, void *));
 187
 188 /* only exposed to implement shost_for_each_device */
 189 extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
 190                                                   struct scsi_device *);
 191
 192 /**
 193  * shost_for_each_device  -  iterate over all devices of a host
 194  * @sdev:       iterator
 195  * @host:       host whiches devices we want to iterate over
 196  *
 197  * This traverses over each devices of @shost.  The devices have
 198  * a reference that must be released by scsi_host_put when breaking
 199  * out of the loop.
 200  */
 201 #define shost_for_each_device(sdev, shost) \
 202         for ((sdev) = __scsi_iterate_devices((shost), NULL); \
 203              (sdev); \
 204              (sdev) = __scsi_iterate_devices((shost), (sdev)))
 205
 206 /**
 207  * __shost_for_each_device  -  iterate over all devices of a host (UNLOCKED)
 208  * @sdev:       iterator
 209  * @host:       host whiches devices we want to iterate over
 210  *
 211  * This traverses over each devices of @shost.  It does _not_ take a
 212  * reference on the scsi_device, thus it the whole loop must be protected
 213  * by shost->host_lock.
 214  *
 215  * Note:  The only reason why drivers would want to use this is because
 216  * they're need to access the device list in irq context.  Otherwise you
 217  * really want to use shost_for_each_device instead.
 218  */
 219 #define __shost_for_each_device(sdev, shost) \
 220         list_for_each_entry((sdev), &((shost)->__devices), siblings)
 221
 222 extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
 223 extern int scsi_track_queue_full(struct scsi_device *, int);
 224
 225 extern int scsi_set_medium_removal(struct scsi_device *, char);
 226
 227 extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
 228                            unsigned char *buffer, int len, int timeout,
 229                            int retries, struct scsi_mode_data *data);
 230 extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
 231                                 int retries);
 232 extern int scsi_device_set_state(struct scsi_device *sdev,
 233                                  enum scsi_device_state state);
 234 extern int scsi_device_quiesce(struct scsi_device *sdev);
 235 extern void scsi_device_resume(struct scsi_device *sdev);
 236 extern void scsi_target_quiesce(struct scsi_target *);
 237 extern void scsi_target_resume(struct scsi_target *);
 238 extern void scsi_scan_target(struct device *parent, unsigned int channel,
 239                              unsigned int id, unsigned int lun, int rescan);
 240 extern void scsi_target_reap(struct scsi_target *);
 241 extern void scsi_target_block(struct device *);
 242 extern void scsi_target_unblock(struct device *);
 243 extern void scsi_remove_target(struct device *);
 244 extern const char *scsi_device_state_name(enum scsi_device_state);
 245 extern int scsi_is_sdev_device(const struct device *);
 246 extern int scsi_is_target_device(const struct device *);
 247 static inline int scsi_device_online(struct scsi_device *sdev)
 248 {
 249         return sdev->sdev_state != SDEV_OFFLINE;
 250 }
 251
 252 /* accessor functions for the SCSI parameters */
 253 static inline int scsi_device_sync(struct scsi_device *sdev)
 254 {
 255         return sdev->sdtr;
 256 }
 257 static inline int scsi_device_wide(struct scsi_device *sdev)
 258 {
 259         return sdev->wdtr;
 260 }
 261 static inline int scsi_device_dt(struct scsi_device *sdev)
 262 {
 263         return sdev->ppr;
 264 }
 265 static inline int scsi_device_dt_only(struct scsi_device *sdev)
 266 {
 267         if (sdev->inquiry_len < 57)
 268                 return 0;
 269         return (sdev->inquiry[56] & 0x0c) == 0x04;
 270 }
 271 static inline int scsi_device_ius(struct scsi_device *sdev)
 272 {
 273         if (sdev->inquiry_len < 57)
 274                 return 0;
 275         return sdev->inquiry[56] & 0x01;
 276 }
 277 static inline int scsi_device_qas(struct scsi_device *sdev)
 278 {
 279         if (sdev->inquiry_len < 57)
 280                 return 0;
 281         return sdev->inquiry[56] & 0x02;
 282 }
 283 #endif /* _SCSI_SCSI_DEVICE_H */