root/include/scsi/scsi_device.h

INCLUDED FROM

DEFINITIONS

1. scsi_execute_req
2. scsi_autopm_get_device
3. scsi_autopm_put_device
4. scsi_device_reprobe
5. sdev_channel
6. sdev_id
7. scsi_device_online
8. scsi_device_blocked
9. scsi_device_created
10. scsi_device_sync
11. scsi_device_wide
12. scsi_device_dt
13. scsi_device_dt_only
14. scsi_device_ius
15. scsi_device_qas
16. scsi_device_enclosure
17. scsi_device_protection
18. scsi_device_tpgs

#ifndef _SCSI_SCSI_DEVICE_H
#define _SCSI_SCSI_DEVICE_H

#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/blkdev.h>
#include <scsi/scsi.h>
#include <linux/atomic.h>

struct device;
struct request_queue;
struct scsi_cmnd;
struct scsi_lun;
struct scsi_sense_hdr;

struct scsi_mode_data {
        __u32   length;
        __u16   block_descriptor_length;
        __u8    medium_type;
        __u8    device_specific;
        __u8    header_length;
        __u8    longlba:1;
};

/*
 * sdev state: If you alter this, you also need to alter scsi_sysfs.c
 * (for the ascii descriptions) and the state model enforcer:
 * scsi_lib:scsi_device_set_state().
 */
enum scsi_device_state {
        SDEV_CREATED = 1,       /* device created but not added to sysfs
                                 * Only internal commands allowed (for inq) */
        SDEV_RUNNING,           /* device properly configured
                                 * All commands allowed */
        SDEV_CANCEL,            /* beginning to delete device
                                 * Only error handler commands allowed */
        SDEV_DEL,               /* device deleted 
                                 * no commands allowed */
        SDEV_QUIESCE,           /* Device quiescent.  No block commands
                                 * will be accepted, only specials (which
                                 * originate in the mid-layer) */
        SDEV_OFFLINE,           /* Device offlined (by error handling or
                                 * user request */
        SDEV_TRANSPORT_OFFLINE, /* Offlined by transport class error handler */
        SDEV_BLOCK,             /* Device blocked by scsi lld.  No
                                 * scsi commands from user or midlayer
                                 * should be issued to the scsi
                                 * lld. */
        SDEV_CREATED_BLOCK,     /* same as above but for created devices */
};

enum scsi_device_event {
        SDEV_EVT_MEDIA_CHANGE   = 1,    /* media has changed */
        SDEV_EVT_INQUIRY_CHANGE_REPORTED,               /* 3F 03  UA reported */
        SDEV_EVT_CAPACITY_CHANGE_REPORTED,              /* 2A 09  UA reported */
        SDEV_EVT_SOFT_THRESHOLD_REACHED_REPORTED,       /* 38 07  UA reported */
        SDEV_EVT_MODE_PARAMETER_CHANGE_REPORTED,        /* 2A 01  UA reported */
        SDEV_EVT_LUN_CHANGE_REPORTED,                   /* 3F 0E  UA reported */

        SDEV_EVT_FIRST          = SDEV_EVT_MEDIA_CHANGE,
        SDEV_EVT_LAST           = SDEV_EVT_LUN_CHANGE_REPORTED,

        SDEV_EVT_MAXBITS        = SDEV_EVT_LAST + 1
};

struct scsi_event {
        enum scsi_device_event  evt_type;
        struct list_head        node;

        /* put union of data structures, for non-simple event types,
         * here
         */
};

struct scsi_device {
        struct Scsi_Host *host;
        struct request_queue *request_queue;

        /* the next two are protected by the host->host_lock */
        struct list_head    siblings;   /* list of all devices on this host */
        struct list_head    same_target_siblings; /* just the devices sharing same target id */

        atomic_t device_busy;           /* commands actually active on LLDD */
        atomic_t device_blocked;        /* Device returned QUEUE_FULL. */

        spinlock_t list_lock;
        struct list_head cmd_list;      /* queue of in use SCSI Command structures */
        struct list_head starved_entry;
        struct scsi_cmnd *current_cmnd; /* currently active command */
        unsigned short queue_depth;     /* How deep of a queue we want */
        unsigned short max_queue_depth; /* max queue depth */
        unsigned short last_queue_full_depth; /* These two are used by */
        unsigned short last_queue_full_count; /* scsi_track_queue_full() */
        unsigned long last_queue_full_time;     /* last queue full time */
        unsigned long queue_ramp_up_period;     /* ramp up period in jiffies */
#define SCSI_DEFAULT_RAMP_UP_PERIOD     (120 * HZ)

        unsigned long last_queue_ramp_up;       /* last queue ramp up time */

        unsigned int id, channel;
        u64 lun;
        unsigned int manufacturer;      /* Manufacturer of device, for using 
                                         * vendor-specific cmd's */
        unsigned sector_size;   /* size in bytes */

        void *hostdata;         /* available to low-level driver */
        char type;
        char scsi_level;
        char inq_periph_qual;   /* PQ from INQUIRY data */      
        unsigned char inquiry_len;      /* valid bytes in 'inquiry' */
        unsigned char * inquiry;        /* INQUIRY response data */
        const char * vendor;            /* [back_compat] point into 'inquiry' ... */
        const char * model;             /* ... after scan; point to static string */
        const char * rev;               /* ... "nullnullnullnull" before scan */

#define SCSI_VPD_PG_LEN                255
        int vpd_pg83_len;
        unsigned char *vpd_pg83;
        int vpd_pg80_len;
        unsigned char *vpd_pg80;
        unsigned char current_tag;      /* current tag */
        struct scsi_target      *sdev_target;   /* used only for single_lun */

        unsigned int    sdev_bflags; /* black/white flags as also found in
                                 * scsi_devinfo.[hc]. For now used only to
                                 * pass settings from slave_alloc to scsi
                                 * core. */
        unsigned int eh_timeout; /* Error handling timeout */
        unsigned removable:1;
        unsigned changed:1;     /* Data invalid due to media change */
        unsigned busy:1;        /* Used to prevent races */
        unsigned lockable:1;    /* Able to prevent media removal */
        unsigned locked:1;      /* Media removal disabled */
        unsigned borken:1;      /* Tell the Seagate driver to be 
                                 * painfully slow on this device */
        unsigned disconnect:1;  /* can disconnect */
        unsigned soft_reset:1;  /* Uses soft reset option */
        unsigned sdtr:1;        /* Device supports SDTR messages */
        unsigned wdtr:1;        /* Device supports WDTR messages */
        unsigned ppr:1;         /* Device supports PPR messages */
        unsigned tagged_supported:1;    /* Supports SCSI-II tagged queuing */
        unsigned simple_tags:1; /* simple queue tag messages are enabled */
        unsigned ordered_tags:1;/* ordered queue tag messages are enabled */
        unsigned was_reset:1;   /* There was a bus reset on the bus for 
                                 * this device */
        unsigned expecting_cc_ua:1; /* Expecting a CHECK_CONDITION/UNIT_ATTN
                                     * because we did a bus reset. */
        unsigned use_10_for_rw:1; /* first try 10-byte read / write */
        unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
        unsigned no_report_opcodes:1;   /* no REPORT SUPPORTED OPERATION CODES */
        unsigned no_write_same:1;       /* no WRITE SAME command */
        unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
        unsigned skip_ms_page_8:1;      /* do not use MODE SENSE page 0x08 */
        unsigned skip_ms_page_3f:1;     /* do not use MODE SENSE page 0x3f */
        unsigned skip_vpd_pages:1;      /* do not read VPD pages */
        unsigned try_vpd_pages:1;       /* attempt to read VPD pages */
        unsigned use_192_bytes_for_3f:1; /* ask for 192 bytes from page 0x3f */
        unsigned no_start_on_add:1;     /* do not issue start on add */
        unsigned allow_restart:1; /* issue START_UNIT in error handler */
        unsigned manage_start_stop:1;   /* Let HLD (sd) manage start/stop */
        unsigned start_stop_pwr_cond:1; /* Set power cond. in START_STOP_UNIT */
        unsigned no_uld_attach:1; /* disable connecting to upper level drivers */
        unsigned select_no_atn:1;
        unsigned fix_capacity:1;        /* READ_CAPACITY is too high by 1 */
        unsigned guess_capacity:1;      /* READ_CAPACITY might be too high by 1 */
        unsigned retry_hwerror:1;       /* Retry HARDWARE_ERROR */
        unsigned last_sector_bug:1;     /* do not use multisector accesses on
                                           SD_LAST_BUGGY_SECTORS */
        unsigned no_read_disc_info:1;   /* Avoid READ_DISC_INFO cmds */
        unsigned no_read_capacity_16:1; /* Avoid READ_CAPACITY_16 cmds */
        unsigned try_rc_10_first:1;     /* Try READ_CAPACACITY_10 first */
        unsigned is_visible:1;  /* is the device visible in sysfs */
        unsigned wce_default_on:1;      /* Cache is ON by default */
        unsigned no_dif:1;      /* T10 PI (DIF) should be disabled */
        unsigned broken_fua:1;          /* Don't set FUA bit */
        unsigned lun_in_cdb:1;          /* Store LUN bits in CDB[1] */

        atomic_t disk_events_disable_depth; /* disable depth for disk events */

        DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
        DECLARE_BITMAP(pending_events, SDEV_EVT_MAXBITS); /* pending events */
        struct list_head event_list;    /* asserted events */
        struct work_struct event_work;

        unsigned int max_device_blocked; /* what device_blocked counts down from  */
#define SCSI_DEFAULT_DEVICE_BLOCKED     3

        atomic_t iorequest_cnt;
        atomic_t iodone_cnt;
        atomic_t ioerr_cnt;

        struct device           sdev_gendev,
                                sdev_dev;

        struct execute_work     ew; /* used to get process context on put */
        struct work_struct      requeue_work;

        struct scsi_dh_data     *scsi_dh_data;
        enum scsi_device_state sdev_state;
        unsigned long           sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));

struct scsi_dh_devlist {
        char *vendor;
        char *model;
};

typedef void (*activate_complete)(void *, int);
struct scsi_device_handler {
        /* Used by the infrastructure */
        struct list_head list; /* list of scsi_device_handlers */

        /* Filled by the hardware handler */
        struct module *module;
        const char *name;
        const struct scsi_dh_devlist *devlist;
        int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *);
        int (*attach)(struct scsi_device *);
        void (*detach)(struct scsi_device *);
        int (*activate)(struct scsi_device *, activate_complete, void *);
        int (*prep_fn)(struct scsi_device *, struct request *);
        int (*set_params)(struct scsi_device *, const char *);
        bool (*match)(struct scsi_device *);
};

struct scsi_dh_data {
        struct scsi_device_handler *scsi_dh;
        struct scsi_device *sdev;
        struct kref kref;
        char buf[0];
};

#define to_scsi_device(d)       \
        container_of(d, struct scsi_device, sdev_gendev)
#define class_to_sdev(d)        \
        container_of(d, struct scsi_device, sdev_dev)
#define transport_class_to_sdev(class_dev) \
        to_scsi_device(class_dev->parent)

#define sdev_printk(prefix, sdev, fmt, a...)    \
        dev_printk(prefix, &(sdev)->sdev_gendev, fmt, ##a)

#define sdev_dbg(sdev, fmt, a...) \
        dev_dbg(&(sdev)->sdev_gendev, fmt, ##a)

#define scmd_printk(prefix, scmd, fmt, a...)                            \
        (scmd)->request->rq_disk ?                                      \
        sdev_printk(prefix, (scmd)->device, "[%s] " fmt,                \
                    (scmd)->request->rq_disk->disk_name, ##a) :         \
        sdev_printk(prefix, (scmd)->device, fmt, ##a)

#define scmd_dbg(scmd, fmt, a...)                                          \
        do {                                                               \
                if ((scmd)->request->rq_disk)                              \
                        sdev_dbg((scmd)->device, "[%s] " fmt,              \
                                 (scmd)->request->rq_disk->disk_name, ##a);\
                else                                                       \
                        sdev_dbg((scmd)->device, fmt, ##a);                \
        } while (0)

enum scsi_target_state {
        STARGET_CREATED = 1,
        STARGET_RUNNING,
        STARGET_DEL,
};

/*
 * scsi_target: representation of a scsi target, for now, this is only
 * used for single_lun devices. If no one has active IO to the target,
 * starget_sdev_user is NULL, else it points to the active sdev.
 */
struct scsi_target {
        struct scsi_device      *starget_sdev_user;
        struct list_head        siblings;
        struct list_head        devices;
        struct device           dev;
        struct kref             reap_ref; /* last put renders target invisible */
        unsigned int            channel;
        unsigned int            id; /* target id ... replace
                                     * scsi_device.id eventually */
        unsigned int            create:1; /* signal that it needs to be added */
        unsigned int            single_lun:1;   /* Indicates we should only
                                                 * allow I/O to one of the luns
                                                 * for the device at a time. */
        unsigned int            pdt_1f_for_no_lun:1;    /* PDT = 0x1f
                                                 * means no lun present. */
        unsigned int            no_report_luns:1;       /* Don't use
                                                 * REPORT LUNS for scanning. */
        unsigned int            expecting_lun_change:1; /* A device has reported
                                                 * a 3F/0E UA, other devices on
                                                 * the same target will also. */
        /* commands actually active on LLD. */
        atomic_t                target_busy;
        atomic_t                target_blocked;

        /*
         * LLDs should set this in the slave_alloc host template callout.
         * If set to zero then there is not limit.
         */
        unsigned int            can_queue;
        unsigned int            max_target_blocked;
#define SCSI_DEFAULT_TARGET_BLOCKED     3

        char                    scsi_level;
        enum scsi_target_state  state;
        void                    *hostdata; /* available to low-level driver */
        unsigned long           starget_data[0]; /* for the transport */
        /* starget_data must be the last element!!!! */
} __attribute__((aligned(sizeof(unsigned long))));

#define to_scsi_target(d)       container_of(d, struct scsi_target, dev)
static inline struct scsi_target *scsi_target(struct scsi_device *sdev)
{
        return to_scsi_target(sdev->sdev_gendev.parent);
}
#define transport_class_to_starget(class_dev) \
        to_scsi_target(class_dev->parent)

#define starget_printk(prefix, starget, fmt, a...)      \
        dev_printk(prefix, &(starget)->dev, fmt, ##a)

extern struct scsi_device *__scsi_add_device(struct Scsi_Host *,
                uint, uint, u64, void *hostdata);
extern int scsi_add_device(struct Scsi_Host *host, uint channel,
                           uint target, u64 lun);
extern int scsi_register_device_handler(struct scsi_device_handler *scsi_dh);
extern void scsi_remove_device(struct scsi_device *);
extern int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh);
void scsi_attach_vpd(struct scsi_device *sdev);

extern int scsi_device_get(struct scsi_device *);
extern void scsi_device_put(struct scsi_device *);
extern struct scsi_device *scsi_device_lookup(struct Scsi_Host *,
                                              uint, uint, u64);
extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
                                                uint, uint, u64);
extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
                                                        u64);
extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
                                                          u64);
extern void starget_for_each_device(struct scsi_target *, void *,
                     void (*fn)(struct scsi_device *, void *));
extern void __starget_for_each_device(struct scsi_target *, void *,
                                      void (*fn)(struct scsi_device *,
                                                 void *));

/* only exposed to implement shost_for_each_device */
extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *,
                                                  struct scsi_device *);

/**
 * shost_for_each_device - iterate over all devices of a host
 * @sdev: the &struct scsi_device to use as a cursor
 * @shost: the &struct scsi_host to iterate over
 *
 * Iterator that returns each device attached to @shost.  This loop
 * takes a reference on each device and releases it at the end.  If
 * you break out of the loop, you must call scsi_device_put(sdev).
 */
#define shost_for_each_device(sdev, shost) \
        for ((sdev) = __scsi_iterate_devices((shost), NULL); \
             (sdev); \
             (sdev) = __scsi_iterate_devices((shost), (sdev)))

/**
 * __shost_for_each_device - iterate over all devices of a host (UNLOCKED)
 * @sdev: the &struct scsi_device to use as a cursor
 * @shost: the &struct scsi_host to iterate over
 *
 * Iterator that returns each device attached to @shost.  It does _not_
 * take a reference on the scsi_device, so the whole loop must be
 * protected by shost->host_lock.
 *
 * Note: The only reason to use this is because you need to access the
 * device list in interrupt context.  Otherwise you really want to use
 * shost_for_each_device instead.
 */
#define __shost_for_each_device(sdev, shost) \
        list_for_each_entry((sdev), &((shost)->__devices), siblings)

extern void scsi_adjust_queue_depth(struct scsi_device *, int, int);
extern int scsi_track_queue_full(struct scsi_device *, int);

extern int scsi_set_medium_removal(struct scsi_device *, char);

extern int scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
                           unsigned char *buffer, int len, int timeout,
                           int retries, struct scsi_mode_data *data,
                           struct scsi_sense_hdr *);
extern int scsi_mode_select(struct scsi_device *sdev, int pf, int sp,
                            int modepage, unsigned char *buffer, int len,
                            int timeout, int retries,
                            struct scsi_mode_data *data,
                            struct scsi_sense_hdr *);
extern int scsi_test_unit_ready(struct scsi_device *sdev, int timeout,
                                int retries, struct scsi_sense_hdr *sshdr);
extern int scsi_get_vpd_page(struct scsi_device *, u8 page, unsigned char *buf,
                             int buf_len);
extern int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer,
                              unsigned int len, unsigned char opcode);
extern int scsi_device_set_state(struct scsi_device *sdev,
                                 enum scsi_device_state state);
extern struct scsi_event *sdev_evt_alloc(enum scsi_device_event evt_type,
                                          gfp_t gfpflags);
extern void sdev_evt_send(struct scsi_device *sdev, struct scsi_event *evt);
extern void sdev_evt_send_simple(struct scsi_device *sdev,
                          enum scsi_device_event evt_type, gfp_t gfpflags);
extern int scsi_device_quiesce(struct scsi_device *sdev);
extern void scsi_device_resume(struct scsi_device *sdev);
extern void scsi_target_quiesce(struct scsi_target *);
extern void scsi_target_resume(struct scsi_target *);
extern void scsi_scan_target(struct device *parent, unsigned int channel,
                             unsigned int id, u64 lun, int rescan);
extern void scsi_target_reap(struct scsi_target *);
extern void scsi_target_block(struct device *);
extern void scsi_target_unblock(struct device *, enum scsi_device_state);
extern void scsi_remove_target(struct device *);
extern void int_to_scsilun(u64, struct scsi_lun *);
extern u64 scsilun_to_int(struct scsi_lun *);
extern const char *scsi_device_state_name(enum scsi_device_state);
extern int scsi_is_sdev_device(const struct device *);
extern int scsi_is_target_device(const struct device *);
extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
                        int data_direction, void *buffer, unsigned bufflen,
                        unsigned char *sense, int timeout, int retries,
                        u64 flags, int *resid);
extern int scsi_execute_req_flags(struct scsi_device *sdev,
        const unsigned char *cmd, int data_direction, void *buffer,
        unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
        int retries, int *resid, u64 flags);
static inline int scsi_execute_req(struct scsi_device *sdev,
        const unsigned char *cmd, int data_direction, void *buffer,
        unsigned bufflen, struct scsi_sense_hdr *sshdr, int timeout,
        int retries, int *resid)
{
        return scsi_execute_req_flags(sdev, cmd, data_direction, buffer,
                bufflen, sshdr, timeout, retries, resid, 0);
}
extern void sdev_disable_disk_events(struct scsi_device *sdev);
extern void sdev_enable_disk_events(struct scsi_device *sdev);

#ifdef CONFIG_PM_RUNTIME
extern int scsi_autopm_get_device(struct scsi_device *);
extern void scsi_autopm_put_device(struct scsi_device *);
#else
static inline int scsi_autopm_get_device(struct scsi_device *d) { return 0; }
static inline void scsi_autopm_put_device(struct scsi_device *d) {}
#endif /* CONFIG_PM_RUNTIME */

static inline int __must_check scsi_device_reprobe(struct scsi_device *sdev)
{
        return device_reprobe(&sdev->sdev_gendev);
}

static inline unsigned int sdev_channel(struct scsi_device *sdev)
{
        return sdev->channel;
}

static inline unsigned int sdev_id(struct scsi_device *sdev)
{
        return sdev->id;
}

#define scmd_id(scmd) sdev_id((scmd)->device)
#define scmd_channel(scmd) sdev_channel((scmd)->device)

/*
 * checks for positions of the SCSI state machine
 */
static inline int scsi_device_online(struct scsi_device *sdev)
{
        return (sdev->sdev_state != SDEV_OFFLINE &&
                sdev->sdev_state != SDEV_TRANSPORT_OFFLINE &&
                sdev->sdev_state != SDEV_DEL);
}
static inline int scsi_device_blocked(struct scsi_device *sdev)
{
        return sdev->sdev_state == SDEV_BLOCK ||
                sdev->sdev_state == SDEV_CREATED_BLOCK;
}
static inline int scsi_device_created(struct scsi_device *sdev)
{
        return sdev->sdev_state == SDEV_CREATED ||
                sdev->sdev_state == SDEV_CREATED_BLOCK;
}

/* accessor functions for the SCSI parameters */
static inline int scsi_device_sync(struct scsi_device *sdev)
{
        return sdev->sdtr;
}
static inline int scsi_device_wide(struct scsi_device *sdev)
{
        return sdev->wdtr;
}
static inline int scsi_device_dt(struct scsi_device *sdev)
{
        return sdev->ppr;
}
static inline int scsi_device_dt_only(struct scsi_device *sdev)
{
        if (sdev->inquiry_len < 57)
                return 0;
        return (sdev->inquiry[56] & 0x0c) == 0x04;
}
static inline int scsi_device_ius(struct scsi_device *sdev)
{
        if (sdev->inquiry_len < 57)
                return 0;
        return sdev->inquiry[56] & 0x01;
}
static inline int scsi_device_qas(struct scsi_device *sdev)
{
        if (sdev->inquiry_len < 57)
                return 0;
        return sdev->inquiry[56] & 0x02;
}
static inline int scsi_device_enclosure(struct scsi_device *sdev)
{
        return sdev->inquiry ? (sdev->inquiry[6] & (1<<6)) : 1;
}

static inline int scsi_device_protection(struct scsi_device *sdev)
{
        if (sdev->no_dif)
                return 0;

        return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
}

static inline int scsi_device_tpgs(struct scsi_device *sdev)
{
        return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
}

#define MODULE_ALIAS_SCSI_DEVICE(type) \
        MODULE_ALIAS("scsi:t-" __stringify(type) "*")
#define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"

#endif /* _SCSI_SCSI_DEVICE_H */