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#ifndef _SCSI_SCSI_DEVICE_H
#define _SCSI_SCSI_DEVICE_H
#include <linux/device.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/blkdev.h>
#include <scsi/scsi.h>
#include <asm/atomic.h>
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_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_LAST = SDEV_EVT_MEDIA_CHANGE,
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 */
/* this is now protected by the request_queue->queue_lock */
unsigned int device_busy; /* commands actually active on
* low-level. protected by queue_lock. */
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, lun, channel;
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 */
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 writeable:1;
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 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 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 */
DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */
struct list_head event_list; /* asserted events */
struct work_struct event_work;
unsigned int device_blocked; /* Device returned QUEUE_FULL. */
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 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 *);
};
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 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)
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;
unsigned int reap_ref; /* protected by the host lock */
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; /* PDT = 0x1f */
/* means no lun present */
/* commands actually active on LLD. protected by host lock. */
unsigned int target_busy;
/*
* 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 target_blocked;
unsigned int max_target_blocked;
#define SCSI_DEFAULT_TARGET_BLOCKED 3
char scsi_level;
struct execute_work ew;
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
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