kernel-ark/include/scsi/scsi_device.h
Matthew Wilcox 3e082a910d [SCSI] Add ability to scan scsi busses asynchronously
Since it often takes around 20-30 seconds to scan a scsi bus, it's
highly advantageous to do this in parallel with other things.  The bulk
of this patch is ensuring that devices don't change numbering, and that
all devices are discovered prior to trying to start init.  For those
who build SCSI as modules, there's a new scsi_wait_scan module that will
ensure all bus scans are finished.

This patch only handles drivers which call scsi_scan_host.  Fibre Channel,
SAS, SATA, USB and Firewire all need additional work.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-10-11 13:44:25 -05:00

356 lines
13 KiB
C

#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 <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. */
};
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 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;/* don't let QUEUE_FULLs on the same
jiffie count on our counter, they
could all be from the same event. */
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 single_lun:1; /* Indicates we should only allow I/O to
* one of the luns for the device at a
* time. */
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 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 retry_hwerror:1; /* Retry HARDWARE_ERROR */
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;
int timeout;
struct device sdev_gendev;
struct class_device sdev_classdev;
struct execute_work ew; /* used to get process context on put */
enum scsi_device_state sdev_state;
unsigned long sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));
#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_classdev)
#define transport_class_to_sdev(class_dev) \
to_scsi_device(class_dev->dev)
#define sdev_printk(prefix, sdev, fmt, a...) \
dev_printk(prefix, &(sdev)->sdev_gendev, fmt, ##a)
#define scmd_printk(prefix, scmd, fmt, a...) \
dev_printk(prefix, &(scmd)->device->sdev_gendev, fmt, ##a)
enum scsi_target_state {
STARGET_RUNNING = 1,
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 pdt_1f_for_no_lun; /* PDT = 0x1f */
/* means no lun present */
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_gendev.parent);
}
#define transport_class_to_starget(class_dev) \
to_scsi_target(class_dev->dev)
#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, uint, void *hostdata);
extern int scsi_add_device(struct Scsi_Host *host, uint channel,
uint target, uint lun);
extern void scsi_remove_device(struct scsi_device *);
extern int scsi_device_cancel(struct scsi_device *, int);
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, uint);
extern struct scsi_device *__scsi_device_lookup(struct Scsi_Host *,
uint, uint, uint);
extern struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *,
uint);
extern struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *,
uint);
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);
extern int scsi_device_set_state(struct scsi_device *sdev,
enum scsi_device_state state);
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, unsigned int 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 *);
extern void scsi_remove_target(struct device *);
extern void int_to_scsilun(unsigned 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,
int flag);
extern int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd,
int data_direction, void *buffer, unsigned bufflen,
struct scsi_sense_hdr *, int timeout, int retries);
extern int scsi_execute_async(struct scsi_device *sdev,
const unsigned char *cmd, int cmd_len, int data_direction,
void *buffer, unsigned bufflen, int use_sg,
int timeout, int retries, void *privdata,
void (*done)(void *, char *, int, int),
gfp_t gfp);
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)
static inline int scsi_device_online(struct scsi_device *sdev)
{
return sdev->sdev_state != SDEV_OFFLINE;
}
/* 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;
}
#endif /* _SCSI_SCSI_DEVICE_H */