alistair23-linux/drivers/scsi/sr.h
Tejun Heo 9f8a2c23c6 scsi: replace sr_test_unit_ready() with scsi_test_unit_ready()
The usage of TUR has been confusing involving several different
commits updating different parts over time.  Currently, the only
differences between scsi_test_unit_ready() and sr_test_unit_ready()
are,

* scsi_test_unit_ready() also sets sdev->changed on NOT_READY.

* scsi_test_unit_ready() returns 0 if TUR ended with UNIT_ATTENTION or
  NOT_READY.

Due to the above two differences, sr is using its own
sr_test_unit_ready(), but sd - the sole user of the above extra
handling - doesn't even need them.

Where scsi_test_unit_ready() is used in sd_media_changed(), the code
is looking for device ready w/ media present state which is true iff
TUR succeeds w/o sense data or UA, and when the device is not ready
for whatever reason sd_media_changed() explicitly marks media as
missing so there's no reason to set sdev->changed automatically from
scsi_test_unit_ready() on NOT_READY.

Drop both special handlings from scsi_test_unit_ready(), which makes
it equivalant to sr_test_unit_ready(), and replace
sr_test_unit_ready() with scsi_test_unit_ready().  Also, drop the
unnecessary explicit NOT_READY check from sd_media_changed().
Checking return value is enough for testing device readiness.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-16 17:53:39 +01:00

71 lines
2.2 KiB
C

/*
* sr.h by David Giller
* CD-ROM disk driver header file
*
* adapted from:
* sd.h Copyright (C) 1992 Drew Eckhardt
* SCSI disk driver header file by
* Drew Eckhardt
*
* <drew@colorado.edu>
*
* Modified by Eric Youngdale eric@andante.org to
* add scatter-gather, multiple outstanding request, and other
* enhancements.
*/
#ifndef _SR_H
#define _SR_H
#include <linux/genhd.h>
#include <linux/kref.h>
#define MAX_RETRIES 3
#define SR_TIMEOUT (30 * HZ)
struct scsi_device;
/* The CDROM is fairly slow, so we need a little extra time */
/* In fact, it is very slow if it has to spin up first */
#define IOCTL_TIMEOUT 30*HZ
typedef struct scsi_cd {
struct scsi_driver *driver;
unsigned capacity; /* size in blocks */
struct scsi_device *device;
unsigned int vendor; /* vendor code, see sr_vendor.c */
unsigned long ms_offset; /* for reading multisession-CD's */
unsigned use:1; /* is this device still supportable */
unsigned xa_flag:1; /* CD has XA sectors ? */
unsigned readcd_known:1; /* drive supports READ_CD (0xbe) */
unsigned readcd_cdda:1; /* reading audio data using READ_CD */
unsigned previous_state:1; /* media has changed */
struct cdrom_device_info cdi;
/* We hold gendisk and scsi_device references on probe and use
* the refs on this kref to decide when to release them */
struct kref kref;
struct gendisk *disk;
} Scsi_CD;
int sr_do_ioctl(Scsi_CD *, struct packet_command *);
int sr_lock_door(struct cdrom_device_info *, int);
int sr_tray_move(struct cdrom_device_info *, int);
int sr_drive_status(struct cdrom_device_info *, int);
int sr_disk_status(struct cdrom_device_info *);
int sr_get_last_session(struct cdrom_device_info *, struct cdrom_multisession *);
int sr_get_mcn(struct cdrom_device_info *, struct cdrom_mcn *);
int sr_reset(struct cdrom_device_info *);
int sr_select_speed(struct cdrom_device_info *cdi, int speed);
int sr_audio_ioctl(struct cdrom_device_info *, unsigned int, void *);
int sr_is_xa(Scsi_CD *);
/* sr_vendor.c */
void sr_vendor_init(Scsi_CD *);
int sr_cd_check(struct cdrom_device_info *);
int sr_set_blocklength(Scsi_CD *, int blocklength);
#endif