ide: Convert to bdops->check_events()

Convert ->media_changed() to the new ->check_events() method. The
conversion is mostly mechanical. The only notable change is that
cdrom now doesn't generate any event if @slot_nr isn't CDSL_CURRENT.
It used to return -EINVAL which would be treated as media changed. As
media changer isn't supported anyway, this doesn't make any
difference.

This makes ide emit the standard disk events and allows kernel event
polling. Currently, only MEDIA_CHANGE event is implemented. Adding
support for EJECT_REQUEST shouldn't be difficult; however, given that
ide driver is already deprecated, it probably is best to leave it
alone.

Signed-off-by: Tejun Heo <[e-mail]>
Acked-by: Jens Axboe <[e-mail]>
Cc: Kay Sievers <[e-mail]>
Cc: "David S. Miller" <[e-mail]>
Cc: [e-mail]

drivers/ide/ide-cd.c

···
 	.open			= ide_cdrom_open_real,
 	.release		= ide_cdrom_release_real,
 	.drive_status		= ide_cdrom_drive_status,
-	.media_changed		= ide_cdrom_check_media_change_real,
+	.check_events		= ide_cdrom_check_events_real,
 	.tray_move		= ide_cdrom_tray_move,
 	.lock_door		= ide_cdrom_lock_door,
 	.select_speed		= ide_cdrom_select_speed,
···
 }
 
 
-static int idecd_media_changed(struct gendisk *disk)
+static unsigned int idecd_check_events(struct gendisk *disk,
+				       unsigned int clearing)
 {
 	struct cdrom_info *info = ide_drv_g(disk, cdrom_info);
-	return cdrom_media_changed(&info->devinfo);
+	return cdrom_check_events(&info->devinfo, clearing);
 }
 
 static int idecd_revalidate_disk(struct gendisk *disk)
···
 	.open			= idecd_open,
 	.release		= idecd_release,
 	.ioctl			= idecd_ioctl,
-	.media_changed		= idecd_media_changed,
+	.check_events		= idecd_check_events,
 	.revalidate_disk	= idecd_revalidate_disk
 };
 
···
 	ide_cd_read_toc(drive, &sense);
 	g->fops = &idecd_ops;
 	g->flags |= GENHD_FL_REMOVABLE;
+	g->events = DISK_EVENT_MEDIA_CHANGE;
 	add_disk(g);
 	return 0;
 

drivers/ide/ide-cd.h

···
 int ide_cdrom_open_real(struct cdrom_device_info *, int);
 void ide_cdrom_release_real(struct cdrom_device_info *);
 int ide_cdrom_drive_status(struct cdrom_device_info *, int);
-int ide_cdrom_check_media_change_real(struct cdrom_device_info *, int);
+unsigned int ide_cdrom_check_events_real(struct cdrom_device_info *,
+					 unsigned int clearing, int slot_nr);
 int ide_cdrom_tray_move(struct cdrom_device_info *, int);
 int ide_cdrom_lock_door(struct cdrom_device_info *, int);
 int ide_cdrom_select_speed(struct cdrom_device_info *, int);

drivers/ide/ide-cd_ioctl.c

···
 	return CDS_DRIVE_NOT_READY;
 }
 
-int ide_cdrom_check_media_change_real(struct cdrom_device_info *cdi,
-				       int slot_nr)
+unsigned int ide_cdrom_check_events_real(struct cdrom_device_info *cdi,
+					 unsigned int clearing, int slot_nr)
 {
 	ide_drive_t *drive = cdi->handle;
 	int retval;
···
 		(void) cdrom_check_status(drive, NULL);
 		retval = (drive->dev_flags & IDE_DFLAG_MEDIA_CHANGED) ? 1 : 0;
 		drive->dev_flags &= ~IDE_DFLAG_MEDIA_CHANGED;
-		return retval;
+		return retval ? DISK_EVENT_MEDIA_CHANGE : 0;
 	} else {
-		return -EINVAL;
+		return 0;
 	}
 }
 

drivers/ide/ide-gd.c

···
 	return 0;
 }
 
-static int ide_gd_media_changed(struct gendisk *disk)
+static unsigned int ide_gd_check_events(struct gendisk *disk,
+					unsigned int clearing)
 {
 	struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
 	ide_drive_t *drive = idkp->drive;
-	int ret;
+	bool ret;
 
 	/* do not scan partitions twice if this is a removable device */
 	if (drive->dev_flags & IDE_DFLAG_ATTACH) {
···
 		return 0;
 	}
 
-	ret = !!(drive->dev_flags & IDE_DFLAG_MEDIA_CHANGED);
+	ret = drive->dev_flags & IDE_DFLAG_MEDIA_CHANGED;
 	drive->dev_flags &= ~IDE_DFLAG_MEDIA_CHANGED;
 
-	return ret;
+	return ret ? DISK_EVENT_MEDIA_CHANGE : 0;
 }
 
 static void ide_gd_unlock_native_capacity(struct gendisk *disk)
···
 	struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
 	ide_drive_t *drive = idkp->drive;
 
-	if (ide_gd_media_changed(disk))
+	if (ide_gd_check_events(disk, 0))
 		drive->disk_ops->get_capacity(drive);
 
 	set_capacity(disk, ide_gd_capacity(drive));
···
 	.release		= ide_gd_release,
 	.ioctl			= ide_gd_ioctl,
 	.getgeo			= ide_gd_getgeo,
-	.media_changed		= ide_gd_media_changed,
+	.check_events		= ide_gd_check_events,
 	.unlock_native_capacity	= ide_gd_unlock_native_capacity,
 	.revalidate_disk	= ide_gd_revalidate_disk
 };
···
 	if (drive->dev_flags & IDE_DFLAG_REMOVABLE)
 		g->flags = GENHD_FL_REMOVABLE;
 	g->fops = &ide_gd_ops;
+	g->events = DISK_EVENT_MEDIA_CHANGE;
 	add_disk(g);
 	return 0;