[SCSI] sr,sd: send media state change modification events

This will send for a card reader slot (remove/add media):
  UEVENT[1187091572.155884] change   /devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/host7/target7:0:0/7:0:0:0 (scsi)
  UEVENT[1187091572.162314] remove   /block/sdb/sdb1 (block)
  UEVENT[1187091572.172464] add      /block/sdb/sdb1 (block)
  UEVENT[1187091572.175408] change   /devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/host7/target7:0:0/7:0:0:0 (scsi)

and for a DVD drive (add/eject media):
  UEVENT[1187091590.189159] change   /devices/pci0000:00/0000:00:1f.1/host4/target4:0:0/4:0:0:0 (scsi)
  UEVENT[1187091590.957124] add      /module/isofs (module)
  UEVENT[1187091604.468207] change   /devices/pci0000:00/0000:00:1f.1/host4/target4:0:0/4:0:0:0 (scsi)

Userspace gets events, even for unpartitioned media. This unifies
the event handling for asynchronoous events (AN) and events caused by
perodical polling the device from userspace.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>

[jejb: modified for new event API]

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/scsi/sr.h b/drivers/scsi/sr.h
index d65de9621b27..0d04e2878c9d 100644
--- a/drivers/scsi/sr.h
+++ b/drivers/scsi/sr.h
@@ -37,6 +37,7 @@ typedef struct scsi_cd {
         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 */