if i understand correctly, the BLKRRPART just does a rescan_partitions()
and does not do any INQUIRY and READ_CAPACITY to get the
capacity and geometry information again, as normally, this would
already be done.
This ioctl is meant for a failover type configuration where two hosts
have access to the storage. Host A does a scsi reservation of the storage,
preventing the Host B from being able to talk to it. So Host B can't do
the READ_CAPACITY successfully. (this is on purpose).
This ioctl is used upon failover. When Host B detects that Host A is failed,
Host B would make sure host A is_really_ dead, for example
by depriving it of power, and break the scsi reservation. Then it uses
this ioctl to get the geometry and capacity information and rescan
the partitions.
Maybe it should use 2 ioctls? One special one to get the geometry
and capacity info, and then the BLKRRPART ioctl to rescan partitions?
Hope that makes sense.
-- steve
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/