When calling scsi_dh_activate() we should be returning
SCSI_DH_NOTCONN if the device handler couldn't be attached.
Reviewed-by: Bart van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
The I/O submission and completion paths call into the device handler
without any synchronization agains detachment. So disallow detaching
device handlers at runtime.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
And cleanup the various messy opencoded versions of this. Note that this
moves the sdev_state checks outside the queue_lock coverage, but as
we don't hold the lock over the activation they are only advisory anyway.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Add a ->handler and a ->handler_data field to struct scsi_device and kill
this indirection. Also move struct scsi_device_handler to scsi_dh.h so that
changes to it don't require rebuilding every SCSI LLDD.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Add a single list of devices that need non-ALUA device handlers to the core
scsi_dh code so that we can autoload the modules for them at probe time.
While this is a little ugly in terms of architecture it actually
significantly simplifies the code in addition to the new autoloading
functionality.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Stop building scsi_dh as a separate module and integrate it fully into the
core SCSI code with explicit callouts at bus scan time. For now the
callouts are placed at the same point as the old bus notifiers were called,
but in the future we will be able to look at ALUA INQUIRY data earlier on.
Note that this also means that the device handler modules need to be loaded
by the time we scan the bus. The next patches will add support for
autoloading device handlers at bus scan time to make sure they are always
loaded if they are enabled in the kernel config.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Prepare for building scsi_dh.c into the core SCSI module by moving it to
drivers/scsi.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
