[SCSI] scsi_dh: Reference count scsi_dh_attach
Problem reported: http://marc.info/?l=dm-devel&m=124585978305866&w=2
scsi_dh does not do a refernce count for attach/detach, and this affects
the way it is supposed to work with multipath when a device is not
in the dev_list of the hardware handler.
This patch adds a reference count that counts each attach.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 3f566af..1f3a4c8 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -191,6 +191,8 @@
struct scsi_dh_data {
struct scsi_device_handler *scsi_dh;
+ struct scsi_device *sdev;
+ struct kref kref;
char buf[0];
};