From a6a8d9f87eb8510a8f53672ea87703f62185d75f Mon Sep 17 00:00:00 2001 From: Chandra Seetharaman Date: Thu, 1 May 2008 14:49:46 -0700 Subject: [SCSI] scsi_dh: add infrastructure for SCSI Device Handlers Some of the storage devices (that can be accessed through multiple paths), do need some special handling for 1. Activating the passive path of the storage access. 2. Decode and handle the special sense codes returned by the devices. 3. Handle the I/Os being sent to the passive path, especially during the device probe time. when accessed through multiple paths. As of today this special device handling is done at the dm-multipath layer using dm-handlers. That works well for (1); for (2) to be handled at dm layer, scsi sense information need to be exported from SCSI to dm-layer, which is not very attractive; (3) cannot be done at all at the dm layer. Device handler has been moved to SCSI mainly to handle (2) and (3) properly. Signed-off-by: Chandra Seetharaman Signed-off-by: Mike Anderson Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- include/scsi/scsi.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/scsi/scsi.h') diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h index 32742c4563d..2b5b9356c31 100644 --- a/include/scsi/scsi.h +++ b/include/scsi/scsi.h @@ -400,6 +400,7 @@ struct scsi_lun { #define SOFT_ERROR 0x2005 #define ADD_TO_MLQUEUE 0x2006 #define TIMEOUT_ERROR 0x2007 +#define SCSI_RETURN_NOT_HANDLED 0x2008 /* * Midlevel queue return values. -- cgit v1.2.3