]> git.baikalelectronics.ru Git - kernel.git/commit
[SCSI] scsi_dh: add infrastructure for SCSI Device Handlers
authorChandra Seetharaman <sekharan@us.ibm.com>
Thu, 1 May 2008 21:49:46 +0000 (14:49 -0700)
committerJames Bottomley <James.Bottomley@HansenPartnership.com>
Thu, 5 Jun 2008 14:23:40 +0000 (09:23 -0500)
commit1a336fd0119ea1fb099203348fe00a710991434e
treed166e14e3c035ae0e0f26329b2b3b0495046d234
parent8927281c24c2ffc9d6de3ce940ae7ae2f1494a41
[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 <sekharan@us.ibm.com>
Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
drivers/scsi/Kconfig
drivers/scsi/Makefile
drivers/scsi/device_handler/Kconfig [new file with mode: 0644]
drivers/scsi/device_handler/Makefile [new file with mode: 0644]
drivers/scsi/device_handler/scsi_dh.c [new file with mode: 0644]
drivers/scsi/scsi_error.c
drivers/scsi/scsi_lib.c
drivers/scsi/scsi_sysfs.c
include/scsi/scsi.h
include/scsi/scsi_device.h
include/scsi/scsi_dh.h [new file with mode: 0644]