[SCSI] scsi_dh: fix kconfig related build errors
Do not automatically "select" SCSI_DH for dm-multipath. If SCSI_DH
doesn't exist,just do not allow hardware handlers to be used.
Handle SCSI_DH being a module also. Make sure it doesn't allow DM_MULTIPATH
to be compiled in when SCSI_DH is a module.
[jejb: added comment for Kconfig syntax]
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index b4a3c7d..07d92c1 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -252,7 +252,11 @@
config DM_MULTIPATH
tristate "Multipath target"
depends on BLK_DEV_DM
- select SCSI_DH
+ # nasty syntax but means make DM_MULTIPATH independent
+ # of SCSI_DH if the latter isn't defined but if
+ # it is, DM_MULTIPATH must depend on it. We get a build
+ # error if SCSI_DH=m and DM_MULTIPATH=y
+ depends on SCSI_DH || !SCSI_DH
---help---
Allow volume managers to support multipath hardware.