dm mpath: rdac

This patch supports LSI/Engenio devices in RDAC mode. Like dm-emc
it requires userspace support. In your multipath.conf file you must have:

path_checker            rdac
hardware_handler        "1 rdac"
prio_callout		"/sbin/mpath_prio_tpc /dev/%n"

And you also then must have a updated multipath tools release which
has rdac support.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 7df934d69134..466909f38d98 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -262,6 +262,12 @@ config DM_MULTIPATH_EMC
         ---help---
           Multipath support for EMC CX/AX series hardware.
 
+config DM_MULTIPATH_RDAC
+        tristate "LSI/Engenio RDAC multipath support (EXPERIMENTAL)"
+        depends on DM_MULTIPATH && BLK_DEV_DM && EXPERIMENTAL
+        ---help---
+          Multipath support for LSI/Engenio RDAC.
+
 config DM_DELAY
         tristate "I/O delaying target (EXPERIMENTAL)"
         depends on BLK_DEV_DM && EXPERIMENTAL