In support of allowing device-mapper to compile out idle/dead code when
there are no dax providers in the system, introduce the DAX_DRIVER
symbol. This is selected by all leaf drivers that device-mapper might be
layered on top. This allows device-mapper to conditionally 'select DAX'
only when a provider is present.
Cc: Martin Schwidefsky <schwidef...@de.ibm.com>
Cc: Heiko Carstens <heiko.carst...@de.ibm.com>
Reported-by: Bart Van Assche <bart.vanass...@wdc.com>
Reviewed-by: Mike Snitzer <snit...@redhat.com>
Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
---
drivers/dax/Kconfig | 5 ++++-
drivers/nvdimm/Kconfig | 2 +-
drivers/s390/block/Kconfig | 2 +-
3 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
index b79aa8f7a497..e0700bf4893a 100644
--- a/drivers/dax/Kconfig
+++ b/drivers/dax/Kconfig
@@ -1,3 +1,7 @@
+config DAX_DRIVER
+ select DAX
+ bool
+
menuconfig DAX
tristate "DAX: direct access to differentiated memory"
select SRCU
@@ -16,7 +20,6 @@ config DEV_DAX
baseline memory pool. Mappings of a /dev/daxX.Y device impose
restrictions that make the mapping behavior deterministic.
-
config DEV_DAX_PMEM
tristate "PMEM DAX: direct access to persistent memory"
depends on LIBNVDIMM && NVDIMM_DAX && DEV_DAX
diff --git a/drivers/nvdimm/Kconfig b/drivers/nvdimm/Kconfig
index a65f2e1d9f53..40cbdb16e23e 100644
--- a/drivers/nvdimm/Kconfig
+++ b/drivers/nvdimm/Kconfig
@@ -20,7 +20,7 @@ if LIBNVDIMM
config BLK_DEV_PMEM
tristate "PMEM: Persistent memory block device support"
default LIBNVDIMM
- select DAX
+ select DAX_DRIVER
select ND_BTT if BTT
select ND_PFN if NVDIMM_PFN
help
diff --git a/drivers/s390/block/Kconfig b/drivers/s390/block/Kconfig
index 1444333210c7..9ac7574e3cfb 100644
--- a/drivers/s390/block/Kconfig
+++ b/drivers/s390/block/Kconfig
@@ -15,8 +15,8 @@ config BLK_DEV_XPRAM
config DCSSBLK
def_tristate m
- select DAX
select FS_DAX_LIMITED
+ select DAX_DRIVER
prompt "DCSSBLK support"
depends on S390 && BLOCK
help
