dax: introduce CONFIG_DAX_DRIVER

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 <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2018-03-29 17:20:39 -07:00
parent d2c997c0f1
commit 2080e88aec
3 changed files with 6 additions and 3 deletions

View File

@ -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

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@ -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

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@ -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