diff options
| author | Dan Williams | 2017-07-16 13:51:53 -0700 |
|---|---|---|
| committer | Dan Williams | 2019-01-06 21:41:57 -0800 |
| commit | 730926c3b0998943654019f00296cf8e3b02277e (patch) | |
| tree | 9bdff0b62f4a020427144de5b703048bfb1f7c16 /Documentation/ABI | |
| parent | d200781ef237a354d918ceff5cee350d88a93d42 (diff) | |
device-dax: Add /sys/class/dax backwards compatibility
On the expectation that some environments may not upgrade libdaxctl
(userspace component that depends on the /sys/class/dax hierarchy),
provide a default / legacy dax_pmem_compat driver. The dax_pmem_compat
driver implements the original /sys/class/dax sysfs layout rather than
/sys/bus/dax. When userspace is upgraded it can blacklist this module
and switch to the dax_pmem driver going forward.
CONFIG_DEV_DAX_PMEM_COMPAT and supporting code will be deleted according
to the dax_pmem entry in Documentation/ABI/obsolete/.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/obsolete/sysfs-class-dax | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/Documentation/ABI/obsolete/sysfs-class-dax b/Documentation/ABI/obsolete/sysfs-class-dax new file mode 100644 index 000000000000..2cb9fc5e8bd1 --- /dev/null +++ b/Documentation/ABI/obsolete/sysfs-class-dax @@ -0,0 +1,22 @@ +What: /sys/class/dax/ +Date: May, 2016 +KernelVersion: v4.7 +Contact: linux-nvdimm@lists.01.org +Description: Device DAX is the device-centric analogue of Filesystem + DAX (CONFIG_FS_DAX). It allows memory ranges to be + allocated and mapped without need of an intervening file + system. Device DAX is strict, precise and predictable. + Specifically this interface: + + 1/ Guarantees fault granularity with respect to a given + page size (pte, pmd, or pud) set at configuration time. + + 2/ Enforces deterministic behavior by being strict about + what fault scenarios are supported. + + The /sys/class/dax/ interface enumerates all the + device-dax instances in the system. The ABI is + deprecated and will be removed after 2020. It is + replaced with the DAX bus interface /sys/bus/dax/ where + device-dax instances can be found under + /sys/bus/dax/devices/ |