libnvdimm, dax: introduce device-dax infrastructure
Device DAX is the device-centric analogue of Filesystem DAX
(CONFIG_FS_DAX). It allows persistent memory ranges to be allocated and
mapped without need of an intervening file system. This initial
infrastructure arranges for a libnvdimm pfn-device to be represented as
a different device-type so that it can be attached to a driver other
than the pmem driver.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 19f822d..97589e3 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -40,6 +40,8 @@
return ND_DEVICE_REGION_PMEM;
else if (is_nd_blk(dev))
return ND_DEVICE_REGION_BLK;
+ else if (is_nd_dax(dev))
+ return ND_DEVICE_DAX_PMEM;
else if (is_nd_pmem(dev->parent) || is_nd_blk(dev->parent))
return nd_region_to_nstype(to_nd_region(dev->parent));
@@ -246,6 +248,8 @@
void __nd_device_register(struct device *dev)
{
+ if (!dev)
+ return;
dev->bus = &nvdimm_bus_type;
get_device(dev);
async_schedule_domain(nd_async_device_register, dev,