libnvdimm: support for legacy (non-aliasing) nvdimms
The libnvdimm region driver is an intermediary driver that translates
non-volatile "region"s into "namespace" sub-devices that are surfaced by
persistent memory block-device drivers (PMEM and BLK).
ACPI 6 introduces the concept that a given nvdimm may simultaneously
offer multiple access modes to its media through direct PMEM load/store
access, or windowed BLK mode. Existing nvdimms mostly implement a PMEM
interface, some offer a BLK-like mode, but never both as ACPI 6 defines.
If an nvdimm is single interfaced, then there is no need for dimm
metadata labels. For these devices we can take the region boundaries
directly to create a child namespace device (nd_namespace_io).
Acked-by: Christoph Hellwig <hch@lst.de>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/include/linux/nd.h b/include/linux/nd.h
index e074f67..da70e99 100644
--- a/include/linux/nd.h
+++ b/include/linux/nd.h
@@ -26,6 +26,16 @@
struct device_driver *drv)
{
return container_of(drv, struct nd_device_driver, drv);
+};
+
+struct nd_namespace_io {
+ struct device dev;
+ struct resource res;
+};
+
+static inline struct nd_namespace_io *to_nd_namespace_io(struct device *dev)
+{
+ return container_of(dev, struct nd_namespace_io, dev);
}
#define MODULE_ALIAS_ND_DEVICE(type) \