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/libnvdimm.h b/include/linux/libnvdimm.h
index 39e7e60..37f966a 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -71,8 +71,11 @@
struct nvdimm_bus;
struct device;
-struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
- struct nvdimm_bus_descriptor *nfit_desc);
+struct module;
+struct nvdimm_bus *__nvdimm_bus_register(struct device *parent,
+ struct nvdimm_bus_descriptor *nfit_desc, struct module *module);
+#define nvdimm_bus_register(parent, desc) \
+ __nvdimm_bus_register(parent, desc, THIS_MODULE)
void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus);
struct nvdimm_bus *to_nvdimm_bus(struct device *dev);
struct nvdimm *to_nvdimm(struct device *dev);
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) \
diff --git a/include/uapi/linux/ndctl.h b/include/uapi/linux/ndctl.h
index 3764091..174b637 100644
--- a/include/uapi/linux/ndctl.h
+++ b/include/uapi/linux/ndctl.h
@@ -177,8 +177,18 @@
#define ND_DEVICE_DIMM 1 /* nd_dimm: container for "config data" */
+#define ND_DEVICE_REGION_PMEM 2 /* nd_region: (parent of PMEM namespaces) */
+#define ND_DEVICE_REGION_BLK 3 /* nd_region: (parent of BLK namespaces) */
+#define ND_DEVICE_NAMESPACE_IO 4 /* legacy persistent memory */
+#define ND_DEVICE_NAMESPACE_PMEM 5 /* PMEM namespace (may alias with BLK) */
+#define ND_DEVICE_NAMESPACE_BLK 6 /* BLK namespace (may alias with PMEM) */
enum nd_driver_flags {
ND_DRIVER_DIMM = 1 << ND_DEVICE_DIMM,
+ ND_DRIVER_REGION_PMEM = 1 << ND_DEVICE_REGION_PMEM,
+ ND_DRIVER_REGION_BLK = 1 << ND_DEVICE_REGION_BLK,
+ ND_DRIVER_NAMESPACE_IO = 1 << ND_DEVICE_NAMESPACE_IO,
+ ND_DRIVER_NAMESPACE_PMEM = 1 << ND_DEVICE_NAMESPACE_PMEM,
+ ND_DRIVER_NAMESPACE_BLK = 1 << ND_DEVICE_NAMESPACE_BLK,
};
#endif /* __NDCTL_H__ */