libnvdimm, pmem: 'struct page' for pmem
Enable the pmem driver to handle PFN device instances. Attaching a pmem
namespace to a pfn device triggers the driver to allocate and initialize
struct page entries for pmem. Memory capacity for this allocation comes
exclusively from RAM for now which is suitable for low PMEM to RAM
ratios. This mechanism will be expanded later for setting an "allocate
from PMEM" policy.
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index 8da2be1..83e5d09 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -217,6 +217,7 @@
int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata);
bool is_nd_pfn(struct device *dev);
struct device *nd_pfn_create(struct nd_region *nd_region);
+int nd_pfn_validate(struct nd_pfn *nd_pfn);
#else
static inline int nd_pfn_probe(struct nd_namespace_common *ndns, void *drvdata)
{
@@ -232,6 +233,11 @@
{
return NULL;
}
+
+static inline int nd_pfn_validate(struct nd_pfn *nd_pfn)
+{
+ return -ENODEV;
+}
#endif
struct nd_region *to_nd_region(struct device *dev);