libnvdimm, pfn: 'struct page' provider infrastructure
Implement the base infrastructure for libnvdimm PFN devices. Similar to
BTT devices they take a namespace as a backing device and layer
functionality on top. In this case the functionality is reserving space
for an array of 'struct page' entries to be handed out through
pfn_to_page(). For now this is just the basic libnvdimm-device-model for
configuring the base PFN device.
As the namespace claiming mechanism for PFN devices is mostly identical
to BTT devices drivers/nvdimm/claim.c is created to house the common
bits.
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index 7384455..da43381 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -345,6 +345,23 @@
}
static DEVICE_ATTR_RO(btt_seed);
+static ssize_t pfn_seed_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct nd_region *nd_region = to_nd_region(dev);
+ ssize_t rc;
+
+ nvdimm_bus_lock(dev);
+ if (nd_region->pfn_seed)
+ rc = sprintf(buf, "%s\n", dev_name(nd_region->pfn_seed));
+ else
+ rc = sprintf(buf, "\n");
+ nvdimm_bus_unlock(dev);
+
+ return rc;
+}
+static DEVICE_ATTR_RO(pfn_seed);
+
static ssize_t read_only_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -373,6 +390,7 @@
&dev_attr_nstype.attr,
&dev_attr_mappings.attr,
&dev_attr_btt_seed.attr,
+ &dev_attr_pfn_seed.attr,
&dev_attr_read_only.attr,
&dev_attr_set_cookie.attr,
&dev_attr_available_size.attr,
@@ -744,6 +762,7 @@
nd_region->numa_node = ndr_desc->numa_node;
ida_init(&nd_region->ns_ida);
ida_init(&nd_region->btt_ida);
+ ida_init(&nd_region->pfn_ida);
dev = &nd_region->dev;
dev_set_name(dev, "region%d", nd_region->id);
dev->parent = &nvdimm_bus->dev;