libnvdimm: blk labels and namespace instantiation
A blk label set describes a namespace comprised of one or more
discontiguous dpa ranges on a single dimm. They may alias with one or
more pmem interleave sets that include the given dimm.
This is the runtime/volatile configuration infrastructure for sysfs
manipulation of 'alt_name', 'uuid', 'size', and 'sector_size'. A later
patch will make these settings persistent by writing back the label(s).
Unlike pmem namespaces, multiple blk namespaces can be created per
region. Once a blk namespace has been created a new seed device
(unconfigured child of a parent blk region) is instantiated. As long as
a region has 'available_size' != 0 new child namespaces may be created.
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index b55acef..101d3b7 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -290,6 +290,42 @@
EXPORT_SYMBOL_GPL(nvdimm_create);
/**
+ * nd_blk_available_dpa - account the unused dpa of BLK region
+ * @nd_mapping: container of dpa-resource-root + labels
+ *
+ * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges.
+ */
+resource_size_t nd_blk_available_dpa(struct nd_mapping *nd_mapping)
+{
+ struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+ resource_size_t map_end, busy = 0, available;
+ struct resource *res;
+
+ if (!ndd)
+ return 0;
+
+ map_end = nd_mapping->start + nd_mapping->size - 1;
+ for_each_dpa_resource(ndd, res)
+ if (res->start >= nd_mapping->start && res->start < map_end) {
+ resource_size_t end = min(map_end, res->end);
+
+ busy += end - res->start + 1;
+ } else if (res->end >= nd_mapping->start
+ && res->end <= map_end) {
+ busy += res->end - nd_mapping->start;
+ } else if (nd_mapping->start > res->start
+ && nd_mapping->start < res->end) {
+ /* total eclipse of the BLK region mapping */
+ busy += nd_mapping->size;
+ }
+
+ available = map_end - nd_mapping->start + 1;
+ if (busy < available)
+ return available - busy;
+ return 0;
+}
+
+/**
* nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
* @nd_mapping: container of dpa-resource-root + labels
* @nd_region: constrain available space check to this reference region