libnvdimm: Use max contiguous area for namespace size

This patch will find the max contiguous area to determine the largest
pmem namespace size that can be created. If the requested size exceeds
the largest available, ENOSPC error will be returned.

This fixes the allocation underrun error and wrong error return code
that have otherwise been observed as the following kernel warning:

  WARNING: CPU: <CPU> PID: <PID> at drivers/nvdimm/namespace_devs.c:913 size_store

Fixes: a1f3e4d6a0c3 ("libnvdimm, region: update nd_region_available_dpa() for multi-pmem support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index 79274ead54fb..ac68072fb8cd 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -100,6 +100,14 @@ struct nd_region;
 struct nvdimm_drvdata;
 struct nd_mapping;
 void nd_mapping_free_labels(struct nd_mapping *nd_mapping);
+
+int __reserve_free_pmem(struct device *dev, void *data);
+void release_free_pmem(struct nvdimm_bus *nvdimm_bus,
+		       struct nd_mapping *nd_mapping);
+
+resource_size_t nd_pmem_max_contiguous_dpa(struct nd_region *nd_region,
+					   struct nd_mapping *nd_mapping);
+resource_size_t nd_region_allocatable_dpa(struct nd_region *nd_region);
 resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
 		struct nd_mapping *nd_mapping, resource_size_t *overlap);
 resource_size_t nd_blk_available_dpa(struct nd_region *nd_region);