[PATCH v2 08/12] libnvdimm: Refactor an nvdimm_lock_class() helper

[Dan Williams]

In preparation for moving to the device-core device_lock lockdep
validation, refactor an nvdimm_lock_class() helper to be used with
device_set_lock_class().

Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Cc: Dave Jiang <dave.jiang@xxxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
 drivers/nvdimm/nd-core.h |   21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index 448f9dcb4bb7..deb3d047571e 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -174,22 +174,27 @@ enum {
 	LOCK_CLAIM,
 };
 
-static inline void debug_nvdimm_lock(struct device *dev)
+static inline int nvdimm_lock_class(struct device *dev)
 {
 	if (is_nd_region(dev))
-		mutex_lock_nested(&dev->lockdep_mutex, LOCK_REGION);
+		return LOCK_REGION;
 	else if (is_nvdimm(dev))
-		mutex_lock_nested(&dev->lockdep_mutex, LOCK_DIMM);
+		return LOCK_DIMM;
 	else if (is_nd_btt(dev) || is_nd_pfn(dev) || is_nd_dax(dev))
-		mutex_lock_nested(&dev->lockdep_mutex, LOCK_CLAIM);
+		return LOCK_CLAIM;
 	else if (dev->parent && (is_nd_region(dev->parent)))
-		mutex_lock_nested(&dev->lockdep_mutex, LOCK_NAMESPACE);
+		return LOCK_NAMESPACE;
 	else if (is_nvdimm_bus(dev))
-		mutex_lock_nested(&dev->lockdep_mutex, LOCK_BUS);
+		return LOCK_BUS;
 	else if (dev->class && dev->class == nd_class)
-		mutex_lock_nested(&dev->lockdep_mutex, LOCK_NDCTL);
+		return LOCK_NDCTL;
 	else
-		dev_WARN(dev, "unknown lock level\n");
+		return -1;
+}
+
+static inline void debug_nvdimm_lock(struct device *dev)
+{
+	mutex_lock_nested(&dev->lockdep_mutex, nvdimm_lock_class(dev));
 }
 
 static inline void debug_nvdimm_unlock(struct device *dev)