[PATCH 07/11] 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.ve...@intel.com>
Cc: Dave Jiang <dave.ji...@intel.com>
Cc: Ira Weiny <ira.we...@intel.com>
Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
---
 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 2650a852eeaf..772568ffb9d6 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -197,22 +197,27 @@ 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)