dax: convert devm_create_dax_dev to PTR_ERR

For sub-division support we need access to the dax_dev created by
devm_create_dax_dev().

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

3 files changed, 16 insertions, 10 deletions

diff --git a/drivers/dax/dax.c b/drivers/dax/dax.c
index 03bb54f7f58f..e7d8a3902437 100644
--- a/drivers/dax/dax.c
+++ b/drivers/dax/dax.c
@@ -558,8 +558,8 @@ static void unregister_dax_dev(void *dev)
         device_unregister(dev);
 }
 
-int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
-                int count)
+struct dax_dev *devm_create_dax_dev(struct dax_region *dax_region,
+                struct resource *res, int count)
 {
         struct device *parent = dax_region->dev;
         struct dax_dev *dax_dev;
@@ -570,7 +570,7 @@ int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
 
         dax_dev = kzalloc(sizeof(*dax_dev) + sizeof(*res) * count, GFP_KERNEL);
         if (!dax_dev)
-                return -ENOMEM;
+                return ERR_PTR(-ENOMEM);
 
         for (i = 0; i < count; i++) {
                 if (!IS_ALIGNED(res[i].start, dax_region->align)
@@ -632,10 +632,14 @@ int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
         rc = device_add(dev);
         if (rc) {
                 put_device(dev);
-                return rc;
+                return ERR_PTR(rc);
         }
 
-        return devm_add_action_or_reset(dax_region->dev, unregister_dax_dev, dev);
+        rc = devm_add_action_or_reset(dax_region->dev, unregister_dax_dev, dev);
+        if (rc)
+                return ERR_PTR(rc);
+
+        return dax_dev;
 
  err_cdev:
         iput(dax_dev->inode);
@@ -646,7 +650,7 @@ int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
  err_id:
         kfree(dax_dev);
 
-        return rc;
+        return ERR_PTR(rc);
 }
 EXPORT_SYMBOL_GPL(devm_create_dax_dev);
 
diff --git a/drivers/dax/dax.h b/drivers/dax/dax.h
index d8b8f1f25054..ddd829ab58c0 100644
--- a/drivers/dax/dax.h
+++ b/drivers/dax/dax.h
@@ -13,12 +13,13 @@
 #ifndef __DAX_H__
 #define __DAX_H__
 struct device;
+struct dax_dev;
 struct resource;
 struct dax_region;
 void dax_region_put(struct dax_region *dax_region);
 struct dax_region *alloc_dax_region(struct device *parent,
                 int region_id, struct resource *res, unsigned int align,
                 void *addr, unsigned long flags);
-int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
-                int count);
+struct dax_dev *devm_create_dax_dev(struct dax_region *dax_region,
+                struct resource *res, int count);
 #endif /* __DAX_H__ */
diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c
index 59b75c5972bb..c24d32ec9ce6 100644
--- a/drivers/dax/pmem.c
+++ b/drivers/dax/pmem.c
@@ -61,6 +61,7 @@ static int dax_pmem_probe(struct device *dev)
         int rc;
         void *addr;
         struct resource res;
+        struct dax_dev *dax_dev;
         struct nd_pfn_sb *pfn_sb;
         struct dax_pmem *dax_pmem;
         struct nd_region *nd_region;
@@ -123,12 +124,12 @@ static int dax_pmem_probe(struct device *dev)
                 return -ENOMEM;
 
         /* TODO: support for subdividing a dax region... */
-        rc = devm_create_dax_dev(dax_region, &res, 1);
+        dax_dev = devm_create_dax_dev(dax_region, &res, 1);
 
         /* child dax_dev instances now own the lifetime of the dax_region */
         dax_region_put(dax_region);
 
-        return rc;
+        return PTR_ERR_OR_ZERO(dax_dev);
 }
 
 static struct nd_device_driver dax_pmem_driver = {