Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
index 795ad4f..3508a79 100644
--- a/drivers/nvdimm/btt_devs.c
+++ b/drivers/nvdimm/btt_devs.c
@@ -1,14 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
  */
 #include <linux/blkdev.h>
 #include <linux/device.h>
@@ -70,14 +62,14 @@
 	struct nd_btt *nd_btt = to_nd_btt(dev);
 	ssize_t rc;
 
-	device_lock(dev);
+	nd_device_lock(dev);
 	nvdimm_bus_lock(dev);
 	rc = nd_size_select_store(dev, buf, &nd_btt->lbasize,
 			btt_lbasize_supported);
 	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
 			buf[len - 1] == '\n' ? "" : "\n");
 	nvdimm_bus_unlock(dev);
-	device_unlock(dev);
+	nd_device_unlock(dev);
 
 	return rc ? rc : len;
 }
@@ -99,11 +91,11 @@
 	struct nd_btt *nd_btt = to_nd_btt(dev);
 	ssize_t rc;
 
-	device_lock(dev);
+	nd_device_lock(dev);
 	rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len);
 	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
 			buf[len - 1] == '\n' ? "" : "\n");
-	device_unlock(dev);
+	nd_device_unlock(dev);
 
 	return rc ? rc : len;
 }
@@ -128,13 +120,13 @@
 	struct nd_btt *nd_btt = to_nd_btt(dev);
 	ssize_t rc;
 
-	device_lock(dev);
+	nd_device_lock(dev);
 	nvdimm_bus_lock(dev);
 	rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
 	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
 			buf[len - 1] == '\n' ? "" : "\n");
 	nvdimm_bus_unlock(dev);
-	device_unlock(dev);
+	nd_device_unlock(dev);
 
 	return rc;
 }
@@ -146,24 +138,32 @@
 	struct nd_btt *nd_btt = to_nd_btt(dev);
 	ssize_t rc;
 
-	device_lock(dev);
+	nd_device_lock(dev);
 	if (dev->driver)
 		rc = sprintf(buf, "%llu\n", nd_btt->size);
 	else {
 		/* no size to convey if the btt instance is disabled */
 		rc = -ENXIO;
 	}
-	device_unlock(dev);
+	nd_device_unlock(dev);
 
 	return rc;
 }
 static DEVICE_ATTR_RO(size);
 
+static ssize_t log_zero_flags_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "Y\n");
+}
+static DEVICE_ATTR_RO(log_zero_flags);
+
 static struct attribute *nd_btt_attributes[] = {
 	&dev_attr_sector_size.attr,
 	&dev_attr_namespace.attr,
 	&dev_attr_uuid.attr,
 	&dev_attr_size.attr,
+	&dev_attr_log_zero_flags.attr,
 	NULL,
 };
 
@@ -190,14 +190,15 @@
 		return NULL;
 
 	nd_btt->id = ida_simple_get(&nd_region->btt_ida, 0, 0, GFP_KERNEL);
-	if (nd_btt->id < 0) {
-		kfree(nd_btt);
-		return NULL;
-	}
+	if (nd_btt->id < 0)
+		goto out_nd_btt;
 
 	nd_btt->lbasize = lbasize;
-	if (uuid)
+	if (uuid) {
 		uuid = kmemdup(uuid, 16, GFP_KERNEL);
+		if (!uuid)
+			goto out_put_id;
+	}
 	nd_btt->uuid = uuid;
 	dev = &nd_btt->dev;
 	dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
@@ -212,6 +213,13 @@
 		return NULL;
 	}
 	return dev;
+
+out_put_id:
+	ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
+
+out_nd_btt:
+	kfree(nd_btt);
+	return NULL;
 }
 
 struct device *nd_btt_create(struct nd_region *nd_region)