1 files changed, 59 insertions, 5 deletions

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index c74d7bceb222..fe7ece1534e1 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -327,6 +327,49 @@ static const struct dax_operations pmem_dax_ops = {
 	.zero_page_range = pmem_dax_zero_page_range,
 };
 
+static ssize_t write_cache_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct pmem_device *pmem = dev_to_disk(dev)->private_data;
+
+	return sprintf(buf, "%d\n", !!dax_write_cache_enabled(pmem->dax_dev));
+}
+
+static ssize_t write_cache_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct pmem_device *pmem = dev_to_disk(dev)->private_data;
+	bool write_cache;
+	int rc;
+
+	rc = strtobool(buf, &write_cache);
+	if (rc)
+		return rc;
+	dax_write_cache(pmem->dax_dev, write_cache);
+	return len;
+}
+static DEVICE_ATTR_RW(write_cache);
+
+static umode_t dax_visible(struct kobject *kobj, struct attribute *a, int n)
+{
+#ifndef CONFIG_ARCH_HAS_PMEM_API
+	if (a == &dev_attr_write_cache.attr)
+		return 0;
+#endif
+	return a->mode;
+}
+
+static struct attribute *dax_attributes[] = {
+	&dev_attr_write_cache.attr,
+	NULL,
+};
+
+static const struct attribute_group dax_attribute_group = {
+	.name		= "dax",
+	.attrs		= dax_attributes,
+	.is_visible	= dax_visible,
+};
+
 static const struct attribute_group *pmem_attribute_groups[] = {
 	&dax_attribute_group,
 	NULL,
@@ -428,8 +471,10 @@ static int pmem_attach_disk(struct device *dev,
 		bb_range.end = res->end;
 	}
 
-	if (IS_ERR(addr))
-		return PTR_ERR(addr);
+	if (IS_ERR(addr)) {
+		rc = PTR_ERR(addr);
+		goto out;
+	}
 	pmem->virt_addr = addr;
 
 	blk_queue_write_cache(q, true, fua);
@@ -454,12 +499,15 @@ static int pmem_attach_disk(struct device *dev,
 		flags = DAXDEV_F_SYNC;
 	dax_dev = alloc_dax(pmem, disk->disk_name, &pmem_dax_ops, flags);
 	if (IS_ERR(dax_dev)) {
-		return PTR_ERR(dax_dev);
+		rc = PTR_ERR(dax_dev);
+		goto out;
 	}
 	dax_write_cache(dax_dev, nvdimm_has_cache(nd_region));
 	pmem->dax_dev = dax_dev;
 
-	device_add_disk(dev, disk, pmem_attribute_groups);
+	rc = device_add_disk(dev, disk, pmem_attribute_groups);
+	if (rc)
+		goto out_cleanup_dax;
 	if (devm_add_action_or_reset(dev, pmem_release_disk, pmem))
 		return -ENOMEM;
 
@@ -469,8 +517,14 @@ static int pmem_attach_disk(struct device *dev,
 					  "badblocks");
 	if (!pmem->bb_state)
 		dev_warn(dev, "'badblocks' notification disabled\n");
-
 	return 0;
+
+out_cleanup_dax:
+	kill_dax(pmem->dax_dev);
+	put_dax(pmem->dax_dev);
+out:
+	blk_cleanup_disk(pmem->disk);
+	return rc;
 }
 
 static int nd_pmem_probe(struct device *dev)