Merge tag 'libnvdimm-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm update from Dan Williams:
 "A single cleanup that precedes some deeper PMEM/DAX reworks that did
  not settle in time for v5.16:

   - Continue the cleanup of the dax api in preparation for a dax-device
     block-device divorce"

* tag 'libnvdimm-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  nvdimm/pmem: move dax_attribute_group from dax to pmem

1 files changed, 43 insertions, 0 deletions

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 37fc03058556..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,