nfit, libnvdimm: clarify "commands" vs "_DSMs"

Clarify the distinction between "commands", the ioctls userspace calls
to request the kernel take some action on a given dimm device, and
"_DSMs", the actual function numbers used in the firmware interface to
the DIMM.  _DSMs are ACPI specific whereas commands are Linux kernel
generic.

This is in preparation for breaking the 1:1 implicit relationship
between the kernel ioctl number space and the firmware specific function
numbers.

Cc: Jerry Hoemann <jerry.hoemann@hpe.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index c56f882..79a35a0 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -37,9 +37,9 @@
 
 	nvdimm = to_nvdimm(ndd->dev);
 
-	if (!nvdimm->dsm_mask)
+	if (!nvdimm->cmd_mask)
 		return -ENXIO;
-	if (!test_bit(ND_CMD_GET_CONFIG_DATA, nvdimm->dsm_mask))
+	if (!test_bit(ND_CMD_GET_CONFIG_DATA, &nvdimm->cmd_mask))
 		return -ENXIO;
 
 	return 0;
@@ -263,6 +263,12 @@
 }
 EXPORT_SYMBOL_GPL(nvdimm_name);
 
+unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
+{
+	return nvdimm->cmd_mask;
+}
+EXPORT_SYMBOL_GPL(nvdimm_cmd_mask);
+
 void *nvdimm_provider_data(struct nvdimm *nvdimm)
 {
 	if (nvdimm)
@@ -277,10 +283,10 @@
 	struct nvdimm *nvdimm = to_nvdimm(dev);
 	int cmd, len = 0;
 
-	if (!nvdimm->dsm_mask)
+	if (!nvdimm->cmd_mask)
 		return sprintf(buf, "\n");
 
-	for_each_set_bit(cmd, nvdimm->dsm_mask, BITS_PER_LONG)
+	for_each_set_bit(cmd, &nvdimm->cmd_mask, BITS_PER_LONG)
 		len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
 	len += sprintf(buf + len, "\n");
 	return len;
@@ -340,7 +346,7 @@
 
 struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
 		const struct attribute_group **groups, unsigned long flags,
-		unsigned long *dsm_mask)
+		unsigned long cmd_mask)
 {
 	struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
 	struct device *dev;
@@ -355,7 +361,7 @@
 	}
 	nvdimm->provider_data = provider_data;
 	nvdimm->flags = flags;
-	nvdimm->dsm_mask = dsm_mask;
+	nvdimm->cmd_mask = cmd_mask;
 	atomic_set(&nvdimm->busy, 0);
 	dev = &nvdimm->dev;
 	dev_set_name(dev, "nmem%d", nvdimm->id);