[RESEND,2/2] cxl: Add decoders_committed sysfs attribute to cxl_port

Commit Message

Dave Jiang Oct. 4, 2023, 10:03 p.m. UTC

This attribute allows cxl-cli to determine whether there are decoders
committed to a memdev.  This is only a snapshot of the state, and
doesn't offer any protection or serialization against a concurrent
disable-region operation.

Suggested-by: Dan Williams <[e-mail]>
Signed-off-by: Dave Jiang <[e-mail]>
---
 drivers/cxl/core/port.c |   25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

Patch

diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 16efb68eacfa..284d37f71bc6 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -527,8 +527,33 @@  static void cxl_port_release(struct device *dev)
 	kfree(port);
 }
 
+static ssize_t decoders_committed_show(struct device *dev,
+				       struct device_attribute *attr, char *buf)
+{
+	struct cxl_port *port = to_cxl_port(dev);
+	int rc;
+
+	down_read(&cxl_dpa_rwsem);
+	rc = sysfs_emit(buf, "%d\n", cxl_decoders_committed(port));
+	up_read(&cxl_dpa_rwsem);
+
+	return rc;
+}
+
+static DEVICE_ATTR_RO(decoders_committed);
+
+static struct attribute *cxl_port_attrs[] = {
+	&dev_attr_decoders_committed.attr,
+	NULL,
+};
+
+static struct attribute_group cxl_port_attribute_group = {
+	.attrs = cxl_port_attrs,
+};
+
 static const struct attribute_group *cxl_port_attribute_groups[] = {
 	&cxl_base_attribute_group,
+	&cxl_port_attribute_group,
 	NULL,
 };