linux-kernel - [PATCH v18 11/19] cxl: Add features driver attribute to emit number of features supported

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250106121017.1620-12-shiju.jose@huawei.com>
Date: Mon, 6 Jan 2025 12:10:07 +0000
From: <shiju.jose@...wei.com>
To: <linux-edac@...r.kernel.org>, <linux-cxl@...r.kernel.org>,
	<linux-acpi@...r.kernel.org>, <linux-mm@...ck.org>,
	<linux-kernel@...r.kernel.org>
CC: <bp@...en8.de>, <tony.luck@...el.com>, <rafael@...nel.org>,
	<lenb@...nel.org>, <mchehab@...nel.org>, <dan.j.williams@...el.com>,
	<dave@...olabs.net>, <jonathan.cameron@...wei.com>, <dave.jiang@...el.com>,
	<alison.schofield@...el.com>, <vishal.l.verma@...el.com>,
	<ira.weiny@...el.com>, <david@...hat.com>, <Vilas.Sridharan@....com>,
	<leo.duran@....com>, <Yazen.Ghannam@....com>, <rientjes@...gle.com>,
	<jiaqiyan@...gle.com>, <Jon.Grimm@....com>, <dave.hansen@...ux.intel.com>,
	<naoya.horiguchi@....com>, <james.morse@....com>, <jthoughton@...gle.com>,
	<somasundaram.a@....com>, <erdemaktas@...gle.com>, <pgonda@...gle.com>,
	<duenwen@...gle.com>, <gthelen@...gle.com>, <wschwartz@...erecomputing.com>,
	<dferguson@...erecomputing.com>, <wbs@...amperecomputing.com>,
	<nifan.cxl@...il.com>, <yazen.ghannam@....com>, <tanxiaofei@...wei.com>,
	<prime.zeng@...ilicon.com>, <roberto.sassu@...wei.com>,
	<kangkang.shen@...urewei.com>, <wanghuiqiang@...wei.com>,
	<linuxarm@...wei.com>, <shiju.jose@...wei.com>
Subject: [PATCH v18 11/19] cxl: Add features driver attribute to emit number of features supported

From: Dave Jiang <dave.jiang@...el.com>

Enable sysfs attribute emission of the number of features supported by the
driver/device. This is useful for userspace to determine the number of features
to query for.

Signed-off-by: Dave Jiang <dave.jiang@...el.com>
---
 drivers/cxl/features.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/cxl/features.c b/drivers/cxl/features.c
index 2cdf5ed0a771..2f0fb072921e 100644
--- a/drivers/cxl/features.c
+++ b/drivers/cxl/features.c
@@ -173,11 +173,38 @@ static void cxl_features_remove(struct device *dev)
 	kfree(cfs);
 }
 
+static ssize_t features_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct cxl_features_state *cfs = dev_get_drvdata(dev);
+
+	if (!cfs)
+		return -ENOENT;
+
+	return sysfs_emit(buf, "%d\n", cfs->num_features);
+}
+
+static DEVICE_ATTR_RO(features);
+
+static struct attribute *cxl_features_attrs[] = {
+	&dev_attr_features.attr,
+	NULL
+};
+
+static struct attribute_group cxl_features_group = {
+	.attrs = cxl_features_attrs,
+};
+
+__ATTRIBUTE_GROUPS(cxl_features);
+
 static struct cxl_driver cxl_features_driver = {
 	.name = "cxl_features",
 	.probe = cxl_features_probe,
 	.remove = cxl_features_remove,
 	.id = CXL_DEVICE_FEATURES,
+	.drv = {
+		.dev_groups = cxl_features_groups,
+	},
 };
 
 module_cxl_driver(cxl_features_driver);
-- 
2.43.0