From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Tue, 2 Feb 2021 12:46:03 +0000 (+0100)
Subject: cgroups: add unified_cgroup_fd() helper
X-Git-Tag: lxc-5.0.0~306^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6d15354365ef2312de5a08682b3e7e6e6b73e24f;p=thirdparty%2Flxc.git

cgroups: add unified_cgroup_fd() helper

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---

diff --git a/src/lxc/cgroups/cgroup_utils.c b/src/lxc/cgroups/cgroup_utils.c
index dc7813441..1ffc63fa9 100644
--- a/src/lxc/cgroups/cgroup_utils.c
+++ b/src/lxc/cgroups/cgroup_utils.c
@@ -98,3 +98,16 @@ int unified_cgroup_hierarchy(void)
 
 	return 0;
 }
+
+int unified_cgroup_fd(int fd)
+{
+
+	int ret;
+	struct statfs fs;
+
+	ret = fstatfs(fd, &fs);
+	if (!ret && is_fs_type(&fs, CGROUP2_SUPER_MAGIC))
+		return true;
+
+	return false;
+}
diff --git a/src/lxc/cgroups/cgroup_utils.h b/src/lxc/cgroups/cgroup_utils.h
index 17d7b2ffe..818eead1d 100644
--- a/src/lxc/cgroups/cgroup_utils.h
+++ b/src/lxc/cgroups/cgroup_utils.h
@@ -30,4 +30,6 @@ __hidden extern bool test_writeable_v2(char *mountpoint, char *path);
 
 __hidden extern int unified_cgroup_hierarchy(void);
 
+__hidden extern int unified_cgroup_fd(int fd);
+
 #endif /* __LXC_CGROUP_UTILS_H */