This new helper allows us to obtain the fd of a net_cls cgroup, which will
be utilized in the subsequent patch.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20231206115326.4295-3-laoar.shao@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
fclose(file);
return found ? id : -1;
}
fclose(file);
return found ? id : -1;
}
+
+/**
+ * open_classid() - Open a cgroupv1 net_cls classid
+ *
+ * This function expects the cgroup work dir to be already created, as we
+ * open it here.
+ *
+ * On success, it returns the file descriptor. On failure it returns -1.
+ */
+int open_classid(void)
+{
+ char cgroup_workdir[PATH_MAX + 1];
+
+ format_classid_path(cgroup_workdir);
+ return open(cgroup_workdir, O_RDONLY);
+}
int set_classid(void);
int join_classid(void);
unsigned long long get_classid_cgroup_id(void);
int set_classid(void);
int join_classid(void);
unsigned long long get_classid_cgroup_id(void);
int setup_classid_environment(void);
void cleanup_classid_environment(void);
int setup_classid_environment(void);
void cleanup_classid_environment(void);