[PATCH 1/2] ns: Allow ns_entries to have custom symlink content

From: Kirill Tkhai
Date: Sat Jan 14 2017 - 09:15:16 EST


Make possible to have link content prefix yyy
different from the link name xxx:

$ readlink /proc/[pid]/ns/xxx
yyy:[4026531838]

This will be used in next patch.

Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
---
fs/nsfs.c | 4 +++-
include/linux/proc_ns.h | 1 +
2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/nsfs.c b/fs/nsfs.c
index 8c9fb29c6673..c2499c59bf51 100644
--- a/fs/nsfs.c
+++ b/fs/nsfs.c
@@ -182,9 +182,11 @@ int ns_get_name(char *buf, size_t size, struct task_struct *task,
{
struct ns_common *ns;
int res = -ENOENT;
+ const char *name;
ns = ns_ops->get(task);
if (ns) {
- res = snprintf(buf, size, "%s:[%u]", ns_ops->name, ns->inum);
+ name = ns_ops->real_ns_name ? : ns_ops->name;
+ res = snprintf(buf, size, "%s:[%u]", name, ns->inum);
ns_ops->put(ns);
}
return res;
diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
index 12cb8bd81d2d..88dba3b53375 100644
--- a/include/linux/proc_ns.h
+++ b/include/linux/proc_ns.h
@@ -14,6 +14,7 @@ struct inode;

struct proc_ns_operations {
const char *name;
+ const char *real_ns_name;
int type;
struct ns_common *(*get)(struct task_struct *task);
void (*put)(struct ns_common *ns);