[CRIU] [PATCH v2 26/36] ns: Add ns_owner

[Kirill Tkhai]

Add a struct ns_id member to store information,
where the ns copy may be obtained.

It's "/proc/[pid]/fd/[fd]", or "/proc/[pid]/ns/[ns]"
in dependence of ns_owner::fd value.

Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
---
 criu/include/namespaces.h |    8 ++++++++
 criu/namespaces.c         |    2 ++
 2 files changed, 10 insertions(+)

diff --git a/criu/include/namespaces.h b/criu/include/namespaces.h
index 21dc8beb7..546de7c5d 100644
--- a/criu/include/namespaces.h
+++ b/criu/include/namespaces.h
@@ -81,6 +81,13 @@ enum ns_type {
 	NS_OTHER,
 };
 
+struct ns_owner {
+	struct {
+		pid_t pid;	/* Owner pid */
+		int fd; 	/* Owner fd, or -1 if it's /proc/[pid]/ns/[ns] file */
+	};
+};
+
 struct ns_id {
 	unsigned int kid;
 	unsigned int id;
@@ -90,6 +97,7 @@ struct ns_id {
 	struct list_head children;
 	struct list_head siblings;
 	struct ns_id *user_ns;
+	struct ns_owner owner;
 	struct ns_id *next;
 	enum ns_type type;
 
diff --git a/criu/namespaces.c b/criu/namespaces.c
index 538074ab9..6151219d8 100644
--- a/criu/namespaces.c
+++ b/criu/namespaces.c
@@ -302,6 +302,8 @@ struct ns_id *rst_new_ns_id(unsigned int id, pid_t pid,
 		nsid->type = type;
 		nsid_add(nsid, nd, id, pid);
 		nsid->ns_populated = false;
+		nsid->owner.pid = -1;
+		nsid->owner.fd = -1;
 		INIT_LIST_HEAD(&nsid->children);
 		INIT_LIST_HEAD(&nsid->siblings);
 	}