[RFC PATCH 12/46] liveupdate: Add liveupdate_session_name() helper

[Pasha Tatashin]

Provide an accessor function liveupdate_session_name() to retrieve the
name of a live update session from its session handle.

This allows kernel subsystems like CPU preservation to identify the
session managing preserved resources.

Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
---
 include/linux/liveupdate.h      |  6 ++++++
 kernel/liveupdate/luo_session.c | 14 ++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/include/linux/liveupdate.h b/include/linux/liveupdate.h
index 6051abc0612c..119ad0f82705 100644
--- a/include/linux/liveupdate.h
+++ b/include/linux/liveupdate.h
@@ -256,6 +256,7 @@ int liveupdate_get_file_incoming(struct liveupdate_session *s, u64 token,
 /* Get a token for an outgoing file, or -ENOENT if file is not preserved */
 int liveupdate_get_token_outgoing(struct liveupdate_session *s,
 				  struct file *file, u64 *tokenp);
+const char *liveupdate_session_name(struct liveupdate_session *s);
 
 #else /* CONFIG_LIVEUPDATE */
 
@@ -321,5 +322,10 @@ static inline int liveupdate_get_token_outgoing(struct liveupdate_session *s,
 	return -EOPNOTSUPP;
 }
 
+static inline const char *liveupdate_session_name(struct liveupdate_session *s)
+{
+	return NULL;
+}
+
 #endif /* CONFIG_LIVEUPDATE */
 #endif /* _LINUX_LIVEUPDATE_H */
diff --git a/kernel/liveupdate/luo_session.c b/kernel/liveupdate/luo_session.c
index f48e9a4185f9..3c4f195d375d 100644
--- a/kernel/liveupdate/luo_session.c
+++ b/kernel/liveupdate/luo_session.c
@@ -683,3 +683,17 @@ int luo_session_serialize(void)
 
 	return err;
 }
+
+/**
+ * liveupdate_session_name - Get the name of a liveupdate session
+ * @s: Live update session pointer.
+ *
+ * Return: Pointer to session name string.
+ */
+const char *liveupdate_session_name(struct liveupdate_session *s)
+{
+	struct luo_session *session = (struct luo_session *)s;
+
+	return session->name;
+}
+EXPORT_SYMBOL_GPL(liveupdate_session_name);
-- 
2.55.0.1082.g2b9226bbc0-goog