From: Christian Brauner <brauner@kernel.org>
Date: Fri, 28 Jun 2024 08:05:19 +0000 (+0200)
Subject: nsproxy: add helper to go from arbitrary namespace to ns_common
X-Git-Tag: v6.11-rc1~234^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=85e4daaeb70bc68ec920e0c268eb428113d31b21;p=thirdparty%2Fkernel%2Fstable.git

nsproxy: add helper to go from arbitrary namespace to ns_common

They all contains struct ns_common ns and if there ever is one where
that isn't the case we'll catch it here at build time.

Signed-off-by: Christian Brauner <brauner@kernel.org>
---

diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h
index e6bec522b1391..dab6a1734a226 100644
--- a/include/linux/nsproxy.h
+++ b/include/linux/nsproxy.h
@@ -42,6 +42,17 @@ struct nsproxy {
 };
 extern struct nsproxy init_nsproxy;
 
+#define to_ns_common(__ns)                              \
+	_Generic((__ns),                                \
+		struct cgroup_namespace *: &(__ns->ns), \
+		struct ipc_namespace *:    &(__ns->ns), \
+		struct net *:              &(__ns->ns), \
+		struct pid_namespace *:    &(__ns->ns), \
+		struct mnt_namespace *:    &(__ns->ns), \
+		struct time_namespace *:   &(__ns->ns), \
+		struct user_namespace *:   &(__ns->ns), \
+		struct uts_namespace *:    &(__ns->ns))
+
 /*
  * A structure to encompass all bits needed to install
  * a partial or complete new set of namespaces.