[PATCH 14/14] time_namespace: always provide arch_get_vdso_data() prototype for vdso

From: Arnd Bergmann
Date: Wed May 17 2023 - 09:13:59 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

The arch_get_vdso_data() function is defined separately on each architecture,
but only called when CONFIG_TIME_NS is set. If the definition is a global
function, this causes a W=1 warning without TIME_NS:

arch/x86/entry/vdso/vma.c:35:19: error: no previous prototype for 'arch_get_vdso_data' [-Werror=missing-prototypes]

Move the prototype out of the #ifdef block to reliably turn off that
warning.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
include/linux/time_namespace.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h
index bb9d3f5542f8..03d9c5ac01d1 100644
--- a/include/linux/time_namespace.h
+++ b/include/linux/time_namespace.h
@@ -44,7 +44,6 @@ struct time_namespace *copy_time_ns(unsigned long flags,
struct time_namespace *old_ns);
void free_time_ns(struct time_namespace *ns);
void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
-struct vdso_data *arch_get_vdso_data(void *vvar_page);
struct page *find_timens_vvar_page(struct vm_area_struct *vma);

static inline void put_time_ns(struct time_namespace *ns)
@@ -163,4 +162,6 @@ static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim)
}
#endif

+struct vdso_data *arch_get_vdso_data(void *vvar_page);
+
#endif /* _LINUX_TIMENS_H */
--
2.39.2