vdso/datastore: Gate time data behind CONFIG_GENERIC_GETTIMEOFDAY

When the generic vDSO does not provide time functions, as for example on
riscv32, then the time data store is not necessary.

Avoid allocating these time data pages when not used.

Fixes: df7fcbefa710 ("vdso: Add generic time data storage")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250826-vdso-cleanups-v1-1-d9b65750e49f@linutronix.de

diff --git a/lib/vdso/datastore.c b/lib/vdso/datastore.c
index 3693c6c..a565c30 100644 (file)
--- a/lib/vdso/datastore.c
+++ b/lib/vdso/datastore.c
@@ -11,14 +11,14 @@
 /*
  * The vDSO data page.
  */
-#ifdef CONFIG_HAVE_GENERIC_VDSO
+#ifdef CONFIG_GENERIC_GETTIMEOFDAY
 static union {
        struct vdso_time_data   data;
        u8                      page[PAGE_SIZE];
 } vdso_time_data_store __page_aligned_data;
 struct vdso_time_data *vdso_k_time_data = &vdso_time_data_store.data;
 static_assert(sizeof(vdso_time_data_store) == PAGE_SIZE);
-#endif /* CONFIG_HAVE_GENERIC_VDSO */
+#endif /* CONFIG_GENERIC_GETTIMEOFDAY */
 
 #ifdef CONFIG_VDSO_GETRANDOM
 static union {
@@ -46,7 +46,7 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
 
        switch (vmf->pgoff) {
        case VDSO_TIME_PAGE_OFFSET:
-               if (!IS_ENABLED(CONFIG_HAVE_GENERIC_VDSO))
+               if (!IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY))
                        return VM_FAULT_SIGBUS;
                pfn = __phys_to_pfn(__pa_symbol(vdso_k_time_data));
                if (timens_page) {