vdso: Rework struct vdso_time_data and introduce struct vdso_clock

To support multiple PTP clocks, the VDSO data structure needs to be
reworked. All clock specific data will end up in struct vdso_clock and in
struct vdso_time_data there will be an array of VDSO clocks.

Now that all preparatory changes are in place:

Split the clock related struct members into a separate struct
vdso_clock. Make sure all users are aware, that vdso_time_data is no longer
initialized as an array and vdso_clock is now the array inside
vdso_data. Remove the vdso_clock define, which mapped it to vdso_time_data
for the transition.

Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250303-vdso-clock-v1-19-c1b5c69a166f@linutronix.de

2 files changed, 10 insertions, 10 deletions

diff --git a/lib/vdso/datastore.c b/lib/vdso/datastore.c
index 4e350f56ace3..c715e217ec65 100644
--- a/lib/vdso/datastore.c
+++ b/lib/vdso/datastore.c
@@ -13,10 +13,10 @@
  */
 #ifdef CONFIG_HAVE_GENERIC_VDSO
 static union {
-	struct vdso_time_data	data[CS_BASES];
+	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;
+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 */
 
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index c6ff69345586..93ef801a97ef 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -87,8 +87,8 @@ int do_hres_timens(const struct vdso_time_data *vdns, const struct vdso_clock *v
 {
 	const struct vdso_time_data *vd = __arch_get_vdso_u_timens_data(vdns);
 	const struct timens_offset *offs = &vcns->offset[clk];
+	const struct vdso_clock *vc = vd->clock_data;
 	const struct vdso_timestamp *vdso_ts;
-	const struct vdso_clock *vc = vd;
 	u64 cycles, ns;
 	u32 seq;
 	s64 sec;
@@ -199,8 +199,8 @@ int do_coarse_timens(const struct vdso_time_data *vdns, const struct vdso_clock
 {
 	const struct vdso_time_data *vd = __arch_get_vdso_u_timens_data(vdns);
 	const struct timens_offset *offs = &vcns->offset[clk];
+	const struct vdso_clock *vc = vd->clock_data;
 	const struct vdso_timestamp *vdso_ts;
-	const struct vdso_clock *vc = vd;
 	u64 nsec;
 	s64 sec;
 	s32 seq;
@@ -265,7 +265,7 @@ static __always_inline int
 __cvdso_clock_gettime_common(const struct vdso_time_data *vd, clockid_t clock,
 			     struct __kernel_timespec *ts)
 {
-	const struct vdso_clock *vc = vd;
+	const struct vdso_clock *vc = vd->clock_data;
 	u32 msk;
 
 	/* Check for negative values or invalid clocks */
@@ -337,7 +337,7 @@ static __maybe_unused int
 __cvdso_gettimeofday_data(const struct vdso_time_data *vd,
 			  struct __kernel_old_timeval *tv, struct timezone *tz)
 {
-	const struct vdso_clock *vc = vd;
+	const struct vdso_clock *vc = vd->clock_data;
 
 	if (likely(tv != NULL)) {
 		struct __kernel_timespec ts;
@@ -371,13 +371,13 @@ __cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
 static __maybe_unused __kernel_old_time_t
 __cvdso_time_data(const struct vdso_time_data *vd, __kernel_old_time_t *time)
 {
-	const struct vdso_clock *vc = vd;
+	const struct vdso_clock *vc = vd->clock_data;
 	__kernel_old_time_t t;
 
 	if (IS_ENABLED(CONFIG_TIME_NS) &&
 	    vc->clock_mode == VDSO_CLOCKMODE_TIMENS) {
 		vd = __arch_get_vdso_u_timens_data(vd);
-		vc = vd;
+		vc = vd->clock_data;
 	}
 
 	t = READ_ONCE(vc[CS_HRES_COARSE].basetime[CLOCK_REALTIME].sec);
@@ -399,7 +399,7 @@ static __maybe_unused
 int __cvdso_clock_getres_common(const struct vdso_time_data *vd, clockid_t clock,
 				struct __kernel_timespec *res)
 {
-	const struct vdso_clock *vc = vd;
+	const struct vdso_clock *vc = vd->clock_data;
 	u32 msk;
 	u64 ns;
 
@@ -420,7 +420,7 @@ int __cvdso_clock_getres_common(const struct vdso_time_data *vd, clockid_t clock
 		/*
 		 * Preserves the behaviour of posix_get_hrtimer_res().
 		 */
-		ns = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
+		ns = READ_ONCE(vd->hrtimer_res);
 	} else if (msk & VDSO_COARSE) {
 		/*
 		 * Preserves the behaviour of posix_get_coarse_res().