timekeeping: Make timekeeping_inject_offset() reusable

Split out the inner workings for auxiliary clock support and feed the core time
keeper into it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/all/20250625183758.059934561@linutronix.de

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index b6ac7847bc0ae7024a0b0df37cafc879cd72fd93..2d294cfe185eba2138b5209df6a1132424b59c74 100644 (file)
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1433,32 +1433,32 @@ EXPORT_SYMBOL(do_settimeofday64);
 
 /**
  * __timekeeping_inject_offset - Adds or subtracts from the current time.
+ * @tkd:       Pointer to the timekeeper to modify
  * @ts:                Pointer to the timespec variable containing the offset
  *
  * Adds or subtracts an offset value from the current time.
  */
-static int __timekeeping_inject_offset(const struct timespec64 *ts)
+static int __timekeeping_inject_offset(struct tk_data *tkd, const struct timespec64 *ts)
 {
-       struct timekeeper *tks = &tk_core.shadow_timekeeper;
+       struct timekeeper *tks = &tkd->shadow_timekeeper;
        struct timespec64 tmp;
 
        if (ts->tv_nsec < 0 || ts->tv_nsec >= NSEC_PER_SEC)
                return -EINVAL;
 
-
        timekeeping_forward_now(tks);
 
        /* Make sure the proposed value is valid */
        tmp = timespec64_add(tk_xtime(tks), *ts);
        if (timespec64_compare(&tks->wall_to_monotonic, ts) > 0 ||
            !timespec64_valid_settod(&tmp)) {
-               timekeeping_restore_shadow(&tk_core);
+               timekeeping_restore_shadow(tkd);
                return -EINVAL;
        }
 
        tk_xtime_add(tks, ts);
        tk_set_wall_to_mono(tks, timespec64_sub(tks->wall_to_monotonic, *ts));
-       timekeeping_update_from_shadow(&tk_core, TK_UPDATE_ALL);
+       timekeeping_update_from_shadow(tkd, TK_UPDATE_ALL);
        return 0;
 }
 
@@ -1467,7 +1467,7 @@ static int timekeeping_inject_offset(const struct timespec64 *ts)
        int ret;
 
        scoped_guard (raw_spinlock_irqsave, &tk_core.lock)
-               ret = __timekeeping_inject_offset(ts);
+               ret = __timekeeping_inject_offset(&tk_core, ts);
 
        /* Signal hrtimers about time change */
        if (!ret)
@@ -2568,6 +2568,7 @@ EXPORT_SYMBOL_GPL(random_get_entropy_fallback);
  */
 int do_adjtimex(struct __kernel_timex *txc)
 {
+       struct tk_data *tkd = &tk_core;
        struct timespec64 delta, ts;
        struct audit_ntp_data ad;
        bool offset_set = false;
@@ -2585,16 +2586,19 @@ int do_adjtimex(struct __kernel_timex *txc)
        ktime_get_real_ts64(&ts);
        add_device_randomness(&ts, sizeof(ts));
 
-       scoped_guard (raw_spinlock_irqsave, &tk_core.lock) {
-               struct timekeeper *tks = &tk_core.shadow_timekeeper;
+       scoped_guard (raw_spinlock_irqsave, &tkd->lock) {
+               struct timekeeper *tks = &tkd->shadow_timekeeper;
                s32 orig_tai, tai;
 
+               if (!tks->clock_valid)
+                       return -ENODEV;
+
                if (txc->modes & ADJ_SETOFFSET) {
                        delta.tv_sec  = txc->time.tv_sec;
                        delta.tv_nsec = txc->time.tv_usec;
                        if (!(txc->modes & ADJ_NANO))
                                delta.tv_nsec *= 1000;
-                       ret = __timekeeping_inject_offset(&delta);
+                       ret = __timekeeping_inject_offset(tkd, &delta);
                        if (ret)
                                return ret;
 
@@ -2607,7 +2611,7 @@ int do_adjtimex(struct __kernel_timex *txc)
 
                if (tai != orig_tai) {
                        __timekeeping_set_tai_offset(tks, tai);
-                       timekeeping_update_from_shadow(&tk_core, TK_CLOCK_WAS_SET);
+                       timekeeping_update_from_shadow(tkd, TK_CLOCK_WAS_SET);
                        clock_set = true;
                } else {
                        tk_update_leap_state_all(&tk_core);
@@ -2615,7 +2619,7 @@ int do_adjtimex(struct __kernel_timex *txc)
 
                /* Update the multiplier immediately if frequency was set directly */
                if (txc->modes & (ADJ_FREQUENCY | ADJ_TICK))
-                       clock_set |= __timekeeping_advance(&tk_core, TK_ADV_FREQ);
+                       clock_set |= __timekeeping_advance(tkd, TK_ADV_FREQ);
        }
 
        if (txc->modes & ADJ_SETOFFSET)