[PATCH v2 2/2] x86: convert x86_platform_ops to timespec64

[Arnd Bergmann <arnd@arndb.de>]

The x86 platform operations are fairly isolated, so we can
change them from using timespec to timespec64. I checked that
All the users and callers are safe, and there is only one
critical function that is broken beyond 2106:

pvclock_read_wallclock() uses a 32-bit number of seconds since
the epoch to communicate the boot time between host and guest
in a virtual environment. This will work until 2106, but we
should ideally find a replacement anyway. I've added a comment
about it there.

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
v2 changes:
- move comment block (Boris)
- remove unnecessary type cast (Boris)
- fix format string (0day bot)
- fix include order (0day bot)
---
 arch/x86/include/asm/intel_mid_vrtc.h        |  4 ++--
 arch/x86/include/asm/mc146818rtc.h           |  4 ++--
 arch/x86/include/asm/pvclock.h               |  2 +-
 arch/x86/include/asm/x86_init.h              |  7 +++----
 arch/x86/kernel/kvmclock.c                   |  4 ++--
 arch/x86/kernel/pvclock.c                    | 15 +++++++++++----
 arch/x86/kernel/rtc.c                        | 16 ++++++++--------
 arch/x86/platform/intel-mid/intel_mid_vrtc.c | 12 ++++++------
 arch/x86/xen/time.c                          | 10 +++++-----
 9 files changed, 40 insertions(+), 34 deletions(-)

diff --git a/arch/x86/include/asm/intel_mid_vrtc.h b/arch/x86/include/asm/intel_mid_vrtc.h
index 86ff4685c409..19202320f0be 100644
--- a/arch/x86/include/asm/intel_mid_vrtc.h
+++ b/arch/x86/include/asm/intel_mid_vrtc.h
@@ -3,7 +3,7 @@
 
 extern unsigned char vrtc_cmos_read(unsigned char reg);
 extern void vrtc_cmos_write(unsigned char val, unsigned char reg);
-extern void vrtc_get_time(struct timespec *now);
-extern int vrtc_set_mmss(const struct timespec *now);
+extern void vrtc_get_time(struct timespec64 *now);
+extern int vrtc_set_mmss(const struct timespec64 *now);
 
 #endif
diff --git a/arch/x86/include/asm/mc146818rtc.h b/arch/x86/include/asm/mc146818rtc.h
index 24acd9ba7837..1b574e5eb3b2 100644
--- a/arch/x86/include/asm/mc146818rtc.h
+++ b/arch/x86/include/asm/mc146818rtc.h
@@ -94,8 +94,8 @@ static inline unsigned char current_lock_cmos_reg(void)
 unsigned char rtc_cmos_read(unsigned char addr);
 void rtc_cmos_write(unsigned char val, unsigned char addr);
 
-extern int mach_set_rtc_mmss(const struct timespec *now);
-extern void mach_get_cmos_time(struct timespec *now);
+extern int mach_set_rtc_mmss(const struct timespec64 *now);
+extern void mach_get_cmos_time(struct timespec64 *now);
 
 #define RTC_IRQ 8
 
diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h
index 448cfe1b48cf..fc3138fd3aff 100644
--- a/arch/x86/include/asm/pvclock.h
+++ b/arch/x86/include/asm/pvclock.h
@@ -20,7 +20,7 @@ void pvclock_set_flags(u8 flags);
 unsigned long pvclock_tsc_khz(struct pvclock_vcpu_time_info *src);
 void pvclock_read_wallclock(struct pvclock_wall_clock *wall,
 			    struct pvclock_vcpu_time_info *vcpu,
-			    struct timespec *ts);
+			    struct timespec64 *ts);
 void pvclock_resume(void);
 
 void pvclock_touch_watchdogs(void);
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index f45acdf45957..847bdefa7807 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -1,6 +1,7 @@
 #ifndef _ASM_X86_PLATFORM_H
 #define _ASM_X86_PLATFORM_H
 
+#include <linux/time64.h>
 #include <asm/bootparam.h>
 
 struct mpc_bus;
@@ -141,8 +142,6 @@ struct x86_cpuinit_ops {
 	void (*fixup_cpu_id)(struct cpuinfo_x86 *c, int node);
 };
 
-struct timespec;
-
 /**
  * struct x86_legacy_devices - legacy x86 devices
  *
@@ -223,8 +222,8 @@ struct x86_legacy_features {
 struct x86_platform_ops {
 	unsigned long (*calibrate_cpu)(void);
 	unsigned long (*calibrate_tsc)(void);
-	void (*get_wallclock)(struct timespec *ts);
-	int (*set_wallclock)(const struct timespec *ts);
+	void (*get_wallclock)(struct timespec64 *ts);
+	int (*set_wallclock)(const struct timespec64 *ts);
 	void (*iommu_shutdown)(void);
 	bool (*is_untracked_pat_range)(u64 start, u64 end);
 	void (*nmi_init)(void);
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index d88967659098..01c76e8cd4be 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -58,7 +58,7 @@ EXPORT_SYMBOL_GPL(pvclock_pvti_cpu0_va);
  * have elapsed since the hypervisor wrote the data. So we try to account for
  * that with system time
  */
-static void kvm_get_wallclock(struct timespec *now)
+static void kvm_get_wallclock(struct timespec64 *now)
 {
 	struct pvclock_vcpu_time_info *vcpu_time;
 	int low, high;
@@ -77,7 +77,7 @@ static void kvm_get_wallclock(struct timespec *now)
 	put_cpu();
 }
 
-static int kvm_set_wallclock(const struct timespec *now)
+static int kvm_set_wallclock(const struct timespec64 *now)
 {
 	return -1;
 }
diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c
index 5c3f6d6a5078..013bef851664 100644
--- a/arch/x86/kernel/pvclock.c
+++ b/arch/x86/kernel/pvclock.c
@@ -121,26 +121,33 @@ u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src)
 
 void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock,
 			    struct pvclock_vcpu_time_info *vcpu_time,
-			    struct timespec *ts)
+			    struct timespec64 *ts)
 {
 	u32 version;
 	u64 delta;
-	struct timespec now;
+	struct timespec64 now;
 
 	/* get wallclock at system boot */
 	do {
 		version = wall_clock->version;
 		rmb();		/* fetch version before time */
+		/*
+		 * Note: wall_clock->sec is a u32 value, so it can
+		 * only store dates between 1970 and 2106. To allow
+		 * times beyond that, we need to create a new hypercall
+		 * interface with an extended pvclock_wall_clock structure
+		 * like ARM has.
+		 */
 		now.tv_sec  = wall_clock->sec;
 		now.tv_nsec = wall_clock->nsec;
 		rmb();		/* fetch time before checking version */
 	} while ((wall_clock->version & 1) || (version != wall_clock->version));
 
 	delta = pvclock_clocksource_read(vcpu_time);	/* time since system boot */
-	delta += now.tv_sec * (u64)NSEC_PER_SEC + now.tv_nsec;
+	delta += now.tv_sec * NSEC_PER_SEC + now.tv_nsec;
 
 	now.tv_nsec = do_div(delta, NSEC_PER_SEC);
 	now.tv_sec = delta;
 
-	set_normalized_timespec(ts, now.tv_sec, now.tv_nsec);
+	set_normalized_timespec64(ts, now.tv_sec, now.tv_nsec);
 }
diff --git a/arch/x86/kernel/rtc.c b/arch/x86/kernel/rtc.c
index 5b21cb7d84d6..f5a687c38c6d 100644
--- a/arch/x86/kernel/rtc.c
+++ b/arch/x86/kernel/rtc.c
@@ -38,13 +38,13 @@ EXPORT_SYMBOL(rtc_lock);
  * jump to the next second precisely 500 ms later. Check the Motorola
  * MC146818A or Dallas DS12887 data sheet for details.
  */
-int mach_set_rtc_mmss(const struct timespec *now)
+int mach_set_rtc_mmss(const struct timespec64 *now)
 {
-	unsigned long nowtime = now->tv_sec;
+	time64_t nowtime = now->tv_sec;
 	struct rtc_time tm;
 	int retval = 0;
 
-	rtc_time_to_tm(nowtime, &tm);
+	rtc_time64_to_tm(nowtime, &tm);
 	if (!rtc_valid_tm(&tm)) {
 		retval = mc146818_set_time(&tm);
 		if (retval)
@@ -52,14 +52,14 @@ int mach_set_rtc_mmss(const struct timespec *now)
 			       __func__, retval);
 	} else {
 		printk(KERN_ERR
-		       "%s: Invalid RTC value: write of %lx to RTC failed\n",
+		       "%s: Invalid RTC value: write of %llx to RTC failed\n",
 			__func__, nowtime);
 		retval = -EINVAL;
 	}
 	return retval;
 }
 
-void mach_get_cmos_time(struct timespec *now)
+void mach_get_cmos_time(struct timespec64 *now)
 {
 	unsigned int status, year, mon, day, hour, min, sec, century = 0;
 	unsigned long flags;
@@ -117,7 +117,7 @@ void mach_get_cmos_time(struct timespec *now)
 	} else
 		year += CMOS_YEARS_OFFS;
 
-	now->tv_sec = mktime(year, mon, day, hour, min, sec);
+	now->tv_sec = mktime64(year, mon, day, hour, min, sec);
 	now->tv_nsec = 0;
 }
 
@@ -144,13 +144,13 @@ void rtc_cmos_write(unsigned char val, unsigned char addr)
 }
 EXPORT_SYMBOL(rtc_cmos_write);
 
-int update_persistent_clock(struct timespec now)
+int update_persistent_clock64(struct timespec64 now)
 {
 	return x86_platform.set_wallclock(&now);
 }
 
 /* not static: needed by APM */
-void read_persistent_clock(struct timespec *ts)
+void read_persistent_clock64(struct timespec64 *ts)
 {
 	x86_platform.get_wallclock(ts);
 }
diff --git a/arch/x86/platform/intel-mid/intel_mid_vrtc.c b/arch/x86/platform/intel-mid/intel_mid_vrtc.c
index 58024862a7eb..a52914aa3b6c 100644
--- a/arch/x86/platform/intel-mid/intel_mid_vrtc.c
+++ b/arch/x86/platform/intel-mid/intel_mid_vrtc.c
@@ -57,7 +57,7 @@ void vrtc_cmos_write(unsigned char val, unsigned char reg)
 }
 EXPORT_SYMBOL_GPL(vrtc_cmos_write);
 
-void vrtc_get_time(struct timespec *now)
+void vrtc_get_time(struct timespec64 *now)
 {
 	u8 sec, min, hour, mday, mon;
 	unsigned long flags;
@@ -83,18 +83,18 @@ void vrtc_get_time(struct timespec *now)
 	pr_info("vRTC: sec: %d min: %d hour: %d day: %d "
 		"mon: %d year: %d\n", sec, min, hour, mday, mon, year);
 
-	now->tv_sec = mktime(year, mon, mday, hour, min, sec);
+	now->tv_sec = mktime64(year, mon, mday, hour, min, sec);
 	now->tv_nsec = 0;
 }
 
-int vrtc_set_mmss(const struct timespec *now)
+int vrtc_set_mmss(const struct timespec64 *now)
 {
 	unsigned long flags;
 	struct rtc_time tm;
 	int year;
 	int retval = 0;
 
-	rtc_time_to_tm(now->tv_sec, &tm);
+	rtc_time64_to_tm(now->tv_sec, &tm);
 	if (!rtc_valid_tm(&tm) && tm.tm_year >= 72) {
 		/*
 		 * tm.year is the number of years since 1900, and the
@@ -110,8 +110,8 @@ int vrtc_set_mmss(const struct timespec *now)
 		vrtc_cmos_write(tm.tm_sec, RTC_SECONDS);
 		spin_unlock_irqrestore(&rtc_lock, flags);
 	} else {
-		pr_err("%s: Invalid vRTC value: write of %lx to vRTC failed\n",
-			__func__, now->tv_sec);
+		pr_err("%s: Invalid vRTC value: write of %llx to vRTC failed\n",
+			__func__, (s64)now->tv_sec);
 		retval = -EINVAL;
 	}
 	return retval;
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 1ecb05db3632..b1eed21a7b46 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -56,7 +56,7 @@ static u64 xen_clocksource_get_cycles(struct clocksource *cs)
 	return xen_clocksource_read();
 }
 
-static void xen_read_wallclock(struct timespec *ts)
+static void xen_read_wallclock(struct timespec64 *ts)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	struct pvclock_wall_clock *wall_clock = &(s->wc);
@@ -67,12 +67,12 @@ static void xen_read_wallclock(struct timespec *ts)
 	put_cpu_var(xen_vcpu);
 }
 
-static void xen_get_wallclock(struct timespec *now)
+static void xen_get_wallclock(struct timespec64 *now)
 {
 	xen_read_wallclock(now);
 }
 
-static int xen_set_wallclock(const struct timespec *now)
+static int xen_set_wallclock(const struct timespec64 *now)
 {
 	return -1;
 }
@@ -373,7 +373,7 @@ static const struct pv_time_ops xen_time_ops __initconst = {
 static void __init xen_time_init(void)
 {
 	int cpu = smp_processor_id();
-	struct timespec tp;
+	struct timespec64 tp;
 
 	/* As Dom0 is never moved, no penalty on using TSC there */
 	if (xen_initial_domain())
@@ -391,7 +391,7 @@ static void __init xen_time_init(void)
 
 	/* Set initial system time with full resolution */
 	xen_read_wallclock(&tp);
-	do_settimeofday(&tp);
+	do_settimeofday64(&tp);
 
 	setup_force_cpu_cap(X86_FEATURE_TSC);
 
-- 
2.9.0