[PATCH 0/3] y2038: remove unused interfaces

[PATCH 0/3] y2038: remove unused interfaces

[Arnd Bergmann]

Hi Andrew,

Can you add these to your patches for linux-5.6?

I have y2038 cleanups for sound, v4l, nfsd, scsi and xfs that are
merged in the respective subsystem trees, as well as another
series of individual patches queued up in my own y2038 tree.

With all that work merged, most of include/linux/time32.h
and some other related code can be removed from the kernel,
so it would be good to send these at the end of the coming
merge window, and to give them some more testing in linux-next
to make sure we don't gain any new users.

      Arnd

Arnd Bergmann (3):
  y2038: remove ktime to/from timespec/timeval conversion
  y2038: remove unused time32 interfaces
  y2038: hide timeval/timespec/itimerval/itimerspec types

 include/linux/compat.h                 |  29 -----
 include/linux/ktime.h                  |  37 ------
 include/linux/time32.h                 | 154 +------------------------
 include/linux/timekeeping32.h          |  32 -----
 include/linux/types.h                  |   5 -
 include/uapi/asm-generic/posix_types.h |   2 +
 include/uapi/linux/time.h              |  22 ++--
 kernel/compat.c                        |  64 ----------
 kernel/time/time.c                     |  43 -------
 9 files changed, 15 insertions(+), 373 deletions(-)

-- 

Cc: y2038@lists.linaro.org
Cc: linux-kernel@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
2.20.0

[PATCH 1/3] y2038: remove ktime to/from timespec/timeval conversion

[Arnd Bergmann]

A couple of helpers are now obsolete and can be removed, so drivers can
no longer start using them and instead use y2038-safe interfaces.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 include/linux/ktime.h | 37 -------------------------------------
 1 file changed, 37 deletions(-)

diff --git a/include/linux/ktime.h b/include/linux/ktime.h
index b2bb44f87f5a..d1fb05135665 100644
--- a/include/linux/ktime.h
+++ b/include/linux/ktime.h
@@ -66,33 +66,15 @@ static inline ktime_t ktime_set(const s64 secs, const unsigned long nsecs)
  */
 #define ktime_sub_ns(kt, nsval)		((kt) - (nsval))
 
-/* convert a timespec to ktime_t format: */
-static inline ktime_t timespec_to_ktime(struct timespec ts)
-{
-	return ktime_set(ts.tv_sec, ts.tv_nsec);
-}
-
 /* convert a timespec64 to ktime_t format: */
 static inline ktime_t timespec64_to_ktime(struct timespec64 ts)
 {
 	return ktime_set(ts.tv_sec, ts.tv_nsec);
 }
 
-/* convert a timeval to ktime_t format: */
-static inline ktime_t timeval_to_ktime(struct timeval tv)
-{
-	return ktime_set(tv.tv_sec, tv.tv_usec * NSEC_PER_USEC);
-}
-
-/* Map the ktime_t to timespec conversion to ns_to_timespec function */
-#define ktime_to_timespec(kt)		ns_to_timespec((kt))
-
 /* Map the ktime_t to timespec conversion to ns_to_timespec function */
 #define ktime_to_timespec64(kt)		ns_to_timespec64((kt))
 
-/* Map the ktime_t to timeval conversion to ns_to_timeval function */
-#define ktime_to_timeval(kt)		ns_to_timeval((kt))
-
 /* Convert ktime_t to nanoseconds */
 static inline s64 ktime_to_ns(const ktime_t kt)
 {
@@ -215,25 +197,6 @@ static inline ktime_t ktime_sub_ms(const ktime_t kt, const u64 msec)
 
 extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs);
 
-/**
- * ktime_to_timespec_cond - convert a ktime_t variable to timespec
- *			    format only if the variable contains data
- * @kt:		the ktime_t variable to convert
- * @ts:		the timespec variable to store the result in
- *
- * Return: %true if there was a successful conversion, %false if kt was 0.
- */
-static inline __must_check bool ktime_to_timespec_cond(const ktime_t kt,
-						       struct timespec *ts)
-{
-	if (kt) {
-		*ts = ktime_to_timespec(kt);
-		return true;
-	} else {
-		return false;
-	}
-}
-
 /**
  * ktime_to_timespec64_cond - convert a ktime_t variable to timespec64
  *			    format only if the variable contains data
-- 
2.20.0

[PATCH 2/3] y2038: remove unused time32 interfaces

[Arnd Bergmann]

No users remain, so kill these off before we grow new ones.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 include/linux/compat.h        |  29 -------
 include/linux/time32.h        | 154 +---------------------------------
 include/linux/timekeeping32.h |  32 -------
 include/linux/types.h         |   5 --
 kernel/compat.c               |  64 --------------
 kernel/time/time.c            |  43 ----------
 6 files changed, 1 insertion(+), 326 deletions(-)

diff --git a/include/linux/compat.h b/include/linux/compat.h
index 11083d84eb23..df2475be134a 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -248,15 +248,6 @@ typedef struct compat_siginfo {
 	} _sifields;
 } compat_siginfo_t;
 
-/*
- * These functions operate on 32- or 64-bit specs depending on
- * COMPAT_USE_64BIT_TIME, hence the void user pointer arguments.
- */
-extern int compat_get_timespec(struct timespec *, const void __user *);
-extern int compat_put_timespec(const struct timespec *, void __user *);
-extern int compat_get_timeval(struct timeval *, const void __user *);
-extern int compat_put_timeval(const struct timeval *, void __user *);
-
 struct compat_iovec {
 	compat_uptr_t	iov_base;
 	compat_size_t	iov_len;
@@ -416,26 +407,6 @@ int copy_siginfo_to_user32(struct compat_siginfo __user *to, const kernel_siginf
 int get_compat_sigevent(struct sigevent *event,
 		const struct compat_sigevent __user *u_event);
 
-static inline int old_timeval32_compare(struct old_timeval32 *lhs,
-					struct old_timeval32 *rhs)
-{
-	if (lhs->tv_sec < rhs->tv_sec)
-		return -1;
-	if (lhs->tv_sec > rhs->tv_sec)
-		return 1;
-	return lhs->tv_usec - rhs->tv_usec;
-}
-
-static inline int old_timespec32_compare(struct old_timespec32 *lhs,
-					struct old_timespec32 *rhs)
-{
-	if (lhs->tv_sec < rhs->tv_sec)
-		return -1;
-	if (lhs->tv_sec > rhs->tv_sec)
-		return 1;
-	return lhs->tv_nsec - rhs->tv_nsec;
-}
-
 extern int get_compat_sigset(sigset_t *set, const compat_sigset_t __user *compat);
 
 /*
diff --git a/include/linux/time32.h b/include/linux/time32.h
index cad4c3186002..cf9320cd2d0b 100644
--- a/include/linux/time32.h
+++ b/include/linux/time32.h
@@ -12,8 +12,6 @@
 #include <linux/time64.h>
 #include <linux/timex.h>
 
-#define TIME_T_MAX	(__kernel_old_time_t)((1UL << ((sizeof(__kernel_old_time_t) << 3) - 1)) - 1)
-
 typedef s32		old_time32_t;
 
 struct old_timespec32 {
@@ -73,162 +71,12 @@ struct __kernel_timex;
 int get_old_timex32(struct __kernel_timex *, const struct old_timex32 __user *);
 int put_old_timex32(struct old_timex32 __user *, const struct __kernel_timex *);
 
-#if __BITS_PER_LONG == 64
-
-/* timespec64 is defined as timespec here */
-static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
-{
-	return *(const struct timespec *)&ts64;
-}
-
-static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
-{
-	return *(const struct timespec64 *)&ts;
-}
-
-#else
-static inline struct timespec timespec64_to_timespec(const struct timespec64 ts64)
-{
-	struct timespec ret;
-
-	ret.tv_sec = (time_t)ts64.tv_sec;
-	ret.tv_nsec = ts64.tv_nsec;
-	return ret;
-}
-
-static inline struct timespec64 timespec_to_timespec64(const struct timespec ts)
-{
-	struct timespec64 ret;
-
-	ret.tv_sec = ts.tv_sec;
-	ret.tv_nsec = ts.tv_nsec;
-	return ret;
-}
-#endif
-
-static inline int timespec_equal(const struct timespec *a,
-				 const struct timespec *b)
-{
-	return (a->tv_sec == b->tv_sec) && (a->tv_nsec == b->tv_nsec);
-}
-
-/*
- * lhs < rhs:  return <0
- * lhs == rhs: return 0
- * lhs > rhs:  return >0
- */
-static inline int timespec_compare(const struct timespec *lhs, const struct timespec *rhs)
-{
-	if (lhs->tv_sec < rhs->tv_sec)
-		return -1;
-	if (lhs->tv_sec > rhs->tv_sec)
-		return 1;
-	return lhs->tv_nsec - rhs->tv_nsec;
-}
-
-/*
- * Returns true if the timespec is norm, false if denorm:
- */
-static inline bool timespec_valid(const struct timespec *ts)
-{
-	/* Dates before 1970 are bogus */
-	if (ts->tv_sec < 0)
-		return false;
-	/* Can't have more nanoseconds then a second */
-	if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
-		return false;
-	return true;
-}
-
-/**
- * timespec_to_ns - Convert timespec to nanoseconds
- * @ts:		pointer to the timespec variable to be converted
- *
- * Returns the scalar nanosecond representation of the timespec
- * parameter.
- */
-static inline s64 timespec_to_ns(const struct timespec *ts)
-{
-	return ((s64) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
-}
-
 /**
- * ns_to_timespec - Convert nanoseconds to timespec
- * @nsec:	the nanoseconds value to be converted
- *
- * Returns the timespec representation of the nsec parameter.
- */
-extern struct timespec ns_to_timespec(const s64 nsec);
-
-/**
- * timespec_add_ns - Adds nanoseconds to a timespec
- * @a:		pointer to timespec to be incremented
- * @ns:		unsigned nanoseconds value to be added
- *
- * This must always be inlined because its used from the x86-64 vdso,
- * which cannot call other kernel functions.
- */
-static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
-{
-	a->tv_sec += __iter_div_u64_rem(a->tv_nsec + ns, NSEC_PER_SEC, &ns);
-	a->tv_nsec = ns;
-}
-
-static inline unsigned long mktime(const unsigned int year,
-			const unsigned int mon, const unsigned int day,
-			const unsigned int hour, const unsigned int min,
-			const unsigned int sec)
-{
-	return mktime64(year, mon, day, hour, min, sec);
-}
-
-static inline bool timeval_valid(const struct timeval *tv)
-{
-	/* Dates before 1970 are bogus */
-	if (tv->tv_sec < 0)
-		return false;
-
-	/* Can't have more microseconds then a second */
-	if (tv->tv_usec < 0 || tv->tv_usec >= USEC_PER_SEC)
-		return false;
-
-	return true;
-}
-
-/**
- * timeval_to_ns - Convert timeval to nanoseconds
- * @ts:		pointer to the timeval variable to be converted
- *
- * Returns the scalar nanosecond representation of the timeval
- * parameter.
- */
-static inline s64 timeval_to_ns(const struct timeval *tv)
-{
-	return ((s64) tv->tv_sec * NSEC_PER_SEC) +
-		tv->tv_usec * NSEC_PER_USEC;
-}
-
-/**
- * ns_to_timeval - Convert nanoseconds to timeval
+ * ns_to_kernel_old_timeval - Convert nanoseconds to timeval
  * @nsec:	the nanoseconds value to be converted
  *
  * Returns the timeval representation of the nsec parameter.
  */
-extern struct timeval ns_to_timeval(const s64 nsec);
 extern struct __kernel_old_timeval ns_to_kernel_old_timeval(s64 nsec);
 
-/*
- * Old names for the 32-bit time_t interfaces, these will be removed
- * when everything uses the new names.
- */
-#define compat_time_t		old_time32_t
-#define compat_timeval		old_timeval32
-#define compat_timespec		old_timespec32
-#define compat_itimerspec	old_itimerspec32
-#define ns_to_compat_timeval	ns_to_old_timeval32
-#define get_compat_itimerspec64	get_old_itimerspec32
-#define put_compat_itimerspec64	put_old_itimerspec32
-#define compat_get_timespec64	get_old_timespec32
-#define compat_put_timespec64	put_old_timespec32
-
 #endif
diff --git a/include/linux/timekeeping32.h b/include/linux/timekeeping32.h
index cc59cc9e0e84..266017fc9ee9 100644
--- a/include/linux/timekeeping32.h
+++ b/include/linux/timekeeping32.h
@@ -11,36 +11,4 @@ static inline unsigned long get_seconds(void)
 	return ktime_get_real_seconds();
 }
 
-static inline void getnstimeofday(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	ktime_get_real_ts64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
-static inline void ktime_get_ts(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	ktime_get_ts64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
-static inline void getrawmonotonic(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	ktime_get_raw_ts64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
-static inline void getboottime(struct timespec *ts)
-{
-	struct timespec64 ts64;
-
-	getboottime64(&ts64);
-	*ts = timespec64_to_timespec(ts64);
-}
-
 #endif
diff --git a/include/linux/types.h b/include/linux/types.h
index eb870ad42919..d3021c879179 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -65,11 +65,6 @@ typedef __kernel_ssize_t	ssize_t;
 typedef __kernel_ptrdiff_t	ptrdiff_t;
 #endif
 
-#ifndef _TIME_T
-#define _TIME_T
-typedef __kernel_old_time_t	time_t;
-#endif
-
 #ifndef _CLOCK_T
 #define _CLOCK_T
 typedef __kernel_clock_t	clock_t;
diff --git a/kernel/compat.c b/kernel/compat.c
index 95005f849c68..843dd17e6078 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -26,70 +26,6 @@
 
 #include <linux/uaccess.h>
 
-static int __compat_get_timeval(struct timeval *tv, const struct old_timeval32 __user *ctv)
-{
-	return (!access_ok(ctv, sizeof(*ctv)) ||
-			__get_user(tv->tv_sec, &ctv->tv_sec) ||
-			__get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
-}
-
-static int __compat_put_timeval(const struct timeval *tv, struct old_timeval32 __user *ctv)
-{
-	return (!access_ok(ctv, sizeof(*ctv)) ||
-			__put_user(tv->tv_sec, &ctv->tv_sec) ||
-			__put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
-}
-
-static int __compat_get_timespec(struct timespec *ts, const struct old_timespec32 __user *cts)
-{
-	return (!access_ok(cts, sizeof(*cts)) ||
-			__get_user(ts->tv_sec, &cts->tv_sec) ||
-			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
-}
-
-static int __compat_put_timespec(const struct timespec *ts, struct old_timespec32 __user *cts)
-{
-	return (!access_ok(cts, sizeof(*cts)) ||
-			__put_user(ts->tv_sec, &cts->tv_sec) ||
-			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
-}
-
-int compat_get_timeval(struct timeval *tv, const void __user *utv)
-{
-	if (COMPAT_USE_64BIT_TIME)
-		return copy_from_user(tv, utv, sizeof(*tv)) ? -EFAULT : 0;
-	else
-		return __compat_get_timeval(tv, utv);
-}
-EXPORT_SYMBOL_GPL(compat_get_timeval);
-
-int compat_put_timeval(const struct timeval *tv, void __user *utv)
-{
-	if (COMPAT_USE_64BIT_TIME)
-		return copy_to_user(utv, tv, sizeof(*tv)) ? -EFAULT : 0;
-	else
-		return __compat_put_timeval(tv, utv);
-}
-EXPORT_SYMBOL_GPL(compat_put_timeval);
-
-int compat_get_timespec(struct timespec *ts, const void __user *uts)
-{
-	if (COMPAT_USE_64BIT_TIME)
-		return copy_from_user(ts, uts, sizeof(*ts)) ? -EFAULT : 0;
-	else
-		return __compat_get_timespec(ts, uts);
-}
-EXPORT_SYMBOL_GPL(compat_get_timespec);
-
-int compat_put_timespec(const struct timespec *ts, void __user *uts)
-{
-	if (COMPAT_USE_64BIT_TIME)
-		return copy_to_user(uts, ts, sizeof(*ts)) ? -EFAULT : 0;
-	else
-		return __compat_put_timespec(ts, uts);
-}
-EXPORT_SYMBOL_GPL(compat_put_timespec);
-
 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
 
 /*
diff --git a/kernel/time/time.c b/kernel/time/time.c
index cdd7386115ff..3985b2b32d08 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -449,49 +449,6 @@ time64_t mktime64(const unsigned int year0, const unsigned int mon0,
 }
 EXPORT_SYMBOL(mktime64);
 
-/**
- * ns_to_timespec - Convert nanoseconds to timespec
- * @nsec:       the nanoseconds value to be converted
- *
- * Returns the timespec representation of the nsec parameter.
- */
-struct timespec ns_to_timespec(const s64 nsec)
-{
-	struct timespec ts;
-	s32 rem;
-
-	if (!nsec)
-		return (struct timespec) {0, 0};
-
-	ts.tv_sec = div_s64_rem(nsec, NSEC_PER_SEC, &rem);
-	if (unlikely(rem < 0)) {
-		ts.tv_sec--;
-		rem += NSEC_PER_SEC;
-	}
-	ts.tv_nsec = rem;
-
-	return ts;
-}
-EXPORT_SYMBOL(ns_to_timespec);
-
-/**
- * ns_to_timeval - Convert nanoseconds to timeval
- * @nsec:       the nanoseconds value to be converted
- *
- * Returns the timeval representation of the nsec parameter.
- */
-struct timeval ns_to_timeval(const s64 nsec)
-{
-	struct timespec ts = ns_to_timespec(nsec);
-	struct timeval tv;
-
-	tv.tv_sec = ts.tv_sec;
-	tv.tv_usec = (suseconds_t) ts.tv_nsec / 1000;
-
-	return tv;
-}
-EXPORT_SYMBOL(ns_to_timeval);
-
 struct __kernel_old_timeval ns_to_kernel_old_timeval(const s64 nsec)
 {
 	struct timespec64 ts = ns_to_timespec64(nsec);
-- 
2.20.0

[PATCH 3/3] y2038: hide timeval/timespec/itimerval/itimerspec types

[Arnd Bergmann]

There are no in-kernel users remaining, but there may still
be users that include linux/time.h instead of sys/time.h
from user space, so leave the types available to user space
while hiding them from kernel space.

Only the __kernel_old_* versions of these types remain now.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 include/uapi/asm-generic/posix_types.h |  2 ++
 include/uapi/linux/time.h              | 22 ++++++++++++----------
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/include/uapi/asm-generic/posix_types.h b/include/uapi/asm-generic/posix_types.h
index 2f9c80595ba7..b5f7594eee7a 100644
--- a/include/uapi/asm-generic/posix_types.h
+++ b/include/uapi/asm-generic/posix_types.h
@@ -87,7 +87,9 @@ typedef struct {
 typedef __kernel_long_t	__kernel_off_t;
 typedef long long	__kernel_loff_t;
 typedef __kernel_long_t	__kernel_old_time_t;
+#ifndef __KERNEL__
 typedef __kernel_long_t	__kernel_time_t;
+#endif
 typedef long long __kernel_time64_t;
 typedef __kernel_long_t	__kernel_clock_t;
 typedef int		__kernel_timer_t;
diff --git a/include/uapi/linux/time.h b/include/uapi/linux/time.h
index a655aa28dc6e..4f4b6e48e01c 100644
--- a/include/uapi/linux/time.h
+++ b/include/uapi/linux/time.h
@@ -5,6 +5,7 @@
 #include <linux/types.h>
 #include <linux/time_types.h>
 
+#ifndef __KERNEL__
 #ifndef _STRUCT_TIMESPEC
 #define _STRUCT_TIMESPEC
 struct timespec {
@@ -18,6 +19,17 @@ struct timeval {
 	__kernel_suseconds_t	tv_usec;	/* microseconds */
 };
 
+struct itimerspec {
+	struct timespec it_interval;/* timer period */
+	struct timespec it_value;	/* timer expiration */
+};
+
+struct itimerval {
+	struct timeval it_interval;/* timer interval */
+	struct timeval it_value;	/* current value */
+};
+#endif
+
 struct timezone {
 	int	tz_minuteswest;	/* minutes west of Greenwich */
 	int	tz_dsttime;	/* type of dst correction */
@@ -31,16 +43,6 @@ struct timezone {
 #define	ITIMER_VIRTUAL		1
 #define	ITIMER_PROF		2
 
-struct itimerspec {
-	struct timespec it_interval;	/* timer period */
-	struct timespec it_value;	/* timer expiration */
-};
-
-struct itimerval {
-	struct timeval it_interval;	/* timer interval */
-	struct timeval it_value;	/* current value */
-};
-
 /*
  * The IDs of the various system clocks (for POSIX.1b interval timers):
  */
-- 
2.20.0

Re: [PATCH 1/3] y2038: remove ktime to/from timespec/timeval conversion

[Thomas Gleixner]

Arnd Bergmann <arnd@arndb.de> writes:

> A couple of helpers are now obsolete and can be removed, so drivers can
> no longer start using them and instead use y2038-safe interfaces.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Acked-by: Thomas Gleixner <tglx@linutronix.de>

Re: [PATCH 2/3] y2038: remove unused time32 interfaces

[Thomas Gleixner]

Arnd Bergmann <arnd@arndb.de> writes:

> No users remain, so kill these off before we grow new ones.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Acked-by: Thomas Gleixner <tglx@linutronix.de>

Re: [PATCH 3/3] y2038: hide timeval/timespec/itimerval/itimerspec types

[Thomas Gleixner]

Arnd Bergmann <arnd@arndb.de> writes:

> There are no in-kernel users remaining, but there may still
> be users that include linux/time.h instead of sys/time.h
> from user space, so leave the types available to user space
> while hiding them from kernel space.
>
> Only the __kernel_old_* versions of these types remain now.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Acked-by: Thomas Gleixner <tglx@linutronix.de>