From: Stefani Seibold <stef...@seibold.net>

This patch add the VDSO time support for the IA32 Emulation Layer.

Due the nature of the kernel headers and the LP64 compiler where the
size of a long and a pointer differs against a 32 bit compiler, there
is a lot of type hacking necessary.

Signed-off-by: Stefani Seibold <stef...@seibold.net>
---
 arch/x86/vdso/vclock_gettime.c        | 109 +++++++++++++++++++++++++++-------
 arch/x86/vdso/vdso32/vclock_gettime.c |   7 +++
 2 files changed, 95 insertions(+), 21 deletions(-)

diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
index 42f641c..cd33f05 100644
--- a/arch/x86/vdso/vclock_gettime.c
+++ b/arch/x86/vdso/vclock_gettime.c
@@ -31,12 +31,24 @@
 
 #define gtod (&VVAR(vsyscall_gtod_data))
 
+struct api_timeval {
+       long    tv_sec;         /* seconds */
+       long    tv_usec;        /* microseconds */
+};
+
+struct api_timespec {
+       long    tv_sec;         /* seconds */
+       long    tv_nsec;        /* microseconds */
+};
+
+typedef long api_time_t;
+
 static notrace cycle_t vread_hpet(void)
 {
        return readl((const void __iomem *)fix_to_virt(VSYSCALL_HPET) + 
HPET_COUNTER);
 }
 
-notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
+notrace static long vdso_fallback_gettime(long clock, struct api_timespec *ts)
 {
        long ret;
        asm("syscall" : "=a" (ret) :
@@ -44,7 +56,8 @@ notrace static long vdso_fallback_gettime(long clock, struct 
timespec *ts)
        return ret;
 }
 
-notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
+notrace static long vdso_fallback_gtod(struct api_timeval *tv,
+               struct timezone *tz)
 {
        long ret;
 
@@ -54,14 +67,62 @@ notrace static long vdso_fallback_gtod(struct timeval *tv, 
struct timezone *tz)
 }
 #else
 
+#ifdef CONFIG_IA32_EMULATION
+typedef s64    arch_time_t;
+
+struct arch_timespec {
+       s64     tv_sec;
+       s64     tv_nsec;
+};
+
+#define ALIGN8 __attribute__ ((aligned (8)))
+
+struct arch_vsyscall_gtod_data {
+       seqcount_t      seq ALIGN8;
+
+       struct { /* extract of a clocksource struct */
+               int vclock_mode ALIGN8;
+               cycle_t cycle_last ALIGN8;
+               cycle_t mask ALIGN8;
+               u32     mult;
+               u32     shift;
+       } clock;
+
+       /* open coded 'struct timespec' */
+       arch_time_t     wall_time_sec;
+       u64             wall_time_snsec;
+       u64             monotonic_time_snsec;
+       arch_time_t     monotonic_time_sec;
+
+       struct timezone sys_tz;
+       struct arch_timespec wall_time_coarse;
+       struct arch_timespec monotonic_time_coarse;
+};
+
+struct arch_vsyscall_gtod_data vvar_vsyscall_gtod_data
+       __attribute__((visibility("hidden")));
+#else
 struct vsyscall_gtod_data vvar_vsyscall_gtod_data
        __attribute__((visibility("hidden")));
+#endif
 
 u8 hpet_page
        __attribute__((visibility("hidden")));
 
 #define gtod (&vvar_vsyscall_gtod_data)
 
+struct api_timeval {
+       s32     tv_sec;         /* seconds */
+       s32     tv_usec;        /* microseconds */
+};
+
+struct api_timespec {
+       s32     tv_sec;         /* seconds */
+       s32     tv_nsec;        /* microseconds */
+};
+
+typedef s32 api_time_t;
+
 #ifdef CONFIG_HPET_TIMER
 static notrace cycle_t vread_hpet(void)
 {
@@ -69,7 +130,7 @@ static notrace cycle_t vread_hpet(void)
 }
 #endif
 
-notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
+notrace static long vdso_fallback_gettime(long clock, struct api_timespec *ts)
 {
        long ret;
 
@@ -79,12 +140,12 @@ notrace static long vdso_fallback_gettime(long clock, 
struct timespec *ts)
                "call VDSO32_vsyscall \n"
                "pop %%ebx \n"
                : "=a" (ret)
-               : "0" (__NR_clock_gettime), "d" (clock), "c" (ts)
+               : "0" (__NR_ia32_clock_gettime), "d" (clock), "c" (ts)
                : "memory");
        return ret;
 }
 
-notrace static long vdso_fallback_gtod(struct timeval *tv,
+notrace static long vdso_fallback_gtod(struct api_timeval *tv,
                struct timezone *tz)
 {
        long ret;
@@ -95,7 +156,7 @@ notrace static long vdso_fallback_gtod(struct timeval *tv,
                "call VDSO32_vsyscall \n"
                "pop %%ebx \n"
                : "=a" (ret)
-               : "0" (__NR_gettimeofday), "d" (tv), "c" (tz)
+               : "0" (__NR_ia32_gettimeofday), "d" (tv), "c" (tz)
                : "memory");
        return ret;
 }
@@ -284,42 +345,48 @@ notrace static void do_monotonic_coarse(struct timespec 
*ts)
        } while (unlikely(read_seqcount_retry(&gtod->seq, seq)));
 }
 
-notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
+notrace int __vdso_clock_gettime(clockid_t clock, struct api_timespec *ts)
 {
+       struct timespec tmp;
+
        switch (clock) {
        case CLOCK_REALTIME:
-               if (do_realtime(ts) == VCLOCK_NONE)
+               if (do_realtime(&tmp) == VCLOCK_NONE)
                        goto fallback;
                break;
        case CLOCK_MONOTONIC:
-               if (do_monotonic(ts) == VCLOCK_NONE)
+               if (do_monotonic(&tmp) == VCLOCK_NONE)
                        goto fallback;
                break;
        case CLOCK_REALTIME_COARSE:
-               do_realtime_coarse(ts);
+               do_realtime_coarse(&tmp);
                break;
        case CLOCK_MONOTONIC_COARSE:
-               do_monotonic_coarse(ts);
+               do_monotonic_coarse(&tmp);
                break;
        default:
                goto fallback;
        }
 
+       ts->tv_sec = tmp.tv_sec;
+       ts->tv_nsec = tmp.tv_nsec;
+
        return 0;
 fallback:
        return vdso_fallback_gettime(clock, ts);
 }
-int clock_gettime(clockid_t, struct timespec *)
+int clock_gettime(clockid_t, struct api_timespec *)
        __attribute__((weak, alias("__vdso_clock_gettime")));
 
-notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
+notrace int __vdso_gettimeofday(struct api_timeval *tv, struct timezone *tz)
 {
+       struct timespec tmp;
+
        if (likely(tv != NULL)) {
-               BUILD_BUG_ON(offsetof(struct timeval, tv_usec) !=
-                            offsetof(struct timespec, tv_nsec) ||
-                            sizeof(*tv) != sizeof(struct timespec));
-               if (do_realtime((struct timespec *)tv) == VCLOCK_NONE)
+               if (do_realtime(&tmp) == VCLOCK_NONE)
                        return vdso_fallback_gtod(tv, tz);
+               tv->tv_sec = tmp.tv_sec;
+               tv->tv_usec = tmp.tv_nsec;
                tv->tv_usec /= 1000;
        }
        if (unlikely(tz != NULL)) {
@@ -330,21 +397,21 @@ notrace int __vdso_gettimeofday(struct timeval *tv, 
struct timezone *tz)
 
        return 0;
 }
-int gettimeofday(struct timeval *, struct timezone *)
+int gettimeofday(struct api_timeval *, struct timezone *)
        __attribute__((weak, alias("__vdso_gettimeofday")));
 
 /*
  * This will break when the xtime seconds get inaccurate, but that is
  * unlikely
  */
-notrace time_t __vdso_time(time_t *t)
+notrace api_time_t __vdso_time(api_time_t *t)
 {
        /* This is atomic on x86 so we don't need any locks. */
-       time_t result = ACCESS_ONCE(gtod->wall_time_sec);
+       api_time_t result = ACCESS_ONCE(gtod->wall_time_sec);
 
        if (t)
                *t = result;
        return result;
 }
-int time(time_t *t)
+int time(api_time_t *t)
        __attribute__((weak, alias("__vdso_time")));
diff --git a/arch/x86/vdso/vdso32/vclock_gettime.c 
b/arch/x86/vdso/vdso32/vclock_gettime.c
index fab4ec6..b6df952 100644
--- a/arch/x86/vdso/vdso32/vclock_gettime.c
+++ b/arch/x86/vdso/vdso32/vclock_gettime.c
@@ -2,6 +2,8 @@
 
 #ifdef CONFIG_X86_64
 
+#include <generated/asm/unistd_32_ia32.h>
+
 #define _ASM_X86_PAGE_H
 
 #define __pa(x)                0
@@ -10,6 +12,11 @@
 #undef CONFIG_ILLEGAL_POINTER_VALUE
 #define CONFIG_ILLEGAL_POINTER_VALUE   0
 
+#else
+
+#define __NR_ia32_clock_gettime        __NR_clock_gettime
+#define __NR_ia32_gettimeofday __NR_gettimeofday
+
 #endif
 
 #include "../vclock_gettime.c"
-- 
1.8.5.3

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