Now that pvclock doesn't require access to the fixmap, all vdso
variants can use it.

The kernel side isn't wired up for 32-bit kernels yet, but this
covers 32-bit and x32 userspace on 64-bit kernels.

Signed-off-by: Andy Lutomirski <l...@kernel.org>
---
 arch/x86/entry/vdso/vclock_gettime.c | 91 ++++++++++++++++--------------------
 1 file changed, 40 insertions(+), 51 deletions(-)

diff --git a/arch/x86/entry/vdso/vclock_gettime.c 
b/arch/x86/entry/vdso/vclock_gettime.c
index 59a98c25bde7..8602f06c759f 100644
--- a/arch/x86/entry/vdso/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vclock_gettime.c
@@ -17,8 +17,10 @@
 #include <asm/vvar.h>
 #include <asm/unistd.h>
 #include <asm/msr.h>
+#include <asm/pvclock.h>
 #include <linux/math64.h>
 #include <linux/time.h>
+#include <linux/kernel.h>
 
 #define gtod (&VVAR(vsyscall_gtod_data))
 
@@ -43,10 +45,6 @@ extern u8 pvclock_page
 
 #ifndef BUILD_VDSO32
 
-#include <linux/kernel.h>
-#include <asm/vsyscall.h>
-#include <asm/pvclock.h>
-
 notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
 {
        long ret;
@@ -64,8 +62,42 @@ notrace static long vdso_fallback_gtod(struct timeval *tv, 
struct timezone *tz)
        return ret;
 }
 
-#ifdef CONFIG_PARAVIRT_CLOCK
 
+#else
+
+notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
+{
+       long ret;
+
+       asm(
+               "mov %%ebx, %%edx \n"
+               "mov %2, %%ebx \n"
+               "call __kernel_vsyscall \n"
+               "mov %%edx, %%ebx \n"
+               : "=a" (ret)
+               : "0" (__NR_clock_gettime), "g" (clock), "c" (ts)
+               : "memory", "edx");
+       return ret;
+}
+
+notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
+{
+       long ret;
+
+       asm(
+               "mov %%ebx, %%edx \n"
+               "mov %2, %%ebx \n"
+               "call __kernel_vsyscall \n"
+               "mov %%edx, %%ebx \n"
+               : "=a" (ret)
+               : "0" (__NR_gettimeofday), "g" (tv), "c" (tz)
+               : "memory", "edx");
+       return ret;
+}
+
+#endif
+
+#ifdef CONFIG_PARAVIRT_CLOCK
 static notrace const struct pvclock_vsyscall_time_info *get_pvti0(void)
 {
        return (const struct pvclock_vsyscall_time_info *)&pvclock_page;
@@ -109,9 +141,9 @@ static notrace cycle_t vread_pvclock(int *mode)
        do {
                version = pvti->version;
 
-               /* This is also a read barrier, so we'll read version first. */
-               tsc = rdtsc_ordered();
+               smp_rmb();
 
+               tsc = rdtsc_ordered();
                pvti_tsc_to_system_mul = pvti->tsc_to_system_mul;
                pvti_tsc_shift = pvti->tsc_shift;
                pvti_system_time = pvti->system_time;
@@ -126,7 +158,7 @@ static notrace cycle_t vread_pvclock(int *mode)
                pvclock_scale_delta(delta, pvti_tsc_to_system_mul,
                                    pvti_tsc_shift);
 
-       /* refer to tsc.c read_tsc() comment for rationale */
+       /* refer to vread_tsc() comment for rationale */
        last = gtod->cycle_last;
 
        if (likely(ret >= last))
@@ -136,49 +168,6 @@ static notrace cycle_t vread_pvclock(int *mode)
 }
 #endif
 
-#else
-
-notrace static long vdso_fallback_gettime(long clock, struct timespec *ts)
-{
-       long ret;
-
-       asm(
-               "mov %%ebx, %%edx \n"
-               "mov %2, %%ebx \n"
-               "call __kernel_vsyscall \n"
-               "mov %%edx, %%ebx \n"
-               : "=a" (ret)
-               : "0" (__NR_clock_gettime), "g" (clock), "c" (ts)
-               : "memory", "edx");
-       return ret;
-}
-
-notrace static long vdso_fallback_gtod(struct timeval *tv, struct timezone *tz)
-{
-       long ret;
-
-       asm(
-               "mov %%ebx, %%edx \n"
-               "mov %2, %%ebx \n"
-               "call __kernel_vsyscall \n"
-               "mov %%edx, %%ebx \n"
-               : "=a" (ret)
-               : "0" (__NR_gettimeofday), "g" (tv), "c" (tz)
-               : "memory", "edx");
-       return ret;
-}
-
-#ifdef CONFIG_PARAVIRT_CLOCK
-
-static notrace cycle_t vread_pvclock(int *mode)
-{
-       *mode = VCLOCK_NONE;
-       return 0;
-}
-#endif
-
-#endif
-
 notrace static cycle_t vread_tsc(void)
 {
        cycle_t ret = (cycle_t)rdtsc_ordered();
-- 
2.5.0

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