To allow syscall fallbacks using the legacy 32bit syscall for 32bit VDSO
builds, move the fallback invocation out into the callers.
Split the common code out of __cvdso_clock_gettime/getres() and invoke the
syscall fallback in the 64bit and 32bit variants.
Preparatory work for using legacy syscalls in 32bit VDSO. No functional
change.
Fixes: 00b26474c2f1 ("lib/vdso: Provide generic VDSO implementation")
Signed-off-by: Thomas Gleixner <[email protected]>
---
lib/vdso/gettimeofday.c | 53 ++++++++++++++++++++++++++++++++----------------
1 file changed, 36 insertions(+), 17 deletions(-)
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -51,7 +51,7 @@ static int do_hres(const struct vdso_dat
ns = vdso_ts->nsec;
last = vd->cycle_last;
if (unlikely((s64)cycles < 0))
- return clock_gettime_fallback(clk, ts);
+ return -1;
ns += vdso_calc_delta(cycles, last, vd->mask, vd->mult);
ns >>= vd->shift;
@@ -82,14 +82,14 @@ static void do_coarse(const struct vdso_
}
static __maybe_unused int
-__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
+__cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts)
{
const struct vdso_data *vd = __arch_get_vdso_data();
u32 msk;
/* Check for negative values or invalid clocks */
if (unlikely((u32) clock >= MAX_CLOCKS))
- goto fallback;
+ return -1;
/*
* Convert the clockid to a bitmask and use it to check which
@@ -104,9 +104,17 @@ static __maybe_unused int
} else if (msk & VDSO_RAW) {
return do_hres(&vd[CS_RAW], clock, ts);
}
+ return -1;
+}
-fallback:
- return clock_gettime_fallback(clock, ts);
+static __maybe_unused int
+__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
+{
+ int ret = __cvdso_clock_gettime_common(clock, ts);
+
+ if (unlikely(ret))
+ return clock_gettime_fallback(clock, ts);
+ return 0;
}
static __maybe_unused int
@@ -115,9 +123,12 @@ static __maybe_unused int
struct __kernel_timespec ts;
int ret;
- ret = __cvdso_clock_gettime(clock, &ts);
+ ret = __cvdso_clock_gettime_common(clock, &ts);
- if (ret == 0) {
+ if (unlikely(ret))
+ ret = clock_gettime_fallback(clock, &ts);
+
+ if (likely(!ret)) {
res->tv_sec = ts.tv_sec;
res->tv_nsec = ts.tv_nsec;
}
@@ -163,17 +174,18 @@ static __maybe_unused time_t __cvdso_tim
#ifdef VDSO_HAS_CLOCK_GETRES
static __maybe_unused
-int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)
+int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res)
{
const struct vdso_data *vd = __arch_get_vdso_data();
- u64 ns;
+ u64 hrtimer_res;
u32 msk;
- u64 hrtimer_res = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
+ u64 ns;
/* Check for negative values or invalid clocks */
if (unlikely((u32) clock >= MAX_CLOCKS))
- goto fallback;
+ return -1;
+ hrtimer_res = READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res);
/*
* Convert the clockid to a bitmask and use it to check which
* clocks are handled in the VDSO directly.
@@ -195,16 +207,22 @@ int __cvdso_clock_getres(clockid_t clock
*/
ns = hrtimer_res;
} else {
- goto fallback;
+ return -1;
}
res->tv_sec = 0;
res->tv_nsec = ns;
return 0;
+}
+
+int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)
+{
+ int ret = __cvdso_clock_getres_common(clock, res);
-fallback:
- return clock_getres_fallback(clock, res);
+ if (unlikely(ret))
+ return clock_getres_fallback(clock, res);
+ return 0;
}
static __maybe_unused int
@@ -213,13 +231,14 @@ static __maybe_unused int
struct __kernel_timespec ts;
int ret;
- ret = __cvdso_clock_getres(clock, &ts);
+ ret = __cvdso_clock_getres_common(clock, &ts);
+ if (unlikely(ret))
+ ret = clock_getres_fallback(clock, &ts);
- if (ret == 0) {
+ if (likely(!ret)) {
res->tv_sec = ts.tv_sec;
res->tv_nsec = ts.tv_nsec;
}
-
return ret;
}
#endif /* VDSO_HAS_CLOCK_GETRES */
