[PATCH v3 12/12] lib: vdso: do not expose gettimeofday, if no arch supported timer
From: Mark Salyzyn <hidden>
Date: 2017-10-27 22:28:10
Also in:
lkml
Subsystem:
generic vdso library, library code, the rest · Maintainers:
Andy Lutomirski, Thomas Gleixner, Vincenzo Frascino, Andrew Morton, Linus Torvalds
If ARCH_PROVIDES_TIMER is not defined, do not expose gettimeofday. libc will default directly to syscall. Also ifdef clock_gettime switch cases and stubs if not supported and other unused components. Signed-off-by: Mark Salyzyn <redacted> Cc: James Morse <james.morse@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <redacted> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dmitry Safonov <redacted> Cc: John Stultz <redacted> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Laura Abbott <redacted> Cc: Kees Cook <redacted> Cc: Ard Biesheuvel <redacted> Cc: Andy Gross <redacted> Cc: Kevin Brodsky <redacted> Cc: Andrew Pinski <redacted> Cc: linux-kernel at vger.kernel.org Cc: linux-arm-kernel at lists.infradead.org v3: - do not expose gettimeofday if arch does not support user space timer --- lib/vdso/vgettimeofday.c | 52 +++++++++++++++++++----------------------------- 1 file changed, 20 insertions(+), 32 deletions(-)
diff --git a/lib/vdso/vgettimeofday.c b/lib/vdso/vgettimeofday.c
index 0546ff12673d..22d0873778ed 100644
--- a/lib/vdso/vgettimeofday.c
+++ b/lib/vdso/vgettimeofday.c@@ -29,7 +29,9 @@ #include "compiler.h" #include "datapage.h" +#ifdef ARCH_PROVIDES_TIMER DEFINE_FALLBACK(gettimeofday, struct timeval *, tv, struct timezone *, tz) +#endif DEFINE_FALLBACK(clock_gettime, clockid_t, clock, struct timespec *, ts) DEFINE_FALLBACK(clock_getres, clockid_t, clock, struct timespec *, ts)
@@ -293,30 +295,6 @@ static __always_inline notrace int do_boottime(const struct vdso_data *vd, return 0; } -#else /* ARCH_PROVIDES_TIMER */ - -static notrace int do_realtime(const struct vdso_data *vd, struct timespec *ts) -{ - return -1; -} - -static notrace int do_monotonic(const struct vdso_data *vd, struct timespec *ts) -{ - return -1; -} - -static notrace int do_monotonic_raw(const struct vdso_data *vd, - struct timespec *ts) -{ - return -1; -} - -static notrace int do_boottime(const struct vdso_data *vd, - struct timespec *ts) -{ - return -1; -} - #endif /* ARCH_PROVIDES_TIMER */ notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts)
@@ -330,6 +308,7 @@ notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) case CLOCK_MONOTONIC_COARSE: do_monotonic_coarse(vd, ts); break; +#ifdef ARCH_PROVIDES_TIMER case CLOCK_REALTIME: if (do_realtime(vd, ts)) goto fallback;
@@ -346,6 +325,7 @@ notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) if (do_boottime(vd, ts)) goto fallback; break; +#endif default: goto fallback; }
@@ -355,6 +335,7 @@ notrace int __vdso_clock_gettime(clockid_t clock, struct timespec *ts) return clock_gettime_fallback(clock, ts); } +#ifdef ARCH_PROVIDES_TIMER notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) { const struct vdso_data *vd = __get_datapage();
@@ -376,21 +357,28 @@ notrace int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz) return 0; } +#endif int __vdso_clock_getres(clockid_t clock_id, struct timespec *res) { typeof(res->tv_nsec) nsec; - if (clock_id == CLOCK_REALTIME || - clock_id == CLOCK_BOOTTIME || - clock_id == CLOCK_MONOTONIC || - clock_id == CLOCK_MONOTONIC_RAW) - nsec = MONOTONIC_RES_NSEC; - else if (clock_id == CLOCK_REALTIME_COARSE || - clock_id == CLOCK_MONOTONIC_COARSE) + switch (clock_id) { + case CLOCK_REALTIME_COARSE: + case CLOCK_MONOTONIC_COARSE: nsec = LOW_RES_NSEC; - else + break; +#ifdef ARCH_PROVIDES_TIMER + case CLOCK_REALTIME: + case CLOCK_MONOTONIC: + case CLOCK_MONOTONIC_RAW: + case CLOCK_BOOTTIME: + nsec = MONOTONIC_RES_NSEC; + break; +#endif + default: return clock_getres_fallback(clock_id, res); + } if (likely(res != NULL)) { res->tv_sec = 0;
--
2.15.0.rc2.357.g7e34df9404-goog