From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9059C433FF for ; Sun, 28 Jul 2019 13:21:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A9EC52087C for ; Sun, 28 Jul 2019 13:21:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726281AbfG1NUy (ORCPT ); Sun, 28 Jul 2019 09:20:54 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:51645 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726032AbfG1NUr (ORCPT ); Sun, 28 Jul 2019 09:20:47 -0400 Received: from localhost ([127.0.0.1] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1hrj6S-0003px-Jo; Sun, 28 Jul 2019 15:20:44 +0200 Message-Id: <20190728131648.695579736@linutronix.de> User-Agent: quilt/0.65 Date: Sun, 28 Jul 2019 15:12:53 +0200 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Andy Lutomirski , Vincenzo Frascino , Sean Christopherson , Kees Cook , Paul Bolle , Will Deacon Subject: [patch 2/5] lib/vdso: Move fallback invocation to the callers References: <20190728131251.622415456@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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 */