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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 6ED18C47404 for ; Wed, 9 Oct 2019 19:25:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 409B320B7C for ; Wed, 9 Oct 2019 19:25:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731722AbfJITZ2 (ORCPT ); Wed, 9 Oct 2019 15:25:28 -0400 Received: from relay2-d.mail.gandi.net ([217.70.183.194]:53787 "EHLO relay2-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728804AbfJITZ2 (ORCPT ); Wed, 9 Oct 2019 15:25:28 -0400 X-Originating-IP: 86.202.229.42 Received: from localhost (lfbn-lyo-1-146-42.w86-202.abo.wanadoo.fr [86.202.229.42]) (Authenticated sender: alexandre.belloni@bootlin.com) by relay2-d.mail.gandi.net (Postfix) with ESMTPSA id 016ED40002; Wed, 9 Oct 2019 19:25:24 +0000 (UTC) Date: Wed, 9 Oct 2019 21:25:24 +0200 From: Alexandre Belloni To: Arnd Bergmann Cc: Al Viro , linux-kernel@vger.kernel.org, y2038@lists.linaro.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v6 10/43] compat_ioctl: move rtc handling into rtc-dev.c Message-ID: <20191009192524.GK4254@piout.net> References: <20191009190853.245077-1-arnd@arndb.de> <20191009191044.308087-10-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191009191044.308087-10-arnd@arndb.de> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, If you ever have to resend, the file is now named rtc/dev.c so you could adjust the subject. On 09/10/2019 21:10:10+0200, Arnd Bergmann wrote: > We no longer need the rtc compat handling to be in common code, now that > all drivers are either moved to the rtc-class framework, or (rarely) > exist in drivers/char for architectures without compat mode (m68k, > alpha and ia64, respectively). > > I checked the list of ioctl commands in drivers, and the ones that are > not already handled are all compatible, again with the one exception of > m68k driver, which implements RTC_PLL_GET and RTC_PLL_SET, but has no > compat mode. > > Since the ioctl commands are either compatible or differ in both structure > and command code between 32-bit and 64-bit, we can merge the compat > handler into the native one and just implement the two common compat > commands (RTC_IRQP_READ, RTC_IRQP_SET) there. The result is a slight > change in behavior, as a native 64-bit process will now also handle the > 32-bit commands (RTC_IRQP_SET32/RTC_IRQP_SET). > > The old conversion handler also deals with RTC_EPOCH_READ and > RTC_EPOCH_SET, which are not handled in rtc-dev.c but only in a single > device driver (rtc-vr41xx), so I'm adding the compat version in the same > place. I don't expect other drivers to need those commands in the future. > > Acked-by: Alexandre Belloni > Signed-off-by: Arnd Bergmann > --- > v2: merge compat handler into ioctl function to avoid the > compat_alloc_user_space() roundtrip, based on feedback > from Al Viro. > --- > drivers/rtc/dev.c | 13 +++++++++- > drivers/rtc/rtc-vr41xx.c | 10 ++++++++ > fs/compat_ioctl.c | 53 ---------------------------------------- > 3 files changed, 22 insertions(+), 54 deletions(-) > > diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c > index 84feb2565abd..1dc5063f78c9 100644 > --- a/drivers/rtc/dev.c > +++ b/drivers/rtc/dev.c > @@ -10,6 +10,7 @@ > > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > +#include > #include > #include > #include > @@ -357,10 +358,19 @@ static long rtc_dev_ioctl(struct file *file, > mutex_unlock(&rtc->ops_lock); > return rtc_update_irq_enable(rtc, 0); > > +#ifdef CONFIG_64BIT > +#define RTC_IRQP_SET32 _IOW('p', 0x0c, __u32) > +#define RTC_IRQP_READ32 _IOR('p', 0x0b, __u32) > + case RTC_IRQP_SET32: > + err = rtc_irq_set_freq(rtc, arg); > + break; > + case RTC_IRQP_READ32: > + err = put_user(rtc->irq_freq, (unsigned int __user *)uarg); > + break; > +#endif > case RTC_IRQP_SET: > err = rtc_irq_set_freq(rtc, arg); > break; > - > case RTC_IRQP_READ: > err = put_user(rtc->irq_freq, (unsigned long __user *)uarg); > break; > @@ -434,6 +444,7 @@ static const struct file_operations rtc_dev_fops = { > .read = rtc_dev_read, > .poll = rtc_dev_poll, > .unlocked_ioctl = rtc_dev_ioctl, > + .compat_ioctl = compat_ptr_ioctl, > .open = rtc_dev_open, > .release = rtc_dev_release, > .fasync = rtc_dev_fasync, > diff --git a/drivers/rtc/rtc-vr41xx.c b/drivers/rtc/rtc-vr41xx.c > index c75230562c0d..79f27de545af 100644 > --- a/drivers/rtc/rtc-vr41xx.c > +++ b/drivers/rtc/rtc-vr41xx.c > @@ -4,6 +4,7 @@ > * > * Copyright (C) 2003-2008 Yoichi Yuasa > */ > +#include > #include > #include > #include > @@ -66,6 +67,10 @@ static void __iomem *rtc2_base; > #define rtc2_read(offset) readw(rtc2_base + (offset)) > #define rtc2_write(offset, value) writew((value), rtc2_base + (offset)) > > +/* 32-bit compat for ioctls that nobody else uses */ > +#define RTC_EPOCH_READ32 _IOR('p', 0x0d, __u32) > +#define RTC_EPOCH_SET32 _IOW('p', 0x0e, __u32) > + > static unsigned long epoch = 1970; /* Jan 1 1970 00:00:00 */ > > static DEFINE_SPINLOCK(rtc_lock); > @@ -179,6 +184,11 @@ static int vr41xx_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long > switch (cmd) { > case RTC_EPOCH_READ: > return put_user(epoch, (unsigned long __user *)arg); > +#ifdef CONFIG_64BIT > + case RTC_EPOCH_READ32: > + return put_user(epoch, (unsigned int __user *)arg); > + case RTC_EPOCH_SET32: > +#endif > case RTC_EPOCH_SET: > /* Doesn't support before 1900 */ > if (arg < 1900) > diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c > index cec3ec0a1727..47da220f95b1 100644 > --- a/fs/compat_ioctl.c > +++ b/fs/compat_ioctl.c > @@ -32,7 +32,6 @@ > #include > #include > #include > -#include > #include > #include > #include > @@ -436,37 +435,6 @@ static int mt_ioctl_trans(struct file *file, > #define HCIUARTSETFLAGS _IOW('U', 203, int) > #define HCIUARTGETFLAGS _IOR('U', 204, int) > > -#define RTC_IRQP_READ32 _IOR('p', 0x0b, compat_ulong_t) > -#define RTC_IRQP_SET32 _IOW('p', 0x0c, compat_ulong_t) > -#define RTC_EPOCH_READ32 _IOR('p', 0x0d, compat_ulong_t) > -#define RTC_EPOCH_SET32 _IOW('p', 0x0e, compat_ulong_t) > - > -static int rtc_ioctl(struct file *file, > - unsigned cmd, void __user *argp) > -{ > - unsigned long __user *valp = compat_alloc_user_space(sizeof(*valp)); > - int ret; > - > - if (valp == NULL) > - return -EFAULT; > - switch (cmd) { > - case RTC_IRQP_READ32: > - case RTC_EPOCH_READ32: > - ret = do_ioctl(file, (cmd == RTC_IRQP_READ32) ? > - RTC_IRQP_READ : RTC_EPOCH_READ, > - (unsigned long)valp); > - if (ret) > - return ret; > - return convert_in_user(valp, (unsigned int __user *)argp); > - case RTC_IRQP_SET32: > - return do_ioctl(file, RTC_IRQP_SET, (unsigned long)argp); > - case RTC_EPOCH_SET32: > - return do_ioctl(file, RTC_EPOCH_SET, (unsigned long)argp); > - } > - > - return -ENOIOCTLCMD; > -} > - > /* > * simple reversible transform to make our table more evenly > * distributed after sorting. > @@ -503,21 +471,6 @@ COMPATIBLE_IOCTL(SCSI_IOCTL_GET_PCI) > /* Big V (don't complain on serial console) */ > IGNORE_IOCTL(VT_OPENQRY) > IGNORE_IOCTL(VT_GETMODE) > -/* Little p (/dev/rtc, /dev/envctrl, etc.) */ > -COMPATIBLE_IOCTL(RTC_AIE_ON) > -COMPATIBLE_IOCTL(RTC_AIE_OFF) > -COMPATIBLE_IOCTL(RTC_UIE_ON) > -COMPATIBLE_IOCTL(RTC_UIE_OFF) > -COMPATIBLE_IOCTL(RTC_PIE_ON) > -COMPATIBLE_IOCTL(RTC_PIE_OFF) > -COMPATIBLE_IOCTL(RTC_WIE_ON) > -COMPATIBLE_IOCTL(RTC_WIE_OFF) > -COMPATIBLE_IOCTL(RTC_ALM_SET) > -COMPATIBLE_IOCTL(RTC_ALM_READ) > -COMPATIBLE_IOCTL(RTC_RD_TIME) > -COMPATIBLE_IOCTL(RTC_SET_TIME) > -COMPATIBLE_IOCTL(RTC_WKALM_SET) > -COMPATIBLE_IOCTL(RTC_WKALM_RD) > /* > * These two are only for the sbus rtc driver, but > * hwclock tries them on every rtc device first when > @@ -897,12 +850,6 @@ static long do_ioctl_trans(unsigned int cmd, > case MTIOCPOS32: > return mt_ioctl_trans(file, cmd, argp); > #endif > - /* Not implemented in the native kernel */ > - case RTC_IRQP_READ32: > - case RTC_IRQP_SET32: > - case RTC_EPOCH_READ32: > - case RTC_EPOCH_SET32: > - return rtc_ioctl(file, cmd, argp); > } > > /* > -- > 2.20.0 > -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com