From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.bootlin.com ([62.4.15.54]:39539 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726069AbeIMBGX (ORCPT ); Wed, 12 Sep 2018 21:06:23 -0400 Date: Wed, 12 Sep 2018 22:00:04 +0200 From: Alexandre Belloni To: Arnd Bergmann Cc: viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, Alessandro Zummo , linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 06/17] compat_ioctl: move rtc handling into rtc-dev.c Message-ID: <20180912200004.GM2760@piout.net> References: <20180912150142.157913-1-arnd@arndb.de> <20180912151134.436719-1-arnd@arndb.de> <20180912151134.436719-2-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180912151134.436719-2-arnd@arndb.de> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On 12/09/2018 17:08:53+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 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. > > Signed-off-by: Arnd Bergmann Acked-by: Alexandre Belloni > --- > v2: merge compat handler into ioctl function to avoid the > compat_alloc_user_space() roundtrip, based on feedback > from Al Viro. > --- > drivers/rtc/rtc-dev.c | 13 +++++++++- > drivers/rtc/rtc-vr41xx.c | 10 ++++++++ > fs/compat_ioctl.c | 54 ---------------------------------------- > 3 files changed, 22 insertions(+), 55 deletions(-) > > diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c > index 43d962a9c210..ccd5b1795e20 100644 > --- a/drivers/rtc/rtc-dev.c > +++ b/drivers/rtc/rtc-dev.c > @@ -13,6 +13,7 @@ > > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > +#include > #include > #include > #include > @@ -364,10 +365,19 @@ static long rtc_dev_ioctl(struct file *file, > mutex_unlock(&rtc->ops_lock); > return rtc_update_irq_enable(rtc, 0); > > +#ifdef CONFIG_COMPAT > +#define RTC_IRQP_SET32 _IOW('p', 0x0c, compat_ulong_t) > +#define RTC_IRQP_READ32 _IOR('p', 0x0b, compat_ulong_t) > + 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; > @@ -439,6 +449,7 @@ static const struct file_operations rtc_dev_fops = { > .read = rtc_dev_read, > .poll = rtc_dev_poll, > .unlocked_ioctl = rtc_dev_ioctl, > + .compat_ioctl = generic_compat_ioctl_ptrarg, > .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 70f013e692b0..1d90bde59d21 100644 > --- a/drivers/rtc/rtc-vr41xx.c > +++ b/drivers/rtc/rtc-vr41xx.c > @@ -17,6 +17,7 @@ > * along with this program; if not, write to the Free Software > * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA > */ > +#include > #include > #include > #include > @@ -79,6 +80,10 @@ 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, compat_ulong_t) > +#define RTC_EPOCH_SET32 _IOW('p', 0x0e, compat_ulong_t) > + > static unsigned long epoch = 1970; /* Jan 1 1970 00:00:00 */ > > static DEFINE_SPINLOCK(rtc_lock); > @@ -195,6 +200,11 @@ 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_COMPAT > + 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 2d7c7e149083..312b52b4e974 100644 > --- a/fs/compat_ioctl.c > +++ b/fs/compat_ioctl.c > @@ -46,7 +46,6 @@ > #include > #include > #include > -#include > #include > #include > #include > @@ -633,37 +632,6 @@ static int serial_struct_ioctl(struct file *file, > return err; > } > > -#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; > -} > - > /* on ia32 l_start is on a 32-bit boundary */ > #if defined(CONFIG_IA64) || defined(CONFIG_X86_64) > struct space_resv_32 { > @@ -816,21 +784,6 @@ 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 > @@ -1307,13 +1260,6 @@ static long do_ioctl_trans(unsigned int cmd, > case TIOCGSERIAL: > case TIOCSSERIAL: > return serial_struct_ioctl(file, cmd, argp); > - /* 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); > - > /* dvb */ > case VIDEO_GET_EVENT: > return do_video_get_event(file, cmd, argp); > -- > 2.18.0 > -- Alexandre Belloni, Bootlin Embedded Linux and Kernel engineering https://bootlin.com