Commit 076ff658 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

compat_ioctl: move rtc handling into drivers/rtc/dev.c 



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.

Unlike earlier versions of this patch, I'm now adding a separate
compat_ioctl handler that takes care of RTC_IRQP_READ32/RTC_IRQP_SET32
and treats all other commands as compatible, leaving the native
behavior unchanged.

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: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: default avatarBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
---
v4: handle RTC_EPOCH_SET32 in rtc_dev_compat_ioctl
v3: handle RTC_IRQP_READ32/RTC_IRQP_SET32 in rtc_dev_compat_ioctl
v2: merge compat handler into ioctl function to avoid the
    compat_alloc_user_space() roundtrip, based on feedback
    from Al Viro.
parent 18bd6caa

drivers/rtc/dev.c

+32 −1
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt



#include <linux/compat.h>

#include <linux/module.h>

#include <linux/rtc.h>

#include <linux/sched/signal.h>
@@ -360,7 +361,6 @@ static long rtc_dev_ioctl(struct file *file, 
	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;
@@ -399,6 +399,34 @@ done: 
	return err;

}



#ifdef CONFIG_COMPAT

#define RTC_IRQP_SET32		_IOW('p', 0x0c, __u32)

#define RTC_IRQP_READ32		_IOR('p', 0x0b, __u32)

#define RTC_EPOCH_SET32		_IOW('p', 0x0e, __u32)



static long rtc_dev_compat_ioctl(struct file *file,

				 unsigned int cmd, unsigned long arg)

{

	struct rtc_device *rtc = file->private_data;

	void __user *uarg = compat_ptr(arg);



	switch (cmd) {

	case RTC_IRQP_READ32:

		return put_user(rtc->irq_freq, (__u32 __user *)uarg);



	case RTC_IRQP_SET32:

		/* arg is a plain integer, not pointer */

		return rtc_dev_ioctl(file, RTC_IRQP_SET, arg);



	case RTC_EPOCH_SET32:

		/* arg is a plain integer, not pointer */

		return rtc_dev_ioctl(file, RTC_EPOCH_SET, arg);

	}



	return rtc_dev_ioctl(file, cmd, (unsigned long)uarg);

}

#endif



static int rtc_dev_fasync(int fd, struct file *file, int on)

{

	struct rtc_device *rtc = file->private_data;
@@ -434,6 +462,9 @@ static const struct file_operations rtc_dev_fops = { 
	.read		= rtc_dev_read,

	.poll		= rtc_dev_poll,

	.unlocked_ioctl	= rtc_dev_ioctl,

#ifdef CONFIG_COMPAT

	.compat_ioctl	= rtc_dev_compat_ioctl,

#endif

	.open		= rtc_dev_open,

	.release	= rtc_dev_release,

	.fasync		= rtc_dev_fasync,

drivers/rtc/rtc-vr41xx.c

+8 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
 *

 *  Copyright (C) 2003-2008  Yoichi Yuasa <yuasa@linux-mips.org>

 */

#include <linux/compat.h>

#include <linux/err.h>

#include <linux/fs.h>

#include <linux/init.h>
@@ -66,6 +67,9 @@ 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)



static unsigned long epoch = 1970;	/* Jan 1 1970 00:00:00 */



static DEFINE_SPINLOCK(rtc_lock);
@@ -179,6 +183,10 @@ 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);

#endif

	case RTC_EPOCH_SET:

		/* Doesn't support before 1900 */

		if (arg < 1900)

fs/compat_ioctl.c

+0 −53
Original line number Diff line number Diff line
@@ -32,7 +32,6 @@ 
#include <linux/vt_kern.h>

#include <linux/raw.h>

#include <linux/blkdev.h>

#include <linux/rtc.h>

#include <linux/pci.h>

#include <linux/serial.h>

#include <linux/ctype.h>
@@ -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);

	}



	/*

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