diff mbox series

[v2,06/17] compat_ioctl: move rtc handling into rtc-dev.c

Message ID 20180912151134.436719-2-arnd@arndb.de
State New
Headers show
Series [v2,01/17] compat_ioctl: add generic_compat_ioctl_ptrarg() | expand

Commit Message

Arnd Bergmann Sept. 12, 2018, 3:08 p.m. UTC 
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 <arnd@arndb.de>

---
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(-)

-- 
2.18.0

Comments

Alexandre Belloni Sept. 12, 2018, 8 p.m. UTC | #1 
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 <arnd@arndb.de>

Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>


> ---

> 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 <linux/compat.h>

>  #include <linux/module.h>

>  #include <linux/rtc.h>

>  #include <linux/sched/signal.h>

> @@ -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 <linux/compat.h>

>  #include <linux/err.h>

>  #include <linux/fs.h>

>  #include <linux/init.h>

> @@ -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 <linux/raw.h>

>  #include <linux/blkdev.h>

>  #include <linux/elevator.h>

> -#include <linux/rtc.h>

>  #include <linux/pci.h>

>  #include <linux/serial.h>

>  #include <linux/if_tun.h>

> @@ -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
diff mbox series

Patch

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 <linux/compat.h>
 #include <linux/module.h>
 #include <linux/rtc.h>
 #include <linux/sched/signal.h>
@@ -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 <linux/compat.h>
 #include <linux/err.h>
 #include <linux/fs.h>
 #include <linux/init.h>
@@ -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 <linux/raw.h>
 #include <linux/blkdev.h>
 #include <linux/elevator.h>
-#include <linux/rtc.h>
 #include <linux/pci.h>
 #include <linux/serial.h>
 #include <linux/if_tun.h>
@@ -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);