diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2018-08-24 00:11:19 +0200 |
|---|---|---|
| committer | Arnd Bergmann <arnd@arndb.de> | 2019-10-23 17:23:43 +0200 |
| commit | 076ff658628678f73d2349a699c3431877c1a075 (patch) | |
| tree | caca2f4897a396b9dad82af56a87b4c0be8876f8 /drivers/rtc/dev.c | |
| parent | 18bd6caaef4021803dd0d031dc37c2d001d18a5b (diff) | |
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: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd 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.
Diffstat (limited to 'drivers/rtc/dev.c')
| -rw-r--r-- | drivers/rtc/dev.c | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c index 84feb2565abd..5b8ebe86124a 100644 --- a/drivers/rtc/dev.c +++ b/drivers/rtc/dev.c @@ -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, |