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 alexandre.belloni@bootlin.com 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/dev.c | 13 ++++++++- drivers/rtc/rtc-vr41xx.c | 10 +++++++ fs/compat_ioctl.c | 61 ++-------------------------------------- 3 files changed, 25 insertions(+), 59 deletions(-)
diff --git a/drivers/rtc/dev.c b/drivers/rtc/dev.c index 1d006ef4bb57..a63779ccc8aa 100644 --- a/drivers/rtc/dev.c +++ b/drivers/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> @@ -359,10 +360,19 @@ 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 e66d0f63cee2..62c16a3b2d5c 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, __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); @@ -192,6 +197,11 @@ 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 e6dbd956cf66..fee116e822d8 100644 --- a/fs/compat_ioctl.c +++ b/fs/compat_ioctl.c @@ -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> @@ -343,37 +342,6 @@ 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; -} - /* on ia32 l_start is on a 32-bit boundary */ #if defined(CONFIG_IA64) || defined(CONFIG_X86_64) struct space_resv_32 { @@ -457,21 +425,6 @@ 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 @@ -806,24 +759,16 @@ IGNORE_IOCTL(FBIOGCURSOR32) static long do_ioctl_trans(unsigned int cmd, unsigned long arg, struct file *file) { - void __user *argp = compat_ptr(arg); - switch (cmd) { #ifdef CONFIG_BLOCK case SG_IO: - return sg_ioctl_trans(file, cmd, argp); + return sg_ioctl_trans(file, cmd, compat_ptr(arg)); case SG_GET_REQUEST_TABLE: - return sg_grt_trans(file, cmd, argp); + return sg_grt_trans(file, cmd, compat_ptr(arg)); case MTIOCGET32: case MTIOCPOS32: - return mt_ioctl_trans(file, cmd, argp); + return mt_ioctl_trans(file, cmd, compat_ptr(arg)); #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); }
/*