compat_ioctl: move CDROMREADADIO to cdrom.c

Again, there is only one file that needs this, so move the conversion
handler into the native implementation.
Reviewed-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

block/compat_ioctl.c

@@ -96,40 +96,6 @@ static int compat_hdio_ioctl(struct block_device *bdev, fmode_t mode,
 	return error;
 }
 
-struct compat_cdrom_read_audio {
-	union cdrom_addr	addr;
-	u8			addr_format;
-	compat_int_t		nframes;
-	compat_caddr_t		buf;
-};
-
-static int compat_cdrom_read_audio(struct block_device *bdev, fmode_t mode,
-		unsigned int cmd, unsigned long arg)
-{
-	struct cdrom_read_audio __user *cdread_audio;
-	struct compat_cdrom_read_audio __user *cdread_audio32;
-	__u32 data;
-	void __user *datap;
-
-	cdread_audio = compat_alloc_user_space(sizeof(*cdread_audio));
-	cdread_audio32 = compat_ptr(arg);
-
-	if (copy_in_user(&cdread_audio->addr,
-			 &cdread_audio32->addr,
-			 (sizeof(*cdread_audio32) -
-			  sizeof(compat_caddr_t))))
-		return -EFAULT;
-
-	if (get_user(data, &cdread_audio32->buf))
-		return -EFAULT;
-	datap = compat_ptr(data);
-	if (put_user(datap, &cdread_audio->buf))
-		return -EFAULT;
-
-	return __blkdev_driver_ioctl(bdev, mode, cmd,
-			(unsigned long)cdread_audio);
-}
-
 struct compat_blkpg_ioctl_arg {
 	compat_int_t op;
 	compat_int_t flags;
@@ -179,8 +145,6 @@ static int compat_blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
 	case HDIO_GET_ADDRESS:
 	case HDIO_GET_BUSSTATE:
 		return compat_hdio_ioctl(bdev, mode, cmd, arg);
-	case CDROMREADAUDIO:
-		return compat_cdrom_read_audio(bdev, mode, cmd, arg);
 
 	/*
 	 * No handler required for the ones below, we just need to

drivers/cdrom/cdrom.c

@@ -3017,9 +3017,31 @@ static noinline int mmc_ioctl_cdrom_read_audio(struct cdrom_device_info *cdi,
 	struct cdrom_read_audio ra;
 	int lba;
 
-	if (copy_from_user(&ra, (struct cdrom_read_audio __user *)arg,
-			   sizeof(ra)))
-		return -EFAULT;
+#ifdef CONFIG_COMPAT
+	if (in_compat_syscall()) {
+		struct compat_cdrom_read_audio {
+			union cdrom_addr	addr;
+			u8			addr_format;
+			compat_int_t		nframes;
+			compat_caddr_t		buf;
+		} ra32;
+
+		if (copy_from_user(&ra32, arg, sizeof(ra32)))
+			return -EFAULT;
+
+		ra = (struct cdrom_read_audio) {
+			.addr		= ra32.addr,
+			.addr_format	= ra32.addr_format,
+			.nframes	= ra32.nframes,
+			.buf		= compat_ptr(ra32.buf),
+		};
+	} else
+#endif
+	{
+		if (copy_from_user(&ra, (struct cdrom_read_audio __user *)arg,
+				   sizeof(ra)))
+			return -EFAULT;
+	}
 
 	if (ra.addr_format == CDROM_MSF)
 		lba = msf_to_lba(ra.addr.msf.minute,