compat_ioctl: add compat_blkdev_driver_ioctl()

Handle those blockdev ioctl calls that are compatible
directly from the compat_blkdev_ioctl() function, instead
of having to go through the compat_ioctl hash lookup.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 120 insertions, 1 deletions

diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index d20fdb4..500cc9e 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -40,6 +40,122 @@ static int compat_put_u64(unsigned long arg, u64 val)
 #define BLKBSZSET_32		_IOW(0x12, 113, int)
 #define BLKGETSIZE64_32		_IOR(0x12, 114, int)
 
+static int compat_blkdev_driver_ioctl(struct inode *inode, struct file *file,
+			struct gendisk *disk, unsigned cmd, unsigned long arg)
+{
+	int ret;
+
+	switch (arg) {
+	/*
+	 * No handler required for the ones below, we just need to
+	 * convert arg to a 64 bit pointer.
+	 */
+	case BLKSECTSET:
+	/*
+	 * 0x03 -- HD/IDE ioctl's used by hdparm and friends.
+	 *         Some need translations, these do not.
+	 */
+	case HDIO_GET_IDENTITY:
+	case HDIO_DRIVE_TASK:
+	case HDIO_DRIVE_CMD:
+	case HDIO_SCAN_HWIF:
+	/* 0x330 is reserved -- it used to be HDIO_GETGEO_BIG */
+	case 0x330:
+	/* 0x02 -- Floppy ioctls */
+	case FDMSGON:
+	case FDMSGOFF:
+	case FDSETEMSGTRESH:
+	case FDFLUSH:
+	case FDWERRORCLR:
+	case FDSETMAXERRS:
+	case FDGETMAXERRS:
+	case FDGETDRVTYP:
+	case FDEJECT:
+	case FDCLRPRM:
+	case FDFMTBEG:
+	case FDFMTEND:
+	case FDRESET:
+	case FDTWADDLE:
+	case FDFMTTRK:
+	case FDRAWCMD:
+	/* CDROM stuff */
+	case CDROMPAUSE:
+	case CDROMRESUME:
+	case CDROMPLAYMSF:
+	case CDROMPLAYTRKIND:
+	case CDROMREADTOCHDR:
+	case CDROMREADTOCENTRY:
+	case CDROMSTOP:
+	case CDROMSTART:
+	case CDROMEJECT:
+	case CDROMVOLCTRL:
+	case CDROMSUBCHNL:
+	case CDROMMULTISESSION:
+	case CDROM_GET_MCN:
+	case CDROMRESET:
+	case CDROMVOLREAD:
+	case CDROMSEEK:
+	case CDROMPLAYBLK:
+	case CDROMCLOSETRAY:
+	case CDROM_DISC_STATUS:
+	case CDROM_CHANGER_NSLOTS:
+	case CDROM_GET_CAPABILITY:
+	/* Ignore cdrom.h about these next 5 ioctls, they absolutely do
+	 * not take a struct cdrom_read, instead they take a struct cdrom_msf
+	 * which is compatible.
+	 */
+	case CDROMREADMODE2:
+	case CDROMREADMODE1:
+	case CDROMREADRAW:
+	case CDROMREADCOOKED:
+	case CDROMREADALL:
+	/* DVD ioctls */
+	case DVD_READ_STRUCT:
+	case DVD_WRITE_STRUCT:
+	case DVD_AUTH:
+		arg = (unsigned long)compat_ptr(arg);
+	/* These intepret arg as an unsigned long, not as a pointer,
+	 * so we must not do compat_ptr() conversion. */
+	case HDIO_SET_MULTCOUNT:
+	case HDIO_SET_UNMASKINTR:
+	case HDIO_SET_KEEPSETTINGS:
+	case HDIO_SET_32BIT:
+	case HDIO_SET_NOWERR:
+	case HDIO_SET_DMA:
+	case HDIO_SET_PIO_MODE:
+	case HDIO_SET_NICE:
+	case HDIO_SET_WCACHE:
+	case HDIO_SET_ACOUSTIC:
+	case HDIO_SET_BUSSTATE:
+	case HDIO_SET_ADDRESS:
+	case CDROMEJECT_SW:
+	case CDROM_SET_OPTIONS:
+	case CDROM_CLEAR_OPTIONS:
+	case CDROM_SELECT_SPEED:
+	case CDROM_SELECT_DISC:
+	case CDROM_MEDIA_CHANGED:
+	case CDROM_DRIVE_STATUS:
+	case CDROM_LOCKDOOR:
+	case CDROM_DEBUG:
+		break;
+	default:
+		/* unknown ioctl number */
+		return -ENOIOCTLCMD;
+	}
+
+	if (disk->fops->unlocked_ioctl)
+		return disk->fops->unlocked_ioctl(file, cmd, arg);
+
+	if (disk->fops->ioctl) {
+		lock_kernel();
+		ret = disk->fops->ioctl(inode, file, cmd, arg);
+		unlock_kernel();
+		return ret;
+	}
+
+	return -ENOTTY;
+}
+
 static int compat_blkdev_locked_ioctl(struct inode *inode, struct file *file,
 				struct block_device *bdev,
 				unsigned cmd, unsigned long arg)
@@ -117,5 +233,8 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 		ret = disk->fops->compat_ioctl(file, cmd, arg);
 	unlock_kernel();
 
-	return ret;
+	if (ret != -ENOIOCTLCMD)
+		return ret;
+
+	return compat_blkdev_driver_ioctl(inode, file, disk, cmd, arg);
 }