On Thu, May 10, 2007 at 02:12:59PM +0200, Geert Uytterhoeven wrote: > Hi, > > `hdparm -t' uses HDIO_DRIVE_CMD(null) to flush the disk's buffer. > When using it on my own block device (the new PS3 disk storage driver), hdparm > gives the following error message: > > | HDIO_DRIVE_CMD(null) (wait for flush complete) failed: Inappropriate ioctl for device > > When using it on an ATA or SCSI device, no such error message is printed. > > According to the hdparm sources, hdparm expects the HDIO_DRIVE_CMD(null) ioctl > to either succeed, or to fail with errno EINVAL. > > Apparently handling of ioctls is different for the different device types: > - ATA/SATA handle HDIO_DRIVE_CMD(null) (and a few other variants) > => fine for hdparm > - SCSI doesn't handle HDIO_DRIVE_CMD(null), and returns EINVAL > => fine for hdparm > - If a block device doesn't support the ioctl, blkdev_driver_ioctl() returns > ENOTTY > => hdparm error message > > Which one is correct? > - blkdev_ioctl()/blkdev_driver_ioctl() return -ENOTTY > - scsi_cmd_ioctl() returns -ENOTTY > - scsi_ioctl() returns -EINVAL > - cdrom_ioctl() returns -ENOSYS to mean not handled, continue > - some block layer routines return -ENOIOCTLCMD to mean not handled, continue ENOTTY is the traditional unix errno value for this ioctl is not implemented. ENOIOCTLCMD is a new fashioned code meaning about the same. In the block layer the latter should be used as generic code should handlde this. > > My questions: > 1. Does any of these have to be fixed? > 2. Shall I add a dummy HDIO_DRIVE_CMD(null) handler to my block device to > return -EINVAL? > 3. Shall I just ignore the hdparm error message? I suspect you can just ignore this. Even better send a patch to the hdparm maintainer to deal with ENOTTY aswell. - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
