On 11/30/2016 05:22 PM, Damien Le Moal wrote: > Both blkdev_report_zones and blkdev_reset_zones can operate on a partition of > a zoned block device. However, the first and last zones reported for a > partition make sense only if the partition start sector and size are aligned > on the device zone size. The same applies for zone reset. Resetting the first > or the last zone of a partition straddling zones may impact neighboring > partitions. Finally, if a partition start sector is not at the beginning of a > sequential zone, it will be impossible to write to the first sectors of the > partition on a host-managed device. > Avoid all these problems and incoherencies by ignoring partitions that are not > zone aligned. > > Note: Even with CONFIG_BLK_DEV_ZONED disabled, bdev_is_zoned() will report the > correct disk zoning type (host-aware, host-managed or none) but > bdev_zone_size() will always return 0 for zoned block devices (i.e. the zone > size is unknown). So test this as a way to ensure that a zoned block device is > being handled as such. As a result, for a host-aware devices, unaligned zone > partitions will be accepted with CONFIG_BLK_DEV_ZONED disabled. That is, the > disk will be treated as a regular block device (as it should). If zoned block > device support is enabled, only aligned partitions will be accepted. This looks better, thanks. Are the zone sizes mandated by spec to be a power-of-2? -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
