zonefs: Mapping POSIX File System Interface to Raw Zoned Block Device Accesses

Due to travel restrictions, Damien Le Moal and Ting Yao could not attend the conference and their work was presented by Matias Bjørling, Western Digital, Inc.

zonefs is a new file system being proposed for inclusion in the Linux kernel. zonefs exposes zones of a zoned block device as files to allow simplifying application use of these type of storage devices. zonefs is not a full-featured POSIX compliant file system and is intended to replace and simplify device use cases where raw block device accesses are a better solution. This talk will present zonefs features, with a focus on how the rich POSIX system call interface is used and mapped to directly issue device specific control commands to zoned block devices. An example use of zonefs in LevelDB will be shown and the advantages in term of code simplicity over regular block device file access shown. Finally, we will discuss how zonefs can be extended to also support new types of zoned storage devices such as NVMe Zoned Namespace (ZNS) SSDs.