User Space File Systems

“I’ve been writing a fair amount on file systems in Linux
because I think we are in the midst of a file system Renaissance.
We are seeing new file systems added to the kernel coupled with
increasingly enterprise class features giving us more options than
ever before. What is even more remarkable is that not too long ago
Linux file system development was almost non-existent and in a few
short years we have so much development and testing happening (for
a brief commentary on that, read the interview with Valerie
Aurora).

“But getting file systems into the kernel is a very long and
arduous process. It is complicated, difficult work that takes a
great deal of determination. This usually means that file systems
won’t address a niche requirement that is needed by a segment of
Linux users, but instead will be general file systems addressing
the broader Linux market. But what if you wanted to create a file
system so you could take compressed tar files (.tar.gz) and mount
them as a file system so you can easily read and write to them? Or
what if you wanted to be able to mount remote file systems using
secure tools such as ssh or sftp? I think even if you wrote some
very conforming Linux kernel code to address file system need such
as this, it would take a very long time for them to be added to the
kernel if they are included at all (it’s likely they would not
because they are more niche than mainstream).”

Complete
Story