Ok, ok, a few more words about it: stop holding puffs_cc as a holy
value and passing it around to almost every possible place (popquiz:
which kernel variable does this remind you of?). Instead, pass
the natural choice, puffs_usermount, and fetch puffs_cc via
puffs_cc_getcc() only in routines which actually need it. This
not only simplifies code, but (thanks to the introduction of
puffs_cc_getcc()) enables constructs which weren't previously sanely
possible, say layering as a curious example.
There's still a little to do on this front, but this was the major
fs interface blast.
a directory hierarchy to another point, just like with the kernel
nullfs. This is not really a layering scheme yet, but it should
evolve into one. Currently it can just be used to do 1:1 mapping.
server that it needs to mount the file system backend if it wants
to call mount
* provide some options for getmntopts(), assume that callers will parse
command line (or fstab) args
* reorganize the puffs_cc interface just a bit, preparing for a bigger
revamp later
Add support for having multiple outstanding operations. This is done
by exposing enough interfaces so that it is convenient to have the
main event loop in the implementation itself and by providing a
continuation framework for convinient blocking and rescheduling.
works fine, but will undergo further cleanup & development
This work was initially started and completed for Google SoC 2005
and tweaked to work a bit better in the past few weeks. While
being far from complete, it is functional enough to be able and
stable to host a fairly general-purpose in-memory file system in
userspace. Even so, puffs should be considered experimental and
no binary compatibility for interfaces or crash-freedom or zero
security implications should be relied upon just yet.
The GSoC project was mentored by William Studenmund and the final
review for the code was done by Christos.