Anyone porting YAFFS2?

[M. Warner Losh]

In message: <46549AE9.9040505 at incunabulum.net>
            "Bruce M. Simpson" <bms at incunabulum.net> writes:
: Has anyone out there considered porting YAFFS2 to FreeBSD? Looking at 
: the design notes it sounds fairly portable, more so than JFFS2: 
: http://www.aleph1.co.uk/taxonomy/term/31/
: 
: This could be a good test case for flash support as it seems that a 
: NEWBUS interface could be implemented for flash controllers, which 
: YAFFS2 could then use.

I'm not sure a newbus interface is the right one to use, since most
storage systems are built on the bio interface.  We'd have to flush
out the bio interface to cope.  However, I think most of the things
that are necessary already exist in the interface...

: I'm not sure how GEOM would fit into this picture. The file system glue 
: strikes me as a minimal amount of work compared to the rest involved in 
: supporting this.

There's already a geom_nand floating around in the while.  It does the
wear averaging, but is somewhat tied to some specific hardware and
isn't done generically, and I'm not sure if I can give it out...

: Whilst the code is available under GPL, the author(s) state that they 
: are 'open to arrangements'; I'm not sure what this implies, the 
: licensing information on their site suggests this is about negotiating 
: commercial licenses with them. It would seem acceptable to me that such 
: code could potentially be imported under src/sys/contrib, however, this 
: leaves the question of what we do about firmware images which 
: incorporate such a YAFFS2 build.

GPL'd code is fine, so long as it is in src/sys/gnu.

Warner