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Date: Mon, 3 Jan 2011 16:34:22 -0500 (EST)
From: Rick Macklem <rmacklem@uoguelph.ca>
To: freebsd-fs@freebsd.org
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Subject: exporting non-mpsafe file systems - VFS_NEEDSGIANT()
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Hi,

The code currently in the experimental NFS server w.r.t. handling
VFS_LOCK_GIANT()/VFS_UNLOCK_GIANT() is currently BADLY broken.
Fortunately, since the major file systems being exported are mpsafe
and don't need Giant, nobody seems to be noticing.

Since the code is ugly and not easy to fix, I'd like to just delete
it and only allow mpsafe file systems to be exported. (I looked at
ufs/zfs/nullfs/msdosfs/cs9660 and they all appear to be mpsafe.)

So does anyone know of a non-mpsafe file system that needs to be
exported or see other serious problems w.r.t. not allowing exporting
of non-mpsafe file systems?

Thanks for your input, rick