K 10
svn:author
V 7
rwatson
K 8
svn:date
V 27
2006-11-24T11:53:16.000000Z
K 7
svn:log
V 915
Push Giant a bit further off the NFS server in a number of straight
forward cases by converting from unconditional acquisition of Giant
around vnode operations to conditional acquisition:

- Remove nfsrv_access_withgiant(), and cause nfsrv_access() to now
  assert that Giant will be held if it is required for the vnode.

- Add nfsrv_fhtovp_locked(), which will drop the NFS server lock if
  required, and modify nfsrv_fhtovp() to conditionally acquire
  Giant if required.

- In the VOP's not dealing with more than one vnode at a time (i.e.,
  not involving a lookup), conditionally acquire Giant.

This removes Giant use for MPSAFE file systems for a number of quite
important RPCs, including getattr, read, write.  It leaves
unconditional Giant acquisitions in vnode operations that interact
with the name space or more than one vnode at a time as these
require further work.

Tested by:	kris
Reviewed by:	kib

END