The new NFSv4 client handled NFSERR_GRACE as a fatal error for the remove and rename operations. Some NFSv4 servers will report NFSERR_GRACE for these operations. This patch changes the behaviour of the client so that it handles NFSERR_GRACE like NFSERR_DELAY for non-state related operations like remove and rename. It also exempts the delegreturn operation from handling within newnfs_request() for NFSERR_DELAY/NFSERR_GRACE so that it can handle NFSERR_GRACE in the same manner as before. This problem was resolved thanks to discussion with bfields at fieldses.org. The problem was identified at the recent NFSv4 ineroperability bakeathon.
The new NFSv4 client handled NFSERR_GRACE as a fatal error
for the remove and rename operations. Some NFSv4 servers will
report NFSERR_GRACE for these operations. This patch changes
the behaviour of the client so that it handles NFSERR_GRACE
like NFSERR_DELAY for non-state related operations like
remove and rename. It also exempts the delegreturn operation
from handling within newnfs_request() for NFSERR_DELAY/NFSERR_GRACE
so that it can handle NFSERR_GRACE in the same manner as before.
This problem was resolved thanks to discussion with bfields at fieldses.org.
The problem was identified at the recent NFSv4 ineroperability
bakeathon.

MFC after:	2 weeks

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