MFC: r268273
The new NFSv3 server did not generate directory postop attributes for
the reply to ReaddirPlus when the server failed within the loop
that calls VFS_VGET(). This failure is most likely an error
return from VFS_VGET() caused by a bogus d_fileno that was
truncated to 32bits.
This patch fixes the server so that it will return directory postop
attributes for the failure. It does not fix the underlying issue caused
by d_fileno being uint32_t when a file system like ZFS generates
a fileno that is greater than 32bits.

(cherry picked from commit aa183af4c50f5e86138c443fa9a0513a226d2d27)

Ticket: #7186
MFC: r269771
Change the NFS server's printf related to hitting
the DRC cache's flood level so that it suggests
increasing vfs.nfsd.tcphighwater.

(cherry picked from commit a5a0eb4e54a9a50abf21c09dbf97297c3ce968d8)
Fix failures and warnings reported by newpynfs20090424 test tool.
This fix addresses only issues with the pynfs reports, none of these
issues are know to create problems for extant real clients.

Submitted by:	Bart Hsiao <bart.hsiao@gmail.com>
Reworked by:	myself
Reviewed by:	rmacklem
Approved by:	rmacklem
Sponsored by:	QNAP Systems Inc.

(cherry picked from commit 4100d9b0a6e30d123b227ff156169bf4567cc1d9)