These are no longer needed because there are no dprintk() call sites
in these files.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Enable watching the progress of directory encoding to capture the
timing of any issues with reading or encoding a directory. The
new tracepoint captures dirent encoding for all NFS versions.

For example, here's what a few NFSv4 directory entries might look
like:

nfsd-989   [002]   468.596265: nfsd_dirent:          fh_hash=0x5d162594 ino=2 name=.
nfsd-989   [002]   468.596267: nfsd_dirent:          fh_hash=0x5d162594 ino=1 name=..
nfsd-989   [002]   468.596299: nfsd_dirent:          fh_hash=0x5d162594 ino=3827 name=zlib.c
nfsd-989   [002]   468.596325: nfsd_dirent:          fh_hash=0x5d162594 ino=3811 name=xdiff
nfsd-989   [002]   468.596351: nfsd_dirent:          fh_hash=0x5d162594 ino=3810 name=xdiff-interface.h
nfsd-989   [002]   468.596377: nfsd_dirent:          fh_hash=0x5d162594 ino=3809 name=xdiff-interface.c
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The SETACL result encoder is exactly the same as the NFSv2
attrstatres decoder.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clean up.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clean up: Counting the bytes used by each returned directory entry
seems less brittle to me than trying to measure consumed pages after
the fact.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Refactor: Add helper function similar to nfs3svc_encode_cookie3().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

During NFSv2 and NFSv3 READDIR/PLUS operations, NFSD advances
rq_next_page to the full size of the client-requested buffer, then
releases all those pages at the end of the request. The next request
to use that nfsd thread has to refill the pages.

NFSD does this even when the dirlist in the reply is small. With
NFSv3 clients that send READDIR operations with large buffer sizes,
that can be 256 put_page/alloc_page pairs per READDIR request, even
though those pages often remain unused.

We can save some work by not releasing dirlist buffer pages that
were not used to form the READDIR Reply. I've left the NFSv2 code
alone since there are never more than three pages involved in an
NFSv2 READDIR Reply.

Eventually we should nail down why these pages need to be released
at all in order to avoid allocating and releasing pages
unnecessarily.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clean up.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The benefit of the xdr_stream helpers is that they transparently
handle encoding an XDR data item that crosses page boundaries.
Most of the open-coded logic to do that here can be eliminated.

A sub-buffer and sub-stream are set up as a sink buffer for the
directory entry encoder. As an entry is encoded, it is added to
the end of the content in this buffer/stream. The total length of
the directory list is tracked in the buffer's @len field.

When it comes time to encode the Reply, the sub-buffer is merged
into rq_res's page array at the correct place using
xdr_write_pages().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clean up: Counting the bytes used by each returned directory entry
seems less brittle to me than trying to measure consumed pages after
the fact.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Refactor: De-duplicate identical code that handles encoding of
directory offset cookies across page boundaries.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

As an additional clean up, encode_wcc_data() is removed because it
is now no longer used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Also, clean up: Rename the encoder function to match the name of
the result structure in RFC 1813, consistent with other encoder
function names in nfs3xdr.c. "diropres" is an NFSv2 thingie.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>