When exporting NFS, we may as well use the real change attribute
returned by the original server instead of faking up a change attribute
from the ctime.

Note we can't do that by setting I_VERSION--that would also turn on the
logic in iversion.h which treats the lower bit specially, and that
doesn't make sense for NFS.

So instead we define a new export operation for filesystems like NFS
that want to manage the change attribute themselves.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Currently NFSv4_2 SSC helper, nfs_ssc, incorrectly uses GRACE_PERIOD
as its config. Fix by adding new config NFS_V4_2_SSC_HELPER which
depends on NFS_V4_2 and is automatically selected when NFSD_V4 is
enabled. Also removed the file name from a comment in nfs_ssc.c.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

I'm not sure why we're writing this out the hard way in so many places.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The set_client() was already taken care of by process_open1().

The comments here are mostly redundant with the code.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Every caller is setting this argument to false, so we don't need it.

Also cut this comment a bit and remove an unnecessary warning.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

I think this unusual use of struct compound_state could cause confusion.

It's not that much more complicated just to open-code this stateid
lookup.

The only change in behavior should be a different error return in the
case the copy is using a source stateid that is a revoked delegation,
but I doubt that matters.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[ cel: squashed in fix reported by Coverity ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

This'll be useful elsewhere.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

I think this is a better name, and I'm going to reuse elsewhere the code
that does the lookup itself.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

You can take the single-exit thing too far, I think.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Similarly, this STALE_CLIENTID check is already handled by:

nfs4_preprocess_confirmed_seqid_op()->
        nfs4_preprocess_seqid_op()->
                nfsd4_lookup_stateid()->
                        set_client()->
                                STALE_CLIENTID()

(This may cause it to return a different error in some cases where
there are multiple things wrong; pynfs test SEQ10 regressed on this
commit because of that, but I think that's the test's fault, and I've
fixed it separately.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

This STALE_CLIENTID check is redundant with the one in
lookup_clientid().

There's a difference in behavior is in case of memory allocation
failure, which I think isn't a big deal.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clean up: The rq_argpages field was removed from struct svc_rqst in
the pre-git era.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The Receive completion handler doesn't look at the contents of the
Receive buffer. The DMA sync isn't terribly expensive but it's one
less thing that needs to be done by the Receive completion handler,
which is single-threaded (per svc_xprt). This helps scalability.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

This is similar to commit e340c2d6 ("xprtrdma: Reduce the
doorbell rate (Receive)") which added Receive batching to the
client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clean up. We are not permitted to remove old proc files. Instead,
convert these variables to stubs that are only ever allowed to
display a value of zero.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Now that we have an efficient mechanism to update these two stats,
let's start maintaining them again.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Avoid the overhead of a memory bus lock cycle for counting a value
that is hardly every used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Receives are frequent events. Avoid the overhead of a memory bus
lock cycle for counting a value that is hardly every used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Setting up the proc variables is about to get more complicated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Collect some nfsd stats per export in addition to the global stats.

A new nfsdfs export_stats file is created.  It uses the same ops as the
exports file to iterate the export entries and we use the file's name to
determine the reported info per export.  For example:

 $ cat /proc/fs/nfsd/export_stats
 # Version 1.1
 # Path Client Start-time
 #	Stats
 /test	localhost	92
	fh_stale: 0
	io_read: 9
	io_write: 1

Every export entry reports the start time when stats collection
started, so stats collecting scripts can know if stats where reset
between samples.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

nfsd stats counters can be updated by concurrent nfsd threads without any
protection.

Convert some nfsd_stats and nfsd_net struct members to use percpu counters.

The longest_chain* members of struct nfsd_net remain unprotected.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Commit 501cb184 ("nfsd: rip out the raparms cache") removed the
code that updates read-ahead cache stats counters,
commit 8bbfa9f3 ("knfsd: remove the nfsd thread busy histogram")
removed code that updates the thread busy stats counters back in 2009
and code that updated filehandle cache stats was removed back in 2002.

Remove the unused stats counters from nfsd_stats struct and print
hardcoded zeros in /proc/net/rpc/nfsd.
Signed-off-by: Amir Goldstein <amir73il@gmail.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>

Since the ACL GETATTR procedure is the same as the normal GETATTR
procedure, simply re-use nfssvc_decode_fhandleargs.
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>

Now that the argument decoders for NFSv2 and NFSv3 use the
xdr_stream mechanism, the version-specific length checking logic in
nfsd_dispatch() is no longer necessary.
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>

As an additional clean up, move code not related to XDR decoding
into readdir's .pc_func call out.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Add a helper similar to nfsd3_init_dirlist_pages().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>