Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Revert 195703 and 195821 as this special stop handling in NFS is now
implemented via VFCF_SBDRY rather than passing PBDRY to individual
sleep calls.

Add a timeout on positive name cache entries in the NFS client. That is,
we will only trust a positive name cache entry for a specified amount of
time before falling back to a LOOKUP RPC, even if the ctime for the file
handle matches the cached copy in the name cache entry. The timeout is
configured via a new 'nametimeo' mount option and defaults to 60 seconds.
It may be set to zero to disable positive name caching entirely.

Reviewed by: rmacklem
MFC after: 1 week

Fix the nlm so that it no longer depends on the regular
nfs client and, as such, can be loaded for the experimental
nfs client without the regular client.

Reviewed by: jhb
MFC after: 2 weeks

Modify the NFS clients and the NLM so that the NLM can be used
by both clients. Since the NLM uses various fields of the
nfsmount structure, those fields were extracted and put in a
separate nfs_mountcommon structure stored in sys/nfs/nfs_mountcommon.h.
This structure also has a function pointer for a function that
extracts the required information from the mount point and nfs vnode
for that particular client, for information stored differently by the
clients.

Reviewed by: jhb
MFC after: 2 weeks

Add a timeout for the negative name cache entries in the NFS client.
This avoids a bogus negative name cache entry from persisting forever
when another client creates an entry with the same name within the
same NFS server time of day clock tick. The mount option negnametimeo
can be used to override the default timeout interval on a
per-mount-point basis. Setting negnametimeo to 0 disables negative
name caching for the mount point.
I also fixed one obvious typo where args.timeo should be
args.maxgrouplist.

Submitted by: jhb (earlier version)
Reviewed by: jhb
MFC after: 2 weeks

Use PBDRY flag for msleep(9) in NFS and NLM when sleeping thread owns
kernel resources that block other threads, like vnode locks. The SIGSTOP
sent to such thread (process, rather) shall not stop it until thread
releases the resources.

Tested by: pho
Reviewed by: jhb
Approved by: re (kensmith)

Remove the old kernel RPC implementation and the NFS_LEGACYRPC option.

Approved by: re

Remove the unmaintained University of Michigan NFSv4 client from 8.x
prior to 8.0-RELEASE. Rick Macklem's new and more feature-rich NFSv234
client and server are replacing it.

Discussed with: rmacklem

Implement support for RPCSEC_GSS authentication to both the NFS client
and server. This replaces the RPC implementation of the NFS client and
server with the newer RPC implementation originally developed
(actually ported from the userland sunrpc code) to support the NFS
Lock Manager. I have tested this code extensively and I believe it is
stable and that performance is at least equal to the legacy RPC
implementation.

The NFS code currently contains support for both the new RPC
implementation and the older legacy implementation inherited from the
original NFS codebase. The default is to use the new implementation -
add the NFS_LEGACYRPC option to fall back to the old code. When I
merge this support back to RELENG_7, I will probably change this so
that users have to 'opt in' to get the new code.

To use RPCSEC_GSS on either client or server, you must build a kernel
which includes the KGSSAPI option and the crypto device. On the
userland side, you must build at least a new libc, mountd, mount_nfs
and gssd. You must install new versions of /etc/rc.d/gssd and
/etc/rc.d/nfsd and add 'gssd_enable=YES' to /etc/rc.conf.

As long as gssd is running, you should be able to mount an NFS
filesystem from a server that requires RPCSEC_GSS authentication. The
mount itself can happen without any kerberos credentials but all
access to the filesystem will be denied unless the accessing user has
a valid ticket file in the standard place (/tmp/krb5cc_<uid>). There
is currently no support for situations where the ticket file is in a
different place, such as when the user logged in via SSH and has
delegated credentials from that login. This restriction is also
present in Solaris and Linux. In theory, we could improve this in
future, possibly using Brooks Davis' implementation of variant
symlinks.

Supporting RPCSEC_GSS on a server is nearly as simple. You must create
service creds for the server in the form 'nfs/<fqdn>@<REALM>' and
install them in /etc/krb5.keytab. The standard heimdal utility ktutil
makes this fairly easy. After the service creds have been created, you
can add a '-sec=krb5' option to /etc/exports and restart both mountd
and nfsd.

The only other difference an administrator should notice is that nfsd
doesn't fork to create service threads any more. In normal operation,
there will be two nfsd processes, one in userland waiting for TCP
connections and one in the kernel handling requests. The latter
process will create as many kthreads as required - these should be
visible via 'top -H'. The code has some support for varying the number
of service threads according to load but initially at least, nfsd uses
a fixed number of threads according to the value supplied to its '-n'
option.

Sponsored by: Isilon Systems
MFC after: 1 month

Re-implement the client side of rpc.lockd in the kernel. This implementation
provides the correct semantics for flock(2) style locks which are used by the
lockf(1) command line tool and the pidfile(3) library. It also implements
recovery from server restarts and ensures that dirty cache blocks are written
to the server before obtaining locks (allowing multiple clients to use file
locking to safely share data).

Sponsored by: Isilon Systems
PR: 94256
MFC after: 2 weeks

NFS MP scaling changes.
- Eliminate the hideous nfs_sndlock that serialized NFS/TCP request senders
thru the sndlock.
- Institute a new nfs_connectlock that serializes NFS/TCP reconnects. Add
logic to wait for pending request senders to finish sending before
reconnecting. Dial down the sb_timeo for NFS/TCP sockets to 1 sec.
- Break out the nfs xid manipulation under a new nfs xid lock, rather than
over loading the nfs request lock for this purpose.
- Fix some of the locking in nfs_request.
Many thanks to Kris Kennaway for his help with this and for initiating the
MP scaling analysis and work. Kris also tested this patch thorougly.
Approved by: re@ (Ken Smith)

Refactor the NFS over UDP retransmit timeout estimation logic to allow
the estimator to be more easily tuned and maintained.

There should be no functional change except there is now a lower limit
on the retransmit timeout to prevent the client from retransmitting
faster than the server's disks can fill requests, and an upper limit
to prevent the estimator from taking to long to retransmit during a
server outage.

Reviewed by: mohan, kris, silby
Sponsored by: Network Appliance, Incorporated

Changes to make the NFS client MP safe.

Thanks to Kris Kennaway for testing and sending lots of bugs my way.

Fix a serious deadlock with the NFS client. Given a large enough
atomic write request, it can fill the buffer cache with the entirety
of that write in order to handle retries. However, it never drops
the vnode lock, or else it wouldn't be atomic, so it ends up waiting
indefinitely for more buf memory that cannot be gotten as it has it
all, and it waits in an uncancellable state.

To fix this, hibufspace is exported and scaled to a reasonable
fraction. This is used as the limit of how much of an atomic write
request by the NFS client will be handled asynchronously. If the
request is larger than this, it will be turned into a synchronous
request which won't deadlock the system. It's possible this value is
far off from what is required by some, so it shall be tunable as soon
as mount_nfs(8) learns of the new field.

The slowdown between an asynchronous and a synchronous write on NFS
appears to be on the order of 2x-4x.

General nod by: gad
MFC after: 2 weeks
More testing: wes
PR: kern/79208

/* -> /*- for license, minor formatting changes

Rewrite of the NFS client's reply handling. We now have NFS socket
upcalls which do RPC header parsing and match up the reply with the
request. NFS calls now sleep on the nfsreq structure. This enables
us to eliminate the NFS recvlock.

Submitted by: Mohan Srinivasan mohans at yahoo-inc dot com

NFS mobility PHASE I, II & III (phase VI, and V pending):

Rebind the client socket when we experience a timeout. This fixes
the case where our IP changes for some reason.

Signal a VFS event when NFS transitions from up to down and vice
versa.

Add a placeholder vfs_sysctl where we will put status reporting
shortly.

Also:
Make down NFS mounts return EIO instead of EINTR when there is a
soft timeout or force unmount in progress.

Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson

Use function pointers to remove the depenancy cross dependancy on nfs4
and the nfs3 client. Also fix some bugs that happen to be causing crashes
in both v3 and v4 introduced by the v4 import.

Submitted by: Jim Rees <rees@umich.edu>
Approved by: re

University of Michigan's Citi NFSv4 kernel client code.

Submitted by: Jim Rees <rees@umich.edu>

Now that we have a cached mount credential in struct mount, use it istead
of a private cached copy.

o Make the credential used by socreate() an explicit argument to
socreate(), rather than getting it implicitly from the thread
argument.

o Make NFS cache the credential provided at mount-time, and use
the cached credential (nfsmount->nm_cred) when making calls to
socreate() on initially connecting, or reconnecting the socket.

This fixes bugs involving NFS over TCP and ipfw uid/gid rules, as well
as bugs involving NFS and mandatory access control implementations.

Reviewed by: freebsd-arch

Cleanup and split of nfs client and server code.
This builds on the top of several repo-copies.

In preparation for deprecating CIRCLEQ macros in favor of TAILQ
macros which provide the same functionality and are a bit more
efficient, convert use of CIRCLEQ's in NFS to TAILQ's.

Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by: msmith and others

Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by: phk
Reviewed by: phk
Approved by: mdodd

Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.

$Id$ -> $FreeBSD$

When using NFSv3, use the remote server's idea of the maximum file size
rather than assuming 2^64. It may not like files that big. :-)
On the nfs server, calculate and report the max file size as the point
that the block numbers in the cache would turn negative.
(ie: 1099511627775 bytes (1TB)).

One of the things I'm worried about however, is that directory offsets
are really cookies on a NFSv3 server and can be rather large, especially
when/if the server generates the opaque directory cookies by using a local
filesystem offset in what comes out as the upper 32 bits of the 64 bit
cookie. (a server is free to do this, it could save byte swapping
depending on the native 64 bit byte order)

Obtained from: NetBSD

Allow control of the attribute cache timeouts at mount time.

We had run out of bits in the nfs mount flags, I have moved the internal
state flags into a seperate variable. These are no longer visible via
statfs(), but I don't know of anything that looks at them.

Fix all areas of the system (or at least all those in LINT) to avoid storing
socket addresses in mbufs. (Socket buffers are the one exception.) A number
of kernel APIs needed to get fixed in order to make this happen. Also,
fix three protocol families which kept PCBs in mbufs to not malloc them
instead. Delete some old compatibility cruft while we're at it, and add
some new routines in the in_cksum family.

Fix a nasty hang connected with write gathering. Also add debug print
statements to bits of the server which helped me find the hang.

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.

This is the kernel Lite/2 commit. There are some requisite userland
changes, so don't expect to be able to run the kernel as-is (very well)
without the appropriate Lite/2 userland changes.

The system boots and can mount UFS filesystems.

Untested: ext2fs, msdosfs, NFS
Known problems: Incorrect Berkeley ID strings in some files.
Mount_std mounts will not work until the getfsent
library routine is changed.

Reviewed by: various people
Submitted by: Jeffery Hsu <hsu@freebsd.org>

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Improve the queuing algorithms used by NFS' asynchronous i/o. The
existing mechanism uses a global queue for some buffers and the
vp->b_dirtyblkhd queue for others. This turns sequential writes into
randomly ordered writes to the server, affecting both read and write
performance. The existing mechanism also copes badly with hung
servers, tending to block accesses to other servers when all the iods
are waiting for a hung server.

The new mechanism uses a queue for each mount point. All asynchronous
i/o goes through this queue which preserves the ordering of requests.
A simple mechanism ensures that the iods are shared out fairly between
active mount points. This removes the sysctl variable vfs.nfs.dwrite
since the new queueing mechanism removes the old delayed write code
completely.

This should go into the 2.2 branch.

Staticize.

Completed function declarations and/or added prototypes.

Changes to support version 3 of the NFS protocol.
The version 2 support has been tested (client+server) against FreeBSD-2.0,
IRIX 5.3 and FreeBSD-current (using a loopback mount). The version 2 support
is stable AFAIK.
The version 3 support has been tested with a loopback mount and minimally
against an IRIX 5.3 server. It needs more testing and may have problems.
I have patched amd to support the new variable length filehandles although
it will still only use version 2 of the protocol.

Before booting a kernel with these changes, nfs clients will need to at least
build and install /usr/sbin/mount_nfs. Servers will need to build and
install /usr/sbin/mountd.

NFS diskless support is untested.

Obtained from: Rick Macklem <rick@snowhite.cis.uoguelph.ca>

This is a bunch of changes from NetBSD. There are a couple of bug-fixes.
But mostly it is changes to use the list-maintenance macros instead of
doing the pointer-gymnastics by hand.

Obtained from: NetBSD

More idempotency....... this is fun :-)

Added $Id$

BSD 4.4 Lite Kernel Sources