Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

MFC: r264845
Remove an unnecessary level of indirection for an argument.
This simplifies the code and should avoid the clang sparc
port from generating an abort() call.

MFC: r259854
The NFSv4 server would call VOP_SETATTR() with a shared locked vnode
when a Getattr for a file is done by a client other than the one that
holds the file's delegation. This would only happen when delegations
are enabled and the problem is fixed by this patch.

MFC 245508,245566,245568,245611,245909:
Various fixes to timestamps in NFS:
- Use the VA_UTIMES_NULL flag to detect when NULL was passed to utimes()
instead of comparing the desired time against the current time as a
heuristic.
- Remove unused nfs_curusec().
- Use vfs_timestamp() to set file timestamps rather than invoking
getmicrotime() or getnanotime() directly in NFS.
- Use NFSD_MONOSEC (which maps to time_uptime) instead of the seconds
portion of wall-time stamps to manage timeouts on events.
- Remove unused nd_starttime from the per-request structure in the new
NFS server.
- Use nanotime() for the modification time on a delegation to get as
precise a time as possible.
- Use time_second instead of extracting the second from a call to
getmicrotime().

MFC: r235381
Fix two cases in the new NFS server where a tsleep() is
used, when the code should actually protect the tested
variable with a mutex. Since the tsleep()s had a 10sec
timeout, the race would have only delayed the allocation
of a new clientid for a client. The sleeps will also
rarely occur, since having a callback in progress when
a client acquires a new clientid, is unlikely.
in practice, since having a callback in progress when
a fresh clientid is being acquired by a client is unlikely.

MFC r231949:
Fix found places where uio_resid is truncated to int.

Add the sysctl debug.iosize_max_clamp, enabled by default. Setting the
sysctl to zero allows to perform the SSIZE_MAX-sized i/o requests from
the usermode.

MFC r232493:
Remove unneeded cast to u_int. The values as small enough to fit into
int, beside the use of MIN macro which performs type promotions.

MFC r232494:
Instead of incomplete handling of read(2)/write(2) return values that
does not fit into registers, declare that we do not support this case
using CTASSERT(), and remove endianess-unsafe code to split return value
into td_retval.

While there, change the style of the sysctl debug.iosize_max_clamp
definition.

MFC r232495:
pipe_read(): change the type of size to int, and remove signed clamp.
pipe_write(): change the type of desiredsize back to int, its value fits.

MFC: r230100
Tai Horgan reported via email that there were two places in
the new NFSv4 server where the code follows the wrong list.
Fortunately, for these fairly rare cases, the lc_stateid[]
lists are normally empty. This patch fixes the code to
follow the correct list.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Add DEXITCODE plumbing to NFS.

Isilon has the concept of an in-memory exit-code ring that saves the last exit
code of a function and allows for stack tracing. This is very helpful when
debugging tough issues.

This patch is essentially a no-op for BSD at this point, until we upstream
the dexitcode logic itself. The patch adds DEXITCODE calls to every NFS
function that returns an errno error code. A number of code paths were also
reorganized to have single exit paths, to reduce code duplication.

Submitted by: David Kwan <dkwan@isilon.com>
Reviewed by: rmacklem
Approved by: zml (mentor)
MFC after: 2 weeks

Simple find/replace of VOP_ISLOCKED -> NFSVOPISLOCKED. This is done so that NFSVOPISLOCKED can be modified later to add enhanced logging and assertions.

Reviewed by: rmacklem
Approved by: zml (mentor)
MFC after: 2 weeks

Simple find/replace of VOP_UNLOCK -> NFSVOPUNLOCK. This is done so that NFSVOPUNLOCK can be modified later to add enhanced logging and assertions.

Reviewed by: rmacklem
Approved by: zml (mentor)
MFC after: 2 weeks

Simple find/replace of vn_lock -> NFSVOPLOCK. This is done so that NFSVOPLOCK can be modified later to add enhanced logging and assertions.

Reviewed by: rmacklem
Approved by: zml (mentor)
MFC after: 2 weeks

Fix the new NFS client so that it handles NFSv4 state
correctly during a forced dismount. This required that
the exclusive and shared (refcnt) sleep lock functions check
for MNTK_UMOUNTF before sleeping, so that they won't block
while nfscl_umount() is getting rid of the state. As
such, a "struct mount *" argument was added to the locking
functions. I believe the only remaining case where a forced
dismount can get hung in the kernel is when a thread is
already attempting to do a TCP connect to a dead server
when the krpc client structure called nr_client is NULL.
This will only happen just after a "mount -u" with options
that force a new TCP connection is done, so it shouldn't
be a problem in practice.

MFC after: 2 weeks

Add some cleanup code to the module unload operation for
the experimental NFS server, so that it doesn't leak memory
when unloaded. However, unloading the NFSv4 server is not
recommended, since all NFSv4 state will be lost by the unload
and clients will have to recover the state after a server
reload/restart as if the server crashed/rebooted.

MFC after: 2 weeks

Modify the experimental NFSv4 server so that it posts a SIGUSR2
signal to the master nfsd daemon whenever the stable restart
file has been modified. This will allow the master nfsd daemon
to maintain an up to date backup copy of the file. This is
enabled via the nfssvc() syscall, so that older nfsd daemons
will not be signaled.

Reviewed by: jhb
MFC after: 1 week

In the experimental NFS server, when converting an open-owner to a lock-owner,
start at sequence id 1 instead of 0, to match up with both Solaris and Linux.

Reviewed by: rmacklem
Approved by: zml (mentor)

Delete the NFS_STARTWRITE() and NFS_ENDWRITE() macros that
obscured vn_start_write() and vn_finished_write() for the
old OpenBSD port, since most uses have been replaced by the
correct calls.

MFC after: 12 days

Add checks for VI_DOOMED and vn_lock() failures to the
experimental NFS server, to handle the case where an
exported file system is forced dismounted while an RPC
is in progress. Further commits will fix the cases where
a mount point is used when the associated vnode isn't locked.

Reviewed by: kib
MFC after: 2 weeks

Add support for shared vnode locks for the Read operation
in the experimental NFSv4 server.

Reviewed by: kib
MFC after: 2 weeks

Fix two vnode locking problems in nfsd_recalldelegation() in the
experimental NFSv4 server. The first was a bogus use of VOP_ISLOCKED()
in a KASSERT() and the second was the need to lock the vnode for the
nfsrv_checkremove() call. Also, delete a "__unused" that was bogus,
since the argument is used.

Reviewed by: zack.kirsch at isilon.com
MFC after: 2 weeks

Disable attempts to establish a callback connection from the
experimental NFSv4 server to a NFSv4 client when delegations are not
being issued, even if the client advertises a callback path.
This avoids a problem where a Linux client advertises a
callback path that doesn't work, due to a firewall, and then
times out an Open attempt before the FreeBSD server gives up
its callback connection attempt. (Suggested by
drb at karlov.mff.cuni.cz to fix the Linux client problem that
he reported on the fs-stable mailing list.)
The server should probably have
a 1sec timeout on callback connection attempts when there are
no delegations issued to the client, but that patch will require
changes to the krpc and this serves as a work around until then.

Tested by: drb at karlov.mff.cuni.cz
MFC after: 5 days

Try and make the nfsrv_localunlock() function in the experimental
NFSv4 server more readable. Mostly changes to comments, but a
case of >= is changed to >, since == can never happen. Also, I've
added a couple of KASSERT()s and a slight optimization, since
once the "else if" case happens, subsequent locks in the list can't
have any effect. None of these changes fixes any known bug.

MFC after: 2 weeks

Fix nfsrv_freeallnfslocks() in the experimental NFSv4 server so that
it frees local locks correctly upon close. In order for
nfsrv_localunlock() to work correctly, the lock can no longer be in
the lockowner's stateid list. As such, nfsrv_freenfslock() has to
be called before nfsrv_localunlock(), to get rid of the lock structure
on the lockowner's stateid list. This only affected operation when
local locks (vfs.newnfs.enable_locallocks=1) are enabled, which is
not the default at this time.

MFC after: 1 week

This patch applies one of the two fixes suggested by
zack.kirsch at isilon.com for a race between nfsrv_freeopen()
and nfsrv_getlockfile() in the experimental NFS server that
he found during testing. Although nfsrv_freeopen() holds a
sleep lock on the lock file structure when called with
cansleep != 0, nfsrv_getlockfile() could still search the
list, once it acquired the NFSLOCKSTATE() mutex. I believe
that acquiring the mutex in nfsrv_freeopen() fixes the race.

MFC after: 2 weeks

Add acquisition of a reference count on nfsv4root_lock to the
nfsd_recalldelegation() function, since this function is called
by nfsd threads when they are handling NFSv2 or NFSv3 RPCs, where
no reference count would have been acquired.

MFC after: 2 weeks

The timer routine in the experimental NFS server did not acquire
the correct mutex when checking nfsv4root_lock. Although this
could be fixed by adding mutex lock/unlock calls, zack.kirsch at
isilon.com suggested a better fix that uses a non-blocking
acquisition of a reference count on nfsv4root_lock. This fix
allows the weird NFSLOCKSTATE(); NFSUNLOCKSTATE(); synchronization
to be deleted. This patch applies this fix.

Tested by: zack.kirsch at isilon.com
MFC after: 2 weeks

Patch the experimental NFSv4 server so that it acquires a reference
count on nfsv4rootfs_lock when dumping state, since these functions
are not called by nfsd threads. Without this reference count, it
is possible for an nfsd thread to acquire an exclusive lock on
nfsv4rootfs_lock while the dump is in progress and then change the
lists, potentially causing a crash.

Reported by: zack.kirsch at isilon.com
MFC after: 2 weeks

Delete comments related to soft clock interrupts that don't apply
to the FreeBSD port of the experimental NFSv4 server.

Submitted by: zack.kirsch at isilon.com
MFC after: 2 weeks

This patch fixes a bug in the experimental NFSv4 server where it
released a reference count on nfsv4rootfs_lock erroneously when
administrative revocation of state was done.

Submitted by: zack.kirsch at isilon.com
MFC after: 2 weeks

Fix a bogus comment that mentions lru lists that don't exist.

Reported by: zack.kirsch at isilon.com
MFC after: 2 weeks

An NFSv4 server will reply NFSERR_GRACE for non-recovery RPCs
during the grace period after startup. This grace period must
be at least the lease duration, which is typically 1-2 minutes.
It seems prudent for the experimental NFS client to wait a few
seconds before retrying such an RPC, so that the server isn't
flooded with non-recovery RPCs during recovery. This patch adds
an argument to nfs_catnap() to implement a 5 second delay
for this case.

MFC after: 1 week

This patch should fix handling of byte range locks locally
on the server for the experimental nfs server. When enabled
by setting vfs.newnfs.locallocks_enable to non-zero, the
experimental nfs server will now acquire byte range locks
on the file on behalf of NFSv4 clients, such that lock
conflicts between the NFSv4 clients and processes running
locally on the server, will be recognized and handled correctly.

MFC after: 2 weeks

Change the default value for vfs.newnfs.enable_locallocks to 0 for
the experimental NFS server, since local locking is known to be
broken and the patch to fix it is still a work in progress.

MFC after: 5 days

The test for "same client" for the experimental nfs server over NFSv4
was broken w.r.t. byte range lock conflicts when it was the same client
and the request used the open_to_lock_owner4 case, since lckstp->ls_clp
was not set. This patch fixes it by using "clp" instead of "lckstp->ls_clp".

MFC after: 2 weeks

Rework the credential code to support larger values of NGROUPS and
NGROUPS_MAX, eliminate ABI dependencies on them, and raise the to 1024
and 1023 respectively. (Previously they were equal, but under a close
reading of POSIX, NGROUPS_MAX was defined to be too large by 1 since it
is the number of supplemental groups, not total number of groups.)

The bulk of the change consists of converting the struct ucred member
cr_groups from a static array to a pointer. Do the equivalent in
kinfo_proc.

Introduce new interfaces crcopysafe() and crsetgroups() for duplicating
a process credential before modifying it and for setting group lists
respectively. Both interfaces take care for the details of allocating
groups array. crsetgroups() takes care of truncating the group list
to the current maximum (NGROUPS) if necessary. In the future,
crsetgroups() may be responsible for insuring invariants such as sorting
the supplemental groups to allow groupmember() to be implemented as a
binary search.

Because we can not change struct xucred without breaking application
ABIs, we leave it alone and introduce a new XU_NGROUPS value which is
always 16 and is to be used or NGRPS as appropriate for things such as
NFS which need to use no more than 16 groups. When feasible, truncate
the group list rather than generating an error.

Minor changes:
- Reduce the number of hand rolled versions of groupmember().
- Do not assign to both cr_gid and cr_groups[0].
- Modify ipfw to cache ucreds instead of part of their contents since
they are immutable once referenced by more than one entity.

Submitted by: Isilon Systems (initial implementation)
X-MFC after: never
PR: bin/113398 kern/133867

Remove the "int *" typecast for the aresid argument to vn_rdwr()
and change the type of the argument from size_t to int. This
should avoid issues on 64bit architectures.

Suggested by: kib
Approved by: kib (mentor)

Change the printf of r192595 to identify the function,
as requested by Sam.

Approved by: kib (mentor)

Modified the printf message of r192590 to remove the
possible DOS attack, as suggested by Sam.

Approved by: kib (mentor)

Change the comment at the beginning of the function to reflect the
change from panic() to printf() done by r192588.

Change the reboot panic that would have occurred if clientid
numbers wrapped around to a printf() warning of a possible
DOS attack, in the experimental nfsv4 server.

Approved by: kib (mentor)

Fix the comment at line 3711 to be consistent with the change
applied for r192537.

Approved by: kib (mentor)

Although it should never happen, all the nfsv4 server can do
when it runs out of clientids is reboot. I had replaced cpu_reboot()
with printf(), since cpu_reboot() doesn't exist for sparc64.
This change replaces the printf() with panic(), so the reboot
would occur for this highly unlikely occurrence.

Approved by: kib (mentor)

Fixed the Null callback RPCs so that they work with the new krpc. This
required two changes: setting the program and version numbers before
connect and fixing the handling of the Null Rpc case in newnfs_request().

Approved by: kib (mentor)

Add the experimental nfs subtree to the kernel, that includes
support for NFSv4 as well as NFSv2 and 3.
It lives in 3 subdirs under sys/fs:
nfs - functions that are common to the client and server
nfsclient - a mutation of sys/nfsclient that call generic functions
to do RPCs and handle state. As such, it retains the
buffer cache handling characteristics and vnode semantics that
are found in sys/nfsclient, for the most part.
nfsserver - the server. It includes a DRC designed specifically for
NFSv4, that is used instead of the generic DRC in sys/rpc.
The build glue will be checked in later, so at this point, it
consists of 3 new subdirs that should not affect kernel building.

Approved by: kib (mentor)