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: r265252
The new draft specification for NFSv4.0 specifies that a server
should either accept owner and owner_group strings that are just
the digits of the uid/gid or return NFS4ERR_BADOWNER.
This patch adds a sysctl vfs.nfsd.enable_stringtouid, which can
be set to enable the server w.r.t. accepting numeric string. It
also ensures that NFS4ERR_BADOWNER is returned if numeric uid/gid
strings are not enabled. This fixes the server for recent Linux
nfs4 clients that use numeric uid/gid strings by default.

MFC: r264672
Modify the Lookup RPC for NFSv4 so that it acquires directory
attributes. This allows the client to cache directory names
when they are looked up, reducing the Lookup RPC count by
about 40% for software builds.

MFC: r259801
The NFSv4 client was passing both the p and cred arguments to
nfsv4_fillattr() as NULLs for the Getattr callback. This caused
nfsv4_fillattr() to not fill in the Change attribute for the reply.
I believe this was a violation of the RFC, but had little effect on
server behaviour. This patch passes a non-NULL p argument to fix this.

MFC: r253506
The NFSv4 server incorrectly assumed that the high order words of
the attribute bitmap argument would be non-zero. This caused an
interoperability problem for a recent patch to the Linux NFSv4 client.
The Linux folks have changed their patch to avoid this, but this
patch fixes the problem on the server.

Reported and tested by: a.heider@gmail.com (Andre Heider)
Approved by: re (Xin Li)

MFC NFS FHA changes 249592 and 249596:

------------------------------------------------------------------------
r249592 | ken | 2013-04-17 15:00:22 -0600 (Wed, 17 Apr 2013) | 180 lines

Revamp the old NFS server's File Handle Affinity (FHA) code so that
it will work with either the old or new server.

The FHA code keeps a cache of currently active file handles for
NFSv2 and v3 requests, so that read and write requests for the same
file are directed to the same group of threads (reads) or thread
(writes). It does not currently work for NFSv4 requests. They are
more complex, and will take more work to support.

This improves read-ahead performance, especially with ZFS, if the
FHA tuning parameters are configured appropriately. Without the
FHA code, concurrent reads that are part of a sequential read from
a file will be directed to separate NFS threads. This has the
effect of confusing the ZFS zfetch (prefetch) code and makes
sequential reads significantly slower with clients like Linux that
do a lot of prefetching.

The FHA code has also been updated to direct write requests to nearby
file offsets to the same thread in the same way it batches reads,
and the FHA code will now also send writes to multiple threads when
needed.

This improves sequential write performance in ZFS, because writes
to a file are now more ordered. Since NFS writes (generally
less than 64K) are smaller than the typical ZFS record size
(usually 128K), out of order NFS writes to the same block can
trigger a read in ZFS. Sending them down the same thread increases
the odds of their being in order.

In order for multiple write threads per file in the FHA code to be
useful, writes in the NFS server have been changed to use a LK_SHARED
vnode lock, and upgrade that to LK_EXCLUSIVE if the filesystem
doesn't allow multiple writers to a file at once. ZFS is currently
the only filesystem that allows multiple writers to a file, because
it has internal file range locking. This change does not affect the
NFSv4 code.

This improves random write performance to a single file in ZFS, since
we can now have multiple writers inside ZFS at one time.

I have changed the default tuning parameters to a 22 bit (4MB)
window size (from 256K) and unlimited commands per thread as a
result of my benchmarking with ZFS.

The FHA code has been updated to allow configuring the tuning
parameters from loader tunable variables in addition to sysctl
variables. The read offset window calculation has been slightly
modified as well. Instead of having separate bins, each file
handle has a rolling window of bin_shift size. This minimizes
glitches in throughput when shifting from one bin to another.

sys/conf/files:
Add nfs_fha_new.c and nfs_fha_old.c. Compile nfs_fha.c
when either the old or the new NFS server is built.

sys/fs/nfs/nfsport.h,
sys/fs/nfs/nfs_commonport.c:
Bring in changes from Rick Macklem to newnfs_realign that
allow it to operate in blocking (M_WAITOK) or non-blocking
(M_NOWAIT) mode.

sys/fs/nfs/nfs_commonsubs.c,
sys/fs/nfs/nfs_var.h:
Bring in a change from Rick Macklem to allow telling
nfsm_dissect() whether or not to wait for mallocs.

sys/fs/nfs/nfsm_subs.h:
Bring in changes from Rick Macklem to create a new
nfsm_dissect_nonblock() inline function and
NFSM_DISSECT_NONBLOCK() macro.

sys/fs/nfs/nfs_commonkrpc.c,
sys/fs/nfsclient/nfs_clkrpc.c:
Add the malloc wait flag to a newnfs_realign() call.

sys/fs/nfsserver/nfs_nfsdkrpc.c:
Setup the new NFS server's RPC thread pool so that it will
call the FHA code.

Add the malloc flag argument to newnfs_realign().

Unstaticize newnfs_nfsv3_procid[] so that we can use it in
the FHA code.

sys/fs/nfsserver/nfs_nfsdsocket.c:
In nfsrvd_dorpc(), add NFSPROC_WRITE to the list of RPC types
that use the LK_SHARED lock type.

sys/fs/nfsserver/nfs_nfsdport.c:
In nfsd_fhtovp(), if we're starting a write, check to see
whether the underlying filesystem supports shared writes.
If not, upgrade the lock type from LK_SHARED to LK_EXCLUSIVE.

sys/nfsserver/nfs_fha.c:
Remove all code that is specific to the NFS server
implementation. Anything that is server-specific is now
accessed through a callback supplied by that server's FHA
shim in the new softc.

There are now separate sysctls and tunables for the FHA
implementations for the old and new NFS servers. The new
NFS server has its tunables under vfs.nfsd.fha, the old
NFS server's tunables are under vfs.nfsrv.fha as before.

In fha_extract_info(), use callouts for all server-specific
code. Getting file handles and offsets is now done in the
individual server's shim module.

In fha_hash_entry_choose_thread(), change the way we decide
whether two reads are in proximity to each other.
Previously, the calculation was a simple shift operation to
see whether the offsets were in the same power of 2 bucket.
The issue was that there would be a bucket (and therefore
thread) transition, even if the reads were in close
proximity. When there is a thread transition, reads wind
up going somewhat out of order, and ZFS gets confused.

The new calculation simply tries to see whether the offsets
are within 1 << bin_shift of each other. If they are, the
reads will be sent to the same thread.

The effect of this change is that for sequential reads, if
the client doesn't exceed the max_reqs_per_nfsd parameter
and the bin_shift is set to a reasonable value (22, or
4MB works well in my tests), the reads in any sequential
stream will largely be confined to a single thread.

Change fha_assign() so that it takes a softc argument. It
is now called from the individual server's shim code, which
will pass in the softc.

Change fhe_stats_sysctl() so that it takes a softc
parameter. It is now called from the individual server's
shim code. Add the current offset to the list of things
printed out about each active thread.

Change the num_reads and num_writes counters in the
fha_hash_entry structure to 32-bit values, and rename them
num_rw and num_exclusive, respectively, to reflect their
changed usage.

Add an enable sysctl and tunable that allows the user to
disable the FHA code (when vfs.XXX.fha.enable = 0). This
is useful for before/after performance comparisons.

nfs_fha.h:
Move most structure definitions out of nfs_fha.c and into
the header file, so that the individual server shims can
see them.

Change the default bin_shift to 22 (4MB) instead of 18
(256K). Allow unlimited commands per thread.

sys/nfsserver/nfs_fha_old.c,
sys/nfsserver/nfs_fha_old.h,
sys/fs/nfsserver/nfs_fha_new.c,
sys/fs/nfsserver/nfs_fha_new.h:
Add shims for the old and new NFS servers to interface with
the FHA code, and callbacks for the

The shims contain all of the code and definitions that are
specific to the NFS servers.

They setup the server-specific callbacks and set the server
name for the sysctl and loader tunable variables.

sys/nfsserver/nfs_srvkrpc.c:
Configure the RPC code to call fhaold_assign() instead of
fha_assign().

sys/modules/nfsd/Makefile:
Add nfs_fha.c and nfs_fha_new.c.

sys/modules/nfsserver/Makefile:
Add nfs_fha_old.c.

Reviewed by: rmacklem
Sponsored by: Spectra Logic

------------------------------------------------------------------------
r249596 | ken | 2013-04-17 16:42:43 -0600 (Wed, 17 Apr 2013) | 7 lines

Move the NFS FHA (File Handle Affinity) code from sys/nfsserver to
sys/nfs, since it is now shared by the two NFS servers.

Suggested by: rmacklem
Sponsored by: Spectra Logic
------------------------------------------------------------------------

Sponsored by: Spectra Logic

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 r246213:
Assert that the mbuf in the chain has sane length.

MFC: r240720
Modify the NFSv4 client so that it can handle owner
and owner_group strings that consist entirely of
digits, interpreting them as the uid/gid number.
This change was needed since new (>= 3.3) Linux
servers reply with these strings by default.
This change is mandated by the rfc3530bis draft.
Reported on freebsd-stable@ under the Subject
heading "Problem with Linux >= 3.3 as NFSv4 server"
by Norbert Aschendorff on Aug. 20, 2012.

MFC: r229802
opt_inet6.h was missing from some files in the new NFS subsystem.
The effect of this was, for clients mounted via inet6 addresses,
that the DRC cache would never have a hit in the server. It also
broke NFSv4 callbacks when an inet6 address was the only one available
in the client. This patch fixes the above, plus deletes opt_inet6.h
from a couple of files it is not needed for.

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

Approved by: re (implicit)

Revert revision 224079 as Rick pointed out that I would be calling VOP_PATHCONF
without the vnode lock held.

Implicitly approved by: zml (mentor)

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_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

Change loadattr and fillattr to ask the file system for the pathconf variable.

Small modification where VOP_PATHCONF was being called directly.

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

Small acl patch to return the aclerror that comes back from nfsrv_dissectacl(). This fixes a problem where ATTRNOTSUPP was being returned instead of BADOWNER.

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

Fix the experimental NFSv4 server so that it uses VOP_PATHCONF()
to determine if a file system supports NFSv4 ACLs. Since
VOP_PATHCONF() must be called with a locked vnode, the function
is called before nfsvno_fillattr() and the result is passed in
as an extra argument.

MFC after: 2 weeks

Modify the experimental NFSv4 server so that it handles
crossing of server mount points properly. The functions
nfsvno_fillattr() and nfsv4_fillattr() were modified to
take the extra arguments that are the mount point, a flag
to indicate that it is a file system root and the mounted
on fileno. The mount point argument needs to be busy when
nfsvno_fillattr() is called, since the vp argument is not
locked.

Reviewed by: kib
MFC after: 2 weeks

Fix the experimental NFSv4 server so that it uses VOP_ACCESSX()
to check for VREAD_ACL instead of VOP_ACCESS().

MFC after: 3 days

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

Reviewed by: kib
MFC after: 2 weeks

Modify the experimental NFS server so that it uses LK_SHARED
for RPC operations when it can. Since VFS_FHTOVP() currently
always gets an exclusively locked vnode and is usually called
at the beginning of each RPC, the RPCs for a given vnode will
still be serialized. As such, passing a lock type argument to
VFS_FHTOVP() would be preferable to doing the vn_lock() with
LK_DOWNGRADE after the VFS_FHTOVP() call.

Reviewed by: kib
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

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

Remove unneeded ifdefs.

Reviewed by: rmacklem

Fix the experimental nfs subsystem so that it builds with the
current NFSv4 ACLs, as defined in sys/acl.h. It still needs a
way to test a mount point for NFSv4 ACL support before it will
work. Until then, the NFSHASNFS4ACL() macro just always returns 0.

Approved by: kib (mentor)

Remove the thread argument from the FSD (File-System Dependent) parts of
the VFS. Now all the VFS_* functions and relating parts don't want the
context as long as it always refers to curthread.

In some points, in particular when dealing with VOPs and functions living
in the same namespace (eg. vflush) which still need to be converted,
pass curthread explicitly in order to retain the old behaviour.
Such loose ends will be fixed ASAP.

While here fix a bug: now, UFS_EXTATTR can be compiled alone without the
UFS_EXTATTR_AUTOSTART option.

VFS KPI is heavilly changed by this commit so thirdy parts modules needs
to be recompiled. Bump __FreeBSD_version in order to signal such
situation.

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)