History log of /freebsd-11-stable/sys/fs/nfsserver/nfs_nfsdsocket.c
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# 361236 19-May-2020 freqlabs

MFC r360960:

nfs: Remove APPLESTATIC macro

It is no longer useful.

Reviewed by: rmacklem
Approved by: mav (mentor)
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D24811


# 361070 15-May-2020 freqlabs

MFC r360813:

Remove APPLEKEXT ifndefs

They are no longer useful.

Reviewed by: rmacklem
Approved by: mav (mentor)
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D24752


# 340852 23-Nov-2018 emaste

MFC r340661 (rmacklem):

r304026 added code that started statistics gathering for an operation
before the operation number (the variable called "op") was sanity checked.
This patch moves the code down to below the range sanity check for "op".


# 336842 28-Jul-2018 rmacklem

MFC: r334492
Add the BindConnectiontoSession operation to the NFSv4.1 server.

Under some fairly unusual circumstances, the Linux NFSv4.1 client is
doing a BindConnectiontoSession operation for TCP connections.
It is also used by the ESXi6.5 NFSv4.1 client.
This patch adds this operation to the NFSv4.1 server.

PR: 226493


# 336178 10-Jul-2018 rmacklem

MFC: r333508
Add support for the TestStateID operation to the NFSv4.1 server.

The Linux client now uses the TestStateID operation, so this patch adds
support for it to the NFSv4.1 server. The FreeBSD client never uses this
operation, so it should not be affected.


# 331722 29-Mar-2018 eadler

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)


# 330897 14-Mar-2018 eadler

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg


# 306609 02-Oct-2016 rmacklem

MFC: r304026
Update the nfsstats structure to include the changes needed by
the patch in D1626 plus changes so that it includes counts for
NFSv4.1 (and the draft of NFSv4.2).
Also, make all the counts uint64_t and add a vers field at the
beginning, so that future revisions can easily be implemented.
There is code in place to handle the old vesion of the nfsstats
structure for backwards binary compatibility.

Subsequent commits will update nfsstat(8) to use the new fields.


# 302408 07-Jul-2016 gjb

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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


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# 299226 07-May-2016 rmacklem

Don't increment srvrpccnt[] for the NFSv4.1 operations.

When support for NFSv4.1 was added to the NFS server, it broke
the server rpc count stats, since newnfsstats.srvrpccnt[] doesn't
have entries for the new NFSv4.1 operations.
Without this patch, the code was incrementing bogus entries in
newnfsstats for the new NFSv4.1 operations.
This patch is an interim fix. The nfsstats structure needs to be
updated and that will come in a future commit.

Reported by: cem
MFC after: 2 weeks


# 297793 10-Apr-2016 pfg

Cleanup unnecessary semicolons from the kernel.

Found with devel/coccinelle.


# 283753 29-May-2015 rmacklem

Make the NFS server use shared vnode locks for a few cases
that are allowed by the VFS/VOP interface instead of using
exclusive locks.

MFC after: 2 weeks


# 283635 27-May-2015 rmacklem

Make the size of the hash tables used by the NFSv4 server tunable.
No appreciable change in performance was observed after increasing
the sizes of these tables and then testing with a single client.
However, there was an email that indicated high CPU overheads for
a heavily loaded NFSv4 and it is hoped that increasing the sizes
of the hash tables via these tunables might help.
The tables remain the same size by default.

Differential Revision: https://reviews.freebsd.org/D2596
MFC after: 2 weeks


# 269771 09-Aug-2014 rmacklem

Change the NFS server's printf related to hitting
the DRC cache's flood level so that it suggests
increasing vfs.nfsd.tcphighwater.

Suggested by: h.schmalzbauer@omnilan.de


# 268115 01-Jul-2014 rmacklem

Merge the NFSv4.1 server code in projects/nfsv4.1-server over
into head. The code is not believed to have any effect
on the semantics of non-NFSv4.1 server behaviour.
It is a rather large merge, but I am hoping that there will
not be any regressions for the NFS server.

MFC after: 1 month


# 249592 17-Apr-2013 ken

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
MFC after: 2 weeks


# 224086 16-Jul-2011 zack

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


# 224082 16-Jul-2011 zack

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


# 224081 16-Jul-2011 zack

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


# 224080 16-Jul-2011 zack

Remove unnecessary thread pointer from VOPLOCK macros and current users.

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


# 223348 20-Jun-2011 rmacklem

Fix the new NFSv4 server so that it allows Access and Readlink
operations while traversing non-exported file systems. This is
required for some non-FreeBSD clients to do NFSv4 mounts. Found during
the recent NFSv4 interoperability Bakeathon.

MFC after: 2 weeks


# 222389 27-May-2011 rmacklem

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


# 217063 06-Jan-2011 rmacklem

Since the VFS_LOCK_GIANT() code in the experimental NFS
server is broken and the major file systems are now all
mpsafe, modify the server so that it will only export
mpsafe file systems. This was discussed on freebsd-fs@
and removes a fair bit of crufty code.

MFC after: 12 days


# 217023 05-Jan-2011 rmacklem

Modify the experimental NFS server so that it calls
vn_start_write() with a non-NULL vp. That way it will
find the correct mount point mp and use that mp for the
subsequent vn_finished_write() call. Also, it should fail
without crashing if the mount point is being forced dismounted
because vn_start_write() will set the mp NULL via VOP_GETWRITEMOUNT().

Reviewed by: kib
MFC after: 12 days


# 216897 02-Jan-2011 rmacklem

Modify the experimental NFSv4 server so that the lookup
ops return a locked vnode. This ensures that the associated mount
point will always be valid for the code that follows the operation.
Also add a couple of additional checks
for non-error to the other functions that create file objects.

MFC after: 2 weeks


# 216894 02-Jan-2011 rmacklem

Delete some cruft from the experimental NFS server that was
only used by the OpenBSD port for its pseudo-fs.

MFC after: 2 weeks


# 216893 02-Jan-2011 rmacklem

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


# 216700 25-Dec-2010 rmacklem

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


# 211951 28-Aug-2010 rmacklem

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


# 209120 13-Jun-2010 kib

In NFS clients, instead of inconsistently using #ifdef
DIAGNOSTIC and #ifndef DIAGNOSTIC for debug assertions, prefer
KASSERT(). Also change one #ifdef DIAGNOSTIC in the new nfs server.

Submitted by: Mikolaj Golub <to.my.trociny gmail com>
MFC after: 2 weeks


# 192781 25-May-2009 rmacklem

Fix the handling of NFSv4 Illegal Operation number to conform
to RFC3530 (the operation number in the reply must be set to
the value for OP_ILLEGAL). Also cleaned up some indentation.

Approved by: kib (mentor)


# 192121 14-May-2009 rmacklem

Apply changes to the experimental nfs server so that it uses the security
flavors as exported in FreeBSD-CURRENT. This allows it to use a
slightly modified mountd.c instead of a different utility.

Approved by: kib (mentor)


# 191940 09-May-2009 kan

Do not embed struct ucred into larger netcred parent structures.

Credential might need to hang around longer than its parent and be used
outside of mnt_explock scope controlling netcred lifetime. Use separate
reference-counted ucred allocated separately instead.

While there, extend mnt_explock coverage in vfs_stdexpcheck and clean-up
some unused declarations in new NFS code.

Reported by: John Hickey
PR: kern/133439
Reviewed by: dfr, kib


# 191783 04-May-2009 rmacklem

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)