4214 Commits

Author SHA1 Message Date
Doug Moore
f9f4c60aa7 Including <sys/tmpfs.h> into non-kernel software leads to a
compilation error because, without _KERNEL defined, the macro
TMPFS_VALIDATE_DIR is invoked, but never defined. User-level software
that includes sys/tmpfs.h must define _KERNEL to make the definition
of TMPFS_VALIDATE_DIR visible.

This change puts all the inline functions that, directly or
indirectly, invoke MPASS into the scope of the _KERNEL block, allowing
many user-space includers of <sys/tmpfs.h> to stop defining _KERNEL.

Reviewed by:	alc, kib
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D22874
2019-12-19 16:39:52 +00:00
Mateusz Guzik
6fa079fc3f vfs: flatten vop vectors
This eliminates the following loop from all VOP calls:

while(vop != NULL && \
    vop->vop_spare2 == NULL && vop->vop_bypass == NULL)
        vop = vop->vop_default;

Reviewed by:	jeff
Tesetd by:	pho
Differential Revision:	https://reviews.freebsd.org/D22738
2019-12-16 00:06:22 +00:00
Jeff Roberson
a808177864 Add a deferred free mechanism for freeing swap space that does not require
an exclusive object lock.

Previously swap space was freed on a best effort basis when a page that
had valid swap was dirtied, thus invalidating the swap copy.  This may be
done inconsistently and requires the object lock which is not always
convenient.

Instead, track when swap space is present.  The first dirty is responsible
for deleting space or setting PGA_SWAP_FREE which will trigger background
scans to free the swap space.

Simplify the locking in vm_fault_dirty() now that we can reliably identify
the first dirty.

Discussed with:	alc, kib, markj
Differential Revision:	https://reviews.freebsd.org/D22654
2019-12-15 03:15:06 +00:00
Rick Macklem
f808cf7294 Silence some "might not be initialized" warnings for riscv64.
None of these case were actually using the variable(s) uninitialized, but
I figured that silencing the warnings via initializing them made sense.

Some of these predated r355677.
2019-12-13 21:38:08 +00:00
Rick Macklem
bf6ac05aa3 Add some more initializations to quiet riscv build.
The one case in nfs_copy_file_range() was a legitimate case, although
it would probably never occur in practice.
2019-12-13 01:34:25 +00:00
Rick Macklem
95bf2e523b Fix the build for MAC not defined and a couple of might not be initialized.
r355677 broke the build for the not MAC defined case and a couple of
might not be initialized warnings were generated for riscv. Others seem
to be erroneous.

Hopefully there won't be too many more build errors.

Pointy hat goes on me.
2019-12-13 00:45:14 +00:00
Rick Macklem
c057a37818 Add support for NFSv4.2 to the NFS client and server.
This patch adds support for NFSv4.2 (RFC-7862) and Extended Attributes
(RFC-8276) to the NFS client and server.
NFSv4.2 is comprised of several optional features that can be supported
in addition to NFSv4.1. This patch adds the following optional features:
   - posix_fadvise(POSIX_FADV_WILLNEED/POSIX_FADV_DONTNEED)
   - posix_fallocate()
   - intra server file range copying via the copy_file_range(2) syscall
     --> Avoiding data tranfer over the wire to/from the NFS client.
   - lseek(SEEK_DATA/SEEK_HOLE)
   - Extended attribute syscalls for "user" namespace attributes as defined
     by RFC-8276.

Although this patch is fairly large, it should not affect support for
the other versions of NFS. However it does add two new sysctls that allow
a sysadmin to limit which minor versions of NFSv4 a server supports, allowing
a sysadmin to disable NFSv4.2.

Unfortunately, when the NFS stats structure was last revised, it was assumed
that there would be no additional operations added beyond what was
specified in RFC-7862. However RFC-8276 did add additional operations,
forcing the NFS stats structure to revised again. It now has extra unused
entries in all arrays, so that future extensions to NFSv4.2 can be
accomodated without revising this structure again.

A future commit will update nfsstat(1) to report counts for the new NFSv4.2
specific operations/procedures.

This patch affects the internal interface between the nfscommon, nfscl and
nfsd modules and, as such, they all must be upgraded simultaneously.
I will do a version bump (although arguably not needed), due to this.

This code has survived a "make universe" but has not been built with a
recent GCC. If you encounter build problems, please email me.

Relnotes:	yes
2019-12-12 23:22:55 +00:00
Mateusz Guzik
c8b29d1212 vfs: locking primitives which elide ->v_vnlock and shared locking disablement
Both of these features are not needed by many consumers and result in avoidable
reads which in turn puts them on profiles due to cache-line ping ponging.

On top of that the current lockgmr entry point is slower than necessary
single-threaded. As an attempted clean up preparing for other changes,
provide new routines which don't support any of the aforementioned features.

With these patches in place vop_stdlock and vop_stdunlock disappear from
flamegraphs during -j 104 buildkernel.

Reviewed by:	jeff (previous version)
Tested by:	pho
Differential Revision:	https://reviews.freebsd.org/D22665
2019-12-11 23:11:21 +00:00
Mateusz Guzik
abd80ddb94 vfs: introduce v_irflag and make v_type smaller
The current vnode layout is not smp-friendly by having frequently read data
avoidably sharing cachelines with very frequently modified fields. In
particular v_iflag inspected for VI_DOOMED can be found in the same line with
v_usecount. Instead make it available in the same cacheline as the v_op, v_data
and v_type which all get read all the time.

v_type is avoidably 4 bytes while the necessary data will easily fit in 1.
Shrinking it frees up 3 bytes, 2 of which get used here to introduce a new
flag field with a new value: VIRF_DOOMED.

Reviewed by:	kib, jeff
Differential Revision:	https://reviews.freebsd.org/D22715
2019-12-08 21:30:04 +00:00
Rick Macklem
a95cd06e9a Delete an unused external declaration.
Since nfsv4_opflag is no longer used in nfs_clcomsubs.c, delete the
external declaration of it. Found during NFSv4.2 code merge.

MFC after:	2 weeks
2019-12-08 16:59:36 +00:00
Rick Macklem
8e1906f700 Fix kernel handling of a NFSERR_MINORVERSMISMATCH NFSv4 server reply.
When an NFSv4 server replies NFSERR_MINORVERSMISMATCH, it does not generate
a status result for the first operation in the compound. Without this
patch, this will result in a bogus EBADXDR error return.
Returning EBADXDR is relatively harmless, but a correct reply of
NFSERR_MINORVERSMISMATCH is needed by the pNFS client to select the correct
minor version to use for a File Layout DS now that there can be NFSv4.2
DS servers.

mount_nfs.c still needs to be fixed for this, although how the mount fails
is only useful to help sysadmins isolate why a mount fails.

Found during testing of the NFSv4.2 client and server.

MFC after:	2 weeks
2019-12-08 00:06:00 +00:00
Rick Macklem
238da71f91 Add some definitions for NFSv4.2 which will be used by subsequent commits.
This is a preliminary commit of NFSv4.2 definitions that will be used by
subsequent commits which adds NFSv4.2 support to the NFS client and server.

There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
2019-12-07 23:13:51 +00:00
Rick Macklem
394dae30b1 Set the XATTRSUPPORT attribute bit for NFSv4.2, always cleared for now.
Since r355472 added code which clears the XATTRSUPPORT bit for non-NFSv4.2
mounts, it is now safe to set it.

There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
This commit completes updates to nfsproto.h required by the NFSv4.2.
2019-12-07 01:10:38 +00:00
Rick Macklem
2096ce0339 Add a couple of definitions for NFSv4.2 and update macros to use them.
This patch adds code to macros to clear attribute bits not supported
by NFSv4.2. For now, these bits are never set anyhow, but this prepares
the code for the addition of NFSv4.2 support in a future commit.

There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
2019-12-06 23:51:11 +00:00
Rick Macklem
8f9259a550 Add some definitions for NFSv4.2 which will be used by subsequent commits.
This is a preliminary commit of NFSv4.2 definitions that will be used by
subsequent commits which adds NFSv4.2 support to the NFS client and server.

There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
2019-12-06 01:53:02 +00:00
Mateusz Guzik
1e0006e49c nullfs: locklessly check for entries in null_hashget
During random sampling over poudriere -j 104 over 10% of calls returned NULL.
2019-12-05 13:41:22 +00:00
Konstantin Belousov
a51c8071a3 Stop using per-mount tmpfs zones.
Requested and reviewed by:	jeff
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D22643
2019-12-05 00:03:17 +00:00
Rick Macklem
348d9b567e Add some definitions for NFSv4.2 which will be used by subsequent commits.
This is a preliminary commit of NFSv4.2 definitions that will be used by
subsequent commits which adds NFSv4.2 support to the NFS client and server.

There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
2019-12-04 23:24:40 +00:00
Mateusz Guzik
ba08feecbf tmpfs: use proper macros for permission values in tmpfs_access
While here group them in one var to prevent overy long lines. Perhaps a
general macro of the same sort should be introduced.

Requested by:	kib
2019-12-01 00:34:49 +00:00
Kyle Evans
1b50b999f9 tty: implement TIOCNOTTY
Generally, it's preferred that an application fork/setsid if it doesn't want
to keep its controlling TTY, but it could be that a debugger is trying to
steal it instead -- so it would hook in, drop the controlling TTY, then do
some magic to set things up again. In this case, TIOCNOTTY is quite handy
and still respected by at least OpenBSD, NetBSD, and Linux as far as I can
tell.

I've dropped the note about obsoletion, as I intend to support TIOCNOTTY as
long as it doesn't impose a major burden.

Reviewed by:	bcr (manpages), kib
Differential Revision:	https://reviews.freebsd.org/D22572
2019-11-30 20:10:50 +00:00
Mateusz Guzik
a02cab334c devfs: introduce a per-dev lock to protect ->si_devsw
This allows bumping threadcount without taking the global devmtx lock.

In particular this eliminates contention on said lock while using bhyve
with multiple vms.

Reviewed by:	kib
Tested by:	markj
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22548
2019-11-30 16:46:19 +00:00
Mateusz Guzik
0f4b850e85 tmpfs: add fast path to tmpfs_access for common case lookup
VEXEC consists of vast majority of all calls and almost all targets have
at least 0111.
2019-11-30 16:41:47 +00:00
Konstantin Belousov
9698d99230 In nfs_lock(), recheck vp->v_data after lock before accessing it.
We might race with reclaim, and then this is no longer a nfs vnode, in
which case we do not need to handle deferred vnode_pager_setsize()
either.

Reported by:	rk@ronald.org
PR:	 242184
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2019-11-29 13:55:56 +00:00
Rick Macklem
e1cda5eea6 Fix two races while handling nfsuserd daemon start/stop.
A crash was reported where the nr_client field was NULL during an upcall
to the nfsuserd daemon. Since nr_client == NULL only occurs when the
nfsuserd daemon is being shut down, it appeared to be caused by a race
between doing an upcall and the daemon shutting down.
By inspection two races were identified:
1 - The nfsrv_nfsuserd variable is used to indicate whether or not the
    daemon is running. However it did not handle the intermediate phase
    where the daemon is starting or stopping.

    This was fixed by making nfsrv_nfsuserd tri-state and having the
    functions that are called during start/stop to obey the intermediate
    state.

2 - nfsrv_nfsuserd was checked to see that the daemon was running at
    the beginning of an upcall, but nothing prevented the daemon from
    being shut down while an upcall was still in progress.
    This race probably caused the crash.

    The patch fixes this by adding a count of upcalls in progress and
    having the shut down function delay until this count goes to zero
    before getting rid of nr_client and related data used by an upcall.

Tested by:	avg (Panzura QA)
Reported by:	avg
Reviewed by:	avg
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D22377
2019-11-28 23:34:23 +00:00
Konstantin Belousov
dbe257d253 tmpfs: resolve deadlock between rename and unmount.
Top-level kern_renameat() increases the writecount on the mount point,
which, together with tmpfs unmount suspending the mount, already
ensures that unmount cannot proceed while rename unlocks and relocks
all operated vnodes.

Remove vfs_busy() call from tmpfs_rename() which was done while
holding a vnode lock, creating the deadlock.  The only intent of the
busy operation seems to be the prevention of unmount, which is already
ensured.

Reported and tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-11-24 19:06:38 +00:00
Rick Macklem
14eff785e8 Fix the pNFS server's reporting of SpaceUsed (va_bytes).
The pNFS server currently reports SpaceUsed (va_bytes) for the metadata
file. This in not correct, since the metadata file is always empty and,
as such, va_bytes is just the allocation for the empty file.
This patch adds va_bytes to the list of attributes acquired from the
DS for a file, so that it includes the allocated data size and is updated
when the file is written.
For files created on a pNFS server before this patch is applied, the
va_bytes value is estimated by rounding va_size up to a multiple of
BLKDEV_IOSIZE. Once the file is written after this patch has been
applied to the metadata server, the va_bytes returned for the file
will be correct.

This patch only affects a pNFS metadata server.

Found during testing of the NFSv4.2 pNFS server for the Allocate operation.
(Not yet in head/current.)

MFC after:	2 weeks
2019-11-22 00:22:55 +00:00
Mateusz Guzik
1fccb43c39 vfs: change si_usecount management to count used vnodes
Currently si_usecount is effectively a sum of usecounts from all associated
vnodes. This is maintained by special-casing for VCHR every time usecount is
modified. Apart from complicating the code a little bit, it has a scalability
impact since it forces a read from a cacheline shared with said count.

There are no consumers of the feature in the ports tree. In head there are only
2: revoke and devfs_close. Both can get away with a weaker requirement than the
exact usecount, namely just the count of active vnodes. Changing the meaning to
the latter means we only need to modify it on 0<->1 transitions, avoiding the
check plenty of times (and entirely in something like vrefact).

Reviewed by:	kib, jeff
Tested by:	pho
Differential Revision:	https://reviews.freebsd.org/D22202
2019-11-20 12:05:59 +00:00
Jeff Roberson
639676877b Simplify anonymous memory handling with an OBJ_ANON flag. This eliminates
reudundant complicated checks and additional locking required only for
anonymous memory.  Introduce vm_object_allocate_anon() to create these
objects.  DEFAULT and SWAP objects now have the correct settings for
non-anonymous consumers and so individual consumers need not modify the
default flags to create super-pages and avoid ONEMAPPING/NOSPLIT.

Reviewed by:	alc, dougm, kib, markj
Tested by:	pho
Differential Revision:	https://reviews.freebsd.org/D22119
2019-11-19 23:19:43 +00:00
Jeff Roberson
67d0e29304 Replace OBJ_MIGHTBEDIRTY with a system using atomics. Remove the TMPFS_DIRTY
flag and use the same system.

This enables further fault locking improvements by allowing more faults to
proceed with a shared lock.

Reviewed by:	kib
Tested by:	pho
Differential Revision:	https://reviews.freebsd.org/D22116
2019-10-29 21:06:34 +00:00
Mateusz Guzik
2e310f6f72 pseudofs: hashed vncache
Vast majority of uses the cache are just checking if there is an entry
present on process exit (and evicting it if so). Both checking and
eviction process are very expensive and put the lock protecting it high
up on the profile during poudriere -j 104.

Convert the linked list into a hash. This allows to almost always avoid
taking the lock in the first place (and consequently almost removes it
from the profile). Note only one lock is preserved as a split did not
meaningfully impact contention.

Should the cache be used for something it will still run into contention
issues. The code needs a rewrite, but should someone want to tidy it up
further the following can be done:

1) per-chain locks (or at least an array)
2) hashing by something else than just pid

Sponsored by:	The FreeBSD Foundation
2019-10-22 22:52:53 +00:00
Konstantin Belousov
c6ba06d86c Fix interface between nfsclient and vnode pager.
Make the nfsclient always call vnode_pager_setsize() with the vnode
exclusively locked.  This ensures that page fault always can find the
backing page if the object size check succeeded.  Set VV_VMSIZEVNLOCK
flag on NFS nodes.

The main offender breaking the interface in nfsclient is
nfs_loadattrcache(), which is used whenever server responded with
updated attributes, which can happen on non-changing operations as
well.  Also, iod threads only have buffers locked (and even that is
LK_KERNPROC), but they still may call nfs_loadattrcache() on RPC
response.

Instead of immediately calling vnode_pager_setsize() if server
response indicated changed file size, but the vnode is not exclusively
locked, set a new node flag NVNSETSZSKIP.  When the vnode exclusively
locked, or when we can temporary upgrade the lock to exclusive, call
vnode_pager_setsize(), by providing the nfsclient VOP_LOCK() implementation.

Tested by:	pho
Discussed with:	rmacklem
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D21883
2019-10-22 16:17:38 +00:00
Jeff Roberson
0012f373e4 (4/6) Protect page valid with the busy lock.
Atomics are used for page busy and valid state when the shared busy is
held.  The details of the locking protocol and valid and dirty
synchronization are in the updated vm_page.h comments.

Reviewed by:    kib, markj
Tested by:      pho
Sponsored by:   Netflix, Intel
Differential Revision:        https://reviews.freebsd.org/D21594
2019-10-15 03:45:41 +00:00
Jeff Roberson
63e9755548 (1/6) Replace busy checks with acquires where it is trival to do so.
This is the first in a series of patches that promotes the page busy field
to a first class lock that no longer requires the object lock for
consistency.

Reviewed by:	kib, markj
Tested by:	pho
Sponsored by:	Netflix, Intel
Differential Revision:	https://reviews.freebsd.org/D21548
2019-10-15 03:35:11 +00:00
Mateusz Guzik
9c04e4c01e tmpfs: use MNTK_NOMSYNC
Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22009
2019-10-13 15:42:41 +00:00
Mateusz Guzik
48c426f226 pseudofs: use MNTK_NOMSYNC
Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22009
2019-10-13 15:42:25 +00:00
Mateusz Guzik
be4cd6912f nullfs: use MNTK_NOMSYNC
Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22009
2019-10-13 15:42:04 +00:00
Mateusz Guzik
4c9ba39aea devfs: use MNTK_NOMSYNC
Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D22009
2019-10-13 15:41:47 +00:00
Konstantin Belousov
e3fdd051f9 devfs_vptocnp(): correct the component name when node is not at top.
Node' cdp.si_name is the full path as provided by make_dev(9), it
should not be returned by VOP_VPTOCNP() when only the last component
is requested.  Use the dirent entry instead.

With this note, handling of VDIR and VCHR nodes only differs in
handling of root vnode, which simplifies and unifies the logic.

Reported by:	Li, Zhichao1 <Zhichao_Li1@Dell.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-10-11 18:41:24 +00:00
Konstantin Belousov
53fcc6c960 Plug the rest of undef behavior places that were missed in r337456.
There are three more places in msdosfs_fat.c which might shift one
into the sign bit.  While there, fix formatting of KASSERTs.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-10-11 18:37:02 +00:00
Doug Moore
2288078c5e Define macro VM_MAP_ENTRY_FOREACH for enumerating the entries in a vm_map.
In case the implementation ever changes from using a chain of next pointers,
then changing the macro definition will be necessary, but changing all the
files that iterate over vm_map entries will not.

Drop a counter in vm_object.c that would have an effect only if the
vm_map entry count was wrong.

Discussed with: alc
Reviewed by: markj
Tested by: pho (earlier version)
Differential Revision:	https://reviews.freebsd.org/D21882
2019-10-08 07:14:21 +00:00
Mateusz Guzik
d511f93e45 nfsclient: add root vnode caching
See r353150.

Sponsored by:   The FreeBSD Foundation
Differential Revision:  https://reviews.freebsd.org/D21646
2019-10-06 22:17:29 +00:00
Mateusz Guzik
7682d0be2b tmpfs: add root vnode caching
See r353150.

Sponsored by:   The FreeBSD Foundation
Differential Revision:  https://reviews.freebsd.org/D21646
2019-10-06 22:17:11 +00:00
Mateusz Guzik
559ac49d41 devfs: add root vnode caching
See r353150.

Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D21646
2019-10-06 22:16:55 +00:00
Mateusz Guzik
dfa8dae493 devfs: plug redundant bwillwrite avoidance
vn_write already checks for vnode type to see if bwillwrite should be called.

This effectively reverts r244643.

Reviewed by:	kib
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D21905
2019-10-05 17:44:33 +00:00
Konstantin Belousov
c5dac63c15 tmpfs_readdir(): unlock the locked node.
During readdir() we guarantee that the tn_dir.tn_parent does not go
away, but it might be replaced by a parallel rename.  Read tn_parent
only once, then use the cached value.

Reported and tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-10-03 19:55:05 +00:00
Konstantin Belousov
f7e69a6fa0 tmpfs_rename: style.
Reformat multi-line comments to follow style.
Also fix some typos.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2019-10-03 19:51:56 +00:00
Konstantin Belousov
d60ac9d561 Remove unnecessary vm/vm_page.h and vm/vm_pager.h includes from
tmpfs/tmpfs_vnodes.c.

Submitted by:	ota@j.email.ne.jp
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D21881
2019-10-03 08:25:09 +00:00
Rick Macklem
ee7201a725 Replace all mtx_assert() calls for n_mtx and ncl_iod_mutex with macros.
To be consistent with replacing the mtx_lock()/mtx_unlock() calls on
the NFS node mutex (n_mtx) and ncl_iod_mutex, this patch replaces
all mtx_assert() calls on these mutexes with macros as well.
This will simplify changing these locks to sx locks in a future commit.
However, this change may be delayed indefinitely, since it appears there
is a deadlock when vnode_pager_setsize() is called to shrink the size
and the NFS node lock is held.
There is no semantic change as a result of this commit.

Suggested by:	kib
MFC after:	1 week
2019-09-26 02:54:45 +00:00
Rick Macklem
b662b41e62 Replace all mtx_lock()/mtx_unlock() on the iod lock with macros.
Since the NFS node mutex needs to change to an sx lock so it can be held when
vnode_pager_setsize() is called and the iod lock is held when the NFS node lock
is acquired, the iod mutex will need to be changed to an sx lock as well.
To simply the future commit that changes both the NFS node lock and iod lock
to sx locks, this commit replaces all mtx_lock()/mtx_unlock() calls on the
iod lock with macros.
There is no semantic change as a result of this commit.

I don't know when the future commit will happen and be MFC'd, so I have
set the MFC on this commit to one week so that it can be MFC'd at the same
time.

Suggested by:	kib
MFC after:	1 week
2019-09-24 23:38:10 +00:00
Rick Macklem
5d85e12f44 Replace all mtx_lock()/mtx_unlock() on n_mtx with the macros.
For a long time, some places in the NFS code have locked/unlocked the
NFS node lock with the macros NFSLOCKNODE()/NFSUNLOCKNODE() whereas
others have simply used mtx_lock()/mtx_unlock().
Since the NFS node mutex needs to change to an sx lock so it can be held when
vnode_pager_setsize() is called, replace all occurrences of mtx_lock/mtx_unlock
with the macros to simply making the change to an sx lock in future commit.
There is no semantic change as a result of this commit.

I am not sure if the change to an sx lock will be MFC'd soon, so I put
an MFC of 1 week on this commit so that it could be MFC'd with that commit.

Suggested by:	kib
MFC after:	1 week
2019-09-24 01:58:54 +00:00