Private read/write mapping can't be used to modify the mapped files, so
they will remain be immutable. Private read/write mappings are usually
used to load the data segment of executable files, rejecting them will
rendering immutable executable files to stop working.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: WHR <msl0000023508@gmail.com>
Closes#15344
With Linux v6.6.0 and GCC 12, when debug build is configured,
implicit conversion error is raised while converting
'enum <anonymous>' to 'boolean_t'. Use 'B_TRUE' instead of
'true' to fix the issue.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Pavel Snajdr <snajpa@snajpa.net>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes#15489
There is no sense to have separate implementations for FreeBSD and
Linux. Make Linux code shared as more functional and just register
FreeBSD-specific prune callback with arc_add_prune_callback() API.
Aside of code cleanup this should fix excessive pruning on FreeBSD:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=274698
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Johnston <markj@FreeBSD.org>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15456
In Linux commit 560e20e4bf6484a0c12f9f3c7a1aa55056948e1e, the
fsync_bdev() function was removed in favor of sync_blockdev() to do
(roughly) the same thing, given the same input. This change
conditionally attempts to call sync_blockdev() if fsync_bdev() isn't
discovered during configure.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15263
In commit 0d72b92883c651a11059d93335f33d65c6eb653b, a new u32 argument
for the request_mask was added to generic_fillattr. This is the same
request_mask for statx that's present in the most recent API implemented
by zpl_getattr_impl. This commit conditionally adds it to the
zpl_generic_fillattr(...) macro, as well as the zfs_getattr_fast(...)
implementation, when configure determines it's present in the kernel's
generic_fillattr(...).
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15263
In Linux commit 13bc24457850583a2e7203ded05b7209ab4bc5ef, direct access
to the i_ctime member of struct inode was removed. The new approach is
to use accessor methods that exclusively handle passing the timestamp
around by value. This change adds new tests for each of these functions
and introduces zpl_* equivalents in include/os/linux/zfs/sys/zpl.h. In
where the inode_get/set_ctime*() functions exist, these zpl_* calls will
be mapped to the new functions. On older kernels, these macros just wrap
direct-access calls. The code that operated on an address of ip->i_ctime
to call ZFS_TIME_DECODE() now will take a local copy using
zpl_inode_get_ctime(), and then pass the address of the local copy when
performing the ZFS_TIME_DECODE() call, in all cases, rather than
directly accessing the member.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15263Closes#15257
This reverts commit aefb6a2bd6.
aefb6a2bd temporally disabled blk-mq until we could fix a fix for
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#15439
This fix removes a dubious optimization in zfs_uiomove_bvec_rq()
that saved the iterator contents of a rq_for_each_segment(). This
optimization allowed restoring the "saved state" from a previous
rq_for_each_segment() call on the same uio so that you wouldn't
need to iterate though each bvec on every zfs_uiomove_bvec_rq() call.
However, if the kernel is manipulating the requests/bios/bvecs under
the covers between zfs_uiomove_bvec_rq() calls, then it could result
in corruption from using the "saved state". This optimization
results in an unbootable system after installing an OS on a zvol
with blk-mq enabled.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#15351
Variable 'uma_align_cache' has not been used since commit "FreeBSD: Use
a hash table for taskqid lookups" (3933305ea). Moreover, it is soon
going to become private to FreeBSD's UMA in 15.0-CURRENT (main),
14.0-STABLE (stable/14) and 13.2-STABLE (stable/13). Should accessing
this information become necessary again, one will have to use the new
accessors for recent versions.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olivier Certner <olce.freebsd@certner.fr>
Closes#15416
- Group tqent_task and tqent_timeout_task into a union. They are
never used same time. This shrinks taskq_ent_t from 192 to 160 bytes.
- Remove tqent_registered. Use tqent_id != 0 instead.
- Remove tqent_cancelled. Use taskqueue pending counter instead.
- Change tqent_type into uint_t. We don't need to pack it any more.
- Change tqent_rc into uint_t, matching refcount(9).
- Take shared locks in taskq_lookup().
- Call proper taskqueue_drain_timeout() for TIMEOUT_TASK in
taskq_cancel_id() and taskq_wait_id().
- Switch from CK_LIST to regular LIST.
Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mateusz Guzik <mjguzik@gmail.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15356
Right now, zpl_ioctl_ficlone and zpl_ioctl_ficlonerange do not call
put on the src fd if the source and destination are on two different
devices. This leaves the source file held open in this case.
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Daniel Berlin <dberlin@dberlin.org>
Closes#15386
There was a report of zvol data loss (#15351) after enabling blk-mq on a
zvol backed with 16k physical block sized disks. Out of an abundance of
caution, do not allow the user to enable blk-mq until we can look into
the issue.
Note that blk-mq was not enabled by default on zvols. It was always
opt-in via the zvol_use_blk_mq module parameter.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Addresses: #15351Closes#15378
This includes random small tweaks, primarily a build fixes, required
when ZFS is built as part of FreeBSD base.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15368
Before this change ZFS created threads for 50% of CPUs for each top-
level vdev. Plus it created the same number of threads for embedded
log groups (that have only one metaslab and don't need any preload).
As result, on system with 80 CPUs and pool of 60 vdevs this resulted
in 4800 metaslab preload threads, that is absolutely insane.
This patch changes the preload threads to 50% of CPUs in one taskq
per pool, so on the mentioned system it will be only 40 threads.
Among other things this fixes zdb on the mentioned system and pool
on FreeBSD, that failed to create so many threads in one process.
Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15319
Added in ab26409db7 ("Linux 3.1 compat, super_block->s_shrink"), with
the only consumer which needed the count getting retired in 066e825221
("Linux compat: Minimum kernel version 3.10").
The counter gets in the way of not maintaining the list to begin with.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes#15274
When register_sysctl_table() is unavailable we fail to properly
unregister sysctl entries under "kernel/spl".
This leads to errors like the following when spl is unloaded/reloaded,
making impossible to properly reload the spl module:
[ 746.995704] sysctl duplicate entry: /kernel/spl/kmem/slab_kvmem_total
Fix by cleaning up all the sub-entries inside "kernel/spl" when the
spl module is unloaded.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Closes#15239
If we fail to create a proc entry in spl_proc_init() we may end up
calling unregister_sysctl_table() twice: one in the failure path of
spl_proc_init() and another time during spl_proc_fini().
Avoid the double call to unregister_sysctl_table() and while at it
refactor the code a bit to reduce code duplication.
This was accidentally introduced when the spl code was
updated for Linux 6.5 compatibility.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Closes#15234Closes#15235
Using the filemap_splice_read function for the splice_read handler was
leading to occasional data corruption under certain circumstances. Favor
using copy_splice_read instead, which does not demonstrate the same
erroneous behavior under the tested failure cases.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15164
The generic_file_splice_read function was removed in Linux 6.5 in favor
of filemap_splice_read. Add an autoconf test for filemap_splice_read and
use it if it is found as the handler for .splice_read in the
file_operations struct. Additionally, ITER_PIPE was removed in 6.5. This
change removes the ITER_* macros that OpenZFS doesn't use from being
tested in config/kernel-vfs-iov_iter.m4. The removal of ITER_PIPE was
causing the test to fail, which also affected the code responsible for
setting the .splice_read handler, above. That behavior caused run-time
panics on Linux 6.5.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15155
Additionally, the .child element of ctl_table has been removed in 6.5.
This change adds a new test for the pre-6.5 register_sysctl_table()
function, and uses the old code in that case. If it isn't found, then
the parentage entries in the tables are removed, and the register_sysctl
call is provided the paths of "kernel/spl", "kernel/spl/kmem", and
"kernel/spl/kstat" directly, to populate each subdirectory over three
calls, as is the new API.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15138
This reverts commit b35374fd64 as there
are error messages when loading the SPL module. Errors seemed to be tied
to duplicate a duplicate entry.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes#15134
An iov_iter_type() function to access the "type" member of the struct
iov_iter was added at one point. Move the conditional logic to decide
which method to use for accessing it into a macro and simplify the
zpl_uio_init code.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15100
The iov_iter->iov member is now iov_iter->__iov and must be accessed via
the accessor function iter_iov(). Create a wrapper that is conditionally
compiled to use the access method appropriate for the target kernel
version.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15100
Multiple changes to the blkdev API were introduced in Linux 6.5. This
includes passing (void* holder) to blkdev_put, adding a new
blk_holder_ops* arg to blkdev_get_by_path, adding a new blk_mode_t type
that replaces uses of fmode_t, and removing an argument from the release
handler on block_device_operations that we weren't using. The open
function definition has also changed to take gendisk* and blk_mode_t, so
update it accordingly, too.
Implement local wrappers for blkdev_get_by_path() and
vdev_blkdev_put() so that the in-line calls are cleaner, and place the
conditionally-compiled implementation details inside of both of these
local wrappers. Both calls are exclusively used within vdev_disk.c, at
this time.
Add blk_mode_is_open_write() to test FMODE_WRITE / BLK_OPEN_WRITE
The wrapper function is now used for testing using the appropriate
method for the kernel, whether the open mode is writable or not.
Emphasize fmode_t arg in zvol_release is not used
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15099
Additionally, the .child element of ctl_table has been removed in 6.5.
This change adds a new test for the pre-6.5 register_sysctl_table()
function, and uses the old code in that case. If it isn't found, then
the parentage entries in the tables are removed, and the register_sysctl
call is provided the paths of "kernel/spl", "kernel/spl/kmem", and
"kernel/spl/kstat" directly, to populate each subdirectory over three
calls, as is the new API.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#15098
In 019dea0a5 we removed the conversion from EAGAIN->EXDEV inside
zfs_clone_range(), but forgot to add a test for EAGAIN to the
copy_file_range() entry points to trigger fallback to a content copy.
This commit fixes that.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#15170Closes#15172
Return the more descriptive error codes instead of `EXDEV` when
the parameters don't match the requirements of the clone function.
Updated the comments in `brt.c` accordingly.
The first three errors are just invalid parameters, which zfs can
not handle.
The fourth error indicates that the block which should be cloned
is created and cloned or modified in the same transaction
group (`txg`).
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <rob.norris@klarasystems.com>
Signed-off-by: Kay Pedersen <mail@mkwg.de>
Closes#15148
If looking up a snapdir inode failed, hold pool config – hold the
snapshot – get its creation property – release it – release it,
then use that as the [amc]time in the allocated inode. If that
fails then fall back to current time. No performance impact since
this is only done when allocating a new snapdir inode.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#15110Closes#15117
Before Linux 5.3, the filesystem's copy_file_range handler had to signal
back to the kernel that we can't fulfill the request and it should
fallback to a content copy. This is done by returning -EOPNOTSUPP.
This commit converts the EXDEV return from zfs_clone_range to
EOPNOTSUPP, to force the kernel to fallback for all the valid reasons it
might be unable to clone. Without it the copy_file_range() syscall will
return EXDEV to userspace, breaking its semantics.
Add test for copy_file_range fallbacks. copy_file_range should always
fallback to a content copy whenever ZFS can't service the request with
cloning.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#15131
Return the more descriptive EOPNOTSUPP instead of EXDEV when the
storage pool doesn't support block cloning.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <rob.norris@klarasystems.com>
Signed-off-by: Kay Pedersen <mail@mkwg.de>
Closes#15097
Redhat have backported copy_file_range and clone_file_range to the EL7
kernel using an "extended file operations" wrapper structure. This
connects all that up to let cloning work there too.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes#15050
Prior to Linux 4.5, the FICLONE etc ioctls were specific to BTRFS, and
were implemented as regular filesystem-specific ioctls. This implements
those ioctls directly in OpenZFS, allowing cloning to work on older
kernels.
There's no need to gate these behind version checks; on later kernels
Linux will simply never deliver these ioctls, instead calling the
approprate VFS op.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes#15050
This implements the Linux VFS ops required to service the file
copy/clone APIs:
.copy_file_range (4.5+)
.clone_file_range (4.5-4.19)
.dedupe_file_range (4.5-4.19)
.remap_file_range (4.20+)
Note that dedupe_file_range() and remap_file_range(REMAP_FILE_DEDUP) are
hooked up here, but are not implemented yet.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes#15050
Starting approximately from version 1302506 vn_lock_pair() grown two
additional arguments following head. There is a one week hole, but
that is closet reference point we have.
Reviewed-by: Mateusz Guzik <mjguzik@gmail.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15047
The default timeout for ZVOL opens may not be sufficient for all cases,
so we should enable the value to be more easily tuned to account for
systems where the default value is insufficient.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Prakash Surya <prakash.surya@delphix.com>
Closes#15023
It's been observed that in certain workloads (zvol-related being a
big one), ZFS will end up spending a large amount of time spinning
up taskqs only to tear them down again almost immediately, then
spin them up again...
I noticed this when I looked at what my mostly-idle system was doing
and wondered how on earth taskq creation/destroy was a bunch of time...
So I added a configurable delay to avoid it tearing down tasks the
first time it notices them idle, and the total number of threads at
steady state went up, but the amount of time being burned just
tearing down/turning up new ones almost vanished.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#14938
It was a vdev level read cache, designed to aggregate many small
reads by speculatively issuing bigger reads instead and caching
the result. But since it has almost no idea about what is going
on with exception of ZIO_FLAG_DONT_CACHE flag set by higher layers,
it was found to make more harm than good, for which reason it was
disabled for the past 12 years. These days we have much better
instruments to enlarge the I/Os, such as speculative and prescient
prefetches, I/O scheduler, I/O aggregation etc.
Besides just the dead code removal this removes one extra mutex
lock/unlock per write inside vdev_cache_write(), not otherwise
disabled and trying to do some work.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#14953
... instead of list_head() + list_remove(). On FreeBSD the list
functions are not inlined, so in addition to more compact code
this also saves another function call.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#14955
When a kmem cache is exhausted and needs to be expanded a new
slab is allocated. KM_SLEEP callers can block and wait for the
allocation, but KM_NOSLEEP callers were incorrectly allowed to
block as well.
Resolve this by attempting an emergency allocation as a best
effort. This may fail but that's fine since any KM_NOSLEEP
consumer is required to handle an allocation failure.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Adam Moss <c@yotes.com>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
There's no particular reason this function should be kernel-only, and I
want to use it (indirectly) from zdb. I've moved it to zfs_znode.c
because libzpool does not compile in zfs_vfsops.c, and this at least
matches the header its imported from.
Sponsored-By: Klara, Inc.
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: WHR <msl0000023508@gmail.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#14642
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes#14891
Protect zvol_cdev_read with zv_suspend_lock to prevent concurrent
release of the dnode, avoiding panic when a snapshot is rolled back
in parallel during ongoing zvol read operation.
Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#14839
It became illegal to not have them as of
5f6df177758b9dff88e4b6069aeb2359e8b0c493 ("vfs: validate that vop
vectors provide all or none fplookup vops") upstream.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes#14788
Not complete, but already shaves on some locking.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Sponsored by: Rubicon Communications, LLC ("Netgate")
Closes#14723
API contract requires VOPs to handle EXDEV internally, worst case by
falling back to the generic copy routine. This broke with the recent
changes.
While here whack custom loop to lock 2 vnodes with vn_lock_pair, which
provides the same functionality internally. write start/finish around
it plays no role so got eliminated.
One difference is that vn_lock_pair always takes an exclusive lock on
both vnodes. I did not patch around it because current code takes an
exclusive lock on the target vnode. zfs supports shared-locking for
writes, so this serializes different calls to the routine as is, despite
range locking inside. At the same time you may notice the source vnode
can get some traffic if only shared-locked, thus once more this goes
the safer route of exclusive-locking. Note this should be patched to
use shared-locking for both once the feature is considered stable.
Technically the switch to vn_lock_pair should be a separate change, but
it would only introduce churn immediately whacked by the rest of the
patch.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Sponsored by: Rubicon Communications, LLC ("Netgate")
Closes#14723
