Fix a misreport in 'zdb -d' where it falsely marked
BRT objects as leaked.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Yuxin Wang <yuxinwang9999@gmail.com>
Closes#15882
Similar to deduplication, the size of data duplicated by block cloning
should not be included in the slop space calculation.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Yuxin Wang <yuxinwang9999@gmail.com>
Closes#15874
Reviewed-by: John Wren Kennedy <john.kennedy@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Kevin Greene <kevin.greene@delphix.com>
Closes#15868
Fixes a small inaccuracy in the description of snapshot
atomicity
zfs-snapshot(8) appears to contain a small error. The existing
version reads "Snapshots are taken atomically, so that all
snapshots correspond to the same moment in time." Per
zfs_main.c, which in do_snapshot() simply loops over argv, this
does not appear to be correct when multiple snapshots are
specified explicitly on the command line. I believe the intent
of the man page was to say that *recursive* snapshots are all
created atomically.
This proposed change fixes that error. Because the existing
statement may confuse some readers anyway, the commit also also
adds a small amount of general explanatory information that may
be helpful.
The change also adds an introductory sentence that summarizes
what 'zfs snapshot' does in the first place. In that sentence,
the text "different datasets" is intended to indicate that
(again per the code) the same dataset cannot be specified
multiple times on the command line.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Shawn Bayern <sbayern@law.fsu.edu>
Closes#15857
Because "filesystem" and "volume" are just too long!
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#15864
Slow disk response times can be indicative of a failing drive. ZFS
currently tracks slow I/Os (slower than zio_slow_io_ms) and generates
events (ereport.fs.zfs.delay). However, no action is taken by ZED,
like is done for checksum or I/O errors. This change adds slow disk
diagnosis to ZED which is opt-in using new VDEV properties:
VDEV_PROP_SLOW_IO_N
VDEV_PROP_SLOW_IO_T
If multiple VDEVs in a pool are undergoing slow I/Os, then it skips
the zpool_vdev_degrade().
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Rob Wing <rob.wing@klarasystems.com>
Signed-off-by: Don Brady <don.brady@klarasystems.com>
Closes#15469
CVE-2020-24370 is a security vulnerability in lua. Although the CVE
description in CVE-2020-24370 said that this CVE only affected lua
5.4.0, according to lua this CVE actually existed since lua 5.2. The
root cause of this CVE is the negation overflow that occurs when you
try to take the negative of 0x80000000. Thus, this CVE also exists in
openzfs. Try to backport the fix to the lua in openzfs since the
original fix is for 5.4 and several functions have been changed.
https://github.com/advisories/GHSA-gfr4-c37g-mm3vhttps://nvd.nist.gov/vuln/detail/CVE-2020-24370https://www.lua.org/bugs.html#5.4.0-11https://github.com/lua/lua/commit/a585eae6e7ada1ca9271607a4f48dfb1786
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: ChenHao Lu <18302010006@fudan.edu.cn>
Closes#15847
When very large pools are present, it can be laborious to find
reasons for why a pool is degraded and/or where an unhealthy vdev
is. This option filters out vdevs that are ONLINE and with no errors
to make it easier to see where the issues are. Root and parents of
unhealthy vdevs will always be printed.
Testing:
ZFS errors and drive failures for multiple vdevs were simulated with
zinject.
Sample vdev listings with '-e' option
- All vdevs healthy
NAME STATE READ WRITE CKSUM
iron5 ONLINE 0 0 0
- ZFS errors
NAME STATE READ WRITE CKSUM
iron5 ONLINE 0 0 0
raidz2-5 ONLINE 1 0 0
L23 ONLINE 1 0 0
L24 ONLINE 1 0 0
L37 ONLINE 1 0 0
- Vdev faulted
NAME STATE READ WRITE CKSUM
iron5 DEGRADED 0 0 0
raidz2-6 DEGRADED 0 0 0
L67 FAULTED 0 0 0 too many errors
- Vdev faults and data errors
NAME STATE READ WRITE CKSUM
iron5 DEGRADED 0 0 0
raidz2-1 DEGRADED 0 0 0
L2 FAULTED 0 0 0 too many errors
raidz2-5 ONLINE 1 0 0
L23 ONLINE 1 0 0
L24 ONLINE 1 0 0
L37 ONLINE 1 0 0
raidz2-6 DEGRADED 0 0 0
L67 FAULTED 0 0 0 too many errors
- Vdev missing
NAME STATE READ WRITE CKSUM
iron5 DEGRADED 0 0 0
raidz2-6 DEGRADED 0 0 0
L67 UNAVAIL 3 1 0
- Slow devices when -s provided with -e
NAME STATE READ WRITE CKSUM SLOW
iron5 DEGRADED 0 0 0 -
raidz2-5 DEGRADED 0 0 0 -
L10 FAULTED 0 0 0 0 external device fault
L51 ONLINE 0 0 0 14
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Cameron Harr <harr1@llnl.gov>
Closes#15769
On Linux the ioctl_ficlonerange() and ioctl_ficlone() system calls
are expected to either fully clone the specified range or return an
error. The range may be for an entire file. While internally ZFS
supports cloning partial ranges there's no way to return the length
cloned to the caller so we need to make this all or nothing.
As part of this change support for the REMAP_FILE_CAN_SHORTEN flag
has been added. When REMAP_FILE_CAN_SHORTEN is set zfs_clone_range()
will return a shortened range when encountering pending dirty records.
When it's clear zfs_clone_range() will block and wait for the records
to be written out allowing the blocks to be cloned.
Furthermore, the file range lock is held over the region being cloned
to prevent it from being modified while cloning. This doesn't quite
provide an atomic semantics since if an error is encountered only a
portion of the range may be cloned. This will be converted to an
error if REMAP_FILE_CAN_SHORTEN was not provided and returned to the
caller. However, the destination file range is left in an undefined
state.
A test case has been added which exercises this functionality by
verifying that `cp --reflink=never|auto|always` works correctly.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#15728Closes#15842
Step 1 in trying to slowly rip the zdb functions out of zdb.c
to allow people to play with more flexible things to leverage
zdb's functionality.
No promises on any functions or structs being stable, now or probably
in general unless someone builds a more polished abstraction, the
goal at the moment is to slowly untangle the global state usage
in zdb...
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#15804
On Linux, ZFS uses blkdev_issue_discard in vdev_disk_io_trim to issue
trim command which is synchronous.
This commit updates vdev_disk_io_trim to use __blkdev_issue_discard,
which is asynchronous. Unfortunately there isn't any asynchronous
version for blkdev_issue_secure_erase, so performance of secure trim
will still suffer.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes#15843
struct mnt_idmap no longer has a struct user_namespace within it. Work
around this by creating a temporary with the copy of the map we need
taken from the idmap.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Youzhong Yang <yyang@mathworks.com>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15805
The name inode_permission is now defined in the kernel. Rename ours to
test_permission, in line with most of our other tests.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15805
MAX_ORDER has been renamed to MAX_PAGE_ORDER. Rather than just
redefining it, instead define our own name and set it consistently from
the start.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15805
Linux has removed strlcpy in favour of strscpy. This implements a
fallback implementation of strlcpy for this case.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15805
blkdev_get_by_path() and blkdev_put() have been replaced by
bdev_open_by_path() and bdev_release(), which return a "handle" object
with the bdev object itself inside.
This adds detection for the new functions, and macros to handle the old
and new forms consistently.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15805
The kernel is now being compiled with -Wmissing-prototypes. Most of our
test stub functions had no prototype, and failed to compile. Since they
don't need to be visible anywhere else, just make them all static.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15805
Update the META file to reflect compatibility with the 6.7 kernel.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#15833
During device removal stress tests, we noticed that we were tripping
the assertion that mg_initialized was true. After investigation, it was
determined that the mg in question was the embedded log metaslab
group for a newly added vdev; the normal mg had been initialized (by
metaslab_sync_reassess, via vdev_sync_done). However, because the spa
config alloc lock is not held as writer across both calls to
metaslab_sync_reassess, it is possible for an allocation to happen
between the two metaslab_groups being initialized. Because the metaslab
code doesn't check the group in question, just the vdev's main mg, it
is possible to get past the initial check in vdev_allocatable and
later fail due to the assertion.
We simply remove the assertions. We could also consider locking the
ALLOC lock around the reassess calls in vdev_sync_done, but that risks
deadlocks. We could check the actual target mg in vdev_allocatable,
but that risks racing with a passivation that comes in after that
check but before the assertion. We still won't be able to actually
allocate from the metaslab group if no metaslabs are ready, so this
change shouldn't break anything.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#15818
Since we're looking for a single new-line character in the haystack,
it's better (and slightly more efficient) to use strchr() instead of
strstr().
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: rilysh <nightquick@proton.me>
Closes#15798
zpool-iostat.8: Updated time(2) -> time(1) to align to manual page
zpool-list.8: Updated time(2) -> time(1) to align to manual page
zpool-status.8: Updated time(2) -> time(1) to align to manual page
zpool-wait.8: Update time(2) -> time(1) to align to manual page
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Christopher Davidson <christopher.davidson@gmail.com>
Closes#15823
The zdb_args_pos test may take slightly longer than 600 seconds to run
on some of the CI builders. To prevent this from causing failures allow
up to 1200 seconds for tests in this group.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#15826
Removed the list_size struct member as it was only used in a single
assertion, as mentioned in PR #15478.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: MigeljanImeri <imerimigel@gmail.com>
Closes#15812
list, status and iostat all display the -T timestamp before the header,
but wait showed it after. Make it be like the others.
Reported-by: Kyle Evans <kevans@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#15825
If devid or physpath for a vdev changes between imports, ensure it is
updated to the new value.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#15816
GitHub Actions is transitioning from Node 16 to Node 20.
So we need to update these:
- actions/checkout@v3 -> v4
- actions/download-artifact@v3 -> v4
- actions/upload-artifact@v3 -> v4 and some minor changes
Update also the documentation of the testings workflow.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Andrew Innes <andrew.c12@gmail.com>
Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de>
Closes#15820
The LLVM/Clang developers pointed out that using the CPP to detect use
of functions that our QA policies prohibit risks invoking undefined
behavior. To resolve this, we configure CodeQL to detect forbidden
function usage.
Note that cpp in the context of CodeQL refers to C/C++, rather than the
C PreProcessor, which C++ also uses. It really should have been written
cxx, but that ship sailed a long time ago. This misuse of the term cpp
is retained in the CodeQL configuration for consistency with upstream
CodeQL.
As a side benefit, verbose make no longer is a wall of text showing a
bunch of CPP macros, which can make debugging slightly easier.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#15819Closes#14134
The Github Action Runner got some new hardware metrics. We should use
the provided and empty disk which is pre-mounted at /mnt now.
Disk1: 89GiB -> rootfs + bootfs with ~80MB/s -> don't care
Disk2: 64GiB -> /mnt with 420MB/s -> new testing ssd
This commit will mount the new disk to /var/tmp and provide hopefully
some speedups within our testings.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Andrew Innes <andrew.c12@gmail.com>
Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de>
Closes#15811
Descriptor leak can be easily reproduced by doing:
# zpool import tank
# sysctl kern.openfiles
# zpool export tank; zpool import tank
# sysctl kern.openfiles
We were leaking four file descriptors on every import.
Similar leak most likely existed when using file-based VDEVs.
External-issue: https://reviews.freebsd.org/D43529
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Pawel Jakub Dawidek <pawel@dawidek.net>
Closes#15630
If block cloning is disabled by default then enable it when running
the bclone tests. Follow up to #15529.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#15796
musl libc has deprecated LFS64 aliases, so bootstrapping FreeBSD tools
under musl distros has been failing with stat64 errors.
Apply the aliases under non-glibc Linux to fix this problem.
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Val Packett <val@packett.cool>
Closes#15780
Compiling on arm64 freebsd-13.2 and arm64 almalinux-8 brings currently
this error:
```
CC tests/zfs-tests/cmd/clonefile.o
tests/zfs-tests/cmd/clonefile.c:166:43: error: result of comparison of \
constant -1 with expression of type 'char' is always true \
[-Werror,-Wtautological-constant-out-of-range-compare]
while ((c = getopt(argc, argv, "crfdq")) != -1) {
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~
1 error generated.
gmake[2]: *** [Makefile:8675: tests/zfs-tests/cmd/clonefile.o] Error 1
```
Fix: use correct variable type `int`.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <robn@despairlabs.com>
Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de>
Closes#15783
Switch from cv_wait() to cv_wait_idle() in vdev_autotrim_wait_kick(),
which should mitigate the high load average while waiting.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: jxdking <lostking2008@hotmail.com>
Closes#15781
If the destination file is mmaped and the mmaped region was already
read, so it is cached, we need to update mmaped pages after successful
clone using update_pages().
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Pointed out by: Ka Ho Ng <khng@freebsd.org>
Signed-off-by: Pawel Jakub Dawidek <pawel@dawidek.net>
Closes#15772
In db4fc559c I messed up and changed this bit of code to set the inode
atime to an uninitialised value, when actually it was just supposed to
loading the atime from the inode to be stored in the SA. This changes it
to what it should have been.
Ensure times change by the right amount Previously, we only checked
if the times changed at all, which missed a bug where the atime was
being set to an undefined value.
Now ensure the times change by two seconds (or thereabouts), ensuring
we catch cases where we set the time to something bonkers
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/Closes#15762Closes#15773
When building (s)rpm files through the Makefile, a directory structure
is created in /tmp to hold the various files.
In case the user running the command has overridden some of the RPM path
settings through their user profile (for example in `~/.rpmmacros`),
these paths do not line up with the configuration, and the build fails.
Make sure all paths used are properly defined.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ralf Ertzinger <ralf@skytale.net>
Closes#15756
On Linux x86_64, kmem cache can have size up to 4M,
however increasing spl_kmem_cache_slab_limit can lead
to crash due to the size check inconsistency.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes#15757
If the AUX vdev is added using UUID, importing the pool falls back AUX
vdev to open it with disk name instead of UUID due to the absence of
path information for AUX vdevs. Since AUX label now have path
information, this PR adds path handling for it in `label_path`.
Reviewed-by: Umer Saleem <usaleem@ixsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#15737
Pool import logic uses vdev paths, so it makes sense to add path
information on AUX vdev as well.
Reviewed-by: Umer Saleem <usaleem@ixsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#15737
When spare or l2cache (aux) vdev is added during pool creation,
spa->spa_uberblock is not dumped until that point. Subsequently,
the aux label is never synchronized after its initial creation,
resulting in the uberblock label remaining undumped. The uberblock
is crucial for lib_blkid in identifying the ZFS partition type. To
address this issue, we now ensure sync of the uberblock label once
if it's not dumped initially.
Reviewed-by: Umer Saleem <usaleem@ixsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#15737
zdb -R has a minor flaw in which it will not always print the full
output of a decompressed block. Oops.
While I was in there, I also reworked the logic so it won't try
ZLE unless everything else fails, which will hopefully avoid the
problem ZDB_NO_ZLE was intended to mitigate of reporting a lot of
false positives of ZLE compressed blocks...
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#15723
For block cloning, if we mmap the cloned file and write from the
map into the file, it triggers a panic in dbuf_redirty() on Linux.
The same scenario causes data corruption on FreeBSD. Both these
issues are fixed under PR#15656 and PR#15665.
It would be good to add a test for this scenario in ZTS. The test
program and issue was produced by @robn.
Reviewed-by: Pawel Jakub Dawidek <pawel@dawidek.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes#15717
Drop the no_memory() call from zpool_in_use() when reading the
label fails and instead return the error to the caller. This
prevents a misleading "internal error: out of memory" error
when the label can't be read. This will result in is_spare()
returning B_FALSE instead of aborting, which is already safely
handled.
Furthermore, on Linux it's possible for EREMOTEIO to returned
by an NVMe device if the device has been low-level formatted
and not rescanned. In this case we want to fallback to the
legacy scanning method and read any of the labels we can.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #13538Closes#15747
This change provides rpm spec macros to sign the zfs and spl kmods as
the final step after the %install scriptlet. This is needed since the
find-debuginfo.sh script strips out debug symbols plus signatures.
Kernel module signing only occurs when the required files are present
as typically required in the Linux source tree:
- certs/signing_key.pem
- certs/signing_key.x509
The method for overriding the default __spec_install_post macro is
inspired by (and largely copied from) the Fedora kernel.spec.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Benjamin Sherman <benjamin@holyarmy.org>
Closes#15744
For FreeBSD sysctls, we don't want the extra newline, since the
sysctl(8) utility will format strings appropriately.
Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reported-by: Peter Holm <pho@FreeBSD.org>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Closes#15719
sbuf_cpy() resets the sbuf state, which is wrong for sbufs allocated by
sbuf_new_for_sysctl(). In particular, this code triggers an assertion
failure in sbuf_clear().
Simplify by just using sysctl_handle_string() for both reading and
setting the tunable.
Fixes: 6930ecbb7 ("spa: make read/write queues configurable")
Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reported-by: Peter Holm <pho@FreeBSD.org>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Closes#15719
