And add a note on /why/ ZEDLETs need to be owned by root
Quoth chown(2), Linux man-pages project:
Only a privileged process (Linux: one with the CAP_CHOWN capability)
may change the owner of a file.
Quoth chown(2), FreeBSD:
[EPERM] The operation would change the ownership,
but the effective user ID is not the super-user.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11834
There simply isn't a need for one, since the flags the daemon takes
are all short (mostly just toggles) and administrative in nature,
and are therefore better served by the age-old tradition of sourcing an
environment file and preparing the cmdline in the init-specific handler
itself, if needed at all
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11834
/dev/fd on Darwin
Consider the following strace output:
prlimit64(0, RLIMIT_NOFILE, NULL, {rlim_cur=1024, rlim_max=1024*1024}) = 0
Yes, that is well over a million file descriptors!
This reduces the ZED start-up time from "at least a second" to
"instantaneous", and, under strace, from "don't even try" to "usable"
by simple virtue of doing five syscalls instead of over a million;
in most cases the main loop does nothing
Recent Linuxes (5.8+) have close_range(2) for this, but that's an
overoptimisation (and libcs don't have wrappers for it yet)
This is also run by the ZEDLET pre-exec. Compare:
Finished "all-syslog.sh" eid=13 pid=6717 time=1.027100s exit=0
Finished "history_event-zfs-list-cacher.sh" eid=13 pid=6718 time=1.046923s exit=0
to
Finished "all-syslog.sh" eid=12 pid=4834 time=0.001836s exit=0
Finished "history_event-zfs-list-cacher.sh" eid=12 pid=4835 time=0.001346s exit=0
lol
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11834
200ms time-out is relatively long, but if we already hit the cap,
then we'll likely be able to spawn multiple new jobs when we wake up
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11807
The FIXME comment was there since the initial implementation in 2014,
there are no users
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11807
rpm/redhat/zfs-kmod.spec.in has a typo in the shell code that
creates the kmod-preamble file. This typo results in the
preamble file having the wrong name,
./SOURCES/kmod-preamblenObsoletes
and missing the Obsoletes clause that has become part of the name.
Because the filename is incorrect, the built package does not have
"obsoletes" or "conflicts" set.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes#11851
In order for package managers such as dnf to upgrade cleanly after
the package SONAME bump the obsolete package names must be known.
Update the new packages to correctly obsolete the old ones.
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#11844Closes#11847
This effectively reverts
4fc411f7a3 (part of #6807) and
f6fbe25664 (#9042) ‒
the code itself and latter PR cite symmetry with whole-disk-vdev
behaviour (presumably because rootfs vdevs are rarely whole disks),
but the code is broken for NVME devices (indeed, it'd strip the
controller number instead of the (potential) partition number, turning
"nvme0n1p1" into "nvmen1p1", which would then subsequently fail the
sysfs existence check); it could be fixed to handle those (and any
others) rather easily by dereferencing /sys/class/block/$devname,
but this isn't the place for setting this ‒ as noted in the commit that
removed setting the scheduler by default
(9e17e6f254) ‒ use an udev rule
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11838
IFS= would break loops in import_pool(), which would fault
any automatic import
Additionally $ZFS_BOOTFS from cmdline would interfere with find_rootfs()
If many pools were present, same thing could happen across multiple
find_rootfs() runs, so bail out early and clean up in error path
Suggested-by: @nachtgeist
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11278Closes#11838
get_clones_string currently returns an empty string for filesystem
snapshots which have no clones. This breaks parsable `zfs get` output as
only three columns are output, instead of 4.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Fiddaman <github@m.fiddaman.uk>
Co-authored-by: matt <matt@fiddaman.net>
Closes#11837
The exact limitations on what features are supported when booting
vary considerably depending on the environment. In order to minimize
confusion avoid categorical statements which assume GRUB2 is being
used. The supported GRUB2 features are covered earlier in this man
page for easy reference.
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11842
In addition, html doc will have working hyperlinks.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: George Melikov <mail@gmelikov.ru>
Closes#11845
zpool list, which is the only user, would mistakenly try to parse the
empty string as the interval in this case:
$ zpool list "a"
cannot open 'a': no such pool
$ zpool list ""
interval cannot be zero
usage: <usage string follows>
which is now symmetric with zpool get:
$ zpool list ""
cannot open '': name must begin with a letter
Avoid breaking the "interval cannot be zero" string.
There simply isn't a need for this, and it's user-facing.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11841Closes#11843
The pool_checkpoint tests may incorrectly fail because several of
them invoke zdb for an imported pool. In this scenario it's not
unexpected for zdb to fail if the pool is modified. To resolve
this these zdb checks are now done after the pool has been exported.
Additionally, the default cleanup functions assumed the pool would
be imported when they were run. If this was not the case they're
exit early and fail to cleanup all of the test state causing
subsequent tests to fail. Add a check to only destroy the pool
when it is imported.
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#11832
Correct an assortment of typos throughout the code base.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes#11774
/dev/zfs is 0:0 666 on most systems, so the [ -w /dev/zfs ] check always
succeeds, but if zfs isn't in $PATH (e.g. when completing from
"/sbin/zfs list" on a regular account) this can lead to error spew like
nabijaczleweli@szarotka:~$ /sbin/zfs list bash: zfs: command not found
@ bash: zfs: command not found
We only do read-only commands, and quite general ones at that,
so there's no need to elevate one way or another.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11828
Document the project's policy regarding publishing and maintaining
official OpenZFS releases.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#11821
Add inheritance/inherit_001_pos to the maybe fails on FreeBSD list.
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#11830
Bump the library versions as advised by the libtool guidelines.
https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
Two new functions were added but no existing functions were changed,
so we increase the version and the age (version:revision:age).
Added functions (2):
- boolean_t zpool_is_draid_spare(const char *);
- zpool_compat_status_t zpool_load_compat(const char *,
boolean_t *, char *, char *);
Additionally bump the libzpool.so version information. This library
is for internal use but we still want to update the version to track
major changes to the interfaces.
The libzfsbootenv, libuutil, libnvpair and libzfs_core libraries
have not been updated.
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#11817
Nothing bad happens if a prefix of your pool name matches a disk name.
This is a bit of a silly restriction at this point.
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Ryan Moeller <freqlabs@FreeBSD.org>
Closes#11781Closes#11813
The lower bound for this scaling to too low and the upper bound is too
high. Use a fixed default length of 512 instead, which is a reasonable
value on any system.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#11822
ratelimit_dropped isn't protected by a lock and is expected to
be updated atomically.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#11822
Recently we've been running out of free space in the ubuntu 20.04
environment resulting in test failures. This appears to be caused
by a change in the default available free space and not because of
any change in OpenZFS. Try and avoid this failure by applying a
suggested workaround which removes some unnecessary files.
https://github.com/actions/virtual-environments/issues/2840
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#11826
The configure check for iops->rename wanting flags was missing the
AC_MSG_CHECKING() so it would just print yes without saying what was
being checked.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes#11825
Update the fsck.zfs helper to bubble up some already-known-about
errors if they are detected in the pool.
health=degraded => 4/"Filesystem errors left uncorrected"
health=faulted && dataset in /etc/fstab => 8/"Operational error"
pool not found => 8/"Operational error"
everything else => 0
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11806
ZoL 0.6.1 introduced feature flags with the three features that all
implementations at the time were guaranteed to have. 0.6.4 introduced
a few more until 0.6.5 added two after that. OpenZFS 2.1 added the
dRAID feature.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mike Swanson <mikeonthecomputer@gmail.com>
Closes#11818
When a child process is killed waitpid() must be called on the
pid the reap the zombie process.
Update BUGS section to reflect reality by replacing "zedlets
aren't time limited with "zedlets can be interrupted".
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#11769Closes#11798
For gang blocks, `DVA_GET_ASIZE()` is the total space allocated for the
gang DVA including its children BP's. The space allocated at each DVA's
vdev/offset is `vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE)`.
This commit makes this relationship more clear by using a helper
function, `vdev_gang_header_asize()`, for the space allocated at the
gang block's vdev/offset.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#11744
When specifying the name of a RAIDZ vdev on the command line, it can be
specified as raidz-<vdevID> or raidzP-<vdevID>.
e.g. `zpool clear poolname raidz-0` or `zpool clear poolname raidz2-0`
If the parity is specified in the vdev name, it should match the actual
parity of that RAIDZ vdev, otherwise the command should fail. This
commit makes it so.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Stuart Maybee <stuart.maybee@comcast.net>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#11742
Other (all?) Linux filesystems seem to return -EPERM instead of -EACCESS
when trying to set FS_APPEND_FL or FS_IMMUTABLE_FL without the
CAP_LINUX_IMMUTABLE capability. This was detected by generic/545 test
in the fstest suite.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Luis Henriques <henrix@camandro.org>
Closes#11791
Arm-based Macs are like FreeBSD and provide a full 64-bit stat from the
start, so have no stat64 variants. Thus, define stat64 and fstat64 as
aliases for the normal versions.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Closes#11771
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes#11775
To make better predictions on parallel workloads dmu_zfetch() should
be called as early as possible to reduce possible request reordering.
In particular, it should be called before dmu_buf_hold_array_by_dnode()
calls dbuf_hold(), which may sleep waiting for indirect blocks, waking
up multiple threads same time on completion, that can significantly
reorder the requests, making the stream look like random. But we
should not issue prefetch requests before the on-demand ones, since
they may get to the disks first despite the I/O scheduler, increasing
on-demand request latency.
This patch splits dmu_zfetch() into two functions: dmu_zfetch_prepare()
and dmu_zfetch_run(). The first can be executed as early as needed.
It only updates statistics and makes predictions without issuing any
I/Os. The I/O issuance is handled by dmu_zfetch_run(), which can be
called later when all on-demand I/Os are already issued. It even
tracks the activity of other concurrent threads, issuing the prefetch
only when _all_ on-demand requests are issued.
For many years it was a big problem for storage servers, handling
deeper request queues from their clients, having to either serialize
consequential reads to make ZFS prefetcher usable, or execute the
incoming requests as-is and get almost no prefetch from ZFS, relying
only on deep enough prefetch by the clients. Benefits of those ways
varied, but neither was perfect. With this patch deeper queue
sequential read benchmarks with CrystalDiskMark from Windows via
iSCSI to FreeBSD target show me much better throughput with almost
100% prefetcher hit rate, comparing to almost zero before.
While there, I also removed per-stream zs_lock as useless, completely
covered by parent zf_lock. Also I reused zs_blocks refcount to track
zf_stream linkage of the stream, since I believe previous zs_fetch ==
NULL check in dmu_zfetch_stream_done() was racy.
Delete prefetch streams when they reach ends of files. It saves up
to 1KB of RAM per file, plus reduces searches through the stream list.
Block data prefetch (speculation and indirect block prefetch is still
done since they are cheaper) if all dbufs of the stream are already
in DMU cache. First cache miss immediately fires all the prefetch
that would be done for the stream by that time. It saves some CPU
time if same files within DMU cache capacity are read over and over.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Adam Moss <c@yotes.com>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#11652
If TX_WRITE is create on a file, and the file is later deleted and a new
directory is created on the same object id, it is possible that when
zil_commit happens, zfs_get_data will be called on the new directory.
This may result in panic as it tries to do range lock.
This patch fixes this issue by record the generation number during
zfs_log_write, so zfs_get_data can check if the object is valid.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes#10593Closes#11682
Commit 235a85657 introduced a regression in evaluation of POSIX modes
that require group DENY entries in the internal ZFS ACL. An example
of such a POSX mode is 007. When write_implies_delete_child is set,
then ACE_WRITE_DATA is added to `wanted_dirperms` in prior to calling
zfs_zaccess_common(). This occurs is zfs_zaccess_delete().
Unfortunately, when zfs_zaccess_aces_check hits this particular DENY
ACE, zfs_groupmember() is checked to determine whether access should be
denied, and since zfs_groupmember() always returns B_TRUE on Linux and
so this check is failed, resulting ultimately in EPERM being returned.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Andrew Walker <awalker@ixsystems.com>
Closes#11760
This change adds a new test that covers a bug fix in the binary search
in the redacted send resume logic that causes a kernel panic.
The bug was fixed in https://github.com/openzfs/zfs/pull/11297.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: John Kennedy <john.kennedy@delphix.com>
Signed-off-by: Palash Gandhi <palash.gandhi@delphix.com>
Closes#11764
The FreeBSD boot loader relies on the bootfs property and is capable
of booting from removed (indirect) vdevs.
Reviewed-by Eric van Gyzen
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Martin Matuska <mm@FreeBSD.org>
Closes#11763
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#11770
It used to be required to pass a enum km_type to kmap_atomic() and
kunmap_atomic(), however this is no longer necessary and the wrappers
zfs_k(un)map_atomic removed these. This is confusing in the ABD code as
the struct abd_iter member iter_km no longer exists and the wrapper
macros simply compile them out.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Adam Moss <c@yotes.com>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes#11768
= Motivation
We've noticed several zloop crashes within Delphix generated
due to the following sequence of events:
- A device gets expanded and new metaslabas are allocated for
it. These metaslabs go through `metaslab_init()` but haven't
gone through `metaslab_sync_done()` yet. This meas that the
only range tree that's actually set is the `ms_allocatable`.
All the others are NULL.
- A vdev_initialization is issues and `vdev_initialize_thread`
starts processing one of these new metaslabs of the expanded
vdev.
- As part of `vdev_initialize_calculate_progress()` we call
into `metaslab_load()` and `metaslab_load_impl()` which
in turn tries to dereference the metaslabs trees that
are still NULL and therefore we crash.
The same failure can come up from the `vdev_trim` code paths.
= This Patch
We considered the following solutions to deal with this issue:
[A] Add logic to `vdev_initialize/trim` to skip those new
metaslabs. We decided against this as it would be good
to avoid exposing this lower-level detail to higer-level
operations.
[B] Have `metaslab_load_impl()` return early for new metaslabs
and thus never touch those range_trees that are NULL at
that time. This seemed more of a work-around for the bug
and not a clear-cut solution.
[C] Refactor our logic so all metaslabs have their range_trees
created at the time of their creatin in `metaslab_init()`.
In this patch we decided to go with [C] because:
(1) It doesn't expose more metaslab details to higher level
operations such as vdev initialize and trim.
(2) The current behavior of creating the range trees lazily
in `metaslab_sync_done()` is unnecessarily complicated.
(3) Always initializing the metaslab range_trees makes other
parts of the codebase cleaner. For example, we used to
use `ms_freed` as the reference value for knowing whether
all the range_trees have been initialized. Now we no
longer need to do that check in most places (and in the
few that we do we use the `ms_new` boolean field now
which is more readable).
= Side Changes
Probably due to a mismerge we set `ms_loaded` to `B_TRUE` twice
in `metasloab_load_impl()`. In this patch we remove the extraneous
assignment.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes#11737
The BIO_MAX_PAGES macro is being retired in favor of a bio_max_segs()
function that implements the typical MIN(x,y) logic used throughout the
kernel for bounding the allocation, and also the new implementation is
intended to be signed-safe (which the former was not).
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#11765
In Linux 5.12, the filesystem API was modified to support ipmapped
mounts by adding a "struct user_namespace *" parameter to a number
functions and VFS handlers. This change adds the needed autoconf
macros to detect the new interfaces and updates the code appropriately.
This change does not add support for idmapped mounts, instead it
preserves the existing behavior by passing the initial user namespace
where needed. A subsequent commit will be required to add support
for idmapped mounted.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes#11712
The RAIDZ and DRAID code is responsible for reporting checksum errors on
their child vdevs. Checksum errors represent events where a disk
returned data or parity that should have been correct, but was not. In
other words, these are instances of silent data corruption. The
checksum errors show up in the vdev stats (and thus `zpool status`'s
CKSUM column), and in the event log (`zpool events`).
Note, this is in contrast with the more common "noisy" errors where a
disk goes offline, in which case ZFS knows that the disk is bad and
doesn't try to read it, or the device returns an error on the requested
read or write operation.
RAIDZ/DRAID generate checksum errors via three code paths:
1. When RAIDZ/DRAID reconstructs a damaged block, checksum errors are
reported on any children whose data was not used during the
reconstruction. This is handled in `raidz_reconstruct()`. This is the
most common type of RAIDZ/DRAID checksum error.
2. When RAIDZ/DRAID is not able to reconstruct a damaged block, that
means that the data has been lost. The zio fails and an error is
returned to the consumer (e.g. the read(2) system call). This would
happen if, for example, three different disks in a RAIDZ2 group are
silently damaged. Since the damage is silent, it isn't possible to know
which three disks are damaged, so a checksum error is reported against
every child that returned data or parity for this read. (For DRAID,
typically only one "group" of children is involved in each io.) This
case is handled in `vdev_raidz_cksum_finish()`. This is the next most
common type of RAIDZ/DRAID checksum error.
3. If RAIDZ/DRAID is not able to reconstruct a damaged block (like in
case 2), but there happens to be additional copies of this block due to
"ditto blocks" (i.e. multiple DVA's in this blkptr_t), and one of those
copies is good, then RAIDZ/DRAID compares each sector of the data or
parity that it retrieved with the good data from the other DVA, and if
they differ then it reports a checksum error on this child. This
differs from case 2 in that the checksum error is reported on only the
subset of children that actually have bad data or parity. This case
happens very rarely, since normally only metadata has ditto blocks. If
the silent damage is extensive, there will be many instances of case 2,
and the pool will likely be unrecoverable.
The code for handling case 3 is considerably more complicated than the
other cases, for two reasons:
1. It needs to run after the main raidz read logic has completed. The
data RAIDZ read needs to be preserved until after the alternate DVA has
been read, which necessitates refcounts and callbacks managed by the
non-raidz-specific zio layer.
2. It's nontrivial to map the sections of data read by RAIDZ to the
correct data. For example, the correct data does not include the parity
information, so the parity must be recalculated based on the correct
data, and then compared to the parity that was read from the RAIDZ
children.
Due to the complexity of case 3, the rareness of hitting it, and the
minimal benefit it provides above case 2, this commit removes the code
for case 3. These types of errors will now be handled the same as case
2, i.e. the checksum error will be reported against all children that
returned data or parity.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#11735
наб
Brian Behlendorf
Olaf Faaland
matt-fidd
George Melikov
Andrea Gelmini
Ryan Moeller
Brian Atkinson
Mike Swanson
Matthew Ahrens
Luis Henriques
Jessica Clarke
Alexander Motin
Chunwei Chen
Andrew
Palash Gandhi
Martin Matuška
Serapheim Dimitropoulos
Coleman Kane