Commit Graph

3997 Commits

Author SHA1 Message Date
Richard Yao 856cefcd1c
Cleanup ->dd_space_towrite should be unsigned
This is only ever used with unsigned data, so the type itself should be
unsigned. Also, PVS Studio's 2016 FreeBSD kernel report correctly
identified the following assertion as always being true, so we can drop
it:

ASSERT3U(dd->dd_space_towrite[i & TXG_MASK], >=, 0);

The reason it was always true is because it would do casts to give us
unsigned comparisons. This could have been fixed by switching to
`ASSERT3S()`, but upon inspection, it turned out that this variable
never should have been allowed to be signed in the first place.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14408
2023-01-20 11:10:15 -08:00
Mark Johnston ebabb93e6c Micro-optimize dsl_prop_get_dd()
Use the saved property index instead of looking it up once per DSL
directory when traversing up towards the root.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Akash B <akash-b@hpe.com>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Sponsored-by: The FreeBSD Foundation
Closes #14397
2023-01-20 11:01:41 -08:00
Mark Johnston 7c30100c00 Avoid passing an uninitialized index to dsl_prop_known_index
Reported-by: KMSAN
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Akash B <akash-b@hpe.com>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Sponsored-by: The FreeBSD Foundation
Closes #14397
2023-01-20 11:00:38 -08:00
Chunwei Chen c6dab6dd39
Fix unprotected zfs_znode_dmu_fini
In original code, zfs_znode_dmu_fini is called in zfs_rmnode without
zfs_znode_hold_enter. It seems to assume it's ok to do so when the znode
is unlinked. However this assumption is not correct, as zfs_zget can be
called by NFS through zpl_fh_to_dentry as pointed out by Christian in
https://github.com/openzfs/zfs/pull/12767, which could result in a
use-after-free bug.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes #12767 
Closes #14364
2023-01-19 16:59:05 -08:00
Jorgen Lundman 68c0771cc9
Unify Assembler files between Linux and Windows
Add new macro ASMABI used by Windows to change
calling API to "sysv_abi".

Reviewed-by: Attila Fülöp <attila@fueloep.org>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jorgen Lundman <lundman@lundman.net>
Closes #14228
2023-01-17 11:09:19 -08:00
Richard Yao 2e7f664f04
Cleanup of dead code suggested by Clang Static Analyzer (#14380)
I recently gained the ability to run Clang's static analyzer on the
linux kernel modules via a few hacks. This extended coverage to code
that was previously missed since Clang's static analyzer only looked at
code that we built in userspace. Running it against the Linux kernel
modules built from my local branch produced a total of 72 reports
against my local branch. Of those, 50 were reports of logic errors and
22 were reports of dead code. Since we already had cleaned up all of
the previous dead code reports, I felt it would be a good next step to
clean up these dead code reports. Clang did a further breakdown of the
dead code reports into:

Dead assignment	15

Dead increment	2

Dead nested assignment	5

The benefit of cleaning these up, especially in the case of dead nested
assignment, is that they can expose places where our error handling is
incorrect. A number of them were fairly straight forward. However
several were not:

In vdev_disk_physio_completion(), not only were we not using the return
value from the static function vdev_disk_dio_put(), but nothing used it,
so I changed it to return void and removed the existing (void) cast in
the other area where we call it in addition to no longer storing it to a
stack value.

In FSE_createDTable(), the function is dead code. Its helper function
FSE_freeDTable() is also dead code, as are the CPP definitions in
`module/zstd/include/zstd_compat_wrapper.h`. We just delete it all.

In zfs_zevent_wait(), we have an optimization opportunity. cv_wait_sig()
returns 0 if there are waiting signals and 1 if there are none. The
Linux SPL version literally returns `signal_pending(current) ? 0 : 1)`
and FreeBSD implements the same semantics, we can just do
`!cv_wait_sig()` in place of `signal_pending(current)` to avoid
unnecessarily calling it again.

zfs_setattr() on FreeBSD version did not have error handling issue
because the code was removed entirely from FreeBSD version. The error is
from updating the attribute directory's files. After some thought, I
decided to propapage errors on it to userspace.

In zfs_secpolicy_tmp_snapshot(), we ignore a lack of permission from the
first check in favor of checking three other permissions. I assume this
is intentional.

In zfs_create_fs(), the return value of zap_update() was not checked
despite setting an important version number. I see no backward
compatibility reason to permit failures, so we add an assertion to catch
failures. Interestingly, Linux is still using ASSERT(error == 0) from
OpenSolaris while FreeBSD has switched to the improved ASSERT0(error)
from illumos, although illumos has yet to adopt it here. ASSERT(error ==
0) was used on Linux while ASSERT0(error) was used on FreeBSD since the
entire file needs conversion and that should be the subject of
another patch.

dnode_move()'s issue was caused by us not having implemented
POINTER_IS_VALID() on Linux. We have a stub in
`include/os/linux/spl/sys/kmem_cache.h` for it, when it really should be
in `include/os/linux/spl/sys/kmem.h` to be consistent with
Illumos/OpenSolaris. FreeBSD put both `POINTER_IS_VALID()` and
`POINTER_INVALIDATE()` in `include/os/freebsd/spl/sys/kmem.h`, so we
copy what it did.

Whenever a report was in platform-specific code, I checked the FreeBSD
version to see if it also applied to FreeBSD, but it was only relevant a
few times.

Lastly, the patch that enabled Clang's static analyzer to be run on the
Linux kernel modules needs more work before it can be put into a PR. I
plan to do that in the future as part of the on-going static analysis
work that I am doing.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14380
2023-01-17 09:57:12 -08:00
Richard Yao d27c7ba62f
Linux ppc64le ieee128 compat: Do not redefine __asm on external headers
There is an external assembly declaration extension in GNU C that glibc
uses when building with ieee128 floating point support on ppc64le.
Marking that as volatile makes no sense, so the build breaks.

It does not make sense to only mark this as volatile on Linux, since if
do not want the compiler reordering things on Linux, we do not want the
compiler reordering things on any other platform, so we stop treating
Linux specially and just manually inline the CPP macro so that we can
eliminate it. This should fix the build on ppc64le.

Tested-by: @gyakovlev 
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14308
Closes #14384
2023-01-13 10:58:58 -08:00
Richard Yao 4ef69de384 Cleanup: Use NULL when doing NULL pointer comparisons
The Linux 5.16.14 kernel's coccicheck caught this. The semantic
patch that caught it was:

./scripts/coccinelle/null/badzero.cocci

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 16:00:37 -08:00
Richard Yao 64195fc89f Cleanup: Remove unneeded semicolons
The Linux 5.16.14 kernel's coccicheck caught this. The semantic
patch that caught it was:

./scripts/coccinelle/misc/semicolon.cocci

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 16:00:30 -08:00
Richard Yao 3b2f9c1ec8 Cleanup: Use MIN() macro
The Linux 5.16.14 kernel's coccicheck caught this. The semantic
patch that caught it was:

./scripts/coccinelle/misc/minmax.cocci

There was a third opportunity to use `MIN()`, but that was in
`FSE_minTableLog()` in `module/zstd/lib/compress/fse_compress.c`.
Upstream zstd has yet to make this change and I did not want to change
header includes just for MIN, or do a one off, so I left it alone.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 16:00:23 -08:00
Richard Yao e6328fda2e Cleanup: !A || A && B is equivalent to !A || B
In zfs_zaccess_dataset_check(), we have the following subexpression:

(!IS_DEVVP(ZTOV(zp)) ||
    (IS_DEVVP(ZTOV(zp)) && (v4_mode & WRITE_MASK_ATTRS)))

When !IS_DEVVP(ZTOV(zp)) is false, IS_DEVVP(ZTOV(zp)) is true under the
law of the excluded middle since we are not doing pseudoboolean alegbra.
Therefore doing:

(IS_DEVVP(ZTOV(zp)) && (v4_mode & WRITE_MASK_ATTRS))

Is unnecessary and we can just do:

(v4_mode & WRITE_MASK_ATTRS)

The Linux 5.16.14 kernel's coccicheck caught this. The semantic
patch that caught it was:

./scripts/coccinelle/misc/excluded_middle.cocci

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 16:00:15 -08:00
Richard Yao 9c8fabffa2 Cleanup: Replace oldstyle struct hack with C99 flexible array members
The Linux 5.16.14 kernel's coccicheck caught this. The semantic
patch that caught it was:

./scripts/coccinelle/misc/flexible_array.cocci

However, unlike the cases where the GNU zero length array extension had
been used, coccicheck would not suggest patches for the older style
single member arrays. That was good because blindly changing them would
break size calculations in most cases.

Therefore, this required care to make sure that we did not break size
calculations. In the case of `indirect_split_t`, we use
`offsetof(indirect_split_t, is_child[is->is_children])` to calculate
size. This might be subtly wrong according to an old mailing list
thread:

https://inbox.sourceware.org/gcc-prs/20021226123454.27019.qmail@sources.redhat.com/T/

That is because the C99 specification should consider the flexible array
members to start at the end of a structure, but compilers prefer to put
padding at the end. A suggestion was made to allow compilers to allocate
padding after the VLA like compilers already did:

http://std.dkuug.dk/JTC1/SC22/WG14/www/docs/n983.htm

However, upon thinking about it, whether or not we allocate end of
structure padding does not matter, so using offsetof() to calculate the
size of the structure is fine, so long as we do not mix it with sizeof()
on structures with no array members.

In the case that we mix them and padding causes offsetof(struct_t,
vla_member[0]) to differ from sizeof(struct_t), we would be doing unsafe
operations if we underallocate via `offsetof()` and then overcopy via
sizeof().

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 16:00:03 -08:00
Richard Yao d35ccc1f59 Cleanup: Fix indentation in zfs_dbgmsg_t
fdc2d30371 accidentally broke the
indentation.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 15:59:56 -08:00
Richard Yao 8e7ebf4e2d Cleanup: Use C99 flexible array members instead of zero length arrays
The Linux 5.16.14 kernel's coccicheck caught this. The semantic
patch that caught it was:

./scripts/coccinelle/misc/flexible_array.cocci

The Linux kernel's documentation makes a good case for why we should not
use these:

https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 15:59:41 -08:00
Richard Yao c9c3ce7976 Cleanup: Use kmem_zalloc() instead of memset() to zero memory
The Linux 5.16.14 kernel's coccicheck caught this. The semantic patch
that caught it was:

./scripts/coccinelle/api/alloc/zalloc-simple.cocci

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 15:59:28 -08:00
Richard Yao 7384ec65cd Cleanup: Remove unnecessary explicit casts of pointers from allocators
The Linux 5.16.14 kernel's coccicheck caught these. The semantic patch
that caught them was:

./scripts/coccinelle/api/alloc/alloc_cast.cocci

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14372
2023-01-12 15:59:12 -08:00
George Amanakis eee9362a72
Activate filesystem features only in syncing context
When activating filesystem features after receiving a snapshot, do 
so only in syncing context.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes #14304 
Closes #14252
2023-01-11 18:00:39 -08:00
Mateusz Piotrowski 926715b9fc
Turn default_bs and default_ibs into ZFS_MODULE_PARAMs
The default_bs and default_ibs tunables control the default block size
and indirect block size.

So far, default_bs and default_ibs were tunable only on FreeBSD, e.g.,

    sysctl vfs.zfs.default_ibs

Remove the FreeBSD-specific sysctl code and expose default_bs and
default_ibs as tunables on both Linux and FreeBSD using
ZFS_MODULE_PARAM.

One of the use cases for changing the values of those tunables is to
lower the indirect block size, which may improve performance of large
directories (as discussed during the OpenZFS Leadership Meeting
on 2022-08-16).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Mateusz Piotrowski <mateusz.piotrowski@klarasystems.com>
Sponsored-by: Wasabi Technology, Inc.
Closes #14293
2023-01-11 09:38:20 -08:00
Mateusz Piotrowski a4b21eadec
Add tunable to allow changing micro ZAP's max size
This change turns `MZAP_MAX_BLKSZ` into a `ZFS_MODULE_PARAM()` called
`zap_micro_max_size`. As a result, we can experiment with different
micro ZAP sizes to improve directory size scaling.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Mateusz Piotrowski <mateuszpiotrowski@klarasystems.com>
Co-authored-by: Toomas Soome <toomas.soome@klarasystems.com>
Signed-off-by: Mateusz Piotrowski <mateuszpiotrowski@klarasystems.com>
Sponsored-by: Wasabi Technology, Inc.
Closes #14292
2023-01-10 13:41:54 -08:00
Matthew Ahrens fc45975ec8
Batch enqueue/dequeue for bqueue
The Blocking Queue (bqueue) code is used by zfs send/receive to send
messages between the various threads.  It uses a shared linked list,
which is locked whenever we enqueue or dequeue.  For workloads which
process many blocks per second, the locking on the shared list can be
quite expensive.

This commit changes the bqueue logic to have 3 linked lists:
1. An enquing list, which is used only by the (single) enquing thread,
   and thus needs no locks.
2. A shared list, with an associated lock.
3. A dequing list, which is used only by the (single) dequing thread,
   and thus needs no locks.

The entire enquing list can be moved to the shared list in constant
time, and the entire shared list can be moved to the dequing list in
constant time.  These operations only happen when the `fill_fraction` is
reached, or on an explicit flush request.  Therefore, the lock only
needs to be acquired infrequently.

The API already allows for dequing to block until an explicit flush, so
callers don't need to be changed.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #14121
2023-01-10 13:39:22 -08:00
Brian Behlendorf 0c8fbe5b6a ztest: update ztest_dmu_snapshot_create_destroy()
ECHRNG is returned when the channel program encounters a runtime
error.  For example, this can happen when a snapshot doesn't exist.
We handle this error the same way as the existing EEXIST and ENOENT
error checks.

Additionally, improve the internal debug message to include the
error describing why a pool couldn't be opened.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #14351
2023-01-10 13:27:48 -08:00
Matthew Ahrens 40d7e971ff
ztest fails assertion in zio_write_gang_member_ready()
Encrypted blocks can have up to 2 DVA's, as the third DVA is reserved
for the salt+IV.  However, dmu_write_policy() allows non-encrypted
blocks (e.g. DMU_OT_OBJSET) inside encrypted datasets to request and
allocate 3 DVA's, since they don't need a salt+IV (they are merely
authenicated).

However, if such a block becomes a gang block, the gang code incorrectly
limits the gang block header to 2 DVA's.  This leads to a "NDVAs
inversion", where a parent block (the gang block header) has less DVA's
than its children (the gang members), causing an assertion failure in
zio_write_gang_member_ready().

This commit addresses the problem by only restricting the gang block
header to 2 DVA's if the block is actually encrypted (and thus its gang
block members can have at most 2 DVA's).

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #14250
Closes #14356
2023-01-09 16:43:45 -08:00
Ameer Hamza 5091867ee6
zed: add hotplug support for spare vdevs
This commit supports for spare vdev hotplug. The
spare vdev associated with all the pools will be
marked as "Removed" when the drive is physically
detached and will become "Available" when the
drive is reattached. Currently, the spare vdev
status does not change on the drive removal and
the same is the case with reattachment.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes #14295
2023-01-09 12:43:03 -08:00
Alexander Motin 289f7e6adb
Remove some dead ARC code. (#14340)
Every ARC buffer holds a reference on the header. It means headers with
buffers are never evictable.  When we are evicting a header, there can
be no more buffers to free.  Just assert that.

b_evict_lock seems not protecting anything now.  Remove it.

Buffers checksum should also be freed with the last uncompressed buffer,
so it should not be there also when we are evicting the header.

Signed-off-by:  Alexander Motin <mav@FreeBSD.org>
Sponsored by:   iXsystems, Inc.
2023-01-09 10:45:17 -08:00
Coleman Kane 884a69357f linux 6.2 compat: get_acl() got moved to get_inode_acl() in 6.2
Linux 6.2 renamed the get_acl() operation to get_inode_acl() in
the inode_operations struct. This should fix Issue #14323.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #14323
Closes #14331
2023-01-06 14:40:54 -08:00
Antonio Russo d27c81847b Linux 6.1 compat: open inside tmpfile()
Linux 863f144 modified the .tmpfile interface to pass a struct file,
rather than a struct dentry, and expect the tmpfile implementation to
open inside of tmpfile().

This patch implements a configuration test that checks for this new API
and appropriately sets a HAVE_TMPFILE_DENTRY flag that tracks this old
API.  Contingent on this flag, the appropriate API is implemented.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Antonio Russo <aerusso@aerusso.net>
Closes #14301
Closes #14343
2023-01-06 14:33:00 -08:00
Richard Yao 1f3bc5ea80
Illumos #15286: do_composition() needs sign awareness
Authored by: Dan McDonald <danmcd@mnx.io>
Reviewed by: Patrick Mooney <pmooney@pfmooney.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Approved by: Joshua M. Clulow <josh@sysmgr.org>
Ported-by: Richard Yao <richard.yao@alumni.stonybrook.edu>

Illumos-issue: https://www.illumos.org/issues/15286
Illumos-commit: f137b22e73

Porting Notes:

The patch in illumos did not have much of a commit message, and did not
provide attribution to the reporter, while original patch proposed to
OpenZFS did, so I am listing the reporter (myself) and original patch
author (also myself) below while including the original commit message
with some minor corrections as part of the porting notes:

In do_composition(), we have:

size = u8_number_of_bytes[*p];
if (size <= 1 || (p + size) > oslast)
	break;

There, we have type promotion from int8_t to size_t, which is unsigned.
C will sign extend the value as part of the widening before treating the
value as unsigned and the negative values we can counter are error
values from U8_ILLEGAL_CHAR and U8_OUT_OF_RANGE_CHAR, which are -1 and
-2 respectively. The unsigned versions of these under two's complement
are SIZE_MAX and SIZE_MAX-1 respectively.

The bounds check is written under the assumption that `size <= 1` does a
signed comparison. This is followed by a pointer comparison to see if
the string has the correct length, which is fine.

A little further down we have:

for (i = 0; i < size; i++)
	tc[i] = *p++;

When an error condition is encountered, this will attempt to iterate at
least SIZE_MAX-1 times, which will massively overflow the buffer, which
is not fine.

The kernel will kill the loop as soon as it hits the kernel stack guard
on Linux systems built with CONFIG_VMAP_STACK=y, which should be just
about all of them. That prevents arbitrary code execution and just about
any other bad thing that a black hat attacker might attempt with
knowledge of this buffer overflow. Other systems' kernels have
mitigations for unbounded in-kernel buffer overflows that will catch
this too.

Also, the patch in illumos-gate made an effort to fix C style issues
that had been fixed in the OpenZFS/ZFSOnLinux repository. Those issues
had been mentioned in the email that I originally sent them about this
issue. One of the fixes had not been already done, so it is included.
Another to collect_a_seq()'s arguments was handled differently in
OpenZFS. For the sake of avoiding unnecessary differences, it has been
adopted. This has the interesting effect that if you correct the paths
in the illumos-gate patch to match the current OpenZFS repository, you
can reverse apply it cleanly.

Original-patch-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reported-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Co-authored-by: Dan McDonald <danmcd@mnx.io>
Closes #14318
Closes #14342
2023-01-05 11:16:21 -08:00
Mateusz Guzik f25f1f9091
FreeBSD: catch up to 1400077
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes #14328
2023-01-05 10:56:40 -08:00
Alexander Motin bacf366fe2
Hide b_freeze_* under ZFS_DEBUG
This saves 40 bytes per full ARC header, reducing it on FreeBSD from
240 to 200 bytes on production bits.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Closes #14315
2023-01-05 10:15:31 -07:00
Alexander Motin ed2f7ba08d
Implement uncached prefetch
Previously the primarycache property was handled only in the dbuf
layer. Since the speculative prefetcher is implemented in the ARC,
it had to be disabled for uncacheable buffers.

This change gives the ARC knowledge about uncacheable buffers
via  arc_read() and arc_write(). So when remove_reference() drops
the last reference on the ARC header, it can either immediately destroy
it, or if it is marked as prefetch, put it into a new arc_uncached state. 
That state is scanned every second, evicting stale buffers that were
not demand read.

This change also tracks dbufs that were read from the beginning,
but not to the end.  It is assumed that such buffers may receive further
reads, and so they are stored in dbuf cache. If a following
reads reaches the end of the buffer, it is immediately evicted.
Otherwise it will follow regular dbuf cache eviction.  Since the dbuf
layer does not know actual file sizes, this logic is not applied to
the final buffer of a dnode.

Since uncacheable buffers should no longer stay in the ARC for long,
this patch also tries to optimize I/O by allocating ARC physical
buffers as linear to allow buffer sharing.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes #14243
2023-01-04 17:29:54 -07:00
Alexander Motin c935fe2e92
arc_read()/arc_access() refactoring and cleanup
ARC code was many times significantly modified over the years, that
created significant amount of tangled and potentially broken code.
This should make arc_access()/arc_read() code some more readable.

 - Decouple prefetch status tracking from b_refcnt.  It made sense
originally, but became highly cryptic over the years.  Move all the
logic into arc_access().  While there, clean up and comment state
transitions in arc_access().  Some transitions were weird IMO.
 - Unify arc_access() calls to arc_read() instead of sometimes calling
it from arc_read_done().  To avoid extra state changes and checks add
one more b_refcnt for ARC_FLAG_IO_IN_PROGRESS.
 - Reimplement ARC_FLAG_WAIT in case of ARC_FLAG_IO_IN_PROGRESS with
the same callback mechanism to not falsely account them as hits. Count
those as "iohits", an intermediate between "hits" and "misses". While
there, call read callbacks in original request order, that should be
good for fairness and random speculations/allocations/aggregations.
 - Introduce additional statistic counters for prefetch, accounting
predictive vs prescient and hits vs iohits vs misses.
 - Remove hash_lock argument from functions not needing it.
 - Remove ARC_FLAG_PREDICTIVE_PREFETCH, since it should be opposite
to ARC_FLAG_PRESCIENT_PREFETCH if ARC_FLAG_PREFETCH is set.  We may
wish to add ARC_FLAG_PRESCIENT_PREFETCH to few more places.
 - Fix few false positive tests found in the process.

Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14123
2022-12-22 12:10:24 -08:00
Ryan Moeller dc8c2f6158
FreeBSD: Fix potential boot panic with bad label
vdev_geom_read_pool_label() can leave NULL in configs.  Check for it
and skip consistently when generating rootconf.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes #14291
2022-12-22 11:50:09 -08:00
Matthew Ahrens 018f26041d
deadlock between spa_errlog_lock and dp_config_rwlock
There is a lock order inversion deadlock between `spa_errlog_lock` and
`dp_config_rwlock`:

A thread in `spa_delete_dataset_errlog()` is running from a sync task.
It is holding the `dp_config_rwlock` for writer (see
`dsl_sync_task_sync()`), and waiting for the `spa_errlog_lock`.

A thread in `dsl_pool_config_enter()` is holding the `spa_errlog_lock`
(see `spa_get_errlog_size()`) and waiting for the `dp_config_rwlock` (as
reader).

Note that this was introduced by #12812.

This commit address this by defining the lock ordering to be
dp_config_rwlock first, then spa_errlog_lock / spa_errlist_lock.
spa_get_errlog() and spa_get_errlog_size() can acquire the locks in this
order, and then process_error_block() and get_head_and_birth_txg() can
verify that the dp_config_rwlock is already held.

Additionally, a buffer overrun in `spa_get_errlog()` is corrected.  Many
code paths didn't check if `*count` got to zero, instead continuing to
overwrite past the beginning of the userspace buffer at `uaddr`.

Tested by having some errors in the pool (via `zinject -t data
/path/to/file`), one thread running `zpool iostat 0.001`, and another
thread runs `zfs destroy` (in a loop, although it hits the first time).
This reproduces the problem easily without the fix, and works with the
fix.

Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: George Amanakis <gamanakis@gmail.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #14239
Closes #14289
2022-12-22 11:48:49 -08:00
Doug Rabson 24502bd3a7
FreeBSD: Remove stray debug printf
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Doug Rabson <dfr@rabson.org>
Closes #14286 
Closes #14287
2022-12-13 17:35:07 -08:00
Richard Yao f3f5263f8a
Zero end of embedded block buffer in dump_write_embedded()
This fixes a kernel stack leak.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Tested-by: Nicholas Sherlock <n.sherlock@gmail.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #13778
Closes #14255
2022-12-13 17:31:47 -08:00
Richard Yao 3236c0b891
Cache dbuf_hash() calculation
We currently compute a 64-bit hash three times, which consumes 0.8% CPU
time on ARC eviction heavy workloads. Caching the 64-bit value in the
dbuf allows us to avoid that overhead.

Sponsored-By: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Richard Yao <richard.yao@klarasystems.com>
Closes #14251
2022-12-13 17:29:21 -08:00
Allan Jude dc95911d21
zfs list: Allow more fields in ZFS_ITER_SIMPLE mode
If the fields to be listed and sorted by are constrained to those
populated by dsl_dataset_fast_stat(), then zfs list is much faster,
as it does not need to open each objset and reads its properties.

A previous optimization by Pawel Dawidek
(0cee24064a) took advantage
of this to make listing snapshot names sorted only by name much faster.

However, it was limited to `-o name -s name`, this work extends this
optimization to work with:
  - name
  - guid
  - createtxg
  - numclones
  - inconsistent
  - redacted
  - origin
and could be further extended to any other properties supported by
dsl_dataset_fast_stat() or similar, that do not require extra locking
or reading from disk.

This was committed before (9a9e2e343d),
but was reverted due to a regression when used with an older kernel.

If the kernel does not populate zc->zc_objset_stats, we now fallback
to getting the properties via the slower interface, to avoid problems
with newer userland and older kernels.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Closes #14110
2022-12-13 17:27:54 -08:00
Ameer Hamza e3785718ba
Skip permission checks for extended attributes
zfs_zaccess_trivial() calls the generic_permission() to read
xattr attributes. This causes deadlock if called from
zpl_xattr_set_dir() context as xattr and the dent locks are
already held in this scenario. This commit skips the permissions
checks for extended attributes since the Linux VFS stack already
checks it before passing us the control.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Youzhong Yang <yyang@mathworks.com>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes #14220
2022-12-12 10:21:37 -08:00
Allan Jude f900279e6d
Restrict visibility of per-dataset kstats inside FreeBSD jails
When inside a jail, visibility on datasets not "jailed" to the
jail is restricted. However, it was possible to enumerate all
datasets in the pool by looking at the kstats sysctl MIB.

Only the kstats corresponding to datasets that the user has
visibility on are accessible now.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Closes #14254
2022-12-09 11:04:29 -08:00
Serapheim Dimitropoulos 7bf4c97a36
Bypass metaslab throttle for removal allocations
Context:
We recently had a scenario where a customer with 2x10TB disks at 95+%
fragmentation and capacity, wanted to migrate their disks to a 2x20TB
setup. So they added the 2 new disks and submitted the removal of the
first 10TB disk.  The removal took a lot more than expected (order of
more than a week to 2 weeks vs a couple of days) and once it was done it
generated a huge indirect mappign table in RAM (~16GB vs expected ~1GB).

Root-Cause:
The removal code calls `metaslab_alloc_dva()` to allocate a new block
for each evacuating block in the removing device and it tries to batch
them into 16MB segments. If it can't find such a segment it tries for
8MBs, 4MBs, all the way down to 512 bytes.

In our scenario what would happen is that `metaslab_alloc_dva()` from
the removal thread pick the new devices initially but wouldn't allocate
from them because of throttling in their metaslab allocation queue's
depth (see `metaslab_group_allocatable()`) as these devices are new and
favored for most types of allocations because of their free space. So
then the removal thread would look at the old fragmented disk for
allocations and wouldn't find any contiguous space and finally retry
with a smaller allocation size until it would to the low KB range. This
caused a lot of small mappings to be generated blowing up the size of
the indirect table. It also wasted a lot of CPU while the removal was
active making everything slow.

This patch:
Make all allocations coming from the device removal thread bypass the
throttle checks. These allocations are not even counted in the metaslab
allocation queues anyway so why check them?

Side-Fix:
Allocations with METASLAB_DONT_THROTTLE in their flags would not be
accounted at the throttle queues but they'd still abide by the
throttling rules which seems wrong. This patch fixes this by checking
for that flag in `metaslab_group_allocatable()`. I did a quick check to
see where else this flag is used and it doesn't seem like this change
would cause issues.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #14159
2022-12-09 10:48:33 -08:00
Richard Yao 242a5b748c Fix dereference after null check in enqueue_range
If the bp is NULL, we have a hole. However, when we build with
assertions, we will dereference bp when `blkid == DMU_SPILL_BLKID`. When
this happens on a hole, we will have a NULL pointer dereference.

Reported-by: Coverity (CID-1524670)
Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14264
2022-12-08 14:15:21 -08:00
Richard Yao f1100863f7 Linux: Cleanup unnecessary NULL check in __vdev_disk_physio()
zio is never NULL when given to the vdev. Coverity complained saying:

"Either the check against null is unnecessary, or there may be a null
pointer dereference."

Reported-by: Coverity (CID-1466174)
Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14263
2022-12-08 13:52:47 -08:00
Richard Yao 56c6f293c0 Remove duplicate statically allocated variable
dsl_dataset_snapshot_sync_impl() declares `static zil_header_t zero_zil
__maybe_unused;`, but this is also declared globally. This wastes
memory.

CodeQL's cpp/local-variable-hides-global-variable check caught this.

Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14263
2022-12-08 13:52:42 -08:00
Richard Yao 59493b63c1
Micro-optimize fletcher4 calculations
When processing abds, we execute 1 `kfpu_begin()`/`kfpu_end()` pair on
every page in the abd. This is wasteful and slows down checksum
performance versus what the benchmark claimed. We correct this by moving
those calls to the init and fini functions.

Also, we always check the buffer length against 0 before calling the
non-scalar checksum functions. This means that we do not need to execute
the loop condition for the first loop iteration. That allows us to
micro-optimize the checksum calculations by switching to do-while loops.

Note that we do not apply that micro-optimization to the scalar
implementation because there is no check in
`fletcher_4_incremental_native()`/`fletcher_4_incremental_byteswap()`
against 0 sized buffers being passed.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14247
2022-12-05 11:00:34 -08:00
Richard Yao 7b9a423076
FreeBSD: zfs_register_callbacks() must implement error check correctly
I read the following article and noticed a couple of ZFS bugs mentioned:

https://pvs-studio.com/en/blog/posts/cpp/0377/

I decided to search for them in the modern OpenZFS codebase and then
found one that matched the description of the first one:

V593 Consider reviewing the expression of the 'A = B != C' kind. The
expression is calculated as following: 'A = (B != C)'. zfs_vfsops.c 498

The consequence of this is that the error value is replaced with `1`
when there is an error. When there is no error, 0 is correctly passed.
This is a very minor issue that is unlikely to cause any real problems.

The incorrect error code would either be returned to the mount command
on a failure or any of `zfs receive`, `zfs recv`, `zfs rollback` or `zfs
upgrade`.

The second one has already been fixed.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14261
2022-12-05 10:16:50 -08:00
George Wilson ffd2e15d65
zio can deadlock during device removal
When doing a device removal on a pool with gang blocks, the zio pipeline
can deadlock when trying to free blocks from a device which is being
removed with a stack similar to this:

 0xffff8ab9a13a1740 UNINTERRUPTIBLE       4
                   __schedule+0x2e5
                   __schedule+0x2e5
                   schedule+0x33
                   schedule_preempt_disabled+0xe
                   __mutex_lock.isra.12+0x2a7
                   __mutex_lock.isra.12+0x2a7
                   __mutex_lock_slowpath+0x13
                   mutex_lock+0x2c
                   free_from_removing_vdev+0x61
                   metaslab_free_impl+0xd6
                   metaslab_free_dva+0x5e
                   metaslab_free+0x196
                   zio_free_sync+0xe4
                   zio_free_gang+0x38
                   zio_gang_tree_issue+0x42
                   zio_gang_tree_issue+0xa2
                   zio_gang_issue+0x6d
                   zio_execute+0x94
                   zio_execute+0x94
                   taskq_thread+0x23b
                   kthread+0x120
                   ret_from_fork+0x1f

Since there are gang blocks we have to read the gang members as part of
the free. This can be seen with a zio dependency tree that looks like
this:

sdb> echo 0xffff900c24f8a700 | zio -rc | zio
ADDRESS                       TYPE  STAGE            WAITER
0xffff900c24f8a700            NULL  CHECKSUM_VERIFY  0xffff900ddfd31740
0xffff900c24f8c920            FREE  GANG_ASSEMBLE    -
0xffff900d93d435a0            READ  DONE

In the illustration above we are processing frees but because of gang
block we have to read the constituents blocks. Once we finish the READ
in the zio pipeline we will execute the parent. In this case the parent
is a FREE but the zio taskq is a READ and we continue to process the
pipeline leading to the stack above. In the stack above, we are blocked
waiting for the svr_lock so as a result a READ interrupt taskq thread
is now consumed. Eventually, all of the READ taskq threads end up
blocked and we're unable to complete any read requests.

In zio_notify_parent there is an optimization to continue to use
the taskq thread to exectue the parent's pipeline. To resolve the
deadlock above, we only allow this optimization if the parent's
zio type matches the child which just completed.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: George Wilson <gwilson@delphix.com>
External-issue: DLPX-80130
Closes #14236
2022-12-02 17:46:29 -08:00
George Wilson d7cf06a25d
nopwrites on dmu_sync-ed blocks can result in a panic
After a device has been removed, any nopwrites for blocks on that
indirect vdev should be ignored and a new block should be allocated. The
original code attempted to handle this but used the wrong block pointer
when checking for indirect vdevs and failed to check all DVAs.

This change corrects both of these issues and modifies the test case
to ensure that it properly tests nopwrites with device removal.

Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Wilson <gwilson@delphix.com>
Closes #14235
2022-12-02 17:45:33 -08:00
Rob Wing 7a75f74cec Bump checksum error counter before reporting to ZED
The checksum error counter is incremented after reporting to ZED. This
leads ZED to receiving a checksum error report with 0 checksum errors.

To avoid this, bump the checksum error counter before reporting to ZED.

Sponsored-by: Seagate Technology LLC
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Wing <rob.wing@klarasystems.com>
Closes #14190
2022-12-02 17:42:22 -08:00
szubersk fe975048da Fix Clang 15 compilation errors
- Clang 15 doesn't support `-fno-ipa-sra` anymore. Do a separate
  check for `-fno-ipa-sra` support by $KERNEL_CC.

- Don't enable `-mgeneral-regs-only` for certain module files.
  Fix #13260

- Scope `GCC diagnostic ignored` statements to GCC only. Clang
  doesn't need them to compile the code.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: szubersk <szuberskidamian@gmail.com>
Closes #13260
Closes #14150
2022-11-30 13:46:26 -08:00
szubersk 3c1e1933b6 Fix GCC 12 compilation errors
Squelch false positives reported by GCC 12 with UBSan.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: szubersk <szuberskidamian@gmail.com>
Closes #14150
2022-11-30 13:45:53 -08:00