Commit Graph

630 Commits

Author SHA1 Message Date
Rob Norris
88aab1d2d0 linux/zvol_os: fix SET_ERROR with negative return codes
SET_ERROR is our facility for tracking errors internally. The negation
is to match the what the kernel expects from us. Thus, the negation
should happen outside of the SET_ERROR.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16364
2024-08-06 12:07:31 -07:00
Alexander Motin
d4b5517ef9
Linux: Report reclaimable memory to kernel as such (#16385)
Linux provides SLAB_RECLAIM_ACCOUNT and __GFP_RECLAIMABLE flags to
mark memory allocations that can be freed via shinker calls.  It
should allow kernel to tune and group such allocations for lower
memory fragmentation and better reclamation under pressure.

This patch marks as reclaimable most of ARC memory, directly
evictable via ZFS shrinker, plus also dnode/znode/sa memory,
indirectly evictable via kernel's superblock shrinker.

Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Allan Jude <allan@klarasystems.com>
2024-07-30 11:40:47 -07:00
Alexander Motin
55427add3c
Several improvements to ARC shrinking (#16197)
- When receiving memory pressure signal from OS be more strict
trying to free some memory.  Otherwise kernel may come again and
request much more.  Return as result how much arc_c was actually
reduced due to this request, that may be less than requested.
 - On Linux when receiving direct reclaim from some file system
(that may be ZFS) instead of ignoring request completely, just
shrink the ARC, but do not wait for eviction.  Waiting there may
cause deadlock.  Ignoring it as before may put extra pressure on
other caches and/or swap, and cause OOM if nothing help.  While
not waiting may result in more ARC evicted later, and may be too
late if OOM killer activate right now, but I hope it to be better
than doing nothing at all.
 - On Linux set arc_no_grow before waiting for reclaim, not after,
or it may grow back while we are waiting.
 - On Linux add new parameter zfs_arc_shrinker_seeks to balance
ARC eviction cost, relative to page cache and other subsystems.
 - Slightly update Linux arc_set_sys_free() math for new kernels.

Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Reviewed-by: Rob Norris <rob.norris@klarasystems.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
2024-07-25 10:31:14 -07:00
Jason Lee
41902c8e6d
Use kmap_local_page instead of kmap_atomic (#16329)
Changed zfs_k(un)map_atomic to zfs_k(un)map_local

Signed-off-by: Jason Lee <jasonlee@lanl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
2024-07-16 17:27:29 -07:00
Rob Norris
7ca7bb7fd7 Linux 5.16: use bdev_nr_bytes() to get device capacity
This helper was introduced long ago, in 5.16. Since 6.10, bd_inode no
longer exists, but the helper has been updated, so detect it and use it
in all versions where it is available.

Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
2024-07-15 17:10:06 -07:00
Rob Norris
e951dba48a Linux 6.10: work harder to avoid kmem_cache_alloc reuse
Linux 6.10 change kmem_cache_alloc to be a macro, rather than a
function, such that the old #undef for it in spl-kmem-cache.c would
remove its definition completely, breaking the build.

This inverts the model used before. Rather than always defining the
kmem_cache_* macro, then undefining then inside spl-kmem-cache.c,
instead we make a special tag to indicate we're currently inside
spl-kmem-cache.c, and not defining those in macros in the first place,
so we can use the kernel-supplied kmem_cache_* functions to implement
spl_kmem_cache_*, as we expect.

For all other callers, we create the macros as normal and remove access
to the kernel's own conflicting names.

Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
2024-07-15 17:10:02 -07:00
Rob Norris
b409892ae5 Linux 6.10: rework queue limits setup
Linux has started moving to a model where instead of applying block
queue limits through individual modification functions, a complete
limits structure is built up and applied atomically, either when the
block device or open, or some time afterwards. As of 6.10 this
transition appears only partly completed.

This commit matches that model within OpenZFS in a way that should work
for past and future kernels. We set up a queue limits structure with any
limits that have had their modification functions removed. For newer
kernels that can have limits applied at block device open
(HAVE_BLK_ALLOC_DISK_2ARG), we have a conversion function to turn the
OpenZFS queue limits structure into Linux's queue_limits structure,
which can then be passed in. For older kernels, we provide an
application function that just calls the old functions for each limit in
the structure.

Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
2024-07-15 17:09:55 -07:00
Mark Johnston
4367312760
zvol: Fix suspend lock leaks (#16270)
In several functions, we use a flag variable to track whether
zv_suspend_lock is held.  This flag was not getting reset in a
particular case where we need to retry the underlying operation,
resulting in a lock leak.  Make sure to update the flag where necessary.

Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
2024-07-10 14:27:44 -07:00
Tony Hutter
49f3ce3385
Linux 6.9: Call add_disk() from workqueue to fix zfs_allow_010_pos (#16282)
The 6.9 kernel behaves differently in how it releases block devices.  In
the common case it will async release the device only after the return
to userspace.  This is different from the 6.8 and older kernels which
release the block devices synchronously.  To get around this, call
add_disk() from a workqueue so that the kernel uses a different
codepath to release our zvols in the way we expect.  This stops
zfs_allow_010_pos from hanging.

Fixes: #16089

Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Rob Norris <rob.norris@klarasystems.com>
2024-06-28 09:52:03 -07:00
Pawel Jakub Dawidek
01c8efdd59
Simplify issig().
We always call it twice with JUSTLOOKING and then FORREAL.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Pawel Jakub Dawidek <pawel@dawidek.net>
Closes #16225
2024-05-29 10:49:11 -07:00
Rob Norris
3c941d1818 zdb/ztest: send dbgmsg output to stderr
And, make the output fd an arg to zfs_dbgmsg_print(). This is a change
in behaviour, but keeps it consistent with where crash traces go, and
it's easy to argue this is what we want anyway; this is information
about the task, not the actual output of the task.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16181
2024-05-14 09:49:00 -07:00
Rob Norris
fa99d9cd9c zfs_dbgmsg_print: make FreeBSD and Linux consistent
FreeBSD was using fprintf(), which might not be signal-safe. Meanwhile,
Linux's locking did not cover the header output. This two quirks are
unrelated, but both have the same response: be like the other one. So
with this commit, both functions are the same except for the names of
their lock and list variables.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16181
2024-05-14 09:48:56 -07:00
Brian Behlendorf
abec7dcd30
Linux: disable lockdep for a couple of locks
When running a debug kernel with lockdep enabled there
are several locks which report false positives.  Set
MUTEX_NOLOCKDEP/RW_NOLOCKDEP to disable these warnings.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #16188
2024-05-13 15:12:07 -07:00
chenqiuhao1997
41ae864b69
Replace P2ALIGN with P2ALIGN_TYPED and delete P2ALIGN.
In P2ALIGN, the result would be incorrect when align is unsigned
integer and x is larger than max value of the type of align.
In that case, -(align) would be a positive integer, which means
high bits would be zero and finally stay zero after '&' when
align is converted to a larger integer type.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Youzhong Yang <yyang@mathworks.com>
Signed-off-by: Qiuhao Chen <chenqiuhao1997@gmail.com>
Closes #15940
2024-05-10 08:47:21 -07:00
Daniel Perry
2dff7527d4
Replace usage of schedule_timeout with schedule_timeout_interruptible (#16150)
This commit replaces current usages of schedule_timeout() with
schedule_timeout_interruptible() in code paths that expect the running
task to sleep for a short period of time. When schedule_timeout() is
called without previously calling set_current_state(), the running
task never sleeps because the task state remains in TASK_RUNNING.

By calling schedule_timeout_interruptible() to set the task state to
TASK_INTERRUPTIBLE before calling schedule_timeout() we achieve the
intended/desired behavior of putting the task to sleep for the
specified timeout.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Daniel Perry <dtperry@amazon.com>
Closes #16150
2024-05-09 07:30:28 -07:00
Rob N
8f1b7a6fa6
vdev_disk: disable flushes if device does not support it
If the underlying device doesn't have a write-back cache, the kernel
will just return a successful response. This doesn't hurt anything, but
it's extra work on the IO taskqs that are unnecessary. So, detect this
when we open the device for the first time.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16148
2024-05-02 15:18:35 -07:00
Alan Somers
21bc066ece
Fix updating the zvol_htable when renaming a zvol
When renaming a zvol, insert it into zvol_htable using the new name, not
the old name.  Otherwise some operations won't work.  For example,
"zfs set volsize" while the zvol is open.

Sponsored by:	Axcient
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alek Pinchuk <apinchuk@axcient.com>
Signed-off-by:	Alan Somers <asomers@FreeBSD.org>
Closes #16127
Closes #16128
2024-04-25 14:24:52 -07:00
Rob N
f4f156157d
abd_iter_page: rework to handle multipage scatterlists
Previously, abd_iter_page() would assume that every scatterlist would
contain a single page (compound or no), because that's all we ever
create in abd_alloc_chunks(). However, scatterlists can contain multiple
pages of arbitrary provenance, and if we get one of those, we'd get all
the math wrong.

This reworks things to handle multiple pages in a scatterlist, by
properly finding the right page within it for the given offset, and
understanding better where the end of the page is and not crossing it.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reported-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16108
2024-04-19 16:41:31 -07:00
Rob Norris
d7605ae77b zio: rename ZIO_TYPE_IOCTL to ZIO_TYPE_FLUSH
The only possible ioctl is a flush, and any other kind of meta-operation
introduced in the future is likely to have different semantics (much
like trim did). So, lets just call it what it is.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16064
2024-04-11 17:17:23 -07:00
Rob Norris
c9c838aa1f zio: remove io_cmd and DKIOCFLUSHWRITECACHE
There's no other options, so we can just always assume its a flush.

Includes some light refactoring where a switch statement was doing
control flow that no longer works.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16064
2024-04-11 17:17:11 -07:00
Rob Norris
1bf649cb0a vdev_disk: fix alignment check when buffer has non-zero starting offset
If a linear buffer spans multiple pages, and the first page has a
non-zero starting offset, the checker would not include the offset, and
so would think there was an alignment gap at the end of the first page,
rather than at the start.

That is, for a 16K buffer spread across five pages with an initial 512B
offset:

    [.XXXXXXX][XXXXXXXX][XXXXXXXX][XXXXXXXX][XXXXXXX.]

It would be interpreted as:

    [XXXXXXX.][XXXXXXXX]...

And be rejected as misaligned.

Since it's already a linear ABD, the "linearising" copy would just reuse
the buffer as-is, and the second check would failing, tripping the
VERIFY in vdev_disk_io_rw().

This commit fixes all this by including the offset in the check for
end-of-page alignment.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16076
2024-04-11 14:43:27 -07:00
Rob Norris
bc27c49404 tests: add test for vdev_disk page alignment check
This provides a test driver and a set of test vectors for the page
alignment check callback function vdev_disk_check_pages_cb().

Because there's no good facility for exposing this function to a
userspace test right now, for now I'm just duplicating the function and
adding commentary to remind people to keep them in sync.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16076
2024-04-11 14:42:46 -07:00
Rob N
ba9f587a77
vdev_disk: ensure trim errors are returned immediately
After 06e25f9c4, the discard issuing code was organised such that if
requesting an async discard or secure erase failed before the IO was
issued (that is, calling __blkdev_issue_discard() returned an error),
the failed zio would never be executed, resulting in txg_sync hanging
forever waiting for IO to finish.

This commit fixes that by immediately executing a failed zio on error.
To handle the successful synchronous op case, we fake an async op by,
when not using an asynchronous submission method, queuing the successful
result zio as part of the discard handler.

Since it was hard to understand the differences between discard and
secure erase, and sync and async, across different kernel versions, I've
commented and reorganised the code a bit to try and make everything more
contained and linear.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16070
2024-04-08 11:50:24 -07:00
Rob N
03987f71e3
zvol_os: fix compile with blk-mq on Linux 4.x
99741bde5 accesses a cached blk-mq hardware context through the mq_hctx
field of struct request. However, this field did not exist until 5.0.
Before that, the private function blk_mq_map_queue() was used to dig it
out of broader queue context. This commit detects this situation, and
handles it with a poor-man's simulation of that function.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16069
2024-04-08 11:38:49 -07:00
Rob N
c13400c9a2
zvol_os: fix build on Linux <3.13
99741bde5 introduced zvol_num_taskqs, but put it behind the HAVE_BLK_MQ
define, preventing builds on versions of Linux that don't have it
(<3.13, incl EL7).

Nothing about it seems dependent on blk-mq, so this just moves it out
from behind that define and so fixes the build.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16062
2024-04-08 10:13:27 -07:00
Ameer Hamza
99741bde59
zvol: use multiple taskq
Currently, zvol uses a single taskq, resulting in throughput bottleneck
under heavy load due to lock contention on the single taskq. This patch
addresses the performance bottleneck under heavy load conditions by
utilizing multiple taskqs, thus mitigating lock contention. The number
of taskqs scale dynamically based on the available CPUs in the system,
as illustrated below:

                taskq   total
cpus    taskqs  threads threads
------- ------- ------- -------
1       1       32       32
2       1       32       32
4       1       32       32
8       2       16       32
16      3       11       33
32      5       7        35
64      8       8        64
128     11      12       132
256     16      16       256

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes #15992
2024-04-03 18:21:25 -07:00
Rob Norris
6097a7ba8b Linux 6.9 compat: blk_alloc_disk() now takes two args
There's an extra nullable arg for queue limits. Detect it, and set it to
NULL. Similar change for blk_mq_alloc_disk(), now three args, same
treatment.

Error return now has error encoded in the return, so detect with
IS_ERR() and explicitly NULL our own return.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Closes #16027
Closes #16033
2024-04-03 15:29:39 -07:00
Rob Norris
e3120f73d0 Linux 6.9 compat: bdev handles are now struct file
bdev_open_by_path() is replaced by bdev_file_open_by_path(), which
returns a plain old struct file*. Release function is gone entirely; the
regular file release function fput() will take care of the bdev
specifics.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Closes #16027
Closes #16033
2024-04-03 15:29:33 -07:00
Rob N
917ff75e95
vdev_disk: don't touch vbio after its handed off to the kernel
After IO is unplugged, it may complete immediately and vbio_completion
be called on interrupt context. That may interrupt or deschedule our
task. If its the last bio, the vbio will be freed. Then, we get
rescheduled, and try to write to freed memory through vbio->.

This patch just removes the the cleanup, and the corresponding assert.
These were leftovers from a previous iteration of vbio_submit() and were
always "belt and suspenders" ops anyway, never strictly required.

Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc
Reported-by: Rich Ercolani <rincebrain@gmail.com>
Reviewed-by: Laurențiu Nicola <lnicola@dend.ro>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #16045
Closes #16050
Closes #16049
2024-04-03 15:17:07 -07:00
Rob N
a9a4290173
xdr: header cleanup
#16047 notes that include/os/freebsd/spl/rpc/xdr.h carried an
(apparently) incompatible license. While looking into it, it seems that
this file is actually unnecessary these days - FreeBSD's kernel XDR has
XDR_CONTROL, xdrmem_control and XDR_GET_BYTES_AVAIL, while userspace has
XDR_CONTROL and xdrmem_control, and our implementation of
XDR_GET_BYTES_AVAIL for libspl works nicely with it. So this removes
that file outright.

To keep the includes in nvpair.c tidy, I've made a few small adjustments
to the Linux headers. By definition, rpc/types.h provides bool_t and is
included before rpc/xdr.h, so I've created rpc/types.h for Linux. This
isn't necessary for userspace; both FreeBSD native and tirpc on Linux
already have these headers set up correctly.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Closes #16047 
Closes #16051
2024-04-03 15:13:27 -07:00
Rob N
cfb96c772b
vdev_disk: clean up spa/bdev mode conversion
43e8f6e37 introduced a subtle API misuse, in that it passed the output
from vdev_bdev_mode() back into itself. Fortunately, the
SPA_MODE_(READ|WRITE) bit values exactly map to the FMODE_(READ|WRITE) &
BLK_OPEN_(READ|WRITE) bit values, so it didn't result in a bug, but it
was hard to read and understand, so I cleaned it up.

In doing so, I noticed that the only call to vdev_bdev_mode() without
the "exclusive" flag set was in that misuse, and actually, we never do a
non-exclusive blkdev_get_by_path(). So I've just made exclusive be
always-on.


Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #15995
2024-03-29 14:51:33 -07:00
Fabian-Gruenbichler
c0aab8b8f9
zvols: prevent overflow of minor device numbers
currently, the linux kernel allows 2^20 minor devices per major device
number.  ZFS reserves blocks of 2^4 minors per zvol: 1 for the zvol
itself, the other 15 for the first partitions of that zvol. as a result,
only 2^16 such blocks are available for use.

there are no checks in place to avoid overflowing into the major device
number when more than 2^16 zvols are allocated (with volmode=dev or
default). instead of ignoring this limit, which comes with all sorts of
weird knock-on effects, detect this situation and simply fail allocating
the zvol block device early on.

without this safeguard, the kernel will reject the attempt to create an
already existing block device, but ZFS doesn't handle this error and
gets confused about which zvol occupies which minor slot, potentially
resulting in kernel NULL derefs and other issues later on.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Closes #16006
2024-03-29 14:37:40 -07:00
Rob Norris
c6be6ce175 abd_iter_page: don't use compound heads on Linux <4.5
Before 4.5 (specifically, torvalds/linux@ddc58f2), head and tail pages
in a compound page were refcounted separately. This means that using the
head page without taking a reference to it could see it cleaned up later
before we're finished with it. Specifically, bio_add_page() would take a
reference, and drop its reference after the bio completion callback
returns.

If the zio is executed immediately from the completion callback, this is
usually ok, as any data is referenced through the tail page referenced
by the ABD, and so becomes "live" that way. If there's a delay in zio
execution (high load, error injection), then the head page can be freed,
along with any dirty flags or other indicators that the underlying
memory is used. Later, when the zio completes and that memory is
accessed, its either unmapped and an unhandled fault takes down the
entire system, or it is mapped and we end up messing around in someone
else's memory. Both of these are very bad.

The solution on these older kernels is to take a reference to the head
page when we use it, and release it when we're done. There's not really
a sensible way under our current structure to do this; the "best" would
be to keep a list of head page references in the ABD, and release them
when the ABD is freed.

Since this additional overhead is totally unnecessary on 4.5+, where
head and tail pages share refcounts, I've opted to simply not use the
compound head in ABD page iteration there. This is theoretically less
efficient (though cleaning up head page references would add overhead),
but its safe, and we still get the other benefits of not mapping pages
before adding them to a bio and not mis-splitting pages.

There doesn't appear to be an obvious symbol name or config option we
can match on to discover this behaviour in configure (and the mm/page
APIs have changed a lot since then anyway), so I've gone with a simple
version check.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:51:54 -07:00
Rob Norris
72fd834c47 vdev_disk: use bio_chain() to submit multiple BIOs
Simplifies our code a lot, so we don't have to wait for each and
reassemble them.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:51:47 -07:00
Rob Norris
df2169d141 vdev_disk: add module parameter to select BIO submission method
This makes the submission method selectable at module load time via the
`zfs_vdev_disk_classic` parameter, allowing this change to be backported
to 2.2 safely, and disabled in favour of the "classic" submission method
if new problems come up.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:51:30 -07:00
Rob Norris
06a196020e vdev_disk: rewrite BIO filling machinery to avoid split pages
This commit tackles a number of issues in the way BIOs (`struct bio`)
are constructed for submission to the Linux block layer.

The kernel has a hard upper limit on the number of pages/segments that
can be added to a BIO, as well as a separate limit for each device
(related to its queue depth and other scheduling characteristics).

ZFS counts the number of memory pages in the request ABD
(`abd_nr_pages_off()`, and then uses that as the number of segments to
put into the BIO, up to the hard upper limit. If it requires more than
the limit, it will create multiple BIOs.

Leaving aside the fact that page count method is wrong (see below), not
limiting to the device segment max means that the device driver will
need to split the BIO in half. This is alone is not necessarily a
problem, but it interacts with another issue to cause a much larger
problem.

The kernel function to add a segment to a BIO (`bio_add_page()`) takes a
`struct page` pointer, and offset+len within it. `struct page` can
represent a run of contiguous memory pages (known as a "compound page").
In can be of arbitrary length.

The ZFS functions that count ABD pages and load them into the BIO
(`abd_nr_pages_off()`, `bio_map()` and `abd_bio_map_off()`) will never
consider a page to be more than `PAGE_SIZE` (4K), even if the `struct
page` is for multiple pages. In this case, it will load the same `struct
page` into the BIO multiple times, with the offset adjusted each time.

With a sufficiently large ABD, this can easily lead to the BIO being
entirely filled much earlier than it could have been. This is also
further contributes to the problem caused by the incorrect segment limit
calculation, as its much easier to go past the device limit, and so
require a split.

Again, this is not a problem on its own.

The logic for "never submit more than `PAGE_SIZE`" is actually a little
more subtle. It will actually never submit a buffer that crosses a 4K
page boundary.

In practice, this is fine, as most ABDs are scattered, that is a list of
complete 4K pages, and so are loaded in as such.

Linear ABDs are typically allocated from slabs, and for small sizes they
are frequently not aligned to page boundaries. For example, a 12K
allocation can span four pages, eg:

     -- 4K -- -- 4K -- -- 4K -- -- 4K --
    |        |        |        |        |
          :## ######## ######## ######:    [1K, 4K, 4K, 3K]

Such an allocation would be loaded into a BIO as you see:

    [1K, 4K, 4K, 3K]

This tends not to be a problem in practice, because even if the BIO were
filled and needed to be split, each half would still have either a start
or end aligned to the logical block size of the device (assuming 4K at
least).

---

In ideal circumstances, these shortcomings don't cause any particular
problems. Its when they start to interact with other ZFS features that
things get interesting.

Aggregation will create a "gang" ABD, which is simply a list of other
ABDs. Iterating over a gang ABD is just iterating over each ABD within
it in turn.

Because the segments are simply loaded in order, we can end up with
uneven segments either side of the "gap" between the two ABDs. For
example, two 12K ABDs might be aggregated and then loaded as:

    [1K, 4K, 4K, 3K, 2K, 4K, 4K, 2K]

Should a split occur, each individual BIO can end up either having an
start or end offset that is not aligned to the logical block size, which
some drivers (eg SCSI) will reject. However, this tends not to happen
because the default aggregation limit usually keeps the BIO small enough
to not require more than one split, and most pages are actually full 4K
pages, so hitting an uneven gap is very rare anyway.

If the pool is under particular memory pressure, then an IO can be
broken down into a "gang block", a 512-byte block composed of a header
and up to three block pointers. Each points to a fragment of the
original write, or in turn, another gang block, breaking the original
data up over and over until space can be found in the pool for each of
them.

Each gang header is a separate 512-byte memory allocation from a slab,
that needs to be written down to disk. When the gang header is added to
the BIO, its a single 512-byte segment.

Pulling all this together, consider a large aggregated write of gang
blocks. This results a BIO containing lots of 512-byte segments. Given
our tendency to overfill the BIO, a split is likely, and most possible
split points will yield a pair of BIOs that are misaligned. Drivers that
care, like the SCSI driver, will reject them.

---

This commit is a substantial refactor and rewrite of much of `vdev_disk`
to sort all this out.

`vdev_bio_max_segs()` now returns the ideal maximum size for the device,
if available. There's also a tuneable `zfs_vdev_disk_max_segs` to
override this, to assist with testing.

We scan the ABD up front to count the number of pages within it, and to
confirm that if we submitted all those pages to one or more BIOs, it
could be split at any point with creating a misaligned BIO.  If the
pages in the BIO are not usable (as in any of the above situations), the
ABD is linearised, and then checked again. This is the same technique
used in `vdev_geom` on FreeBSD, adjusted for Linux's variable page size
and allocator quirks.

`vbio_t` is a cleanup and enhancement of the old `dio_request_t`. The
idea is simply that it can hold all the state needed to create, submit
and return multiple BIOs, including all the refcounts, the ABD copy if
it was needed, and so on. Apart from what I hope is a clearer interface,
the major difference is that because we know how many BIOs we'll need up
front, we don't need the old overflow logic that would grow the BIO
array, throw away all the old work and restart. We can get it right from
the start.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:51:14 -07:00
Rob Norris
c4a13ba483 vdev_disk: make read/write IO function configurable
This is just setting up for the next couple of commits, which will add a
new IO function and a parameter to select it.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:51:04 -07:00
Rob Norris
867178ae1d vdev_disk: reorganise vdev_disk_io_start
Light reshuffle to make it a bit more linear to read and get rid of a
bunch of args that aren't needed in all cases.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:50:56 -07:00
Rob Norris
f3b85d706b vdev_disk: rename existing functions to vdev_classic_*
This is just renaming the existing functions we're about to replace and
grouping them together to make the next commits easier to follow.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:50:47 -07:00
Rob Norris
390b448726 abd: add page iterator
The regular ABD iterators yield data buffers, so they have to map and
unmap pages into kernel memory. If the caller only wants to count
chunks, or can use page pointers directly, then the map/unmap is just
unnecessary overhead.

This adds adb_iterate_page_func, which yields unmapped struct page
instead.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15533
Closes #15588
2024-03-25 16:50:35 -07:00
Robert Evans
102b468b5e
Fix corruption caused by mmap flushing problems
1) Make mmap flushes synchronous. Linux may skip flushing dirty pages
   already in writeback unless data-integrity sync is requested.

2) Change zfs_putpage to use TXG_WAIT. Otherwise dirty pages may be
   skipped due to DMU pushing back on TX assign.

3) Add missing mmap flush when doing block cloning.

4) While here, pass errors from putpage to writepage/writepages.

This change fixes corruption edge cases, but unfortunately adds
synchronous ZIL flushes for dirty mmap pages to llseek and bclone
operations. It may be possible to avoid these sync writes later
but would need more tricky refactoring of the writeback code.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Robert Evans <evansr@google.com>
Closes #15933 
Closes #16019
2024-03-25 14:56:49 -07:00
Rob N
ef08a4d406
Linux 6.8 compat: use splice_copy_file_range() for fallback
Linux 6.8 removes generic_copy_file_range(), which had been reduced to a
simple wrapper around splice_copy_file_range(). Detect that function
directly and use it if generic_ is not available.

Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #15930 
Closes #15931
2024-03-20 16:46:15 -07:00
Quartz
5600dff0ef
Fixed parameter passing error when calling zfs_acl_chmod
Follow up to 99495ba6ab which
accidentally introduce this regression.

Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Quartz <yyhran@163.com>
Closes #15907
2024-02-26 11:41:44 -08:00
Alexander Motin
e0bd8118d0
Linux: Cleanup taskq threads spawn/exit
This changes taskq_thread_should_stop() to limit maximum exit rate
for idle threads to one per 5 seconds.  I believe the previous one
was broken, not allowing any thread exits for tasks arriving more
than one at a time and so completing while others are running.

Also while there:
 - Remove taskq_thread_spawn() calls on task allocation errors.
 - Remove extra taskq_thread_should_stop() call.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rich Ercolani <rincebrain@gmail.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15873
2024-02-13 11:15:16 -08:00
Brian Behlendorf
6dccdf501e
BRT: Fix FICLONE/FICLONERANGE shortened copy
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 #15728
Closes #15842
2024-02-05 16:44:45 -08:00
Umer Saleem
06e25f9c4b
Improve performance for zpool trim on linux
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
2024-02-02 11:51:51 -08:00
Rob Norris
7692d86de4 Linux 6.8 compat: replace MAX_ORDER define
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
2024-01-29 11:36:07 -08:00
Rob Norris
84980ee0e6 Linux 6.8 compat: implement strlcpy fallback
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
2024-01-29 11:36:07 -08:00
Rob Norris
386d6a7533 Linux 6.8 compat: update for new bdev access functions
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
2024-01-29 11:36:07 -08:00
Tino Reichardt
e3d3d772de
linux spl: fix typo in top comment of spl-condvar.c
Credential Implementation -> Condition Variables Implementation

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tino Reichardt <milky-zfs@mcmilk.de>
Closes #15782
2024-01-17 09:05:12 -08:00
Rob N
f0bf7a247d
Linux 6.7 compat: zfs_setattr fix atime update
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 #15762
Closes #15773
2024-01-16 14:01:17 -08:00
youzhongyang
29ea6faf8f
Make spl_kmem_cache size check consistent
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
2024-01-16 13:30:58 -08:00
Mark Johnston
d8b2686603 Linux: Defer loading the object set in zfs_setattr()
We need to wait until after having done a zfs_enter() to load some
fields from the zfsvfs structure.  Otherwise a use-after-free is
possible in the face of a concurrent rollback.

Other functions in this file are careful to avoid this bug, I believe
this is the only instance.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Closes #15752
2024-01-12 11:51:53 -08:00
Brian Behlendorf
233d34e47e
Linux 6.5 compat: check BLK_OPEN_EXCL is defined
On some systems we already have blkdev_get_by_path() with 4 args
but still the old FMODE_EXCL and not BLK_OPEN_EXCL defined.
The vdev_bdev_mode() function was added to handle this case
but there was no generic way to specify exclusive access.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #15692
2023-12-21 11:22:56 -08:00
Rob Norris
957dc1037a Linux 6.7 compat: rework shrinker setup for heap allocations
6.7 changes the shrinker API such that shrinkers must be allocated
dynamically by the kernel. To accomodate this, this commit reworks
spl_register_shrinker() to do something similar against earlier kernels.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://github.com/sponsors/robn
Closes #15681
2023-12-20 11:47:55 -08:00
Rob Norris
1d324aceef Linux 6.7 compat: handle superblock shrinker member change
In 6.7 the superblock shrinker member s_shrink has changed from being an
embedded struct to a pointer. Detect this, and don't take a reference if
it already is one.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://github.com/sponsors/robn
Closes #15681
2023-12-20 11:47:50 -08:00
Rob Norris
db4fc559cc Linux 6.7 compat: use inode atime/mtime accessors
6.6 made i_ctime inaccessible; 6.7 has done the same for i_atime and
i_mtime. This extends the method used for ctime in b37f29341 to atime
and mtime as well.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://github.com/sponsors/robn
Closes #15681
2023-12-20 11:47:40 -08:00
Alexander Motin
2a27fd4111
ZIL: Assert record sizes in different places
This should make sure we have log written without overflows.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15517
2023-11-28 13:35:14 -08:00
Alexander Motin
cf33166336
ZVOL: Minor code cleanup
- Remove zsda_tx field, it is used only once.
 - Remove unneeded string lengths checks, all names are terminated.
 - Replace few explicit MAXNAMELEN usages with sizeof().
 - Change dsname from MAXNAMELEN to ZFS_MAX_DATASET_NAME_LEN, as
expected by dsl_dataset_name().  Both are 256 bytes now, but it is
better to be safe.

This should have no functional difference.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15535
2023-11-27 13:16:59 -08:00
Alexander Motin
a490875103 ZIL: Refactor TX_WRITE encryption similar to TX_CLONE_RANGE
It should be purely textual change to make the code more readable.
Should cause no functional difference.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Tom Caputi <caputit1@tcnj.edu>
Reviewed-by: Sean Eric Fagan <sef@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Edmund Nadolski <edmund.nadolski@ixsystems.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes #15543
Closes #15513
2023-11-27 09:56:30 -08:00
Alexander Motin
27d8c23c58 ZIL: Do not encrypt block pointers in lr_clone_range_t
In case of crash cloned blocks need to be claimed on pool import.
It is only possible if they (lr_bps) and their count (lr_nbps) are
not encrypted but only authenticated, similar to block pointer in
lr_write_t.  Few other fields can be and are still encrypted.

This should fix panic on ZIL claim after crash when block cloning
is actively used.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Tom Caputi <caputit1@tcnj.edu>
Reviewed-by: Sean Eric Fagan <sef@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Edmund Nadolski <edmund.nadolski@ixsystems.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes #15543
Closes #15513
2023-11-27 09:53:32 -08:00
Rich Ercolani
03e9caaec0
Add a tunable to disable BRT support.
Copy the disable parameter that FreeBSD implemented, and extend it to
work on Linux as well, until we're sure this is stable.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes #15529
2023-11-16 11:35:22 -08:00
Alexander Motin
3a8d9b8487
Linux: Reclaim unused spl_kmem_cache_reclaim
It is unused for 3 years since #10576.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15507
2023-11-10 10:34:46 -08:00
Low-power
a160c153e2
Linux: reject read/write mapping to immutable file only on VM_SHARED
Private read/write mapping can't be used to modify the mapped files, so
they will remain be immutable. Private read/write mappings are usually
used to load the data segment of executable files, rejecting them will
rendering immutable executable files to stop working.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: WHR <msl0000023508@gmail.com>
Closes #15344
2023-11-08 12:19:38 -08:00
Don Brady
5caeef02fa
RAID-Z expansion feature
This feature allows disks to be added one at a time to a RAID-Z group,
expanding its capacity incrementally.  This feature is especially useful
for small pools (typically with only one RAID-Z group), where there
isn't sufficient hardware to add capacity by adding a whole new RAID-Z
group (typically doubling the number of disks).

== Initiating expansion ==

A new device (disk) can be attached to an existing RAIDZ vdev, by
running `zpool attach POOL raidzP-N NEW_DEVICE`, e.g. `zpool attach tank
raidz2-0 sda`.  The new device will become part of the RAIDZ group.  A
"raidz expansion" will be initiated, and the new device will contribute
additional space to the RAIDZ group once the expansion completes.

The `feature@raidz_expansion` on-disk feature flag must be `enabled` to
initiate an expansion, and it remains `active` for the life of the pool.
In other words, pools with expanded RAIDZ vdevs can not be imported by
older releases of the ZFS software.

== During expansion ==

The expansion entails reading all allocated space from existing disks in
the RAIDZ group, and rewriting it to the new disks in the RAIDZ group
(including the newly added device).

The expansion progress can be monitored with `zpool status`.

Data redundancy is maintained during (and after) the expansion.  If a
disk fails while the expansion is in progress, the expansion pauses
until the health of the RAIDZ vdev is restored (e.g. by replacing the
failed disk and waiting for reconstruction to complete).

The pool remains accessible during expansion.  Following a reboot or
export/import, the expansion resumes where it left off.

== After expansion ==

When the expansion completes, the additional space is available for use,
and is reflected in the `available` zfs property (as seen in `zfs list`,
`df`, etc).

Expansion does not change the number of failures that can be tolerated
without data loss (e.g. a RAIDZ2 is still a RAIDZ2 even after
expansion).

A RAIDZ vdev can be expanded multiple times.

After the expansion completes, old blocks remain with their old
data-to-parity ratio (e.g. 5-wide RAIDZ2, has 3 data to 2 parity), but
distributed among the larger set of disks.  New blocks will be written
with the new data-to-parity ratio (e.g. a 5-wide RAIDZ2 which has been
expanded once to 6-wide, has 4 data to 2 parity).  However, the RAIDZ
vdev's "assumed parity ratio" does not change, so slightly less space
than is expected may be reported for newly-written blocks, according to
`zfs list`, `df`, `ls -s`, and similar tools.

Sponsored-by: The FreeBSD Foundation
Sponsored-by: iXsystems, Inc.
Sponsored-by: vStack
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Authored-by: Matthew Ahrens <mahrens@delphix.com>
Contributions-by: Fedor Uporov <fuporov.vstack@gmail.com>
Contributions-by: Stuart Maybee <stuart.maybee@comcast.net>
Contributions-by: Thorsten Behrens <tbehrens@outlook.com>
Contributions-by: Fmstrat <nospam@nowsci.com>
Contributions-by: Don Brady <dev.fs.zfs@gmail.com>
Signed-off-by: Don Brady <dev.fs.zfs@gmail.com>
Closes #15022
2023-11-08 10:19:41 -08:00
Umer Saleem
9198de8f10
Linux 6.6 compat: fix implicit conversion error with debug build
With Linux v6.6.0 and GCC 12, when debug build is configured,
implicit conversion error is raised while converting
'enum <anonymous>' to 'boolean_t'. Use 'B_TRUE' instead of
'true' to fix the issue.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Pavel Snajdr <snajpa@snajpa.net>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes #15489
2023-11-07 13:24:16 -08:00
Alan Somers
e36ff84c33
Update the kstat dataset_name when renaming a zvol
Add a dataset_kstats_rename function, and call it when renaming
a zvol on FreeBSD and Linux.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alan Somers <asomers@gmail.com>
Sponsored-by: Axcient
Closes #15482
Closes #15486
2023-11-07 11:34:50 -08:00
ednadolski-ix
3bd4df3841
Improve ZFS objset sync parallelism
As part of transaction group commit, dsl_pool_sync() sequentially calls
dsl_dataset_sync() for each dirty dataset, which subsequently calls
dmu_objset_sync().  dmu_objset_sync() in turn uses up to 75% of CPU
cores to run sync_dnodes_task() in taskq threads to sync the dirty
dnodes (files).

There are two problems:

1. Each ZVOL in a pool is a separate dataset/objset having a single
   dnode.  This means the objsets are synchronized serially, which
   leads to a bottleneck of ~330K blocks written per second per pool.

2. In the case of multiple dirty dnodes/files on a dataset/objset on a
   big system they will be sync'd in parallel taskq threads. However,
   it is inefficient to to use 75% of CPU cores of a big system to do
   that, because of (a) bottlenecks on a single write issue taskq, and
   (b) allocation throttling.  In addition, if not for the allocation
   throttling sorting write requests by bookmarks (logical address),
   writes for different files may reach space allocators interleaved,
   leading to unwanted fragmentation.

The solution to both problems is to always sync no more and (if
possible) no fewer dnodes at the same time than there are allocators
the pool.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Edmund Nadolski <edmund.nadolski@ixsystems.com>
Closes #15197
2023-11-06 10:38:42 -08:00
Ameer Hamza
60387facd2 zvol: Implement zvol threading as a Property
Currently, zvol threading can be switched through the zvol_request_sync
module parameter system-wide. By making it a zvol property, zvol
threading can be switched per zvol.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes #15409
2023-10-31 09:50:32 -07:00
Alexander Motin
799e09f75a
Unify arc_prune_async() code
There is no sense to have separate implementations for FreeBSD and
Linux.  Make Linux code shared as more functional and just register
FreeBSD-specific prune callback with arc_add_prune_callback() API.

Aside of code cleanup this should fix excessive pruning on FreeBSD:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=274698

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Johnston <markj@FreeBSD.org>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15456
2023-10-30 16:56:04 -07:00
Alexander Motin
c3773de168
ZIL: Cleanup sync and commit handling
ZVOL:
 - Mark all ZVOL ZIL transactions as sync.  Since ZVOLs have only
one object, it makes no sense to maintain async queue and on each
commit merge it into sync. Single sync queue is just cheaper, while
it changes nothing until actual commit request arrives.
 - Remove zsd_sync_cnt and the zil_async_to_sync() calls since we
are no longer switching between sync and async queues.

ZFS:
 - Mark write transactions as sync based only on number of sync
opens (z_sync_cnt).  We can not randomly jump between sync and
async unless we want data corruptions due to writes reordering.
 - When file first opened with O_SYNC (z_sync_cnt incremented to 1)
call zil_async_to_sync() for it to preserve correct ordering between
past and future writes.
 - Drop zfs_fsyncer_key logic.  Looks like it was an optimization
for workloads heavily intermixing async writes with tons of fsyncs.
But first it was broken 8 years ago due to Linux tsd implementation
not allowing data storage between syscalls, and second, I doubt it
is safe to switch from async to sync so often and without calling
zil_async_to_sync().

 - Rename sync argument of *_log_write() into commit, now only
signalling caller's intent to call zil_commit() soon after.  It
allows WR_COPIED optimizations without extra other meanings.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15366
2023-10-30 14:51:56 -07:00
ednadolski-ix
6a629f3234
arc_default_max on Linux should match FreeBSD
Commits 518b487 and 23bdb07 changed the default ARC size limit on
Linux systems to 1/2 of physical memory, which has become too
strict for modern systems with large amounts of RAM. This patch
changes the default limit to match that of FreeBSD, so ZFS may
have a unified value on both platforms.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Edmund Nadolski <edmund.nadolski@ixsystems.com>
Closes #15437
2023-10-26 09:13:01 -07:00
Tony Hutter
05c4710e89 Revert "zvol: Temporally disable blk-mq"
This reverts commit aefb6a2bd6.

aefb6a2bd temporally disabled blk-mq until we could fix a fix for

Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #15439
2023-10-24 14:41:25 -07:00
Tony Hutter
7c9b6fed16 zvol: Remove broken blk-mq optimization
This fix removes a dubious optimization in zfs_uiomove_bvec_rq()
that saved the iterator contents of a rq_for_each_segment().  This
optimization allowed restoring the "saved state" from a previous
rq_for_each_segment() call on the same uio so that you wouldn't
need to iterate though each bvec on every zfs_uiomove_bvec_rq() call.
However, if the kernel is manipulating the requests/bios/bvecs under
the covers between zfs_uiomove_bvec_rq() calls, then it could result
in corruption from using the "saved state".  This optimization
results in an unbootable system after installing an OS on a zvol
with blk-mq enabled.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #15351
2023-10-24 14:37:52 -07:00
Daniel Berlin
bc29124b1b
Ensure we call fput when cloning fails due to different devices.
Right now, zpl_ioctl_ficlone and zpl_ioctl_ficlonerange do not call
put on the src fd if the source and destination are on two different
devices.  This leaves the source file held open in this case.

Reviewed-by: Kay Pedersen <mail@mkwg.de>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Daniel Berlin <dberlin@dberlin.org>
Closes #15386
2023-10-10 11:04:32 -07:00
Tony Hutter
aefb6a2bd6
zvol: Temporally disable blk-mq
There was a report of zvol data loss (#15351) after enabling blk-mq on a
zvol backed with 16k physical block sized disks.  Out of an abundance of
caution, do not allow the user to enable blk-mq until we can look into
the issue.

Note that blk-mq was not enabled by default on zvols.  It was always
opt-in via the zvol_use_blk_mq module parameter.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Addresses: #15351
Closes #15378
2023-10-10 08:57:48 -07:00
Coleman Kane
7ac56b86cd Linux 6.6 compat: fsync_bdev() has been removed in favor of sync_blockdev()
In Linux commit 560e20e4bf6484a0c12f9f3c7a1aa55056948e1e, the
fsync_bdev() function was removed in favor of sync_blockdev() to do
(roughly) the same thing, given the same input. This change
conditionally attempts to call sync_blockdev() if fsync_bdev() isn't
discovered during configure.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15263
2023-09-21 18:38:40 -07:00
Coleman Kane
01d00dfa9e Linux 6.6 compat: generic_fillattr has a new u32 request_mask added at arg2
In commit 0d72b92883c651a11059d93335f33d65c6eb653b, a new u32 argument
for the request_mask was added to generic_fillattr. This is the same
request_mask for statx that's present in the most recent API implemented
by zpl_getattr_impl. This commit conditionally adds it to the
zpl_generic_fillattr(...) macro, as well as the zfs_getattr_fast(...)
implementation, when configure determines it's present in the kernel's
generic_fillattr(...).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15263
2023-09-21 18:38:40 -07:00
Coleman Kane
b37f29341b Linux 6.6 compat: use inode_get/set_ctime*(...)
In Linux commit 13bc24457850583a2e7203ded05b7209ab4bc5ef, direct access
to the i_ctime member of struct inode was removed. The new approach is
to use accessor methods that exclusively handle passing the timestamp
around by value. This change adds new tests for each of these functions
and introduces zpl_* equivalents in include/os/linux/zfs/sys/zpl.h. In
where the inode_get/set_ctime*() functions exist, these zpl_* calls will
be mapped to the new functions. On older kernels, these macros just wrap
direct-access calls. The code that operated on an address of ip->i_ctime
to call ZFS_TIME_DECODE() now will take a local copy using
zpl_inode_get_ctime(), and then pass the address of the local copy when
performing the ZFS_TIME_DECODE() call, in all cases, rather than
directly accessing the member.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15263
Closes #15257
2023-09-21 18:38:31 -07:00
Mateusz Guzik
ee720ad7bc
Retire z_nr_znodes
Added in ab26409db7 ("Linux 3.1 compat, super_block->s_shrink"), with
the only consumer which needed the count getting retired in 066e825221
("Linux compat: Minimum kernel version 3.10").

The counter gets in the way of not maintaining the list to begin with.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes #15274
2023-09-18 16:53:33 -07:00
Volker Mauel
12ce45f260
Intel QAT 1.7 compatibility
Based on the intel QAT samples which are bundled in the 1.x drivers, 
this is the preferred approach since api version 1.6.  See:

https://www.intel.de/content/www/de/de/download/19734/intel-quickassist-technology-driver-for-linux-hw-version-1-x.html?

Reviewed-by: Weigang Li <weigang.li@intel.com>
Signed-off-by: Volker Mauel <volkermauel@gmail.com>
Closes #15190
2023-09-07 14:38:17 -07:00
Andrea Righi
3602775330
Linux 6.5 compat: spl: properly unregister sysctl entries
When register_sysctl_table() is unavailable we fail to properly
unregister sysctl entries under "kernel/spl".

This leads to errors like the following when spl is unloaded/reloaded,
making impossible to properly reload the spl module:

[  746.995704] sysctl duplicate entry: /kernel/spl/kmem/slab_kvmem_total

Fix by cleaning up all the sub-entries inside "kernel/spl" when the
spl module is unloaded.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Closes #15239
2023-09-07 14:36:32 -07:00
ednadolski-ix
95f71c019d
Selectable block allocators
ZFS historically has had several space allocators that were
dynamically selectable.  While these have been retained in 
OpenZFS, only a single allocator has been statically compiled 
in. This patch compiles all allocators for OpenZFS and provides 
a module parameter to allow for manual selection between them.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Edmund Nadolski <edmund.nadolski@ixsystems.com>
Closes #15218
2023-09-01 18:00:30 -07:00
Andrea Righi
bcb1159c09
Linux 6.5 compat: safe cleanup in spl_proc_fini()
If we fail to create a proc entry in spl_proc_init() we may end up
calling unregister_sysctl_table() twice: one in the failure path of
spl_proc_init() and another time during spl_proc_fini().

Avoid the double call to unregister_sysctl_table() and while at it
refactor the code a bit to reduce code duplication.

This was accidentally introduced when the spl code was
updated for Linux 6.5 compatibility.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Closes #15234 
Closes #15235
2023-09-01 17:21:40 -07:00
Rob N
cae502c175
copy_file_range: fix fallback when source create on same txg
In 019dea0a5 we removed the conversion from EAGAIN->EXDEV inside
zfs_clone_range(), but forgot to add a test for EAGAIN to the
copy_file_range() entry points to trigger fallback to a content copy.

This commit fixes that.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #15170
Closes #15172
2023-08-14 17:34:14 -07:00
Coleman Kane
8ce2eba9e6
Linux 6.5 compat: Use copy_splice_read instead of filemap_splice_read
Using the filemap_splice_read function for the splice_read handler was
leading to occasional data corruption under certain circumstances. Favor
using copy_splice_read instead, which does not demonstrate the same
erroneous behavior under the tested failure cases.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15164
2023-08-08 15:42:32 -07:00
oromenahar
019dea0a55
zfs_clone_range should return a descriptive error codes
Return the more descriptive error codes instead of `EXDEV` when
the parameters don't match the requirements of the clone function.
Updated the comments in `brt.c` accordingly.
The first three errors are just invalid parameters, which zfs can
not handle.
The fourth error indicates that the block which should be cloned
is created and cloned or modified in the same transaction
group (`txg`).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rob Norris <rob.norris@klarasystems.com>
Signed-off-by: Kay Pedersen <mail@mkwg.de>
Closes #15148
2023-08-08 09:37:06 -07:00
Coleman Kane
36261c8238
Linux 6.5 compat: replace generic_file_splice_read with filemap_splice_read
The generic_file_splice_read function was removed in Linux 6.5 in favor
of filemap_splice_read. Add an autoconf test for filemap_splice_read and
use it if it is found as the handler for .splice_read in the
file_operations struct. Additionally, ITER_PIPE was removed in 6.5. This
change removes the ITER_* macros that OpenZFS doesn't use from being
tested in config/kernel-vfs-iov_iter.m4. The removal of ITER_PIPE was
causing the test to fail, which also affected the code responsible for
setting the .splice_read handler, above. That behavior caused run-time
panics on Linux 6.5.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15155
2023-08-07 15:47:46 -07:00
Alexander Motin
6c94e64963
Refactor dmu_prefetch().
- Split dmu_prefetch_dnode() from dmu_prefetch() into a separate
function.  It is quite inconvenient to read the code where len = 0
means dnode prefetch instead indirect/data prefetch.  One function
doing both has no benefits, since the code paths are independent.
 - Improve dmu_prefetch() handling of long block ranges.  Instead
of limiting L0 data length to prefetch for to dmu_prefetch_max,
make dmu_prefetch_max limit the actual amount of prefetch at the
specified level, and, if there is more, prefetch all the rest at
higher indirection level.  It should improve random access times
within the prefetched range of any length, reducing importance of
specific dmu_prefetch_max value.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15076
2023-08-07 13:54:41 -07:00
Coleman Kane
e47e9bbe86
Linux 6.5 compat: register_sysctl_table removed
Additionally, the .child element of ctl_table has been removed in 6.5.
This change adds a new test for the pre-6.5 register_sysctl_table()
function, and uses the old code in that case. If it isn't found, then
the parentage entries in the tables are removed, and the register_sysctl
call is provided the paths of "kernel/spl", "kernel/spl/kmem", and
"kernel/spl/kstat" directly, to populate each subdirectory over three
calls, as is the new API.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15138
2023-08-02 14:05:46 -07:00
Brian Atkinson
a5fdba1185
Revert "Linux 6.5 compat: register_sysctl_table removed"
This reverts commit b35374fd64 as there
are error messages when loading the SPL module. Errors seemed to be tied
to duplicate a duplicate entry.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes #15134
2023-08-01 14:48:19 -07:00
Rob N
ead3eea3e0
linux/copy_file_range: properly request a fallback copy on Linux <5.3
Before Linux 5.3, the filesystem's copy_file_range handler had to signal
back to the kernel that we can't fulfill the request and it should
fallback to a content copy. This is done by returning -EOPNOTSUPP.

This commit converts the EXDEV return from zfs_clone_range to
EOPNOTSUPP, to force the kernel to fallback for all the valid reasons it
might be unable to clone. Without it the copy_file_range() syscall will
return EXDEV to userspace, breaking its semantics.

Add test for copy_file_range fallbacks.  copy_file_range should always
fallback to a content copy whenever ZFS can't service the request with
cloning.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #15131
2023-08-01 11:31:11 -07:00
наб
a21ca18d4d
linux: zfs: ctldir: set [amc]time to snapshot's creation property
If looking up a snapdir inode failed, hold pool config – hold the 
snapshot – get its creation property – release it – release it, 
then use that as the [amc]time in the allocated inode. If that 
fails then fall back to current time. No performance impact since 
this is only done when allocating a new snapdir inode.
                                                       
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #15110
Closes #15117
2023-08-01 08:50:17 -07:00
Coleman Kane
6751634d77 Linux 4.20 compat: wrapper function for iov_iter type access
An iov_iter_type() function to access the "type" member of the struct
iov_iter was added at one point. Move the conditional logic to decide
which method to use for accessing it into a macro and simplify the
zpl_uio_init code.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15100
2023-08-01 08:42:33 -07:00
Coleman Kane
325505e5c4 Linux 6.4 compat: iter_iov() function now used to get old iov member
The iov_iter->iov member is now iov_iter->__iov and must be accessed via
the accessor function iter_iov(). Create a wrapper that is conditionally
compiled to use the access method appropriate for the target kernel
version.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15100
2023-08-01 08:42:26 -07:00
Coleman Kane
43e8f6e37f
Linux 6.5 compat: blkdev changes
Multiple changes to the blkdev API were introduced in Linux 6.5. This
includes passing (void* holder) to blkdev_put, adding a new
blk_holder_ops* arg to blkdev_get_by_path, adding a new blk_mode_t type
that replaces uses of fmode_t, and removing an argument from the release
handler on block_device_operations that we weren't using. The open
function definition has also changed to take gendisk* and blk_mode_t, so
update it accordingly, too.

Implement local wrappers for blkdev_get_by_path() and
vdev_blkdev_put() so that the in-line calls are cleaner, and place the
conditionally-compiled implementation details inside of both of these
local wrappers. Both calls are exclusively used within vdev_disk.c, at
this time.

Add blk_mode_is_open_write() to test FMODE_WRITE / BLK_OPEN_WRITE
The wrapper function is now used for testing using the appropriate
method for the kernel, whether the open mode is writable or not.

Emphasize fmode_t arg in zvol_release is not used

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15099
2023-08-01 08:37:20 -07:00
Coleman Kane
b35374fd64
Linux 6.5 compat: register_sysctl_table removed
Additionally, the .child element of ctl_table has been removed in 6.5.
This change adds a new test for the pre-6.5 register_sysctl_table()
function, and uses the old code in that case. If it isn't found, then
the parentage entries in the tables are removed, and the register_sysctl
call is provided the paths of "kernel/spl", "kernel/spl/kmem", and
"kernel/spl/kstat" directly, to populate each subdirectory over three
calls, as is the new API.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #15098
2023-08-01 08:27:58 -07:00
Rob Norris
6b0a4be5fe linux: implement filesystem-side copy/clone functions for EL7
Redhat have backported copy_file_range and clone_file_range to the EL7
kernel using an "extended file operations" wrapper structure. This
connects all that up to let cloning work there too.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes #15050
2023-07-24 16:37:04 -07:00
Rob Norris
9927f219f1 linux: implement filesystem-side clone ioctls
Prior to Linux 4.5, the FICLONE etc ioctls were specific to BTRFS, and
were implemented as regular filesystem-specific ioctls. This implements
those ioctls directly in OpenZFS, allowing cloning to work on older
kernels.

There's no need to gate these behind version checks; on later kernels
Linux will simply never deliver these ioctls, instead calling the
approprate VFS op.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes #15050
2023-07-24 16:36:54 -07:00
Rob Norris
5a35c68b67 linux: implement filesystem-side copy/clone functions
This implements the Linux VFS ops required to service the file
copy/clone APIs:

  .copy_file_range    (4.5+)
  .clone_file_range   (4.5-4.19)
  .dedupe_file_range  (4.5-4.19)
  .remap_file_range   (4.20+)

Note that dedupe_file_range() and remap_file_range(REMAP_FILE_DEDUP) are
hooked up here, but are not implemented yet.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Closes #15050
2023-07-24 16:36:38 -07:00
Chunwei Chen
2d8a2b51dc
Fix zpl_test_super race with zfs_umount
We cannot call zpl_enter in zpl_test_super, because zpl_test_super is
under spinlock so we can't sleep, and also because zpl_test_super is
called without sb->s_umount taken, so it's possible we would race with
zfs_umount and call zpl_enter on freed zfsvfs.

Here's an stack trace when this happens:
[ 2379.114837] VERIFY(cvp->cv_magic == CV_MAGIC) failed
[ 2379.114845] PANIC at spl-condvar.c:497:__cv_broadcast()
[ 2379.114854] Kernel panic - not syncing: VERIFY(cvp->cv_magic == CV_MAGIC) failed
[ 2379.115012] Call Trace:
[ 2379.115019]  dump_stack+0x74/0x96
[ 2379.115024]  panic+0x114/0x2f6
[ 2379.115035]  spl_panic+0xcf/0xfc [spl]
[ 2379.115477]  __cv_broadcast+0x68/0xa0 [spl]
[ 2379.115585]  rrw_exit+0xb8/0x310 [zfs]
[ 2379.115696]  rrm_exit+0x4a/0x80 [zfs]
[ 2379.115808]  zpl_test_super+0xa9/0xd0 [zfs]
[ 2379.115920]  sget+0xd1/0x230
[ 2379.116033]  zpl_mount+0xdc/0x230 [zfs]
[ 2379.116037]  legacy_get_tree+0x28/0x50
[ 2379.116039]  vfs_get_tree+0x27/0xc0
[ 2379.116045]  path_mount+0x2fe/0xa70
[ 2379.116048]  do_mount+0x80/0xa0
[ 2379.116050]  __x64_sys_mount+0x8b/0xe0
[ 2379.116052]  do_syscall_64+0x35/0x50
[ 2379.116054]  entry_SYSCALL_64_after_hwframe+0x61/0xc6
[ 2379.116057] RIP: 0033:0x7f9912e8b26a

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes #15077
2023-07-20 10:30:21 -07:00
Prakash Surya
945e39fc3a
Enable tuning of ZVOL open timeout value
The default timeout for ZVOL opens may not be sufficient for all cases,
so we should enable the value to be more easily tuned to account for
systems where the default value is insufficient.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Prakash Surya <prakash.surya@delphix.com>
Closes #15023
2023-06-30 11:34:05 -07:00
Rich Ercolani
35a6247c5f
Add a delay to tearing down threads.
It's been observed that in certain workloads (zvol-related being a
big one), ZFS will end up spending a large amount of time spinning
up taskqs only to tear them down again almost immediately, then
spin them up again...

I noticed this when I looked at what my mostly-idle system was doing
and wondered how on earth taskq creation/destroy was a bunch of time...

So I added a configurable delay to avoid it tearing down tasks the
first time it notices them idle, and the total number of threads at
steady state went up, but the amount of time being burned just
tearing down/turning up new ones almost vanished.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes #14938
2023-06-26 13:57:12 -07:00
Alexander Motin
b3ad3f48d9
Use list_remove_head() where possible.
... instead of list_head() + list_remove().  On FreeBSD the list
functions are not inlined, so in addition to more compact code
this also saves another function call.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14955
2023-06-09 10:12:52 -07:00
Brian Behlendorf
93f8abeff0
Linux: Never sleep in kmem_cache_alloc(..., KM_NOSLEEP) (#14926)
When a kmem cache is exhausted and needs to be expanded a new
slab is allocated.  KM_SLEEP callers can block and wait for the
allocation, but KM_NOSLEEP callers were incorrectly allowed to
block as well.

Resolve this by attempting an emergency allocation as a best
effort.  This may fail but that's fine since any KM_NOSLEEP
consumer is required to handle an allocation failure.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Adam Moss <c@yotes.com>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
2023-06-07 10:43:43 -07:00
Rob Norris
2b9f8ba673 znode: expose zfs_get_zplprop to libzpool
There's no particular reason this function should be kernel-only, and I
want to use it (indirectly) from zdb. I've moved it to zfs_znode.c
because libzpool does not compile in zfs_vfsops.c, and this at least
matches the header its imported from.

Sponsored-By: Klara, Inc.
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: WHR <msl0000023508@gmail.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #14642
2023-06-05 11:53:44 -07:00
youzhongyang
f8447cf22e
Linux 6.4 compat: reclaimed_slab renamed to reclaimed
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes #14891
2023-05-24 12:23:42 -07:00
Richard Yao
ab71b24d20 Linux: zfs_zaccess_trivial() should always call generic_permission()
Building with Clang on Linux generates a warning that err could be
uninitialized if mnt_ns is a NULL pointer. However, mnt_ns should never
be NULL, so there is no need to put this behind an if statement.  Taking
it outside of the if statement means that the possibility of err being
uninitialized goes from being always zero in a way that the compiler
could not realize to a way that is always zero in a way that the
compiler can realize.

Sponsored-By: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Youzhong Yang <yyang@mathworks.com>
Signed-off-by: Richard Yao <richard.yao@klarasystems.com>
Closes #14738
2023-04-20 10:29:44 -07:00
youzhongyang
d4dc53dad2
Linux 6.3 compat: idmapped mount API changes
Linux kernel 6.3 changed a bunch of APIs to use the dedicated idmap 
type for mounts (struct mnt_idmap), we need to detect these changes 
and make zfs work with the new APIs.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes #14682
2023-04-10 14:15:36 -07:00
youzhongyang
8eb2f26057
Linux 6.3 compat: writepage_t first arg struct folio*
The type def of writepage_t in kernel 6.3 is changed to take
struct folio* as the first argument. We need to detect this
change and pass correct function to write_cache_pages().

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes #14699
2023-04-05 10:01:38 -07:00
Brian Behlendorf
1142362ff6
Use vmem_zalloc to silence allocation warning
The kmem allocation in zfs_prune_aliases() will trigger a large
allocation warning on systems with 64K pages.  Resolve this by
switching to vmem_alloc() which internally uses kvmalloc() so the
right allocator will be used based on the allocation size.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8491
Closes #14694
2023-03-31 09:43:54 -07:00
naivekun
60cfd3bbc2
QAT: Fix uninitialized seed in QAT compression
CpaDcRqResults have to be initialized with checksum=1 for adler32.
Otherwise when error CPA_DC_OVERFLOW occurred, the next compress
operation will continue on previously part-compressed data, and write
invalid checksum data. When zfs decompress the compressed data, a
invalid checksum will occurred and lead to #14463

Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Weigang Li <weigang.li@intel.com>
Reviewed-by: Chengfei Zhu <chengfeix.zhu@intel.com>
Signed-off-by: naivekun <naivekun0817@gmail.com>
Closes #14632
Closes #14463
2023-03-16 11:54:10 -07:00
Richard Yao
d1807f168e nvpair: Constify string functions
After addressing coverity complaints involving `nvpair_name()`, the
compiler started complaining about dropping const. This lead to a rabbit
hole where not only `nvpair_name()` needed to be constified, but also
`nvpair_value_string()`, `fnvpair_value_string()` and a few other static
functions, plus variable pointers throughout the code. The result became
a fairly big change, so it has been split out into its own patch.

Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14612
2023-03-14 15:25:50 -07:00
Richard Yao
703283fabd Linux: Fix octal detection in define_ddi_strtox()
Clang Tidy reported this as a misc-redundant-expression because writing
`8` instead of `'8'` meant that the condition could never be true.

The only place where we have a chance of this being a bug would be in
nvlist_lookup_nvpair_ei_sep(). I am not sure if we ever pass an octal to
that, but if we ever do, it should work properly now instead of failing.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14575
2023-03-08 13:52:09 -08:00
Richard Yao
66a38fd10a Linux: Suppress clang static analyzer warning in zfs_remove()
Clang's static analyzer points out that if we fail to find an extended
attribute directory, but somehow find it when calculating delete_now and
delete_now is true, we will have a NULL pointer dereference when we try
to unlink the extended attribute directory.

I am not sure if this is possible, but if it is, I do not see a sane way
of handling this other than rolling back the transaction and retrying.
For now, let us do an VERIFY_IMPLY(). If this trips, it will stop the
transaction from committing, which will prevent an attribute directory
leak.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14575
2023-03-08 13:52:04 -08:00
Richard Yao
c2550a136e Linux: Silence static analyzer warning in crypto_create_ctx_template()
A CodeChecker report from Clang's CTU analysis indicated that we were
assigning uninitialized values in crypto_create_ctx_template() when we
call it from zio_crypt_key_init(). This occurs because the ->cm_param
and ->cm_param_len fields are uninitialized. Thankfully, the
uninitialized values are only used in the skein via
KCF_PROV_CREATE_CTX_TEMPLATE() -> skein_create_ctx_template() ->
skein_mac_ctx_build() -> skein_get_digest_bitlen(), but that should not
be called from here. We fix this to avoid a possible trap should this
code change in the future.

The FreeBSD version of zio_crypt_key_init() is unaffected.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14575
2023-03-08 13:51:59 -08:00
Richard Yao
5dd0f019cd Linux cleanup: zvol_discard() should only call blk_queue_io_stat() once
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14575
2023-03-08 13:51:40 -08:00
Alexander Motin
a8d83e2a24
More adaptive ARC eviction
Traditionally ARC adaptation was limited to MRU/MFU distribution.  But
for years people with metadata-centric workload demanded mechanisms to
also manage data/metadata distribution, that in original ZFS was just
a FIFO.  As result ZFS effectively got separate states for data and
metadata, minimum and maximum metadata limits etc, but it all required
manual tuning, was not adaptive and in its heart remained a bad FIFO.

This change removes most of existing eviction logic, rewriting it from
scratch.  This makes MRU/MFU adaptation individual for data and meta-
data, same as the distribution between data and metadata themselves.
Since most of required states separation was already done, it only
required to make arcs_size state field specific per data/metadata.

The adaptation logic is still based on previous concept of ghost hits,
just now it balances ARC capacity between 4 states: MRU data, MRU
metadata, MFU data and MFU metadata.  To simplify arc_c changes instead
of arc_p measured in bytes, this code uses 3 variable arc_meta, arc_pd
and arc_pm, representing ARC balance between metadata and data, MRU and
MFU for data, and MRU and MFU for metadata respectively as 32-bit fixed
point fractions.  Since we care about the math result only when need to
evict, this moves all the logic from arc_adapt() to arc_evict(), that
reduces per-block overhead, since per-block operations are limited to
stats collection, now moved from arc_adapt() to arc_access() and using
cheaper wmsums.  This also allows to remove ugly ARC_HDR_DO_ADAPT flag
from many places.

This change also removes number of metadata specific tunables, part of
which were actually not functioning correctly, since not all metadata
are equal and some (like L2ARC headers) are not really evictable.
Instead it introduced single opaque knob zfs_arc_meta_balance, tuning
ARC's reaction on ghost hits, allowing administrator give more or less
preference to metadata without setting strict limits.

Some of old code parts like arc_evict_meta() are just removed, because
since introduction of ABD ARC they really make no sense: only headers
referenced by small number of buffers are not evictable, and they are
really not evictable no matter what this code do.  Instead just call
arc_prune_async() if too much metadata appear not evictable.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes #14359
2023-03-08 11:17:23 -08:00
Richard Yao
dd108f5d73
Linux: zfs_fillpage() should handle partial pages from end of file
After 89cd2197b9 was merged, Clang's
static analyzer began complaining about a dead assignment in
`zfs_fillpage()`. Upon inspection, I noticed that the dead assignment
was because we are not using the calculated io_len that we should use to
avoid asking the DMU to read past the end of a file. This should result
in `dmu_buf_hold_array_by_dnode()` calling `zfs_panic_recover()`.

This issue predates 89cd2197b9, but its
simplification of zfs_fillpage() eliminated the only use of the
assignment to io_len, which made Clang's static analyzer complain about
the issue.

Also, as a precaution, we add an assertion that io_offset < i_size. If
this ever fails, bad things will happen. Otherwise, we are blindly
trusting the kernel not to give us invalid offsets. We continue to
blindly trust it on non-debug kernels.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14534
2023-03-01 13:19:47 -08:00
John Poduska
73c383f541
Prevent incorrect datasets being mounted
During a mount, zpl_mount_impl(), uses sget() with the callback
zpl_test_super() to find a super_block with a matching objset,
stored in z_os. It does so without taking the teardown lock on
the zfsvfs.

The problem is that operations like rollback will replace the
z_os. And, there is a window where the objset in the rollback
is freed, but z_os still points to it. Then, a mount like
operation, for instance a clone, can reallocate that exact same
pointer and zpl_test_super() will then match the super_block
associated with the rollback as opposed to the clone.

This fix tests for a match and if so, takes the teardown lock
before doing the final match test.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: John Poduska <jpoduska@datto.com>
Closes #14518
2023-02-27 16:49:34 -08:00
Brian Behlendorf
89cd2197b9
Fix buffered/direct/mmap I/O race
When a page is faulted in for memory mapped I/O the page lock
may be dropped before it has been read and marked up to date.
If a buffered read encounters such a page in mappedread() it
must wait until the page has been updated. Failure to do so
will result in a panic on debug builds and incorrect data on
production builds.

The critical part of this change is in mappedread() where pages
which are not up to date are now handled. Additionally, it
includes the following simplifications.

- zfs_getpage() and zfs_fillpage() could be passed an array of
  pages. This could be more efficient if it was used but in
  practice only a single page was ever provided. These
  interfaces were simplified to acknowledge that.

- update_pages() was modified to correctly set the PG_error bit
  on a page when it cannot be read by dmu_read().

- Setting PG_error and PG_uptodate was moved to zfs_fillpage()
  from zpl_readpage_common(). This is consistent with the
  handling in update_pages() and mappedread().

- Minor additional refactoring to comments and variable
  declarations to improve readability.

- Add a test case to exercise concurrent buffered, direct,
  and mmap IO to the same file.

- Reduce the mmap_sync test case default run time.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #13608 
Closes #14498
2023-02-23 10:57:24 -08:00
Brian Behlendorf
3fc92adc40
Linux: use filemap_range_has_page()
As of the 4.13 kernel filemap_range_has_page() can be used to
check if there is a page mapped in a given file range.  When
available this interface should be used which eliminates the
need for the zp->z_is_mapped boolean.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #14493
2023-02-14 11:04:34 -08:00
Rich Ercolani
cfd57573ff
quick fix for lingering snapdir unmount problems
Unfortunately, even after e79b6807, I still, much more rarely,
tripped asserts when playing with many ctldir mounts at once.

Since this appears to happen if we dispatched twice too fast, just
ignore it. We don't actually need to do anything if someone already
started doing it for us.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes #14462
2023-02-13 16:40:13 -08:00
Prakash Surya
13312e2fa1
Reduce need for contiguous memory for ioctls
We've had cases where we trigger an OOM despite having memory freely
available on the system. For example, here, we had about 21GB free:

    kernel: Node 0 Normal: 2418758*4kB (UME) 1549533*8kB (UE) 0*16kB
    0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB =
    22071296kB

The problem being, all the memory is in 4K and 8K contiguous regions,
but the allocation request was for a 16K contiguous region:

    kernel: SafeExecutors-4 invoked oom-killer:
    gfp_mask=0x42dc0(GFP_KERNEL|__GFP_NOWARN|__GFP_COMP|__GFP_ZERO),
    order=2, oom_score_adj=0

The offending allocation came from this call trace:

    kernel: Call Trace:
    kernel:  dump_stack+0x57/0x7a
    kernel:  dump_header+0x4f/0x1e1
    kernel:  oom_kill_process.cold.33+0xb/0x10
    kernel:  out_of_memory+0x1ad/0x490
    kernel:  __alloc_pages_slowpath+0xd55/0xe40
    kernel:  __alloc_pages_nodemask+0x2df/0x330
    kernel:  kmalloc_large_node+0x42/0x90
    kernel:  __kmalloc_node+0x25a/0x320
    kernel:  ? spl_kmem_free_impl+0x21/0x30 [spl]
    kernel:  spl_kmem_alloc_impl+0xa5/0x100 [spl]
    kernel:  spl_kmem_zalloc+0x19/0x20 [spl]
    kernel:  zfsdev_ioctl+0x2b/0xe0 [zfs]
    kernel:  do_vfs_ioctl+0xa9/0x640
    kernel:  ? __audit_syscall_entry+0xdd/0x130
    kernel:  ksys_ioctl+0x67/0x90
    kernel:  __x64_sys_ioctl+0x1a/0x20
    kernel:  do_syscall_64+0x5e/0x200
    kernel:  entry_SYSCALL_64_after_hwframe+0x44/0xa9
    kernel: RIP: 0033:0x7fdca3674317

The problem is, for each ioctl that ZFS makes, it has to allocate a
zfs_cmd_t structure, which is 13744 bytes in size (on my system):

    sdb> sizeof zfs_cmd
    (size_t)13744

This size, coupled with the fact that we currently allocate it with
kmem_zalloc, means we need a 16K contiguous region of memory to satisfy
the request.

The solution taken by this change, is to use "vmem" instead of "kmem" to
do the allocation, such that we don't necessarily need a contiguous 16K
memory region to satisfy the allocation.

Arguably, a better solution would be not to require such a large
allocation to begin with (e.g. reduce the size of the zfs_cmd_t
structure), but that'd be a much larger change than this "one liner".
Thus, I've opted for this approach for now; we can always circle back
and attempt to reduce the size of the structure in the future.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: Don Brady <don.brady@delphix.com>
Signed-off-by: Prakash Surya <prakash.surya@delphix.com>
Closes #14474
2023-02-13 16:35:59 -08:00
Richard Yao
66953686c0 Add assertion and make variables unsigned in abd_alloc_chunks()
Clang's static analyzer pointed out that if alloc_pages >= nr_pages
before the loop, the value of page will be undefined and will be used
anyway. This should not be possible, but as cleanup, we add an
assertion. We also recognize that the local variables should be unsigned
in the first place, so we make them unsigned. This is not enough to
avoid the need for the assertion, since there is still the case that
alloc_pages == nr_pages and nr_pages == 0, which the assertion
implicitly checks.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14456
2023-02-06 11:10:50 -08:00
Richard Yao
3a7d2a0ce0 zfs_get_temporary_prop() should not pass NULL to strcpy()
`dsl_dir_activity_in_progress()` can call `zfs_get_temporary_prop()` with
the forth value set to NULL, which will pass NULL to `strcpy()` when
there is a match

Clang's static analyzer caught this with the help of CodeChecker for
Cross Translation Unit analysis.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14456
2023-02-06 11:08:57 -08:00
Coleman Kane
9cd71c8604
linux 6.2 compat: zpl_set_acl arg2 is now struct dentry
Linux 6.2 changes the second argument of the set_acl operation to be a
"struct dentry *" rather than a "struct inode *". The inode* parameter
is still available as dentry->d_inode, so adjust the call to the _impl
function call to dereference and pass that pointer to it.

Also document that the get_acl -> get_inode_acl member name change from
commit 884a693 was an API change also introduced in Linux 6.2.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #14415
2023-01-24 11:20:50 -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
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
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
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
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
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
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
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
Alexander
b5459dd354
Fix the last two CFI callback prototype mismatches
There was the series from me a year ago which fixed most of the
callback vs implementation prototype mismatches. It was based on
running the CFI-enabled kernel (in permissive mode -- warning
instead of panic) and performing a full ZTS cycle, and then fixing
all of the problems caught by CFI.
Now, Clang 16-dev has new warning flag, -Wcast-function-type-strict,
which detect such mismatches at compile-time. It allows to find the
remaining issues missed by the first series.
There are only two of them left: one for the
secpolicy_vnode_setattr() callback and one for taskq_dispatch().
The fix is easy, since they are not used anywhere else.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Closes #14207
2022-11-29 09:56:16 -08:00
Alexander Motin
5f45e3f699
Remove atomics from zh_refcount
It is protected by z_hold_locks, so we do not need more serialization,
simple integer math should be fine.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by:  Alexander Motin <mav@FreeBSD.org>
Closes #14196
2022-11-28 11:36:53 -08:00
Richard Yao
b1eec00904 Cleanup: Suppress Coverity dereference before/after NULL check reports
f224eddf92 began dereferencing a NULL
checked pointer in zpl_vap_init(), which made Coverity complain because
either the dereference is unsafe or the NULL check is unnecessary. Upon
inspection, this pointer is guaranteed to never be NULL because it is
from the Linux kernel VFS. The calls into ZFS simply would not make
sense if this pointer were NULL, so the NULL check is unnecessary.

Reported-by: Coverity (CID 1527260)
Reported-by: Coverity (CID 1527262)
Reviewed-by: Mariusz Zaborski <mariusz.zaborski@klarasystems.com>
Reviewed-by: Youzhong Yang <yyang@mathworks.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14170
2022-11-10 13:58:05 -08:00
Mariusz Zaborski
16f0fdaddd
Allow to control failfast
Linux defaults to setting "failfast" on BIOs, so that the OS will not
retry IOs that fail, and instead report the error to ZFS.

In some cases, such as errors reported by the HBA driver, not
the device itself, we would wish to retry rather than generating
vdev errors in ZFS. This new property allows that.

This introduces a per vdev option to disable the failfast option.
This also introduces a global module parameter to define the failfast
mask value.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Mariusz Zaborski <mariusz.zaborski@klarasystems.com>
Sponsored-by: Seagate Technology LLC
Submitted-by: Klara, Inc.
Closes #14056
2022-11-10 13:37:12 -08:00
Alan Somers
e197bb24f1
Optionally skip zil_close during zvol_create_minor_impl
If there were no zil entries to replay, skip zil_close.  zil_close waits
for a transaction to sync.  That can take several seconds, for example
during pool import of a resilvering pool.  Skipping zil_close can cut
the time for "zpool import" from 2 hours to 45 seconds on a resilvering
pool with a thousand zvols.

Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Sponsored-by: Axcient
Closes #13999 
Closes #14015
2022-11-08 12:38:08 -08:00
youzhongyang
f224eddf92
Support idmapped mount in user namespace
Linux 5.17 commit torvalds/linux@5dfbfe71e enables "the idmapping 
infrastructure to support idmapped mounts of filesystems mounted 
with an idmapping". Update the OpenZFS accordingly to improve the 
idmapped mount support. 

This pull request contains the following changes:

- xattr setter functions are fixed to take mnt_ns argument. Without
  this, cp -p would fail for an idmapped mount in a user namespace.
- idmap_util is enhanced/fixed for its use in a user ns context.
- One test case added to test idmapped mount in a user ns.

Reviewed-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes #14097
2022-11-08 10:28:56 -08:00
Serapheim Dimitropoulos
f66ffe6878
Expose zfs_vdev_open_timeout_ms as a tunable
Some of our customers have been occasionally hitting zfs import failures
in Linux because udevd doesn't create the by-id symbolic links in time
for zpool import to use them. The main issue is that the
systemd-udev-settle.service that zfs-import-cache.service and other
services depend on is racy. There is also an openzfs issue filed (see
https://github.com/openzfs/zfs/issues/10891) outlining the problem and
potential solutions.

With the proper solutions being significant in terms of complexity and
the priority of the issue being low for the time being, this patch
exposes `zfs_vdev_open_timeout_ms` as a tunable so people that are
experiencing this issue often can increase it as a workaround.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Don Brady <don.brady@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #14133
2022-11-03 15:02:46 -07:00
Richard Yao
11e3416ae7
Cleanup: Remove branches that always evaluate the same way
Coverity reported that the ASSERT in taskq_create() is always true and
the `*offp > MAXOFFSET_T` check in zfs_file_seek() is always false.

We delete them as cleanup.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14130
2022-11-03 10:47:48 -07:00
Brooks Davis
d96303cb07 acl: use uintptr_t for ace walker cookies
Avoid assuming that a pointer can fit in a uint64_t and use uintptr_t
instead.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Brooks Davis <brooks.davis@sri.com>
Closes #14131
2022-11-03 09:51:34 -07:00
Richard Yao
97143b9d31 Introduce kmem_scnprintf()
`snprintf()` is meant to protect against buffer overflows, but operating
on the buffer using its return value, possibly by calling it again, can
cause a buffer overflow, because it will return how many characters it
would have written if it had enough space even when it did not. In a
number of places, we repeatedly call snprintf() by successively
incrementing a buffer offset and decrementing a buffer length, by its
return value. This is a potentially unsafe usage of `snprintf()`
whenever the buffer length is reached. CodeQL complained about this.

To fix this, we introduce `kmem_scnprintf()`, which will return 0 when
the buffer is zero or the number of written characters, minus 1 to
exclude the NULL character, when the buffer was too small. In all other
cases, it behaves like snprintf(). The name is inspired by the Linux and
XNU kernels' `scnprintf()`. The implementation was written before I
thought to look at `scnprintf()` and had a good name for it, but it
turned out to have identical semantics to the Linux kernel version.
That lead to the name, `kmem_scnprintf()`.

CodeQL only catches this issue in loops, so repeated use of snprintf()
outside of a loop was not caught. As a result, a thorough audit of the
codebase was done to examine all instances of `snprintf()` usage for
potential problems and a few were caught. Fixes for them are included in
this patch.

Unfortunately, ZED is one of the places where `snprintf()` is
potentially used incorrectly. Since using `kmem_scnprintf()` in it would
require changing how it is linked, we modify its usage to make it safe,
no matter what buffer length is used. In addition, there was a bug in
the use of the return value where the NULL format character was not
being written by pwrite(). That has been fixed.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14098
2022-10-29 13:05:11 -07:00