Commit Graph

151 Commits

Author SHA1 Message Date
Paul B. Henson
7bf3e1fa0f OpenZFS 3254 - add support in zfs for aclmode=restricted
Authored-by: Paul B. Henson <henson@acm.org>
Reviewed by: Albert Lee <trisk@nexenta.com>
Reviewed by: Gordon Ross <gwr@nexenta.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Richard Lowe <richlowe@richlowe.net>
Ported-by: Paul B. Henson <henson@acm.org>

OpenZFS-issue: https://www.illumos.org/issues/3254
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/71dbfc287c
Closes #10266
2020-04-30 11:23:59 -07:00
Paul B. Henson
a1af567bb6 OpenZFS 742 - Resurrect the ZFS "aclmode" property OpenZFS 664 - Umask masking "deny" ACL entries OpenZFS 279 - Bug in the new ACL (post-PSARC/2010/029) semantics
Porting notes:
* Updated zfs_acl_chmod to take 'boolean_t isdir' as first parameter
  rather than 'zfsvfs_t *zfsvfs'
* zfs man pages changes mixed between zfs and new zfsprops man pages

Reviewed by: Aram Hvrneanu <aram@nexenta.com>
Reviewed by: Gordon Ross <gwr@nexenta.com>
Reviewed by: Robert Gordon <rbg@openrbg.com>
Reviewed by: Mark.Maybee@oracle.com
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Garrett D'Amore <garrett@nexenta.com>
Ported-by: Paul B. Henson <henson@acm.org>

OpenZFS-issue: https://www.illumos.org/issues/742
OpenZFS-issue: https://www.illumos.org/issues/664
OpenZFS-issue: https://www.illumos.org/issues/279
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/a3c49ce110
Closes #10266
2020-04-30 11:22:45 -07:00
Fabio Scaccabarozzi
c9e3efdb3a
Bugfix/fix uio partial copies
In zfs_write(), the loop continues to the next iteration without
accounting for partial copies occurring in uiomove_iov when 
copy_from_user/__copy_from_user_inatomic return a non-zero status.
This results in "zfs: accessing past end of object..." in the 
kernel log, and the write failing.

Account for partial copies and update uio struct before returning
EFAULT, leave a comment explaining the reason why this is done.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: ilbsmart <wgqimut@gmail.com>
Signed-off-by: Fabio Scaccabarozzi <fsvm88@gmail.com>
Closes #8673 
Closes #10148
2020-04-01 09:48:54 -07:00
Matthew Ahrens
3f38797338
Compile cityhash code into libzfs
Make the cityhash code compile into libzfs, in preparation for the new
"zstream" command.

Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #10152
2020-03-27 09:11:22 -07:00
Ryan Moeller
f5f6fb03b7
Change default to overlay=on
Filesystems allow overlay mounts by default on FreeBSD and Linux.

Respect the native convention by switching the default to overlay=on,
while retaining the option to turn the property off for compatibility
with other operating systems' conventions.

Update documentation and tests accordingly.

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes #10030
2020-03-06 09:28:19 -08:00
Richard Laager
f244846462
Prefer org.openzfs for features and properties
Moving forward, we wish to use org.openzfs (no dash) rather than
org.open-zfs or org.zfsonlinux for feature GUIDs and property names.
The existing feature GUIDs cannot be changed.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Richard Laager <rlaager@wiktel.com>
Closes #10003
2020-02-18 09:36:50 -08:00
Christian Schwarz
a73f361fdb Implement bookmark copying
This feature allows copying existing bookmarks using

    zfs bookmark fs#target fs#newbookmark

There are some niche use cases for such functionality,
e.g. when using bookmarks as markers for replication progress.

Copying redaction bookmarks produces a normal bookmark that
cannot be used for redacted send (we are not duplicating
the redaction object).

ZCP support for bookmarking (both creation and copying) will be
implemented in a separate patch based on this work.

Overview:

- Terminology:
    - source = existing snapshot or bookmark
    - new/bmark = new bookmark
- Implement bookmark copying in `dsl_bookmark.c`
  - create new bookmark node
  - copy source's `zbn_phys` to new's `zbn_phys`
  - zero-out redaction object id in copy
- Extend existing bookmark ioctl nvlist schema to accept
  bookmarks as sources
  - => `dsl_bookmark_create_nvl_validate` is authoritative
- use `dsl_dataset_is_before` check for both snapshot
  and bookmark sources
- Adjust CLI
  - refactor shortname expansion logic in `zfs_do_bookmark`
- Update man pages
  - warn about redaction bookmark handling
- Add test cases
  - CLI
  - pyyzfs libzfs_core bindings

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Christian Schwarz <me@cschwarz.com>
Closes #9571
2020-02-11 13:19:12 -08:00
Ryan Moeller
8c4987c489
Restore aclmode and remove acltype on FreeBSD
This replaces the placeholder ZFS_PROP_PRIVATE with ZFS_PROP_ACLMODE,
matching what is done in the NFSv4 ACLs PR (#9709).

On FreeBSD we hide ZFS_PROP_ACLTYPE, while on Linux we hide
ZFS_PROP_ACLMODE.

The tests already assume this arrangement.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes #9913
2020-02-04 08:40:07 -08:00
Ryan Moeller
fe7c15985b
Left-align index props
Index type props display as strings, which should be aligned to the
left not to the right.

Before:
```
FreeBSD-13_0-CURRENT-r356528 ➜  ~ zfs list -ro name,aclmode,mountpoint
NAME        ACLMODE  MOUNTPOINT
p0      passthrough  /p0
p0/foo      discard  /p0/foo
```

After:
```
FreeBSD-13_0-CURRENT-r356528 ➜  ~ zfs list -ro name,aclmode,mountpoint
NAME    ACLMODE      MOUNTPOINT
p0      passthrough  /p0
p0/foo  discard      /p0/foo
```

Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes #9912
2020-01-31 08:55:51 -08:00
Christian Schwarz
3aea3c9d54 entity_namecheck: doc comment: include space as allowed character
The helper function valid_char already allows it but
the doc comment was out of date.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Christian Schwarz <me@cschwarz.com>
Closes #9879
2020-01-23 21:11:54 -08:00
Brian Behlendorf
70835c5b75
Unify target_cpu handling
Over the years several slightly different approaches were used
in the Makefiles to determine the target architecture.  This
change updates both the build system and Makefile to handle
this in a consistent fashion.

TARGET_CPU is set to i386, x86_64, powerpc, aarch6 or sparc64
and made available in the Makefiles to be used as appropriate.

Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9848
2020-01-17 12:40:09 -08:00
loli10K
c24fa4b19a Fix "zpool add -n" for dedup, special and log devices
For dedup, special and log devices "zpool add -n" does not print
correctly their vdev type:

~# zpool add -n pool dedup /tmp/dedup special /tmp/special log /tmp/log
would update 'pool' to the following configuration:
	pool
	  /tmp/normal
	  /tmp/dedup
	  /tmp/special
	  /tmp/log

This could lead storage administrators to modify their ZFS pools to
unexpected and unintended vdev configurations.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #9783 
Closes #9390
2020-01-06 15:40:06 -08:00
Matthew Macy
4bc721965f Add FreeBSD jail support hooks
Add the 'zfs jail/unjail' subcommands along with the relevant 
documentation from FreeBSD.  This feature is not supported on
Linux and still requires the match kernel ioctls which will
be included when the FreeBSD platform code is integrated.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9686
2019-12-11 11:58:37 -08:00
Matthew Macy
0dcef9b966 Disable sysfs feature checks on FreeBSD
The sysfs infrastructure for reporting supported features and
properties is Linux specific.  Disable it on FreeBSD until it can
be extended to be more portable.

Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9684
2019-12-06 09:44:29 -08:00
Matthew Macy
f95704ca5e Disable EDONR on FreeBSD
FreeBSD uses its own crypto framework in-kernel which, at this time,
has no EDONR implementation.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9664
2019-12-05 13:10:29 -08:00
Brian Behlendorf
624222ae31
Increase allowed 'special_small_blocks' maximum value
There may be circumstances where it's desirable that all blocks
in a specified dataset be stored on the special device.  Relax
the artificial 128K limit and allow the special_small_blocks
property to be set up to 1M.  When blocks >1MB have been enabled
via the zfs_max_recordsize module option, this limit is increased
accordingly.

Reviewed-by: Don Brady <don.brady@delphix.com>
Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9131
Closes #9355
2019-12-03 09:58:03 -08:00
Matthew Macy
b3673342c7 Wrap module_param_call() routines under __linux__
The module_param_call() functionality is currently still
Linux-specific and should be wrapped accordingly.

Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9666
2019-12-03 09:56:15 -08:00
Matthew Macy
74d1d74959 Move linux qsort def to platform header
Moving qsort to the platform header allows each platform to
provide an appropriate sorting implementation.

Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9663
2019-12-03 09:49:40 -08:00
Matthew Macy
4a2ed90013 Wrap Linux module macros
MODULE_VERSION is already defined on FreeBSD. Wrap all of the
used MODULE_* macros for the sake of consistency and portability.

Add a user space noop version to reduce the need for _KERNEL ifdefs.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9542
2019-11-01 10:41:03 -07:00
Romain Dolbeau
0b2a642351 Add AVX512BW variant of fletcher
It is much faster than AVX512F when byteswapping on Skylake-SP
and newer, as we can do the byteswap in a single vshufb instead
of many instructions.

Reviewed by: Gvozden Neskovic <neskovic@gmail.com>
Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Romain Dolbeau <romain.dolbeau@atos.net>
Closes #9517
2019-10-30 12:26:14 -07:00
Brian Behlendorf
10fa254539
Linux 4.14, 4.19, 5.0+ compat: SIMD save/restore
Contrary to initial testing we cannot rely on these kernels to
invalidate the per-cpu FPU state and restore the FPU registers.
Nor can we guarantee that the kernel won't modify the FPU state
which we saved in the task struck.

Therefore, the kfpu_begin() and kfpu_end() functions have been
updated to save and restore the FPU state using our own dedicated
per-cpu FPU state variables.

This has the additional advantage of allowing us to use the FPU
again in user threads.  So we remove the code which was added to
use task queues to ensure some functions ran in kernel threads.

Reviewed-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #9346
Closes #9403
2019-10-24 10:17:33 -07:00
Matthew Macy
bce795ad7a Remove linux/mod_compat.h from common code
It is no longer necessary; mod_compat.h is included from zfs_context.h.

Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9449
2019-10-11 10:10:20 -07:00
loli10K
715c996d3b Fix pool creation with feature@allocation_classes disabled
When "feature@allocation_classes" is not enabled on the pool no vdev
with "special" or "dedup" allocation type should be allowed to exist in
the vdev tree.

Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes #9427 
Closes #9429
2019-10-10 16:39:41 -07:00
Matthew Macy
03fdcb9adc Make module tunables cross platform
Adds ZFS_MODULE_PARAM to abstract module parameter
setting to operating systems other than Linux.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9230
2019-09-05 14:49:49 -07:00
Matthew Macy
006e9a4088 OpenZFS restructuring - move platform specific headers
Move platform specific Linux headers under include/os/linux/.
Update the build system accordingly to detect the platform.
This lays some of the initial groundwork to supporting building
for other platforms.

As part of this change it was necessary to create both a user
and kernel space sys/simd.h header which can be included in
either context.  No functional change, the source has been
refactored and the relevant #include's updated.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Signed-off-by: Matthew Macy <mmacy@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9198
2019-09-05 09:34:54 -07:00
Andrea Gelmini
9f5c1bc609 Fix typos in module/
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #9241
2019-08-30 14:32:18 -07:00
Sara Hartse
37f03da8ba Fast Clone Deletion
Deleting a clone requires finding blocks are clone-only, not shared
with the snapshot. This was done by traversing the entire block tree
which results in a large performance penalty for sparsely
written clones.

This is new method keeps track of clone blocks when they are
modified in a "Livelist" so that, when it’s time to delete,
the clone-specific blocks are already at hand.

We see performance improvements because now deletion work is
proportional to the number of clone-modified blocks, not the size
of the original dataset.

Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Sara Hartse <sara.hartse@delphix.com>
Closes #8416
2019-07-26 10:54:14 -07:00
Brian Behlendorf
8062b7686a
Minor style cleanup
Resolve an assortment of style inconsistencies including
use of white space, typos, capitalization, and line wrapping.
There is no functional change.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9030
2019-07-16 17:22:31 -07:00
Serapheim Dimitropoulos
93e28d661e Log Spacemap Project
= Motivation

At Delphix we've seen a lot of customer systems where fragmentation
is over 75% and random writes take a performance hit because a lot
of time is spend on I/Os that update on-disk space accounting metadata.
Specifically, we seen cases where 20% to 40% of sync time is spend
after sync pass 1 and ~30% of the I/Os on the system is spent updating
spacemaps.

The problem is that these pools have existed long enough that we've
touched almost every metaslab at least once, and random writes
scatter frees across all metaslabs every TXG, thus appending to
their spacemaps and resulting in many I/Os. To give an example,
assuming that every VDEV has 200 metaslabs and our writes fit within
a single spacemap block (generally 4K) we have 200 I/Os. Then if we
assume 2 levels of indirection, we need 400 additional I/Os and
since we are talking about metadata for which we keep 2 extra copies
for redundancy we need to triple that number, leading to a total of
1800 I/Os per VDEV every TXG.

We could try and decrease the number of metaslabs so we have less
I/Os per TXG but then each metaslab would cover a wider range on
disk and thus would take more time to be loaded in memory from disk.
In addition, after it's loaded, it's range tree would consume more
memory.

Another idea would be to just increase the spacemap block size
which would allow us to fit more entries within an I/O block
resulting in fewer I/Os per metaslab and a speedup in loading time.
The problem is still that we don't deal with the number of I/Os
going up as the number of metaslabs is increasing and the fact
is that we generally write a lot to a few metaslabs and a little
to the rest of them. Thus, just increasing the block size would
actually waste bandwidth because we won't be utilizing our bigger
block size.

= About this patch

This patch introduces the Log Spacemap project which provides the
solution to the above problem while taking into account all the
aforementioned tradeoffs. The details on how it achieves that can
be found in the references sections below and in the code (see
Big Theory Statement in spa_log_spacemap.c).

Even though the change is fairly constraint within the metaslab
and lower-level SPA codepaths, there is a side-change that is
user-facing. The change is that VDEV IDs from VDEV holes will no
longer be reused. To give some background and reasoning for this,
when a log device is removed and its VDEV structure was replaced
with a hole (or was compacted; if at the end of the vdev array),
its vdev_id could be reused by devices added after that. Now
with the pool-wide space maps recording the vdev ID, this behavior
can cause problems (e.g. is this entry referring to a segment in
the new vdev or the removed log?). Thus, to simplify things the
ID reuse behavior is gone and now vdev IDs for top-level vdevs
are truly unique within a pool.

= Testing

The illumos implementation of this feature has been used internally
for a year and has been in production for ~6 months. For this patch
specifically there don't seem to be any regressions introduced to
ZTS and I have been running zloop for a week without any related
problems.

= Performance Analysis (Linux Specific)

All performance results and analysis for illumos can be found in
the links of the references. Redoing the same experiments in Linux
gave similar results. Below are the specifics of the Linux run.

After the pool reached stable state the percentage of the time
spent in pass 1 per TXG was 64% on average for the stock bits
while the log spacemap bits stayed at 95% during the experiment
(graph: sdimitro.github.io/img/linux-lsm/PercOfSyncInPassOne.png).

Sync times per TXG were 37.6 seconds on average for the stock
bits and 22.7 seconds for the log spacemap bits (related graph:
sdimitro.github.io/img/linux-lsm/SyncTimePerTXG.png). As a result
the log spacemap bits were able to push more TXGs, which is also
the reason why all graphs quantified per TXG have more entries for
the log spacemap bits.

Another interesting aspect in terms of txg syncs is that the stock
bits had 22% of their TXGs reach sync pass 7, 55% reach sync pass 8,
and 20% reach 9. The log space map bits reached sync pass 4 in 79%
of their TXGs, sync pass 7 in 19%, and sync pass 8 at 1%. This
emphasizes the fact that not only we spend less time on metadata
but we also iterate less times to convergence in spa_sync() dirtying
objects.
[related graphs:
stock- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGStock.png
lsm- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGLSM.png]

Finally, the improvement in IOPs that the userland gains from the
change is approximately 40%. There is a consistent win in IOPS as
you can see from the graphs below but the absolute amount of
improvement that the log spacemap gives varies within each minute
interval.
sdimitro.github.io/img/linux-lsm/StockVsLog3Days.png
sdimitro.github.io/img/linux-lsm/StockVsLog10Hours.png

= Porting to Other Platforms

For people that want to port this commit to other platforms below
is a list of ZoL commits that this patch depends on:

Make zdb results for checkpoint tests consistent
db587941c5

Update vdev_is_spacemap_addressable() for new spacemap encoding
419ba59145

Simplify spa_sync by breaking it up to smaller functions
8dc2197b7b

Factor metaslab_load_wait() in metaslab_load()
b194fab0fb

Rename range_tree_verify to range_tree_verify_not_present
df72b8bebe

Change target size of metaslabs from 256GB to 16GB
c853f382db

zdb -L should skip leak detection altogether
21e7cf5da8

vs_alloc can underflow in L2ARC vdevs
7558997d2f

Simplify log vdev removal code
6c926f426a

Get rid of space_map_update() for ms_synced_length
425d3237ee

Introduce auxiliary metaslab histograms
928e8ad47d

Error path in metaslab_load_impl() forgets to drop ms_sync_lock
8eef997679

= References

Background, Motivation, and Internals of the Feature
- OpenZFS 2017 Presentation:
youtu.be/jj2IxRkl5bQ
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemaps-project

Flushing Algorithm Internals & Performance Results
(Illumos Specific)
- Blogpost:
sdimitro.github.io/post/zfs-lsm-flushing/
- OpenZFS 2018 Presentation:
youtu.be/x6D2dHRjkxw
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemap-flushing-algorithm

Upstream Delphix Issues:
DLPX-51539, DLPX-59659, DLPX-57783, DLPX-61438, DLPX-41227, DLPX-59320
DLPX-63385

Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #8442
2019-07-16 10:11:49 -07:00
Brian Behlendorf
e5db313494
Linux 5.0 compat: SIMD compatibility
Restore the SIMD optimization for 4.19.38 LTS, 4.14.120 LTS,
and 5.0 and newer kernels.  This is accomplished by leveraging
the fact that by definition dedicated kernel threads never need
to concern themselves with saving and restoring the user FPU state.
Therefore, they may use the FPU as long as we can guarantee user
tasks always restore their FPU state before context switching back
to user space.

For the 5.0 and 5.1 kernels disabling preemption and local
interrupts is sufficient to allow the FPU to be used.  All non-kernel
threads will restore the preserved user FPU state.

For 5.2 and latter kernels the user FPU state restoration will be
skipped if the kernel determines the registers have not changed.
Therefore, for these kernels we need to perform the additional
step of saving and restoring the FPU registers.  Invalidating the
per-cpu global tracking the FPU state would force a restore but
that functionality is private to the core x86 FPU implementation
and unavailable.

In practice, restricting SIMD to kernel threads is not a major
restriction for ZFS.  The vast majority of SIMD operations are
already performed by the IO pipeline.  The remaining cases are
relatively infrequent and can be handled by the generic code
without significant impact.  The two most noteworthy cases are:

  1) Decrypting the wrapping key for an encrypted dataset,
     i.e. `zfs load-key`.  All other encryption and decryption
     operations will use the SIMD optimized implementations.

  2) Generating the payload checksums for a `zfs send` stream.

In order to avoid making any changes to the higher layers of ZFS
all of the `*_get_ops()` functions were updated to take in to
consideration the calling context.  This allows for the fastest
implementation to be used as appropriate (see kfpu_allowed()).

The only other notable instance of SIMD operations being used
outside a kernel thread was at module load time.  This code
was moved in to a taskq in order to accommodate the new kernel
thread restriction.

Finally, a few other modifications were made in order to further
harden this code and facilitate testing.  They include updating
each implementations operations structure to be declared as a
constant.  And allowing "cycle" to be set when selecting the
preferred ops in the kernel as well as user space.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8754 
Closes #8793 
Closes #8965
2019-07-12 09:31:20 -07:00
Matthew Ahrens
59ec30a329 Remove code for zfs remap
The "zfs remap" command was disabled by
6e91a72fe3, because it has little utility
and introduced some tricky bugs.  This commit removes the code for it,
the associated ZFS_IOC_REMAP ioctl, and tests.

Note that the ioctl and property will remain, but have no functionality.
This allows older software to fail gracefully if it attempts to use
these, and avoids a backwards incompatibility that would be introduced if
we renumbered the later ioctls/props.

Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #8944
2019-06-24 16:44:01 -07:00
Matthew Ahrens
050d720c43 Remove dedupditto functionality
If dedup is in use, the `dedupditto` property can be set, causing ZFS to
keep an extra copy of data that is referenced many times (>100x).  The
idea was that this data is more important than other data and thus we
want to be really sure that it is not lost if the disk experiences a
small amount of random corruption.

ZFS (and system administrators) rely on the pool-level redundancy to
protect their data (e.g. mirroring or RAIDZ).  Since the user/sysadmin
doesn't have control over what data will be offered extra redundancy by
dedupditto, this extra redundancy is not very useful.  The bulk of the
data is still vulnerable to loss based on the pool-level redundancy.
For example, if particle strikes corrupt 0.1% of blocks, you will either
be saved by mirror/raidz, or you will be sad.  This is true even if
dedupditto saved another 0.01% of blocks from being corrupted.

Therefore, the dedupditto functionality is rarely enabled (i.e. the
property is rarely set), and it fulfills its promise of increased
redundancy even more rarely.

Additionally, this feature does not work as advertised (on existing
releases), because scrub/resilver did not repair the extra (dedupditto)
copy (see https://github.com/zfsonlinux/zfs/pull/8270).

In summary, this seldom-used feature doesn't work, and even if it did it
wouldn't provide useful data protection.  It has a non-trivial
maintenance burden (again see https://github.com/zfsonlinux/zfs/pull/8270).

We should remove the dedupditto functionality.  For backwards
compatibility with the existing CLI, "zpool set dedupditto" will still
"succeed" (exit code zero), but won't have any effect.  For backwards
compatibility with existing pools that had dedupditto enabled at some
point, the code will still be able to understand dedupditto blocks and
free them when appropriate.  However, ZFS won't write any new dedupditto
blocks.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Alek Pinchuk <apinchuk@datto.com>
Issue #8270 
Closes #8310
2019-06-19 14:54:02 -07:00
Paul Dagnelie
30af21b025 Implement Redacted Send/Receive
Redacted send/receive allows users to send subsets of their data to 
a target system. One possible use case for this feature is to not 
transmit sensitive information to a data warehousing, test/dev, or 
analytics environment. Another is to save space by not replicating 
unimportant data within a given dataset, for example in backup tools 
like zrepl.

Redacted send/receive is a three-stage process. First, a clone (or 
clones) is made of the snapshot to be sent to the target. In this 
clone (or clones), all unnecessary or unwanted data is removed or
modified. This clone is then snapshotted to create the "redaction 
snapshot" (or snapshots). Second, the new zfs redact command is used 
to create a redaction bookmark. The redaction bookmark stores the 
list of blocks in a snapshot that were modified by the redaction 
snapshot(s). Finally, the redaction bookmark is passed as a parameter 
to zfs send. When sending to the snapshot that was redacted, the
redaction bookmark is used to filter out blocks that contain sensitive 
or unwanted information, and those blocks are not included in the send 
stream.  When sending from the redaction bookmark, the blocks it 
contains are considered as candidate blocks in addition to those 
blocks in the destination snapshot that were modified since the 
creation_txg of the redaction bookmark.  This step is necessary to 
allow the target to rehydrate data in the case where some blocks are 
accidentally or unnecessarily modified in the redaction snapshot.

The changes to bookmarks to enable fast space estimation involve 
adding deadlists to bookmarks. There is also logic to manage the 
life cycles of these deadlists.

The new size estimation process operates in cases where previously 
an accurate estimate could not be provided. In those cases, a send 
is performed where no data blocks are read, reducing the runtime 
significantly and providing a byte-accurate size estimate.

Reviewed-by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Prashanth Sreenivasa <pks@delphix.com>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Chris Williamson <chris.williamson@delphix.com>
Reviewed-by: Pavel Zhakarov <pavel.zakharov@delphix.com>
Reviewed-by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #7958
2019-06-19 09:48:12 -07:00
Tulsi Jain
9c7da9a95a Restrict filesystem creation if name referred either '.' or '..'
This change restricts filesystem creation if the given name
contains either '.' or '..'

Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Signed-off-by: TulsiJain <tulsi.jain@delphix.com>
Closes #8842 
Closes #8564
2019-06-13 08:56:15 -07:00
Brian Behlendorf
1b939560be
Add TRIM support
UNMAP/TRIM support is a frequently-requested feature to help
prevent performance from degrading on SSDs and on various other
SAN-like storage back-ends.  By issuing UNMAP/TRIM commands for
sectors which are no longer allocated the underlying device can
often more efficiently manage itself.

This TRIM implementation is modeled on the `zpool initialize`
feature which writes a pattern to all unallocated space in the
pool.  The new `zpool trim` command uses the same vdev_xlate()
code to calculate what sectors are unallocated, the same per-
vdev TRIM thread model and locking, and the same basic CLI for
a consistent user experience.  The core difference is that
instead of writing a pattern it will issue UNMAP/TRIM commands
for those extents.

The zio pipeline was updated to accommodate this by adding a new
ZIO_TYPE_TRIM type and associated spa taskq.  This new type makes
is straight forward to add the platform specific TRIM/UNMAP calls
to vdev_disk.c and vdev_file.c.  These new ZIO_TYPE_TRIM zios are
handled largely the same way as ZIO_TYPE_READs or ZIO_TYPE_WRITEs.
This makes it possible to largely avoid changing the pipieline,
one exception is that TRIM zio's may exceed the 16M block size
limit since they contain no data.

In addition to the manual `zpool trim` command, a background
automatic TRIM was added and is controlled by the 'autotrim'
property.  It relies on the exact same infrastructure as the
manual TRIM.  However, instead of relying on the extents in a
metaslab's ms_allocatable range tree, a ms_trim tree is kept
per metaslab.  When 'autotrim=on', ranges added back to the
ms_allocatable tree are also added to the ms_free tree.  The
ms_free tree is then periodically consumed by an autotrim
thread which systematically walks a top level vdev's metaslabs.

Since the automatic TRIM will skip ranges it considers too small
there is value in occasionally running a full `zpool trim`.  This
may occur when the freed blocks are small and not enough time
was allowed to aggregate them.  An automatic TRIM and a manual
`zpool trim` may be run concurrently, in which case the automatic
TRIM will yield to the manual TRIM.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Tim Chase <tim@chase2k.com>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Contributions-by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Contributions-by: Tim Chase <tim@chase2k.com>
Contributions-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8419 
Closes #598
2019-03-29 09:13:20 -07:00
Tom Caputi
f00ab3f22c Detect and prevent mixed raw and non-raw sends
Currently, there is an issue in the raw receive code where
raw receives are allowed to happen on top of previously
non-raw received datasets. This is a problem because the
source-side dataset doesn't know about how the blocks on
the destination were encrypted. As a result, any MAC in
the objset's checksum-of-MACs tree that is a parent of both
blocks encrypted on the source and blocks encrypted by the
destination will be incorrect. This will result in
authentication errors when we decrypt the dataset.

This patch fixes this issue by adding a new check to the
raw receive code. The code now maintains an "IVset guid",
which acts as an identifier for the set of IVs used to
encrypt a given snapshot. When a snapshot is raw received,
the destination snapshot will take this value from the
DRR_BEGIN payload. Non-raw receives and normal "zfs snap"
operations will cause ZFS to generate a new IVset guid.
When a raw incremental stream is received, ZFS will check
that the "from" IVset guid in the stream matches that of
the "from" destination snapshot. If they do not match, the
code will error out the receive, preventing the problem.

This patch requires an on-disk format change to add the
IVset guids to snapshots and bookmarks. As a result, this
patch has errata handling and a tunable to help affected
users resolve the issue with as little interruption as
possible.

Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #8308
2019-03-13 11:00:43 -07:00
Tom Caputi
579ce7c5ae Add bookmark v2 on-disk feature
This patch adds the bookmark v2 feature to the on-disk format. This
feature will be needed for the upcoming redacted sends and for an
upcoming fix that for raw receives. The feature is not currently
used by any code and thus this change is a no-op, aside from the
fact that the user can now enable the feature.

Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Issue #8308
2019-03-13 10:58:39 -07:00
Tony Hutter
77e50c3070 Linux 5.0 compat: access_ok() drops 'type' parameter
access_ok no longer needs a 'type' parameter in the 5.0 kernel.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #8261
2019-01-28 10:11:10 -08:00
Brian Behlendorf
0b8e4418b6
Add zfs module feature and property compatibility
This change is required to ease the transition when upgrading
from 0.7.x to 0.8.x.  It allows 0.8.x user space utilities to
remain compatible with 0.7.x and older kernel modules.

Reviewed-by: Don Brady <don.brady@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8231
2019-01-03 15:19:37 -08:00
Brian Behlendorf
c5eea0ab9c
Fix 'zpool list -v' alignment
The verbose output of 'zpool list' was not correctly aligned due
to differences in the vdev name lengths.  Minimally update the
code the correct the alignment using the same strategy employed
by 'zpool status'.

Missing dashes were added for the empty defaults columns, and
the vdev state is now printed for all vdevs.

Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #7308 
Closes #8147
2018-12-04 10:17:54 -08:00
Tom Caputi
80a91e7469 Defer new resilvers until the current one ends
Currently, if a resilver is triggered for any reason while an
existing one is running, zfs will immediately restart the existing
resilver from the beginning to include the new drive. This causes
problems for system administrators when a drive fails while another
is already resilvering. In this case, the optimal thing to do to
reduce risk of data loss is to wait for the current resilver to end
before immediately replacing the second failed drive, which allows
the system to operate with two incomplete drives for the minimum
amount of time.

This patch introduces the resilver_defer feature that essentially
does this for the admin without forcing them to wait and monitor
the resilver manually. The change requires an on-disk feature
since we must mark drives that are part of a deferred resilver in
the vdev config to ensure that we do not assume they are done
resilvering when an existing resilver completes.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: @mmaybee 
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes #7732
2018-10-18 21:06:18 -07:00
Paul Dagnelie
d52d80b700 Add types to featureflags in zfs
The boolean featureflags in use thus far in ZFS are extremely useful,
but because they take advantage of the zap layer, more interesting data
than just a true/false value can be stored in a featureflag. In redacted
send/receive, this is used to store the list of redaction snapshots for
a redacted dataset.

This change adds the ability for ZFS to store types other than a boolean
in a featureflag. The only other implemented type is a uint64_t array.
It also modifies the interfaces around dataset features to accomodate
the new capabilities, and adds a few new functions to increase
encapsulation.

This functionality will be used by the Redacted Send/Receive feature.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #7981
2018-10-16 11:15:04 -07:00
ilbsmart
779a6c0bf6 deadlock between mm_sem and tx assign in zfs_write() and page fault
The bug time sequence:
1. thread #1, `zfs_write` assign a txg "n".
2. In a same process, thread #2, mmap page fault (which means the
   `mm_sem` is hold) occurred, `zfs_dirty_inode` open a txg failed,
   and wait previous txg "n" completed.
3. thread #1 call `uiomove` to write, however page fault is occurred
   in `uiomove`, which means it need `mm_sem`, but `mm_sem` is hold by
   thread #2, so it stuck and can't complete,  then txg "n" will
   not complete.

So thread #1 and thread #2 are deadlocked.

Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Grady Wong <grady.w@xtaotech.com>
Closes #7939
2018-10-16 11:11:24 -07:00
Don Brady
73a5ec30bf Fix in-kernel sysfs entries
The recent sysfs zfs properties feature breaks the in-kernel
builds of zfs (sans module).  When not built as a module add
the sysfs entries under /sys/fs/zfs/.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes #7868 
Closes #7872
2018-09-06 21:44:52 -07:00
Don Brady
cc99f275a2 Pool allocation classes
Allocation Classes add the ability to have allocation classes in a
pool that are dedicated to serving specific block categories, such
as DDT data, metadata, and small file blocks. A pool can opt-in to
this feature by adding a 'special' or 'dedup' top-level VDEV.

Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Alek Pinchuk <apinchuk@datto.com>
Reviewed-by: Håkan Johansson <f96hajo@chalmers.se>
Reviewed-by: Andreas Dilger <andreas.dilger@chamcloud.com>
Reviewed-by: DHE <git@dehacked.net>
Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed-by: Gregor Kopka <gregor@kopka.net>
Reviewed-by: Kash Pande <kash@tripleback.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes #5182
2018-09-05 18:33:36 -07:00
Don Brady
e8bcb693d6 Add zfs module feature and property info to sysfs
This extends our sysfs '/sys/module/zfs' entry to include feature 
and property attributes. The primary consumer of this information 
is user processes, like the zfs CLI, that need to know what the 
current loaded ZFS module supports. The libzfs binary will consult 
this information when instantiating the zfs and zpool property 
tables and the pool features table.

This introduces 4 kernel objects (dirs) into '/sys/module/zfs'
with corresponding attributes (files):
  features.runtime
  features.pool
  properties.dataset
  properties.pool

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes #7706
2018-09-02 12:09:53 -07:00
Serapheim Dimitropoulos
a448a2557e Introduce read/write kstats per dataset
The following patch introduces a few statistics on reads and writes
grouped by dataset. These statistics are implemented as kstats
(backed by aggregate sums for performance) and can be retrieved by
using the dataset objset ID number. The motivation for this change is
to provide some preliminary analytics on dataset usage/performance.

Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes #7705
2018-08-20 09:52:37 -07:00
Matthew Ahrens
2e5dc449c1 OpenZFS 9337 - zfs get all is slow due to uncached metadata
This project's goal is to make read-heavy channel programs and zfs(1m)
administrative commands faster by caching all the metadata that they will
need in the dbuf layer. This will prevent the data from being evicted, so
that any future call to i.e. zfs get all won't have to go to disk (very
much). There are two parts:

The dbuf_metadata_cache. We identify what to put into the cache based on
the object type of each dbuf.  Caching objset properties os
{version,normalization,utf8only,casesensitivity} in the objset_t. The reason
these needed to be cached is that although they are queried frequently,
they aren't stored in a dbuf type which we can easily recognize and cache in
the dbuf layer; instead, we have to explicitly store them. There's already
existing infrastructure for maintaining cached properties in the objset
setup code, so I simply used that.

Performance Testing:

 - Disabled kmem_flags
 - Tuned dbuf_cache_max_bytes very low (128K)
 - Tuned zfs_arc_max very low (64M)

Created test pool with 400 filesystems, and 100 snapshots per filesystem.
Later on in testing, added 600 more filesystems (with no snapshots) to make
sure scaling didn't look different between snapshots and filesystems.

Results:

    | Test                   | Time (trunk / diff) | I/Os (trunk / diff) |
    +------------------------+---------------------+---------------------+
    | zpool import           |     0:05 / 0:06     |    12.9k / 12.9k    |
    | zfs get all (uncached) |     1:36 / 0:53     |    16.7k / 5.7k     |
    | zfs get all (cached)   |     1:36 / 0:51     |    16.0k / 6.0k     |

Authored by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Thomas Caputi <tcaputi@datto.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Richard Lowe <richlowe@richlowe.net>
Ported-by: Alek Pinchuk <apinchuk@datto.com>
Signed-off-by: Alek Pinchuk <apinchuk@datto.com>

OpenZFS-issue: https://illumos.org/issues/9337
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/7dec52f
Closes #7668
2018-07-12 10:49:27 -07:00
Serapheim Dimitropoulos
a7ed98d8b5 OpenZFS 9330 - stack overflow when creating a deeply nested dataset
Datasets that are deeply nested (~100 levels) are impractical. We just
put a limit of 50 levels to newly created datasets. Existing datasets
should work without a problem.

The problem can be seen by attempting to create a dataset using the -p
option with many levels:

    panic[cpu0]/thread=ffffff01cd282c20: BAD TRAP: type=8 (#df Double fault) rp=ffffffff

    fffffffffbc3aa60 unix:die+100 ()
    fffffffffbc3ab70 unix:trap+157d ()
    ffffff00083d7020 unix:_patch_xrstorq_rbx+196 ()
    ffffff00083d7050 zfs:dbuf_rele+2e ()
    ...
    ffffff00083d7080 zfs:dsl_dir_close+32 ()
    ffffff00083d70b0 zfs:dsl_dir_evict+30 ()
    ffffff00083d70d0 zfs:dbuf_evict_user+4a ()
    ffffff00083d7100 zfs:dbuf_rele_and_unlock+87 ()
    ffffff00083d7130 zfs:dbuf_rele+2e ()
    ... The block above repeats once per directory in the ...
    ... create -p command, working towards the root ...
    ffffff00083db9f0 zfs:dsl_dataset_drop_ref+19 ()
    ffffff00083dba20 zfs:dsl_dataset_rele+42 ()
    ffffff00083dba70 zfs:dmu_objset_prefetch+e4 ()
    ffffff00083dbaa0 zfs:findfunc+23 ()
    ffffff00083dbb80 zfs:dmu_objset_find_spa+38c ()
    ffffff00083dbbc0 zfs:dmu_objset_find+40 ()
    ffffff00083dbc20 zfs:zfs_ioc_snapshot_list_next+4b ()
    ffffff00083dbcc0 zfs:zfsdev_ioctl+347 ()
    ffffff00083dbd00 genunix:cdev_ioctl+45 ()
    ffffff00083dbd40 specfs:spec_ioctl+5a ()
    ffffff00083dbdc0 genunix:fop_ioctl+7b ()
    ffffff00083dbec0 genunix:ioctl+18e ()
    ffffff00083dbf10 unix:brand_sys_sysenter+1c9 ()

Porting notes:
* Added zfs_max_dataset_nesting module option with documentation.
* Updated zfs_rename_014_neg.ksh for Linux.
* Increase the zfs.sh stack warning to 15K.  Enough time has passed
  that 16K can be reasonably assumed to be the default value.  It
  was increased in the 3.15 kernel released in June of 2014.

Authored by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Garrett D'Amore <garrett@damore.org>

OpenZFS-issue: https://www.illumos.org/issues/9330
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/757a75a
Closes #7681
2018-07-09 13:02:50 -07:00
Serapheim Dimitropoulos
4d044c4c1d OpenZFS 9238 - ZFS Spacemap Encoding V2
Motivation
==========

The current space map encoding has the following disadvantages:
[1] Assuming 512 sector size each entry can represent at most 16MB for a segment.
    This makes the encoding very inefficient for large regions of space.
[2] As vdev-wide space maps have started to be used by new features (i.e.
    device removal, zpool checkpoint) we've started imposing limits in the
    vdevs that can be used with them based on the maximum addressable offset
    (currently 64PB for a top-level vdev).

New encoding
============

The layout can be found at space_map.h and it remains backwards compatible with
the old one. The introduced two-word entry format, besides extending the limits
imposed by the single-entry layout, also includes a vdev field and some extra
padding after its prefix.

The extra padding after the prefix should is reserved for future usage (e.g.
new prefixes for future encodings or new fields for flags). The new vdev field
not only makes the space maps more self-descriptive, but also opens the doors
for pool-wide space maps (expected to be used in the log spacemap project).

One final important note is that the number of bits used for vdevs is reduced
to 24 bits for blkptrs. That was decided as we don't know of any setups that
use more than 16M vdevs for the time being and we wanted to fit the vdev field
in the space map. In addition that gives us some extra bits in dva_t.

Other references:
=================

The new encoding is also discussed towards the end of the Log Space Map
presentation from 2017's OpenZFS summit.
Link: https://www.youtube.com/watch?v=jj2IxRkl5bQ

Authored by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <gwilson@zfsmail.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Gordon Ross <gwr@nexenta.com>
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>

OpenZFS-commit: https://github.com/openzfs/openzfs/commit/90a56e6d
OpenZFS-issue: https://www.illumos.org/issues/9238
Closes #7665
2018-07-05 12:02:34 -07:00