MFC r322245,r329717: MFV r322242: 8373 TXG_WAIT in ZIL commit path

MFC r322245: MFV r322242: 8373 TXG_WAIT in ZIL commit path
MFC r329717: MFV r329715: 8997 ztest assertion failure in zil_lwb_write_issue

MFC r305340: MFC r305337:
7004 dmu_tx_hold_zap() does dnode_hold() 7x on same object

Using a benchmark which has 32 threads creating 2 million files in the
same directory, on a machine with 16 CPU cores, I observed poor
performance. I noticed that dmu_tx_hold_zap() was using about 30% of
all CPU, and doing dnode_hold() 7 times on the same object (the ZAP
object that is being held).

dmu_tx_hold_zap() keeps a hold on the dnode_t the entire time it is
running, in dmu_tx_hold_t:txh_dnode, so it would be nice to use the
dnode_t that we already have in hand, rather than repeatedly calling
dnode_hold(). To do this, we need to pass the dnode_t down through
all the intermediate calls that dmu_tx_hold_zap() makes, making these
routines take the dnode_t* rather than an objset_t* and a uint64_t
object number. In particular, the following routines will need to have
analogous *_by_dnode() variants created:

dmu_buf_hold_noread()
dmu_buf_hold()
zap_lookup()
zap_lookup_norm()
zap_count_write()
zap_lockdir()
zap_count_write()

This can improve performance on the benchmark described above by 100%,
from 30,000 file creations per second to 60,000. (This improvement is on
top of that provided by working around the object allocation issue. Peak
performance of ~90,000 creations per second was observed with 8 CPUs;
adding CPUs past that decreased performance due to lock contention.) The
CPU used by dmu_tx_hold_zap() was reduced by 88%, from 340 CPU-seconds
to 40 CPU-seconds.

Sponsored by: Intel Corp.

Closes #109

Reviewed by: Steve Gonczi <steve.gonczi@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Ned Bass <bass6@llnl.gov>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Author: Matthew Ahrens <mahrens@delphix.com>

openzfs/openzfs@d3e523d489a169ab36f9ec1b2a111a60a5563a9f

MFC r305338: MFV r305335: 7003 zap_lockdir() should tag hold

zap_lockdir() / zap_unlockdir() should take a "void *tag" argument which
tags the hold on the zap. This will help diagnose programming errors
which misuse the hold on the ZAP.

Sponsored by: Intel Corp.

Closes #108

Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Steve Gonczi <steve.gonczi@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Author: Matthew Ahrens <mahrens@delphix.com>

openzfs/openzfs@0780b3eab5a2c13e04328b39ecd2a6d0d3c4f7cb

MFC r305209: MFV r302660: 6314 buffer overflow in dsl_dataset_name

illumos/illumos-gate@9adfa60d484ce2435f5af77cc99dcd4e692b6660
https://github.com/illumos/illumos-gate/commit/9adfa60d484ce2435f5af77cc99dcd4e6
92b6660

https://www.illumos.org/issues/6314
Callers of dsl_dataset_name pass a buffer of size ZFS_MAXNAMELEN, but
dsl_dataset_name copies the datasets' name PLUS the snapshot name to it,
resulting in a max of 2 * ZFS_MAXNAMELEN + '@'.

Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Igor Kozhukhov <ikozhukhov@gmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Matthew Ahrens <mahrens@delphix.com>

MFC r296519: MFV r296518: 5027 zfs large block support (add copyright)

Author: Matthew Ahrens <matt@mahrens.org>

illumos/illumos-gate@c3d26abc9ee97b4f60233556aadeb57e0bd30bb9

MFC r277300 (by smh): Mechanically convert cddl sun #ifdef's to illumos

Since the upstream for cddl code is now illumos not sun, mechanically
convert all sun #ifdef's to illumos #ifdef's which have been used in all
newer code for some time.

Also do a manual pass to correct the use if #ifdef comments as per style(9)
as well as few uses of #if defined(__FreeBSD__) vs #ifndef illumos.

MFC r289422:
4185 add new cryptographic checksums to ZFS: SHA-512, Skein, Edon-R

Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Matthew Ahrens <mahrens@delphix.com>

illumos/illumos-gate@45818ee124adeaaf947698996b4f4c722afc6d1f

This is only a partial merge of respective ZFS infrastructure changes.
At this moment FreeBSD kernel has no those crypto algorithms, so the
parts of the code to enable them are commented out. When they are
implemented, it will be trivial to plug them in.

MFC r287702: 5987 zfs prefetch code needs work

Rewrite the ZFS prefetch code to detect only forward, sequential
streams.

The following kstats have been added:

kstat.zfs.misc.arcstats.sync_wait_for_async

How many sync reads have waited for async read
to complete. (less is better)

kstat.zfs.misc.arcstats.demand_hit_predictive_prefetch

How many demand read didn't have to wait for I/O
because of predictive prefetch. (more is better)

zfetch kstats have been similified to hits, misses, and max_streams,
with max_streams representing times when we were not able to create
new stream because we already have the maximum number of sequences
for a file.

The sysctl variable/loader tunable vfs.zfs.zfetch.block_cap have been
replaced by vfs.zfs.zfetch.max_distance, which controls maximum bytes
to prefetch per stream.

illumos/illumos-gate@cf6106c8a0d6598b045811f9650d66e07eb332af

Illumos ZFS issues:

5987 zfs prefetch code needs work
https://www.illumos.org/issues/5987

MFC r287103 (by avg): 5692 expose the number of hole blocks in a file

FreeBSD porting notes:
- only kernel-side changes are merged
- the new ioctl is not actually implemented yet
- thus, the goal is to synchronize DMU code

illumos/illumos-gate@2bcf0248e992f292c7b814458bcdce2f004925d6

https://www.illumos.org/issues/5692
we would like to expose the number of hole (sparse) blocks in a file.
this can be useful to for example if you want to fill in the holes with
some data; knowing the number of holes in advances allows you to report
progress on hole filling. We could use SEEK_HOLE to do that but it would
be O(n) where n is the number of holes present in the file.

Author: Max Grossman <max.grossman@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Boris Protopopov <bprotopopov@hotmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>

Fix r288549 build on stable.

For some reason this (odd) code builds on head, but not on stable.

MFC r286705: 5960 zfs recv should prefetch indirect blocks
5925 zfs receive -o origin=

Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Author: Paul Dagnelie <pcd@delphix.com>

While running 'zfs recv' we noticed that every 128th 8K block required a
read. We were seeing that restore_write() was calling dmu_tx_hold_write()
and the indirect block was not cached. We should prefetch upcoming indirect
blocks to avoid having to go to disk and blocking the restore_write().

Allow an incremental send stream to be received as a clone, even if the
stream does not mark it as a clone.

MFC r286686: 5269 zpool import slow

illumos/illumos-gate@12380e1e701fda28c9e9f32d01cafb54af279eb5

https://www.illumos.org/issues/5269
When importing a pool (at boot or with zpool import) with many
filesystem, the process can take minutes. It doesn't matter whether
the pool has been exported cleanly or uncleanly. The problem is that
each dataset has its own log chain. On import, all datasets have to be
checked if there are logs to replay. The idea is to speed up this
process by paralellizing it.

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Arne Jansen <jansen@webgods.de>

MFC r286575: 5056 ZFS deadlock on db_mtx and dn_holds

Reviewed by: Will Andrews <willa@spectralogic.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Justin Gibbs <justing@spectralogic.com>

illumos/illumos-gate@bc9014e6a81272073b9854d9f65dd59e18d18c35

MFC r286541: 5531 NULL pointer dereference in dsl_prop_get_ds()

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Justin T. Gibbs <justing@spectralogic.com>

illumos/illumos-gate@e57a022b8f718889ffa92adbde47a8f08abcdb25

MFC r275782: MFV r275551:

Remove "dbuf phys" db->db_data pointer aliases.

Use function accessors that cast db->db_data to the appropriate
"phys" type, removing the need for clients of the dmu buf user
API to keep properly typed pointer aliases to db->db_data in order
to conveniently access their data.

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_leaf.c:
In zap_leaf() and zap_leaf_byteswap, now that the pointer alias
field l_phys has been removed, use the db_data field in an on
stack dmu_buf_t to point to the leaf's phys data.

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c:
Remove the db_user_data_ptr_ptr field from dbuf and all logic
to maintain it.

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dnode.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dbuf.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c:
Modify the DMU buf user API to remove the ability to specify
a db_data aliasing pointer (db_user_data_ptr_ptr).

cddl/contrib/opensolaris/cmd/zdb/zdb.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_diff.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_traverse.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_tx.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_bookmark.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deadlist.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deleg.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_prop.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_synctask.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_userhold.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_history.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_leaf.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_impl.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_leaf.h:
Create and use the new "phys data" accessor functions
dsl_dir_phys(), dsl_dataset_phys(), zap_m_phys(),
zap_f_phys(), and zap_leaf_phys().

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_impl.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_leaf.h:
Remove now unused "phys pointer" aliases to db->db_data
from clients of the DMU buf user API.

Illumos issue:
5314 Remove "dbuf phys" db->db_data pointer aliases in ZFS

MFC r274337,r274673,274681,r275515:

ZFS large block support. The default recordsize remains at 128KB.

A new tunable/sysctl variable, vfs.zfs.max_recordsize is added to
allow adjusting the permitted maximum record size, or
zfs_max_recordsize, with a default of 1MB. ZFS will not allow
setting recordsize greater than zfs_max_recordsize as a safety
belt, because larger recordsize means greater read and write
latency and more memory usage.

Please note that booting from datasets that have recordsize greater
than 128KB is not supported (but it's Okay to enable the feature on
the pool).

Limited safety belt is provided for mounted root filesystem but use
caution when using a larger value.

Illumos issue:
5027 zfs large block support

MFC r272810: FV r272804:

Refactor the code and stop restore_object from creating two transactions.

Illumos issue:
3693 restore_object uses at least two transactions to restore an object

MFC r272809: MFV r272803:

Illumos issue:
5175 implement dmu_read_uio_dbuf() to improve cached read performance

MFC r268464: MFV r268452:

Explicitly mark file removal transactions as "presumed to result
in a net free of space" so they will not fail with ENOSPC.

Illumos issue: 4950 files sometimes can't be removed from a full
filesystem

MFC r268123: MFV r268119:

4914 zfs on-disk bookmark structure should be named *_phys_t

MFC r268079: MFV r267566:

4390 i/o errors when deleting filesystem/zvol can lead to space map
corruption

MFC r268075: MFV r267565:

4757 ZFS embedded-data block pointers ("zero block compression")
4913 zfs release should not be subject to space checks

MFC r266771: MFV r266766:

Add a new zfs property, "redundant_metadata" which can have values "all" or
"most". The default will be "all", which is the current behavior. When set
to all, ZFS stores an extra copy of all metadata. If a single on-disk block
is corrupt, at worst a single block of user data (which is recordsize bytes
long) can be lost.

Setting to "most" will cause us to only store 1 copy of level-1 indirect
blocks of user data files. This can improve performance of random writes,
because less metadata has to be written. In practice, at worst about
100 blocks (of recordsize bytes each) of user data can be lost if a single
on-disk block is corrupt.

The exact behavior of which metadata blocks are stored redundantly may change
in future releases.

Illumos issue: 3835 zfs need not store 2 copies of all metadata

MFC r260150: MFV r259170:

4370 avoid transmitting holes during zfs send

4371 DMU code clean up

illumos/illumos-gate@43466aae47bfcd2ad9bf501faec8e75c08095e4f

NOTE: Make sure the boot code is updated if a zpool upgrade is
done on boot zpool.

MFC r258744-258746: zfs: add zfs_freebsd_putpages

MFC r258634: MFV r258376: 3964 L2ARC should always compress metadata buffers

MFC r258632,258704: MFV r255255: 4045 zfs write throttle & i/o scheduler
performance work

Sponsored by: HybridCluster [merge]

MFC r287702: 5987 zfs prefetch code needs work

Rewrite the ZFS prefetch code to detect only forward, sequential
streams.

The following kstats have been added:

kstat.zfs.misc.arcstats.sync_wait_for_async

How many sync reads have waited for async read
to complete. (less is better)

kstat.zfs.misc.arcstats.demand_hit_predictive_prefetch

How many demand read didn't have to wait for I/O
because of predictive prefetch. (more is better)

zfetch kstats have been similified to hits, misses, and max_streams,
with max_streams representing times when we were not able to create
new stream because we already have the maximum number of sequences
for a file.

The sysctl variable/loader tunable vfs.zfs.zfetch.block_cap have been
replaced by vfs.zfs.zfetch.max_distance, which controls maximum bytes
to prefetch per stream.

illumos/illumos-gate@cf6106c8a0d6598b045811f9650d66e07eb332af

Illumos ZFS issues:

5987 zfs prefetch code needs work
https://www.illumos.org/issues/5987

MFC r287103 (by avg): 5692 expose the number of hole blocks in a file

FreeBSD porting notes:
- only kernel-side changes are merged
- the new ioctl is not actually implemented yet
- thus, the goal is to synchronize DMU code

illumos/illumos-gate@2bcf0248e992f292c7b814458bcdce2f004925d6

https://www.illumos.org/issues/5692
we would like to expose the number of hole (sparse) blocks in a file.
this can be useful to for example if you want to fill in the holes with
some data; knowing the number of holes in advances allows you to report
progress on hole filling. We could use SEEK_HOLE to do that but it would
be O(n) where n is the number of holes present in the file.

Author: Max Grossman <max.grossman@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Boris Protopopov <bprotopopov@hotmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>

Fix r288549 build on stable.

For some reason this (odd) code builds on head, but not on stable.

MFC r286705: 5960 zfs recv should prefetch indirect blocks
5925 zfs receive -o origin=

Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Author: Paul Dagnelie <pcd@delphix.com>

While running 'zfs recv' we noticed that every 128th 8K block required a
read. We were seeing that restore_write() was calling dmu_tx_hold_write()
and the indirect block was not cached. We should prefetch upcoming indirect
blocks to avoid having to go to disk and blocking the restore_write().

Allow an incremental send stream to be received as a clone, even if the
stream does not mark it as a clone.

MFC r286686: 5269 zpool import slow

illumos/illumos-gate@12380e1e701fda28c9e9f32d01cafb54af279eb5

https://www.illumos.org/issues/5269
When importing a pool (at boot or with zpool import) with many
filesystem, the process can take minutes. It doesn't matter whether
the pool has been exported cleanly or uncleanly. The problem is that
each dataset has its own log chain. On import, all datasets have to be
checked if there are logs to replay. The idea is to speed up this
process by paralellizing it.

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Arne Jansen <jansen@webgods.de>

MFC r286575: 5056 ZFS deadlock on db_mtx and dn_holds

Reviewed by: Will Andrews <willa@spectralogic.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Justin Gibbs <justing@spectralogic.com>

illumos/illumos-gate@bc9014e6a81272073b9854d9f65dd59e18d18c35

MFC r286541: 5531 NULL pointer dereference in dsl_prop_get_ds()

Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Bayard Bell <buffer.g.overflow@gmail.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Justin T. Gibbs <justing@spectralogic.com>

illumos/illumos-gate@e57a022b8f718889ffa92adbde47a8f08abcdb25

MFC r275782: MFV r275551:

Remove "dbuf phys" db->db_data pointer aliases.

Use function accessors that cast db->db_data to the appropriate
"phys" type, removing the need for clients of the dmu buf user
API to keep properly typed pointer aliases to db->db_data in order
to conveniently access their data.

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_leaf.c:
In zap_leaf() and zap_leaf_byteswap, now that the pointer alias
field l_phys has been removed, use the db_data field in an on
stack dmu_buf_t to point to the leaf's phys data.

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c:
Remove the db_user_data_ptr_ptr field from dbuf and all logic
to maintain it.

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dnode.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dbuf.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c:
Modify the DMU buf user API to remove the ability to specify
a db_data aliasing pointer (db_user_data_ptr_ptr).

cddl/contrib/opensolaris/cmd/zdb/zdb.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_diff.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_traverse.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_tx.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_bookmark.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dataset.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deadlist.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_deleg.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_destroy.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_dir.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_pool.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_prop.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_scan.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_synctask.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dsl_userhold.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_history.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_leaf.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_ioctl.c:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_impl.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_leaf.h:
Create and use the new "phys data" accessor functions
dsl_dir_phys(), dsl_dataset_phys(), zap_m_phys(),
zap_f_phys(), and zap_leaf_phys().

sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dataset.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dsl_dir.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_impl.h:
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/zap_leaf.h:
Remove now unused "phys pointer" aliases to db->db_data
from clients of the DMU buf user API.

Illumos issue:
5314 Remove "dbuf phys" db->db_data pointer aliases in ZFS

MFC r274337,r274673,274681,r275515:

ZFS large block support. The default recordsize remains at 128KB.

A new tunable/sysctl variable, vfs.zfs.max_recordsize is added to
allow adjusting the permitted maximum record size, or
zfs_max_recordsize, with a default of 1MB. ZFS will not allow
setting recordsize greater than zfs_max_recordsize as a safety
belt, because larger recordsize means greater read and write
latency and more memory usage.

Please note that booting from datasets that have recordsize greater
than 128KB is not supported (but it's Okay to enable the feature on
the pool).

Limited safety belt is provided for mounted root filesystem but use
caution when using a larger value.

Illumos issue:
5027 zfs large block support

MFC r272810: FV r272804:

Refactor the code and stop restore_object from creating two transactions.

Illumos issue:
3693 restore_object uses at least two transactions to restore an object

MFC r272809: MFV r272803:

Illumos issue:
5175 implement dmu_read_uio_dbuf() to improve cached read performance

MFC r268464: MFV r268452:

Explicitly mark file removal transactions as "presumed to result
in a net free of space" so they will not fail with ENOSPC.

Illumos issue: 4950 files sometimes can't be removed from a full
filesystem

MFC r268123: MFV r268119:

4914 zfs on-disk bookmark structure should be named *_phys_t

MFC r268079: MFV r267566:

4390 i/o errors when deleting filesystem/zvol can lead to space map
corruption

MFC r268075: MFV r267565:

4757 ZFS embedded-data block pointers ("zero block compression")
4913 zfs release should not be subject to space checks

MFC r266771: MFV r266766:

Add a new zfs property, "redundant_metadata" which can have values "all" or
"most". The default will be "all", which is the current behavior. When set
to all, ZFS stores an extra copy of all metadata. If a single on-disk block
is corrupt, at worst a single block of user data (which is recordsize bytes
long) can be lost.

Setting to "most" will cause us to only store 1 copy of level-1 indirect
blocks of user data files. This can improve performance of random writes,
because less metadata has to be written. In practice, at worst about
100 blocks (of recordsize bytes each) of user data can be lost if a single
on-disk block is corrupt.

The exact behavior of which metadata blocks are stored redundantly may change
in future releases.

Illumos issue: 3835 zfs need not store 2 copies of all metadata

MFC r260150: MFV r259170:

4370 avoid transmitting holes during zfs send

4371 DMU code clean up

illumos/illumos-gate@43466aae47bfcd2ad9bf501faec8e75c08095e4f

NOTE: Make sure the boot code is updated if a zpool upgrade is
done on boot zpool.

MFC r258744-258746: zfs: add zfs_freebsd_putpages

MFC r258634: MFV r258376: 3964 L2ARC should always compress metadata buffers

MFC r258632,258704: MFV r255255: 4045 zfs write throttle & i/o scheduler
performance work

Sponsored by: HybridCluster [merge]