Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r268075: MFV r267565:

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

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFV r245512:

* Illumos zfs issue #3035 [1] LZ4 compression support in ZFS.

LZ4 is a new high-speed BSD-licensed compression algorithm created
by Yann Collet that delivers very high compression and decompression
performance compared to lzjb (>50% faster on compression, >80% faster
on decompression and around 3x faster on compression of incompressible
data), while giving better compression ratio [1].

This version of LZ4 corresponds to upstream's [2] revision 85.

Please note that for obvious reasons this is not backward read
compatible. This means once a pool have LZ4 compressed data, these
data can no longer be read by older ZFS implementations.

Local changes:

- On-stack hash table disabled and using kernel slab allocator
instead, at this time. This requires larger kernel thread stack
for zio workers. This may change in the future should we adjusted
the zio workers' thread stack size.
- likely and unlikely will be undefined if they are already defined,
this is required for i386 XEN build.
- Removed De Bruijn sequence based __builtin_ctz family of builtins
in favor of the latter. Both GCC and clang supports these builtins.
- Changed the way the LZ4 code detects endianness.
- Manual pages modifications to mention the feature based on Illumos
counterpart.
- Boot loader changes to make it support LZ4 decompression.

[1] https://www.illumos.org/issues/3035
[2] http://code.google.com/p/lz4/source/list

Obtained from: Illumos (13921:9d721847e469)
Tested on: FreeBSD/amd64
MFC after: 1 month

- Correctly read gang header from raidz.
- Decompress assembled gang block data if compressed.
- Verify checksum of a gang header.
- Verify checksum of assembled gang block data.
- Verify checksum of uber block.

Submitted by: avg
MFC after: 3 days

Always pass data size for checksum verification function, as using
physical block size declared in bp may not always be what we want.
For example in case of gang block header physical block size declared
in bp is much larger than SPA_GANGBLOCKSIZE (512 bytes) and checksum
calculation failed. This bug could lead to accessing unallocated
memory and resets/failures during boot.

MFC after: 3 days

Initialize 'rc' properly before using it. This error could lead to infinite
loop when data reconstruction was needed.

MFC after: 3 days

Remove redundant size calculation.

MFC after: 3 days

zfs boot subroutines: correctly specify type of an integer literal

Found by adding more warning flags to zfs boot blocks build.

Approved by: re (kib)
MFC after: 1 week

Finally... Import the latest open-source ZFS version - (SPA) 28.

Few new things available from now on:

- Data deduplication.
- Triple parity RAIDZ (RAIDZ3).
- zfs diff.
- zpool split.
- Snapshot holds.
- zpool import -F. Allows to rewind corrupted pool to earlier
transaction group.
- Possibility to import pool in read-only mode.

MFC after: 1 month

Teach the (gpt)zfsboot and zfsloader raidz code to use its buffers
more efficiently.

Before this patch, in the worst case memory use would increase
exponentially on the number of drives in the raidz vdev.

Submitted by: Matt Reimer <mattjreimer@gmail.com>
Sponsored by: VPOP Technologies, Inc.
Silence from: dfr

Correct another case of not doing 64bit math. This allows mine and
other raidz2 volumes to boot.

Submitted by: Matt Reimer <mattjreimer@gmail.com>

Nobody spoke up, so assume my interpretation was correct and enable keyword
expansion for this file.

Unexpand $FreeBSD$.

Remove svn:keywords on a file that had fbsd:nokeywords (though I don't
understand the reason for the latter)

Expand $FreeBSD$

Add support for booting from raidz1 and raidz2 pools.

Some zfsboot fixes from Norikatsu Shigemura:

1. zfsboot2 (boot2) doesn't %d (printf), so change %d to %u.
2. chase new zpool versioning as SPA_VERSION.
Obtained from: sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h

Submitted by: nork

Update ZFS from version 6 to 13 and bring some FreeBSD-specific changes.

This bring huge amount of changes, I'll enumerate only user-visible changes:

- Delegated Administration

Allows regular users to perform ZFS operations, like file system
creation, snapshot creation, etc.

- L2ARC

Level 2 cache for ZFS - allows to use additional disks for cache.
Huge performance improvements mostly for random read of mostly
static content.

- slog

Allow to use additional disks for ZFS Intent Log to speed up
operations like fsync(2).

- vfs.zfs.super_owner

Allows regular users to perform privileged operations on files stored
on ZFS file systems owned by him. Very careful with this one.

- chflags(2)

Not all the flags are supported. This still needs work.

- ZFSBoot

Support to boot off of ZFS pool. Not finished, AFAIK.

Submitted by: dfr

- Snapshot properties

- New failure modes

Before if write requested failed, system paniced. Now one
can select from one of three failure modes:
- panic - panic on write error
- wait - wait for disk to reappear
- continue - serve read requests if possible, block write requests

- Refquota, refreservation properties

Just quota and reservation properties, but don't count space consumed
by children file systems, clones and snapshots.

- Sparse volumes

ZVOLs that don't reserve space in the pool.

- External attributes

Compatible with extattr(2).

- NFSv4-ACLs

Not sure about the status, might not be complete yet.

Submitted by: trasz

- Creation-time properties

- Regression tests for zpool(8) command.

Obtained from: OpenSolaris