OpenZFS issue-7252 compressed zfs send / receive

[don-brady]

Pick up remaining changes for 7252 since original integration into zfsonlinx.

Authored by: Dan Kimmel [email protected]
Ported-by: Don Brady [email protected]

OpenZFS-issue: https://www.illumos.org/issues/7252
OpenZFS-commit: openzfs/openzfs@5602294f

Porting Notes: most of 7252 was already picked up during ABD work.
This commit represents the gap from the final commit to openzfs.

Motivation and Context

We want to match upstream OpenZFS for compressed zfs send / receive.
The first commit here represents the kernel module changes.
The zfs test suite changes will follow in another commit.

How Has This Been Tested?

ztest and basic pool functionality

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the ZFS on Linux code style requirements.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• All commit messages are properly formatted and contain Signed-off-by.
• Change has been approved by a ZFS on Linux member.

[mention-bot]

@don-brady, thanks for your PR! By analyzing the history of the files in this pull request, we identified @behlendorf, @grwilson and @ahrens to be potential reviewers.

[DeHackEd]

Change the commit message (first line) to: OpenZFS 7252 - compressed... to resolve the style check errors.

Also interested to see that the OpenZFS style variable declaration style is now allowed.

[behlendorf]

You can ignore the zpool_labelclear_active failure, that test case failure was accidentally introduced to master in commit dbb38f6 and should get resolved soon.

[behlendorf]

Replaced by #6067 which includes this PR and all the test cases from #5951. Please review!