Add virtio bus 'poll' method allowing us to inform backend we are
going to poll virtqueue.

Use on BERI soft-core to invalidate cpu caches.

Reviewed by:	bryanv
Sponsored by:	DARPA, AFRL
Increase the buffer size to keep the list of programm names when
parsing programm specification. It is safe to not check out of bounds
access, because !isprint(p[i]) check will stop reading, when '\0'
character will be read from the input string.

Obtained from:	Yandex LLC
MFC after:	1 week
Sponsored by:	Yandex LLC
Provide a dead version of if_get_counter.

Submitted by:	glebius
Reported by:	np
Fix typo in comments.

Noticed by: brooks@
Add some new modes to OpenCrypto.  These modes are AES-ICM (can be used
for counter mode), and AES-GCM.  Both of these modes have been added to
the aesni module.

Included is a set of tests to validate that the software and aesni
module calculate the correct values.  These use the NIST KAT test
vectors.  To run the test, you will need to install a soon to be
committed port, nist-kat that will install the vectors.  Using a port
is necessary as the test vectors are around 25MB.

All the man pages were updated.  I have added a new man page, crypto.7,
which includes a description of how to use each mode.  All the new modes
and some other AES modes are present.  It would be good for someone
else to go through and document the other modes.

A new ioctl was added to support AEAD modes which AES-GCM is one of them.
Without this ioctl, it is not possible to test AEAD modes from userland.

Add a timing safe bcmp for use to compare MACs.  Previously we were using
bcmp which could leak timing info and result in the ability to forge
messages.

Add a minor optimization to the aesni module so that single segment
mbufs don't get copied and instead are updated in place.  The aesni
module needs to be updated to support blocked IO so segmented mbufs
don't have to be copied.

We require that the IV be specified for all calls for both GCM and ICM.
This is to ensure proper use of these functions.

Obtained from:	p4: //depot/projects/opencrypto
Relnotes:	yes
Sponsored by:	FreeBSD Foundation
Sponsored by:	NetGate
Move KTR_CXGBE from t4_tom.h to adapter.h so that the base if_cxgbe
code can use it too.

MFC after:	1 week
MFV r275542:

If a dnode has a spill block and there is an error while accessing
a data block then traverse_dnode() loses information about that error
and returns a status of visiting the spill block.

This issue is discovered by Spectra Logic.

Illumos issue:
    5311 traverse_dnode may report success when it should not

Original author:	gibbs
MFC after:		2 weeks
MFV r275543:

Remove always true tests for ds->ds_phys' presence.

Clean up assertions in dsl_dataset_disown.

Remove unreachable code in dsl_dataset_disown().

Illumos issue:
    5310 Remove always true tests for non-NULL ds->ds_phys

MFC after:	2 weeks
MFV r275544:

Clean up some duplicated code in dnode_sync() around freeing spill blocks.

Illumos issue:
    5350 clean up code in dnode_sync()

MFC after:	2 weeks
MFV r275545:

If zio_checksum_error() returns other than ECKSUM (e.g. EINVAL), it does not
fill in the "zio_bad_cksum_t *info" parameter. Caller should not attempt to
use it in this case.

Illumos issue:
    5348 zio_checksum_error() only fills in info if ECKSUM

MFC after:	2 weeks
MFV r275546:

Reduce scrub activities when system there is enough dirty data, namely when
dirty data is more than zfs_vdev_async_write_active_min_dirty_percent (once
we start to increase the number of concurrent async writes).

While there also correct rounding error which would make scrub end up
pausing for (zfs_txg_timeout + 1) seconds instead of the desired
zfs_txg_timeout seconds.

Illumos issue:
    5351 scrub goes for an extra second each txg
    5352 scrub should pause when there is some dirty data

MFC after:	2 weeks
MFV r275547:

Port Illumos 'zfs allow' examples update.  While I'm there also fix
a typo.

Illumos issue:
    4181 zfs(1m): 'zfs allow' examples in the man page are outdated

MFC after:	2 weeks
MFV r275548:

Verify that the block pointer is structurally valid, before attempting to
read it in.  It can only be invalid in the case of a ZFS bug, but this
change will help identify such bugs in a more transparent way, by
panic'ing with a relevant message, rather than indexing off the end of an
array or something.

Illumos issue:
    5349 verify that block pointer is plausible before reading

MFC after:	2 weeks
The vinactive() call in vgonel() may start writes for the dirty pages,
creating delayed write buffers belonging to the reclaimed vnode.  Put
the buffer cleanup code after inactivation.

Add asserts that ensure that buffer queues are empty and add BO_DEAD
flag for bufobj to check that no buffers are added after the cleanup.
BO_DEAD is only used by INVARIANTS-enabled kernels.

Reported and tested by:	pho (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Only sleep interruptible while waiting for suspension end when
filesystem specified VFCF_SBDRY flag, i.e. for NFS.

There are two issues with the sleeps.  First, applications may get
unexpected EINTR from the disk i/o syscalls.  Second, interruptible
sleep allows the stop of the process, and since mount point is
referenced while thread sleeps, unmount cannot free mount point
structure' memory, blocking unmount indefinitely.

Even for NFS, it is probably only reasonable to enable PCATCH for intr
mounts, but this information is currently not available at VFS level.

Reported and tested by:	pho (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Add facility to stop all userspace processes.  The supposed use of the
feature is to quisce the system before suspend.

Stop is implemented by reusing the thread_single(9) with the special
mode SINGLE_ALLPROC.  SINGLE_ALLPROC differs from the existing
single-threading modes by allowing (requiring) caller to operate on
other process.  Interruptible sleeps for !TDF_SBDRY threads are
suspended like SIGSTOP does it, instead of aborting the sleep, like
SINGLE_NO_EXIT, to avoid spurious EINTRs on resume.

Provide debugging sysctl debug.stop_all_proc, which causes total stop
and suspends syncer, while waiting for variable reset for resume.  It
is used for debugging; should be removed after the real use of the
interface is added.

In collaboration with:	pho
Discussed with:	avg
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Fix markup.

MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Update llvm patches for r274286 and r275633 so all the tests will pass.
MFV r247174:

Expose arc_meta_limit, et al via kstats.

Note that as a result, vfs.zfs.arc_meta_used is removed.
The existing vfs.zfs.arc_meta_limit sysctl/tunable is retained
with a SYSCTL_PROC wrapper.

Illumos ZFS issues:
    3561 arc_meta_limit should be exposed via kstats

Relnotes:	yes
MFC after:	2 weeks
Add _NEW flag to mtx(9), sx(9), rmlock(9) and rwlock(9).
A _NEW flag passed to _init_flags() to avoid check for double-init.

Differential Revision:	https://reviews.freebsd.org/D1208
Reviewed by:	jhb, wblock
MFC after:	1 Month