Fix build.
MFV r273617: netcat from OpenBSD 5.6.

MFC after:	2 weeks
- Print out "Bail out!" in die(..) so prove terminates immediately
- Handle the output from newer versions of openssl md5, similar to what
  pjd@ did in r248304

MFC after: 2 weeks
Sponsored by: EMC / Isilon Storage Division
Move the redirection to stderr out of the cmd variable assignment

Putting 2>/dev/null in cmd= escapes the redirection operation, which causes
mdconfig to think it's a filename

MFC after: 2 weeks
X-MFC with: r273627
Sponsored by: EMC / Isilon Storage Division
rlimit: plug duplicate assertion

counter sanity is already checked by refcount_release.
Bail out of the script on FreeBSD due to deterministic panic issue

PR: 191573
Sponsored by: EMC / Isilon Storage Division
Bail out of the script on FreeBSD due to deterministic panic issue

PR: 194586
Sponsored by: EMC / Isilon Storage Division
Bail out of the script on FreeBSD due to deterministic panic issue

PR: 194587
Sponsored by: EMC / Isilon Storage Division
Bail out of the script on FreeBSD due to deterministic panic issue

PR: 194589
Sponsored by: EMC / Isilon Storage Division
Fix a use of an uninitialized variable by makeing sure
that sctp_med_chunk_output() always initialized the reason_code
instead of relying on the caller.
The variable is only used for debugging purpose.
This issue was reported by Peter Bostroem from Google.

MFC after: 3 days
Add basic iSNS client to the iSCSI target.

This makes ctld(8) register its iSCSI targets and portals on configured
iSNS servers to allow initiators find them without active discovery.

Fetching of allowed initiators from iSNS is not implemented now, so target
ACLs still should be configured manually.

Reviewed by:	trasz@
MFC after:	1 month
Sponsored by:	iXsystems, Inc.
Revert somewhat hackish geom_disk optimization, committed as part of r256880,
and the following r273143 commit, supposed to workaround introduced issue by
quite innocent-looking change.

While there is no clear understanding why, but r273143 is accused in data
corruption in some environments with high I/O load.  I personally don't see
any problem in that commit, and possibly it is just a trigger to some other
bug somewhere, but better safe then sorry for now.

Requested by:	scottl@
MFC after:	3 days
Add support for 12/16-byte EUI and 16-byte NAA IDs.

MFC after:	1 week
This change addresses 4 bugs in ZFS exposed by Richard Kojedzinszky's
crash.sh script attached to FreeNAS bug 4109:
https://bugs.freenas.org/issues/4109

Three are in the snapshot layer:
a) AVG explains in his notes: https://wiki.freebsd.org/AvgVfsSolarisVsFreeBSD

"VOP_INACTIVE must not do any destructive actions to a vnode
and its filesystem node, nor invalidate them in any way."
gfs_vop_inactive and zfsctl_snapshot_inactive did just that. In
OpenSolaris VOP_INACTIVE is much closer to FreeBSD's VOP_RECLAIM.
Rename & move them to gfs_vop_reclaim and zfsctl_snapshot_reclaim
and merge in the requisite vnode_destroy from zfsctl_common_reclaim.

b) gfs_lookup_dot and various zfsctl functions do not honor the
FreeBSD VFS convention of only locking from the root downward. When
looking up ".." the convention is to drop the current leaf vnode lock before
acquiring the directory vnode and then subsequently re-acquiring the lock on the
leaf vnode. This fixes that in all the places that our exercised by crash.sh.

c) The snapshot may already be unmounted when the directory vnode is reclaimed.
Check for this case and return.

One in the common layer:
d) Callers of traverse expect the reference to the vnode passed in to be
maintained. Don't release it.

This last one may be an unclear contract. There may in fact be some callers that
do expect the reference to be dropped on success in addition to callers that
expect it to be released. In this case a further audit of the callers is needed
and a consensus on the correct behavior.

PR:	184677
Submitted by:	kmacy
Reviewed by:	delphij, will, avg
MFC after:	2 weeks
Sponsored by:	iXsystems
Clarify that pthread_cleanup_push()/pop() are implemented as macros that
create a new code block and thus must be balanced at the same lexical
scope.  (This is also a requirement in POSIX.)

PR:		194280
Submitted by:	dr2867.business@pacbell.net
MFC after:	1 week
Use correct type in __DEVOLATILE().
Set the caching mode for the usermode mapping of the HPET registers
page to uncached.

Reviewed by:	rpaulo
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Fix a few issues with creating VOLUME_LABEL for the
installation ISOs:

 - TYPE, BRANCH, and REVISION are only defined if
   OSRELEASE is not defined, so in situations where
   one might set OSRELEASE for an in-house ISO build,
   VOLUME_LABEL would be empty.

 - makefs(8) limits the volume label to 32 characters,
   which for the powerpc64 case, OSRELEASE expands to
   FreeBSD-11.0-CURRENT-powerpc-powerpc64.  Even with
   removing the prefixing 'FreeBSD-', the string is 30
   characters long, leaving zero room for suffixing the
   type of ISO media (BO for bootonly, CD for cdrom, and
   DVD for dvdrom).

Resolve these by defining VOLUME_LABEL when defining
OSRELEASE if unset.  If OSRELEASE is defined by the
builder, use the OSRELEASE from that definition as the
VOLUME_LABEL.

In addition, for cases where both TARGET and TARGET_ARCH
are used for the VOLUME_LABEL, use TARGET_ARCH if it
differs from TARGET.

There are probably a few sharp edges here yet, but these
problems are going to affect the powerpc/powerpc64 builds
for 10.1-RELEASE, so the immediate concern is fixing the
underlying problem at hand quickly, and less so about the
elegance of the fix.

MFC after:	3 days
X-MFC-10.1:	yes, asap
Sponsored by:	The FreeBSD Foundation
Now that sysctl_root is only called with sysctl lock in shared mode, update
its assertion to require that.

Update comment missed in r273400: sysctl_xlock/unlock -> sysctl_xlock/xunlock

Noted by: jhb
Don't pass the 'error' return from an I/O port handler directly to vm_run().

Most I/O port handlers return -1 to signal an error. If this value is returned
without modification to vm_run() then it leads to incorrect behavior because
'-1' is interpreted as ERESTART at the system call level.

Fix this by always returning EIO to signal an error from an I/O port handler.

MFC after:	1 week