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 r270279:

Make the iSCSI stack use __FBSDID() properly.

Sponsored by: The FreeBSD Foundation

MFC r268795:
Fix ctld crash on startup if target alias is not set.

MFC r268328:
Close race in r268291 between port destruction, delayed by sessions
teardown, and new port creation during `service ctld restart`.

Close it by returning iSCSI port internal state, that allows to identify
dying ports, which should not be counted as existing, from really alive.

MFC r268302:
Pass through iSCSI session ISID from LOGIN request to the CTL frontend.

ISID is an important part of initiator transport ID for iSCSI. It is not
used now, but should be to properly implement persistent reservation.

MFC r268293:
Burry devid port method, which was a gross hack.

Instead make ports provide wanted port and target IDs, and LUNs provide
wanted LUN IDs. After that core Device ID VPD code only had to link all
of them together and add relative port and port group numbers.

LUN ID for iSCSI LUNs no longer created by CTL, but by ctld, and passed
to CTL as "scsiname" LUN option. This makes LUNs to report the same set
of IDs, independently from the port through which it is accessed, as
required by SCSI specifications.

MFC r268291:
Create separate CTL port for every iSCSI target (and maybe portal group).

Having single port for all iSCSI connections makes problematic implementing
some more advanced SCSI functionality in CTL, that require proper ports
enumeration and identification.

This change extends CTL iSCSI API, making ctld daemon to control list of
iSCSI ports in CTL. When new target is defined in config fine, ctld will
create respective port in CTL. When target is removed -- port will be
also removed after all active commands through that port properly aborted.
This change require ctld to be rebuilt to match the kernel.

As a minor side effect, this allows to have iSCSI targets without LUNs.
While that may look odd and not very useful, that is not incorrect.

MFC r267648:
serial_num and device_id fields are not necessarily null-terminated.

Before this it was impossible to use all 16 bytes of serial number, and
client always got serial number NULL-terminated, that is not required.

MFC r264530:

Properly pass the initiator address when running in proxy mode.

Sponsored by: The FreeBSD Foundation

MFC r264526:

Properly identify target portal when running in proxy mode. While here,
remove CTL_ISCSI_CLOSE, it wasn't used or implemented anyway.

Sponsored by: The FreeBSD Foundation

MFC r264524:

Make it possible for the iSCSI target side to operate in both normal
and ICL_KERNEL_PROXY mode, and fix some bit rot so the latter actually
works again.

Sponsored by: The FreeBSD Foundation

MFC r261757:

Rename a variable, no functional changes.

Sponsored by: The FreeBSD Foundation

MFC r261765:

Improve error reporting.

Sponsored by: The FreeBSD Foundation

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

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

Fix off-by-one.

Coverity CID: 1011375
Approved by: re (glebius)
Sponsored by: FreeBSD Foundation

Fix several problems in the new iSCSI stack; this includes interoperability
fix for LIO (Linux target), removing possibility for the target to avoid mutual
CHAP by choosing to skip authentication altogether, and fixing truncated error
messages in iscsictl(8) output. This also fixes several of the problems found
with Coverity.

Note that this change requires world rebuild.

Coverity CID: 1088038, 1087998, 1087990, 1088004, 1088044, 1088041, 1088040
Approved by: re (blanket)
Sponsored by: FreeBSD Foundation

Make iscsictl(8) automatically try to load the iscsi module. While here,
improve module loading in iscsid(8) and ctld(8).

Approved by: re (delphij)

Bring in the new iSCSI target and initiator.

Reviewed by: ken (parts)
Approved by: re (delphij)
Sponsored by: FreeBSD Foundation