It allows to push out some final data from the send queue to the socket
before its close. In particular, it increases chances for logout response
to be delivered to the initiator.
Before this change target could send R2T request for write transfer of any
size, that could violate iSCSI RFC, which allows initiator to limit maximum
R2T size by negotiating MaxBurstLength connection parameter.
Also report an error in case of write underflow, when initiator provides
less data than initiator expects. Previously in such case our target
sent R2T request for non-existing data, violating the RFC, and confusing
some initiators. SCSI specs don't explicitly define how write underflows
should be handled and there are different oppinions, but reporting error
is hopefully better then violating iSCSI RFC with unpredictable results.
MFC after: 2 weeks
or I_T NEXUS LOSS, clear all minor UAs for the LUN, redundant in this case.
All SAM specifications tell that target MAY do it, but libiscsi initiator
seems require it to be done, terminating connection with error if some more
UAs happen to be reported during iSCSI connection.
MFC after: 3 days
Using pointer from the cdev directly is dangerous since we have no reference
on it, and it may change any time. That caused panic if device has gone.
While there, report capacity change only if it really changed.
MFC after: 3 days
Without clustering support we any way have only one group of permanently
active ports, but that gives us one more supported VMWare feature. ;)
Solaris' Comstar also reports it even when only one port is present.
It allows to bypass range checks between UNMAP and READ/WRITE commands,
which may introduce additional delays while waiting for UNMAP parameters.
READ and WRITE commands are always processed in safe order since their
range checks are almost free.
Before this change UNMAP completely blocked other I/Os while running.
Now it blocks only colliding ones, slowing down others only due to ZFS
locks collisions.
Sponsored by: iXsystems, Inc.
kern.cam.ctl.iscsi.ping_timeout to 0. This fixes interoperability with
some initiators that don't properly support NOP-Ins, namely iPXE/gPXE.
Submitted by: Chen Wen <pokkys@gmail.com>
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
At this moment it works only for files and ZVOLs in device mode since BIOs
have no respective respective cache control flags (DPO/FUA).
MFC after: 1 month
Sponsored by: iXsystems, Inc.
sizeof(struct scsi_inquiry_data) of 256 bytes combined with off-by-one
error in the changed code gave total INQUIRY data length above 255 bytes,
that was maximal INQUIRY length in SPC-2. While SPC-3 increased the
maximal length to 64K, at least sg3_utils are still confused by that.
MFC after: 1 week
This allows to avoid extra network traffic when copying files on NTFS iSCSI
disks within one storage host by drag'n'dropping them in Windows Explorer
of Windows 8/2012. It should also accelerate Hyper-V VM operations, etc.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
