7466a7a33f
Dmitry Bogdanov <d.bogdanov@yadro.com> says: SAM-5 4.6.5.2 (Relative Port Identifier attribute) defines the attribute as unique across SCSI target ports: The Relative Port Identifier attribute identifies a SCSI target port or a SCSI initiator port relative to other SCSI ports in a SCSI target device and any SCSI initiator devices contained within that SCSI target device. A SCSI target device may assign relative port identifiers to its SCSI target ports and any SCSI initiator ports. If relative port identifiers are assigned, the SCSI target device shall assign each of its SCSI target ports and any SCSI initiator ports a unique relative port identifier from 1 to 65 535. SCSI target ports and SCSI initiator ports share the same number space. In the current TCM implementation, auto-incremented lun_rtpi weakly follows the model outlined by SAM-5 and SPC-4. In case of multiple SCSI target ports (se_portal_groups), which is common to scenario with multiple HBAs or multiple iSCSI/FC targets, it's possible to have two backstores (se_devices) with different values of lun_rtpi on the same SCSI target port. Similar issue happens during re-export. If a LUN of a backstore is removed from a target port and added again to the same target port, RTPI is incremented again and will be different from the first time. The two issues happen because each se_device increments RTPI for its own LUNs independently. The behaviour means that a SCSI application client can't reliably make any sense of RTPI values reported by a LUN as it's not really related to SCSI target ports. A conforming target implementation must ensure that RTPI field is unique per port. The patchset resolves the issue. Make RTPI be part of se_tpg instead of se_lun. Make it configurable. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.