diff --git a/scst/README b/scst/README index db22d5495..3b857b7dd 100644 --- a/scst/README +++ b/scst/README @@ -342,7 +342,7 @@ subdirectories "vdisk" and "vcdrom". They have similar layout: will go from the initiator. - BLOCKIO - enables block mode, which will perform direct block - IO with the device, bypassing page-cache for all operations. + IO with a block device, bypassing page-cache for all operations. This mode works ideally with high-end storage HBAs and for applications that either do not need caching between application and disk or need the large block throughput. See also below. diff --git a/www/scst_page.html b/www/scst_page.html index 8e519ebc3..1181dbef9 100644 --- a/www/scst_page.html +++ b/www/scst_page.html @@ -54,16 +54,20 @@ with different access permissions. For instance, initiator A could see exported from target T devices Da and Db read-writable, and initiator B from the same target T could see devices Db read-only and Dc read-writable.
- -
  • Complete SMP support.
  • Emulates necessary functionality of SCSI host adapter, because -from a remote initiator's point of view SCST acts as a SCSI host with +from remote initiators point of view SCST acts as a SCSI host with its -own devices. Some of the emulated functions are the following: +own devices. This is especially important in pass-through mode with one +to many relationship, i.e. when +multiple initiators can connect to the exported pass-through devices. +You can find more deep elaboration why it is needed in this +message in linux-scsi mailing list. Some of the emulated functions are +the following:

    Interoperability between SCST and local -SCSI initiators (like sd, st) is +SCSI initiators (i.e. sd, st, etc.) is the additional issue that SCST is going to address (it is not implemented yet). It is necessary, because local SCSI initiators can change the state of the device, for example RESERVE the device, or some -of its parameters and that would be done behind SCST, which could lead -to various problems. Thus, RESERVE/RELEASE commands, locally generated +of its parameters and that could be done behind SCST, which could lead +to various problems, including data corruption. Thus, RESERVE/RELEASE +commands, locally generated UNIT ATTENTIONs, etc. should be intercepted and processed as if local -SCSI initiators act as remote SCSI initiators connected to SCST. This -feature requires some the kernel modification. Since in the current -version it is not implemented, SCST and target drivers are -able to work with any version of Linux 2.6 kernel.
    +SCSI initiators act as remote SCSI initiators connected to SCST.

    Interface between SCST and target drivers is based on work, done by University @@ -111,26 +116,44 @@ of New Hampshire Interoperability Labs (UNH IOL) for the , which is currently developed on SourceForge.net.

    -

    The latest stable version is 0.9.5. It -supports SCSI disks (type 0), tapes (type 1), processors (type +

    SCST supports the following I/O modes:
    +

    + +

    The latest stable version is 0.9.5. +Requires Linux kernel 2.6.14 or higher. Tested mostly on i386 and x86_64, but should also work on any other supported by Linux platform. More detail information you could find in -the project's README file.
    +the project's README file.

    Starting from version 0.9.4 2.4 Linux -kernels are not supported anymore, although there could be new SCST -releases for those kernels with very important bug fixes. The latest +kernels are not supported anymore. The latest stable -version of SCST with 2.4 kernels support is 0.9.3.1-24. +version of SCST for 2.4 kernels is 0.9.3.1-24.

    If you have any questions you can ask them on the SCST SF.net page either using forum, or scst-devel mailing list.
    @@ -140,7 +163,8 @@ list.
    page
    Change Log
    Documentation: HTML, PDF
    + href="doc/scst_pg.pdf">PDF, scst_user +interface description
    Some nice SCST call graphs, created by Ming Zhang: init_scst, scst_cmd_thread, web-based SVN repository viewer or using anonymous access: