From mboxrd@z Thu Jan 1 00:00:00 1970 From: Douglas Gilbert Subject: Re: ide-scsi with ide-hd? Date: Fri, 06 Dec 2002 21:28:47 +1100 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <3DF07BDF.8070907@torque.net> References: <3DF06AD0.5070507@rzg.mpg.de> Reply-To: dougg@torque.net Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: List-Id: linux-scsi@vger.kernel.org To: Thomas Soddemann Cc: linux-scsi@vger.kernel.org Thomas Soddemann wrote: > Hi, > > does anybody know whether there is there a possibility to use ide-scsi > in connection with an IDE HD? No, "ide" disks use the ATA standards (reference: www.t13.org) while ide tapes, floppies and cdroms tend to use the ATA Packet Interface (ATAPI) which is essentially a SCSI command set over an ide transport. The command set used by cdwriters is MMC (reference: www.t10.org ). > If so, where can I get more information from? By looking at the source > of ide-scsi I get the impression, that only IDE devices work, which have > a kind of SCSI origin. SCSI standards (www.t10.org) are essentially split into two layers: - command sets (e.g. primary (SPC), block (SBC), multi-media? (MMC) ) - transports (e.g. parallel (SPI), fibre channel (FCP), ieee1394 (sbp) ) The definitions of some important transports (e.g. ATAPI and USB mass storage) are found at their respective sites (i.e. not on www.t10.org ). > The intention is to use IDE HDs via the ide-scsi driver in connection > with a special file system (GPFS), since it does not (at least not > officially) support IDE drives. The ide-scsi driver looks like it is going away in the 2.5 series **. Cdrecord controlled cd/dvd writers via the sg driver which used the ide-scsi driver to access ATAPI devices. The SG_IO ioctl inside the sg driver been ported to the block level so now cdrecord can control both ATAPI writers directly via their block devices (e.g. /dev/hdd) and "real" SCSI (or pseudos like USB and 1394) via their block devices (e.g. /dev/sdc0). Unfortunately none of this helps you with an ATA _disk_. > Single node harddisk performance is not > really an issue, since GPFS is a parallel filesystem, and it will be > used with GBit Ethernet, in our case. ** Are there ATAPI tape drives using the ide-scsi driver? Doug Gilbert