From owner-freebsd-scsi Tue Apr 9 8:48:55 2002 Delivered-To: freebsd-scsi@freebsd.org Received: from bosvwl02.infy.com (bosvwl02.infy.com [216.52.49.36]) by hub.freebsd.org (Postfix) with SMTP id 0F22A37B400 for ; Tue, 9 Apr 2002 08:48:50 -0700 (PDT) Received: from 192.168.200.81 by bosvwl02.infy.com (InterScan E-Mail VirusWall NT); Tue, 09 Apr 2002 11:48:03 -0400 Received: from BLRKECIMR01.ad.infosys.com ([192.168.200.58]) by indhubbhs01.ad.infosys.com with Microsoft SMTPSVC(5.0.2195.4905); Tue, 9 Apr 2002 21:18:00 +0530 Received: from kecmsg02.ad.infosys.com ([192.168.18.90]) by BLRKECIMR01.ad.infosys.com with Microsoft SMTPSVC(5.0.2195.4905); Tue, 9 Apr 2002 21:18:00 +0530 X-MimeOLE: Produced By Microsoft Exchange V6.0.5762.3 content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Subject: RE: SCSI Callback function not getting called Date: Tue, 9 Apr 2002 21:08:16 +0530 Message-ID: <755FA95DB839D211856B0008C7287D930F3286E8@kecmsg02.ad.infosys.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: SCSI Callback function not getting called Thread-Index: AcHbnXu6qwUvAHSaTo2vsyBcKBRJlwEPr+hg From: "Yassar S" To: "Kenneth D. Merry" Cc: X-OriginalArrivalTime: 09 Apr 2002 15:48:00.0500 (UTC) FILETIME=[ED4B8340:01C1DFDD] Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org I'm currently developing an application on FreeBSD3.1 to test the SCSI devices (hard disks). Whenever I do read/write on the SCSI disks, I'm not able read or write more than 126 blocks in a single operation. Any pointers what could be the reason? How can I ovecome this limitation? Thanks Yassar. -----Original Message----- From: Kenneth D. Merry [mailto:ken@kdm.org] Sent: Thursday, April 04, 2002 11:19 AM To: Yassar S Cc: freebsd-scsi@FreeBSD.ORG Subject: Re: SCSI Callback function not getting called On Thu, Apr 04, 2002 at 09:15:25 +0530, Yassar S wrote: > I'm not writing a driver. I'm writing an application which uses > the SIM calls like scsi_read_write etc. Those aren't SIM calls. The SIM layer (SIM =3D=3D System Interface Module) is the layer where = the various SCSI and FC drivers live. Functions like scsi_read_write() fill CCBs, they don't actually execute = any I/O. You probably want to look at the cam(3) man page, and in particular = you'll want to look at the camcontrol(8) source, located in = src/sbin/camcontrol. That's probably the best example of how to issue SCSI commands from userland. The short answer to your original question is: scsi_read_write() and = the other commands like it just fill CCBs, they don't actually execute I/O. = In addition, the callback function pointer is only used in the kernel, not = in userland. In userland, CCBs are currently issued synchronously, so = there is no need for a callback function anyway. Ken --=20 Kenneth Merry ken@kdm.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message