On 09/30/05 12:26, Andrew Patterson wrote: > > I talked to one of the authors of these specs. SDI is an attempt to > create an open standard for the somewhat proprietary CSMI spec developed > by HP. It is currently languishing in t10 due to the IOCTL problem you > describe below (the "no new IOCTL's" doctrine caught them by surprise). > There is some thought to going to a write()/read() on a character device > model, but this has various problems as well. I think that read/write from a char device is going away too. For this reason I showed the whole picture of the SAS domain in sysfs _and_ created a binary file attr to send/receive SMP requests/responses to control the domain and get attributes ("smp_portal" binary attr of each expander). It is completely user space driven and a user space library is simple to write. See drivers/scsi/sas/expander_conf.c which is a user space utility. For the output see Announcement 3: http://linux.adaptec.com/sas/Announce_2.txt or here: http://marc.theaimsgroup.com/?l=linux-scsi&m=112629509318354&w=2 The code which implements it is very tiny, at the bottom of drivers/scsi/sas/sas_expander.c >>Sorry, did I mention "ioctl", >>oh that makes SDI unacceptable. Almost a year ago that is what >>happened to the first proposed SAS driver for Linux. > > > That was one of the reasons the MPT Fusion and Adaptec drivers were > rejected. There were others as well, such as lack of a SAS transport > class. You mean the first Adaptec SAS "adp94xx" driver. BTW, neither the original "adp94xx", nor the subsequent "aic94xx" Adaptec drivers implmented _any_ ioctls for CSMI/SDI. Luben - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html