On Sun, Feb 13, 2005 at 03:25:24PM +0100, Christoph Hellwig wrote: > On Sun, Feb 13, 2005 at 10:37:12AM +0200, Dan Bar Dov wrote: > > > I don't know who "we" here is, but we as the kernel developer > > > community certainly disagree. > > > > So how do you describe scsi mid layer? > > Scsi mid layer is exaclty a unifying API that hides the specific hardware > > device drivers from the upper layer abstractions. > > The kdapl model is identical to the scsi model - a single in-kernel API > > that hides different hardware specific implementations of RDMA. > > It's not really analogue. In SCSI the hardware (or at least the drivers) > all speak the same protocol (in a few different revisions), and the scsi > midlayer and upper level drivers implement most of that protocol. The > LLDDs program the different hardware implementing this protocol. > > See the SAM-2 or SAM-3 documents for details.
The right analogy for kDAPL in scsi land would be the CAM standard from T10.org that tried to specifiy in-kernel interfaces for SCSI. While a few Operating Systems tried to model their stack afer CAM (Digital Unix, FreeBSD), it soon became clear that the standard isn't implementable 1:1 in a real life system, was a hidrance in implementing clean and lean driver and had no chance following the development of new SAM substandards. _______________________________________________ openib-general mailing list [email protected] http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
