************************* Notes for general release ******************** The new scsi drivers are now available for alpha testing. There are a number of new features, and I ask that you read this completely before you proceed. New Features in high level scsi code: * Multiple outstanding requests per host. There is currently a limit of one request per lun, but this could be expanded, if needed. * Scatter-gather now supported. For host adapters that can deal with this, there is a *very* significant performance increase. * All of "while(condition)" waits have been turned into sleeps. * The scsi disk driver digs down into the request list and looks for queueable commands. This will improve performance on systems with multiple disk drives. * Commands are passed mainly by structure pointer. This nearly eliminates the possibility of information crosstalk between two different requests. * >16Mb memory configurations work with DMA, and will work with scatter-gather code. * Support is present for host adapters that can make good use of multiple commands to the same lun. I guess what I had in mind was the scsi concept of command linking. Drew says that he can make good use of this in the ST0x drivers. * Support for lun!= 0 is now present, and should work. * The constants MAX_SD, MAX_SR, MAX_ST have been eliminated. The scsi code dynamically allocates all of the required structures at boot time, based upon the actual number of devices detected as the host adapters are scanned. The constant MAX_SCSI_DEVICES has also been eliminated. There are no builtin limits as to how many scsi devices you can have, but there is a practical limit of 7 device ids per scsi bus (the host adapter itself counts for one), and there are up to 8 different luns at each device id. Low level changes: * All host adapters changed to use new parameter passing. * Adaptec driver now supports multiple requests and scatter-gather. Board can now be set at either 0x330 or 0x334, and the driver will query the board to determine the IRQ number and DMA channel. BIOS on the Adaptec no longer needs to be enabled. * Drew is working on updating the ST0x support. * Rick Faith has offered to work on the Future Domain, but will not be able to start on it for a while, because of school. * Dave Gentzel has offered to update the Ultrastor driver. * Thomas Wuensche, has offered to update the 7000fasst driver. As of now, only the Adaptec driver has been modified to work with the new code and take advantage of all of the features. As other drivers are modified the patches will be installed, and I will make note of the fact.