On Sat, 30 Oct 2004, Oliver Neukum wrote: > Am Samstag, 30. Oktober 2004 19:50 schrieb David Brownell: > > On Saturday 30 October 2004 09:50, Oliver Neukum wrote: > > > 2. No iommu is rare > > > > I thought they were all rare ... most x86 > > systems don't have them, for starters. > > (Though x86_64 has one.) > > True. > Maybe the typical users of sg and st are atypical. And the demise > of scsi scanners has diminished the user base of sg.
You missed the point -- the users of st and sg I was referring to are people using those drivers with USB-based devices. So the quality or quantity of SCSI adapter support is irrelevant to this discussion. (And remember that cdrecord uses the sg interface too!) To recap: If anyone is using st or sg with a USB device, it doesn't seem to bother them that not all USB controllers use DMA. The same is true for sd; scatter-gather I/O to disk sometimes is done from buffers in high memory. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
