On Wed, Jan 02 2002, David Brownell wrote: > > > requirement for drivers is that the transfer buffers can be passed to > > > pci_map_single() calls by the Host Controller Drivers (HCDs). The > > > device drivers, and URBs, don't expose such mappings, they only > > > require that they can be created/destroyed. > > > > .. which is the requirement that you want to change to use pci_map_page > > or pci_map_sg > > OK, I think I'm clear on this much then: in 2.5, to support block drivers > over USB (usb-storage only, for now) there needs to be an addition to > the buffer addressing model in usbcore, as exposed by URBs. > > - Current "transfer_buffer" + "transfer_buffer_length" mode needs to > stay, since most drivers aren't block drivers.
Why? Surely USB block drivers are not the only ones that want to support highmem. > - Add some kind of "page + offset" addressing model. Yes > Discussion of details can be taken off LKML, it'd seem. Though I'm > curious when the scatterlist->address field will vanish, making these > changes a requirement. Is that a 2.5.2 thing? Maybe 2.5.3, dunno for sure. > Also, I noticed that include/asm-sparc/pci.h doesn't include the > standard pci_map_page() call ... what's up with that? That surely > causes portability problems. It probably isn't up to snuff yet. -- Jens Axboe _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
