Messages in this thread |  | | | Date | Tue, 21 Jul 1998 17:54:11 +0200 | | Subject | Re: [PATCH] New phys_addr() syscall | | From | Inaky Perez Gonzalez <> |
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>>>>> "Alan" == Alan Cox <alan@lxorguk.ukuu.org.uk> writes:
>> I was thinking of allowing the USB Stack to directly write to user >> pages using PCI. If PCI doesn't also honour the bits we need, could >> it be done by hand as the write is finished?
Alan> Ok firstly why do you need to write directly to user space
It is to offer a posibility to waste less resources. If I've got this USB disk drive and I order to write 100K, if I know where they are at use space, I just have to write from user space directly to the drive. This way there is no intermediate buffering ... well, the disk drive was a bad example [disk cache]; let's change it for Audio device.
Alan> - you would normally want to buffer messages up anyway surely,
The message-type transfer are no problem, they're better using buffers, as they are small. I'm more concerned on _long_ transfers. Alas, it is not too difficult to do on the USB code [if I'm not doing it wrong :)].
Cheers
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