On Sun, Jul 31, 2005 at 02:08:06PM +0300, Boris Zingerman wrote: > We have some driver that performs > zero-copy DMA to userspace allocated > buffers. The problem is that the device > cannot perform DMA to RAM pages > with physical addresses above 4G ( this > is heavily memory equipped computer) > My question is it somehow possible to > restrict memory mapping for shared > memory segments ( which are used > as DMA destination) to be physically > under 4G boundary ?
not from userspace; if, however, your userspace process does mmap(MAP_SHARED...) on a a character device file the driver exports, it can be done inside the driver. Cheers, Muli -- Muli Ben-Yehuda http://www.mulix.org | http://mulix.livejournal.com/ ================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
