On Thu, 30 May 2002, Tom Tang wrote: > I have a question about implementing mmap functions in > device drivers. Thinking it would be simple, I contigmalloc'd > a buffer of PAGE_SIZE and returned it using atop like other > mmap device implementations. However when my userland program > mmaps the device with offset 0, when I try accessing the returned > pointer, it returns me invalid memory address. Any help would > be appreciated...
Generally, after the machine is started, memory gets too fragmented to use contigmalloc. If you preload the module and do the contigmalloc at attach time it should succeed. Doug White | FreeBSD: The Power to Serve [EMAIL PROTECTED] | www.FreeBSD.org To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message