On Thu, 2002-05-30 at 13:14, Tom Tang wrote: > Hello, > > 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...
An associated question: while I was looking at the DRM's mmap for the shared memory area, I think I figured out that you didn't need memory that was going to be mmapped to be physically contiguous (since the device pager would get each page of it separately). Was I right? -- Eric Anholt <[EMAIL PROTECTED]> http://gladstone.uoregon.edu/~eanholt/dri/ To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
