From: "Alan Cox" <alan@lxorguk.ukuu.org.uk>
> > For framebuffers addresses, there is no page structure, and then the
> > page reference count updates read/write to random memory.
>
> If it is a physical pci bus object why do we need to refcount it,
> surely "no page" is ok. Its just up to the driver not to do anything
> stupid and the core code to honour the pci/pci transfer quirks (or
> when faced with a hard one just say "no")
>
With multi-threaded apps, munmap() during O_DIRECT is possible. vma
structures don't contain a reference count.
For ptrace, taking the physical address from the PTE and ioremapping it
temporarily would work, but ...
--
Manfred
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This archive was generated by hypermail 2b29 : Thu Jan 31 2002 - 21:00:54 EST