Frame buffer / mmap() weirdness

Momchil Velikov velco at fadata.bg
Thu Dec 2 02:06:01 EST 1999


Gabriel Paubert wrote:
> 
> On Wed, 1 Dec 1999, Momchil Velikov wrote:
> >   [a & ~PAGE_MASK, (a + off + PAGE_SIZE - 1) & ~PAGE_SIZE)
> > to
> >   [b & ~PAGE_MASK, (b + off + PAGE_SIZE - 1) & ~PAGE_SIZE)
> 
> Some PAGE_SIZE are actually PAGE_MASK in this snippet...

Oops, my PAGE fault. It should be
  [a & PAGE_MASK, (a + off + ~PAGE_MASK) & PAGE_MASK )
to
  [b & PAGE_MASK, (b + off + ~PAGE_MASK) & PAGE_MASK )

where PAGE_MASK == ~(PAGE_SIZE -1).

Regards,
-velco

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