Re: [patch] vmalloc_to_page() backport for 2.4

[Hugh Dickins]

On Tue, 19 Mar 2002, Arjan van de Ven wrote:
> On Thu, Mar 14, 2002 at 02:46:39PM +0000, Hugh Dickins wrote:
> > 
> > Few modules take an interest in ptes, that's as it should be, and so
> > few modules build to different binaries with CONFIG_X86_PAE off or on
> > (modulo module versions).
> 
> Well dma_addr_t and some others also change size..... struct page also
> changes quite a bit

I believe it's CONFIG_HIGHMEM you're thinking of there: dma_addr_t
and struct page do depend on CONFIG_NOHIGHMEM/CONFIG_HIGHMEM in recent
kernels, but not on CONFIG_HIGHMEM4G/CONFIG_HIGHMEM64G(CONFIG_X86_PAE).

I don't know why it's CONFIG_HIGHMEM rather than CONFIG_HIGHMEM64G
that decides the u64-ness dma_addr_t.  There is a dmaaddr_high_t
which behaves more expectedly, but it's not so widely used.

Hugh