Re: [RFC][patch 0/2] mm: remove PageReserved

From: Russell King
Date: Tue Aug 09 2005 - 02:10:27 EST


On Tue, Aug 09, 2005 at 02:59:53PM +1000, Nick Piggin wrote:
> That would work for swsusp, but there are other users that want to
> know if a struct page is valid ram (eg. ioremap), so in that case
> swsusp would not be able to mess with the flag.

The usage of "valid ram" here is confusing - that's not what PageReserved
is all about. It's about valid RAM which is managed by method other
than the usual page counting. Non-reserved RAM is also valid RAM, but
is managed by the kernel in the usual way.

The former is available for remap_pfn_range and ioremap, the latter is
not.

On the other hand, the validity of an apparant RAM address can only be
tested using its pfn with pfn_valid().

Can we straighten out the terminology so it's less confusing please?

--
Russell King
Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/
maintainer of: 2.6 Serial core
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/