From fcea424d31868a78366ad5ee0cb3cc2a4cbe689b Mon Sep 17 00:00:00 2001 From: Arjan van dev Ven Date: Wed, 6 Feb 2008 05:16:00 +0100 Subject: fix historic ioremap() abuse in AGP Several AGP drivers right now use ioremap_nocache() on kernel ram in order to turn a page of regular memory uncached. There are two problems with this: 1) This is a total nightmare for the ioremap() implementation to keep various mappings of the same page coherent. 2) It's a total nightmare for the AGP code since it adds a ton of complexity in terms of keeping track of 2 different pointers to the same thing, in terms of error handling etc etc. This patch fixes this by making the AGP drivers use the new set_memory_XX APIs instead. Note: amd-k7-agp.c is built on Alpha too, and generic.c is built on ia64 as well, which do not yet have the set_memory_*() APIs, so for them some we have a few ugly #ifdefs - hopefully they'll be fixed soon. Signed-off-by: Arjan van de Ven Signed-off-by: Ingo Molnar Signed-off-by: Dave Airlie --- arch/x86/mm/ioremap.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/mm') diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 9f42d7e9c158..69f4981db80f 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -126,6 +126,8 @@ static void __iomem *__ioremap(unsigned long phys_addr, unsigned long size, return NULL; } + WARN_ON_ONCE(page_is_ram(pfn)); + switch (mode) { case IOR_MODE_UNCACHED: default: -- cgit v1.2.2