Commit 43a432b1 authored Apr 09, 2009 by Suresh Siddha Committed by Ingo Molnar Apr 10, 2009

x86, CPA: Change idmap attribute before ioremap attribute setup



Change the identity mapping with the requested attribute first, before
we setup the virtual memory mapping with the new requested attribute.

This makes sure that there is no window when identity map'ed attribute
may disagree with ioremap range on the attribute type.

This also avoids doing cpa on the ioremap'ed address twice (first in
ioremap_page_range and then in ioremap_change_attr using vaddr), and
should improve ioremap performance a bit.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
LKML-Reference: <20090409212708.373330000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent a0d22f48

arch/x86/mm/ioremap.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -280,15 +280,16 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
		return NULL;
		area->phys_addr = phys_addr;
		vaddr = (unsigned long) area->addr;
		if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) {

		if (kernel_map_sync_memtype(phys_addr, size, prot_val)) {
		free_memtype(phys_addr, phys_addr + size);
		free_vm_area(area);
		return NULL;
		}

		if (ioremap_change_attr(vaddr, size, prot_val) < 0) {
		if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) {
		free_memtype(phys_addr, phys_addr + size);
		vunmap(area->addr);
		free_vm_area(area);
		return NULL;
		}

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