From 50020fb6324465e478d6c8cdbf3c695f0a60358d Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 2 Sep 2009 15:38:40 +0200 Subject: x86/amd-iommu: Introduce increase_address_space function This function will be used to increase the address space size of a protection domain. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 5eab6a84b9c..fc97b51f028 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -1324,6 +1324,33 @@ static void update_domain(struct protection_domain *domain) domain->updated = false; } +/* + * This function is used to add another level to an IO page table. Adding + * another level increases the size of the address space by 9 bits to a size up + * to 64 bits. + */ +static bool increase_address_space(struct protection_domain *domain, + gfp_t gfp) +{ + u64 *pte; + + if (domain->mode == PAGE_MODE_6_LEVEL) + /* address space already 64 bit large */ + return false; + + pte = (void *)get_zeroed_page(gfp); + if (!pte) + return false; + + *pte = PM_LEVEL_PDE(domain->mode, + virt_to_phys(domain->pt_root)); + domain->pt_root = pte; + domain->mode += 1; + domain->updated = true; + + return true; +} + /* * If the pte_page is not yet allocated this function is called */ -- cgit v1.2.3