From c6b6f363f7b24aa448994e3a65c4d5b3116acfcc Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 31 Oct 2013 17:25:04 +0100 Subject: [PATCH] x86/mm/pageattr: Add a PTE pagetable populating function Handle last level by unconditionally writing the PTEs into the PTE page while paying attention to the NX bit. Signed-off-by: Borislav Petkov Signed-off-by: Matt Fleming --- arch/x86/mm/pageattr.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 968398b023c0..2a1308a8c072 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -686,7 +686,27 @@ static int alloc_pmd_page(pud_t *pud) return 0; } -#define populate_pte(cpa, start, end, pages, pmd, pgprot) do {} while (0) +static void populate_pte(struct cpa_data *cpa, + unsigned long start, unsigned long end, + unsigned num_pages, pmd_t *pmd, pgprot_t pgprot) +{ + pte_t *pte; + + pte = pte_offset_kernel(pmd, start); + + while (num_pages-- && start < end) { + + /* deal with the NX bit */ + if (!(pgprot_val(pgprot) & _PAGE_NX)) + cpa->pfn &= ~_PAGE_NX; + + set_pte(pte, pfn_pte(cpa->pfn >> PAGE_SHIFT, pgprot)); + + start += PAGE_SIZE; + cpa->pfn += PAGE_SIZE; + pte++; + } +} static int populate_pmd(struct cpa_data *cpa, unsigned long start, unsigned long end,