x86, mm, Xen: Remove mapping_pagetable_reserve()

Page table area are pre-mapped now after
	x86, mm: setup page table in top-down
	x86, mm: Remove early_memremap workaround for page table accessing on 64bit

mapping_pagetable_reserve is not used anymore, so remove it.

Also remove operation in mask_rw_pte(), as modified allow_low_page
always return pages that are already mapped, moreover
xen_alloc_pte_init, xen_alloc_pmd_init, etc, will mark the page RO
before hooking it into the pagetable automatically.

-v2: add changelog about mask_rw_pte() from Stefano.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-27-git-send-email-yinghai@kernel.org
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 0 insertions, 28 deletions

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index dcf5f2dd91ec..bbb883f58bc4 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1178,20 +1178,6 @@ static void xen_exit_mmap(struct mm_struct *mm)
 
 static void xen_post_allocator_init(void);
 
-static __init void xen_mapping_pagetable_reserve(u64 start, u64 end)
-{
-        /* reserve the range used */
-        native_pagetable_reserve(start, end);
-
-        /* set as RW the rest */
-        printk(KERN_DEBUG "xen: setting RW the range %llx - %llx\n", end,
-                        PFN_PHYS(pgt_buf_top));
-        while (end < PFN_PHYS(pgt_buf_top)) {
-                make_lowmem_page_readwrite(__va(end));
-                end += PAGE_SIZE;
-        }
-}
-
 #ifdef CONFIG_X86_64
 static void __init xen_cleanhighmap(unsigned long vaddr,
                                     unsigned long vaddr_end)
@@ -1503,19 +1489,6 @@ static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 #else /* CONFIG_X86_64 */
 static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 {
-        unsigned long pfn = pte_pfn(pte);
-
-        /*
-         * If the new pfn is within the range of the newly allocated
-         * kernel pagetable, and it isn't being mapped into an
-         * early_ioremap fixmap slot as a freshly allocated page, make sure
-         * it is RO.
-         */
-        if (((!is_early_ioremap_ptep(ptep) &&
-                        pfn >= pgt_buf_start && pfn < pgt_buf_top)) ||
-                        (is_early_ioremap_ptep(ptep) && pfn != (pgt_buf_end - 1)))
-                pte = pte_wrprotect(pte);
-
         return pte;
 }
 #endif /* CONFIG_X86_64 */
@@ -2197,7 +2170,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
 
 void __init xen_init_mmu_ops(void)
 {
-        x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve;
         x86_init.paging.pagetable_init = xen_pagetable_init;
         pv_mmu_ops = xen_mmu_ops;