Do not account for the address space used by hugetlbfs using VM_ACCOUNT

[linux-2.6.git] / mm / mprotect.c

diff --git a/mm/mprotect.c b/mm/mprotect.c
index abd645a3b0a021bb34d5de49cff94efae109966c..258197b76fb4142d01b81d7871fddbca80510114 100644 (file)
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -4,7 +4,7 @@
  *  (C) Copyright 1994 Linus Torvalds
  *  (C) Copyright 2002 Christoph Hellwig
  *
- *  Address space accounting code      <alan@redhat.com>
+ *  Address space accounting code      <alan@lxorguk.ukuu.org.uk>
  *  (C) Copyright 2002 Red Hat Inc, All Rights Reserved
  */
 
@@ -21,6 +21,8 @@
 #include <linux/syscalls.h>
 #include <linux/swap.h>
 #include <linux/swapops.h>
+#include <linux/mmu_notifier.h>
+#include <linux/migrate.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/cacheflush.h>
@@ -58,8 +60,7 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd,
                                ptent = pte_mkwrite(ptent);
 
                        ptep_modify_prot_commit(mm, addr, pte, ptent);
-#ifdef CONFIG_MIGRATION
-               } else if (!pte_file(oldpte)) {
+               } else if (PAGE_MIGRATION && !pte_file(oldpte)) {
                        swp_entry_t entry = pte_to_swp_entry(oldpte);
 
                        if (is_write_migration_entry(entry)) {
@@ -71,9 +72,7 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd,
                                set_pte_at(mm, addr, pte,
                                        swp_entry_to_pte(entry));
                        }
-#endif
                }
-
        } while (pte++, addr += PAGE_SIZE, addr != end);
        arch_leave_lazy_mmu_mode();
        pte_unmap_unlock(pte - 1, ptl);
@@ -152,10 +151,11 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev,
        /*
         * If we make a private mapping writable we increase our commit;
         * but (without finer accounting) cannot reduce our commit if we
-        * make it unwritable again.
+        * make it unwritable again. hugetlb mapping were accounted for
+        * even if read-only so there is no need to account for them here
         */
        if (newflags & VM_WRITE) {
-               if (!(oldflags & (VM_ACCOUNT|VM_WRITE|
+               if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_HUGETLB|
                                                VM_SHARED|VM_NORESERVE))) {
                        charged = nrpages;
                        if (security_vm_enough_memory(charged))
@@ -203,10 +203,12 @@ success:
                dirty_accountable = 1;
        }
 
+       mmu_notifier_invalidate_range_start(mm, start, end);
        if (is_vm_hugetlb_page(vma))
                hugetlb_change_protection(vma, start, end, vma->vm_page_prot);
        else
                change_protection(vma, start, end, vma->vm_page_prot, dirty_accountable);
+       mmu_notifier_invalidate_range_end(mm, start, end);
        vm_stat_account(mm, oldflags, vma->vm_file, -nrpages);
        vm_stat_account(mm, newflags, vma->vm_file, nrpages);
        return 0;
@@ -216,8 +218,8 @@ fail:
        return error;
 }
 
-asmlinkage long
-sys_mprotect(unsigned long start, size_t len, unsigned long prot)
+SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len,
+               unsigned long, prot)
 {
        unsigned long vm_flags, nstart, end, tmp, reqprot;
        struct vm_area_struct *vma, *prev;