ipc,sem: use current->state helpers

[pandora-kernel.git] / mm / mprotect.c

diff --git a/mm/mprotect.c b/mm/mprotect.c
index ace9345..4472781 100644 (file)
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -75,37 +75,35 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
                oldpte = *pte;
                if (pte_present(oldpte)) {
                        pte_t ptent;
-                       bool updated = false;
 
-                       if (!prot_numa) {
-                               ptent = ptep_modify_prot_start(mm, addr, pte);
-                               if (pte_numa(ptent))
-                                       ptent = pte_mknonnuma(ptent);
-                               ptent = pte_modify(ptent, newprot);
-                               /*
-                                * Avoid taking write faults for pages we
-                                * know to be dirty.
-                                */
-                               if (dirty_accountable && pte_dirty(ptent) &&
-                                   (pte_soft_dirty(ptent) ||
-                                    !(vma->vm_flags & VM_SOFTDIRTY)))
-                                       ptent = pte_mkwrite(ptent);
-                               ptep_modify_prot_commit(mm, addr, pte, ptent);
-                               updated = true;
-                       } else {
+                       /*
+                        * Avoid trapping faults against the zero or KSM
+                        * pages. See similar comment in change_huge_pmd.
+                        */
+                       if (prot_numa) {
                                struct page *page;
 
                                page = vm_normal_page(vma, addr, oldpte);
-                               if (page && !PageKsm(page)) {
-                                       if (!pte_numa(oldpte)) {
-                                               ptep_set_numa(mm, addr, pte);
-                                               updated = true;
-                                       }
-                               }
+                               if (!page || PageKsm(page))
+                                       continue;
+
+                               /* Avoid TLB flush if possible */
+                               if (pte_protnone(oldpte))
+                                       continue;
                        }
-                       if (updated)
-                               pages++;
-               } else if (IS_ENABLED(CONFIG_MIGRATION) && !pte_file(oldpte)) {
+
+                       ptent = ptep_modify_prot_start(mm, addr, pte);
+                       ptent = pte_modify(ptent, newprot);
+
+                       /* Avoid taking write faults for known dirty pages */
+                       if (dirty_accountable && pte_dirty(ptent) &&
+                                       (pte_soft_dirty(ptent) ||
+                                        !(vma->vm_flags & VM_SOFTDIRTY))) {
+                               ptent = pte_mkwrite(ptent);
+                       }
+                       ptep_modify_prot_commit(mm, addr, pte, ptent);
+                       pages++;
+               } else if (IS_ENABLED(CONFIG_MIGRATION)) {
                        swp_entry_t entry = pte_to_swp_entry(oldpte);
 
                        if (is_write_migration_entry(entry)) {