Merge tag 'renesas-boards-cleanups2-for-v3.19' of git://git.kernel.org/pub/scm/linux...

[firefly-linux-kernel-4.4.55.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index 93d28c7e54201de5549dab1a3dd696d785a06302..87e82b38453c2cbca83f1dd7ad472c02b6a73b77 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -89,6 +89,25 @@ pgprot_t vm_get_page_prot(unsigned long vm_flags)
 }
 EXPORT_SYMBOL(vm_get_page_prot);
 
+static pgprot_t vm_pgprot_modify(pgprot_t oldprot, unsigned long vm_flags)
+{
+       return pgprot_modify(oldprot, vm_get_page_prot(vm_flags));
+}
+
+/* Update vma->vm_page_prot to reflect vma->vm_flags. */
+void vma_set_page_prot(struct vm_area_struct *vma)
+{
+       unsigned long vm_flags = vma->vm_flags;
+
+       vma->vm_page_prot = vm_pgprot_modify(vma->vm_page_prot, vm_flags);
+       if (vma_wants_writenotify(vma)) {
+               vm_flags &= ~VM_SHARED;
+               vma->vm_page_prot = vm_pgprot_modify(vma->vm_page_prot,
+                                                    vm_flags);
+       }
+}
+
+
 int sysctl_overcommit_memory __read_mostly = OVERCOMMIT_GUESS;  /* heuristic overcommit */
 int sysctl_overcommit_ratio __read_mostly = 50;        /* default is 50% */
 unsigned long sysctl_overcommit_kbytes __read_mostly;
@@ -1061,7 +1080,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
                                end, prev->vm_pgoff, NULL);
                if (err)
                        return NULL;
-               khugepaged_enter_vma_merge(prev);
+               khugepaged_enter_vma_merge(prev, vm_flags);
                return prev;
        }
 
@@ -1080,7 +1099,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm,
                                next->vm_pgoff - pglen, NULL);
                if (err)
                        return NULL;
-               khugepaged_enter_vma_merge(area);
+               khugepaged_enter_vma_merge(area, vm_flags);
                return area;
        }
 
@@ -1475,11 +1494,16 @@ int vma_wants_writenotify(struct vm_area_struct *vma)
        if (vma->vm_ops && vma->vm_ops->page_mkwrite)
                return 1;
 
-       /* The open routine did something to the protections already? */
+       /* The open routine did something to the protections that pgprot_modify
+        * won't preserve? */
        if (pgprot_val(vma->vm_page_prot) !=
-           pgprot_val(vm_get_page_prot(vm_flags)))
+           pgprot_val(vm_pgprot_modify(vma->vm_page_prot, vm_flags)))
                return 0;
 
+       /* Do we need to track softdirty? */
+       if (IS_ENABLED(CONFIG_MEM_SOFT_DIRTY) && !(vm_flags & VM_SOFTDIRTY))
+               return 1;
+
        /* Specialty mapping? */
        if (vm_flags & VM_PFNMAP)
                return 0;
@@ -1615,21 +1639,6 @@ munmap_back:
                        goto free_vma;
        }
 
-       if (vma_wants_writenotify(vma)) {
-               pgprot_t pprot = vma->vm_page_prot;
-
-               /* Can vma->vm_page_prot have changed??
-                *
-                * Answer: Yes, drivers may have changed it in their
-                *         f_op->mmap method.
-                *
-                * Ensures that vmas marked as uncached stay that way.
-                */
-               vma->vm_page_prot = vm_get_page_prot(vm_flags & ~VM_SHARED);
-               if (pgprot_val(pprot) == pgprot_val(pgprot_noncached(pprot)))
-                       vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
-       }
-
        vma_link(mm, vma, prev, rb_link, rb_parent);
        /* Once vma denies write, undo our temporary denial count */
        if (file) {
@@ -1663,6 +1672,8 @@ out:
         */
        vma->vm_flags |= VM_SOFTDIRTY;
 
+       vma_set_page_prot(vma);
+
        return addr;
 
 unmap_and_free_vma:
@@ -2197,7 +2208,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
                }
        }
        vma_unlock_anon_vma(vma);
-       khugepaged_enter_vma_merge(vma);
+       khugepaged_enter_vma_merge(vma, vma->vm_flags);
        validate_mm(vma->vm_mm);
        return error;
 }
@@ -2266,7 +2277,7 @@ int expand_downwards(struct vm_area_struct *vma,
                }
        }
        vma_unlock_anon_vma(vma);
-       khugepaged_enter_vma_merge(vma);
+       khugepaged_enter_vma_merge(vma, vma->vm_flags);
        validate_mm(vma->vm_mm);
        return error;
 }