x86, mce: Add boot options for corrected errors

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

diff --git a/mm/memory.c b/mm/memory.c
index cf6873e..4126dd1 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1971,6 +1971,15 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
                                ret = tmp;
                                goto unwritable_page;
                        }
+                       if (unlikely(!(tmp & VM_FAULT_LOCKED))) {
+                               lock_page(old_page);
+                               if (!old_page->mapping) {
+                                       ret = 0; /* retry the fault */
+                                       unlock_page(old_page);
+                                       goto unwritable_page;
+                               }
+                       } else
+                               VM_BUG_ON(!PageLocked(old_page));
 
                        /*
                         * Since we dropped the lock we need to revalidate
@@ -1980,9 +1989,11 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
                         */
                        page_table = pte_offset_map_lock(mm, pmd, address,
                                                         &ptl);
-                       page_cache_release(old_page);
-                       if (!pte_same(*page_table, orig_pte))
+                       if (!pte_same(*page_table, orig_pte)) {
+                               unlock_page(old_page);
+                               page_cache_release(old_page);
                                goto unlock;
+                       }
 
                        page_mkwrite = 1;
                }
@@ -2094,9 +2105,6 @@ gotten:
 unlock:
        pte_unmap_unlock(page_table, ptl);
        if (dirty_page) {
-               if (vma->vm_file)
-                       file_update_time(vma->vm_file);
-
                /*
                 * Yes, Virginia, this is actually required to prevent a race
                 * with clear_page_dirty_for_io() from clearing the page dirty
@@ -2105,16 +2113,41 @@ unlock:
                 *
                 * do_no_page is protected similarly.
                 */
-               wait_on_page_locked(dirty_page);
-               set_page_dirty_balance(dirty_page, page_mkwrite);
+               if (!page_mkwrite) {
+                       wait_on_page_locked(dirty_page);
+                       set_page_dirty_balance(dirty_page, page_mkwrite);
+               }
                put_page(dirty_page);
+               if (page_mkwrite) {
+                       struct address_space *mapping = dirty_page->mapping;
+
+                       set_page_dirty(dirty_page);
+                       unlock_page(dirty_page);
+                       page_cache_release(dirty_page);
+                       if (mapping)    {
+                               /*
+                                * Some device drivers do not set page.mapping
+                                * but still dirty their pages
+                                */
+                               balance_dirty_pages_ratelimited(mapping);
+                       }
+               }
+
+               /* file_update_time outside page_lock */
+               if (vma->vm_file)
+                       file_update_time(vma->vm_file);
        }
        return ret;
 oom_free_new:
        page_cache_release(new_page);
 oom:
-       if (old_page)
+       if (old_page) {
+               if (page_mkwrite) {
+                       unlock_page(old_page);
+                       page_cache_release(old_page);
+               }
                page_cache_release(old_page);
+       }
        return VM_FAULT_OOM;
 
 unwritable_page:
@@ -2458,8 +2491,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
 
        if (mem_cgroup_try_charge_swapin(mm, page, GFP_KERNEL, &ptr)) {
                ret = VM_FAULT_OOM;
-               unlock_page(page);
-               goto out;
+               goto out_page;
        }
 
        /*
@@ -2521,6 +2553,7 @@ out:
 out_nomap:
        mem_cgroup_cancel_charge_swapin(ptr);
        pte_unmap_unlock(page_table, ptl);
+out_page:
        unlock_page(page);
        page_cache_release(page);
        return ret;
@@ -2664,27 +2697,22 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                                int tmp;
 
                                unlock_page(page);
-                               vmf.flags |= FAULT_FLAG_MKWRITE;
+                               vmf.flags = FAULT_FLAG_WRITE|FAULT_FLAG_MKWRITE;
                                tmp = vma->vm_ops->page_mkwrite(vma, &vmf);
                                if (unlikely(tmp &
                                          (VM_FAULT_ERROR | VM_FAULT_NOPAGE))) {
                                        ret = tmp;
-                                       anon = 1; /* no anon but release vmf.page */
-                                       goto out_unlocked;
-                               }
-                               lock_page(page);
-                               /*
-                                * XXX: this is not quite right (racy vs
-                                * invalidate) to unlock and relock the page
-                                * like this, however a better fix requires
-                                * reworking page_mkwrite locking API, which
-                                * is better done later.
-                                */
-                               if (!page->mapping) {
-                                       ret = 0;
-                                       anon = 1; /* no anon but release vmf.page */
-                                       goto out;
+                                       goto unwritable_page;
                                }
+                               if (unlikely(!(tmp & VM_FAULT_LOCKED))) {
+                                       lock_page(page);
+                                       if (!page->mapping) {
+                                               ret = 0; /* retry the fault */
+                                               unlock_page(page);
+                                               goto unwritable_page;
+                                       }
+                               } else
+                                       VM_BUG_ON(!PageLocked(page));
                                page_mkwrite = 1;
                        }
                }
@@ -2736,19 +2764,35 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
        pte_unmap_unlock(page_table, ptl);
 
 out:
-       unlock_page(vmf.page);
-out_unlocked:
-       if (anon)
-               page_cache_release(vmf.page);
-       else if (dirty_page) {
-               if (vma->vm_file)
-                       file_update_time(vma->vm_file);
+       if (dirty_page) {
+               struct address_space *mapping = page->mapping;
 
-               set_page_dirty_balance(dirty_page, page_mkwrite);
+               if (set_page_dirty(dirty_page))
+                       page_mkwrite = 1;
+               unlock_page(dirty_page);
                put_page(dirty_page);
+               if (page_mkwrite && mapping) {
+                       /*
+                        * Some device drivers do not set page.mapping but still
+                        * dirty their pages
+                        */
+                       balance_dirty_pages_ratelimited(mapping);
+               }
+
+               /* file_update_time outside page_lock */
+               if (vma->vm_file)
+                       file_update_time(vma->vm_file);
+       } else {
+               unlock_page(vmf.page);
+               if (anon)
+                       page_cache_release(vmf.page);
        }
 
        return ret;
+
+unwritable_page:
+       page_cache_release(page);
+       return ret;
 }
 
 static int do_linear_fault(struct mm_struct *mm, struct vm_area_struct *vma,