[PATCH] add vm_insert_pfn()

[linux-drm-fsl-dcu.git] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index 563792f4f687e6e6dde9f98aaf87d3116b82daff..8b8f0d2b453d03a9749a48e515d8d972f354dfb8 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -678,7 +678,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
                                if (pte_dirty(ptent))
                                        set_page_dirty(page);
                                if (pte_young(ptent))
-                                       mark_page_accessed(page);
+                                       SetPageReferenced(page);
                                file_rss--;
                        }
                        page_remove_rmap(page, vma);
@@ -1091,7 +1091,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                        if (pages) {
                                pages[i] = page;
 
-                               flush_anon_page(page, start);
+                               flush_anon_page(vma, page, start);
                                flush_dcache_page(page);
                        }
                        if (vmas)
@@ -1277,6 +1277,51 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, struct page *
 }
 EXPORT_SYMBOL(vm_insert_page);
 
+/**
+ * vm_insert_pfn - insert single pfn into user vma
+ * @vma: user vma to map to
+ * @addr: target user address of this page
+ * @pfn: source kernel pfn
+ *
+ * Similar to vm_inert_page, this allows drivers to insert individual pages
+ * they've allocated into a user vma. Same comments apply.
+ *
+ * This function should only be called from a vm_ops->fault handler, and
+ * in that case the handler should return NULL.
+ */
+int vm_insert_pfn(struct vm_area_struct *vma, unsigned long addr,
+               unsigned long pfn)
+{
+       struct mm_struct *mm = vma->vm_mm;
+       int retval;
+       pte_t *pte, entry;
+       spinlock_t *ptl;
+
+       BUG_ON(!(vma->vm_flags & VM_PFNMAP));
+       BUG_ON(is_cow_mapping(vma->vm_flags));
+
+       retval = -ENOMEM;
+       pte = get_locked_pte(mm, addr, &ptl);
+       if (!pte)
+               goto out;
+       retval = -EBUSY;
+       if (!pte_none(*pte))
+               goto out_unlock;
+
+       /* Ok, finally just insert the thing.. */
+       entry = pfn_pte(pfn, vma->vm_page_prot);
+       set_pte_at(mm, addr, pte, entry);
+       update_mmu_cache(vma, addr, entry);
+
+       retval = 0;
+out_unlock:
+       pte_unmap_unlock(pte, ptl);
+
+out:
+       return retval;
+}
+EXPORT_SYMBOL(vm_insert_pfn);
+
 /*
  * maps a range of physical memory into the requested pages. the old
  * mappings are removed. any references to nonexistent pages results
@@ -1531,8 +1576,6 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
                        if (vma->vm_ops->page_mkwrite(vma, old_page) < 0)
                                goto unwritable_page;
 
-                       page_cache_release(old_page);
-
                        /*
                         * Since we dropped the lock we need to revalidate
                         * the PTE as someone else may have changed it.  If
@@ -1541,6 +1584,7 @@ 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))
                                goto unlock;
                }
@@ -1776,9 +1820,7 @@ restart:
 }
 
 /**
- * unmap_mapping_range - unmap the portion of all mmaps
- * in the specified address_space corresponding to the specified
- * page range in the underlying file.
+ * unmap_mapping_range - unmap the portion of all mmaps in the specified address_space corresponding to the specified page range in the underlying file.
  * @mapping: the address space containing mmaps to be unmapped.
  * @holebegin: byte in first page to unmap, relative to the start of
  * the underlying file.  This will be rounded down to a PAGE_SIZE
@@ -2606,8 +2648,15 @@ static int __init gate_vma_init(void)
        gate_vma.vm_mm = NULL;
        gate_vma.vm_start = FIXADDR_USER_START;
        gate_vma.vm_end = FIXADDR_USER_END;
-       gate_vma.vm_page_prot = PAGE_READONLY;
-       gate_vma.vm_flags = 0;
+       gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
+       gate_vma.vm_page_prot = __P101;
+       /*
+        * Make sure the vDSO gets into every core dump.
+        * Dumping its contents makes post-mortem fully interpretable later
+        * without matching up the same kernel and hardware config to see
+        * what PC values meant.
+        */
+       gate_vma.vm_flags |= VM_ALWAYSDUMP;
        return 0;
 }
 __initcall(gate_vma_init);