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-rw-r--r--mm/memory.c21
1 files changed, 4 insertions, 17 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 6fe77ac..4e1c673 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -811,18 +811,15 @@ static struct page *__follow_page(struct mm_struct *mm, unsigned long address,
pte = *ptep;
pte_unmap(ptep);
if (pte_present(pte)) {
- if (write && !pte_write(pte))
+ if (write && !pte_dirty(pte))
goto out;
if (read && !pte_read(pte))
goto out;
pfn = pte_pfn(pte);
if (pfn_valid(pfn)) {
page = pfn_to_page(pfn);
- if (accessed) {
- if (write && !pte_dirty(pte) &&!PageDirty(page))
- set_page_dirty(page);
+ if (accessed)
mark_page_accessed(page);
- }
return page;
}
}
@@ -941,10 +938,9 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
spin_lock(&mm->page_table_lock);
do {
struct page *page;
- int lookup_write = write;
cond_resched_lock(&mm->page_table_lock);
- while (!(page = follow_page(mm, start, lookup_write))) {
+ while (!(page = follow_page(mm, start, write))) {
/*
* Shortcut for anonymous pages. We don't want
* to force the creation of pages tables for
@@ -952,8 +948,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
* nobody touched so far. This is important
* for doing a core dump for these mappings.
*/
- if (!lookup_write &&
- untouched_anonymous_page(mm,vma,start)) {
+ if (!write && untouched_anonymous_page(mm,vma,start)) {
page = ZERO_PAGE(start);
break;
}
@@ -972,14 +967,6 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
default:
BUG();
}
- /*
- * Now that we have performed a write fault
- * and surely no longer have a shared page we
- * shouldn't write, we shouldn't ignore an
- * unwritable page in the page table if
- * we are forcing write access.
- */
- lookup_write = write && !force;
spin_lock(&mm->page_table_lock);
}
if (pages) {
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