mm: use mm_populate() for blocking remap_file_pages()

Signed-off-by: Michel Lespinasse <walken@google.com> Reviewed-by: Rik van Riel <riel@redhat.com> Tested-by: Andy Lutomirski <luto@amacapital.net> Cc: Greg Ungerer <gregungerer@westnet.com.au> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: use mm_populate() for blocking remap_file_pages()
Signed-off-by: Michel Lespinasse <walken@google.com> Reviewed-by: Rik van Riel <riel@redhat.com> Tested-by: Andy Lutomirski <luto@amacapital.net> Cc: Greg Ungerer <gregungerer@westnet.com.au> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michel Lespinasse · Linus Torvalds
1 parent bebeb3d68b
Showing 1 changed file with 6 additions and 16 deletions Side-by-side Diff
mm/fremap.c
@@ -129,6 +129,7 @@
 	struct vm_area_struct *vma;
 	int err = -EINVAL;
 	int has_write_lock = 0;
+	vm_flags_t vm_flags;
  
 	if (prot)
 		return err;
  
  
  
@@ -228,30 +229,16 @@
 		/*
 		 * drop PG_Mlocked flag for over-mapped range
 		 */
-		vm_flags_t saved_flags = vma->vm_flags;
 		if (!has_write_lock)
 			goto get_write_lock;
+		vm_flags = vma->vm_flags;
 		munlock_vma_pages_range(vma, start, start + size);
-		vma->vm_flags = saved_flags;
+		vma->vm_flags = vm_flags;
 	}
  
 	mmu_notifier_invalidate_range_start(mm, start, start + size);
 	err = vma->vm_ops->remap_pages(vma, start, size, pgoff);
 	mmu_notifier_invalidate_range_end(mm, start, start + size);
-	if (!err) {
-		if (vma->vm_flags & VM_LOCKED) {
-			/*
-			 * might be mapping previously unmapped range of file
-			 */
-			mlock_vma_pages_range(vma, start, start + size);
-		} else if (!(flags & MAP_NONBLOCK)) {
-			if (unlikely(has_write_lock)) {
-				downgrade_write(&mm->mmap_sem);
-				has_write_lock = 0;
-			}
-			make_pages_present(start, start+size);
-		}
-	}
  
 	/*
 	 * We can't clear VM_NONLINEAR because we'd have to do
  
@@ -260,10 +247,13 @@
 	 */
  
 out:
+	vm_flags = vma->vm_flags;
 	if (likely(!has_write_lock))
 		up_read(&mm->mmap_sem);
 	else
 		up_write(&mm->mmap_sem);
+	if (!err && ((vm_flags & VM_LOCKED) || !(flags & MAP_NONBLOCK)))
+		mm_populate(start, size);
  
 	return err;
 }
...	...	@@ -129,6 +129,7 @@
129	129	struct vm_area_struct *vma;
130	130	int err = -EINVAL;
131	131	int has_write_lock = 0;
	132	+ vm_flags_t vm_flags;
132	133
133	134	if (prot)
134	135	return err;
135	136
136	137
137	138
...	...	@@ -228,30 +229,16 @@
228	229	/*
229	230	* drop PG_Mlocked flag for over-mapped range
230	231	*/
231		- vm_flags_t saved_flags = vma->vm_flags;
232	232	if (!has_write_lock)
233	233	goto get_write_lock;
	234	+ vm_flags = vma->vm_flags;
234	235	munlock_vma_pages_range(vma, start, start + size);
235		- vma->vm_flags = saved_flags;
	236	+ vma->vm_flags = vm_flags;
236	237	}
237	238
238	239	mmu_notifier_invalidate_range_start(mm, start, start + size);
239	240	err = vma->vm_ops->remap_pages(vma, start, size, pgoff);
240	241	mmu_notifier_invalidate_range_end(mm, start, start + size);
241		- if (!err) {
242		- if (vma->vm_flags & VM_LOCKED) {
243		- /*
244		- * might be mapping previously unmapped range of file
245		- */
246		- mlock_vma_pages_range(vma, start, start + size);
247		- } else if (!(flags & MAP_NONBLOCK)) {
248		- if (unlikely(has_write_lock)) {
249		- downgrade_write(&mm->mmap_sem);
250		- has_write_lock = 0;
251		- }
252		- make_pages_present(start, start+size);
253		- }
254		- }
255	242
256	243	/*
257	244	* We can't clear VM_NONLINEAR because we'd have to do
258	245
...	...	@@ -260,10 +247,13 @@
260	247	*/
261	248
262	249	out:
	250	+ vm_flags = vma->vm_flags;
263	251	if (likely(!has_write_lock))
264	252	up_read(&mm->mmap_sem);
265	253	else
266	254	up_write(&mm->mmap_sem);
	255	+ if (!err && ((vm_flags & VM_LOCKED) \|\| !(flags & MAP_NONBLOCK)))
	256	+ mm_populate(start, size);
267	257
268	258	return err;
269	259	}