Merge remote-tracking branches 'regulator/topic/discharge', 'regulator/topic/fan53555...

[mirror_ubuntu-zesty-kernel.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index 2f2415a7a688da595a996a01d0ae0e1f0f955454..76d1ec29149bf25f5e6ffe3e56e86467efccc641 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2664,12 +2664,29 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
        if (!vma || !(vma->vm_flags & VM_SHARED))
                goto out;
 
-       if (start < vma->vm_start || start + size > vma->vm_end)
+       if (start < vma->vm_start)
                goto out;
 
-       if (pgoff == linear_page_index(vma, start)) {
-               ret = 0;
-               goto out;
+       if (start + size > vma->vm_end) {
+               struct vm_area_struct *next;
+
+               for (next = vma->vm_next; next; next = next->vm_next) {
+                       /* hole between vmas ? */
+                       if (next->vm_start != next->vm_prev->vm_end)
+                               goto out;
+
+                       if (next->vm_file != vma->vm_file)
+                               goto out;
+
+                       if (next->vm_flags != vma->vm_flags)
+                               goto out;
+
+                       if (start + size <= next->vm_end)
+                               break;
+               }
+
+               if (!next)
+                       goto out;
        }
 
        prot |= vma->vm_flags & VM_READ ? PROT_READ : 0;
@@ -2679,9 +2696,16 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
        flags &= MAP_NONBLOCK;
        flags |= MAP_SHARED | MAP_FIXED | MAP_POPULATE;
        if (vma->vm_flags & VM_LOCKED) {
+               struct vm_area_struct *tmp;
                flags |= MAP_LOCKED;
+
                /* drop PG_Mlocked flag for over-mapped range */
-               munlock_vma_pages_range(vma, start, start + size);
+               for (tmp = vma; tmp->vm_start >= start + size;
+                               tmp = tmp->vm_next) {
+                       munlock_vma_pages_range(tmp,
+                                       max(tmp->vm_start, start),
+                                       min(tmp->vm_end, start + size));
+               }
        }
 
        file = get_file(vma->vm_file);