Merge remote-tracking branch 'asoc/topic/const' into asoc-next

[sfrench/cifs-2.6.git] / fs / dax.c

diff --git a/fs/dax.c b/fs/dax.c
index 306c2b603fb8aa8845558a2bf8226523e5282cdb..865d42c63e23e4746c6658fbe2746fd17ade11f9 100644 (file)
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1383,6 +1383,16 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
 
        trace_dax_pmd_fault(inode, vmf, max_pgoff, 0);
 
+       /*
+        * Make sure that the faulting address's PMD offset (color) matches
+        * the PMD offset from the start of the file.  This is necessary so
+        * that a PMD range in the page table overlaps exactly with a PMD
+        * range in the radix tree.
+        */
+       if ((vmf->pgoff & PG_PMD_COLOUR) !=
+           ((vmf->address >> PAGE_SHIFT) & PG_PMD_COLOUR))
+               goto fallback;
+
        /* Fall back to PTEs if we're going to COW */
        if (write && !(vma->vm_flags & VM_SHARED))
                goto fallback;