1 files changed, 15 insertions, 6 deletions

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index f0e8249722d4..db4acc1c3e73 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1514,18 +1514,27 @@ xfs_filemap_fault(
         struct vm_area_struct   *vma,
         struct vm_fault         *vmf)
 {
-        struct xfs_inode        *ip = XFS_I(file_inode(vma->vm_file));
+        struct inode            *inode = file_inode(vma->vm_file);
         int                     ret;
 
-        trace_xfs_filemap_fault(ip);
+        trace_xfs_filemap_fault(XFS_I(inode));
 
         /* DAX can shortcut the normal fault path on write faults! */
-        if ((vmf->flags & FAULT_FLAG_WRITE) && IS_DAX(VFS_I(ip)))
+        if ((vmf->flags & FAULT_FLAG_WRITE) && IS_DAX(inode))
                 return xfs_filemap_page_mkwrite(vma, vmf);
 
-        xfs_ilock(ip, XFS_MMAPLOCK_SHARED);
-        ret = filemap_fault(vma, vmf);
-        xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
+        xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
+        if (IS_DAX(inode)) {
+                /*
+                 * we do not want to trigger unwritten extent conversion on read
+                 * faults - that is unnecessary overhead and would also require
+                 * changes to xfs_get_blocks_direct() to map unwritten extent
+                 * ioend for conversion on read-only mappings.
+                 */
+                ret = __dax_fault(vma, vmf, xfs_get_blocks_direct, NULL);
+        } else
+                ret = filemap_fault(vma, vmf);
+        xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
 
         return ret;
 }