1 files changed, 51 insertions, 10 deletions

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 4774c7172ef4..f5695dc314f1 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -718,6 +718,38 @@ buffered:
 	return ret;
 }
 
+static void
+xfs_wait_dax_page(
+	struct inode		*inode,
+	bool			*did_unlock)
+{
+	struct xfs_inode        *ip = XFS_I(inode);
+
+	*did_unlock = true;
+	xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
+	schedule();
+	xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
+}
+
+static int
+xfs_break_dax_layouts(
+	struct inode		*inode,
+	uint			iolock,
+	bool			*did_unlock)
+{
+	struct page		*page;
+
+	ASSERT(xfs_isilocked(XFS_I(inode), XFS_MMAPLOCK_EXCL));
+
+	page = dax_layout_busy_page(inode->i_mapping);
+	if (!page)
+		return 0;
+
+	return ___wait_var_event(&page->_refcount,
+			atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
+			0, 0, xfs_wait_dax_page(inode, did_unlock));
+}
+
 int
 xfs_break_layouts(
 	struct inode		*inode,
@@ -725,19 +757,28 @@ xfs_break_layouts(
 	enum layout_break_reason reason)
 {
 	bool			retry;
+	int			error;
 
 	ASSERT(xfs_isilocked(XFS_I(inode), XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL));
 
-	switch (reason) {
-	case BREAK_UNMAP:
-		ASSERT(xfs_isilocked(XFS_I(inode), XFS_MMAPLOCK_EXCL));
-		/* fall through */
-	case BREAK_WRITE:
-		return xfs_break_leased_layouts(inode, iolock, &retry);
-	default:
-		WARN_ON_ONCE(1);
-		return -EINVAL;
-	}
+	do {
+		retry = false;
+		switch (reason) {
+		case BREAK_UNMAP:
+			error = xfs_break_dax_layouts(inode, *iolock, &retry);
+			if (error || retry)
+				break;
+			/* fall through */
+		case BREAK_WRITE:
+			error = xfs_break_leased_layouts(inode, iolock, &retry);
+			break;
+		default:
+			WARN_ON_ONCE(1);
+			error = -EINVAL;
+		}
+	} while (error == 0 && retry);
+
+	return error;
 }
 
 #define	XFS_FALLOC_FL_SUPPORTED						\