iomap: add IOMAP_F_NEW flag

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index f96c8ff..ac677d0 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -1000,6 +1000,7 @@
 		if (error)
 			return error;
 
+		iomap->flags = IOMAP_F_NEW;
 		trace_xfs_iomap_alloc(ip, offset, length, 0, &imap);
 	} else {
 		ASSERT(nimaps);
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 3d70ece..14d7067 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -22,6 +22,7 @@
  * Flags for iomap mappings:
  */
 #define IOMAP_F_MERGED	0x01	/* contains multiple blocks/extents */
+#define IOMAP_F_NEW	0x02	/* blocks have been newly allocated */
 
 /*
  * Magic value for blkno: