dmaengine: fsl_raid: move unmap to before callback

Completion callback should happen after dma_descriptor_unmap() has
happened. This allow the cache invalidate to happen and ensure that
the data accessed by the upper layer is in memory that was from DMA
rather than stale data. On some architecture this is done by the
hardware, however we should make the code consistent to not cause
confusion.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Cc: Xuelin Shi <xuelin.shi@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/fsl_raid.c

@@ -135,8 +135,8 @@ static void fsl_re_issue_pending(struct dma_chan *chan)
 static void fsl_re_desc_done(struct fsl_re_desc *desc)
 {
 	dma_cookie_complete(&desc->async_tx);
-	dmaengine_desc_get_callback_invoke(&desc->async_tx, NULL);
 	dma_descriptor_unmap(&desc->async_tx);
+	dmaengine_desc_get_callback_invoke(&desc->async_tx, NULL);
 }
 
 static void fsl_re_cleanup_descs(struct fsl_re_chan *re_chan)