ioatdma: fix "ioatdma frees DMA memory with wrong function"

as reported by Alexander Beregalov <a.beregalov@gmail.com>

ioatdma 0000:00:08.0: DMA-API: device driver frees DMA memory with
wrong function [device address=0x000000007f76f800] [size=2000 bytes]
[map
ped as single] [unmapped as page]

The ioatdma driver was unmapping all regions
(either allocated as page or single) using unmap_page.
This patch lets dma driver recognize if unmap_single or unmap_page should be used.
It introduces two new dma control flags:
DMA_COMPL_SRC_UNMAP_SINGLE and DMA_COMPL_DEST_UNMAP_SINGLE.
They should be set to indicate dma driver to do dma-unmapping as single
(first one for the source, tha latter for the destination).
If respective flag is not set, the driver assumes dma-unmapping as page.

Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Reported-by: Alexander Beregalov <a.beregalov@gmail.com>
Tested-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 2e2aa3df170..ffefba81c81 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -78,12 +78,18 @@ enum dma_transaction_type {
  *      dependency chains
  * @DMA_COMPL_SKIP_SRC_UNMAP - set to disable dma-unmapping the source buffer(s)
  * @DMA_COMPL_SKIP_DEST_UNMAP - set to disable dma-unmapping the destination(s)
+ * @DMA_COMPL_SRC_UNMAP_SINGLE - set to do the source dma-unmapping as single
+ *      (if not set, do the source dma-unmapping as page)
+ * @DMA_COMPL_DEST_UNMAP_SINGLE - set to do the destination dma-unmapping as single
+ *      (if not set, do the destination dma-unmapping as page)
  */
 enum dma_ctrl_flags {
         DMA_PREP_INTERRUPT = (1 << 0),
         DMA_CTRL_ACK = (1 << 1),
         DMA_COMPL_SKIP_SRC_UNMAP = (1 << 2),
         DMA_COMPL_SKIP_DEST_UNMAP = (1 << 3),
+        DMA_COMPL_SRC_UNMAP_SINGLE = (1 << 4),
+        DMA_COMPL_DEST_UNMAP_SINGLE = (1 << 5),
 };
 
 /**