[PATCH 3.12 104/182] mtip32xx: Unmap the DMA segments before completing the IO request

From: Jiri Slaby
Date: Tue May 13 2014 - 06:21:52 EST


From: Felipe Franciosi <felipe@xxxxxxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 368c89d7ac70f937c93cd6f3b65bcfdfb3ba794f upstream.

If the buffers are unmapped after completing a request, then stale data
might be in the request.

Signed-off-by: Felipe Franciosi <felipe@xxxxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/block/mtip32xx/mtip32xx.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index bd3d20741958..4d26c25aa9c5 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -621,6 +621,12 @@ static void mtip_timeout_function(unsigned long int data)
*/
writel(1 << bit, port->completed[group]);

+ /* Unmap the DMA scatter list entries */
+ dma_unmap_sg(&port->dd->pdev->dev,
+ command->sg,
+ command->scatter_ents,
+ command->direction);
+
/* Call the async completion callback. */
if (likely(command->async_callback))
command->async_callback(command->async_data,
@@ -628,12 +634,6 @@ static void mtip_timeout_function(unsigned long int data)
command->async_callback = NULL;
command->comp_func = NULL;

- /* Unmap the DMA scatter list entries */
- dma_unmap_sg(&port->dd->pdev->dev,
- command->sg,
- command->scatter_ents,
- command->direction);
-
/*
* Clear the allocated bit and active tag for the
* command.
@@ -711,6 +711,12 @@ static void mtip_async_complete(struct mtip_port *port,
"Command tag %d failed due to TFE\n", tag);
}

+ /* Unmap the DMA scatter list entries */
+ dma_unmap_sg(&dd->pdev->dev,
+ command->sg,
+ command->scatter_ents,
+ command->direction);
+
/* Upper layer callback */
if (likely(command->async_callback))
command->async_callback(command->async_data, cb_status);
@@ -718,12 +724,6 @@ static void mtip_async_complete(struct mtip_port *port,
command->async_callback = NULL;
command->comp_func = NULL;

- /* Unmap the DMA scatter list entries */
- dma_unmap_sg(&dd->pdev->dev,
- command->sg,
- command->scatter_ents,
- command->direction);
-
/* Clear the allocated and active bits for the command */
atomic_set(&port->commands[tag].active, 0);
release_slot(port, tag);
--
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/