dmaengine: fix dmaengine_unmap failure
The count which is used to get_unmap_data maybe not the same as the
count computed in dmaengine_unmap which causes to free data in a
wrong pool.
This patch fixes this issue by keeping the map count with unmap_data
structure and use this count to get the pool.
Cc: <stable@vger.kernel.org>
Signed-off-by: Xuelin Shi <xuelin.shi@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index a886713..d5d30ed 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -1009,6 +1009,7 @@
dma_unmap_page(dev, unmap->addr[i], unmap->len,
DMA_BIDIRECTIONAL);
}
+ cnt = unmap->map_cnt;
mempool_free(unmap, __get_unmap_pool(cnt)->pool);
}
@@ -1074,6 +1075,7 @@
memset(unmap, 0, sizeof(*unmap));
kref_init(&unmap->kref);
unmap->dev = dev;
+ unmap->map_cnt = nr;
return unmap;
}
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 8300fb8..72cb0dd 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -429,6 +429,7 @@
typedef void (*dma_async_tx_callback)(void *dma_async_param);
struct dmaengine_unmap_data {
+ u8 map_cnt;
u8 to_cnt;
u8 from_cnt;
u8 bidi_cnt;
