[1/4] I/OAT: fix channel resources free for not allocated channels
Maciej Sosnowski [Fri, 7 Nov 2008 01:45:52 +0000 (01:45 +0000)]
If the ioatdma driver is loaded but not used it does not allocate descriptors.
Before it frees channel resources it should first be sure
that they have been previously allocated.

Cc: <stable@kernel.org>
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Tested-by: Tom Picard <tom.s.picard@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/dma/ioat_dma.c

index b0438c4..dbb8bbb 100644 (file)
@@ -807,6 +807,12 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
        struct ioat_desc_sw *desc, *_desc;
        int in_use_descs = 0;
 
+       /* Before freeing channel resources first check
+        * if they have been previously allocated for this channel.
+        */
+       if (ioat_chan->desccount == 0)
+               return;
+
        tasklet_disable(&ioat_chan->cleanup_task);
        ioat_dma_memcpy_cleanup(ioat_chan);
 
@@ -869,6 +875,7 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
        ioat_chan->last_completion = ioat_chan->completion_addr = 0;
        ioat_chan->pending = 0;
        ioat_chan->dmacount = 0;
+       ioat_chan->desccount = 0;
        ioat_chan->watchdog_completion = 0;
        ioat_chan->last_compl_desc_addr_hw = 0;
        ioat_chan->watchdog_tcp_cookie =