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| author | Thomas Petazzoni <thomas.petazzoni@free-electrons.com> | 2017-05-05 11:57:45 +0200 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2017-05-14 18:22:18 +0530 |
| commit | 2aab4e18152cd30cb5d2f4c27629fc8a04aed979 (patch) | |
| tree | aea9f8089f1fd2e386d0a871abacd7421590e715 | |
| parent | eb8df543e444492328f506adffc7dfe94111f1bd (diff) | |
| download | linux-2aab4e18152cd30cb5d2f4c27629fc8a04aed979.tar.bz2 | |
dmaengine: mv_xor_v2: properly handle wrapping in the array of HW descriptors
mv_xor_v2_tasklet() is looping over completed HW descriptors. Before the
loop, it initializes 'next_pending_hw_desc' to the first HW descriptor
to handle, and then the loop simply increments this point, without
taking care of wrapping when we reach the last HW descriptor. The
'pending_ptr' index was being wrapped back to 0 at the end, but it
wasn't used in each iteration of the loop to calculate
next_pending_hw_desc.
This commit fixes that, and makes next_pending_hw_desc a variable local
to the loop itself.
Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver")
Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
| -rw-r--r-- | drivers/dma/mv_xor_v2.c | 14 |
1 files changed, 4 insertions, 10 deletions
diff --git a/drivers/dma/mv_xor_v2.c b/drivers/dma/mv_xor_v2.c index e9280207ac19..bdfb36ecff81 100644 --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -560,7 +560,6 @@ static void mv_xor_v2_tasklet(unsigned long data) { struct mv_xor_v2_device *xor_dev = (struct mv_xor_v2_device *) data; int pending_ptr, num_of_pending, i; - struct mv_xor_v2_descriptor *next_pending_hw_desc = NULL; struct mv_xor_v2_sw_desc *next_pending_sw_desc = NULL; dev_dbg(xor_dev->dmadev.dev, "%s %d\n", __func__, __LINE__); @@ -568,17 +567,10 @@ static void mv_xor_v2_tasklet(unsigned long data) /* get the pending descriptors parameters */ num_of_pending = mv_xor_v2_get_pending_params(xor_dev, &pending_ptr); - /* next HW descriptor */ - next_pending_hw_desc = xor_dev->hw_desq_virt + pending_ptr; - /* loop over free descriptors */ for (i = 0; i < num_of_pending; i++) { - - if (pending_ptr > MV_XOR_V2_DESC_NUM) - pending_ptr = 0; - - if (next_pending_sw_desc != NULL) - next_pending_hw_desc++; + struct mv_xor_v2_descriptor *next_pending_hw_desc = + xor_dev->hw_desq_virt + pending_ptr; /* get the SW descriptor related to the HW descriptor */ next_pending_sw_desc = @@ -614,6 +606,8 @@ static void mv_xor_v2_tasklet(unsigned long data) /* increment the next descriptor */ pending_ptr++; + if (pending_ptr >= MV_XOR_V2_DESC_NUM) + pending_ptr = 0; } if (num_of_pending != 0) { |