From 8be9e32b310cd8c4302991c8ff6692689c7d9d76 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Sun, 28 Oct 2012 00:49:32 +0900 Subject: [PATCH] dmatest: adjust invalid module parameters for number of source buffers DMA Engine test module has module parameters to set the number of source buffers for xor and pq operations. We can set these values larger than the maximum number of sources that the device can support. These values are not adjusted and the unsupported number of source buffers are passed to the device. But most drivers don't check it, so unexpected results will happen. This makes an appropriate adjustment for these module parameters before use. Signed-off-by: Akinobu Mita Cc: Vinod Koul Cc: Dan Williams Signed-off-by: Vinod Koul --- drivers/dma/dmatest.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c index 64b048d7fba7..3a8047b1f108 100644 --- a/drivers/dma/dmatest.c +++ b/drivers/dma/dmatest.c @@ -242,6 +242,13 @@ static inline void unmap_dst(struct device *dev, dma_addr_t *addr, size_t len, dma_unmap_single(dev, addr[count], len, DMA_BIDIRECTIONAL); } +static unsigned int min_odd(unsigned int x, unsigned int y) +{ + unsigned int val = min(x, y); + + return val % 2 ? val : val - 1; +} + /* * This function repeatedly tests DMA transfers of various lengths and * offsets for a given operation type until it is told to exit by @@ -262,6 +269,7 @@ static int dmatest_func(void *data) struct dmatest_thread *thread = data; struct dmatest_done done = { .wait = &done_wait }; struct dma_chan *chan; + struct dma_device *dev; const char *thread_name; unsigned int src_off, dst_off, len; unsigned int error_count; @@ -283,13 +291,16 @@ static int dmatest_func(void *data) smp_rmb(); chan = thread->chan; + dev = chan->device; if (thread->type == DMA_MEMCPY) src_cnt = dst_cnt = 1; else if (thread->type == DMA_XOR) { - src_cnt = xor_sources | 1; /* force odd to ensure dst = src */ + /* force odd to ensure dst = src */ + src_cnt = min_odd(xor_sources | 1, dev->max_xor); dst_cnt = 1; } else if (thread->type == DMA_PQ) { - src_cnt = pq_sources | 1; /* force odd to ensure dst = src */ + /* force odd to ensure dst = src */ + src_cnt = min_odd(pq_sources | 1, dma_maxpq(dev, 0)); dst_cnt = 2; for (i = 0; i < src_cnt; i++) pq_coefs[i] = 1; @@ -327,7 +338,6 @@ static int dmatest_func(void *data) while (!kthread_should_stop() && !(iterations && total_tests >= iterations)) { - struct dma_device *dev = chan->device; struct dma_async_tx_descriptor *tx = NULL; dma_addr_t dma_srcs[src_cnt]; dma_addr_t dma_dsts[dst_cnt]; -- GitLab