Re: [PATCH V3 3/4] dmaselftest: add memcpy selftest support functions

From: Sinan Kaya
Date: Sun Nov 08 2015 - 21:46:44 EST




On 11/8/2015 12:13 AM, Timur Tabi wrote:
Sinan Kaya wrote:

+static int dma_selftest_sg(struct dma_device *dmadev,
+ struct dma_chan *dma_chanptr, u64 size,
+ unsigned long flags)
+{
+ dma_addr_t src_dma, dest_dma, dest_dma_it;
+ u8 *dest_buf;
+ u32 i, j = 0;
+ dma_cookie_t cookie;
+ struct dma_async_tx_descriptor *tx;
+ int err = 0;
+ int ret;
+ struct sg_table sg_table;
+ struct scatterlist *sg;
+ int nents = 10, count;
+ bool free_channel = 1;

Booleans are either 'true' or 'false'.


OK

+static int dma_selftest_mapsngle(struct device *dev)
+{
+ u32 buf_size = 256;
+ char *src;
+ int ret = -ENOMEM;
+ dma_addr_t dma_src;
+
+ src = kmalloc(buf_size, GFP_KERNEL);
+ if (!src)
+ return -ENOMEM;
+
+ strcpy(src, "hello world");

kstrdup()?

And why kmalloc anyway? Why not leave it on the stack?

char src[] = "hello world";

?

I need to call dma_map_single on this address to convert it to a DMA address. That's why.




--
Sinan Kaya
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
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