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26#include <linux/kernel.h>
27#include <linux/interrupt.h>
28#include <linux/mm.h>
29#include <linux/dma-mapping.h>
30#include <linux/async_tx.h>
31
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40
41struct dma_async_tx_descriptor *
42async_memset(struct page *dest, int val, unsigned int offset, size_t len,
43 struct async_submit_ctl *submit)
44{
45 struct dma_chan *chan = async_tx_find_channel(submit, DMA_MEMSET,
46 &dest, 1, NULL, 0, len);
47 struct dma_device *device = chan ? chan->device : NULL;
48 struct dma_async_tx_descriptor *tx = NULL;
49
50 if (device && is_dma_fill_aligned(device, offset, 0, len)) {
51 dma_addr_t dma_dest;
52 unsigned long dma_prep_flags = 0;
53
54 if (submit->cb_fn)
55 dma_prep_flags |= DMA_PREP_INTERRUPT;
56 if (submit->flags & ASYNC_TX_FENCE)
57 dma_prep_flags |= DMA_PREP_FENCE;
58 dma_dest = dma_map_page(device->dev, dest, offset, len,
59 DMA_FROM_DEVICE);
60
61 tx = device->device_prep_dma_memset(chan, dma_dest, val, len,
62 dma_prep_flags);
63 }
64
65 if (tx) {
66 pr_debug("%s: (async) len: %zu\n", __func__, len);
67 async_tx_submit(chan, tx, submit);
68 } else {
69 void *dest_buf;
70 pr_debug("%s: (sync) len: %zu\n", __func__, len);
71
72 dest_buf = page_address(dest) + offset;
73
74
75 async_tx_quiesce(&submit->depend_tx);
76
77 memset(dest_buf, val, len);
78
79 async_tx_sync_epilog(submit);
80 }
81
82 return tx;
83}
84EXPORT_SYMBOL_GPL(async_memset);
85
86MODULE_AUTHOR("Intel Corporation");
87MODULE_DESCRIPTION("asynchronous memset api");
88MODULE_LICENSE("GPL");
89