ZYNQMP_DMA_ALLOC_FIXED_SIZE
memzero_explicit(ubuf, ZYNQMP_DMA_ALLOC_FIXED_SIZE);
if (remaining_len >= ZYNQMP_DMA_ALLOC_FIXED_SIZE) {
update_size = ZYNQMP_DMA_ALLOC_FIXED_SIZE;
remaining_len -= ZYNQMP_DMA_ALLOC_FIXED_SIZE;
ubuf = dma_alloc_coherent(dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, &update_dma_addr, GFP_KERNEL);
dma_free_coherent(sha3_drv_ctx.dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, ubuf, update_dma_addr);
dma_free_coherent(sha3_drv_ctx.dev, ZYNQMP_DMA_ALLOC_FIXED_SIZE, ubuf, update_dma_addr);