dma-pool: make sure atomic pool suits device

void *dma_alloc_from_pool(struct device *dev, size_t size,

			  struct page **ret_page, gfp_t flags)

{

	struct gen_pool *pool = dma_guess_pool(dev, NULL);

	unsigned long val;

	struct gen_pool *pool = NULL;

	unsigned long val = 0;

	void *ptr = NULL;

	phys_addr_t phys;

	while (1) {

		pool = dma_guess_pool(dev, pool);

		if (!pool) {

		WARN(1, "%pGg atomic pool not initialised!\n", &flags);

		return NULL;

			WARN(1, "Failed to get suitable pool for %s\n",

			     dev_name(dev));

			break;

		}

		val = gen_pool_alloc(pool, size);

	if (likely(val)) {

		phys_addr_t phys = gen_pool_virt_to_phys(pool, val);

		if (!val)

			continue;

		phys = gen_pool_virt_to_phys(pool, val);

		if (dma_coherent_ok(dev, phys, size))

			break;

		gen_pool_free(pool, val, size);

		val = 0;

	}

	if (val) {

		*ret_page = pfn_to_page(__phys_to_pfn(phys));

		ptr = (void *)val;

		memset(ptr, 0, size);

	} else {

		WARN_ONCE(1, "DMA coherent pool depleted, increase size "

			     "(recommended min coherent_pool=%zuK)\n",

			  gen_pool_size(pool) >> 9);

	}

		if (gen_pool_avail(pool) < atomic_pool_size)

			schedule_work(&atomic_pool_work);

	}

	return ptr;

}

bool dma_free_from_pool(struct device *dev, void *start, size_t size)

{

	struct gen_pool *pool = dma_guess_pool(dev, NULL);

	struct gen_pool *pool = NULL;

	if (!pool || !gen_pool_has_addr(pool, (unsigned long)start, size))

	while (1) {

		pool = dma_guess_pool(dev, pool);

		if (!pool)

			return false;

		if (gen_pool_has_addr(pool, (unsigned long)start, size)) {

			gen_pool_free(pool, (unsigned long)start, size);

			return true;

		}

	}

}