1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/tee/tee_shm_pool.c b/drivers/tee/tee_shm_pool.c
new file mode 100644
index 000000000..058bfbac6
--- /dev/null
+++ b/drivers/tee/tee_shm_pool.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2015, 2017, 2022 Linaro Limited
+ */
+#include <linux/device.h>
+#include <linux/dma-buf.h>
+#include <linux/genalloc.h>
+#include <linux/slab.h>
+#include <linux/tee_drv.h>
+#include "tee_private.h"
+
+static int pool_op_gen_alloc(struct tee_shm_pool *pool, struct tee_shm *shm,
+			     size_t size, size_t align)
+{
+	unsigned long va;
+	struct gen_pool *genpool = pool->private_data;
+	size_t a = max_t(size_t, align, BIT(genpool->min_alloc_order));
+	struct genpool_data_align data = { .align = a };
+	size_t s = roundup(size, a);
+
+	va = gen_pool_alloc_algo(genpool, s, gen_pool_first_fit_align, &data);
+	if (!va)
+		return -ENOMEM;
+
+	memset((void *)va, 0, s);
+	shm->kaddr = (void *)va;
+	shm->paddr = gen_pool_virt_to_phys(genpool, va);
+	shm->size = s;
+	/*
+	 * This is from a static shared memory pool so no need to register
+	 * each chunk, and no need to unregister later either.
+	 */
+	shm->flags &= ~TEE_SHM_DYNAMIC;
+	return 0;
+}
+
+static void pool_op_gen_free(struct tee_shm_pool *pool, struct tee_shm *shm)
+{
+	gen_pool_free(pool->private_data, (unsigned long)shm->kaddr,
+		      shm->size);
+	shm->kaddr = NULL;
+}
+
+static void pool_op_gen_destroy_pool(struct tee_shm_pool *pool)
+{
+	gen_pool_destroy(pool->private_data);
+	kfree(pool);
+}
+
+static const struct tee_shm_pool_ops pool_ops_generic = {
+	.alloc = pool_op_gen_alloc,
+	.free = pool_op_gen_free,
+	.destroy_pool = pool_op_gen_destroy_pool,
+};
+
+struct tee_shm_pool *tee_shm_pool_alloc_res_mem(unsigned long vaddr,
+						phys_addr_t paddr, size_t size,
+						int min_alloc_order)
+{
+	const size_t page_mask = PAGE_SIZE - 1;
+	struct tee_shm_pool *pool;
+	int rc;
+
+	/* Start and end must be page aligned */
+	if (vaddr & page_mask || paddr & page_mask || size & page_mask)
+		return ERR_PTR(-EINVAL);
+
+	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
+	if (!pool)
+		return ERR_PTR(-ENOMEM);
+
+	pool->private_data = gen_pool_create(min_alloc_order, -1);
+	if (!pool->private_data) {
+		rc = -ENOMEM;
+		goto err;
+	}
+
+	rc = gen_pool_add_virt(pool->private_data, vaddr, paddr, size, -1);
+	if (rc) {
+		gen_pool_destroy(pool->private_data);
+		goto err;
+	}
+
+	pool->ops = &pool_ops_generic;
+
+	return pool;
+err:
+	kfree(pool);
+
+	return ERR_PTR(rc);
+}
+EXPORT_SYMBOL_GPL(tee_shm_pool_alloc_res_mem);