1// SPDX-License-Identifier: MIT
2/*
3 * Copyright 2019 Advanced Micro Devices, Inc.
4 */
5
6#include <linux/slab.h>
7#include <linux/tee_drv.h>
8#include <linux/psp.h>
9#include "amdtee_private.h"
10
11static int pool_op_alloc(struct tee_shm_pool *pool, struct tee_shm *shm,
12			 size_t size, size_t align)
13{
14	unsigned int order = get_order(size);
15	unsigned long va;
16	int rc;
17
18	/*
19	 * Ignore alignment since this is already going to be page aligned
20	 * and there's no need for any larger alignment.
21	 */
22	va = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
23	if (!va)
24		return -ENOMEM;
25
26	shm->kaddr = (void *)va;
27	shm->paddr = __psp_pa((void *)va);
28	shm->size = PAGE_SIZE << order;
29
30	/* Map the allocated memory in to TEE */
31	rc = amdtee_map_shmem(shm);
32	if (rc) {
33		free_pages(va, order);
34		shm->kaddr = NULL;
35		return rc;
36	}
37
38	return 0;
39}
40
41static void pool_op_free(struct tee_shm_pool *pool, struct tee_shm *shm)
42{
43	/* Unmap the shared memory from TEE */
44	amdtee_unmap_shmem(shm);
45	free_pages((unsigned long)shm->kaddr, get_order(shm->size));
46	shm->kaddr = NULL;
47}
48
49static void pool_op_destroy_pool(struct tee_shm_pool *pool)
50{
51	kfree(pool);
52}
53
54static const struct tee_shm_pool_ops pool_ops = {
55	.alloc = pool_op_alloc,
56	.free = pool_op_free,
57	.destroy_pool = pool_op_destroy_pool,
58};
59
60struct tee_shm_pool *amdtee_config_shm(void)
61{
62	struct tee_shm_pool *pool = kzalloc(sizeof(*pool), GFP_KERNEL);
63
64	if (!pool)
65		return ERR_PTR(-ENOMEM);
66
67	pool->ops = &pool_ops;
68
69	return pool;
70}
71