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(addr: 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(addr: (unsigned long)shm->kaddr, order: get_order(size: shm->size));
46 shm->kaddr = NULL;
47}
48
49static void pool_op_destroy_pool(struct tee_shm_pool *pool)
50{
51 kfree(objp: 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(size: sizeof(*pool), GFP_KERNEL);
63
64 if (!pool)
65 return ERR_PTR(error: -ENOMEM);
66
67 pool->ops = &pool_ops;
68
69 return pool;
70}
71

source code of linux/drivers/tee/amdtee/shm_pool.c