1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015, Linaro Limited
4  * Copyright (c) 2017, EPAM Systems
5  */
6 #include <linux/device.h>
7 #include <linux/dma-buf.h>
8 #include <linux/genalloc.h>
9 #include <linux/slab.h>
10 #include <linux/tee_drv.h>
11 #include "optee_private.h"
12 #include "optee_smc.h"
13 #include "shm_pool.h"
14 
pool_op_alloc(struct tee_shm_pool_mgr * poolm,struct tee_shm * shm,size_t size)15 static int pool_op_alloc(struct tee_shm_pool_mgr *poolm,
16 			 struct tee_shm *shm, size_t size)
17 {
18 	unsigned int order = get_order(size);
19 	struct page *page;
20 	int rc = 0;
21 
22 	page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
23 	if (!page)
24 		return -ENOMEM;
25 
26 	shm->kaddr = page_address(page);
27 	shm->paddr = page_to_phys(page);
28 	shm->size = PAGE_SIZE << order;
29 
30 	if (shm->flags & TEE_SHM_DMA_BUF) {
31 		unsigned int nr_pages = 1 << order, i;
32 		struct page **pages;
33 
34 		pages = kcalloc(nr_pages, sizeof(pages), GFP_KERNEL);
35 		if (!pages)
36 			return -ENOMEM;
37 
38 		for (i = 0; i < nr_pages; i++) {
39 			pages[i] = page;
40 			page++;
41 		}
42 
43 		shm->flags |= TEE_SHM_REGISTER;
44 		rc = optee_shm_register(shm->ctx, shm, pages, nr_pages,
45 					(unsigned long)shm->kaddr);
46 		kfree(pages);
47 	}
48 
49 	return rc;
50 }
51 
pool_op_free(struct tee_shm_pool_mgr * poolm,struct tee_shm * shm)52 static void pool_op_free(struct tee_shm_pool_mgr *poolm,
53 			 struct tee_shm *shm)
54 {
55 	if (shm->flags & TEE_SHM_DMA_BUF)
56 		optee_shm_unregister(shm->ctx, shm);
57 
58 	free_pages((unsigned long)shm->kaddr, get_order(shm->size));
59 	shm->kaddr = NULL;
60 }
61 
pool_op_destroy_poolmgr(struct tee_shm_pool_mgr * poolm)62 static void pool_op_destroy_poolmgr(struct tee_shm_pool_mgr *poolm)
63 {
64 	kfree(poolm);
65 }
66 
67 static const struct tee_shm_pool_mgr_ops pool_ops = {
68 	.alloc = pool_op_alloc,
69 	.free = pool_op_free,
70 	.destroy_poolmgr = pool_op_destroy_poolmgr,
71 };
72 
73 /**
74  * optee_shm_pool_alloc_pages() - create page-based allocator pool
75  *
76  * This pool is used when OP-TEE supports dymanic SHM. In this case
77  * command buffers and such are allocated from kernel's own memory.
78  */
optee_shm_pool_alloc_pages(void)79 struct tee_shm_pool_mgr *optee_shm_pool_alloc_pages(void)
80 {
81 	struct tee_shm_pool_mgr *mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
82 
83 	if (!mgr)
84 		return ERR_PTR(-ENOMEM);
85 
86 	mgr->ops = &pool_ops;
87 
88 	return mgr;
89 }
90