xref: /linux/drivers/tee/tee_shm_pool.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015, Linaro Limited
4  */
5 #include <linux/device.h>
6 #include <linux/dma-buf.h>
7 #include <linux/genalloc.h>
8 #include <linux/slab.h>
9 #include <linux/tee_drv.h>
10 #include "tee_private.h"
11 
12 static int pool_op_gen_alloc(struct tee_shm_pool_mgr *poolm,
13 			     struct tee_shm *shm, size_t size)
14 {
15 	unsigned long va;
16 	struct gen_pool *genpool = poolm->private_data;
17 	size_t s = roundup(size, 1 << genpool->min_alloc_order);
18 
19 	va = gen_pool_alloc(genpool, s);
20 	if (!va)
21 		return -ENOMEM;
22 
23 	memset((void *)va, 0, s);
24 	shm->kaddr = (void *)va;
25 	shm->paddr = gen_pool_virt_to_phys(genpool, va);
26 	shm->size = s;
27 	return 0;
28 }
29 
30 static void pool_op_gen_free(struct tee_shm_pool_mgr *poolm,
31 			     struct tee_shm *shm)
32 {
33 	gen_pool_free(poolm->private_data, (unsigned long)shm->kaddr,
34 		      shm->size);
35 	shm->kaddr = NULL;
36 }
37 
38 static void pool_op_gen_destroy_poolmgr(struct tee_shm_pool_mgr *poolm)
39 {
40 	gen_pool_destroy(poolm->private_data);
41 	kfree(poolm);
42 }
43 
44 static const struct tee_shm_pool_mgr_ops pool_ops_generic = {
45 	.alloc = pool_op_gen_alloc,
46 	.free = pool_op_gen_free,
47 	.destroy_poolmgr = pool_op_gen_destroy_poolmgr,
48 };
49 
50 /**
51  * tee_shm_pool_alloc_res_mem() - Create a shared memory pool from reserved
52  * memory range
53  * @priv_info:	Information for driver private shared memory pool
54  * @dmabuf_info: Information for dma-buf shared memory pool
55  *
56  * Start and end of pools will must be page aligned.
57  *
58  * Allocation with the flag TEE_SHM_DMA_BUF set will use the range supplied
59  * in @dmabuf, others will use the range provided by @priv.
60  *
61  * @returns pointer to a 'struct tee_shm_pool' or an ERR_PTR on failure.
62  */
63 struct tee_shm_pool *
64 tee_shm_pool_alloc_res_mem(struct tee_shm_pool_mem_info *priv_info,
65 			   struct tee_shm_pool_mem_info *dmabuf_info)
66 {
67 	struct tee_shm_pool_mgr *priv_mgr;
68 	struct tee_shm_pool_mgr *dmabuf_mgr;
69 	void *rc;
70 
71 	/*
72 	 * Create the pool for driver private shared memory
73 	 */
74 	rc = tee_shm_pool_mgr_alloc_res_mem(priv_info->vaddr, priv_info->paddr,
75 					    priv_info->size,
76 					    3 /* 8 byte aligned */);
77 	if (IS_ERR(rc))
78 		return rc;
79 	priv_mgr = rc;
80 
81 	/*
82 	 * Create the pool for dma_buf shared memory
83 	 */
84 	rc = tee_shm_pool_mgr_alloc_res_mem(dmabuf_info->vaddr,
85 					    dmabuf_info->paddr,
86 					    dmabuf_info->size, PAGE_SHIFT);
87 	if (IS_ERR(rc))
88 		goto err_free_priv_mgr;
89 	dmabuf_mgr = rc;
90 
91 	rc = tee_shm_pool_alloc(priv_mgr, dmabuf_mgr);
92 	if (IS_ERR(rc))
93 		goto err_free_dmabuf_mgr;
94 
95 	return rc;
96 
97 err_free_dmabuf_mgr:
98 	tee_shm_pool_mgr_destroy(dmabuf_mgr);
99 err_free_priv_mgr:
100 	tee_shm_pool_mgr_destroy(priv_mgr);
101 
102 	return rc;
103 }
104 EXPORT_SYMBOL_GPL(tee_shm_pool_alloc_res_mem);
105 
106 struct tee_shm_pool_mgr *tee_shm_pool_mgr_alloc_res_mem(unsigned long vaddr,
107 							phys_addr_t paddr,
108 							size_t size,
109 							int min_alloc_order)
110 {
111 	const size_t page_mask = PAGE_SIZE - 1;
112 	struct tee_shm_pool_mgr *mgr;
113 	int rc;
114 
115 	/* Start and end must be page aligned */
116 	if (vaddr & page_mask || paddr & page_mask || size & page_mask)
117 		return ERR_PTR(-EINVAL);
118 
119 	mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
120 	if (!mgr)
121 		return ERR_PTR(-ENOMEM);
122 
123 	mgr->private_data = gen_pool_create(min_alloc_order, -1);
124 	if (!mgr->private_data) {
125 		rc = -ENOMEM;
126 		goto err;
127 	}
128 
129 	gen_pool_set_algo(mgr->private_data, gen_pool_best_fit, NULL);
130 	rc = gen_pool_add_virt(mgr->private_data, vaddr, paddr, size, -1);
131 	if (rc) {
132 		gen_pool_destroy(mgr->private_data);
133 		goto err;
134 	}
135 
136 	mgr->ops = &pool_ops_generic;
137 
138 	return mgr;
139 err:
140 	kfree(mgr);
141 
142 	return ERR_PTR(rc);
143 }
144 EXPORT_SYMBOL_GPL(tee_shm_pool_mgr_alloc_res_mem);
145 
146 static bool check_mgr_ops(struct tee_shm_pool_mgr *mgr)
147 {
148 	return mgr && mgr->ops && mgr->ops->alloc && mgr->ops->free &&
149 		mgr->ops->destroy_poolmgr;
150 }
151 
152 struct tee_shm_pool *tee_shm_pool_alloc(struct tee_shm_pool_mgr *priv_mgr,
153 					struct tee_shm_pool_mgr *dmabuf_mgr)
154 {
155 	struct tee_shm_pool *pool;
156 
157 	if (!check_mgr_ops(priv_mgr) || !check_mgr_ops(dmabuf_mgr))
158 		return ERR_PTR(-EINVAL);
159 
160 	pool = kzalloc(sizeof(*pool), GFP_KERNEL);
161 	if (!pool)
162 		return ERR_PTR(-ENOMEM);
163 
164 	pool->private_mgr = priv_mgr;
165 	pool->dma_buf_mgr = dmabuf_mgr;
166 
167 	return pool;
168 }
169 EXPORT_SYMBOL_GPL(tee_shm_pool_alloc);
170 
171 /**
172  * tee_shm_pool_free() - Free a shared memory pool
173  * @pool:	The shared memory pool to free
174  *
175  * There must be no remaining shared memory allocated from this pool when
176  * this function is called.
177  */
178 void tee_shm_pool_free(struct tee_shm_pool *pool)
179 {
180 	if (pool->private_mgr)
181 		tee_shm_pool_mgr_destroy(pool->private_mgr);
182 	if (pool->dma_buf_mgr)
183 		tee_shm_pool_mgr_destroy(pool->dma_buf_mgr);
184 	kfree(pool);
185 }
186 EXPORT_SYMBOL_GPL(tee_shm_pool_free);
187