1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. 4 */ 5 6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 7 8 #include <linux/firmware/qcom/qcom_tzmem.h> 9 #include <linux/mm.h> 10 11 #include "qcomtee.h" 12 13 /** 14 * define MAX_OUTBOUND_BUFFER_SIZE - Maximum size of outbound buffers. 15 * 16 * The size of outbound buffer depends on QTEE callback requests. 17 */ 18 #define MAX_OUTBOUND_BUFFER_SIZE SZ_4K 19 20 /** 21 * define MAX_INBOUND_BUFFER_SIZE - Maximum size of the inbound buffer. 22 * 23 * The size of the inbound buffer depends on the user's requests, 24 * specifically the number of IB and OB arguments. If an invocation 25 * requires a size larger than %MAX_INBOUND_BUFFER_SIZE, the user should 26 * consider using another form of shared memory with QTEE. 27 */ 28 #define MAX_INBOUND_BUFFER_SIZE SZ_4M 29 30 /** 31 * qcomtee_msg_buffers_alloc() - Allocate inbound and outbound buffers. 32 * @oic: context to use for the current invocation. 33 * @u: array of arguments for the current invocation. 34 * 35 * It calculates the size of inbound and outbound buffers based on the 36 * arguments in @u. It allocates the buffers from the teedev pool. 37 * 38 * Return: On success, returns 0. On error, returns < 0. 39 */ 40 int qcomtee_msg_buffers_alloc(struct qcomtee_object_invoke_ctx *oic, 41 struct qcomtee_arg *u) 42 { 43 struct tee_context *ctx = oic->ctx; 44 struct tee_shm *shm; 45 size_t size; 46 int i; 47 48 /* Start offset in a message for buffer arguments. */ 49 size = qcomtee_msg_buffer_args(struct qcomtee_msg_object_invoke, 50 qcomtee_args_len(u)); 51 if (size > MAX_INBOUND_BUFFER_SIZE) 52 return -EINVAL; 53 54 /* Add size of IB arguments. */ 55 qcomtee_arg_for_each_input_buffer(i, u) { 56 size = size_add(size, qcomtee_msg_offset_align(u[i].b.size)); 57 if (size > MAX_INBOUND_BUFFER_SIZE) 58 return -EINVAL; 59 } 60 61 /* Add size of OB arguments. */ 62 qcomtee_arg_for_each_output_buffer(i, u) { 63 size = size_add(size, qcomtee_msg_offset_align(u[i].b.size)); 64 if (size > MAX_INBOUND_BUFFER_SIZE) 65 return -EINVAL; 66 } 67 68 shm = tee_shm_alloc_priv_buf(ctx, size); 69 if (IS_ERR(shm)) 70 return PTR_ERR(shm); 71 72 /* Allocate inbound buffer. */ 73 oic->in_shm = shm; 74 shm = tee_shm_alloc_priv_buf(ctx, MAX_OUTBOUND_BUFFER_SIZE); 75 if (IS_ERR(shm)) { 76 tee_shm_free(oic->in_shm); 77 78 return PTR_ERR(shm); 79 } 80 /* Allocate outbound buffer. */ 81 oic->out_shm = shm; 82 83 oic->in_msg.addr = tee_shm_get_va(oic->in_shm, 0); 84 oic->in_msg.size = tee_shm_get_size(oic->in_shm); 85 oic->out_msg.addr = tee_shm_get_va(oic->out_shm, 0); 86 oic->out_msg.size = tee_shm_get_size(oic->out_shm); 87 /* QTEE assume unused buffers are zeroed. */ 88 memzero_explicit(oic->in_msg.addr, oic->in_msg.size); 89 memzero_explicit(oic->out_msg.addr, oic->out_msg.size); 90 91 return 0; 92 } 93 94 void qcomtee_msg_buffers_free(struct qcomtee_object_invoke_ctx *oic) 95 { 96 tee_shm_free(oic->in_shm); 97 tee_shm_free(oic->out_shm); 98 } 99 100 /* Dynamic shared memory pool based on tee_dyn_shm_alloc_helper(). */ 101 102 static int qcomtee_shm_register(struct tee_context *ctx, struct tee_shm *shm, 103 struct page **pages, size_t num_pages, 104 unsigned long start) 105 { 106 return qcom_tzmem_shm_bridge_create(shm->paddr, shm->size, 107 &shm->sec_world_id); 108 } 109 110 static int qcomtee_shm_unregister(struct tee_context *ctx, struct tee_shm *shm) 111 { 112 qcom_tzmem_shm_bridge_delete(shm->sec_world_id); 113 114 return 0; 115 } 116 117 static int pool_op_alloc(struct tee_shm_pool *pool, struct tee_shm *shm, 118 size_t size, size_t align) 119 { 120 return tee_dyn_shm_alloc_helper(shm, size, align, qcomtee_shm_register); 121 } 122 123 static void pool_op_free(struct tee_shm_pool *pool, struct tee_shm *shm) 124 { 125 tee_dyn_shm_free_helper(shm, qcomtee_shm_unregister); 126 } 127 128 static void pool_op_destroy_pool(struct tee_shm_pool *pool) 129 { 130 kfree(pool); 131 } 132 133 static const struct tee_shm_pool_ops pool_ops = { 134 .alloc = pool_op_alloc, 135 .free = pool_op_free, 136 .destroy_pool = pool_op_destroy_pool, 137 }; 138 139 struct tee_shm_pool *qcomtee_shm_pool_alloc(void) 140 { 141 struct tee_shm_pool *pool; 142 143 pool = kzalloc(sizeof(*pool), GFP_KERNEL); 144 if (!pool) 145 return ERR_PTR(-ENOMEM); 146 147 pool->ops = &pool_ops; 148 149 return pool; 150 } 151