1 /*
2 * Copyright (c) 2019 LK Trusty Authors. All Rights Reserved.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files
6 * (the "Software"), to deal in the Software without restriction,
7 * including without limitation the rights to use, copy, modify, merge,
8 * publish, distribute, sublicense, and/or sell copies of the Software,
9 * and to permit persons to whom the Software is furnished to do so,
10 * subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22 */
23 #pragma once
24
25 #include <assert.h>
26 #include <lk/reflist.h>
27 #include <sys/types.h>
28
29 __BEGIN_CDECLS
30
31 struct vmm_obj;
32
33 /**
34 * struct vmm_obj_ops - Operation on &struct vmm_obj.
35 */
36 struct vmm_obj_ops {
37 /**
38 * @check_flags: Function to check and optionally modify arch_mmu_flags.
39 *
40 * Check if permission @arch_mmu_flags are allowed and add other flags if
41 * needed.
42 *
43 * If @obj is read-only and ARCH_MMU_FLAG_PERM_RO is not set, return
44 * ERR_ACCESS_DENIED.
45 *
46 * If @obj require a specific memory type (e.g.
47 * ARCH_MMU_FLAG_UNCACHED_DEVICE or ARCH_MMU_FLAG_NS), set those flags.
48 *
49 * Return 0 on success, error code to be passed to caller on failure.
50 */
51 int (*check_flags)(struct vmm_obj *obj, uint *arch_mmu_flags);
52 /**
53 * @get_page: Function to get a page address.
54 *
55 * Get single page or physically contiguous region at @offset bytes from
56 * start of @obj.
57 *
58 * Return 0 on success, error code to be passed to caller on failure.
59 */
60 int (*get_page)(struct vmm_obj *obj, size_t offset, paddr_t *paddr,
61 size_t *paddr_size);
62 /**
63 * @destroy: Function to destroy object.
64 *
65 * Called after the last reference to @obj has been released.
66 */
67 void (*destroy)(struct vmm_obj *obj);
68 };
69
70 /**
71 * struct vmm_obj - Object mappable by vmm.
72 * @obj: Reflist object.
73 * @ops: Pointer to &struct vmm_obj_ops.
74 */
75 struct vmm_obj {
76 struct obj obj;
77 struct vmm_obj_ops *ops;
78 };
79
80 /**
81 * vmm_obj_init - Initialize &struct vmm_obj.
82 * @obj: Object to initialise and add reference to.
83 * @ref: Reference to add.
84 * @ops: Pointer to &struct vmm_obj_ops.
85 */
vmm_obj_init(struct vmm_obj * obj,struct obj_ref * ref,struct vmm_obj_ops * ops)86 static inline __ALWAYS_INLINE void vmm_obj_init(struct vmm_obj *obj,
87 struct obj_ref *ref,
88 struct vmm_obj_ops *ops) {
89 DEBUG_ASSERT(ops->check_flags);
90 DEBUG_ASSERT(ops->get_page);
91 DEBUG_ASSERT(ops->destroy);
92 obj->ops = ops;
93 obj_init(&obj->obj, ref);
94 }
95
96 /**
97 * vmm_obj_del_ref - Add a reference to a vmm_obj.
98 * @obj: Object to add reference to.
99 * @ref: Reference to add.
100 */
101 void vmm_obj_add_ref(struct vmm_obj *obj, struct obj_ref *ref);
102
103 /**
104 * vmm_obj_del_ref - Remove reference. Destroy object if no references remain.
105 * @obj: Object to remove reference from.
106 * @ref: Reference to remove.
107 */
108 void vmm_obj_del_ref(struct vmm_obj *obj, struct obj_ref *ref);
109
110 /**
111 * vmm_obj_has_single_ref - Return whether a &struct vmm_obj has a single
112 * reference to it.
113 * @obj: Object to check for single reference.
114 * @ref: Reference to check. Must be a reference to @obj.
115 *
116 * The result from this function may become invalid if references are added or
117 * deleted after this function returns, either by the caller or other threads.
118 */
119 bool vmm_obj_has_only_ref(struct vmm_obj *obj, struct obj_ref *ref);
120
121 __END_CDECLS
122