xref: /OK3568_Linux_fs/u-boot/include/android_avb/avb_ab_ops.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (C) 2016 The Android Open Source Project
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Permission is hereby granted, free of charge, to any person
5*4882a593Smuzhiyun  * obtaining a copy of this software and associated documentation
6*4882a593Smuzhiyun  * files (the "Software"), to deal in the Software without
7*4882a593Smuzhiyun  * restriction, including without limitation the rights to use, copy,
8*4882a593Smuzhiyun  * modify, merge, publish, distribute, sublicense, and/or sell copies
9*4882a593Smuzhiyun  * of the Software, and to permit persons to whom the Software is
10*4882a593Smuzhiyun  * furnished to do so, subject to the following conditions:
11*4882a593Smuzhiyun  *
12*4882a593Smuzhiyun  * The above copyright notice and this permission notice shall be
13*4882a593Smuzhiyun  * included in all copies or substantial portions of the Software.
14*4882a593Smuzhiyun  *
15*4882a593Smuzhiyun  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16*4882a593Smuzhiyun  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17*4882a593Smuzhiyun  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18*4882a593Smuzhiyun  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19*4882a593Smuzhiyun  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20*4882a593Smuzhiyun  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21*4882a593Smuzhiyun  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22*4882a593Smuzhiyun  * SOFTWARE.
23*4882a593Smuzhiyun  */
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun /*
26*4882a593Smuzhiyun #if !defined(AVB_INSIDE_LIBAVB_AB_H) && !defined(AVB_COMPILATION)
27*4882a593Smuzhiyun #error \
28*4882a593Smuzhiyun     "Never include this file directly, include libavb_ab/libavb_ab.h instead."
29*4882a593Smuzhiyun #endif
30*4882a593Smuzhiyun */
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun #ifndef AVB_AB_OPS_H_
33*4882a593Smuzhiyun #define AVB_AB_OPS_H_
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun #include <android_avb/libavb.h>
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun #ifdef __cplusplus
38*4882a593Smuzhiyun extern "C" {
39*4882a593Smuzhiyun #endif
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun struct AvbABOps;
42*4882a593Smuzhiyun typedef struct AvbABOps AvbABOps;
43*4882a593Smuzhiyun 
44*4882a593Smuzhiyun struct AvbABData;
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun /* High-level operations/functions/methods for A/B that are platform
47*4882a593Smuzhiyun  * dependent.
48*4882a593Smuzhiyun  */
49*4882a593Smuzhiyun struct AvbABOps {
50*4882a593Smuzhiyun   /* Operations from libavb. */
51*4882a593Smuzhiyun   AvbOps* ops;
52*4882a593Smuzhiyun 
53*4882a593Smuzhiyun   /* Reads A/B metadata from persistent storage. Returned data is
54*4882a593Smuzhiyun    * properly byteswapped. Returns AVB_IO_RESULT_OK on success, error
55*4882a593Smuzhiyun    * code otherwise.
56*4882a593Smuzhiyun    *
57*4882a593Smuzhiyun    * If the data read is invalid (e.g. wrong magic or CRC checksum
58*4882a593Smuzhiyun    * failure), the metadata shoule be reset using avb_ab_data_init()
59*4882a593Smuzhiyun    * and then written to persistent storage.
60*4882a593Smuzhiyun    *
61*4882a593Smuzhiyun    * Implementations will typically want to use avb_ab_data_read()
62*4882a593Smuzhiyun    * here to use the 'misc' partition for persistent storage.
63*4882a593Smuzhiyun    */
64*4882a593Smuzhiyun   AvbIOResult (*read_ab_metadata)(AvbABOps* ab_ops, struct AvbABData* data);
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun   /* Writes A/B metadata to persistent storage. This will byteswap and
67*4882a593Smuzhiyun    * update the CRC as needed. Returns AVB_IO_RESULT_OK on success,
68*4882a593Smuzhiyun    * error code otherwise.
69*4882a593Smuzhiyun    *
70*4882a593Smuzhiyun    * Implementations will typically want to use avb_ab_data_write()
71*4882a593Smuzhiyun    * here to use the 'misc' partition for persistent storage.
72*4882a593Smuzhiyun    */
73*4882a593Smuzhiyun   AvbIOResult (*write_ab_metadata)(AvbABOps* ab_ops,
74*4882a593Smuzhiyun                                    const struct AvbABData* data);
75*4882a593Smuzhiyun };
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun #ifdef __cplusplus
78*4882a593Smuzhiyun }
79*4882a593Smuzhiyun #endif
80*4882a593Smuzhiyun 
81*4882a593Smuzhiyun #endif /* AVB_AB_OPS_H_ */
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