1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** USBX Component */
16 /** */
17 /** Storage Class */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22
23 /* Include necessary system files. */
24
25 #define UX_SOURCE_CODE
26
27 #include "ux_api.h"
28 #include "ux_host_class_storage.h"
29 #include "ux_host_stack.h"
30
31
32 /**************************************************************************/
33 /* */
34 /* FUNCTION RELEASE */
35 /* */
36 /* _ux_host_class_storage_partition_read PORTABLE C */
37 /* 6.1.2 */
38 /* AUTHOR */
39 /* */
40 /* Chaoqiong Xiao, Microsoft Corporation */
41 /* */
42 /* DESCRIPTION */
43 /* */
44 /* This function will analyze the partition table and parse all the */
45 /* partitions. It may happen that a partition entry points to a */
46 /* secondary partition table. */
47 /* */
48 /* INPUT */
49 /* */
50 /* storage Pointer to storage class */
51 /* sector_memory Pointer to memory for sector */
52 /* sector Sector number */
53 /* */
54 /* OUTPUT */
55 /* */
56 /* Completion Status */
57 /* */
58 /* CALLS */
59 /* */
60 /* _ux_host_class_storage_media_mount Mount media */
61 /* _ux_host_class_storage_media_open Open media */
62 /* _ux_utility_long_get Get 32-bit word */
63 /* */
64 /* CALLED BY */
65 /* */
66 /* _ux_host_class_storage_media_mount Mount media */
67 /* */
68 /* RELEASE HISTORY */
69 /* */
70 /* DATE NAME DESCRIPTION */
71 /* */
72 /* 05-19-2020 Chaoqiong Xiao Initial Version 6.0 */
73 /* 09-30-2020 Chaoqiong Xiao Modified comment(s), */
74 /* added option to disable FX */
75 /* media integration, */
76 /* resulting in version 6.1 */
77 /* 11-09-2020 Chaoqiong Xiao Modified comment(s), */
78 /* added exFAT support, */
79 /* resulting in version 6.1.2 */
80 /* */
81 /**************************************************************************/
_ux_host_class_storage_partition_read(UX_HOST_CLASS_STORAGE * storage,UCHAR * sector_memory,ULONG sector)82 UINT _ux_host_class_storage_partition_read(UX_HOST_CLASS_STORAGE *storage, UCHAR *sector_memory, ULONG sector)
83 {
84 #if defined(UX_HOST_CLASS_STORAGE_NO_FILEX)
85 UX_PARAMETER_NOT_USED(storage);
86 UX_PARAMETER_NOT_USED(sector_memory);
87 UX_PARAMETER_NOT_USED(sector);
88 return(UX_FUNCTION_NOT_SUPPORTED);
89 #else
90 UINT status = UX_ERROR;
91 UINT partition_index;
92
93
94 /* Point the sector buffer to the first partition entry. */
95 sector_memory += UX_HOST_CLASS_STORAGE_PARTITION_TABLE_START;
96
97 /* There are 4 partitions in a partition table. */
98 for (partition_index = 0; partition_index < 4; partition_index++)
99 {
100
101 /* Check if we recognize this partition entry. */
102 switch(*(sector_memory + UX_HOST_CLASS_STORAGE_PARTITION_TYPE))
103 {
104
105 case UX_HOST_CLASS_STORAGE_PARTITION_FAT_12:
106 case UX_HOST_CLASS_STORAGE_PARTITION_FAT_16:
107 case UX_HOST_CLASS_STORAGE_PARTITION_FAT_16L:
108 case UX_HOST_CLASS_STORAGE_PARTITION_FAT_16_LBA_MAPPED:
109 case UX_HOST_CLASS_STORAGE_PARTITION_FAT_32_1:
110 case UX_HOST_CLASS_STORAGE_PARTITION_FAT_32_2:
111 case UX_HOST_CLASS_STORAGE_PARTITION_EXFAT:
112
113 /* We have found a legal partition entry pointing to a potential boot sector. */
114 status = _ux_host_class_storage_media_open(storage, sector + _ux_utility_long_get(sector_memory + UX_HOST_CLASS_STORAGE_PARTITION_SECTORS_BEFORE));
115 break;
116
117 case UX_HOST_CLASS_STORAGE_PARTITION_EXTENDED:
118 case UX_HOST_CLASS_STORAGE_PARTITION_EXTENDED_LBA_MAPPED:
119
120 /* We have found an entry to an extended partition. We need to read that partition sector
121 and recursively mount all partitions found. */
122 status = _ux_host_class_storage_media_mount(storage, sector + _ux_utility_long_get(sector_memory + UX_HOST_CLASS_STORAGE_PARTITION_SECTORS_BEFORE));
123 break;
124
125 default:
126
127 /* We have found something which is not a DOS recognized partition, or an empty entry.
128 Ignore it and proceed with the rest. */
129 break;
130 }
131
132 /* Move to the next partition entry. */
133 sector_memory += UX_HOST_CLASS_STORAGE_PARTITION_TABLE_SIZE;
134 }
135
136 /* Return completion status. */
137 return(status);
138 #endif
139 }
140
141
