Vishal Bhoj | 82c8071 | 2015-12-15 21:13:33 +0530 | [diff] [blame^] | 1 | /*
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| 2 | * Copyright (c) 1999, 2000
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| 3 | * Intel Corporation.
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| 4 | * All rights reserved.
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| 5 | * Copyright (c) Huawei Technologies Co., Ltd. 2013. All rights reserved.
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| 6 | *
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| 7 | * Redistribution and use in source and binary forms, with or without modification,
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| 8 | * are permitted provided that the following conditions are met:
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| 9 | *
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| 10 | * 1. Redistributions of source code must retain the above copyright notice,
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| 11 | * this list of conditions and the following disclaimer.
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| 12 | *
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| 13 | * 2. Redistributions in binary form must reproduce the above copyright notice,
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| 14 | * this list of conditions and the following disclaimer in the documentation
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| 15 | * and/or other materials provided with the distribution.
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| 16 | *
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| 17 | * 3. All advertising materials mentioning features or use of this software must
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| 18 | * display the following acknowledgement:
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| 19 | *
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| 20 | * This product includes software developed by Intel Corporation and its
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| 21 | * contributors.
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| 22 | *
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| 23 | * 4. Neither the name of Intel Corporation or its contributors may be used to
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| 24 | * endorse or promote products derived from this software without specific
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| 25 | * prior written permission.
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| 26 | *
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| 27 | * THIS SOFTWARE IS PROVIDED BY INTEL CORPORATION AND CONTRIBUTORS ``AS IS'' AND
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| 28 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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| 29 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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| 30 | * DISCLAIMED. IN NO EVENT SHALL INTEL CORPORATION OR CONTRIBUTORS BE LIABLE FOR
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| 31 | * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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| 32 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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| 33 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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| 34 | * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| 35 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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| 36 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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| 37 | *
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| 38 | */
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| 39 | #include <Uefi.h>
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| 40 |
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| 41 | #include <Protocol/BlockIo.h>
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| 42 | #include <Protocol/LoadedImage.h>
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| 43 | #include <Library/DebugLib.h>
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| 44 | #include <Library/BaseMemoryLib.h>
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| 45 | #include <Library/UefiDriverEntryPoint.h>
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| 46 | #include <Library/UefiBootServicesTableLib.h>
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| 47 | #include <Library/UefiLib.h>
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| 48 | #include <Library/BaseLib.h>
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| 49 | #include <Library/MemoryAllocationLib.h>
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| 50 |
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| 51 | #include <Library/DevicePathLib.h>
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| 52 | #include "./ramdisk.h"
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| 53 |
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| 54 | #define DEFAULT_DISK_SIZE 30 /* in MBs */
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| 55 |
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| 56 | UINT32 GetDiskSize( EFI_HANDLE ImageHandle );
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| 57 |
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| 58 | /* Embedded version string for VERS utility */
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| 59 | //static char v[] = "version_number=1.00 ";
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| 60 |
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| 61 | /* EFI device path definition */
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| 62 | static RAM_DISK_DEVICE_PATH RamDiskDevicePath =
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| 63 | {
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| 64 | { |
| 65 | MESSAGING_DEVICE_PATH, |
| 66 | MSG_VENDOR_DP, |
| 67 | { |
| 68 | sizeof(RAM_DISK_DEVICE_PATH) - END_DEVICE_PATH_LENGTH, |
| 69 | 0 |
| 70 | }, |
| 71 | }, |
| 72 | // {06ED4DD0-FF78-11d3-BDC4-00A0C94053D1}
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| 73 | { |
| 74 | 0x6ed4dd0, 0xff78, 0x11d3, |
| 75 | {0xbd, 0xc4, 0x0, 0xa0, 0xc9, 0x40, 0x53, 0xd1}, |
| 76 | }, |
| 77 | {0,0,0,0,0,0,0,0}, // ID assigned below |
| 78 | { |
| 79 | END_DEVICE_PATH_TYPE, |
| 80 | END_ENTIRE_DEVICE_PATH_SUBTYPE, |
| 81 | { |
| 82 | END_DEVICE_PATH_LENGTH, |
| 83 | 0 |
| 84 | }, |
| 85 | }, |
| 86 | };
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| 87 |
|
| 88 | /* Lookup table of total sectors vs. cluster size.
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| 89 | * Ramdisk sizes between 0x20D0 (4.1MB) and 0x100000 (512MB) sectors are valid FAT16 drive sizes.
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| 90 | */
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| 91 | /* #define MIN_DISK_SIZE 5 */
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| 92 | #define MIN_DISK_SIZE 1
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| 93 | #define MAX_DISK_SIZE 512
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| 94 | static FAT16TABLE fat16tbl[] =
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| 95 | {
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| 96 | /* {0x000020D0, 0}, */
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| 97 | {0x00000800, 1}, /* 800 sectors * 1 sec/cluster * 512 bytes = 1 M */
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| 98 | {0x00001000, 1}, /* 1000 sectors * 1 sec/cluster * 512 bytes = 2 M */
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| 99 | {0x00001800, 1}, /* 1800 sectors * 1 sec/cluster * 512 bytes = 3 M */
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| 100 | {0x00007FA8, 2},
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| 101 | {0x00040000, 4},
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| 102 | {0x00080000, 8},
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| 103 | {0x00100000,16},
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| 104 | {0xFFFFFFFF, 0}
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| 105 | };
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| 106 |
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| 107 | VOID CopyBOOTSEC(VOID* Start,BOOTSEC* bsc)
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| 108 | {
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| 109 | UINT32 index=0;
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| 110 | UINT8* pStart=(UINT8*)Start;
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| 111 |
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| 112 | CopyMem(&(pStart[index]), &(bsc->BS_jmpBoot[0]), sizeof(bsc->BS_jmpBoot));
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| 113 | index+=sizeof(bsc->BS_jmpBoot);
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| 114 |
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| 115 | CopyMem(&(pStart[index]), &(bsc->BS_OEMName[0]), sizeof(bsc->BS_OEMName));
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| 116 | index+=sizeof(bsc->BS_OEMName);
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| 117 |
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| 118 | CopyMem(&(pStart[index]), &(bsc->BPB_BytsPerSec), sizeof(bsc->BPB_BytsPerSec));
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| 119 | index+=sizeof(bsc->BPB_BytsPerSec);
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| 120 |
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| 121 | CopyMem(&(pStart[index]), &(bsc->BPB_SecPerClus), sizeof(bsc->BPB_SecPerClus));
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| 122 | index+=sizeof(bsc->BPB_SecPerClus);
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| 123 |
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| 124 | CopyMem(&(pStart[index]), &(bsc->BPB_RsvdSecCnt), sizeof(bsc->BPB_RsvdSecCnt));
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| 125 | index+=sizeof(bsc->BPB_RsvdSecCnt);
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| 126 |
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| 127 | CopyMem(&(pStart[index]), &(bsc->BPB_NumFATs), sizeof(bsc->BPB_NumFATs));
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| 128 | index+=sizeof(bsc->BPB_NumFATs);
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| 129 |
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| 130 | CopyMem(&(pStart[index]), &(bsc->BPB_NumFATs), sizeof(bsc->BPB_NumFATs));
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| 131 | index+=sizeof(bsc->BPB_NumFATs);
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| 132 |
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| 133 | CopyMem(&(pStart[index]), &(bsc->BPB_RootEntCnt), sizeof(bsc->BPB_RootEntCnt));
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| 134 | index+=sizeof(bsc->BPB_RootEntCnt);
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| 135 |
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| 136 | CopyMem(&(pStart[index]), &(bsc->BPB_TotSec16), sizeof(bsc->BPB_TotSec16));
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| 137 | index+=sizeof(bsc->BPB_TotSec16);
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| 138 |
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| 139 | CopyMem(&(pStart[index]), &(bsc->BPB_Media), sizeof(bsc->BPB_Media));
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| 140 | index+=sizeof(bsc->BPB_Media);
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| 141 |
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| 142 | CopyMem(&(pStart[index]), &(bsc->BPB_FATSz16), sizeof(bsc->BPB_FATSz16));
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| 143 | index+=sizeof(bsc->BPB_FATSz16);
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| 144 |
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| 145 | CopyMem(&(pStart[index]), &(bsc->BPB_SecPerTrk), sizeof(bsc->BPB_SecPerTrk));
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| 146 | index+=sizeof(bsc->BPB_SecPerTrk);
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| 147 |
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| 148 | CopyMem(&(pStart[index]), &(bsc->BPB_NumHeads), sizeof(bsc->BPB_NumHeads));
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| 149 | index+=sizeof(bsc->BPB_NumHeads);
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| 150 |
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| 151 | CopyMem(&(pStart[index]), &(bsc->BPB_HiddSec), sizeof(bsc->BPB_HiddSec));
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| 152 | index+=sizeof(bsc->BPB_HiddSec);
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| 153 |
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| 154 | CopyMem(&(pStart[index]), &(bsc->BPB_TotSec32), sizeof(bsc->BPB_TotSec32));
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| 155 | index+=sizeof(bsc->BPB_TotSec32);
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| 156 |
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| 157 | CopyMem(&(pStart[index]), &(bsc->BS_DrvNum), sizeof(bsc->BS_DrvNum));
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| 158 | index+=sizeof(bsc->BS_DrvNum);
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| 159 |
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| 160 | CopyMem(&(pStart[index]), &(bsc->BS_Reserved1), sizeof(bsc->BS_Reserved1));
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| 161 | index+=sizeof(bsc->BS_Reserved1);
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| 162 |
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| 163 | CopyMem(&(pStart[index]), &(bsc->BS_BootSig), sizeof(bsc->BS_BootSig));
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| 164 | index+=sizeof(bsc->BS_BootSig);
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| 165 |
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| 166 | CopyMem(&(pStart[index]), &(bsc->BS_VolID), sizeof(bsc->BS_VolID));
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| 167 | index+=sizeof(bsc->BS_VolID);
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| 168 |
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| 169 | CopyMem(&(pStart[index]), &(bsc->BS_VolLab[0]), sizeof(bsc->BS_VolLab));
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| 170 | index+=sizeof(bsc->BS_VolLab);
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| 171 |
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| 172 | CopyMem(&(pStart[index]), &(bsc->BS_FilSysType[0]), sizeof(bsc->BS_FilSysType));
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| 173 | index+=sizeof(bsc->BS_FilSysType);
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| 174 |
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| 175 | CopyMem(&(pStart[index]), &(bsc->BS_Code[0]), sizeof(bsc->BS_Code));
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| 176 | index+=sizeof(bsc->BS_Code);
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| 177 |
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| 178 | CopyMem(&(pStart[index]), &(bsc->BS_Sig), sizeof(bsc->BS_Sig));
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| 179 |
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| 180 | }
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| 181 |
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| 182 | /*++
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| 183 |
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| 184 | Routine Description:
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| 185 |
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| 186 | Convert hex string to uint
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| 187 |
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| 188 | Arguments:
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| 189 |
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| 190 | Str - The string
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| 191 |
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| 192 | Returns:
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| 193 |
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| 194 | --*/
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| 195 | STATIC UINTN Atoi ( CHAR16 *str)
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| 196 | {
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| 197 | UINTN u;
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| 198 | CHAR16 c;
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| 199 | UINTN m;
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| 200 | UINTN n;
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| 201 |
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| 202 | ASSERT (str != NULL);
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| 203 |
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| 204 | m = (UINTN) -1 / 10;
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| 205 | n = (UINTN) -1 % 10;
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| 206 | //
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| 207 | // skip preceeding white space
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| 208 | //
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| 209 | while (*str && (*str == ' '))
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| 210 | {
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| 211 | str += 1;
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| 212 | }
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| 213 | //
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| 214 | // convert digits
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| 215 | //
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| 216 | u = 0;
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| 217 | c = *(str++);
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| 218 | while (c)
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| 219 | {
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| 220 | if ((c >= '0') && (c <= '9'))
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| 221 | {
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| 222 | if ((u >= m) && ((c - '0') > (INTN) n))
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| 223 | {
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| 224 | return (UINTN) -1;
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| 225 | }
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| 226 |
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| 227 | u = (u * 10) + c - '0';
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| 228 | }
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| 229 | else
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| 230 | {
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| 231 | break;
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| 232 | }
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| 233 |
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| 234 | c = *(str++);
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| 235 | }
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| 236 |
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| 237 | return u;
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| 238 | }
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| 239 |
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| 240 | /* Helper function to compute cluster size
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| 241 | * vs. total sectors on drive.
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| 242 | */
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| 243 | STATIC UINT8 size2spc(UINT32 ts)
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| 244 | {
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| 245 | int i = 0;
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| 246 |
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| 247 | while(fat16tbl[i].size != 0xFFFFFFFF)
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| 248 | {
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| 249 | if(ts <= fat16tbl[i].size)
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| 250 | return fat16tbl[i].spc;
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| 251 | ++i;
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| 252 | }
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| 253 |
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| 254 | return 0;
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| 255 | }
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| 256 |
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| 257 | UINT8 TestSize(UINT32 ts)
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| 258 | {
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| 259 | int i = 0;
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| 260 |
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| 261 | while(fat16tbl[i].size != 0xFFFFFFFF)
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| 262 | {
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| 263 | if(ts <= fat16tbl[i].size)
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| 264 | return fat16tbl[i].spc;
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| 265 | ++i;
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| 266 | }
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| 267 |
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| 268 | return 0;
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| 269 | }
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| 270 |
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| 271 | EFI_SYSTEM_TABLE BackupSystemTable;
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| 272 |
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| 273 | /*
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| 274 | * Entry point for RamDisk driver.
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| 275 | */
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| 276 |
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| 277 | EFI_STATUS InitializeRamDiskDriver(
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| 278 | IN EFI_HANDLE ImageHandle,
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| 279 | IN EFI_SYSTEM_TABLE *SystemTable)
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| 280 | {
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| 281 | EFI_STATUS Status;
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| 282 | RAM_DISK_DEV *RamDiskDev;
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| 283 | UINT32 RamDiskSize;
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| 284 | UINT32 NumPages;
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| 285 | UINT32 BlockSize;
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| 286 | UINT64 DiskId;
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| 287 |
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| 288 | /*
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| 289 | * Make a copy of the system table to workaround load command bug
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| 290 | */
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| 291 | CopyMem(&BackupSystemTable,SystemTable,sizeof(BackupSystemTable));
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| 292 |
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| 293 | /*
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| 294 | * Initialize EFI library
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| 295 | */
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| 296 | //InitializeLib(ImageHandle,&BackupSystemTable);
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| 297 |
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| 298 | /* IA64 compiler is removing version string (unused?) so I use it */
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| 299 | //v[0] = 'v';
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| 300 |
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| 301 | /*
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| 302 | * Set the disk size
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| 303 | */
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| 304 | RamDiskSize = GetDiskSize(ImageHandle);
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| 305 | BlockSize = 512;
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| 306 |
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| 307 | /* Allocate storage for ramdisk device info on the heap.
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| 308 | */
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| 309 | RamDiskDev = AllocateZeroPool(sizeof(RAM_DISK_DEV));
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| 310 | if(RamDiskDev == NULL)
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| 311 | return EFI_OUT_OF_RESOURCES;
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| 312 |
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| 313 | /*
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| 314 | * Compute the number of 4KB pages needed by the ramdisk and allocate the memory.
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| 315 | */
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| 316 | NumPages = RamDiskSize / EFI_PAGE_SIZE;
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| 317 | if(NumPages % RamDiskSize)
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| 318 | NumPages++;
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| 319 |
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| 320 | Status = gBS->AllocatePages(AllocateAnyPages,EfiBootServicesData,NumPages,&RamDiskDev->Start);
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| 321 | if(EFI_ERROR(Status)) {
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| 322 | FreePool(RamDiskDev);
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| 323 | return Status;
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| 324 | }
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| 325 |
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| 326 | /*
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| 327 | * Initialize the ramdisk's device info.
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| 328 | */
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| 329 | (void)gBS->GetNextMonotonicCount(&DiskId);
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| 330 | CopyMem(&RamDiskDevicePath.DiskId, &DiskId, sizeof(DiskId));
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| 331 |
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| 332 | RamDiskDev->Signature = PBLOCK_DEVICE_SIGNATURE;
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| 333 | RamDiskDev->BlkIo.Revision = EFI_BLOCK_IO_INTERFACE_REVISION;
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| 334 | RamDiskDev->BlkIo.Media = &RamDiskDev->Media;
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| 335 | RamDiskDev->Media.RemovableMedia = FALSE;
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| 336 | RamDiskDev->Media.MediaPresent = TRUE;
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| 337 |
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| 338 | RamDiskDev->Media.LastBlock = RamDiskSize/BlockSize - 1;
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| 339 | RamDiskDev->Media.BlockSize = BlockSize;
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| 340 | RamDiskDev->Media.LogicalPartition = TRUE;
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| 341 | RamDiskDev->Media.ReadOnly = FALSE;
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| 342 | RamDiskDev->Media.WriteCaching = TRUE;
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| 343 |
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| 344 | RamDiskDev->BlkIo.ReadBlocks = RamDiskReadBlocks;
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| 345 | RamDiskDev->BlkIo.WriteBlocks = RamDiskWriteBlocks;
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| 346 | RamDiskDev->BlkIo.FlushBlocks = RamDiskFlushBlocks;
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| 347 |
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| 348 | RamDiskDev->DevicePath = DuplicateDevicePath((EFI_DEVICE_PATH*)&RamDiskDevicePath);
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| 349 |
|
| 350 | /*
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| 351 | * Build a FAT16 file system on the ramdisk.
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| 352 | */
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| 353 | FormatRamdisk((VOID*)(UINTN)RamDiskDev->Start,RamDiskSize);
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| 354 |
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| 355 | /*
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| 356 | * Install the device.
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| 357 | */
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| 358 |
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| 359 | Status = gBS->InstallMultipleProtocolInterfaces(
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| 360 | &ImageHandle,
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| 361 | &gEfiBlockIoProtocolGuid,
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| 362 | &RamDiskDev->BlkIo,
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| 363 | &gEfiDevicePathProtocolGuid,
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| 364 | RamDiskDev->DevicePath,
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| 365 | NULL);
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| 366 |
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| 367 | DEBUG((EFI_D_ERROR,"ramdisk:blckio install. Status=%r\n",Status));
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| 368 | return Status;
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| 369 | }
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| 370 |
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| 371 | UINT32
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| 372 | GetDiskSize( EFI_HANDLE ImageHandle )
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| 373 | {
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| 374 | EFI_STATUS Status;
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| 375 | EFI_LOADED_IMAGE *Image;
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| 376 | UINT32 DiskSize = DEFAULT_DISK_SIZE;
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| 377 |
|
| 378 | /*
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| 379 | * Check load options to see if they want to specify disk size in MBs
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| 380 | */
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| 381 | Status = gBS->HandleProtocol(ImageHandle, &gEfiLoadedImageProtocolGuid, (void**)&Image);
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| 382 | if (!EFI_ERROR(Status)) {
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| 383 | if (Image->LoadOptions && Image->LoadOptionsSize) {
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| 384 | #define MAX_ARG_SIZE 32
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| 385 | CHAR16 Size[ MAX_ARG_SIZE ];
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| 386 | CHAR16 *CmdLine = Image->LoadOptions;
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| 387 | INT32 CmdLen = (INT32)Image->LoadOptionsSize;
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| 388 |
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| 389 | /*
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| 390 | * Get past program name
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| 391 | */
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| 392 | while( CmdLen > 0 && *CmdLine != L' ' ) {
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| 393 | CmdLen -= sizeof(CHAR16);
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| 394 | CmdLine++;
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| 395 | }
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| 396 |
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| 397 | if ( CmdLen > 0 ) {
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| 398 | /*
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| 399 | * Make sure we're null terminated
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| 400 | */
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| 401 | CopyMem( Size, CmdLine, MIN(CmdLen, sizeof(Size)));
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| 402 | Size[MAX_ARG_SIZE - 1] = 0;
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| 403 |
|
| 404 | /*
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| 405 | * Atoi() will skip any leading white space
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| 406 | */
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| 407 | DiskSize = (UINT32)Atoi(Size);
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| 408 | if (DiskSize == 0)
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| 409 | DiskSize = DEFAULT_DISK_SIZE;
|
| 410 | DiskSize = MAX(DiskSize, MIN_DISK_SIZE);
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| 411 | DiskSize = MIN(DiskSize, MAX_DISK_SIZE);
|
| 412 | }
|
| 413 | }
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| 414 | }
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| 415 |
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| 416 | return (DiskSize * 1024 * 1024);
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| 417 | }
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| 418 |
|
| 419 | /* Given a block of memory representing a ramdisk, build a pseudo-boot sector
|
| 420 | * and initialize the drive.
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| 421 | *
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| 422 | * Assumes the global boot sector structure g_bs has been filled out with the
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| 423 | * static information the boot sector requires. Also assumes the ramdisk size
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| 424 | * is between 4.1MB and 512MB as appropriate for FAT16 file system.
|
| 425 | */
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| 426 | STATIC VOID FormatRamdisk(
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| 427 | IN VOID* pStart,
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| 428 | IN UINT32 Size)
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| 429 | {
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| 430 | UINT32 TotalSectors,RootDirSectors,FatSz,tmp1,tmp2;
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| 431 | UINT8 *Fat1,*Fat2;
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| 432 | BOOTSEC g_bs={
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| 433 | /* BS_jmpBoot */ {0xeb,0x0,0x90},
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| 434 | /* BS_OEMName */ {'E','F','I','R','D','I','S','K'},
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| 435 | /* BPB_BytsPerSec */ 512,
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| 436 | /* BPB_SecPerClus */ 0,
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| 437 | /* BPB_RsvdSecCnt */ 1,
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| 438 | /* BPB_NumFATs */ 2,
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| 439 | /* BPB_RootEntCnt */ 512,
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| 440 | /* BPB_TotSec16 */ 0,
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| 441 | /* BPB_Media */ 0xF8,
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| 442 | /* BPB_FATSz16 */ 0,
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| 443 | /* BPB_SecPerTrk */ 0,
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| 444 | /* BPB_NumHeads */ 0,
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| 445 | /* BPB_HiddSec */ 0,
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| 446 | /* BPB_TotSec32 */ 0,
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| 447 | /* BS_DrvNum */ 0,
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| 448 | /* BS_Reserved1 */ 0,
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| 449 | /* BS_BootSig */ 0x29,
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| 450 | /* BS_VolID */ 0,
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| 451 | /* BS_VolLab */ {'N','O',' ','N','A','M','E',' ',' ',' '},
|
| 452 | /* BS_FilSysType */ {'F','A','T','1','6',' ',' ',' '}
|
| 453 | };
|
| 454 |
|
| 455 | /* The boot signature needs to be filled out */
|
| 456 | g_bs.BS_Sig = 0xAA55;
|
| 457 |
|
| 458 | /* Compute the total sectors and appropriate cluster size */
|
| 459 | TotalSectors = Size / g_bs.BPB_BytsPerSec;
|
| 460 | g_bs.BPB_SecPerClus = size2spc(TotalSectors);
|
| 461 | ASSERT(g_bs.BPB_SecPerClus != 0);
|
| 462 |
|
| 463 | /* Compute how many root directory sectors are needed */
|
| 464 | RootDirSectors = (g_bs.BPB_RootEntCnt * 32 + g_bs.BPB_BytsPerSec - 1) / g_bs.BPB_BytsPerSec;
|
| 465 |
|
| 466 | /* Compute how many sectors are required per FAT */
|
| 467 | tmp1 = TotalSectors - (g_bs.BPB_RsvdSecCnt + RootDirSectors);
|
| 468 | tmp2 = 256 * g_bs.BPB_SecPerClus + g_bs.BPB_NumFATs;
|
| 469 | FatSz = (tmp1 + tmp2 - 1) / tmp2;
|
| 470 | ASSERT(FatSz <= 0xFFFF);
|
| 471 |
|
| 472 | /* Store the total sectors and fat size values */
|
| 473 | if(TotalSectors > 0xFFFF)
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| 474 | g_bs.BPB_TotSec32 = TotalSectors;
|
| 475 | else
|
| 476 | g_bs.BPB_TotSec16 = (UINT16)TotalSectors;
|
| 477 |
|
| 478 | g_bs.BPB_FATSz16 = (UINT16)FatSz;
|
| 479 |
|
| 480 | /* The FAT table and root directory need to be all zeroes.
|
| 481 | * We'll zero the whole drive.
|
| 482 | */
|
| 483 | ZeroMem(pStart,Size);
|
| 484 |
|
| 485 | /* Write the completed boot sector to the ramdisk */
|
| 486 | CopyMem(pStart,&g_bs,512);
|
| 487 |
|
| 488 | /* Compute the starting offsets of the two FATs */
|
| 489 | Fat1 = (UINT8*)pStart + g_bs.BPB_RsvdSecCnt * 512;
|
| 490 | Fat2 = (UINT8*)pStart + (g_bs.BPB_RsvdSecCnt + FatSz) * 512;
|
| 491 |
|
| 492 | /* Initialize FAT1 */
|
| 493 | Fat1[0] = g_bs.BPB_Media;
|
| 494 | Fat1[1] = 0xFF;
|
| 495 | Fat1[2] = 0xFF;
|
| 496 | Fat1[3] = 0xFF;
|
| 497 |
|
| 498 | /* Initialize FAT2 */
|
| 499 | Fat2[0] = g_bs.BPB_Media;
|
| 500 | Fat2[1] = 0xFF;
|
| 501 | Fat2[2] = 0xFF;
|
| 502 | Fat2[3] = 0xFF;
|
| 503 | }
|
| 504 |
|
| 505 | /* Implementation of block I/O read */
|
| 506 | STATIC EFI_STATUS RamDiskReadBlocks(
|
| 507 | IN EFI_BLOCK_IO *This,
|
| 508 | IN UINT32 MediaId,
|
| 509 | IN EFI_LBA LBA,
|
| 510 | IN UINTN BufferSize,
|
| 511 | OUT VOID *Buffer)
|
| 512 | {
|
| 513 | EFI_BLOCK_IO_MEDIA *Media;
|
| 514 | RAM_DISK_DEV *RamDiskDev;
|
| 515 | EFI_PHYSICAL_ADDRESS RamDiskLBA;
|
| 516 |
|
| 517 | Media = This->Media;
|
| 518 |
|
| 519 | if(BufferSize % Media->BlockSize != 0)
|
| 520 | return EFI_BAD_BUFFER_SIZE;
|
| 521 |
|
| 522 | if(LBA > Media->LastBlock)
|
| 523 | return EFI_DEVICE_ERROR;
|
| 524 |
|
| 525 | if(LBA + BufferSize / Media->BlockSize - 1 > Media->LastBlock)
|
| 526 | return EFI_DEVICE_ERROR;
|
| 527 |
|
| 528 | RamDiskDev = RAM_DISK_FROM_THIS(This);
|
| 529 | RamDiskLBA = RamDiskDev->Start + MultU64x32(LBA,Media->BlockSize);
|
| 530 | CopyMem(Buffer,(VOID*)(UINTN)RamDiskLBA,BufferSize);
|
| 531 |
|
| 532 | return EFI_SUCCESS;
|
| 533 | }
|
| 534 |
|
| 535 |
|
| 536 | /* Implementation of block I/O write */
|
| 537 | STATIC EFI_STATUS RamDiskWriteBlocks(
|
| 538 | IN EFI_BLOCK_IO *This,
|
| 539 | IN UINT32 MediaId,
|
| 540 | IN EFI_LBA LBA,
|
| 541 | IN UINTN BufferSize,
|
| 542 | IN VOID *Buffer)
|
| 543 | {
|
| 544 | EFI_BLOCK_IO_MEDIA *Media;
|
| 545 | RAM_DISK_DEV *RamDiskDev;
|
| 546 | EFI_PHYSICAL_ADDRESS RamDiskLBA;
|
| 547 |
|
| 548 | Media = This->Media;
|
| 549 | if(Media->ReadOnly)
|
| 550 | return EFI_WRITE_PROTECTED;
|
| 551 |
|
| 552 | if(BufferSize % Media->BlockSize != 0)
|
| 553 | return EFI_BAD_BUFFER_SIZE;
|
| 554 |
|
| 555 | if(LBA > Media->LastBlock)
|
| 556 | return EFI_DEVICE_ERROR;
|
| 557 |
|
| 558 | if(LBA + BufferSize / Media->BlockSize - 1 > Media->LastBlock)
|
| 559 | return EFI_DEVICE_ERROR;
|
| 560 |
|
| 561 | RamDiskDev = RAM_DISK_FROM_THIS(This);
|
| 562 | RamDiskLBA = RamDiskDev->Start + MultU64x32(LBA,Media->BlockSize);
|
| 563 | CopyMem((VOID*)(UINTN)RamDiskLBA,Buffer,BufferSize);
|
| 564 |
|
| 565 | return EFI_SUCCESS;
|
| 566 | }
|
| 567 |
|
| 568 | /* Implementation of block I/O flush */
|
| 569 | STATIC EFI_STATUS RamDiskFlushBlocks(
|
| 570 | IN EFI_BLOCK_IO *This)
|
| 571 | {
|
| 572 | return EFI_SUCCESS;
|
| 573 | }
|