1 | /* |
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2 | * fat.c |
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3 | * |
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4 | * Low-level operations on a volume with FAT filesystem |
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5 | * |
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6 | * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia |
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7 | * Author: Eugeny S. Mints <Eugeny.Mints@oktet.ru> |
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8 | */ |
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9 | |
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10 | #if HAVE_CONFIG_H |
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11 | #include "config.h" |
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12 | #endif |
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13 | |
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14 | #include <sys/types.h> |
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15 | #include <sys/stat.h> |
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16 | #include <fcntl.h> |
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17 | #include <unistd.h> |
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18 | #include <errno.h> |
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19 | #include <stdlib.h> |
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20 | |
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21 | #include <rtems/libio_.h> |
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22 | |
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23 | #include "fat.h" |
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24 | #include "fat_fat_operations.h" |
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25 | |
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26 | int |
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27 | fat_buf_access(fat_fs_info_t *fs_info, uint32_t blk, int op_type, |
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28 | rtems_bdbuf_buffer **buf) |
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29 | { |
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30 | rtems_status_code sc = RTEMS_SUCCESSFUL; |
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31 | uint8_t i; |
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32 | bool sec_of_fat; |
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33 | |
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34 | |
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35 | if (fs_info->c.state == FAT_CACHE_EMPTY) |
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36 | { |
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37 | if (op_type == FAT_OP_TYPE_READ) |
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38 | sc = rtems_bdbuf_read(fs_info->vol.dd, blk, &fs_info->c.buf); |
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39 | else |
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40 | sc = rtems_bdbuf_get(fs_info->vol.dd, blk, &fs_info->c.buf); |
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41 | if (sc != RTEMS_SUCCESSFUL) |
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42 | rtems_set_errno_and_return_minus_one(EIO); |
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43 | fs_info->c.blk_num = blk; |
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44 | fs_info->c.modified = 0; |
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45 | fs_info->c.state = FAT_CACHE_ACTUAL; |
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46 | } |
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47 | |
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48 | sec_of_fat = ((fs_info->c.blk_num >= fs_info->vol.fat_loc) && |
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49 | (fs_info->c.blk_num < fs_info->vol.rdir_loc)); |
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50 | |
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51 | if (fs_info->c.blk_num != blk) |
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52 | { |
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53 | if (fs_info->c.modified) |
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54 | { |
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55 | if (sec_of_fat && !fs_info->vol.mirror) |
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56 | memcpy(fs_info->sec_buf, fs_info->c.buf->buffer, |
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57 | fs_info->vol.bps); |
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58 | |
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59 | sc = rtems_bdbuf_release_modified(fs_info->c.buf); |
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60 | fs_info->c.state = FAT_CACHE_EMPTY; |
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61 | fs_info->c.modified = 0; |
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62 | if (sc != RTEMS_SUCCESSFUL) |
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63 | rtems_set_errno_and_return_minus_one(EIO); |
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64 | |
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65 | if (sec_of_fat && !fs_info->vol.mirror) |
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66 | { |
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67 | rtems_bdbuf_buffer *b; |
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68 | |
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69 | for (i = 1; i < fs_info->vol.fats; i++) |
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70 | { |
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71 | sc = rtems_bdbuf_get(fs_info->vol.dd, |
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72 | fs_info->c.blk_num + |
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73 | fs_info->vol.fat_length * i, |
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74 | &b); |
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75 | if ( sc != RTEMS_SUCCESSFUL) |
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76 | rtems_set_errno_and_return_minus_one(ENOMEM); |
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77 | memcpy(b->buffer, fs_info->sec_buf, fs_info->vol.bps); |
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78 | sc = rtems_bdbuf_release_modified(b); |
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79 | if ( sc != RTEMS_SUCCESSFUL) |
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80 | rtems_set_errno_and_return_minus_one(ENOMEM); |
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81 | } |
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82 | } |
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83 | } |
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84 | else |
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85 | { |
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86 | sc = rtems_bdbuf_release(fs_info->c.buf); |
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87 | fs_info->c.state = FAT_CACHE_EMPTY; |
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88 | if (sc != RTEMS_SUCCESSFUL) |
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89 | rtems_set_errno_and_return_minus_one(EIO); |
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90 | |
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91 | } |
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92 | if (op_type == FAT_OP_TYPE_READ) |
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93 | sc = rtems_bdbuf_read(fs_info->vol.dd, blk, &fs_info->c.buf); |
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94 | else |
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95 | sc = rtems_bdbuf_get(fs_info->vol.dd, blk, &fs_info->c.buf); |
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96 | if (sc != RTEMS_SUCCESSFUL) |
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97 | rtems_set_errno_and_return_minus_one(EIO); |
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98 | fs_info->c.blk_num = blk; |
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99 | fs_info->c.state = FAT_CACHE_ACTUAL; |
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100 | } |
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101 | *buf = fs_info->c.buf; |
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102 | return RC_OK; |
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103 | } |
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104 | |
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105 | int |
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106 | fat_buf_release(fat_fs_info_t *fs_info) |
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107 | { |
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108 | rtems_status_code sc = RTEMS_SUCCESSFUL; |
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109 | uint8_t i; |
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110 | bool sec_of_fat; |
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111 | |
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112 | if (fs_info->c.state == FAT_CACHE_EMPTY) |
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113 | return RC_OK; |
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114 | |
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115 | sec_of_fat = ((fs_info->c.blk_num >= fs_info->vol.fat_loc) && |
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116 | (fs_info->c.blk_num < fs_info->vol.rdir_loc)); |
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117 | |
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118 | if (fs_info->c.modified) |
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119 | { |
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120 | if (sec_of_fat && !fs_info->vol.mirror) |
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121 | memcpy(fs_info->sec_buf, fs_info->c.buf->buffer, fs_info->vol.bps); |
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122 | |
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123 | sc = rtems_bdbuf_release_modified(fs_info->c.buf); |
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124 | if (sc != RTEMS_SUCCESSFUL) |
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125 | rtems_set_errno_and_return_minus_one(EIO); |
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126 | fs_info->c.modified = 0; |
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127 | |
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128 | if (sec_of_fat && !fs_info->vol.mirror) |
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129 | { |
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130 | rtems_bdbuf_buffer *b; |
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131 | |
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132 | for (i = 1; i < fs_info->vol.fats; i++) |
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133 | { |
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134 | sc = rtems_bdbuf_get(fs_info->vol.dd, |
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135 | fs_info->c.blk_num + |
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136 | fs_info->vol.fat_length * i, |
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137 | &b); |
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138 | if ( sc != RTEMS_SUCCESSFUL) |
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139 | rtems_set_errno_and_return_minus_one(ENOMEM); |
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140 | memcpy(b->buffer, fs_info->sec_buf, fs_info->vol.bps); |
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141 | sc = rtems_bdbuf_release_modified(b); |
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142 | if ( sc != RTEMS_SUCCESSFUL) |
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143 | rtems_set_errno_and_return_minus_one(ENOMEM); |
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144 | } |
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145 | } |
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146 | } |
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147 | else |
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148 | { |
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149 | sc = rtems_bdbuf_release(fs_info->c.buf); |
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150 | if (sc != RTEMS_SUCCESSFUL) |
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151 | rtems_set_errno_and_return_minus_one(EIO); |
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152 | } |
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153 | fs_info->c.state = FAT_CACHE_EMPTY; |
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154 | return RC_OK; |
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155 | } |
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156 | |
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157 | /* _fat_block_read -- |
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158 | * This function reads 'count' bytes from device filesystem is mounted on, |
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159 | * starts at 'start+offset' position where 'start' computed in sectors |
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160 | * and 'offset' is offset inside sector (reading may cross sectors |
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161 | * boundary; in this case assumed we want to read sequential sector(s)) |
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162 | * |
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163 | * PARAMETERS: |
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164 | * fs_info - FS info |
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165 | * start - sector num to start read from |
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166 | * offset - offset inside sector 'start' |
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167 | * count - count of bytes to read |
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168 | * buff - buffer provided by user |
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169 | * |
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170 | * RETURNS: |
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171 | * bytes read on success, or -1 if error occured |
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172 | * and errno set appropriately |
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173 | */ |
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174 | ssize_t |
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175 | _fat_block_read( |
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176 | fat_fs_info_t *fs_info, |
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177 | uint32_t start, |
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178 | uint32_t offset, |
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179 | uint32_t count, |
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180 | void *buff |
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181 | ) |
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182 | { |
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183 | int rc = RC_OK; |
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184 | ssize_t cmpltd = 0; |
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185 | uint32_t blk = start; |
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186 | uint32_t ofs = offset; |
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187 | rtems_bdbuf_buffer *block = NULL; |
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188 | uint32_t c = 0; |
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189 | |
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190 | while (count > 0) |
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191 | { |
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192 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_READ, &block); |
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193 | if (rc != RC_OK) |
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194 | return -1; |
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195 | |
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196 | c = MIN(count, (fs_info->vol.bps - ofs)); |
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197 | memcpy((buff + cmpltd), (block->buffer + ofs), c); |
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198 | |
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199 | count -= c; |
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200 | cmpltd += c; |
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201 | blk++; |
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202 | ofs = 0; |
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203 | } |
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204 | return cmpltd; |
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205 | } |
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206 | |
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207 | /* _fat_block_write -- |
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208 | * This function write 'count' bytes to device filesystem is mounted on, |
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209 | * starts at 'start+offset' position where 'start' computed in sectors |
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210 | * and 'offset' is offset inside sector (writing may cross sectors |
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211 | * boundary; in this case assumed we want to write sequential sector(s)) |
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212 | * |
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213 | * PARAMETERS: |
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214 | * fs_info - FS info |
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215 | * start - sector num to start read from |
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216 | * offset - offset inside sector 'start' |
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217 | * count - count of bytes to write |
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218 | * buff - buffer provided by user |
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219 | * |
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220 | * RETURNS: |
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221 | * bytes written on success, or -1 if error occured |
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222 | * and errno set appropriately |
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223 | */ |
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224 | ssize_t |
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225 | _fat_block_write( |
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226 | fat_fs_info_t *fs_info, |
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227 | uint32_t start, |
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228 | uint32_t offset, |
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229 | uint32_t count, |
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230 | const void *buff) |
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231 | { |
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232 | int rc = RC_OK; |
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233 | ssize_t cmpltd = 0; |
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234 | uint32_t blk = start; |
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235 | uint32_t ofs = offset; |
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236 | rtems_bdbuf_buffer *block = NULL; |
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237 | uint32_t c = 0; |
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238 | |
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239 | while(count > 0) |
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240 | { |
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241 | c = MIN(count, (fs_info->vol.bps - ofs)); |
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242 | |
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243 | if (c == fs_info->vol.bps) |
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244 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_GET, &block); |
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245 | else |
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246 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_READ, &block); |
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247 | if (rc != RC_OK) |
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248 | return -1; |
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249 | |
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250 | memcpy((block->buffer + ofs), (buff + cmpltd), c); |
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251 | |
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252 | fat_buf_mark_modified(fs_info); |
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253 | |
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254 | count -= c; |
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255 | cmpltd +=c; |
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256 | blk++; |
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257 | ofs = 0; |
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258 | } |
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259 | return cmpltd; |
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260 | } |
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261 | |
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262 | int |
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263 | _fat_block_zero( |
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264 | fat_fs_info_t *fs_info, |
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265 | uint32_t start, |
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266 | uint32_t offset, |
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267 | uint32_t count) |
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268 | { |
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269 | int rc = RC_OK; |
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270 | uint32_t blk = start; |
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271 | uint32_t ofs = offset; |
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272 | rtems_bdbuf_buffer *block = NULL; |
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273 | uint32_t c = 0; |
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274 | |
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275 | while(count > 0) |
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276 | { |
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277 | c = MIN(count, (fs_info->vol.bps - ofs)); |
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278 | |
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279 | if (c == fs_info->vol.bps) |
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280 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_GET, &block); |
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281 | else |
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282 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_READ, &block); |
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283 | if (rc != RC_OK) |
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284 | return -1; |
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285 | |
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286 | memset((block->buffer + ofs), 0, c); |
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287 | |
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288 | fat_buf_mark_modified(fs_info); |
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289 | |
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290 | count -= c; |
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291 | blk++; |
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292 | ofs = 0; |
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293 | } |
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294 | return 0; |
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295 | } |
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296 | |
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297 | /* _fat_block_release -- |
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298 | * This function works around the hack that hold a bdbuf and does |
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299 | * not release it. |
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300 | * |
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301 | * PARAMETERS: |
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302 | * fs_info - FS info |
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303 | * |
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304 | * RETURNS: |
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305 | * 0 on success, or -1 if error occured and errno set appropriately |
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306 | */ |
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307 | int |
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308 | _fat_block_release(fat_fs_info_t *fs_info) |
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309 | { |
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310 | return fat_buf_release(fs_info); |
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311 | } |
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312 | |
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313 | /* fat_cluster_read -- |
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314 | * wrapper for reading a whole cluster at once |
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315 | * |
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316 | * PARAMETERS: |
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317 | * fs_info - FS info |
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318 | * cln - number of cluster to read |
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319 | * buff - buffer provided by user |
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320 | * |
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321 | * RETURNS: |
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322 | * bytes read on success, or -1 if error occured |
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323 | * and errno set appropriately |
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324 | */ |
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325 | ssize_t |
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326 | fat_cluster_read( |
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327 | fat_fs_info_t *fs_info, |
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328 | uint32_t cln, |
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329 | void *buff |
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330 | ) |
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331 | { |
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332 | uint32_t fsec = 0; |
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333 | |
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334 | fsec = fat_cluster_num_to_sector_num(fs_info, cln); |
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335 | |
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336 | return _fat_block_read(fs_info, fsec, 0, |
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337 | fs_info->vol.spc << fs_info->vol.sec_log2, buff); |
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338 | } |
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339 | |
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340 | /* fat_cluster_write -- |
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341 | * wrapper for writting a whole cluster at once |
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342 | * |
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343 | * PARAMETERS: |
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344 | * fs_info - FS info |
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345 | * cln - number of cluster to write |
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346 | * buff - buffer provided by user |
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347 | * |
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348 | * RETURNS: |
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349 | * bytes written on success, or -1 if error occured |
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350 | * and errno set appropriately |
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351 | */ |
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352 | ssize_t |
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353 | fat_cluster_write( |
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354 | fat_fs_info_t *fs_info, |
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355 | uint32_t cln, |
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356 | const void *buff |
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357 | ) |
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358 | { |
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359 | uint32_t fsec = 0; |
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360 | |
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361 | fsec = fat_cluster_num_to_sector_num(fs_info, cln); |
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362 | |
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363 | return _fat_block_write(fs_info, fsec, 0, |
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364 | fs_info->vol.spc << fs_info->vol.sec_log2, buff); |
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365 | } |
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366 | |
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367 | /* fat_init_volume_info -- |
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368 | * Get inforamtion about volume on which filesystem is mounted on |
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369 | * |
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370 | * PARAMETERS: |
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371 | * fs_info - FS info |
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372 | * |
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373 | * RETURNS: |
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374 | * RC_OK on success, or -1 if error occured |
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375 | * and errno set appropriately |
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376 | */ |
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377 | int |
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378 | fat_init_volume_info(fat_fs_info_t *fs_info, const char *device) |
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379 | { |
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380 | rtems_status_code sc = RTEMS_SUCCESSFUL; |
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381 | int rc = RC_OK; |
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382 | register fat_vol_t *vol = &fs_info->vol; |
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383 | uint32_t data_secs = 0; |
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384 | char boot_rec[FAT_MAX_BPB_SIZE]; |
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385 | char fs_info_sector[FAT_USEFUL_INFO_SIZE]; |
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386 | ssize_t ret = 0; |
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387 | struct stat stat_buf; |
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388 | int i = 0; |
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389 | rtems_bdbuf_buffer *block = NULL; |
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390 | |
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391 | vol->fd = open(device, O_RDWR); |
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392 | if (vol->fd < 0) |
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393 | { |
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394 | rtems_set_errno_and_return_minus_one(ENXIO); |
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395 | } |
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396 | |
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397 | rc = fstat(vol->fd, &stat_buf); |
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398 | if (rc != 0) |
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399 | { |
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400 | close(vol->fd); |
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401 | rtems_set_errno_and_return_minus_one(ENXIO); |
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402 | } |
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403 | |
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404 | /* Must be a block device. */ |
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405 | if (!S_ISBLK(stat_buf.st_mode)) |
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406 | { |
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407 | close(vol->fd); |
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408 | rtems_set_errno_and_return_minus_one(ENXIO); |
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409 | } |
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410 | |
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411 | /* check that device is registred as block device and lock it */ |
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412 | rc = rtems_disk_fd_get_disk_device(vol->fd, &vol->dd); |
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413 | if (rc != 0) { |
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414 | close(vol->fd); |
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415 | rtems_set_errno_and_return_minus_one(ENXIO); |
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416 | } |
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417 | |
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418 | /* Read boot record */ |
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419 | /* FIXME: Asserts FAT_MAX_BPB_SIZE < bdbuf block size */ |
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420 | sc = rtems_bdbuf_read( vol->dd, 0, &block); |
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421 | if (sc != RTEMS_SUCCESSFUL) |
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422 | { |
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423 | close(vol->fd); |
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424 | rtems_set_errno_and_return_minus_one( EIO); |
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425 | } |
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426 | |
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427 | memcpy( boot_rec, block->buffer, FAT_MAX_BPB_SIZE); |
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428 | |
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429 | sc = rtems_bdbuf_release( block); |
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430 | if (sc != RTEMS_SUCCESSFUL) |
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431 | { |
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432 | close(vol->fd); |
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433 | rtems_set_errno_and_return_minus_one( EIO ); |
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434 | } |
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435 | |
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436 | /* Evaluate boot record */ |
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437 | vol->bps = FAT_GET_BR_BYTES_PER_SECTOR(boot_rec); |
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438 | |
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439 | if ( (vol->bps != 512) && |
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440 | (vol->bps != 1024) && |
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441 | (vol->bps != 2048) && |
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442 | (vol->bps != 4096)) |
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443 | { |
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444 | close(vol->fd); |
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445 | rtems_set_errno_and_return_minus_one( EINVAL ); |
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446 | } |
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447 | |
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448 | for (vol->sec_mul = 0, i = (vol->bps >> FAT_SECTOR512_BITS); (i & 1) == 0; |
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449 | i >>= 1, vol->sec_mul++); |
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450 | for (vol->sec_log2 = 0, i = vol->bps; (i & 1) == 0; |
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451 | i >>= 1, vol->sec_log2++); |
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452 | |
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453 | vol->spc = FAT_GET_BR_SECTORS_PER_CLUSTER(boot_rec); |
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454 | /* |
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455 | * "sectors per cluster" of zero is invalid |
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456 | * (and would hang the following loop) |
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457 | */ |
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458 | if (vol->spc == 0) |
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459 | { |
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460 | close(vol->fd); |
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461 | rtems_set_errno_and_return_minus_one(EINVAL); |
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462 | } |
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463 | |
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464 | for (vol->spc_log2 = 0, i = vol->spc; (i & 1) == 0; |
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465 | i >>= 1, vol->spc_log2++); |
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466 | |
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467 | /* |
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468 | * "bytes per cluster" value greater than 32K is invalid |
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469 | */ |
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470 | if ((vol->bpc = vol->bps << vol->spc_log2) > MS_BYTES_PER_CLUSTER_LIMIT) |
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471 | { |
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472 | close(vol->fd); |
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473 | rtems_set_errno_and_return_minus_one(EINVAL); |
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474 | } |
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475 | |
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476 | for (vol->bpc_log2 = 0, i = vol->bpc; (i & 1) == 0; |
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477 | i >>= 1, vol->bpc_log2++); |
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478 | |
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479 | vol->fats = FAT_GET_BR_FAT_NUM(boot_rec); |
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480 | vol->fat_loc = FAT_GET_BR_RESERVED_SECTORS_NUM(boot_rec); |
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481 | |
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482 | vol->rdir_entrs = FAT_GET_BR_FILES_PER_ROOT_DIR(boot_rec); |
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483 | |
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484 | /* calculate the count of sectors occupied by the root directory */ |
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485 | vol->rdir_secs = ((vol->rdir_entrs * FAT_DIRENTRY_SIZE) + (vol->bps - 1)) / |
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486 | vol->bps; |
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487 | |
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488 | vol->rdir_size = vol->rdir_secs << vol->sec_log2; |
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489 | |
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490 | if ( (FAT_GET_BR_SECTORS_PER_FAT(boot_rec)) != 0) |
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491 | vol->fat_length = FAT_GET_BR_SECTORS_PER_FAT(boot_rec); |
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492 | else |
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493 | vol->fat_length = FAT_GET_BR_SECTORS_PER_FAT32(boot_rec); |
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494 | |
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495 | vol->data_fsec = vol->fat_loc + vol->fats * vol->fat_length + |
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496 | vol->rdir_secs; |
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497 | |
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498 | /* for FAT12/16 root dir starts at(sector) */ |
---|
499 | vol->rdir_loc = vol->fat_loc + vol->fats * vol->fat_length; |
---|
500 | |
---|
501 | if ( (FAT_GET_BR_TOTAL_SECTORS_NUM16(boot_rec)) != 0) |
---|
502 | vol->tot_secs = FAT_GET_BR_TOTAL_SECTORS_NUM16(boot_rec); |
---|
503 | else |
---|
504 | vol->tot_secs = FAT_GET_BR_TOTAL_SECTORS_NUM32(boot_rec); |
---|
505 | |
---|
506 | data_secs = vol->tot_secs - vol->data_fsec; |
---|
507 | |
---|
508 | vol->data_cls = data_secs / vol->spc; |
---|
509 | |
---|
510 | /* determine FAT type at least */ |
---|
511 | if ( vol->data_cls < FAT_FAT12_MAX_CLN) |
---|
512 | { |
---|
513 | vol->type = FAT_FAT12; |
---|
514 | vol->mask = FAT_FAT12_MASK; |
---|
515 | vol->eoc_val = FAT_FAT12_EOC; |
---|
516 | } |
---|
517 | else |
---|
518 | { |
---|
519 | if ( vol->data_cls < FAT_FAT16_MAX_CLN) |
---|
520 | { |
---|
521 | vol->type = FAT_FAT16; |
---|
522 | vol->mask = FAT_FAT16_MASK; |
---|
523 | vol->eoc_val = FAT_FAT16_EOC; |
---|
524 | } |
---|
525 | else |
---|
526 | { |
---|
527 | vol->type = FAT_FAT32; |
---|
528 | vol->mask = FAT_FAT32_MASK; |
---|
529 | vol->eoc_val = FAT_FAT32_EOC; |
---|
530 | } |
---|
531 | } |
---|
532 | |
---|
533 | if (vol->type == FAT_FAT32) |
---|
534 | { |
---|
535 | vol->rdir_cl = FAT_GET_BR_FAT32_ROOT_CLUSTER(boot_rec); |
---|
536 | |
---|
537 | vol->mirror = FAT_GET_BR_EXT_FLAGS(boot_rec) & FAT_BR_EXT_FLAGS_MIRROR; |
---|
538 | if (vol->mirror) |
---|
539 | vol->afat = FAT_GET_BR_EXT_FLAGS(boot_rec) & FAT_BR_EXT_FLAGS_FAT_NUM; |
---|
540 | else |
---|
541 | vol->afat = 0; |
---|
542 | |
---|
543 | vol->info_sec = FAT_GET_BR_FAT32_FS_INFO_SECTOR(boot_rec); |
---|
544 | if( vol->info_sec == 0 ) |
---|
545 | { |
---|
546 | close(vol->fd); |
---|
547 | rtems_set_errno_and_return_minus_one( EINVAL ); |
---|
548 | } |
---|
549 | else |
---|
550 | { |
---|
551 | ret = _fat_block_read(fs_info, vol->info_sec , 0, |
---|
552 | FAT_FSI_LEADSIG_SIZE, fs_info_sector); |
---|
553 | if ( ret < 0 ) |
---|
554 | { |
---|
555 | close(vol->fd); |
---|
556 | return -1; |
---|
557 | } |
---|
558 | |
---|
559 | if (FAT_GET_FSINFO_LEAD_SIGNATURE(fs_info_sector) != |
---|
560 | FAT_FSINFO_LEAD_SIGNATURE_VALUE) |
---|
561 | { |
---|
562 | _fat_block_release(fs_info); |
---|
563 | close(vol->fd); |
---|
564 | rtems_set_errno_and_return_minus_one( EINVAL ); |
---|
565 | } |
---|
566 | else |
---|
567 | { |
---|
568 | ret = _fat_block_read(fs_info, vol->info_sec , FAT_FSI_INFO, |
---|
569 | FAT_USEFUL_INFO_SIZE, fs_info_sector); |
---|
570 | if ( ret < 0 ) |
---|
571 | { |
---|
572 | _fat_block_release(fs_info); |
---|
573 | close(vol->fd); |
---|
574 | return -1; |
---|
575 | } |
---|
576 | |
---|
577 | vol->free_cls = FAT_GET_FSINFO_FREE_CLUSTER_COUNT(fs_info_sector); |
---|
578 | vol->next_cl = FAT_GET_FSINFO_NEXT_FREE_CLUSTER(fs_info_sector); |
---|
579 | rc = fat_fat32_update_fsinfo_sector(fs_info, 0xFFFFFFFF, |
---|
580 | 0xFFFFFFFF); |
---|
581 | if ( rc != RC_OK ) |
---|
582 | { |
---|
583 | _fat_block_release(fs_info); |
---|
584 | close(vol->fd); |
---|
585 | return rc; |
---|
586 | } |
---|
587 | } |
---|
588 | } |
---|
589 | } |
---|
590 | else |
---|
591 | { |
---|
592 | vol->rdir_cl = 0; |
---|
593 | vol->mirror = 0; |
---|
594 | vol->afat = 0; |
---|
595 | vol->free_cls = 0xFFFFFFFF; |
---|
596 | vol->next_cl = 0xFFFFFFFF; |
---|
597 | } |
---|
598 | |
---|
599 | _fat_block_release(fs_info); |
---|
600 | |
---|
601 | vol->afat_loc = vol->fat_loc + vol->fat_length * vol->afat; |
---|
602 | |
---|
603 | /* set up collection of fat-files fd */ |
---|
604 | fs_info->vhash = calloc(FAT_HASH_SIZE, sizeof(rtems_chain_control)); |
---|
605 | if ( fs_info->vhash == NULL ) |
---|
606 | { |
---|
607 | close(vol->fd); |
---|
608 | rtems_set_errno_and_return_minus_one( ENOMEM ); |
---|
609 | } |
---|
610 | |
---|
611 | for (i = 0; i < FAT_HASH_SIZE; i++) |
---|
612 | rtems_chain_initialize_empty(fs_info->vhash + i); |
---|
613 | |
---|
614 | fs_info->rhash = calloc(FAT_HASH_SIZE, sizeof(rtems_chain_control)); |
---|
615 | if ( fs_info->rhash == NULL ) |
---|
616 | { |
---|
617 | close(vol->fd); |
---|
618 | free(fs_info->vhash); |
---|
619 | rtems_set_errno_and_return_minus_one( ENOMEM ); |
---|
620 | } |
---|
621 | for (i = 0; i < FAT_HASH_SIZE; i++) |
---|
622 | rtems_chain_initialize_empty(fs_info->rhash + i); |
---|
623 | |
---|
624 | fs_info->uino_pool_size = FAT_UINO_POOL_INIT_SIZE; |
---|
625 | fs_info->uino_base = (vol->tot_secs << vol->sec_mul) << 4; |
---|
626 | fs_info->index = 0; |
---|
627 | fs_info->uino = (char *)calloc(fs_info->uino_pool_size, sizeof(char)); |
---|
628 | if ( fs_info->uino == NULL ) |
---|
629 | { |
---|
630 | close(vol->fd); |
---|
631 | free(fs_info->vhash); |
---|
632 | free(fs_info->rhash); |
---|
633 | rtems_set_errno_and_return_minus_one( ENOMEM ); |
---|
634 | } |
---|
635 | fs_info->sec_buf = (uint8_t *)calloc(vol->bps, sizeof(uint8_t)); |
---|
636 | if (fs_info->sec_buf == NULL) |
---|
637 | { |
---|
638 | close(vol->fd); |
---|
639 | free(fs_info->vhash); |
---|
640 | free(fs_info->rhash); |
---|
641 | free(fs_info->uino); |
---|
642 | rtems_set_errno_and_return_minus_one( ENOMEM ); |
---|
643 | } |
---|
644 | |
---|
645 | return RC_OK; |
---|
646 | } |
---|
647 | |
---|
648 | /* fat_shutdown_drive -- |
---|
649 | * Free all allocated resources and synchronize all necessary data |
---|
650 | * |
---|
651 | * PARAMETERS: |
---|
652 | * fs_info - FS info |
---|
653 | * |
---|
654 | * RETURNS: |
---|
655 | * RC_OK on success, or -1 if error occured |
---|
656 | * and errno set appropriately |
---|
657 | */ |
---|
658 | int |
---|
659 | fat_shutdown_drive(fat_fs_info_t *fs_info) |
---|
660 | { |
---|
661 | int rc = RC_OK; |
---|
662 | int i = 0; |
---|
663 | |
---|
664 | if (fs_info->vol.type & FAT_FAT32) |
---|
665 | { |
---|
666 | rc = fat_fat32_update_fsinfo_sector(fs_info, fs_info->vol.free_cls, |
---|
667 | fs_info->vol.next_cl); |
---|
668 | if ( rc != RC_OK ) |
---|
669 | rc = -1; |
---|
670 | } |
---|
671 | |
---|
672 | fat_buf_release(fs_info); |
---|
673 | |
---|
674 | if (rtems_bdbuf_syncdev(fs_info->vol.dd) != RTEMS_SUCCESSFUL) |
---|
675 | rc = -1; |
---|
676 | |
---|
677 | for (i = 0; i < FAT_HASH_SIZE; i++) |
---|
678 | { |
---|
679 | rtems_chain_node *node = NULL; |
---|
680 | rtems_chain_control *the_chain = fs_info->vhash + i; |
---|
681 | |
---|
682 | while ( (node = rtems_chain_get(the_chain)) != NULL ) |
---|
683 | free(node); |
---|
684 | } |
---|
685 | |
---|
686 | for (i = 0; i < FAT_HASH_SIZE; i++) |
---|
687 | { |
---|
688 | rtems_chain_node *node = NULL; |
---|
689 | rtems_chain_control *the_chain = fs_info->rhash + i; |
---|
690 | |
---|
691 | while ( (node = rtems_chain_get(the_chain)) != NULL ) |
---|
692 | free(node); |
---|
693 | } |
---|
694 | |
---|
695 | free(fs_info->vhash); |
---|
696 | free(fs_info->rhash); |
---|
697 | |
---|
698 | free(fs_info->uino); |
---|
699 | free(fs_info->sec_buf); |
---|
700 | close(fs_info->vol.fd); |
---|
701 | |
---|
702 | if (rc) |
---|
703 | errno = EIO; |
---|
704 | return rc; |
---|
705 | } |
---|
706 | |
---|
707 | /* fat_init_clusters_chain -- |
---|
708 | * Zeroing contents of all clusters in the chain |
---|
709 | * |
---|
710 | * PARAMETERS: |
---|
711 | * fs_info - FS info |
---|
712 | * start_cluster_num - num of first cluster in the chain |
---|
713 | * |
---|
714 | * RETURNS: |
---|
715 | * RC_OK on success, or -1 if error occured |
---|
716 | * and errno set appropriately |
---|
717 | */ |
---|
718 | int |
---|
719 | fat_init_clusters_chain( |
---|
720 | fat_fs_info_t *fs_info, |
---|
721 | uint32_t start_cln |
---|
722 | ) |
---|
723 | { |
---|
724 | int rc = RC_OK; |
---|
725 | ssize_t ret = 0; |
---|
726 | uint32_t cur_cln = start_cln; |
---|
727 | char *buf; |
---|
728 | |
---|
729 | buf = calloc(fs_info->vol.bpc, sizeof(char)); |
---|
730 | if ( buf == NULL ) |
---|
731 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
732 | |
---|
733 | while ((cur_cln & fs_info->vol.mask) < fs_info->vol.eoc_val) |
---|
734 | { |
---|
735 | ret = fat_cluster_write(fs_info, cur_cln, buf); |
---|
736 | if ( ret == -1 ) |
---|
737 | { |
---|
738 | free(buf); |
---|
739 | return -1; |
---|
740 | } |
---|
741 | |
---|
742 | rc = fat_get_fat_cluster(fs_info, cur_cln, &cur_cln); |
---|
743 | if ( rc != RC_OK ) |
---|
744 | { |
---|
745 | free(buf); |
---|
746 | return rc; |
---|
747 | } |
---|
748 | |
---|
749 | } |
---|
750 | free(buf); |
---|
751 | return rc; |
---|
752 | } |
---|
753 | |
---|
754 | #define FAT_UNIQ_INO_BASE 0x0FFFFF00 |
---|
755 | |
---|
756 | #define FAT_UNIQ_INO_IS_BUSY(index, arr) \ |
---|
757 | (((arr)[((index)>>3)]>>((index) & (8-1))) & 0x01) |
---|
758 | |
---|
759 | #define FAT_SET_UNIQ_INO_BUSY(index, arr) \ |
---|
760 | ((arr)[((index)>>3)] |= (0x01<<((index) & (8-1)))) |
---|
761 | |
---|
762 | #define FAT_SET_UNIQ_INO_FREE(index, arr) \ |
---|
763 | ((arr)[((index)>>3)] &= (~(0x01<<((index) & (8-1))))) |
---|
764 | |
---|
765 | /* fat_get_unique_ino -- |
---|
766 | * Allocate unique ino from unique ino pool |
---|
767 | * |
---|
768 | * PARAMETERS: |
---|
769 | * fs_info - FS info |
---|
770 | * |
---|
771 | * RETURNS: |
---|
772 | * unique inode number on success, or 0 if there is no free unique inode |
---|
773 | * number in the pool |
---|
774 | * |
---|
775 | * ATTENTION: |
---|
776 | * 0 means FAILED !!! |
---|
777 | * |
---|
778 | */ |
---|
779 | uint32_t |
---|
780 | fat_get_unique_ino(fat_fs_info_t *fs_info) |
---|
781 | { |
---|
782 | uint32_t j = 0; |
---|
783 | bool resrc_unsuff = false; |
---|
784 | |
---|
785 | while (!resrc_unsuff) |
---|
786 | { |
---|
787 | for (j = 0; j < fs_info->uino_pool_size; j++) |
---|
788 | { |
---|
789 | if (!FAT_UNIQ_INO_IS_BUSY(fs_info->index, fs_info->uino)) |
---|
790 | { |
---|
791 | FAT_SET_UNIQ_INO_BUSY(fs_info->index, fs_info->uino); |
---|
792 | return (fs_info->uino_base + fs_info->index); |
---|
793 | } |
---|
794 | fs_info->index++; |
---|
795 | if (fs_info->index >= fs_info->uino_pool_size) |
---|
796 | fs_info->index = 0; |
---|
797 | } |
---|
798 | |
---|
799 | if ((fs_info->uino_pool_size << 1) < (0x0FFFFFFF - fs_info->uino_base)) |
---|
800 | { |
---|
801 | fs_info->uino_pool_size <<= 1; |
---|
802 | fs_info->uino = realloc(fs_info->uino, fs_info->uino_pool_size); |
---|
803 | if (fs_info->uino != NULL) |
---|
804 | fs_info->index = fs_info->uino_pool_size; |
---|
805 | else |
---|
806 | resrc_unsuff = true; |
---|
807 | } |
---|
808 | else |
---|
809 | resrc_unsuff = true; |
---|
810 | } |
---|
811 | return 0; |
---|
812 | } |
---|
813 | |
---|
814 | /* fat_free_unique_ino -- |
---|
815 | * Return unique ino to unique ino pool |
---|
816 | * |
---|
817 | * PARAMETERS: |
---|
818 | * fs_info - FS info |
---|
819 | * ino - inode number to free |
---|
820 | * |
---|
821 | * RETURNS: |
---|
822 | * None |
---|
823 | */ |
---|
824 | void |
---|
825 | fat_free_unique_ino( |
---|
826 | fat_fs_info_t *fs_info, |
---|
827 | uint32_t ino |
---|
828 | ) |
---|
829 | { |
---|
830 | FAT_SET_UNIQ_INO_FREE((ino - fs_info->uino_base), fs_info->uino); |
---|
831 | } |
---|
832 | |
---|
833 | /* fat_ino_is_unique -- |
---|
834 | * Test whether ino is from unique ino pool |
---|
835 | * |
---|
836 | * PARAMETERS: |
---|
837 | * fs_info - FS info |
---|
838 | * ino - ino to be tested |
---|
839 | * |
---|
840 | * RETURNS: |
---|
841 | * true if ino is allocated from unique ino pool, false otherwise |
---|
842 | */ |
---|
843 | inline bool |
---|
844 | fat_ino_is_unique( |
---|
845 | fat_fs_info_t *fs_info, |
---|
846 | uint32_t ino |
---|
847 | ) |
---|
848 | { |
---|
849 | |
---|
850 | return (ino >= fs_info->uino_base); |
---|
851 | } |
---|
852 | |
---|
853 | /* fat_fat32_update_fsinfo_sector -- |
---|
854 | * Synchronize fsinfo sector for FAT32 volumes |
---|
855 | * |
---|
856 | * PARAMETERS: |
---|
857 | * fs_info - FS info |
---|
858 | * free_count - count of free clusters |
---|
859 | * next_free - the next free cluster num |
---|
860 | * |
---|
861 | * RETURNS: |
---|
862 | * RC_OK on success, or -1 if error occured (errno set appropriately) |
---|
863 | */ |
---|
864 | int |
---|
865 | fat_fat32_update_fsinfo_sector( |
---|
866 | fat_fs_info_t *fs_info, |
---|
867 | uint32_t free_count, |
---|
868 | uint32_t next_free |
---|
869 | ) |
---|
870 | { |
---|
871 | ssize_t ret1 = 0, ret2 = 0; |
---|
872 | uint32_t le_free_count = 0; |
---|
873 | uint32_t le_next_free = 0; |
---|
874 | |
---|
875 | le_free_count = CT_LE_L(free_count); |
---|
876 | le_next_free = CT_LE_L(next_free); |
---|
877 | |
---|
878 | ret1 = _fat_block_write(fs_info, |
---|
879 | fs_info->vol.info_sec, |
---|
880 | FAT_FSINFO_FREE_CLUSTER_COUNT_OFFSET, |
---|
881 | 4, |
---|
882 | (char *)(&le_free_count)); |
---|
883 | |
---|
884 | ret2 = _fat_block_write(fs_info, |
---|
885 | fs_info->vol.info_sec, |
---|
886 | FAT_FSINFO_NEXT_FREE_CLUSTER_OFFSET, |
---|
887 | 4, |
---|
888 | (char *)(&le_next_free)); |
---|
889 | |
---|
890 | if ( (ret1 < 0) || (ret2 < 0) ) |
---|
891 | return -1; |
---|
892 | |
---|
893 | return RC_OK; |
---|
894 | } |
---|