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 | * @(#) $Id$ |
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10 | */ |
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11 | |
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12 | #include <sys/types.h> |
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13 | #include <sys/stat.h> |
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14 | #include <fcntl.h> |
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15 | #include <unistd.h> |
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16 | #include <errno.h> |
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17 | #include <stdlib.h> |
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18 | #include <assert.h> |
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19 | |
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20 | #include <rtems/libio_.h> |
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21 | |
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22 | #include "fat.h" |
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23 | #include "fat_fat_operations.h" |
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24 | |
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25 | /* _fat_block_read -- |
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26 | * This function reads 'count' bytes from device filesystem is mounted on, |
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27 | * starts at 'start+offset' position where 'start' computed in sectors |
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28 | * and 'offset' is offset inside sector (reading may cross sectors |
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29 | * boundary; in this case assumed we want to read sequential sector(s)) |
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30 | * |
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31 | * PARAMETERS: |
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32 | * mt_entry - mount table entry |
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33 | * start - sector num to start read from |
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34 | * offset - offset inside sector 'start' |
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35 | * count - count of bytes to read |
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36 | * buff - buffer provided by user |
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37 | * |
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38 | * RETURNS: |
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39 | * bytes read on success, or -1 if error occured |
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40 | * and errno set appropriately |
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41 | */ |
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42 | ssize_t |
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43 | _fat_block_read( |
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44 | rtems_filesystem_mount_table_entry_t *mt_entry, |
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45 | unsigned32 start, |
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46 | unsigned32 offset, |
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47 | unsigned32 count, |
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48 | void *buff |
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49 | ) |
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50 | { |
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51 | int rc = RC_OK; |
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52 | register fat_fs_info_t *fs_info = mt_entry->fs_info; |
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53 | ssize_t cmpltd = 0; |
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54 | unsigned32 blk = start; |
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55 | unsigned32 ofs = offset; |
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56 | bdbuf_buffer *block = NULL; |
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57 | unsigned32 c = 0; |
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58 | |
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59 | while (count > 0) |
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60 | { |
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61 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_READ, &block); |
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62 | if (rc != RC_OK) |
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63 | return rc; |
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64 | |
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65 | c = MIN(count, (fs_info->vol.bps - ofs)); |
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66 | memcpy((buff + cmpltd), (block->buffer + ofs), c); |
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67 | |
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68 | count -= c; |
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69 | cmpltd += c; |
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70 | blk++; |
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71 | ofs = 0; |
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72 | } |
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73 | return cmpltd; |
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74 | } |
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75 | |
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76 | /* _fat_block_write -- |
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77 | * This function write 'count' bytes to device filesystem is mounted on, |
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78 | * starts at 'start+offset' position where 'start' computed in sectors |
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79 | * and 'offset' is offset inside sector (writing may cross sectors |
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80 | * boundary; in this case assumed we want to write sequential sector(s)) |
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81 | * |
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82 | * PARAMETERS: |
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83 | * mt_entry - mount table entry |
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84 | * start - sector num to start read from |
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85 | * offset - offset inside sector 'start' |
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86 | * count - count of bytes to write |
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87 | * buff - buffer provided by user |
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88 | * |
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89 | * RETURNS: |
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90 | * bytes written on success, or -1 if error occured |
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91 | * and errno set appropriately |
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92 | */ |
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93 | ssize_t |
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94 | _fat_block_write( |
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95 | rtems_filesystem_mount_table_entry_t *mt_entry, |
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96 | unsigned32 start, |
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97 | unsigned32 offset, |
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98 | unsigned32 count, |
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99 | const void *buff) |
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100 | { |
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101 | int rc = RC_OK; |
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102 | fat_fs_info_t *fs_info = mt_entry->fs_info; |
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103 | ssize_t cmpltd = 0; |
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104 | unsigned32 blk = start; |
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105 | unsigned32 ofs = offset; |
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106 | bdbuf_buffer *block = NULL; |
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107 | unsigned32 c = 0; |
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108 | |
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109 | while(count > 0) |
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110 | { |
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111 | c = MIN(count, (fs_info->vol.bps - ofs)); |
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112 | |
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113 | if (c == fs_info->vol.bps) |
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114 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_GET, &block); |
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115 | else |
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116 | rc = fat_buf_access(fs_info, blk, FAT_OP_TYPE_READ, &block); |
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117 | if (rc != RC_OK) |
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118 | return rc; |
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119 | |
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120 | memcpy((block->buffer + ofs), (buff + cmpltd), c); |
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121 | |
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122 | fat_buf_mark_modified(fs_info); |
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123 | |
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124 | count -= c; |
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125 | cmpltd +=c; |
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126 | blk++; |
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127 | ofs = 0; |
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128 | } |
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129 | return cmpltd; |
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130 | } |
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131 | |
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132 | |
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133 | |
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134 | |
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135 | /* fat_cluster_read -- |
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136 | * wrapper for reading a whole cluster at once |
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137 | * |
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138 | * PARAMETERS: |
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139 | * mt_entry - mount table entry |
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140 | * cln - number of cluster to read |
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141 | * buff - buffer provided by user |
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142 | * |
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143 | * RETURNS: |
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144 | * bytes read on success, or -1 if error occured |
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145 | * and errno set appropriately |
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146 | */ |
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147 | ssize_t |
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148 | fat_cluster_read( |
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149 | rtems_filesystem_mount_table_entry_t *mt_entry, |
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150 | unsigned32 cln, |
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151 | void *buff |
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152 | ) |
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153 | { |
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154 | fat_fs_info_t *fs_info = mt_entry->fs_info; |
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155 | unsigned32 fsec = 0; |
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156 | |
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157 | fsec = fat_cluster_num_to_sector_num(mt_entry, cln); |
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158 | |
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159 | return _fat_block_read(mt_entry, fsec, 0, |
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160 | fs_info->vol.spc << fs_info->vol.sec_log2, buff); |
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161 | } |
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162 | |
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163 | /* fat_cluster_write -- |
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164 | * wrapper for writting a whole cluster at once |
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165 | * |
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166 | * PARAMETERS: |
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167 | * mt_entry - mount table entry |
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168 | * cln - number of cluster to write |
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169 | * buff - buffer provided by user |
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170 | * |
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171 | * RETURNS: |
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172 | * bytes written on success, or -1 if error occured |
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173 | * and errno set appropriately |
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174 | */ |
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175 | ssize_t |
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176 | fat_cluster_write( |
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177 | rtems_filesystem_mount_table_entry_t *mt_entry, |
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178 | unsigned32 cln, |
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179 | const void *buff |
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180 | ) |
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181 | { |
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182 | fat_fs_info_t *fs_info = mt_entry->fs_info; |
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183 | unsigned32 fsec = 0; |
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184 | |
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185 | fsec = fat_cluster_num_to_sector_num(mt_entry, cln); |
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186 | |
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187 | return _fat_block_write(mt_entry, fsec, 0, |
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188 | fs_info->vol.spc << fs_info->vol.sec_log2, buff); |
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189 | } |
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190 | |
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191 | /* fat_init_volume_info -- |
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192 | * Get inforamtion about volume on which filesystem is mounted on |
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193 | * |
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194 | * PARAMETERS: |
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195 | * mt_entry - mount table entry |
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196 | * |
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197 | * RETURNS: |
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198 | * RC_OK on success, or -1 if error occured |
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199 | * and errno set appropriately |
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200 | */ |
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201 | int |
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202 | fat_init_volume_info(rtems_filesystem_mount_table_entry_t *mt_entry) |
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203 | { |
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204 | int rc = RC_OK; |
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205 | fat_fs_info_t *fs_info = mt_entry->fs_info; |
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206 | register fat_vol_t *vol = &fs_info->vol; |
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207 | unsigned32 data_secs = 0; |
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208 | char boot_rec[FAT_MAX_BPB_SIZE]; |
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209 | char fs_info_sector[FAT_USEFUL_INFO_SIZE]; |
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210 | ssize_t ret = 0; |
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211 | int fd; |
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212 | struct stat stat_buf; |
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213 | int i = 0; |
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214 | |
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215 | rc = stat(mt_entry->dev, &stat_buf); |
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216 | if (rc == -1) |
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217 | return rc; |
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218 | |
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219 | /* rtmes feature: no block devices, all are character devices */ |
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220 | if (!S_ISCHR(stat_buf.st_mode)) |
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221 | set_errno_and_return_minus_one(ENOTBLK); |
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222 | |
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223 | /* check that device is registred as block device and lock it */ |
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224 | vol->dd = rtems_disk_lookup(stat_buf.st_dev); |
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225 | if (vol->dd == NULL) |
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226 | set_errno_and_return_minus_one(ENOTBLK); |
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227 | |
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228 | vol->dev = stat_buf.st_dev; |
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229 | |
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230 | fd = open(mt_entry->dev, O_RDONLY); |
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231 | if (fd == -1) |
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232 | { |
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233 | rtems_disk_release(vol->dd); |
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234 | return -1; |
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235 | } |
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236 | |
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237 | ret = read(fd, (void *)boot_rec, FAT_MAX_BPB_SIZE); |
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238 | if ( ret != FAT_MAX_BPB_SIZE ) |
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239 | { |
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240 | close(fd); |
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241 | rtems_disk_release(vol->dd); |
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242 | set_errno_and_return_minus_one( EIO ); |
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243 | } |
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244 | close(fd); |
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245 | |
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246 | vol->bps = FAT_BR_BYTES_PER_SECTOR(boot_rec); |
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247 | |
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248 | if ( (vol->bps != 512) && |
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249 | (vol->bps != 1024) && |
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250 | (vol->bps != 2048) && |
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251 | (vol->bps != 4096)) |
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252 | { |
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253 | rtems_disk_release(vol->dd); |
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254 | set_errno_and_return_minus_one( EINVAL ); |
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255 | } |
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256 | |
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257 | for (vol->sec_mul = 0, i = (vol->bps >> FAT_SECTOR512_BITS); (i & 1) == 0; |
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258 | i >>= 1, vol->sec_mul++); |
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259 | for (vol->sec_log2 = 0, i = vol->bps; (i & 1) == 0; |
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260 | i >>= 1, vol->sec_log2++); |
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261 | |
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262 | vol->spc = FAT_BR_SECTORS_PER_CLUSTER(boot_rec); |
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263 | /* |
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264 | * "sectors per cluster" of zero is invalid |
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265 | * (and would hang the following loop) |
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266 | */ |
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267 | if (vol->spc == 0) |
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268 | { |
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269 | rtems_disk_release(vol->dd); |
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270 | set_errno_and_return_minus_one(EINVAL); |
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271 | } |
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272 | |
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273 | for (vol->spc_log2 = 0, i = vol->spc; (i & 1) == 0; |
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274 | i >>= 1, vol->spc_log2++); |
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275 | |
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276 | /* |
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277 | * "bytes per cluster" value greater than 32K is invalid |
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278 | */ |
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279 | if ((vol->bpc = vol->bps << vol->spc_log2) > MS_BYTES_PER_CLUSTER_LIMIT) |
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280 | { |
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281 | rtems_disk_release(vol->dd); |
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282 | set_errno_and_return_minus_one(EINVAL); |
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283 | } |
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284 | |
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285 | for (vol->bpc_log2 = 0, i = vol->bpc; (i & 1) == 0; |
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286 | i >>= 1, vol->bpc_log2++); |
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287 | |
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288 | vol->fats = FAT_BR_FAT_NUM(boot_rec); |
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289 | vol->fat_loc = FAT_BR_RESERVED_SECTORS_NUM(boot_rec); |
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290 | |
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291 | vol->rdir_entrs = FAT_BR_FILES_PER_ROOT_DIR(boot_rec); |
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292 | |
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293 | /* calculate the count of sectors occupied by the root directory */ |
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294 | vol->rdir_secs = ((vol->rdir_entrs * FAT_DIRENTRY_SIZE) + (vol->bps - 1)) / |
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295 | vol->bps; |
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296 | |
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297 | vol->rdir_size = vol->rdir_secs << vol->sec_log2; |
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298 | |
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299 | if ( (FAT_BR_SECTORS_PER_FAT(boot_rec)) != 0) |
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300 | vol->fat_length = FAT_BR_SECTORS_PER_FAT(boot_rec); |
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301 | else |
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302 | vol->fat_length = FAT_BR_SECTORS_PER_FAT32(boot_rec); |
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303 | |
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304 | vol->data_fsec = vol->fat_loc + vol->fats * vol->fat_length + |
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305 | vol->rdir_secs; |
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306 | |
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307 | /* for FAT12/16 root dir starts at(sector) */ |
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308 | vol->rdir_loc = vol->fat_loc + vol->fats * vol->fat_length; |
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309 | |
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310 | if ( (FAT_BR_TOTAL_SECTORS_NUM16(boot_rec)) != 0) |
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311 | vol->tot_secs = FAT_BR_TOTAL_SECTORS_NUM16(boot_rec); |
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312 | else |
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313 | vol->tot_secs = FAT_BR_TOTAL_SECTORS_NUM32(boot_rec); |
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314 | |
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315 | data_secs = vol->tot_secs - vol->data_fsec; |
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316 | |
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317 | vol->data_cls = data_secs / vol->spc; |
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318 | |
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319 | /* determine FAT type at least */ |
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320 | if ( vol->data_cls < FAT_FAT12_MAX_CLN) |
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321 | { |
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322 | vol->type = FAT_FAT12; |
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323 | vol->mask = FAT_FAT12_MASK; |
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324 | vol->eoc_val = FAT_FAT12_EOC; |
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325 | } |
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326 | else |
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327 | { |
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328 | if ( vol->data_cls < FAT_FAT16_MAX_CLN) |
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329 | { |
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330 | vol->type = FAT_FAT16; |
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331 | vol->mask = FAT_FAT16_MASK; |
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332 | vol->eoc_val = FAT_FAT16_EOC; |
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333 | } |
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334 | else |
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335 | { |
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336 | vol->type = FAT_FAT32; |
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337 | vol->mask = FAT_FAT32_MASK; |
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338 | vol->eoc_val = FAT_FAT32_EOC; |
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339 | } |
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340 | } |
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341 | |
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342 | if (vol->type == FAT_FAT32) |
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343 | { |
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344 | vol->rdir_cl = FAT_BR_FAT32_ROOT_CLUSTER(boot_rec); |
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345 | |
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346 | vol->mirror = FAT_BR_EXT_FLAGS(boot_rec) & FAT_BR_EXT_FLAGS_MIRROR; |
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347 | if (vol->mirror) |
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348 | vol->afat = FAT_BR_EXT_FLAGS(boot_rec) & FAT_BR_EXT_FLAGS_FAT_NUM; |
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349 | else |
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350 | vol->afat = 0; |
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351 | |
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352 | vol->info_sec = FAT_BR_FAT32_FS_INFO_SECTOR(boot_rec); |
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353 | if( vol->info_sec == 0 ) |
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354 | { |
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355 | rtems_disk_release(vol->dd); |
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356 | set_errno_and_return_minus_one( EINVAL ); |
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357 | } |
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358 | else |
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359 | { |
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360 | ret = _fat_block_read(mt_entry, vol->info_sec , 0, |
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361 | FAT_FSI_LEADSIG_SIZE, fs_info_sector); |
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362 | if ( ret < 0 ) |
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363 | { |
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364 | rtems_disk_release(vol->dd); |
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365 | return -1; |
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366 | } |
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367 | |
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368 | if (FAT_FSINFO_LEAD_SIGNATURE(fs_info_sector) != |
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369 | FAT_FSINFO_LEAD_SIGNATURE_VALUE) |
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370 | { |
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371 | rtems_disk_release(vol->dd); |
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372 | set_errno_and_return_minus_one( EINVAL ); |
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373 | } |
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374 | else |
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375 | { |
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376 | ret = _fat_block_read(mt_entry, vol->info_sec , FAT_FSI_INFO, |
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377 | FAT_USEFUL_INFO_SIZE, fs_info_sector); |
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378 | if ( ret < 0 ) |
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379 | { |
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380 | rtems_disk_release(vol->dd); |
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381 | return -1; |
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382 | } |
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383 | |
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384 | vol->free_cls = FAT_FSINFO_FREE_CLUSTER_COUNT(fs_info_sector); |
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385 | vol->next_cl = FAT_FSINFO_NEXT_FREE_CLUSTER(fs_info_sector); |
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386 | rc = fat_fat32_update_fsinfo_sector(mt_entry, 0xFFFFFFFF, |
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387 | 0xFFFFFFFF); |
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388 | if ( rc != RC_OK ) |
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389 | { |
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390 | rtems_disk_release(vol->dd); |
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391 | return rc; |
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392 | } |
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393 | } |
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394 | } |
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395 | } |
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396 | else |
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397 | { |
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398 | vol->rdir_cl = 0; |
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399 | vol->mirror = 0; |
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400 | vol->afat = 0; |
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401 | vol->free_cls = 0xFFFFFFFF; |
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402 | vol->next_cl = 0xFFFFFFFF; |
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403 | } |
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404 | vol->afat_loc = vol->fat_loc + vol->fat_length * vol->afat; |
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405 | |
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406 | /* set up collection of fat-files fd */ |
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407 | fs_info->vhash = calloc(FAT_HASH_SIZE, sizeof(Chain_Control)); |
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408 | if ( fs_info->vhash == NULL ) |
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409 | { |
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410 | rtems_disk_release(vol->dd); |
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411 | set_errno_and_return_minus_one( ENOMEM ); |
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412 | } |
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413 | |
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414 | for (i = 0; i < FAT_HASH_SIZE; i++) |
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415 | _Chain_Initialize_empty(fs_info->vhash + i); |
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416 | |
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417 | fs_info->rhash = calloc(FAT_HASH_SIZE, sizeof(Chain_Control)); |
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418 | if ( fs_info->rhash == NULL ) |
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419 | { |
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420 | rtems_disk_release(vol->dd); |
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421 | free(fs_info->vhash); |
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422 | set_errno_and_return_minus_one( ENOMEM ); |
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423 | } |
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424 | for (i = 0; i < FAT_HASH_SIZE; i++) |
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425 | _Chain_Initialize_empty(fs_info->rhash + i); |
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426 | |
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427 | fs_info->uino_pool_size = FAT_UINO_POOL_INIT_SIZE; |
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428 | fs_info->uino_base = (vol->tot_secs << vol->sec_mul) << 4; |
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429 | fs_info->index = 0; |
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430 | fs_info->uino = (char *)calloc(fs_info->uino_pool_size, sizeof(char)); |
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431 | if ( fs_info->uino == NULL ) |
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432 | { |
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433 | rtems_disk_release(vol->dd); |
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434 | free(fs_info->vhash); |
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435 | free(fs_info->rhash); |
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436 | set_errno_and_return_minus_one( ENOMEM ); |
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437 | } |
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438 | fs_info->sec_buf = (char *)calloc(vol->bps, sizeof(char)); |
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439 | if (fs_info->sec_buf == NULL) |
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440 | { |
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441 | rtems_disk_release(vol->dd); |
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442 | free(fs_info->vhash); |
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443 | free(fs_info->rhash); |
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444 | free(fs_info->uino); |
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445 | set_errno_and_return_minus_one( ENOMEM ); |
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446 | } |
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447 | |
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448 | return RC_OK; |
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449 | } |
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450 | |
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451 | /* fat_shutdown_drive -- |
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452 | * Free all allocated resources and synchronize all necessary data |
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453 | * |
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454 | * PARAMETERS: |
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455 | * mt_entry - mount table entry |
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456 | * |
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457 | * RETURNS: |
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458 | * RC_OK on success, or -1 if error occured |
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459 | * and errno set appropriately |
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460 | */ |
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461 | int |
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462 | fat_shutdown_drive(rtems_filesystem_mount_table_entry_t *mt_entry) |
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463 | { |
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464 | int rc = RC_OK; |
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465 | fat_fs_info_t *fs_info = mt_entry->fs_info; |
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466 | int i = 0; |
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467 | |
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468 | if (fs_info->vol.type & FAT_FAT32) |
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469 | { |
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470 | rc = fat_fat32_update_fsinfo_sector(mt_entry, fs_info->vol.free_cls, |
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471 | fs_info->vol.next_cl); |
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472 | if ( rc != RC_OK ) |
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473 | rc = -1; |
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474 | } |
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475 | |
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476 | fat_buf_release(fs_info); |
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477 | |
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478 | if (rtems_bdbuf_syncdev(fs_info->vol.dev) != RTEMS_SUCCESSFUL) |
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479 | rc = -1; |
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480 | |
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481 | for (i = 0; i < FAT_HASH_SIZE; i++) |
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482 | { |
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483 | Chain_Node *node = NULL; |
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484 | Chain_Control *the_chain = fs_info->vhash + i; |
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485 | |
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486 | while ( (node = _Chain_Get(the_chain)) != NULL ) |
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487 | free(node); |
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488 | } |
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489 | |
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490 | for (i = 0; i < FAT_HASH_SIZE; i++) |
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491 | { |
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492 | Chain_Node *node = NULL; |
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493 | Chain_Control *the_chain = fs_info->rhash + i; |
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494 | |
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495 | while ( (node = _Chain_Get(the_chain)) != NULL ) |
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496 | free(node); |
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497 | } |
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498 | |
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499 | free(fs_info->vhash); |
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500 | free(fs_info->rhash); |
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501 | |
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502 | free(fs_info->uino); |
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503 | free(fs_info->sec_buf); |
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504 | rtems_disk_release(fs_info->vol.dd); |
---|
505 | |
---|
506 | if (rc) |
---|
507 | errno = EIO; |
---|
508 | return rc; |
---|
509 | } |
---|
510 | |
---|
511 | /* fat_init_clusters_chain -- |
---|
512 | * Zeroing contents of all clusters in the chain |
---|
513 | * |
---|
514 | * PARAMETERS: |
---|
515 | * mt_entry - mount table entry |
---|
516 | * start_cluster_num - num of first cluster in the chain |
---|
517 | * |
---|
518 | * RETURNS: |
---|
519 | * RC_OK on success, or -1 if error occured |
---|
520 | * and errno set appropriately |
---|
521 | */ |
---|
522 | int |
---|
523 | fat_init_clusters_chain( |
---|
524 | rtems_filesystem_mount_table_entry_t *mt_entry, |
---|
525 | unsigned32 start_cln |
---|
526 | ) |
---|
527 | { |
---|
528 | int rc = RC_OK; |
---|
529 | ssize_t ret = 0; |
---|
530 | register fat_fs_info_t *fs_info = mt_entry->fs_info; |
---|
531 | unsigned32 cur_cln = start_cln; |
---|
532 | char *buf; |
---|
533 | |
---|
534 | buf = calloc(fs_info->vol.bpc, sizeof(char)); |
---|
535 | if ( buf == NULL ) |
---|
536 | set_errno_and_return_minus_one( EIO ); |
---|
537 | |
---|
538 | while ((cur_cln & fs_info->vol.mask) < fs_info->vol.eoc_val) |
---|
539 | { |
---|
540 | ret = fat_cluster_write(mt_entry, cur_cln, buf); |
---|
541 | if ( ret == -1 ) |
---|
542 | { |
---|
543 | free(buf); |
---|
544 | return -1; |
---|
545 | } |
---|
546 | |
---|
547 | rc = fat_get_fat_cluster(mt_entry, cur_cln, &cur_cln); |
---|
548 | if ( rc != RC_OK ) |
---|
549 | { |
---|
550 | free(buf); |
---|
551 | return rc; |
---|
552 | } |
---|
553 | |
---|
554 | } |
---|
555 | free(buf); |
---|
556 | return rc; |
---|
557 | } |
---|
558 | |
---|
559 | #define FAT_UNIQ_INO_BASE 0x0FFFFF00 |
---|
560 | |
---|
561 | #define FAT_UNIQ_INO_IS_BUSY(index, arr) \ |
---|
562 | (((arr)[((index)>>3)]>>((index) & (8-1))) & 0x01) |
---|
563 | |
---|
564 | #define FAT_SET_UNIQ_INO_BUSY(index, arr) \ |
---|
565 | ((arr)[((index)>>3)] |= (0x01<<((index) & (8-1)))) |
---|
566 | |
---|
567 | #define FAT_SET_UNIQ_INO_FREE(index, arr) \ |
---|
568 | ((arr)[((index)>>3)] &= (~(0x01<<((index) & (8-1))))) |
---|
569 | |
---|
570 | /* fat_get_unique_ino -- |
---|
571 | * Allocate unique ino from unique ino pool |
---|
572 | * |
---|
573 | * PARAMETERS: |
---|
574 | * mt_entry - mount table entry |
---|
575 | * |
---|
576 | * RETURNS: |
---|
577 | * unique inode number on success, or 0 if there is no free unique inode |
---|
578 | * number in the pool |
---|
579 | * |
---|
580 | * ATTENTION: |
---|
581 | * 0 means FAILED !!! |
---|
582 | * |
---|
583 | */ |
---|
584 | unsigned32 |
---|
585 | fat_get_unique_ino(rtems_filesystem_mount_table_entry_t *mt_entry) |
---|
586 | { |
---|
587 | register fat_fs_info_t *fs_info = mt_entry->fs_info; |
---|
588 | unsigned32 j = 0; |
---|
589 | rtems_boolean resrc_unsuff = FALSE; |
---|
590 | |
---|
591 | while (!resrc_unsuff) |
---|
592 | { |
---|
593 | for (j = 0; j < fs_info->uino_pool_size; j++) |
---|
594 | { |
---|
595 | if (!FAT_UNIQ_INO_IS_BUSY(fs_info->index, fs_info->uino)) |
---|
596 | { |
---|
597 | FAT_SET_UNIQ_INO_BUSY(fs_info->index, fs_info->uino); |
---|
598 | return (fs_info->uino_base + fs_info->index); |
---|
599 | } |
---|
600 | fs_info->index++; |
---|
601 | if (fs_info->index >= fs_info->uino_pool_size) |
---|
602 | fs_info->index = 0; |
---|
603 | } |
---|
604 | |
---|
605 | if ((fs_info->uino_pool_size << 1) < (0x0FFFFFFF - fs_info->uino_base)) |
---|
606 | { |
---|
607 | fs_info->uino_pool_size <<= 1; |
---|
608 | fs_info->uino = realloc(fs_info->uino, fs_info->uino_pool_size); |
---|
609 | if (fs_info->uino != NULL) |
---|
610 | fs_info->index = fs_info->uino_pool_size; |
---|
611 | else |
---|
612 | resrc_unsuff = TRUE; |
---|
613 | } |
---|
614 | else |
---|
615 | resrc_unsuff = TRUE; |
---|
616 | } |
---|
617 | return 0; |
---|
618 | } |
---|
619 | |
---|
620 | /* fat_free_unique_ino -- |
---|
621 | * Return unique ino to unique ino pool |
---|
622 | * |
---|
623 | * PARAMETERS: |
---|
624 | * mt_entry - mount table entry |
---|
625 | * ino - inode number to free |
---|
626 | * |
---|
627 | * RETURNS: |
---|
628 | * None |
---|
629 | */ |
---|
630 | void |
---|
631 | fat_free_unique_ino( |
---|
632 | rtems_filesystem_mount_table_entry_t *mt_entry, |
---|
633 | unsigned32 ino |
---|
634 | ) |
---|
635 | { |
---|
636 | fat_fs_info_t *fs_info = mt_entry->fs_info; |
---|
637 | |
---|
638 | FAT_SET_UNIQ_INO_FREE((ino - fs_info->uino_base), fs_info->uino); |
---|
639 | } |
---|
640 | |
---|
641 | /* fat_ino_is_unique -- |
---|
642 | * Test whether ino is from unique ino pool |
---|
643 | * |
---|
644 | * PARAMETERS: |
---|
645 | * mt_entry - mount table entry |
---|
646 | * ino - ino to be tested |
---|
647 | * |
---|
648 | * RETURNS: |
---|
649 | * TRUE if ino is allocated from unique ino pool, FALSE otherwise |
---|
650 | */ |
---|
651 | inline rtems_boolean |
---|
652 | fat_ino_is_unique( |
---|
653 | rtems_filesystem_mount_table_entry_t *mt_entry, |
---|
654 | unsigned32 ino |
---|
655 | ) |
---|
656 | { |
---|
657 | fat_fs_info_t *fs_info = mt_entry->fs_info; |
---|
658 | |
---|
659 | return (ino >= fs_info->uino_base); |
---|
660 | } |
---|
661 | |
---|
662 | /* fat_fat32_update_fsinfo_sector -- |
---|
663 | * Synchronize fsinfo sector for FAT32 volumes |
---|
664 | * |
---|
665 | * PARAMETERS: |
---|
666 | * mt_entry - mount table entry |
---|
667 | * free_count - count of free clusters |
---|
668 | * next_free - the next free cluster num |
---|
669 | * |
---|
670 | * RETURNS: |
---|
671 | * RC_OK on success, or -1 if error occured (errno set appropriately) |
---|
672 | */ |
---|
673 | int |
---|
674 | fat_fat32_update_fsinfo_sector( |
---|
675 | rtems_filesystem_mount_table_entry_t *mt_entry, |
---|
676 | unsigned32 free_count, |
---|
677 | unsigned32 next_free |
---|
678 | ) |
---|
679 | { |
---|
680 | ssize_t ret1 = 0, ret2 = 0; |
---|
681 | register fat_fs_info_t *fs_info = mt_entry->fs_info; |
---|
682 | unsigned32 le_free_count = 0; |
---|
683 | unsigned32 le_next_free = 0; |
---|
684 | |
---|
685 | le_free_count = CT_LE_L(free_count); |
---|
686 | le_next_free = CT_LE_L(next_free); |
---|
687 | |
---|
688 | ret1 = _fat_block_write(mt_entry, |
---|
689 | fs_info->vol.info_sec, |
---|
690 | FAT_FSINFO_FREE_CLUSTER_COUNT_OFFSET, |
---|
691 | 4, |
---|
692 | (char *)(&le_free_count)); |
---|
693 | |
---|
694 | ret2 = _fat_block_write(mt_entry, |
---|
695 | fs_info->vol.info_sec, |
---|
696 | FAT_FSINFO_NEXT_FREE_CLUSTER_OFFSET, |
---|
697 | 4, |
---|
698 | (char *)(&le_next_free)); |
---|
699 | |
---|
700 | if ( (ret1 < 0) || (ret2 < 0) ) |
---|
701 | return -1; |
---|
702 | |
---|
703 | return RC_OK; |
---|
704 | } |
---|
705 | |
---|