Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/fat/misc.c |
| 3 | * |
| 4 | * Written 1992,1993 by Werner Almesberger |
| 5 | * 22/11/2000 - Fixed fat_date_unix2dos for dates earlier than 01/01/1980 |
| 6 | * and date_dos2unix for date==0 by Igor Zhbanov(bsg@uniyar.ac.ru) |
| 7 | */ |
| 8 | |
OGAWA Hirofumi | 9e975da | 2008-11-06 12:53:46 -0800 | [diff] [blame] | 9 | #include "fat.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | |
| 11 | /* |
Denis Karpov | 85c7859 | 2009-06-04 02:34:22 +0900 | [diff] [blame] | 12 | * fat_fs_error reports a file system problem that might indicate fa data |
| 13 | * corruption/inconsistency. Depending on 'errors' mount option the |
| 14 | * panic() is called, or error message is printed FAT and nothing is done, |
| 15 | * or filesystem is remounted read-only (default behavior). |
| 16 | * In case the file system is remounted read-only, it can be made writable |
| 17 | * again by remounting it. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | */ |
Alexey Fisher | 2c8a5ff | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 19 | void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | { |
Alexey Fisher | 2c8a5ff | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 21 | struct fat_mount_options *opts = &MSDOS_SB(sb)->options; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | va_list args; |
Alexey Fisher | 2c8a5ff | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 23 | struct va_format vaf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | |
OGAWA Hirofumi | aaa04b4 | 2010-05-24 14:33:12 -0700 | [diff] [blame] | 25 | if (report) { |
OGAWA Hirofumi | aaa04b4 | 2010-05-24 14:33:12 -0700 | [diff] [blame] | 26 | va_start(args, fmt); |
Alexey Fisher | 2c8a5ff | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 27 | vaf.fmt = fmt; |
| 28 | vaf.va = &args; |
Gu Zheng | e68e96d | 2013-07-03 15:08:08 -0700 | [diff] [blame] | 29 | fat_msg(sb, KERN_ERR, "error, %pV", &vaf); |
OGAWA Hirofumi | aaa04b4 | 2010-05-24 14:33:12 -0700 | [diff] [blame] | 30 | va_end(args); |
OGAWA Hirofumi | aaa04b4 | 2010-05-24 14:33:12 -0700 | [diff] [blame] | 31 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
Denis Karpov | 85c7859 | 2009-06-04 02:34:22 +0900 | [diff] [blame] | 33 | if (opts->errors == FAT_ERRORS_PANIC) |
Alexey Fisher | 2c8a5ff | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 34 | panic("FAT-fs (%s): fs panic from previous error\n", sb->s_id); |
David Howells | bc98a42 | 2017-07-17 08:45:34 +0100 | [diff] [blame] | 35 | else if (opts->errors == FAT_ERRORS_RO && !sb_rdonly(sb)) { |
Linus Torvalds | 1751e8a | 2017-11-27 13:05:09 -0800 | [diff] [blame] | 36 | sb->s_flags |= SB_RDONLY; |
Gu Zheng | e68e96d | 2013-07-03 15:08:08 -0700 | [diff] [blame] | 37 | fat_msg(sb, KERN_ERR, "Filesystem has been set read-only"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | } |
| 39 | } |
OGAWA Hirofumi | aaa04b4 | 2010-05-24 14:33:12 -0700 | [diff] [blame] | 40 | EXPORT_SYMBOL_GPL(__fat_fs_error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
Alexey Fisher | 81ac21d | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 42 | /** |
| 43 | * fat_msg() - print preformated FAT specific messages. Every thing what is |
| 44 | * not fat_fs_error() should be fat_msg(). |
| 45 | */ |
| 46 | void fat_msg(struct super_block *sb, const char *level, const char *fmt, ...) |
| 47 | { |
| 48 | struct va_format vaf; |
| 49 | va_list args; |
| 50 | |
| 51 | va_start(args, fmt); |
| 52 | vaf.fmt = fmt; |
| 53 | vaf.va = &args; |
| 54 | printk("%sFAT-fs (%s): %pV\n", level, sb->s_id, &vaf); |
| 55 | va_end(args); |
| 56 | } |
| 57 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | /* Flushes the number of free clusters on FAT32 */ |
| 59 | /* XXX: Need to write one per FSINFO block. Currently only writes 1 */ |
OGAWA Hirofumi | ed248b2 | 2009-09-20 01:31:58 +0900 | [diff] [blame] | 60 | int fat_clusters_flush(struct super_block *sb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | { |
| 62 | struct msdos_sb_info *sbi = MSDOS_SB(sb); |
| 63 | struct buffer_head *bh; |
| 64 | struct fat_boot_fsinfo *fsinfo; |
| 65 | |
| 66 | if (sbi->fat_bits != 32) |
OGAWA Hirofumi | ed248b2 | 2009-09-20 01:31:58 +0900 | [diff] [blame] | 67 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | |
| 69 | bh = sb_bread(sb, sbi->fsinfo_sector); |
| 70 | if (bh == NULL) { |
Alexey Fisher | 869f58c | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 71 | fat_msg(sb, KERN_ERR, "bread failed in fat_clusters_flush"); |
OGAWA Hirofumi | ed248b2 | 2009-09-20 01:31:58 +0900 | [diff] [blame] | 72 | return -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | } |
| 74 | |
| 75 | fsinfo = (struct fat_boot_fsinfo *)bh->b_data; |
| 76 | /* Sanity check */ |
| 77 | if (!IS_FSINFO(fsinfo)) { |
Alexey Fisher | 869f58c | 2011-04-12 21:08:38 +0900 | [diff] [blame] | 78 | fat_msg(sb, KERN_ERR, "Invalid FSINFO signature: " |
| 79 | "0x%08x, 0x%08x (sector = %lu)", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | le32_to_cpu(fsinfo->signature1), |
| 81 | le32_to_cpu(fsinfo->signature2), |
| 82 | sbi->fsinfo_sector); |
| 83 | } else { |
| 84 | if (sbi->free_clusters != -1) |
| 85 | fsinfo->free_clusters = cpu_to_le32(sbi->free_clusters); |
| 86 | if (sbi->prev_free != -1) |
| 87 | fsinfo->next_cluster = cpu_to_le32(sbi->prev_free); |
| 88 | mark_buffer_dirty(bh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | } |
| 90 | brelse(bh); |
OGAWA Hirofumi | ed248b2 | 2009-09-20 01:31:58 +0900 | [diff] [blame] | 91 | |
| 92 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | } |
| 94 | |
| 95 | /* |
| 96 | * fat_chain_add() adds a new cluster to the chain of clusters represented |
| 97 | * by inode. |
| 98 | */ |
| 99 | int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster) |
| 100 | { |
| 101 | struct super_block *sb = inode->i_sb; |
| 102 | struct msdos_sb_info *sbi = MSDOS_SB(sb); |
| 103 | int ret, new_fclus, last; |
| 104 | |
| 105 | /* |
| 106 | * We must locate the last cluster of the file to add this new |
| 107 | * one (new_dclus) to the end of the link list (the FAT). |
| 108 | */ |
| 109 | last = new_fclus = 0; |
| 110 | if (MSDOS_I(inode)->i_start) { |
| 111 | int fclus, dclus; |
| 112 | |
| 113 | ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus); |
| 114 | if (ret < 0) |
| 115 | return ret; |
| 116 | new_fclus = fclus + 1; |
| 117 | last = dclus; |
| 118 | } |
| 119 | |
| 120 | /* add new one to the last of the cluster chain */ |
| 121 | if (last) { |
| 122 | struct fat_entry fatent; |
| 123 | |
| 124 | fatent_init(&fatent); |
| 125 | ret = fat_ent_read(inode, &fatent, last); |
| 126 | if (ret >= 0) { |
| 127 | int wait = inode_needs_sync(inode); |
| 128 | ret = fat_ent_write(inode, &fatent, new_dclus, wait); |
| 129 | fatent_brelse(&fatent); |
| 130 | } |
| 131 | if (ret < 0) |
| 132 | return ret; |
Ravishankar N | c39540c | 2012-12-20 15:05:46 -0800 | [diff] [blame] | 133 | /* |
| 134 | * FIXME:Although we can add this cache, fat_cache_add() is |
| 135 | * assuming to be called after linear search with fat_cache_id. |
| 136 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | // fat_cache_add(inode, new_fclus, new_dclus); |
| 138 | } else { |
| 139 | MSDOS_I(inode)->i_start = new_dclus; |
| 140 | MSDOS_I(inode)->i_logstart = new_dclus; |
| 141 | /* |
Jan Kara | 2f3d675 | 2009-08-17 17:00:02 +0200 | [diff] [blame] | 142 | * Since generic_write_sync() synchronizes regular files later, |
| 143 | * we sync here only directories. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | */ |
| 145 | if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode)) { |
| 146 | ret = fat_sync_inode(inode); |
| 147 | if (ret) |
| 148 | return ret; |
| 149 | } else |
| 150 | mark_inode_dirty(inode); |
| 151 | } |
| 152 | if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) { |
Denis Karpov | 85c7859 | 2009-06-04 02:34:22 +0900 | [diff] [blame] | 153 | fat_fs_error(sb, "clusters badly computed (%d != %llu)", |
OGAWA Hirofumi | c330293 | 2008-11-06 12:53:58 -0800 | [diff] [blame] | 154 | new_fclus, |
| 155 | (llu)(inode->i_blocks >> (sbi->cluster_bits - 9))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | fat_cache_inval_inode(inode); |
| 157 | } |
| 158 | inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9); |
| 159 | |
| 160 | return 0; |
| 161 | } |
| 162 | |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 163 | /* |
| 164 | * The epoch of FAT timestamp is 1980. |
| 165 | * : bits : value |
| 166 | * date: 0 - 4: day (1 - 31) |
| 167 | * date: 5 - 8: month (1 - 12) |
| 168 | * date: 9 - 15: year (0 - 127) from 1980 |
| 169 | * time: 0 - 4: sec (0 - 29) 2sec counts |
| 170 | * time: 5 - 10: min (0 - 59) |
| 171 | * time: 11 - 15: hour (0 - 23) |
| 172 | */ |
| 173 | #define SECS_PER_MIN 60 |
| 174 | #define SECS_PER_HOUR (60 * 60) |
| 175 | #define SECS_PER_DAY (SECS_PER_HOUR * 24) |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 176 | /* days between 1.1.70 and 1.1.80 (2 leap days) */ |
| 177 | #define DAYS_DELTA (365 * 10 + 2) |
| 178 | /* 120 (2100 - 1980) isn't leap year */ |
| 179 | #define YEAR_2100 120 |
| 180 | #define IS_LEAP_YEAR(y) (!((y) & 3) && (y) != YEAR_2100) |
| 181 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | /* Linear day numbers of the respective 1sts in non-leap years. */ |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 183 | static time_t days_in_year[] = { |
| 184 | /* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */ |
| 185 | 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 186 | }; |
| 187 | |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 188 | /* Convert a FAT time/date pair to a UNIX date (seconds since 1 1 70). */ |
| 189 | void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts, |
| 190 | __le16 __time, __le16 __date, u8 time_cs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | { |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 192 | u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date); |
| 193 | time_t second, day, leap_day, month, year; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 195 | year = date >> 9; |
| 196 | month = max(1, (date >> 5) & 0xf); |
| 197 | day = max(1, date & 0x1f) - 1; |
| 198 | |
| 199 | leap_day = (year + 3) / 4; |
| 200 | if (year > YEAR_2100) /* 2100 isn't leap year */ |
| 201 | leap_day--; |
| 202 | if (IS_LEAP_YEAR(year) && month > 2) |
| 203 | leap_day++; |
| 204 | |
| 205 | second = (time & 0x1f) << 1; |
| 206 | second += ((time >> 5) & 0x3f) * SECS_PER_MIN; |
| 207 | second += (time >> 11) * SECS_PER_HOUR; |
| 208 | second += (year * 365 + leap_day |
| 209 | + days_in_year[month] + day |
| 210 | + DAYS_DELTA) * SECS_PER_DAY; |
| 211 | |
Jan Kara | 58156c8 | 2012-12-17 16:02:58 -0800 | [diff] [blame] | 212 | if (!sbi->options.tz_set) |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 213 | second += sys_tz.tz_minuteswest * SECS_PER_MIN; |
Jan Kara | 58156c8 | 2012-12-17 16:02:58 -0800 | [diff] [blame] | 214 | else |
| 215 | second -= sbi->options.time_offset * SECS_PER_MIN; |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 216 | |
| 217 | if (time_cs) { |
| 218 | ts->tv_sec = second + (time_cs / 100); |
| 219 | ts->tv_nsec = (time_cs % 100) * 10000000; |
| 220 | } else { |
| 221 | ts->tv_sec = second; |
| 222 | ts->tv_nsec = 0; |
| 223 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | } |
| 225 | |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 226 | /* Convert linear UNIX date to a FAT time/date pair. */ |
| 227 | void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts, |
| 228 | __le16 *time, __le16 *date, u8 *time_cs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | { |
Zhaolei | 1d81a18 | 2009-12-15 16:46:57 -0800 | [diff] [blame] | 230 | struct tm tm; |
Jan Kara | 58156c8 | 2012-12-17 16:02:58 -0800 | [diff] [blame] | 231 | time_to_tm(ts->tv_sec, |
| 232 | (sbi->options.tz_set ? sbi->options.time_offset : |
| 233 | -sys_tz.tz_minuteswest) * SECS_PER_MIN, &tm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | |
Zhaolei | 1d81a18 | 2009-12-15 16:46:57 -0800 | [diff] [blame] | 235 | /* FAT can only support year between 1980 to 2107 */ |
| 236 | if (tm.tm_year < 1980 - 1900) { |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 237 | *time = 0; |
| 238 | *date = cpu_to_le16((0 << 9) | (1 << 5) | 1); |
| 239 | if (time_cs) |
| 240 | *time_cs = 0; |
| 241 | return; |
| 242 | } |
Zhaolei | 1d81a18 | 2009-12-15 16:46:57 -0800 | [diff] [blame] | 243 | if (tm.tm_year > 2107 - 1900) { |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 244 | *time = cpu_to_le16((23 << 11) | (59 << 5) | 29); |
| 245 | *date = cpu_to_le16((127 << 9) | (12 << 5) | 31); |
| 246 | if (time_cs) |
| 247 | *time_cs = 199; |
| 248 | return; |
| 249 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 250 | |
Zhaolei | 1d81a18 | 2009-12-15 16:46:57 -0800 | [diff] [blame] | 251 | /* from 1900 -> from 1980 */ |
| 252 | tm.tm_year -= 80; |
| 253 | /* 0~11 -> 1~12 */ |
| 254 | tm.tm_mon++; |
| 255 | /* 0~59 -> 0~29(2sec counts) */ |
| 256 | tm.tm_sec >>= 1; |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 257 | |
Zhaolei | 1d81a18 | 2009-12-15 16:46:57 -0800 | [diff] [blame] | 258 | *time = cpu_to_le16(tm.tm_hour << 11 | tm.tm_min << 5 | tm.tm_sec); |
| 259 | *date = cpu_to_le16(tm.tm_year << 9 | tm.tm_mon << 5 | tm.tm_mday); |
OGAWA Hirofumi | 7decd1c | 2008-11-06 12:53:47 -0800 | [diff] [blame] | 260 | if (time_cs) |
| 261 | *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000; |
| 262 | } |
| 263 | EXPORT_SYMBOL_GPL(fat_time_unix2fat); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | |
| 265 | int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs) |
| 266 | { |
OGAWA Hirofumi | 5b00226 | 2006-02-03 03:04:42 -0800 | [diff] [blame] | 267 | int i, err = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | |
Christoph Hellwig | 9cb569d | 2010-08-11 17:06:24 +0200 | [diff] [blame] | 269 | for (i = 0; i < nr_bhs; i++) |
Mike Christie | 2a222ca | 2016-06-05 14:31:43 -0500 | [diff] [blame] | 270 | write_dirty_buffer(bhs[i], 0); |
Christoph Hellwig | 9cb569d | 2010-08-11 17:06:24 +0200 | [diff] [blame] | 271 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | for (i = 0; i < nr_bhs; i++) { |
| 273 | wait_on_buffer(bhs[i]); |
Christoph Hellwig | 0edd55f | 2010-08-18 05:29:23 -0400 | [diff] [blame] | 274 | if (!err && !buffer_uptodate(bhs[i])) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | err = -EIO; |
| 276 | } |
| 277 | return err; |
| 278 | } |