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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/fs/fat/misc.c
4 *
5 * Written 1992,1993 by Werner Almesberger
6 * 22/11/2000 - Fixed fat_date_unix2dos for dates earlier than 01/01/1980
7 * and date_dos2unix for date==0 by Igor Zhbanov(bsg@uniyar.ac.ru)
8 */
9
10#include "fat.h"
11#include <linux/iversion.h>
12
13/*
14 * fat_fs_error reports a file system problem that might indicate fa data
15 * corruption/inconsistency. Depending on 'errors' mount option the
16 * panic() is called, or error message is printed FAT and nothing is done,
17 * or filesystem is remounted read-only (default behavior).
18 * In case the file system is remounted read-only, it can be made writable
19 * again by remounting it.
20 */
21void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
22{
23 struct fat_mount_options *opts = &MSDOS_SB(sb)->options;
24 va_list args;
25 struct va_format vaf;
26
27 if (report) {
28 va_start(args, fmt);
29 vaf.fmt = fmt;
30 vaf.va = &args;
31 fat_msg(sb, KERN_ERR, "error, %pV", &vaf);
32 va_end(args);
33 }
34
35 if (opts->errors == FAT_ERRORS_PANIC)
36 panic("FAT-fs (%s): fs panic from previous error\n", sb->s_id);
37 else if (opts->errors == FAT_ERRORS_RO && !sb_rdonly(sb)) {
38 sb->s_flags |= SB_RDONLY;
39 fat_msg(sb, KERN_ERR, "Filesystem has been set read-only");
40 }
41}
42EXPORT_SYMBOL_GPL(__fat_fs_error);
43
44/**
45 * _fat_msg() - Print a preformatted FAT message based on a superblock.
46 * @sb: A pointer to a &struct super_block
47 * @level: A Kernel printk level constant
48 * @fmt: The printf-style format string to print.
49 *
50 * Everything that is not fat_fs_error() should be fat_msg().
51 *
52 * fat_msg() wraps _fat_msg() for printk indexing.
53 */
54void _fat_msg(struct super_block *sb, const char *level, const char *fmt, ...)
55{
56 struct va_format vaf;
57 va_list args;
58
59 va_start(args, fmt);
60 vaf.fmt = fmt;
61 vaf.va = &args;
62 _printk(FAT_PRINTK_PREFIX "%pV\n", level, sb->s_id, &vaf);
63 va_end(args);
64}
65
66/* Flushes the number of free clusters on FAT32 */
67/* XXX: Need to write one per FSINFO block. Currently only writes 1 */
68int fat_clusters_flush(struct super_block *sb)
69{
70 struct msdos_sb_info *sbi = MSDOS_SB(sb);
71 struct buffer_head *bh;
72 struct fat_boot_fsinfo *fsinfo;
73
74 if (!is_fat32(sbi))
75 return 0;
76
77 bh = sb_bread(sb, sbi->fsinfo_sector);
78 if (bh == NULL) {
79 fat_msg(sb, KERN_ERR, "bread failed in fat_clusters_flush");
80 return -EIO;
81 }
82
83 fsinfo = (struct fat_boot_fsinfo *)bh->b_data;
84 /* Sanity check */
85 if (!IS_FSINFO(fsinfo)) {
86 fat_msg(sb, KERN_ERR, "Invalid FSINFO signature: "
87 "0x%08x, 0x%08x (sector = %lu)",
88 le32_to_cpu(fsinfo->signature1),
89 le32_to_cpu(fsinfo->signature2),
90 sbi->fsinfo_sector);
91 } else {
92 if (sbi->free_clusters != -1)
93 fsinfo->free_clusters = cpu_to_le32(sbi->free_clusters);
94 if (sbi->prev_free != -1)
95 fsinfo->next_cluster = cpu_to_le32(sbi->prev_free);
96 mark_buffer_dirty(bh);
97 }
98 brelse(bh);
99
100 return 0;
101}
102
103/*
104 * fat_chain_add() adds a new cluster to the chain of clusters represented
105 * by inode.
106 */
107int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
108{
109 struct super_block *sb = inode->i_sb;
110 struct msdos_sb_info *sbi = MSDOS_SB(sb);
111 int ret, new_fclus, last;
112
113 /*
114 * We must locate the last cluster of the file to add this new
115 * one (new_dclus) to the end of the link list (the FAT).
116 */
117 last = new_fclus = 0;
118 if (MSDOS_I(inode)->i_start) {
119 int fclus, dclus;
120
121 ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
122 if (ret < 0)
123 return ret;
124 new_fclus = fclus + 1;
125 last = dclus;
126 }
127
128 /* add new one to the last of the cluster chain */
129 if (last) {
130 struct fat_entry fatent;
131
132 fatent_init(&fatent);
133 ret = fat_ent_read(inode, &fatent, last);
134 if (ret >= 0) {
135 int wait = inode_needs_sync(inode);
136 ret = fat_ent_write(inode, &fatent, new_dclus, wait);
137 fatent_brelse(&fatent);
138 }
139 if (ret < 0)
140 return ret;
141 /*
142 * FIXME:Although we can add this cache, fat_cache_add() is
143 * assuming to be called after linear search with fat_cache_id.
144 */
145// fat_cache_add(inode, new_fclus, new_dclus);
146 } else {
147 MSDOS_I(inode)->i_start = new_dclus;
148 MSDOS_I(inode)->i_logstart = new_dclus;
149 /*
150 * Since generic_write_sync() synchronizes regular files later,
151 * we sync here only directories.
152 */
153 if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode)) {
154 ret = fat_sync_inode(inode);
155 if (ret)
156 return ret;
157 } else
158 mark_inode_dirty(inode);
159 }
160 if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) {
161 fat_fs_error(sb, "clusters badly computed (%d != %llu)",
162 new_fclus,
163 (llu)(inode->i_blocks >> (sbi->cluster_bits - 9)));
164 fat_cache_inval_inode(inode);
165 }
166 inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9);
167
168 return 0;
169}
170
171/*
172 * The epoch of FAT timestamp is 1980.
173 * : bits : value
174 * date: 0 - 4: day (1 - 31)
175 * date: 5 - 8: month (1 - 12)
176 * date: 9 - 15: year (0 - 127) from 1980
177 * time: 0 - 4: sec (0 - 29) 2sec counts
178 * time: 5 - 10: min (0 - 59)
179 * time: 11 - 15: hour (0 - 23)
180 */
181#define SECS_PER_MIN 60
182#define SECS_PER_HOUR (60 * 60)
183#define SECS_PER_DAY (SECS_PER_HOUR * 24)
184/* days between 1.1.70 and 1.1.80 (2 leap days) */
185#define DAYS_DELTA (365 * 10 + 2)
186/* 120 (2100 - 1980) isn't leap year */
187#define YEAR_2100 120
188#define IS_LEAP_YEAR(y) (!((y) & 3) && (y) != YEAR_2100)
189
190/* Linear day numbers of the respective 1sts in non-leap years. */
191static long days_in_year[] = {
192 /* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */
193 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0,
194};
195
196static inline int fat_tz_offset(const struct msdos_sb_info *sbi)
197{
198 return (sbi->options.tz_set ?
199 -sbi->options.time_offset :
200 sys_tz.tz_minuteswest) * SECS_PER_MIN;
201}
202
203/* Convert a FAT time/date pair to a UNIX date (seconds since 1 1 70). */
204void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec64 *ts,
205 __le16 __time, __le16 __date, u8 time_cs)
206{
207 u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
208 time64_t second;
209 long day, leap_day, month, year;
210
211 year = date >> 9;
212 month = max(1, (date >> 5) & 0xf);
213 day = max(1, date & 0x1f) - 1;
214
215 leap_day = (year + 3) / 4;
216 if (year > YEAR_2100) /* 2100 isn't leap year */
217 leap_day--;
218 if (IS_LEAP_YEAR(year) && month > 2)
219 leap_day++;
220
221 second = (time & 0x1f) << 1;
222 second += ((time >> 5) & 0x3f) * SECS_PER_MIN;
223 second += (time >> 11) * SECS_PER_HOUR;
224 second += (time64_t)(year * 365 + leap_day
225 + days_in_year[month] + day
226 + DAYS_DELTA) * SECS_PER_DAY;
227
228 second += fat_tz_offset(sbi);
229
230 if (time_cs) {
231 ts->tv_sec = second + (time_cs / 100);
232 ts->tv_nsec = (time_cs % 100) * 10000000;
233 } else {
234 ts->tv_sec = second;
235 ts->tv_nsec = 0;
236 }
237}
238
239/* Export fat_time_fat2unix() for the fat_test KUnit tests. */
240EXPORT_SYMBOL_GPL(fat_time_fat2unix);
241
242/* Convert linear UNIX date to a FAT time/date pair. */
243void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec64 *ts,
244 __le16 *time, __le16 *date, u8 *time_cs)
245{
246 struct tm tm;
247 time64_to_tm(ts->tv_sec, -fat_tz_offset(sbi), &tm);
248
249 /* FAT can only support year between 1980 to 2107 */
250 if (tm.tm_year < 1980 - 1900) {
251 *time = 0;
252 *date = cpu_to_le16((0 << 9) | (1 << 5) | 1);
253 if (time_cs)
254 *time_cs = 0;
255 return;
256 }
257 if (tm.tm_year > 2107 - 1900) {
258 *time = cpu_to_le16((23 << 11) | (59 << 5) | 29);
259 *date = cpu_to_le16((127 << 9) | (12 << 5) | 31);
260 if (time_cs)
261 *time_cs = 199;
262 return;
263 }
264
265 /* from 1900 -> from 1980 */
266 tm.tm_year -= 80;
267 /* 0~11 -> 1~12 */
268 tm.tm_mon++;
269 /* 0~59 -> 0~29(2sec counts) */
270 tm.tm_sec >>= 1;
271
272 *time = cpu_to_le16(tm.tm_hour << 11 | tm.tm_min << 5 | tm.tm_sec);
273 *date = cpu_to_le16(tm.tm_year << 9 | tm.tm_mon << 5 | tm.tm_mday);
274 if (time_cs)
275 *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000;
276}
277EXPORT_SYMBOL_GPL(fat_time_unix2fat);
278
279static inline struct timespec64 fat_timespec64_trunc_2secs(struct timespec64 ts)
280{
281 return (struct timespec64){ ts.tv_sec & ~1ULL, 0 };
282}
283
284/*
285 * truncate atime to 24 hour granularity (00:00:00 in local timezone)
286 */
287struct timespec64 fat_truncate_atime(const struct msdos_sb_info *sbi,
288 const struct timespec64 *ts)
289{
290 /* to localtime */
291 time64_t seconds = ts->tv_sec - fat_tz_offset(sbi);
292 s32 remainder;
293
294 div_s64_rem(seconds, SECS_PER_DAY, &remainder);
295 /* to day boundary, and back to unix time */
296 seconds = seconds + fat_tz_offset(sbi) - remainder;
297
298 return (struct timespec64){ seconds, 0 };
299}
300
301/*
302 * truncate mtime to 2 second granularity
303 */
304struct timespec64 fat_truncate_mtime(const struct msdos_sb_info *sbi,
305 const struct timespec64 *ts)
306{
307 return fat_timespec64_trunc_2secs(*ts);
308}
309
310/*
311 * truncate the various times with appropriate granularity:
312 * all times in root node are always 0
313 */
314int fat_truncate_time(struct inode *inode, struct timespec64 *now, int flags)
315{
316 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
317 struct timespec64 ts;
318
319 if (inode->i_ino == MSDOS_ROOT_INO)
320 return 0;
321
322 if (now == NULL) {
323 now = &ts;
324 ts = current_time(inode);
325 }
326
327 if (flags & S_ATIME)
328 inode->i_atime = fat_truncate_atime(sbi, now);
329 /*
330 * ctime and mtime share the same on-disk field, and should be
331 * identical in memory. all mtime updates will be applied to ctime,
332 * but ctime updates are ignored.
333 */
334 if (flags & S_MTIME)
335 inode->i_mtime = inode->i_ctime = fat_truncate_mtime(sbi, now);
336
337 return 0;
338}
339EXPORT_SYMBOL_GPL(fat_truncate_time);
340
341int fat_update_time(struct inode *inode, struct timespec64 *now, int flags)
342{
343 int dirty_flags = 0;
344
345 if (inode->i_ino == MSDOS_ROOT_INO)
346 return 0;
347
348 if (flags & (S_ATIME | S_CTIME | S_MTIME)) {
349 fat_truncate_time(inode, now, flags);
350 if (inode->i_sb->s_flags & SB_LAZYTIME)
351 dirty_flags |= I_DIRTY_TIME;
352 else
353 dirty_flags |= I_DIRTY_SYNC;
354 }
355
356 if ((flags & S_VERSION) && inode_maybe_inc_iversion(inode, false))
357 dirty_flags |= I_DIRTY_SYNC;
358
359 __mark_inode_dirty(inode, dirty_flags);
360 return 0;
361}
362EXPORT_SYMBOL_GPL(fat_update_time);
363
364int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
365{
366 int i, err = 0;
367
368 for (i = 0; i < nr_bhs; i++)
369 write_dirty_buffer(bhs[i], 0);
370
371 for (i = 0; i < nr_bhs; i++) {
372 wait_on_buffer(bhs[i]);
373 if (!err && !buffer_uptodate(bhs[i]))
374 err = -EIO;
375 }
376 return err;
377}
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
9#include "fat.h"
10
11/*
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.
18 */
19void __fat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
20{
21 struct fat_mount_options *opts = &MSDOS_SB(sb)->options;
22 va_list args;
23 struct va_format vaf;
24
25 if (report) {
26 va_start(args, fmt);
27 vaf.fmt = fmt;
28 vaf.va = &args;
29 fat_msg(sb, KERN_ERR, "error, %pV", &vaf);
30 va_end(args);
31 }
32
33 if (opts->errors == FAT_ERRORS_PANIC)
34 panic("FAT-fs (%s): fs panic from previous error\n", sb->s_id);
35 else if (opts->errors == FAT_ERRORS_RO && !(sb->s_flags & MS_RDONLY)) {
36 sb->s_flags |= MS_RDONLY;
37 fat_msg(sb, KERN_ERR, "Filesystem has been set read-only");
38 }
39}
40EXPORT_SYMBOL_GPL(__fat_fs_error);
41
42/**
43 * fat_msg() - print preformated FAT specific messages. Every thing what is
44 * not fat_fs_error() should be fat_msg().
45 */
46void 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
58/* Flushes the number of free clusters on FAT32 */
59/* XXX: Need to write one per FSINFO block. Currently only writes 1 */
60int fat_clusters_flush(struct super_block *sb)
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)
67 return 0;
68
69 bh = sb_bread(sb, sbi->fsinfo_sector);
70 if (bh == NULL) {
71 fat_msg(sb, KERN_ERR, "bread failed in fat_clusters_flush");
72 return -EIO;
73 }
74
75 fsinfo = (struct fat_boot_fsinfo *)bh->b_data;
76 /* Sanity check */
77 if (!IS_FSINFO(fsinfo)) {
78 fat_msg(sb, KERN_ERR, "Invalid FSINFO signature: "
79 "0x%08x, 0x%08x (sector = %lu)",
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);
89 }
90 brelse(bh);
91
92 return 0;
93}
94
95/*
96 * fat_chain_add() adds a new cluster to the chain of clusters represented
97 * by inode.
98 */
99int 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;
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 */
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 /*
142 * Since generic_write_sync() synchronizes regular files later,
143 * we sync here only directories.
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))) {
153 fat_fs_error(sb, "clusters badly computed (%d != %llu)",
154 new_fclus,
155 (llu)(inode->i_blocks >> (sbi->cluster_bits - 9)));
156 fat_cache_inval_inode(inode);
157 }
158 inode->i_blocks += nr_cluster << (sbi->cluster_bits - 9);
159
160 return 0;
161}
162
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)
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
182/* Linear day numbers of the respective 1sts in non-leap years. */
183static 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,
186};
187
188/* Convert a FAT time/date pair to a UNIX date (seconds since 1 1 70). */
189void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
190 __le16 __time, __le16 __date, u8 time_cs)
191{
192 u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
193 time_t second, day, leap_day, month, year;
194
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
212 if (!sbi->options.tz_set)
213 second += sys_tz.tz_minuteswest * SECS_PER_MIN;
214 else
215 second -= sbi->options.time_offset * SECS_PER_MIN;
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 }
224}
225
226/* Convert linear UNIX date to a FAT time/date pair. */
227void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
228 __le16 *time, __le16 *date, u8 *time_cs)
229{
230 struct tm tm;
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);
234
235 /* FAT can only support year between 1980 to 2107 */
236 if (tm.tm_year < 1980 - 1900) {
237 *time = 0;
238 *date = cpu_to_le16((0 << 9) | (1 << 5) | 1);
239 if (time_cs)
240 *time_cs = 0;
241 return;
242 }
243 if (tm.tm_year > 2107 - 1900) {
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 }
250
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;
257
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);
260 if (time_cs)
261 *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000;
262}
263EXPORT_SYMBOL_GPL(fat_time_unix2fat);
264
265int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
266{
267 int i, err = 0;
268
269 for (i = 0; i < nr_bhs; i++)
270 write_dirty_buffer(bhs[i], 0);
271
272 for (i = 0; i < nr_bhs; i++) {
273 wait_on_buffer(bhs[i]);
274 if (!err && !buffer_uptodate(bhs[i]))
275 err = -EIO;
276 }
277 return err;
278}