summaryrefslogtreecommitdiffstats
path: root/fs/fat
diff options
context:
space:
mode:
Diffstat (limited to 'fs/fat')
-rw-r--r--fs/fat/dir.c6
-rw-r--r--fs/fat/fat.h7
-rw-r--r--fs/fat/inode.c34
-rw-r--r--fs/fat/misc.c148
-rw-r--r--fs/fat/namei_msdos.c2
-rw-r--r--fs/fat/namei_vfat.c5
6 files changed, 130 insertions, 72 deletions
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index 08b23ad25f1c..a601c6d45bc0 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -1089,6 +1089,7 @@ int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
struct msdos_dir_entry *de;
sector_t blknr;
__le16 date, time;
+ u8 time_cs;
int err, cluster;
err = fat_alloc_clusters(dir, &cluster, 1);
@@ -1102,7 +1103,7 @@ int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
goto error_free;
}
- fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc);
+ fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
de = (struct msdos_dir_entry *)bhs[0]->b_data;
/* filling the new directory slots ("." and ".." entries) */
@@ -1112,13 +1113,14 @@ int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
de[0].lcase = de[1].lcase = 0;
de[0].time = de[1].time = time;
de[0].date = de[1].date = date;
- de[0].ctime_cs = de[1].ctime_cs = 0;
if (sbi->options.isvfat) {
/* extra timestamps */
de[0].ctime = de[1].ctime = time;
+ de[0].ctime_cs = de[1].ctime_cs = time_cs;
de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
} else {
de[0].ctime = de[1].ctime = 0;
+ de[0].ctime_cs = de[1].ctime_cs = 0;
de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
}
de[0].start = cpu_to_le16(cluster);
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index 51f1c42ca5e3..a2a570f81719 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -263,9 +263,10 @@ extern int fat_flush_inodes(struct super_block *sb, struct inode *i1,
extern void fat_fs_panic(struct super_block *s, const char *fmt, ...);
extern void fat_clusters_flush(struct super_block *sb);
extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
-extern int date_dos2unix(unsigned short time, unsigned short date, int tz_utc);
-extern void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date,
- int tz_utc);
+extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
+ __le16 __time, __le16 __date, u8 time_cs);
+extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
+ __le16 *time, __le16 *date, u8 *time_cs);
extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs);
int fat_cache_init(void);
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 3921de2013a4..079d9d5e0d36 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -381,22 +381,12 @@ static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
MSDOS_I(inode)->i_attrs = de->attr & ATTR_UNUSED;
inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
& ~((loff_t)sbi->cluster_size - 1)) >> 9;
- inode->i_mtime.tv_sec =
- date_dos2unix(le16_to_cpu(de->time), le16_to_cpu(de->date),
- sbi->options.tz_utc);
- inode->i_mtime.tv_nsec = 0;
+
+ fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0);
if (sbi->options.isvfat) {
- int secs = de->ctime_cs / 100;
- int csecs = de->ctime_cs % 100;
- inode->i_ctime.tv_sec =
- date_dos2unix(le16_to_cpu(de->ctime),
- le16_to_cpu(de->cdate),
- sbi->options.tz_utc) + secs;
- inode->i_ctime.tv_nsec = csecs * 10000000;
- inode->i_atime.tv_sec =
- date_dos2unix(0, le16_to_cpu(de->adate),
- sbi->options.tz_utc);
- inode->i_atime.tv_nsec = 0;
+ fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime,
+ de->cdate, de->ctime_cs);
+ fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0);
} else
inode->i_ctime = inode->i_atime = inode->i_mtime;
@@ -591,16 +581,14 @@ retry:
raw_entry->attr = fat_attr(inode);
raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart);
raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16);
- fat_date_unix2dos(inode->i_mtime.tv_sec, &raw_entry->time,
- &raw_entry->date, sbi->options.tz_utc);
+ fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
+ &raw_entry->date, NULL);
if (sbi->options.isvfat) {
__le16 atime;
- fat_date_unix2dos(inode->i_ctime.tv_sec, &raw_entry->ctime,
- &raw_entry->cdate, sbi->options.tz_utc);
- fat_date_unix2dos(inode->i_atime.tv_sec, &atime,
- &raw_entry->adate, sbi->options.tz_utc);
- raw_entry->ctime_cs = (inode->i_ctime.tv_sec & 1) * 100 +
- inode->i_ctime.tv_nsec / 10000000;
+ fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime,
+ &raw_entry->cdate, &raw_entry->ctime_cs);
+ fat_time_unix2fat(sbi, &inode->i_atime, &atime,
+ &raw_entry->adate, NULL);
}
spin_unlock(&sbi->inode_hash_lock);
mark_buffer_dirty(bh);
diff --git a/fs/fat/misc.c b/fs/fat/misc.c
index 91ad9be18ff9..a191e79e66a9 100644
--- a/fs/fat/misc.c
+++ b/fs/fat/misc.c
@@ -135,65 +135,131 @@ int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
extern struct timezone sys_tz;
+/*
+ * The epoch of FAT timestamp is 1980.
+ * : bits : value
+ * date: 0 - 4: day (1 - 31)
+ * date: 5 - 8: month (1 - 12)
+ * date: 9 - 15: year (0 - 127) from 1980
+ * time: 0 - 4: sec (0 - 29) 2sec counts
+ * time: 5 - 10: min (0 - 59)
+ * time: 11 - 15: hour (0 - 23)
+ */
+#define SECS_PER_MIN 60
+#define SECS_PER_HOUR (60 * 60)
+#define SECS_PER_DAY (SECS_PER_HOUR * 24)
+#define UNIX_SECS_1980 315532800L
+#if BITS_PER_LONG == 64
+#define UNIX_SECS_2108 4354819200L
+#endif
+/* days between 1.1.70 and 1.1.80 (2 leap days) */
+#define DAYS_DELTA (365 * 10 + 2)
+/* 120 (2100 - 1980) isn't leap year */
+#define YEAR_2100 120
+#define IS_LEAP_YEAR(y) (!((y) & 3) && (y) != YEAR_2100)
+
/* Linear day numbers of the respective 1sts in non-leap years. */
-static int day_n[] = {
- /* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */
- 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0, 0
+static time_t days_in_year[] = {
+ /* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */
+ 0, 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 0, 0, 0,
};
-/* Convert a MS-DOS time/date pair to a UNIX date (seconds since 1 1 70). */
-int date_dos2unix(unsigned short time, unsigned short date, int tz_utc)
+/* Convert a FAT time/date pair to a UNIX date (seconds since 1 1 70). */
+void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
+ __le16 __time, __le16 __date, u8 time_cs)
{
- int month, year, secs;
+ u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
+ time_t second, day, leap_day, month, year;
- /*
- * first subtract and mask after that... Otherwise, if
- * date == 0, bad things happen
- */
- month = ((date >> 5) - 1) & 15;
- year = date >> 9;
- secs = (time & 31)*2+60*((time >> 5) & 63)+(time >> 11)*3600+86400*
- ((date & 31)-1+day_n[month]+(year/4)+year*365-((year & 3) == 0 &&
- month < 2 ? 1 : 0)+3653);
- /* days since 1.1.70 plus 80's leap day */
- if (!tz_utc)
- secs += sys_tz.tz_minuteswest*60;
- return secs;
+ year = date >> 9;
+ month = max(1, (date >> 5) & 0xf);
+ day = max(1, date & 0x1f) - 1;
+
+ leap_day = (year + 3) / 4;
+ if (year > YEAR_2100) /* 2100 isn't leap year */
+ leap_day--;
+ if (IS_LEAP_YEAR(year) && month > 2)
+ leap_day++;
+
+ second = (time & 0x1f) << 1;
+ second += ((time >> 5) & 0x3f) * SECS_PER_MIN;
+ second += (time >> 11) * SECS_PER_HOUR;
+ second += (year * 365 + leap_day
+ + days_in_year[month] + day
+ + DAYS_DELTA) * SECS_PER_DAY;
+
+ if (!sbi->options.tz_utc)
+ second += sys_tz.tz_minuteswest * SECS_PER_MIN;
+
+ if (time_cs) {
+ ts->tv_sec = second + (time_cs / 100);
+ ts->tv_nsec = (time_cs % 100) * 10000000;
+ } else {
+ ts->tv_sec = second;
+ ts->tv_nsec = 0;
+ }
}
-/* Convert linear UNIX date to a MS-DOS time/date pair. */
-void fat_date_unix2dos(int unix_date, __le16 *time, __le16 *date, int tz_utc)
+/* Convert linear UNIX date to a FAT time/date pair. */
+void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
+ __le16 *time, __le16 *date, u8 *time_cs)
{
- int day, year, nl_day, month;
+ time_t second = ts->tv_sec;
+ time_t day, leap_day, month, year;
- if (!tz_utc)
- unix_date -= sys_tz.tz_minuteswest*60;
+ if (!sbi->options.tz_utc)
+ second -= sys_tz.tz_minuteswest * SECS_PER_MIN;
/* Jan 1 GMT 00:00:00 1980. But what about another time zone? */
- if (unix_date < 315532800)
- unix_date = 315532800;
-
- *time = cpu_to_le16((unix_date % 60)/2+(((unix_date/60) % 60) << 5)+
- (((unix_date/3600) % 24) << 11));
- day = unix_date/86400-3652;
- year = day/365;
- if ((year+3)/4+365*year > day)
+ if (second < UNIX_SECS_1980) {
+ *time = 0;
+ *date = cpu_to_le16((0 << 9) | (1 << 5) | 1);
+ if (time_cs)
+ *time_cs = 0;
+ return;
+ }
+#if BITS_PER_LONG == 64
+ if (second >= UNIX_SECS_2108) {
+ *time = cpu_to_le16((23 << 11) | (59 << 5) | 29);
+ *date = cpu_to_le16((127 << 9) | (12 << 5) | 31);
+ if (time_cs)
+ *time_cs = 199;
+ return;
+ }
+#endif
+
+ day = second / SECS_PER_DAY - DAYS_DELTA;
+ year = day / 365;
+ leap_day = (year + 3) / 4;
+ if (year > YEAR_2100) /* 2100 isn't leap year */
+ leap_day--;
+ if (year * 365 + leap_day > day)
year--;
- day -= (year+3)/4+365*year;
- if (day == 59 && !(year & 3)) {
- nl_day = day;
+ leap_day = (year + 3) / 4;
+ if (year > YEAR_2100) /* 2100 isn't leap year */
+ leap_day--;
+ day -= year * 365 + leap_day;
+
+ if (IS_LEAP_YEAR(year) && day == days_in_year[3]) {
month = 2;
} else {
- nl_day = (year & 3) || day <= 59 ? day : day-1;
- for (month = 0; month < 12; month++) {
- if (day_n[month] > nl_day)
+ if (IS_LEAP_YEAR(year) && day > days_in_year[3])
+ day--;
+ for (month = 1; month < 12; month++) {
+ if (days_in_year[month + 1] > day)
break;
}
}
- *date = cpu_to_le16(nl_day-day_n[month-1]+1+(month << 5)+(year << 9));
-}
+ day -= days_in_year[month];
-EXPORT_SYMBOL_GPL(fat_date_unix2dos);
+ *time = cpu_to_le16(((second / SECS_PER_HOUR) % 24) << 11
+ | ((second / SECS_PER_MIN) % 60) << 5
+ | (second % SECS_PER_MIN) >> 1);
+ *date = cpu_to_le16((year << 9) | (month << 5) | (day + 1));
+ if (time_cs)
+ *time_cs = (ts->tv_sec & 1) * 100 + ts->tv_nsec / 10000000;
+}
+EXPORT_SYMBOL_GPL(fat_time_unix2fat);
int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
{
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index c0a4d5cd99b2..e92e8158ebaf 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -247,7 +247,7 @@ static int msdos_add_entry(struct inode *dir, const unsigned char *name,
if (is_hid)
de.attr |= ATTR_HIDDEN;
de.lcase = 0;
- fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc);
+ fat_time_unix2fat(sbi, ts, &time, &date, NULL);
de.cdate = de.adate = 0;
de.ctime = 0;
de.ctime_cs = 0;
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index facf3bf0211a..1536bc3ca0f0 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -568,6 +568,7 @@ static int vfat_build_slots(struct inode *dir, const unsigned char *name,
unsigned char msdos_name[MSDOS_NAME];
wchar_t *uname;
__le16 time, date;
+ u8 time_cs;
int err, ulen, usize, i;
loff_t offset;
@@ -620,10 +621,10 @@ shortname:
memcpy(de->name, msdos_name, MSDOS_NAME);
de->attr = is_dir ? ATTR_DIR : ATTR_ARCH;
de->lcase = lcase;
- fat_date_unix2dos(ts->tv_sec, &time, &date, sbi->options.tz_utc);
+ fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
de->time = de->ctime = time;
de->date = de->cdate = de->adate = date;
- de->ctime_cs = 0;
+ de->ctime_cs = time_cs;
de->start = cpu_to_le16(cluster);
de->starthi = cpu_to_le16(cluster >> 16);
de->size = 0;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-17 12:09:28 +0000