fat: propagate 64-bit inode timestamps

Now that we pass down 64-bit timestamps from VFS, we just need to convert
that correctly into on-disk timestamps.  To make that work correctly, this
changes the last use of time_to_tm() in the kernel to time64_to_tm(),
which also lets use remove that deprecated interfaces.

Similarly, the time_t use in fat_time_fat2unix() truncates the timestamp
on the way in, which can be avoided by using types that are wide enough to
hold the intermediate values during the conversion.

[hirofumi@mail.parknet.co.jp: remove useless temporary variable, needless long long]
Link: http://lkml.kernel.org/r/20180619153646.3637529-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/fat/dir.c

@@ -1130,7 +1130,7 @@ error:
 	return err;
 }
 
-int fat_alloc_new_dir(struct inode *dir, struct timespec *ts)
+int fat_alloc_new_dir(struct inode *dir, struct timespec64 *ts)
 {
 	struct super_block *sb = dir->i_sb;
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);

fs/fat/fat.h

@@ -304,7 +304,7 @@ extern int fat_scan_logstart(struct inode *dir, int i_logstart,
 			     struct fat_slot_info *sinfo);
 extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
 				struct msdos_dir_entry **de);
-extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts);
+extern int fat_alloc_new_dir(struct inode *dir, struct timespec64 *ts);
 extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
 			   struct fat_slot_info *sinfo);
 extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo);
@@ -412,9 +412,9 @@ void fat_msg(struct super_block *sb, const char *level, const char *fmt, ...);
 	 } while (0)
 extern int fat_clusters_flush(struct super_block *sb);
 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
-extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
+extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec64 *ts,
 			      __le16 __time, __le16 __date, u8 time_cs);
-extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
+extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec64 *ts,
 			      __le16 *time, __le16 *date, u8 *time_cs);
 extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs);
 

fs/fat/inode.c

@@ -508,7 +508,6 @@ static int fat_validate_dir(struct inode *dir)
 /* doesn't deal with root inode */
 int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
 {
-	struct timespec ts;
 	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
 	int error;
 
@@ -559,14 +558,11 @@ int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
 	inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
 			   & ~((loff_t)sbi->cluster_size - 1)) >> 9;
 
-	fat_time_fat2unix(sbi, &ts, de->time, de->date, 0);
-	inode->i_mtime = timespec_to_timespec64(ts);
+	fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0);
 	if (sbi->options.isvfat) {
-		fat_time_fat2unix(sbi, &ts, de->ctime,
+		fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime,
 				  de->cdate, de->ctime_cs);
-		inode->i_ctime = timespec_to_timespec64(ts);
-		fat_time_fat2unix(sbi, &ts, 0, de->adate, 0);
-		inode->i_atime = timespec_to_timespec64(ts);
+		fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0);
 	} else
 		inode->i_ctime = inode->i_atime = inode->i_mtime;
 
@@ -843,7 +839,6 @@ static int fat_statfs(struct dentry *dentry, struct kstatfs *buf)
 
 static int __fat_write_inode(struct inode *inode, int wait)
 {
-	struct timespec ts;
 	struct super_block *sb = inode->i_sb;
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 	struct buffer_head *bh;
@@ -881,16 +876,13 @@ retry:
 		raw_entry->size = cpu_to_le32(inode->i_size);
 	raw_entry->attr = fat_make_attrs(inode);
 	fat_set_start(raw_entry, MSDOS_I(inode)->i_logstart);
-	ts = timespec64_to_timespec(inode->i_mtime);
-	fat_time_unix2fat(sbi, &ts, &raw_entry->time,
+	fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
 			  &raw_entry->date, NULL);
 	if (sbi->options.isvfat) {
 		__le16 atime;
-		ts = timespec64_to_timespec(inode->i_ctime);
-		fat_time_unix2fat(sbi, &ts, &raw_entry->ctime,
+		fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime,
 				  &raw_entry->cdate, &raw_entry->ctime_cs);
-		ts = timespec64_to_timespec(inode->i_atime);
-		fat_time_unix2fat(sbi, &ts, &atime,
+		fat_time_unix2fat(sbi, &inode->i_atime, &atime,
 				  &raw_entry->adate, NULL);
 	}
 	spin_unlock(&sbi->inode_hash_lock);

fs/fat/misc.c

@@ -180,17 +180,18 @@ int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
 #define IS_LEAP_YEAR(y)	(!((y) & 3) && (y) != YEAR_2100)
 
 /* Linear day numbers of the respective 1sts in non-leap years. */
-static time_t days_in_year[] = {
+static long 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 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,
+void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec64 *ts,
 		       __le16 __time, __le16 __date, u8 time_cs)
 {
 	u16 time = le16_to_cpu(__time), date = le16_to_cpu(__date);
-	time_t second, day, leap_day, month, year;
+	time64_t second;
+	long day, leap_day, month, year;
 
 	year  = date >> 9;
 	month = max(1, (date >> 5) & 0xf);
@@ -205,7 +206,7 @@ void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
 	second =  (time & 0x1f) << 1;
 	second += ((time >> 5) & 0x3f) * SECS_PER_MIN;
 	second += (time >> 11) * SECS_PER_HOUR;
-	second += (year * 365 + leap_day
+	second += (time64_t)(year * 365 + leap_day
 		   + days_in_year[month] + day
 		   + DAYS_DELTA) * SECS_PER_DAY;
 
@@ -224,11 +225,11 @@ void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
 }
 
 /* Convert linear UNIX date to a FAT time/date pair. */
-void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts,
+void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec64 *ts,
 		       __le16 *time, __le16 *date, u8 *time_cs)
 {
 	struct tm tm;
-	time_to_tm(ts->tv_sec,
+	time64_to_tm(ts->tv_sec,
 		   (sbi->options.tz_set ? sbi->options.time_offset :
 		   -sys_tz.tz_minuteswest) * SECS_PER_MIN, &tm);
 

fs/fat/namei_msdos.c

@@ -225,7 +225,7 @@ static struct dentry *msdos_lookup(struct inode *dir, struct dentry *dentry,
 /***** Creates a directory entry (name is already formatted). */
 static int msdos_add_entry(struct inode *dir, const unsigned char *name,
 			   int is_dir, int is_hid, int cluster,
-			   struct timespec *ts, struct fat_slot_info *sinfo)
+			   struct timespec64 *ts, struct fat_slot_info *sinfo)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
 	struct msdos_dir_entry de;
@@ -250,7 +250,7 @@ static int msdos_add_entry(struct inode *dir, const unsigned char *name,
 	if (err)
 		return err;
 
-	dir->i_ctime = dir->i_mtime = timespec_to_timespec64(*ts);
+	dir->i_ctime = dir->i_mtime = *ts;
 	if (IS_DIRSYNC(dir))
 		(void)fat_sync_inode(dir);
 	else
@@ -267,7 +267,6 @@ static int msdos_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	struct inode *inode = NULL;
 	struct fat_slot_info sinfo;
 	struct timespec64 ts;
-	struct timespec t;
 	unsigned char msdos_name[MSDOS_NAME];
 	int err, is_hid;
 
@@ -286,8 +285,7 @@ static int msdos_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	}
 
 	ts = current_time(dir);
-	t = timespec64_to_timespec(ts);
-	err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &t, &sinfo);
+	err = msdos_add_entry(dir, msdos_name, 0, is_hid, 0, &ts, &sinfo);
 	if (err)
 		goto out;
 	inode = fat_build_inode(sb, sinfo.de, sinfo.i_pos);
@@ -347,7 +345,6 @@ static int msdos_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	struct inode *inode;
 	unsigned char msdos_name[MSDOS_NAME];
 	struct timespec64 ts;
-	struct timespec t;
 	int err, is_hid, cluster;
 
 	mutex_lock(&MSDOS_SB(sb)->s_lock);
@@ -365,13 +362,12 @@ static int msdos_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	}
 
 	ts = current_time(dir);
-	t = timespec64_to_timespec(ts);
-	cluster = fat_alloc_new_dir(dir, &t);
+	cluster = fat_alloc_new_dir(dir, &ts);
 	if (cluster < 0) {
 		err = cluster;
 		goto out;
 	}
-	err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &t, &sinfo);
+	err = msdos_add_entry(dir, msdos_name, 1, is_hid, cluster, &ts, &sinfo);
 	if (err)
 		goto out_free;
 	inc_nlink(dir);
@@ -503,9 +499,8 @@ static int do_msdos_rename(struct inode *old_dir, unsigned char *old_name,
 		new_i_pos = MSDOS_I(new_inode)->i_pos;
 		fat_detach(new_inode);
 	} else {
-		struct timespec t = timespec64_to_timespec(ts);
 		err = msdos_add_entry(new_dir, new_name, is_dir, is_hid, 0,
-				      &t, &sinfo);
+				      &ts, &sinfo);
 		if (err)
 			goto out;
 		new_i_pos = sinfo.i_pos;

fs/fat/namei_vfat.c

@@ -577,7 +577,7 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname,
 
 static int vfat_build_slots(struct inode *dir, const unsigned char *name,
 			    int len, int is_dir, int cluster,
-			    struct timespec *ts,
+			    struct timespec64 *ts,
 			    struct msdos_dir_slot *slots, int *nr_slots)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(dir->i_sb);
@@ -653,7 +653,7 @@ out_free:
 }
 
 static int vfat_add_entry(struct inode *dir, const struct qstr *qname,
-			  int is_dir, int cluster, struct timespec *ts,
+			  int is_dir, int cluster, struct timespec64 *ts,
 			  struct fat_slot_info *sinfo)
 {
 	struct msdos_dir_slot *slots;
@@ -678,7 +678,7 @@ static int vfat_add_entry(struct inode *dir, const struct qstr *qname,
 		goto cleanup;
 
 	/* update timestamp */
-	dir->i_ctime = dir->i_mtime = dir->i_atime = timespec_to_timespec64(*ts);
+	dir->i_ctime = dir->i_mtime = dir->i_atime = *ts;
 	if (IS_DIRSYNC(dir))
 		(void)fat_sync_inode(dir);
 	else
@@ -762,14 +762,12 @@ static int vfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	struct inode *inode;
 	struct fat_slot_info sinfo;
 	struct timespec64 ts;
-	struct timespec t;
 	int err;
 
 	mutex_lock(&MSDOS_SB(sb)->s_lock);
 
 	ts = current_time(dir);
-	t = timespec64_to_timespec(ts);
-	err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &t, &sinfo);
+	err = vfat_add_entry(dir, &dentry->d_name, 0, 0, &ts, &sinfo);
 	if (err)
 		goto out;
 	inode_inc_iversion(dir);
@@ -853,19 +851,17 @@ static int vfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	struct inode *inode;
 	struct fat_slot_info sinfo;
 	struct timespec64 ts;
-	struct timespec t;
 	int err, cluster;
 
 	mutex_lock(&MSDOS_SB(sb)->s_lock);
 
 	ts = current_time(dir);
-	t = timespec64_to_timespec(ts);
-	cluster = fat_alloc_new_dir(dir, &t);
+	cluster = fat_alloc_new_dir(dir, &ts);
 	if (cluster < 0) {
 		err = cluster;
 		goto out;
 	}
-	err = vfat_add_entry(dir, &dentry->d_name, 1, cluster, &t, &sinfo);
+	err = vfat_add_entry(dir, &dentry->d_name, 1, cluster, &ts, &sinfo);
 	if (err)
 		goto out_free;
 	inode_inc_iversion(dir);
@@ -904,7 +900,6 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 	struct inode *old_inode, *new_inode;
 	struct fat_slot_info old_sinfo, sinfo;
 	struct timespec64 ts;
-	struct timespec t;
 	loff_t new_i_pos;
 	int err, is_dir, update_dotdot, corrupt = 0;
 	struct super_block *sb = old_dir->i_sb;
@@ -939,9 +934,8 @@ static int vfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 		new_i_pos = MSDOS_I(new_inode)->i_pos;
 		fat_detach(new_inode);
 	} else {
-		t = timespec64_to_timespec(ts);
 		err = vfat_add_entry(new_dir, &new_dentry->d_name, is_dir, 0,
-				     &t, &sinfo);
+				     &ts, &sinfo);
 		if (err)
 			goto out;
 		new_i_pos = sinfo.i_pos;