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>

1 files changed, 6 insertions, 11 deletions

diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 16a832c37d66..efb8c40c9d27 100644
--- a/fs/fat/namei_msdos.c
+++ b/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;