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, 7 insertions, 13 deletions

diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 9a5469120caa..82cd1e69cbdf 100644
--- a/fs/fat/namei_vfat.c
+++ b/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;