[2/2] exfat: zero out atime subsecond timestamp

Commit Message

Eric Sandeen April 16, 2020, 1:12 a.m. UTC

There doesn't seem to be a sub-second granularity for exfat atime,
so tv_nsec needs to be zeroed out every time atime gets set.

Signed-off-by: Eric Sandeen <[e-mail]>
---

I know doing it brute-force this way is terrible, so this may not be the
right approach but it highlights the issue at least.

Patch

diff --git a/fs/exfat/file.c b/fs/exfat/file.c
index 483f683757aa..3527c69b7038 100644
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -273,6 +273,7 @@  int exfat_getattr(const struct path *path, struct kstat *stat,
 	struct exfat_inode_info *ei = EXFAT_I(inode);
 
 	generic_fillattr(inode, stat);
+	stat->atime.tv_nsec = 0;
 	stat->result_mask |= STATX_BTIME;
 	stat->btime.tv_sec = ei->i_crtime.tv_sec;
 	stat->btime.tv_nsec = ei->i_crtime.tv_nsec;
@@ -339,6 +340,7 @@  int exfat_setattr(struct dentry *dentry, struct iattr *attr)
 	}
 
 	setattr_copy(inode, attr);
+	inode->i_atime.tv_nsec = 0;
 	mark_inode_dirty(inode);
 
 out:
diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c
index 14a3300848f6..101e169a9a4b 100644
--- a/fs/exfat/misc.c
+++ b/fs/exfat/misc.c
@@ -88,7 +88,8 @@  void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
 	if (time_ms) {
 		ts->tv_sec += time_ms / 100;
 		ts->tv_nsec = (time_ms % 100) * 10 * NSEC_PER_MSEC;
-	}
+	} else
+		ts->tv_nsec = 0;
 
 	if (tz & EXFAT_TZ_VALID)
 		/* Adjust timezone to UTC0. */
diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
index a8681d91f569..64d1b8ea4dfd 100644
--- a/fs/exfat/namei.c
+++ b/fs/exfat/namei.c
@@ -595,6 +595,7 @@  static int exfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 	inode_inc_iversion(inode);
 	inode->i_mtime = inode->i_atime = inode->i_ctime =
 		EXFAT_I(inode)->i_crtime = current_time(inode);
+	inode->i_atime.tv_nsec = 0;
 	/* timestamp is already written, so mark_inode_dirty() is unneeded. */
 
 	d_instantiate(dentry, inode);
@@ -854,6 +855,7 @@  static int exfat_unlink(struct inode *dir, struct dentry *dentry)
 
 	inode_inc_iversion(dir);
 	dir->i_mtime = dir->i_atime = current_time(dir);
+	inode->i_atime.tv_nsec = 0;
 	if (IS_DIRSYNC(dir))
 		exfat_sync_inode(dir);
 	else
@@ -861,6 +863,7 @@  static int exfat_unlink(struct inode *dir, struct dentry *dentry)
 
 	clear_nlink(inode);
 	inode->i_mtime = inode->i_atime = current_time(inode);
+	inode->i_atime.tv_nsec = 0;
 	exfat_unhash_inode(inode);
 	exfat_d_version_set(dentry, inode_query_iversion(dir));
 unlock:
@@ -903,6 +906,7 @@  static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	inode_inc_iversion(inode);
 	inode->i_mtime = inode->i_atime = inode->i_ctime =
 		EXFAT_I(inode)->i_crtime = current_time(inode);
+	inode->i_atime.tv_nsec = 0;
 	/* timestamp is already written, so mark_inode_dirty() is unneeded. */
 
 	d_instantiate(dentry, inode);
@@ -1019,6 +1023,7 @@  static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
 
 	inode_inc_iversion(dir);
 	dir->i_mtime = dir->i_atime = current_time(dir);
+	inode->i_atime.tv_nsec = 0;
 	if (IS_DIRSYNC(dir))
 		exfat_sync_inode(dir);
 	else
@@ -1027,6 +1032,7 @@  static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
 
 	clear_nlink(inode);
 	inode->i_mtime = inode->i_atime = current_time(inode);
+	inode->i_atime.tv_nsec = 0;
 	exfat_unhash_inode(inode);
 	exfat_d_version_set(dentry, inode_query_iversion(dir));
 unlock:
@@ -1387,6 +1393,7 @@  static int exfat_rename(struct inode *old_dir, struct dentry *old_dentry,
 	inode_inc_iversion(new_dir);
 	new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
 		EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
+	new_dir->i_atime.tv_nsec = 0;
 	if (IS_DIRSYNC(new_dir))
 		exfat_sync_inode(new_dir);
 	else
diff --git a/fs/exfat/super.c b/fs/exfat/super.c
index 16ed202ef527..4f21bf8b550d 100644
--- a/fs/exfat/super.c
+++ b/fs/exfat/super.c
@@ -351,6 +351,7 @@  static int exfat_read_root(struct inode *inode)
 	exfat_save_attr(inode, ATTR_SUBDIR);
 	inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime =
 		current_time(inode);
+	inode->i_atime.tv_nsec = 0;
 	exfat_cache_init_inode(inode);
 	return 0;
 }