2020-04-16 13:11 GMT+09:00, Eric Sandeen <sandeen@xxxxxxxxxxx>:
Hi Eric,
> exfat atimes are restricted to only 2s granularity so after
> we set an atime, round it down to the nearest 2s and set the
> sub-second component of the timestamp to 0.
Is there any reason why only atime is truncated with 2s granularity ?
Thanks.
>
> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxxx>
> ---
>
> V2: don't just zero tv_nsec, must also round down tv_sec I think.
>
> diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
> index 67d4e46fb810..d67fb8a6f770 100644
> --- a/fs/exfat/exfat_fs.h
> +++ b/fs/exfat/exfat_fs.h
> @@ -507,6 +507,7 @@ void exfat_msg(struct super_block *sb, const char *lv,
> const char *fmt, ...)
> __printf(3, 4) __cold;
> void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64
> *ts,
> u8 tz, __le16 time, __le16 date, u8 time_ms);
> +void exfat_truncate_atime(struct timespec64 *ts);
> void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64
> *ts,
> u8 *tz, __le16 *time, __le16 *date, u8 *time_ms);
> unsigned short exfat_calc_chksum_2byte(void *data, int len,
> diff --git a/fs/exfat/file.c b/fs/exfat/file.c
> index 483f683757aa..4f76764165cf 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);
> + exfat_truncate_atime(&stat->atime);
> 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);
> + exfat_truncate_atime(&inode->i_atime);
> mark_inode_dirty(inode);
>
> out:
> diff --git a/fs/exfat/misc.c b/fs/exfat/misc.c
> index 14a3300848f6..c8b33278d474 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
> + exfat_truncate_atime(ts);
>
> if (tz & EXFAT_TZ_VALID)
> /* Adjust timezone to UTC0. */
> @@ -124,6 +125,13 @@ void exfat_set_entry_time(struct exfat_sb_info *sbi,
> struct timespec64 *ts,
> *tz = EXFAT_TZ_VALID;
> }
>
> +/* atime has only a 2-second resolution */
> +void exfat_truncate_atime(struct timespec64 *ts)
> +{
> + ts->tv_sec = round_down(ts->tv_sec, 2);
> + ts->tv_nsec = 0;
> +}
> +
> unsigned short exfat_calc_chksum_2byte(void *data, int len,
> unsigned short chksum, int type)
> {
> diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
> index a8681d91f569..b72d782568b8 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);
> + exfat_truncate_atime(&inode->i_atime);
> /* 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);
> + exfat_truncate_atime(&dir->i_atime);
> 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);
> + exfat_truncate_atime(&inode->i_atime);
> 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);
> + exfat_truncate_atime(&inode->i_atime);
> /* 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);
> + exfat_truncate_atime(&dir->i_atime);
> 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);
> + exfat_truncate_atime(&inode->i_atime);
> 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);
> + exfat_truncate_atime(&new_dir->i_atime);
> 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..aed62cafb0da 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);
> + exfat_truncate_atime(&inode->i_atime);
> exfat_cache_init_inode(inode);
> return 0;
> }
>
>
