2020-04-18 22:03 GMT+09:00, Namjae Jeon <linkinjeon@xxxxxxxxxx>:
> 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 ?
I will directly update description more.
Sorry to bother you!
>
> 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;
>> }
>>
>>
>
