From 81df1ad40644b706a1cdbd28a1471f9f0c0ea3e8 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Tue, 21 Apr 2020 11:13:10 +0900 Subject: [Backport 81df1ad40644] exfat: truncate atimes to 2s granularity The timestamp for access_time has double seconds granularity(There is no 10msIncrement field for access_time unlike create/modify_time). exfat's 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. Signed-off-by: Eric Sandeen Signed-off-by: Namjae Jeon --- src/exfat_fs.h | 1 + src/file.c | 2 ++ src/misc.c | 14 +++++++++++++- src/namei.c | 7 +++++++ src/super.c | 1 + 5 files changed, 24 insertions(+), 1 deletion(-) diff --git a/src/exfat_fs.h b/src/exfat_fs.h index 67d4e46fb81003d0c367862ee986b37c80e7fa4e..d67fb8a6f770c28db8f1618c78fde493e2a4b965 100644 --- a/src/exfat_fs.h +++ b/src/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/src/file.c b/src/file.c index 483f683757aa87420ba347afd3c9db9e94b8a14d..4f76764165cf6f63a99c5e192ab33685e8e987b7 100644 --- a/src/file.c +++ b/src/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/src/misc.c b/src/misc.c index 14a3300848f6a0fb754b9d34bdacbc31b90f5d07..ebd2cbe3cbc11c2aede3819c414020b9344ec1f9 100644 --- a/src/misc.c +++ b/src/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. */ @@ -124,6 +125,17 @@ void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts, *tz = EXFAT_TZ_VALID; } +/* + * The timestamp for access_time has double seconds granularity. + * (There is no 10msIncrement field for access_time unlike create/modify_time) + * atime also 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/src/namei.c b/src/namei.c index a8681d91f56900107ea3df90e2b6dd986045a7bc..b72d782568b811ece222db0dd3575fd8bf2c958a 100644 --- a/src/namei.c +++ b/src/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/src/super.c b/src/super.c index ee42ecf59059a6c9bf61f5b6ec19efde21a4d897..0565d5539d57c6678c81997228dc3b8116eb864c 100644 --- a/src/super.c +++ b/src/super.c @@ -342,6 +342,7 @@ 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; } -- 2.31.1