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 <sandeen@sandeen.net>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h
index 67d4e46..d67fb8a 100644
--- a/fs/exfat/exfat_fs.h
+++ b/fs/exfat/exfat_fs.h
@@ -507,6 +507,7 @@
__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 483f683..4f76764 100644
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -273,6 +273,7 @@
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 @@
}
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 14a3300..ebd2cbe 100644
--- a/fs/exfat/misc.c
+++ b/fs/exfat/misc.c
@@ -88,7 +88,8 @@
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 @@
*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/fs/exfat/namei.c b/fs/exfat/namei.c
index a8681d9..b72d782 100644
--- a/fs/exfat/namei.c
+++ b/fs/exfat/namei.c
@@ -595,6 +595,7 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 ee42ecf..0565d55 100644
--- a/fs/exfat/super.c
+++ b/fs/exfat/super.c
@@ -342,6 +342,7 @@
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;
}
