Commit 81df1ad4 authored by Eric Sandeen's avatar Eric Sandeen Committed by Namjae Jeon
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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: default avatarEric Sandeen <sandeen@sandeen.net>
Signed-off-by: default avatarNamjae Jeon <namjae.jeon@samsung.com>
parent 674a9985

fs/exfat/exfat_fs.h

+1 −0
Original line number Diff line number Diff line
@@ -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,

fs/exfat/file.c

+2 −0
Original line number Diff line number Diff line
@@ -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:

fs/exfat/misc.c

+13 −1
Original line number Diff line number Diff line
@@ -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)

{

fs/exfat/namei.c

+7 −0
Original line number Diff line number Diff line
@@ -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

fs/exfat/super.c

+1 −0
Original line number Diff line number Diff line
@@ -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;

}