xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

fat: add functions to update and truncate timestamps appropriately

Browse Source 
Add the fat-specific inode_operation ->update_time() and
fat_truncate_time() function to truncate the inode timestamps from 1
nanosecond to the appropriate granularity.

Link: http://lkml.kernel.org/r/38af1ba3c3cf0d7381ce7b63077ef8af75901532.1538363961.git.sorenson@redhat.com
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Frank Sorenson
2018-10-30 15:06:53 -07:00
committed by Linus Torvalds
parent d9f4d94261
commit 6bb885ecd7
6 changed files with 87 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

75
fs/fat/misc.c
View File

@@ -7,6 +7,7 @@
*/
#include "fat.h"
#include <linux/iversion.h>
/*
* fat_fs_error reports a file system problem that might indicate fa data
@@ -265,6 +266,80 @@ void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec64 *ts,
}
EXPORT_SYMBOL_GPL(fat_time_unix2fat);
static inline struct timespec64 fat_timespec64_trunc_2secs(struct timespec64 ts)
{
return (struct timespec64){ ts.tv_sec & ~1ULL, 0 };
}
/*
* truncate the various times with appropriate granularity:
* root inode:
* all times always 0
* all other inodes:
* mtime - 2 seconds
* ctime
* msdos - 2 seconds
* vfat - 10 milliseconds
* atime - 24 hours (00:00:00 in local timezone)
*/
int fat_truncate_time(struct inode *inode, struct timespec64 *now, int flags)
{
struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
struct timespec64 ts;
if (inode->i_ino == MSDOS_ROOT_INO)
return 0;
if (now == NULL) {
now = &ts;
ts = current_time(inode);
}
if (flags & S_ATIME) {
/* to localtime */
time64_t seconds = now->tv_sec - fat_tz_offset(sbi);
s32 remainder;
div_s64_rem(seconds, SECS_PER_DAY, &remainder);
/* to day boundary, and back to unix time */
seconds = seconds + fat_tz_offset(sbi) - remainder;
inode->i_atime = (struct timespec64){ seconds, 0 };
}
if (flags & S_CTIME) {
if (sbi->options.isvfat)
inode->i_ctime = timespec64_trunc(*now, 10000000);
else
inode->i_ctime = fat_timespec64_trunc_2secs(*now);
}
if (flags & S_MTIME)
inode->i_mtime = fat_timespec64_trunc_2secs(*now);
return 0;
}
EXPORT_SYMBOL_GPL(fat_truncate_time);
int fat_update_time(struct inode *inode, struct timespec64 *now, int flags)
{
int iflags = I_DIRTY_TIME;
bool dirty = false;
if (inode->i_ino == MSDOS_ROOT_INO)
return 0;
fat_truncate_time(inode, now, flags);
if (flags & S_VERSION)
dirty = inode_maybe_inc_iversion(inode, false);
if ((flags & (S_ATIME | S_CTIME | S_MTIME)) &&
!(inode->i_sb->s_flags & SB_LAZYTIME))
dirty = true;
if (dirty)
iflags |= I_DIRTY_SYNC;
__mark_inode_dirty(inode, iflags);
return 0;
}
EXPORT_SYMBOL_GPL(fat_update_time);
int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs)
{
int i, err = 0;