[PATCH] nilfs2: use time64_t internally

From: Arnd Bergmann
Date: Mon Jan 22 2018 - 16:11:12 EST


The superblock and segment timestamps are used only internally in nilfs2
and can be read out using sysfs. Since we are using the old 'get_seconds()'
interface and store the data as timestamps, the behavior differs slightly
between 64-bit and 32-bit kernels, the latter will show incorrect timestamps
after 2038 in sysfs, and presumably fail completely in 2106 as comparisons
go wrong.

This changes nilfs2 to use time64_t with ktime_get_real_seconds() to handle
timestamps, making the behavior consistent and correct on both 32-bit
and 64-bit machines.

The on-disk format already uses 64-bit timestamps, so nothing changes
there.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
fs/nilfs2/segbuf.c | 2 +-
fs/nilfs2/segbuf.h | 4 ++--
fs/nilfs2/segment.c | 2 +-
fs/nilfs2/segment.h | 2 +-
fs/nilfs2/sufile.c | 2 +-
fs/nilfs2/sufile.h | 2 +-
fs/nilfs2/super.c | 4 ++--
fs/nilfs2/sysfs.c | 21 ++++++++++-----------
fs/nilfs2/the_nilfs.h | 8 ++++----
9 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c
index 6c5009cc4e6f..68cb9e4740b4 100644
--- a/fs/nilfs2/segbuf.c
+++ b/fs/nilfs2/segbuf.c
@@ -130,7 +130,7 @@ int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *segbuf,
}

int nilfs_segbuf_reset(struct nilfs_segment_buffer *segbuf, unsigned int flags,
- time_t ctime, __u64 cno)
+ time64_t ctime, __u64 cno)
{
int err;

diff --git a/fs/nilfs2/segbuf.h b/fs/nilfs2/segbuf.h
index 7bbccc099709..10e16935fff6 100644
--- a/fs/nilfs2/segbuf.h
+++ b/fs/nilfs2/segbuf.h
@@ -46,7 +46,7 @@ struct nilfs_segsum_info {
unsigned long nfileblk;
u64 seg_seq;
__u64 cno;
- time_t ctime;
+ time64_t ctime;
sector_t next;
};

@@ -120,7 +120,7 @@ void nilfs_segbuf_map_cont(struct nilfs_segment_buffer *segbuf,
struct nilfs_segment_buffer *prev);
void nilfs_segbuf_set_next_segnum(struct nilfs_segment_buffer *, __u64,
struct the_nilfs *);
-int nilfs_segbuf_reset(struct nilfs_segment_buffer *, unsigned int, time_t,
+int nilfs_segbuf_reset(struct nilfs_segment_buffer *, unsigned int, time64_t,
__u64);
int nilfs_segbuf_extend_segsum(struct nilfs_segment_buffer *);
int nilfs_segbuf_extend_payload(struct nilfs_segment_buffer *,
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 9f3ffba41533..0953635e7d48 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -2040,7 +2040,7 @@ static int nilfs_segctor_do_construct(struct nilfs_sc_info *sci, int mode)
goto out;

/* Update time stamp */
- sci->sc_seg_ctime = get_seconds();
+ sci->sc_seg_ctime = ktime_get_real_seconds();

err = nilfs_segctor_collect(sci, nilfs, mode);
if (unlikely(err))
diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h
index 84084a4d9b3e..04634e3e3d58 100644
--- a/fs/nilfs2/segment.h
+++ b/fs/nilfs2/segment.h
@@ -157,7 +157,7 @@ struct nilfs_sc_info {
unsigned long sc_blk_cnt;
unsigned long sc_datablk_cnt;
unsigned long sc_nblk_this_inc;
- time_t sc_seg_ctime;
+ time64_t sc_seg_ctime;
__u64 sc_cno;
unsigned long sc_flags;

diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index 1341a41e7b43..c7fa139d50e8 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -526,7 +526,7 @@ int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum)
* @modtime: modification time (option)
*/
int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
- unsigned long nblocks, time_t modtime)
+ unsigned long nblocks, time64_t modtime)
{
struct buffer_head *bh;
struct nilfs_segment_usage *su;
diff --git a/fs/nilfs2/sufile.h b/fs/nilfs2/sufile.h
index 158a9190c8ec..673a891350f4 100644
--- a/fs/nilfs2/sufile.h
+++ b/fs/nilfs2/sufile.h
@@ -35,7 +35,7 @@ int nilfs_sufile_set_alloc_range(struct inode *sufile, __u64 start, __u64 end);
int nilfs_sufile_alloc(struct inode *, __u64 *);
int nilfs_sufile_mark_dirty(struct inode *sufile, __u64 segnum);
int nilfs_sufile_set_segment_usage(struct inode *sufile, __u64 segnum,
- unsigned long nblocks, time_t modtime);
+ unsigned long nblocks, time64_t modtime);
int nilfs_sufile_get_stat(struct inode *, struct nilfs_sustat *);
ssize_t nilfs_sufile_get_suinfo(struct inode *, __u64, void *, unsigned int,
size_t);
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 3073b646e1ba..6ffeca84d7c3 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -283,10 +283,10 @@ int nilfs_commit_super(struct super_block *sb, int flag)
{
struct the_nilfs *nilfs = sb->s_fs_info;
struct nilfs_super_block **sbp = nilfs->ns_sbp;
- time_t t;
+ time64_t t;

/* nilfs->ns_sem must be locked by the caller. */
- t = get_seconds();
+ t = ktime_get_real_seconds();
nilfs->ns_sbwtime = t;
sbp[0]->s_wtime = cpu_to_le64(t);
sbp[0]->s_sum = 0;
diff --git a/fs/nilfs2/sysfs.c b/fs/nilfs2/sysfs.c
index 490303e3d517..4b25837e7724 100644
--- a/fs/nilfs2/sysfs.c
+++ b/fs/nilfs2/sysfs.c
@@ -31,7 +31,7 @@ static struct kset *nilfs_kset;
#define NILFS_SHOW_TIME(time_t_val, buf) ({ \
struct tm res; \
int count = 0; \
- time_to_tm(time_t_val, 0, &res); \
+ time64_to_tm(time_t_val, 0, &res); \
res.tm_year += 1900; \
res.tm_mon += 1; \
count = scnprintf(buf, PAGE_SIZE, \
@@ -579,7 +579,7 @@ nilfs_segctor_last_seg_write_time_show(struct nilfs_segctor_attr *attr,
struct the_nilfs *nilfs,
char *buf)
{
- time_t ctime;
+ time64_t ctime;

down_read(&nilfs->ns_segctor_sem);
ctime = nilfs->ns_ctime;
@@ -593,13 +593,13 @@ nilfs_segctor_last_seg_write_time_secs_show(struct nilfs_segctor_attr *attr,
struct the_nilfs *nilfs,
char *buf)
{
- time_t ctime;
+ time64_t ctime;

down_read(&nilfs->ns_segctor_sem);
ctime = nilfs->ns_ctime;
up_read(&nilfs->ns_segctor_sem);

- return snprintf(buf, PAGE_SIZE, "%llu\n", (unsigned long long)ctime);
+ return snprintf(buf, PAGE_SIZE, "%llu\n", ctime);
}

static ssize_t
@@ -607,7 +607,7 @@ nilfs_segctor_last_nongc_write_time_show(struct nilfs_segctor_attr *attr,
struct the_nilfs *nilfs,
char *buf)
{
- time_t nongc_ctime;
+ time64_t nongc_ctime;

down_read(&nilfs->ns_segctor_sem);
nongc_ctime = nilfs->ns_nongc_ctime;
@@ -621,14 +621,13 @@ nilfs_segctor_last_nongc_write_time_secs_show(struct nilfs_segctor_attr *attr,
struct the_nilfs *nilfs,
char *buf)
{
- time_t nongc_ctime;
+ time64_t nongc_ctime;

down_read(&nilfs->ns_segctor_sem);
nongc_ctime = nilfs->ns_nongc_ctime;
up_read(&nilfs->ns_segctor_sem);

- return snprintf(buf, PAGE_SIZE, "%llu\n",
- (unsigned long long)nongc_ctime);
+ return snprintf(buf, PAGE_SIZE, "%llu\n", nongc_ctime);
}

static ssize_t
@@ -728,7 +727,7 @@ nilfs_superblock_sb_write_time_show(struct nilfs_superblock_attr *attr,
struct the_nilfs *nilfs,
char *buf)
{
- time_t sbwtime;
+ time64_t sbwtime;

down_read(&nilfs->ns_sem);
sbwtime = nilfs->ns_sbwtime;
@@ -742,13 +741,13 @@ nilfs_superblock_sb_write_time_secs_show(struct nilfs_superblock_attr *attr,
struct the_nilfs *nilfs,
char *buf)
{
- time_t sbwtime;
+ time64_t sbwtime;

down_read(&nilfs->ns_sem);
sbwtime = nilfs->ns_sbwtime;
up_read(&nilfs->ns_sem);

- return snprintf(buf, PAGE_SIZE, "%llu\n", (unsigned long long)sbwtime);
+ return snprintf(buf, PAGE_SIZE, "%llu\n", sbwtime);
}

static ssize_t
diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index 883d732b0259..36da1779f976 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -116,7 +116,7 @@ struct the_nilfs {
*/
struct buffer_head *ns_sbh[2];
struct nilfs_super_block *ns_sbp[2];
- time_t ns_sbwtime;
+ time64_t ns_sbwtime;
unsigned int ns_sbwcount;
unsigned int ns_sbsize;
unsigned int ns_mount_state;
@@ -131,8 +131,8 @@ struct the_nilfs {
__u64 ns_nextnum;
unsigned long ns_pseg_offset;
__u64 ns_cno;
- time_t ns_ctime;
- time_t ns_nongc_ctime;
+ time64_t ns_ctime;
+ time64_t ns_nongc_ctime;
atomic_t ns_ndirtyblks;

/*
@@ -267,7 +267,7 @@ struct nilfs_root {

static inline int nilfs_sb_need_update(struct the_nilfs *nilfs)
{
- u64 t = get_seconds();
+ u64 t = ktime_get_real_seconds();

return t < nilfs->ns_sbwtime ||
t > nilfs->ns_sbwtime + nilfs->ns_sb_update_freq;
--
2.9.0