Delete timespec64_trunc()

PATCH Applied Deepa Dinamani 4 participants 14 messages Nov 30, 2019 – Dec 2, 2019

Subsystems (7)

VFS Memory technology devices (MTD) SMB client (CIFS) Kernel SMB3 server (ksmbd) +3 more subsystems

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Deepa Dinamani

author

2019-11-30 05:30 UTC #0 lore raw

cover Delete timespec64_trunc()

This series aims at deleting timespec64_trunc(). There is a new api: timestamp_truncate() that is the replacement api. The api additionally does a limits check on the filesystem timestamps.

The suggestion to open code some of the truncate logic came from Al Viro. And, this does make the code in some filesystems easy to follow.

The series also does some update_time() cleanup as suggested by Al Viro.

Deepa Dinamani (7):
fs: fat: Eliminate timespec64_trunc() usage
fs: cifs: Fix atime update check vs mtime
fs: cifs: Delete usage of timespec64_trunc
fs: ceph: Delete timespec64_trunc() usage
fs: ubifs: Eliminate timespec64_trunc() usage
fs: Delete timespec64_trunc()
fs: Do not overload update_time

 fs/ceph/mds_client.c |  3 +--
 fs/cifs/inode.c      | 15 ++++++++-------
 fs/fat/misc.c        | 10 +++++++++-
 fs/inode.c           | 30 +++---------------------------
 fs/ubifs/sb.c        | 11 ++++-------
 include/linux/fs.h   |  1 -
 6 files changed, 25 insertions(+), 45 deletions(-)

Signature · 9 lines

2.17.1

Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

Deepa Dinamani

author

2019-11-30 05:30 UTC #7 lore raw

PATCH 4/7 fs: ceph: Delete timespec64_trunc() usage

Since ceph always uses ns granularity, skip the
truncation which is a no-op.

Signed-off-by Deepa Dinamani <[email protected]>

Cc [email protected]

---
 fs/ceph/mds_client.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

fs/ceph/mds_client.c +1 -2

index 068b029cf073..c2aa290f6c3e 100644
@@ -2088,8 +2088,7 @@ ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
 	init_completion(&req->r_safe_completion);
 	INIT_LIST_HEAD(&req->r_unsafe_item);
 
-	ktime_get_coarse_real_ts64(&ts);
-	req->r_stamp = timespec64_trunc(ts, mdsc->fsc->sb->s_time_gran);
+	ktime_get_coarse_real_ts64(&req->r_stamp);
 
 	req->r_op = op;
 	req->r_direct_mode = mode;

Signature · 1 line

2.17.1

Deepa Dinamani

author

2019-11-30 05:31 UTC #1 lore raw

PATCH 1/7 fs: fat: Eliminate timespec64_trunc() usage

In reply to Deepa Dinamani

timespec64_trunc() is being deleted.

timestamp_truncate() is the replacement api for timespec64_trunc. timestamp_truncate() additionally clamps timestamps to make sure the timestamps lie within the permitted range for the filesystem.

But, fat always truncates the times locally after it obtains the timestamps from current_time().
Implement a local version here along the lines of existing truncate functions.

Suggested-by Al Viro <[email protected]>

Signed-off-by Deepa Dinamani <[email protected]>

Cc [email protected]

---
 fs/fat/misc.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

fs/fat/misc.c +9 -1

index 1e08bd54c5fb..f1b2a1fc2a6a 100644
@@ -271,6 +271,14 @@ static inline struct timespec64 fat_timespec64_trunc_2secs(struct timespec64 ts)
 {
 	return (struct timespec64){ ts.tv_sec & ~1ULL, 0 };
 }
+
+static inline struct timespec64 fat_timespec64_trunc_10ms(struct timespec64 ts)
+{
+	if (ts.tv_nsec)
+		ts.tv_nsec -= ts.tv_nsec % 10000000UL;
+	return ts;
+}
+
 /*
  * truncate the various times with appropriate granularity:
  *   root inode:

@@ -308,7 +316,7 @@ int fat_truncate_time(struct inode *inode, struct timespec64 *now, int flags)
 	}
 	if (flags & S_CTIME) {
 		if (sbi->options.isvfat)
-			inode->i_ctime = timespec64_trunc(*now, 10000000);
+			inode->i_ctime = fat_timespec64_trunc_10ms(*now);
 		else
 			inode->i_ctime = fat_timespec64_trunc_2secs(*now);
 	}

Signature · 1 line

2.17.1

Deepa Dinamani

author

2019-11-30 05:31 UTC #2 lore raw

PATCH 2/7 fs: cifs: Fix atime update check vs mtime

In reply to Deepa Dinamani

According to the comment in the code and commit log, some apps expect atime >= mtime; but the introduced code results in atime==mtime. Fix the comparison to guard against atime<mtime.

Fixes 9b9c5bea0b96 ("cifs: do not return atime less than mtime")

Signed-off-by Deepa Dinamani <[email protected]>

Cc [email protected]

---
 fs/cifs/inode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

fs/cifs/inode.c +1 -1

index 8a76195e8a69..ca76a9287456 100644
@@ -163,7 +163,7 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
 
 	spin_lock(&inode->i_lock);
 	/* we do not want atime to be less than mtime, it broke some apps */
-	if (timespec64_compare(&fattr->cf_atime, &fattr->cf_mtime))
+	if (timespec64_compare(&fattr->cf_atime, &fattr->cf_mtime) < 0)
 		inode->i_atime = fattr->cf_mtime;
 	else
 		inode->i_atime = fattr->cf_atime;

Signature · 1 line

2.17.1

Deepa Dinamani

author

2019-11-30 05:31 UTC #4 lore raw

PATCH 3/7 fs: cifs: Delete usage of timespec64_trunc

In reply to Deepa Dinamani

Truncate the timestamps in the struct cifs_attr at the site of assignment to inode times. This
helps us use the right fs api timestamp_trucate() to perform the truncation.

Also update the ktime_get_* api to match the one used in current_time(). This allows for timestamps to be updated the same way always.

Signed-off-by Deepa Dinamani <[email protected]>

Cc [email protected]

---
 fs/cifs/inode.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

fs/cifs/inode.c +7 -6

index ca76a9287456..026ed49e8aa4 100644
@@ -113,6 +113,7 @@ cifs_revalidate_cache(struct inode *inode, struct cifs_fattr *fattr)
 	}
 
 	 /* revalidate if mtime or size have changed */
+	fattr->cf_mtime = timestamp_truncate(fattr->cf_mtime, inode);
 	if (timespec64_equal(&inode->i_mtime, &fattr->cf_mtime) &&
 	    cifs_i->server_eof == fattr->cf_eof) {
 		cifs_dbg(FYI, "%s: inode %llu is unchanged\n",

@@ -162,6 +163,9 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
 	cifs_revalidate_cache(inode, fattr);
 
 	spin_lock(&inode->i_lock);
+	fattr->cf_mtime = timestamp_truncate(fattr->cf_mtime, inode);
+	fattr->cf_atime = timestamp_truncate(fattr->cf_atime, inode);
+	fattr->cf_ctime = timestamp_truncate(fattr->cf_ctime, inode);
 	/* we do not want atime to be less than mtime, it broke some apps */
 	if (timespec64_compare(&fattr->cf_atime, &fattr->cf_mtime) < 0)
 		inode->i_atime = fattr->cf_mtime;

@@ -329,8 +333,7 @@ cifs_create_dfs_fattr(struct cifs_fattr *fattr, struct super_block *sb)
 	fattr->cf_mode = S_IFDIR | S_IXUGO | S_IRWXU;
 	fattr->cf_uid = cifs_sb->mnt_uid;
 	fattr->cf_gid = cifs_sb->mnt_gid;
-	ktime_get_real_ts64(&fattr->cf_mtime);
-	fattr->cf_mtime = timespec64_trunc(fattr->cf_mtime, sb->s_time_gran);
+	ktime_get_coarse_real_ts64(&fattr->cf_mtime);
 	fattr->cf_atime = fattr->cf_ctime = fattr->cf_mtime;
 	fattr->cf_nlink = 2;
 	fattr->cf_flags = CIFS_FATTR_DFS_REFERRAL;

@@ -609,10 +612,8 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
 
 	if (info->LastAccessTime)
 		fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
-	else {
-		ktime_get_real_ts64(&fattr->cf_atime);
-		fattr->cf_atime = timespec64_trunc(fattr->cf_atime, sb->s_time_gran);
-	}
+	else
+		ktime_get_coarse_real_ts64(&fattr->cf_atime);
 
 	fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
 	fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);

Signature · 1 line

2.17.1

Deepa Dinamani

author

2019-11-30 05:31 UTC #8 lore raw

PATCH 5/7 fs: ubifs: Eliminate timespec64_trunc() usage

In reply to Deepa Dinamani

DEFAULT_TIME_GRAN is seconds granularity. We can just drop the nsec while creating the default root node. Delete the unneeded call to timespec64_trunc().

Also update the ktime_get_* api to match the one used in current_time(). This allows for the timestamps to be updated by using the same ktime_get_* api always.

Signed-off-by Deepa Dinamani <[email protected]>

Cc [email protected]

---
 fs/ubifs/sb.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

fs/ubifs/sb.c +4 -7

index 2b7c04bf8983..93d550be4c11 100644
@@ -84,7 +84,6 @@ static int create_default_filesystem(struct ubifs_info *c)
 	int idx_node_size;
 	long long tmp64, main_bytes;
 	__le64 tmp_le64;
-	__le32 tmp_le32;
 	struct timespec64 ts;
 	u8 hash[UBIFS_HASH_ARR_SZ];
 	u8 hash_lpt[UBIFS_HASH_ARR_SZ];

@@ -291,16 +290,14 @@ static int create_default_filesystem(struct ubifs_info *c)
 	ino->creat_sqnum = cpu_to_le64(++c->max_sqnum);
 	ino->nlink = cpu_to_le32(2);
 
-	ktime_get_real_ts64(&ts);
-	ts = timespec64_trunc(ts, DEFAULT_TIME_GRAN);
+	ktime_get_coarse_real_ts64(&ts);
 	tmp_le64 = cpu_to_le64(ts.tv_sec);
 	ino->atime_sec   = tmp_le64;
 	ino->ctime_sec   = tmp_le64;
 	ino->mtime_sec   = tmp_le64;
-	tmp_le32 = cpu_to_le32(ts.tv_nsec);
-	ino->atime_nsec  = tmp_le32;
-	ino->ctime_nsec  = tmp_le32;
-	ino->mtime_nsec  = tmp_le32;
+	ino->atime_nsec  = 0;
+	ino->ctime_nsec  = 0;
+	ino->mtime_nsec  = 0;
 	ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
 	ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ);

Signature · 1 line

2.17.1

Deepa Dinamani

author

2019-11-30 05:31 UTC #9 lore raw

PATCH 6/7 fs: Delete timespec64_trunc()

In reply to Deepa Dinamani

There are no more callers to the function remaining.

Signed-off-by Deepa Dinamani <[email protected]>

---
 fs/inode.c         | 24 ------------------------
 include/linux/fs.h |  1 -
 2 files changed, 25 deletions(-)

fs/inode.c +0 ~~-24~~

index fef457a42882..12c9e38529c9 100644
@@ -2145,30 +2145,6 @@ void inode_nohighmem(struct inode *inode)
 }
 EXPORT_SYMBOL(inode_nohighmem);
 
-/**
- * timespec64_trunc - Truncate timespec64 to a granularity
- * @t: Timespec64
- * @gran: Granularity in ns.
- *
- * Truncate a timespec64 to a granularity. Always rounds down. gran must
- * not be 0 nor greater than a second (NSEC_PER_SEC, or 10^9 ns).
- */
-struct timespec64 timespec64_trunc(struct timespec64 t, unsigned gran)
-{
-	/* Avoid division in the common cases 1 ns and 1 s. */
-	if (gran == 1) {
-		/* nothing */
-	} else if (gran == NSEC_PER_SEC) {
-		t.tv_nsec = 0;
-	} else if (gran > 1 && gran < NSEC_PER_SEC) {
-		t.tv_nsec -= t.tv_nsec % gran;
-	} else {
-		WARN(1, "illegal file time granularity: %u", gran);
-	}
-	return t;
-}
-EXPORT_SYMBOL(timespec64_trunc);
-
 /**
  * timestamp_truncate - Truncate timespec to a granularity
  * @t: Timespec

include/linux/fs.h +0 -1

index 98e0349adb52..46dd7e6f6d73 100644
@@ -1575,7 +1575,6 @@ static inline void i_gid_write(struct inode *inode, gid_t gid)
 	inode->i_gid = make_kgid(inode->i_sb->s_user_ns, gid);
 }
 
-extern struct timespec64 timespec64_trunc(struct timespec64 t, unsigned gran);
 extern struct timespec64 current_time(struct inode *inode);
 
 /*

Signature · 1 line

2.17.1

Deepa Dinamani

author

2019-11-30 05:31 UTC #10 lore raw

PATCH 7/7 fs: Do not overload update_time

In reply to Deepa Dinamani

update_time() also has an internal function pointer update_time. Even though this works correctly, it is confusing to the readers.

Use a different name for the local variable.

Suggested-by Al Viro <[email protected]>

Signed-off-by Deepa Dinamani <[email protected]>

---
 fs/inode.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

fs/inode.c +3 -3

index 12c9e38529c9..0be58a680457 100644
@@ -1675,12 +1675,12 @@ EXPORT_SYMBOL(generic_update_time);
  */
 static int update_time(struct inode *inode, struct timespec64 *time, int flags)
 {
-	int (*update_time)(struct inode *, struct timespec64 *, int);
+	int (*cb)(struct inode *, struct timespec64 *, int);
 
-	update_time = inode->i_op->update_time ? inode->i_op->update_time :
+	cb = inode->i_op->update_time ? inode->i_op->update_time :
 		generic_update_time;
 
-	return update_time(inode, time, flags);
+	return cb(inode, time, flags);
 }
 
 /**

Signature · 1 line

2.17.1

Steve French

2019-11-30 21:25 UTC #5 lore raw

Re: [PATCH 3/7] fs: cifs: Delete usage of timespec64_trunc

In reply to Deepa Dinamani

Is this intended to merge separately or do you want it merged through the cifs git tree?

Quoted 70 lines · Deepa Dinamani

Truncate the timestamps in the struct cifs_attr at the site of assignment to inode times. This
helps us use the right fs api timestamp_trucate() to perform the truncation.

Also update the ktime_get_* api to match the one used in current_time(). This allows for timestamps to be updated the same way always.

Signed-off-by Deepa Dinamani <[email protected]>

Cc [email protected]

---
 fs/cifs/inode.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

fs/cifs/inode.c +7 -7

index ca76a9287456..026ed49e8aa4 100644
@@ -113,6 +113,7 @@ cifs_revalidate_cache(struct inode *inode, struct cifs_fattr *fattr)
        }
 
         /* revalidate if mtime or size have changed */
+       fattr->cf_mtime = timestamp_truncate(fattr->cf_mtime, inode);
        if (timespec64_equal(&inode->i_mtime, &fattr->cf_mtime) &&
            cifs_i->server_eof == fattr->cf_eof) {
                cifs_dbg(FYI, "%s: inode %llu is unchanged\n",

@@ -162,6 +163,9 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
        cifs_revalidate_cache(inode, fattr);
 
        spin_lock(&inode->i_lock);
+       fattr->cf_mtime = timestamp_truncate(fattr->cf_mtime, inode);
+       fattr->cf_atime = timestamp_truncate(fattr->cf_atime, inode);
+       fattr->cf_ctime = timestamp_truncate(fattr->cf_ctime, inode);
        /* we do not want atime to be less than mtime, it broke some apps */
        if (timespec64_compare(&fattr->cf_atime, &fattr->cf_mtime) < 0)
                inode->i_atime = fattr->cf_mtime;

@@ -329,8 +333,7 @@ cifs_create_dfs_fattr(struct cifs_fattr *fattr, struct super_block *sb)
        fattr->cf_mode = S_IFDIR | S_IXUGO | S_IRWXU;
        fattr->cf_uid = cifs_sb->mnt_uid;
        fattr->cf_gid = cifs_sb->mnt_gid;
-       ktime_get_real_ts64(&fattr->cf_mtime);
-       fattr->cf_mtime = timespec64_trunc(fattr->cf_mtime, sb->s_time_gran);
+       ktime_get_coarse_real_ts64(&fattr->cf_mtime);
        fattr->cf_atime = fattr->cf_ctime = fattr->cf_mtime;
        fattr->cf_nlink = 2;
        fattr->cf_flags = CIFS_FATTR_DFS_REFERRAL;

@@ -609,10 +612,8 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
 
        if (info->LastAccessTime)
                fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
-       else {
-               ktime_get_real_ts64(&fattr->cf_atime);
-               fattr->cf_atime = timespec64_trunc(fattr->cf_atime, sb->s_time_gran);
-       }
+       else
+               ktime_get_coarse_real_ts64(&fattr->cf_atime);
 
        fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
        fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
--

2.17.1

Signature · 3 lines

Thanks,

Steve

Deepa Dinamani

author

2019-12-01 05:35 UTC #6 lore raw

Re: [PATCH 3/7] fs: cifs: Delete usage of timespec64_trunc

Quoted 3 lines · Steve French

Is this intended to merge separately or do you want it merged through the cifs git tree?

It would be simplest for all uses of timespec64_trunc to be removed through the same tree. Otherwise, whoever takes the [PATCH 6/7] ("fs:
Delete timespec64_trunc()") would have to depend on your tree.

Thanks,
-Deepa

Steve French

Applied

2019-12-01 18:23 UTC #3 lore raw

Re: [PATCH 2/7] fs: cifs: Fix atime update check vs mtime

In reply to Deepa Dinamani

merged into cifs-2.6.git for-next

Quoted 29 lines · Deepa Dinamani

According to the comment in the code and commit log, some apps expect atime >= mtime; but the introduced code results in atime==mtime. Fix the comparison to guard against atime<mtime.
Fixes 9b9c5bea0b96 ("cifs: do not return atime less than mtime")
Signed-off-by Deepa Dinamani <[email protected]>
Cc [email protected]
Cc [email protected]
---
 fs/cifs/inode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
fs/cifs/inode.c +1 -2
index 8a76195e8a69..ca76a9287456 100644
@@ -163,7 +163,7 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
 
        spin_lock(&inode->i_lock);
        /* we do not want atime to be less than mtime, it broke some apps */
-       if (timespec64_compare(&fattr->cf_atime, &fattr->cf_mtime))
+       if (timespec64_compare(&fattr->cf_atime, &fattr->cf_mtime) < 0)
                inode->i_atime = fattr->cf_mtime;
        else
                inode->i_atime = fattr->cf_atime;
--
2.17.1

Signature · 3 lines

Thanks,

Steve

Dave Chinner

2019-12-01 20:52 UTC #11 lore raw

Re: [PATCH 7/7] fs: Do not overload update_time

In reply to Deepa Dinamani

Quoted 19 lines · Deepa Dinamani

update_time() also has an internal function pointer update_time. Even though this works correctly, it is confusing to the readers.
Use a different name for the local variable.
Suggested-by Al Viro <[email protected]>
Signed-off-by Deepa Dinamani <[email protected]>
---
 fs/inode.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
fs/inode.c +0 -0
index 12c9e38529c9..0be58a680457 100644
@@ -1675,12 +1675,12 @@ EXPORT_SYMBOL(generic_update_time);
  */
 static int update_time(struct inode *inode, struct timespec64 *time, int flags)

fs/inode.c EXPORT_SYMBOL(generic_update_time); · line 1683

Quoted 10 lines

fs/inode.c +3 -3

 {
-	int (*update_time)(struct inode *, struct timespec64 *, int);
+	int (*cb)(struct inode *, struct timespec64 *, int);
 
-	update_time = inode->i_op->update_time ? inode->i_op->update_time :
+	cb = inode->i_op->update_time ? inode->i_op->update_time :
 		generic_update_time;
 
-	return update_time(inode, time, flags);
+	return cb(inode, time, flags);

What's wrong with a simple if() like we use everywhere else for this sort of thing?

	if (inode->i_op->update_time)
		return inode->i_op->update_time(inode, time, flags);
	return generic_update_time(inode, time, flags);

-Dave.

Signature · 2 lines

Dave Chinner
[email protected]

Christoph Hellwig

2019-12-02 17:48 UTC #12 lore raw

Re: [PATCH 7/7] fs: Do not overload update_time

In reply to Deepa Dinamani

fs/inode.c EXPORT_SYMBOL(generic_update_time); · line 1683

Quoted 9 lines · Deepa Dinamani

fs/inode.c +3 -3

-	int (*update_time)(struct inode *, struct timespec64 *, int);
+	int (*cb)(struct inode *, struct timespec64 *, int);
 
-	update_time = inode->i_op->update_time ? inode->i_op->update_time :
+	cb = inode->i_op->update_time ? inode->i_op->update_time :
 		generic_update_time;
 
-	return update_time(inode, time, flags);
+	return cb(inode, time, flags);

Just killing the pointless local variable cleans the function op, and also avoids the expensive indirect call for the common case:

	if (inode->i_op->update_time)
		return inode->i_op->update_time(inode, time, flags);
	return generic_update_time(inode, time, flags);

Deepa Dinamani

author

2019-12-02 23:13 UTC #13 lore raw

Re: [PATCH 7/7] fs: Do not overload update_time

Quoted 9 lines · Christoph Hellwig

Quoted 7 lines · Deepa Dinamani

fs/inode.c +2 -2

-     int (*update_time)(struct inode *, struct timespec64 *, int);
+     int (*cb)(struct inode *, struct timespec64 *, int);
 
-     update_time = inode->i_op->update_time ? inode->i_op->update_time :
+     cb = inode->i_op->update_time ? inode->i_op->update_time :
              generic_update_time;

Quoted 5 lines

fs/inode.c EXPORT_SYMBOL(generic_update_time); · line 1683
Quoted 2 lines
fs/inode.c +1 -1
-     return update_time(inode, time, flags);
+     return cb(inode, time, flags);
Just killing the pointless local variable cleans the function op, and also avoids the expensive indirect call for the common case:

Will update this in v2. Thanks.

-Deepa