2023-07-05 19:07:46

by Jeff Layton

[permalink] [raw]
Subject: [PATCH v2 42/92] ext4: convert to ctime accessor functions

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <[email protected]>
---
fs/ext4/acl.c | 2 +-
fs/ext4/ext4.h | 21 +++++++++++++++++++++
fs/ext4/extents.c | 12 ++++++------
fs/ext4/ialloc.c | 2 +-
fs/ext4/inline.c | 4 ++--
fs/ext4/inode.c | 16 +++++++---------
fs/ext4/ioctl.c | 9 +++++----
fs/ext4/namei.c | 26 ++++++++++++--------------
fs/ext4/super.c | 2 +-
fs/ext4/xattr.c | 6 +++---
10 files changed, 59 insertions(+), 41 deletions(-)

diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
index 27fcbddfb148..3bffe862f954 100644
--- a/fs/ext4/acl.c
+++ b/fs/ext4/acl.c
@@ -259,7 +259,7 @@ ext4_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
error = __ext4_set_acl(handle, inode, type, acl, 0 /* xattr_flags */);
if (!error && update_mode) {
inode->i_mode = mode;
- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
error = ext4_mark_inode_dirty(handle, inode);
}
out_stop:
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 0a2d55faa095..d502b930431b 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3823,6 +3823,27 @@ static inline int ext4_buffer_uptodate(struct buffer_head *bh)
return buffer_uptodate(bh);
}

+static inline void ext4_inode_set_ctime(struct inode *inode, struct ext4_inode *raw_inode)
+{
+ struct timespec64 ctime = inode_get_ctime(inode);
+
+ if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), i_ctime_extra)) {
+ raw_inode->i_ctime = cpu_to_le32(ctime.tv_sec);
+ raw_inode->i_ctime_extra = ext4_encode_extra_time(&ctime);
+ } else {
+ raw_inode->i_ctime = cpu_to_le32(clamp_t(int32_t, ctime.tv_sec, S32_MIN, S32_MAX));
+ }
+}
+
+static inline void ext4_inode_get_ctime(struct inode *inode, const struct ext4_inode *raw_inode)
+{
+ struct timespec64 ctime = { .tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime) };
+
+ if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), i_ctime_extra))
+ ext4_decode_extra_time(&ctime, raw_inode->i_ctime_extra);
+ inode_set_ctime(inode, ctime.tv_sec, ctime.tv_nsec);
+}
+
#endif /* __KERNEL__ */

#define EFSBADCRC EBADMSG /* Bad CRC detected */
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index e4115d338f10..202c76996b62 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4476,12 +4476,12 @@ static int ext4_alloc_file_blocks(struct file *file, ext4_lblk_t offset,
map.m_lblk += ret;
map.m_len = len = len - ret;
epos = (loff_t)map.m_lblk << inode->i_blkbits;
- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
if (new_size) {
if (epos > new_size)
epos = new_size;
if (ext4_update_inode_size(inode, epos) & 0x1)
- inode->i_mtime = inode->i_ctime;
+ inode->i_mtime = inode_get_ctime(inode);
}
ret2 = ext4_mark_inode_dirty(handle, inode);
ext4_update_inode_fsync_trans(handle, inode, 1);
@@ -4617,7 +4617,7 @@ static long ext4_zero_range(struct file *file, loff_t offset,

/* Now release the pages and zero block aligned part of pages */
truncate_pagecache_range(inode, start, end - 1);
- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);

ret = ext4_alloc_file_blocks(file, lblk, max_blocks, new_size,
flags);
@@ -4642,7 +4642,7 @@ static long ext4_zero_range(struct file *file, loff_t offset,
goto out_mutex;
}

- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);
if (new_size)
ext4_update_inode_size(inode, new_size);
ret = ext4_mark_inode_dirty(handle, inode);
@@ -5378,7 +5378,7 @@ static int ext4_collapse_range(struct file *file, loff_t offset, loff_t len)
up_write(&EXT4_I(inode)->i_data_sem);
if (IS_SYNC(inode))
ext4_handle_sync(handle);
- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);
ret = ext4_mark_inode_dirty(handle, inode);
ext4_update_inode_fsync_trans(handle, inode, 1);

@@ -5488,7 +5488,7 @@ static int ext4_insert_range(struct file *file, loff_t offset, loff_t len)
/* Expand file to avoid data loss if there is error while shifting */
inode->i_size += len;
EXT4_I(inode)->i_disksize += len;
- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);
ret = ext4_mark_inode_dirty(handle, inode);
if (ret)
goto out_stop;
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 754f961cd9fd..48abef5f23e7 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -1250,7 +1250,7 @@ struct inode *__ext4_new_inode(struct mnt_idmap *idmap,
inode->i_ino = ino + group * EXT4_INODES_PER_GROUP(sb);
/* This is the optimal IO size (for stat), not the fs block size */
inode->i_blocks = 0;
- inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode->i_atime = inode_set_ctime_current(inode);
ei->i_crtime = inode->i_mtime;

memset(ei->i_data, 0, sizeof(ei->i_data));
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index a4b7e4bc32d4..003861037374 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -1037,7 +1037,7 @@ static int ext4_add_dirent_to_inline(handle_t *handle,
* happen is that the times are slightly out of date
* and/or different from the directory change time.
*/
- dir->i_mtime = dir->i_ctime = current_time(dir);
+ dir->i_mtime = inode_set_ctime_current(dir);
ext4_update_dx_flag(dir);
inode_inc_iversion(dir);
return 1;
@@ -1991,7 +1991,7 @@ int ext4_inline_data_truncate(struct inode *inode, int *has_inline)
ext4_orphan_del(handle, inode);

if (err == 0) {
- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);
err = ext4_mark_inode_dirty(handle, inode);
if (IS_SYNC(inode))
ext4_handle_sync(handle);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 3d253e250871..bbc57954dfd3 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3986,7 +3986,7 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length)
if (IS_SYNC(inode))
ext4_handle_sync(handle);

- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);
ret2 = ext4_mark_inode_dirty(handle, inode);
if (unlikely(ret2))
ret = ret2;
@@ -4146,7 +4146,7 @@ int ext4_truncate(struct inode *inode)
if (inode->i_nlink)
ext4_orphan_del(handle, inode);

- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);
err2 = ext4_mark_inode_dirty(handle, inode);
if (unlikely(err2 && !err))
err = err2;
@@ -4249,7 +4249,7 @@ static int ext4_fill_raw_inode(struct inode *inode, struct ext4_inode *raw_inode
}
raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);

- EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode);
+ ext4_inode_set_ctime(inode, raw_inode);
EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode);
EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode);
@@ -4858,7 +4858,7 @@ struct inode *__ext4_iget(struct super_block *sb, unsigned long ino,
}
}

- EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode);
+ ext4_inode_get_ctime(inode, raw_inode);
EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode);
EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode);
EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode);
@@ -4981,7 +4981,7 @@ static void __ext4_update_other_inode_time(struct super_block *sb,
spin_unlock(&inode->i_lock);

spin_lock(&ei->i_raw_lock);
- EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode);
+ ext4_inode_get_ctime(inode, raw_inode);
EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode);
EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
ext4_inode_csum_set(inode, raw_inode, ei);
@@ -5376,10 +5376,8 @@ int ext4_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
* Update c/mtime on truncate up, ext4_truncate() will
* update c/mtime in shrink case below
*/
- if (!shrink) {
- inode->i_mtime = current_time(inode);
- inode->i_ctime = inode->i_mtime;
- }
+ if (!shrink)
+ inode->i_mtime = inode_set_ctime_current(inode);

if (shrink)
ext4_fc_track_range(handle, inode,
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 331859511f80..b0349f451863 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -449,7 +449,8 @@ static long swap_inode_boot_loader(struct super_block *sb,
diff = size - size_bl;
swap_inode_data(inode, inode_bl);

- inode->i_ctime = inode_bl->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
+ inode_set_ctime_current(inode_bl);
inode_inc_iversion(inode);

inode->i_generation = get_random_u32();
@@ -663,7 +664,7 @@ static int ext4_ioctl_setflags(struct inode *inode,

ext4_set_inode_flags(inode, false);

- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
inode_inc_iversion(inode);

err = ext4_mark_iloc_dirty(handle, inode, &iloc);
@@ -774,7 +775,7 @@ static int ext4_ioctl_setproject(struct inode *inode, __u32 projid)
}

EXT4_I(inode)->i_projid = kprojid;
- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
inode_inc_iversion(inode);
out_dirty:
rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
@@ -1266,7 +1267,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
}
err = ext4_reserve_inode_write(handle, inode, &iloc);
if (err == 0) {
- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
inode_inc_iversion(inode);
inode->i_generation = generation;
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 0caf6c730ce3..07f6d96ebc60 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2203,7 +2203,7 @@ static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
* happen is that the times are slightly out of date
* and/or different from the directory change time.
*/
- dir->i_mtime = dir->i_ctime = current_time(dir);
+ dir->i_mtime = inode_set_ctime_current(dir);
ext4_update_dx_flag(dir);
inode_inc_iversion(dir);
err2 = ext4_mark_inode_dirty(handle, dir);
@@ -3197,7 +3197,8 @@ static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
* recovery. */
inode->i_size = 0;
ext4_orphan_add(handle, inode);
- inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode);
+ dir->i_mtime = inode_set_ctime_current(dir);
+ inode_set_ctime_current(inode);
retval = ext4_mark_inode_dirty(handle, inode);
if (retval)
goto end_rmdir;
@@ -3271,7 +3272,7 @@ int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
retval = ext4_delete_entry(handle, dir, de, bh);
if (retval)
goto out_handle;
- dir->i_ctime = dir->i_mtime = current_time(dir);
+ dir->i_mtime = inode_set_ctime_current(dir);
ext4_update_dx_flag(dir);
retval = ext4_mark_inode_dirty(handle, dir);
if (retval)
@@ -3286,7 +3287,7 @@ int __ext4_unlink(struct inode *dir, const struct qstr *d_name,
drop_nlink(inode);
if (!inode->i_nlink)
ext4_orphan_add(handle, inode);
- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
retval = ext4_mark_inode_dirty(handle, inode);
if (dentry && !retval)
ext4_fc_track_unlink(handle, dentry);
@@ -3463,7 +3464,7 @@ int __ext4_link(struct inode *dir, struct inode *inode, struct dentry *dentry)
if (IS_DIRSYNC(dir))
ext4_handle_sync(handle);

- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
ext4_inc_count(inode);
ihold(inode);

@@ -3641,8 +3642,7 @@ static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
if (ext4_has_feature_filetype(ent->dir->i_sb))
ent->de->file_type = file_type;
inode_inc_iversion(ent->dir);
- ent->dir->i_ctime = ent->dir->i_mtime =
- current_time(ent->dir);
+ ent->dir->i_mtime = inode_set_ctime_current(ent->dir);
retval = ext4_mark_inode_dirty(handle, ent->dir);
BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
if (!ent->inlined) {
@@ -3941,7 +3941,7 @@ static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir,
* Like most other Unix systems, set the ctime for inodes on a
* rename.
*/
- old.inode->i_ctime = current_time(old.inode);
+ inode_set_ctime_current(old.inode);
retval = ext4_mark_inode_dirty(handle, old.inode);
if (unlikely(retval))
goto end_rename;
@@ -3955,9 +3955,9 @@ static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir,

if (new.inode) {
ext4_dec_count(new.inode);
- new.inode->i_ctime = current_time(new.inode);
+ inode_set_ctime_current(new.inode);
}
- old.dir->i_ctime = old.dir->i_mtime = current_time(old.dir);
+ old.dir->i_mtime = inode_set_ctime_current(old.inode);
ext4_update_dx_flag(old.dir);
if (old.dir_bh) {
retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino);
@@ -4053,7 +4053,6 @@ static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
};
u8 new_file_type;
int retval;
- struct timespec64 ctime;

if ((ext4_test_inode_flag(new_dir, EXT4_INODE_PROJINHERIT) &&
!projid_eq(EXT4_I(new_dir)->i_projid,
@@ -4147,9 +4146,8 @@ static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
* Like most other Unix systems, set the ctime for inodes on a
* rename.
*/
- ctime = current_time(old.inode);
- old.inode->i_ctime = ctime;
- new.inode->i_ctime = ctime;
+ inode_set_ctime_current(old.inode);
+ inode_set_ctime_current(new.inode);
retval = ext4_mark_inode_dirty(handle, old.inode);
if (unlikely(retval))
goto end_rename;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index c94ebf704616..b54c70e1a74e 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -7103,7 +7103,7 @@ static int ext4_quota_off(struct super_block *sb, int type)
}
EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
- inode->i_mtime = inode->i_ctime = current_time(inode);
+ inode->i_mtime = inode_set_ctime_current(inode);
err = ext4_mark_inode_dirty(handle, inode);
ext4_journal_stop(handle);
out_unlock:
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 321e3a888c20..dbe54cddda3d 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -356,13 +356,13 @@ ext4_xattr_inode_hash(struct ext4_sb_info *sbi, const void *buffer, size_t size)

static u64 ext4_xattr_inode_get_ref(struct inode *ea_inode)
{
- return ((u64)ea_inode->i_ctime.tv_sec << 32) |
+ return ((u64) inode_get_ctime(ea_inode).tv_sec << 32) |
(u32) inode_peek_iversion_raw(ea_inode);
}

static void ext4_xattr_inode_set_ref(struct inode *ea_inode, u64 ref_count)
{
- ea_inode->i_ctime.tv_sec = (u32)(ref_count >> 32);
+ inode_set_ctime(ea_inode, (u32)(ref_count >> 32), 0);
inode_set_iversion_raw(ea_inode, ref_count & 0xffffffff);
}

@@ -2459,7 +2459,7 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
}
if (!error) {
ext4_xattr_update_super_block(handle, inode->i_sb);
- inode->i_ctime = current_time(inode);
+ inode_set_ctime_current(inode);
inode_inc_iversion(inode);
if (!value)
no_expand = 0;
--
2.41.0



2023-07-06 12:37:46

by Jan Kara

[permalink] [raw]
Subject: Re: [PATCH v2 42/92] ext4: convert to ctime accessor functions

On Wed 05-07-23 15:01:07, Jeff Layton wrote:
> In later patches, we're going to change how the inode's ctime field is
> used. Switch to using accessor functions instead of raw accesses of
> inode->i_ctime.
>
> Signed-off-by: Jeff Layton <[email protected]>

Some comment below:

> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 0a2d55faa095..d502b930431b 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -3823,6 +3823,27 @@ static inline int ext4_buffer_uptodate(struct buffer_head *bh)
> return buffer_uptodate(bh);
> }
>
> +static inline void ext4_inode_set_ctime(struct inode *inode, struct ext4_inode *raw_inode)
> +{
> + struct timespec64 ctime = inode_get_ctime(inode);
> +
> + if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), i_ctime_extra)) {
> + raw_inode->i_ctime = cpu_to_le32(ctime.tv_sec);
> + raw_inode->i_ctime_extra = ext4_encode_extra_time(&ctime);
> + } else {
> + raw_inode->i_ctime = cpu_to_le32(clamp_t(int32_t, ctime.tv_sec, S32_MIN, S32_MAX));
> + }
> +}
> +
> +static inline void ext4_inode_get_ctime(struct inode *inode, const struct ext4_inode *raw_inode)
> +{
> + struct timespec64 ctime = { .tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime) };
> +
> + if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), i_ctime_extra))
> + ext4_decode_extra_time(&ctime, raw_inode->i_ctime_extra);
> + inode_set_ctime(inode, ctime.tv_sec, ctime.tv_nsec);
> +}
> +

This duplication is kind of unpleasant. I was looking into it for a while
and I think we can rather do some initial cleanup (attached patch 1) and
then your conversion patch would not need to duplicate the conversion code
(see attached patch 2).

Honza
--
Jan Kara <[email protected]>
SUSE Labs, CR


Attachments:
(No filename) (1.71 kB)
0001-ext4-deduplicate-macros-for-converting-inode-timesta.patch (5.62 kB)
0002-ext4-convert-to-ctime-accessor-functions.patch (15.45 kB)
Download all attachments

2023-07-06 13:16:09

by Jeff Layton

[permalink] [raw]
Subject: Re: [PATCH v2 42/92] ext4: convert to ctime accessor functions

On Thu, 2023-07-06 at 14:36 +0200, Jan Kara wrote:
> On Wed 05-07-23 15:01:07, Jeff Layton wrote:
> > In later patches, we're going to change how the inode's ctime field is
> > used. Switch to using accessor functions instead of raw accesses of
> > inode->i_ctime.
> >
> > Signed-off-by: Jeff Layton <[email protected]>
>
> Some comment below:
>
> > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> > index 0a2d55faa095..d502b930431b 100644
> > --- a/fs/ext4/ext4.h
> > +++ b/fs/ext4/ext4.h
> > @@ -3823,6 +3823,27 @@ static inline int ext4_buffer_uptodate(struct buffer_head *bh)
> > return buffer_uptodate(bh);
> > }
> >
> > +static inline void ext4_inode_set_ctime(struct inode *inode, struct ext4_inode *raw_inode)
> > +{
> > + struct timespec64 ctime = inode_get_ctime(inode);
> > +
> > + if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), i_ctime_extra)) {
> > + raw_inode->i_ctime = cpu_to_le32(ctime.tv_sec);
> > + raw_inode->i_ctime_extra = ext4_encode_extra_time(&ctime);
> > + } else {
> > + raw_inode->i_ctime = cpu_to_le32(clamp_t(int32_t, ctime.tv_sec, S32_MIN, S32_MAX));
> > + }
> > +}
> > +
> > +static inline void ext4_inode_get_ctime(struct inode *inode, const struct ext4_inode *raw_inode)
> > +{
> > + struct timespec64 ctime = { .tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime) };
> > +
> > + if (EXT4_FITS_IN_INODE(raw_inode, EXT4_I(inode), i_ctime_extra))
> > + ext4_decode_extra_time(&ctime, raw_inode->i_ctime_extra);
> > + inode_set_ctime(inode, ctime.tv_sec, ctime.tv_nsec);
> > +}
> > +
>
> This duplication is kind of unpleasant. I was looking into it for a while
> and I think we can rather do some initial cleanup (attached patch 1) and
> then your conversion patch would not need to duplicate the conversion code
> (see attached patch 2).
>
>
>

Thanks Jan. That looks fine at first glance. I'll plan to drop my ext4
patch and replace it with these.

Cheers,
--
Jeff Layton <[email protected]>