tmpfs: add support for multigrain timestamps

Enable multigrain timestamps, which should ensure that there is an
apparent change to the timestamp whenever it has been written after
being actively observed via getattr.

tmpfs only requires the FS_MGTIME flag.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230807-mgctime-v7-10-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: add infrastructure for multigrain timestamps

The VFS always uses coarse-grained timestamps when updating the ctime
and mtime after a change. This has the benefit of allowing filesystems
to optimize away a lot metadata updates, down to around 1 per jiffy,
even when a file is under heavy writes.

Unfortunately, this has always been an issue when we're exporting via
NFSv3, which relies on timestamps to validate caches. A lot of changes
can happen in a jiffy, so timestamps aren't sufficient to help the
client decide to invalidate the cache. Even with NFSv4, a lot of
exported filesystems don't properly support a change attribute and are
subject to the same problems with timestamp granularity. Other
applications have similar issues with timestamps (e.g backup
applications).

If we were to always use fine-grained timestamps, that would improve the
situation, but that becomes rather expensive, as the underlying
filesystem would have to log a lot more metadata updates.

What we need is a way to only use fine-grained timestamps when they are
being actively queried.

POSIX generally mandates that when the the mtime changes, the ctime must
also change. The kernel always stores normalized ctime values, so only
the first 30 bits of the tv_nsec field are ever used.

Use the 31st bit of the ctime tv_nsec field to indicate that something
has queried the inode for the mtime or ctime. When this flag is set,
on the next mtime or ctime update, the kernel will fetch a fine-grained
timestamp instead of the usual coarse-grained one.

Filesytems can opt into this behavior by setting the FS_MGTIME flag in
the fstype. Filesystems that don't set this flag will continue to use
coarse-grained timestamps.

Later patches will convert individual filesystems to use the new
infrastructure.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230807-mgctime-v7-9-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: drop the timespec64 argument from update_time

Now that all of the update_time operations are prepared for it, we can
drop the timespec64 argument from the update_time operation. Do that and
remove it from some associated functions like inode_update_time and
inode_needs_update_time.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230807-mgctime-v7-8-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

xfs: have xfs_vn_update_time gets its own timestamp

In later patches we're going to drop the "now" parameter from the
update_time operation. Prepare XFS for this by reworking how it fetches
timestamps and sets them in the inode. Ensure that we update the ctime
even if only S_MTIME is set.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230807-mgctime-v7-7-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fat: make fat_update_time get its own timestamp

In later patches, we're going to drop the "now" parameter from the
update_time operation. Fix fat_update_time to fetch its own timestamp.
It turns out that this is easily done by just passing a NULL timestamp
pointer to fat_truncate_time.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Frank Sorenson <sorenson@redhat.com>
Message-Id: <20230810-ctime-fat-v1-2-327598fd1de8@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fat: remove i_version handling from fat_update_time

commit 6bb885ecd746 (fat: add functions to update and truncate
timestamps appropriately") added an update_time routine for fat. That
patch added a section for handling the S_VERSION bit, even though FAT
doesn't enable SB_I_VERSION and the S_VERSION bit will never be set when
calling it.

Remove the section for handling S_VERSION since it's effectively dead
code, and will be problematic vs. future changes.

Cc: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Frank Sorenson <sorenson@redhat.com>
Message-Id: <20230810-ctime-fat-v1-1-327598fd1de8@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ubifs: have ubifs_update_time use inode_update_timestamps

In later patches, we're going to drop the "now" parameter from the
update_time operation. Prepare ubifs for this, by having it use the new
inode_update_timestamps helper.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230807-mgctime-v7-6-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

btrfs: have it use inode_update_timestamps

In later patches, we're going to drop the "now" argument from the
update_time operation. Have btrfs_update_time use the new
inode_update_timestamps helper to fetch a new timestamp and update it
properly.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230807-mgctime-v7-4-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: drop the timespec64 arg from generic_update_time

In future patches we're going to change how the ctime is updated
to keep track of when it has been queried. The way that the update_time
operation works (and a lot of its callers) make this difficult, since
they grab a timestamp early and then pass it down to eventually be
copied into the inode.

All of the existing update_time callers pass in the result of
current_time() in some fashion. Drop the "time" parameter from
generic_update_time, and rework it to fetch its own timestamp.

This change means that an update_time could fetch a different timestamp
than was seen in inode_needs_update_time. update_time is only ever
called with one of two flag combinations: Either S_ATIME is set, or
S_MTIME|S_CTIME|S_VERSION are set.

With this change we now treat the flags argument as an indicator that
some value needed to be updated when last checked, rather than an
indication to update specific timestamps.

Rework the logic for updating the timestamps and put it in a new
inode_update_timestamps helper that other update_time routines can use.
S_ATIME is as treated as we always have, but if any of the other three
are set, then we attempt to update all three.

Also, some callers of generic_update_time need to know what timestamps
were actually updated. Change it to return an S_* flag mask to indicate
that and rework the callers to expect it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230807-mgctime-v7-3-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: pass the request_mask to generic_fillattr

generic_fillattr just fills in the entire stat struct indiscriminately
today, copying data from the inode. There is at least one attribute
(STATX_CHANGE_COOKIE) that can have side effects when it is reported,
and we're looking at adding more with the addition of multigrain
timestamps.

Add a request_mask argument to generic_fillattr and have most callers
just pass in the value that is passed to getattr. Have other callers
(e.g. ksmbd) just pass in STATX_BASIC_STATS. Also move the setting of
STATX_CHANGE_COOKIE into generic_fillattr.

Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Paulo Alcantara (SUSE)" <pc@manguebit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230807-mgctime-v7-2-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: remove silly warning from current_time

An inode with no superblock? Unpossible!

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230807-mgctime-v7-1-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

gfs2: fix timestamp handling on quota inodes

While these aren't generally visible from userland, it's best to be
consistent with timestamp handling. When adjusting the quota, update the
mtime and ctime like we would with a write operation on any other inode,
and avoid updating the atime which should only be done for reads.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Message-Id: <20230713135249.153796-1-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: rename i_ctime field to __i_ctime

Now that everything in-tree is converted to use the accessor functions,
rename the i_ctime field in the inode to discourage direct access.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705185812.579118-4-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

selinux: 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.

Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-89-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

security: 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.

Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-88-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

apparmor: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-87-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

sunrpc: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-86-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

shmem: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-85-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

bpf: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-84-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

mqueue: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-83-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

linux: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-82-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

zonefs: 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.

Acked-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-81-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

xfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-80-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

vboxsf: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-79-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ufs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-78-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

udf: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-77-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ubifs: 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 <jlayton@kernel.org>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Message-Id: <20230705190309.579783-76-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

tracefs: 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 <jlayton@kernel.org>
Acked-by: "Steven Rostedt (Google)" <rostedt@goodmis.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-75-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

sysv: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-74-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

squashfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-73-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

smb: 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.

Acked-by: Tom Talpey <tom@talpey.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Steve French <stfrench@microsoft.com>
Message-Id: <20230705190309.579783-72-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

romfs: 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 <jlayton@kernel.org>
Message-Id: <20230705190309.579783-71-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

reiserfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-70-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ramfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-69-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

qnx6: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-68-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

qnx4: 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.

Acked-by: Anders Larsen <al@alarsen.net>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-67-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

pstore: 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.

Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-66-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

procfs: 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.

Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-65-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

overlayfs: 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.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-64-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

orangefs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-63-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

openpromfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-62-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

omfs: 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.

Acked-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-61-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ocfs2: 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 <jlayton@kernel.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-60-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ntfs3: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-59-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ntfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-58-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

nilfs2: 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.

Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-57-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

nfsd: 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.

Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-56-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

nfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-55-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

kernfs: 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.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-54-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

jfs: 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.

Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-53-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

jffs2: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-52-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

isofs: 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 <jlayton@kernel.org>
Message-Id: <20230705190309.579783-51-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

hugetlbfs: 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 <jlayton@kernel.org>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-50-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

hpfs: 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 <jlayton@kernel.org>
Message-Id: <20230705190309.579783-49-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

hostfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-48-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

hfsplus: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-47-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

hfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-46-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

gfs2: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-45-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fuse: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-44-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

freevxfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-43-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fat: 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 <jlayton@kernel.org>
Message-Id: <20230705190309.579783-42-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

f2fs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-41-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

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 <jlayton@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-40-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ext2: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-39-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

exfat: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-38-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

erofs: 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.

Acked-by: Gao Xiang <xiang@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-37-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

efs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-36-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

efivarfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-35-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ecryptfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-34-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

devpts: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-33-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

debugfs: 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.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-32-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

cramfs: 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.

Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-31-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

configfs: 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 <jlayton@kernel.org>
Acked-by: Joel Becker <jlbec@evilplan.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-30-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

coda: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-29-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ceph: 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.

Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-28-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

btrfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-27-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

bfs: 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 <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-26-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

befs: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-25-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

autofs: 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.

Reviewed-by: Ian Kent <raven@themaw.net>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-24-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-23-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

afs: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-22-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

affs: 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.

Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-21-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

adfs: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-20-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

9p: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-19-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

usb: 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.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-18-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ibm: 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.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-17-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

infiniband: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-16-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

binderfs: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-15-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

s390: 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.

Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-14-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

spufs: 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.

Acked-by: Jeremy Kerr <jk@ozlabs.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Message-Id: <20230705190309.579783-13-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

reiserfs: convert to simple_rename_timestamp

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-12-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ntfs3: convert to simple_rename_timestamp

A rename potentially involves updating 4 different inode timestamps.
Convert to the new simple_rename_timestamp helper function.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-11-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

exfat: convert to simple_rename_timestamp

A rename potentially involves updating 4 different inode timestamps.
Convert to the new simple_rename_timestamp helper function.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-10-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

shmem: convert to simple_rename_timestamp

A rename potentially involves updating 4 different inode timestamps.
Convert to the new simple_rename_timestamp helper function.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-9-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ubifs: convert to simple_rename_timestamp

A rename potentially involves updating 4 different inode timestamps.
Convert to the new simple_rename_timestamp helper function.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Message-Id: <20230705190309.579783-8-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

btrfs: convert to simple_rename_timestamp

A rename potentially involves updating 4 different inode timestamps.
Convert to the new simple_rename_timestamp helper function.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-7-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: new helper: simple_rename_timestamp

A rename potentially involves updating 4 different inode timestamps. Add
a function that handles the details sanely, and convert the libfs.c
callers to use it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705185812.579118-3-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: add ctime accessors infrastructure

struct timespec64 has unused bits in the tv_nsec field that can be used
for other purposes. In future patches, we're going to change how the
inode->i_ctime is accessed in certain inodes in order to make use of
them. In order to do that safely though, we'll need to eradicate raw
accesses of the inode->i_ctime field from the kernel.

Add new accessor functions for the ctime that we use to replace them.

Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Message-Id: <20230705185812.579118-2-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

cifs: update the ctime on a partial page write

POSIX says:

    "Upon successful completion, where nbyte is greater than 0, write()
     shall mark for update the last data modification and last file status
     change timestamps of the file..."

Add the missing ctime update.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Steve French <stfrench@microsoft.com>
Message-Id: <20230705190309.579783-6-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

apparmor: update ctime whenever the mtime changes on an inode

In general, when updating the mtime on an inode, one must also update
the ctime. Add the missing ctime updates.

Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-5-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>