First commit message quoted verbatim with rationable + API:

[quote]
Open-coded accesses prevent asserting they are done correctly. One
obvious aspect is locking, but significantly more can checked. For
example it can be detected when the code is clearing flags which are
already missing, or is setting flags when it is illegal (e.g., I_FREEING
when ->i_count > 0).

Given the late stage of the release cycle this patchset only aims to
hide access, it does not provide any of the checks.

Consumers can be trivially converted. Suppose flags I_A and I_B are to
be handled, then:

state = inode->i_state          => state = inode_state_read(inode)
inode->i_state |= (I_A | I_B)   => inode_state_set(inode, I_A | I_B)
inode->i_state &= ~(I_A | I_B)  => inode_state_clear(inode, I_A | I_B)
inode->i_state = I_A | I_B      => inode_state_assign(inode, I_A | I_B)
[/quote]

Right now this is one big NOP, except for READ_ONCE/WRITE_ONCE for every access.

Given this, I decided to not submit any per-fs patches. Instead, the
conversion is done in 2 parts: coccinelle and whatever which was missed.

Generated against:
https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git/commit/?h=vfs-6.18.inode.refcount.preliminaries

v6:
- rename routines:
set -> assign; add -> set; del -> clear
- update commentary in patch 3 replacing smp_store/load with smp_wmb/rmb

v5:
- drop lockdep for the time being

v4:
https://lore.kernel.org/linux-fsdevel/CAGudoHFViBUZ4TPNuLWC7qyK0v8LRwxbpZd9Mx3rHdh5GW9CrQ@mail.gmail.com/T/#m866b3b5740691de9b4008184a9a3f922dfa8e439


Mateusz Guzik (4):
  fs: provide accessors for ->i_state
  Convert the kernel to use ->i_state accessors
  Manual conversion of ->i_state uses
  fs: make plain ->i_state access fail to compile

 Documentation/filesystems/porting.rst |   2 +-
 block/bdev.c                          |   4 +-
 drivers/dax/super.c                   |   2 +-
 fs/9p/vfs_inode.c                     |   2 +-
 fs/9p/vfs_inode_dotl.c                |   2 +-
 fs/affs/inode.c                       |   2 +-
 fs/afs/dynroot.c                      |   6 +-
 fs/afs/inode.c                        |   6 +-
 fs/bcachefs/fs.c                      |   8 +-
 fs/befs/linuxvfs.c                    |   2 +-
 fs/bfs/inode.c                        |   2 +-
 fs/btrfs/inode.c                      |  10 +--
 fs/buffer.c                           |   4 +-
 fs/ceph/cache.c                       |   2 +-
 fs/ceph/crypto.c                      |   4 +-
 fs/ceph/file.c                        |   4 +-
 fs/ceph/inode.c                       |  28 +++---
 fs/coda/cnode.c                       |   4 +-
 fs/cramfs/inode.c                     |   2 +-
 fs/crypto/keyring.c                   |   2 +-
 fs/crypto/keysetup.c                  |   2 +-
 fs/dcache.c                           |   8 +-
 fs/drop_caches.c                      |   2 +-
 fs/ecryptfs/inode.c                   |   6 +-
 fs/efs/inode.c                        |   2 +-
 fs/erofs/inode.c                      |   2 +-
 fs/ext2/inode.c                       |   2 +-
 fs/ext4/inode.c                       |  10 +--
 fs/ext4/orphan.c                      |   4 +-
 fs/f2fs/data.c                        |   2 +-
 fs/f2fs/inode.c                       |   2 +-
 fs/f2fs/namei.c                       |   4 +-
 fs/f2fs/super.c                       |   2 +-
 fs/freevxfs/vxfs_inode.c              |   2 +-
 fs/fs-writeback.c                     | 123 +++++++++++++-------------
 fs/fuse/inode.c                       |   4 +-
 fs/gfs2/file.c                        |   2 +-
 fs/gfs2/glops.c                       |   2 +-
 fs/gfs2/inode.c                       |   4 +-
 fs/gfs2/ops_fstype.c                  |   2 +-
 fs/hfs/btree.c                        |   2 +-
 fs/hfs/inode.c                        |   2 +-
 fs/hfsplus/super.c                    |   2 +-
 fs/hostfs/hostfs_kern.c               |   2 +-
 fs/hpfs/dir.c                         |   2 +-
 fs/hpfs/inode.c                       |   2 +-
 fs/inode.c                            | 100 ++++++++++-----------
 fs/isofs/inode.c                      |   2 +-
 fs/jffs2/fs.c                         |   4 +-
 fs/jfs/file.c                         |   4 +-
 fs/jfs/inode.c                        |   2 +-
 fs/jfs/jfs_txnmgr.c                   |   2 +-
 fs/kernfs/inode.c                     |   2 +-
 fs/libfs.c                            |   6 +-
 fs/minix/inode.c                      |   2 +-
 fs/namei.c                            |   8 +-
 fs/netfs/misc.c                       |   8 +-
 fs/netfs/read_single.c                |   6 +-
 fs/nfs/inode.c                        |   2 +-
 fs/nfs/pnfs.c                         |   2 +-
 fs/nfsd/vfs.c                         |   2 +-
 fs/nilfs2/cpfile.c                    |   2 +-
 fs/nilfs2/dat.c                       |   2 +-
 fs/nilfs2/ifile.c                     |   2 +-
 fs/nilfs2/inode.c                     |  10 +--
 fs/nilfs2/sufile.c                    |   2 +-
 fs/notify/fsnotify.c                  |   2 +-
 fs/ntfs3/inode.c                      |   2 +-
 fs/ocfs2/dlmglue.c                    |   2 +-
 fs/ocfs2/inode.c                      |  10 +--
 fs/omfs/inode.c                       |   2 +-
 fs/openpromfs/inode.c                 |   2 +-
 fs/orangefs/inode.c                   |   2 +-
 fs/orangefs/orangefs-utils.c          |   6 +-
 fs/overlayfs/dir.c                    |   2 +-
 fs/overlayfs/inode.c                  |   6 +-
 fs/overlayfs/util.c                   |  10 +--
 fs/pipe.c                             |   2 +-
 fs/qnx4/inode.c                       |   2 +-
 fs/qnx6/inode.c                       |   2 +-
 fs/quota/dquot.c                      |   2 +-
 fs/romfs/super.c                      |   2 +-
 fs/smb/client/cifsfs.c                |   2 +-
 fs/smb/client/inode.c                 |  14 +--
 fs/squashfs/inode.c                   |   2 +-
 fs/sync.c                             |   2 +-
 fs/ubifs/file.c                       |   2 +-
 fs/ubifs/super.c                      |   2 +-
 fs/udf/inode.c                        |   2 +-
 fs/ufs/inode.c                        |   2 +-
 fs/xfs/scrub/common.c                 |   2 +-
 fs/xfs/scrub/inode_repair.c           |   2 +-
 fs/xfs/scrub/parent.c                 |   2 +-
 fs/xfs/xfs_bmap_util.c                |   2 +-
 fs/xfs/xfs_health.c                   |   4 +-
 fs/xfs/xfs_icache.c                   |   6 +-
 fs/xfs/xfs_inode.c                    |   6 +-
 fs/xfs/xfs_inode_item.c               |   4 +-
 fs/xfs/xfs_iops.c                     |   2 +-
 fs/xfs/xfs_reflink.h                  |   2 +-
 fs/zonefs/super.c                     |   4 +-
 include/linux/backing-dev.h           |   7 +-
 include/linux/fs.h                    |  42 ++++++++-
 include/linux/writeback.h             |   4 +-
 include/trace/events/writeback.h      |   8 +-
 mm/backing-dev.c                      |   2 +-
 security/landlock/fs.c                |   2 +-
 107 files changed, 345 insertions(+), 307 deletions(-)

-- 
2.43.0

On Tue, Sep 23, 2025 at 12:47:06PM +0200, Mateusz Guzik wrote:
> First commit message quoted verbatim with rationable + API:
> 
> [quote]
> Open-coded accesses prevent asserting they are done correctly. One
> obvious aspect is locking, but significantly more can checked. For
> example it can be detected when the code is clearing flags which are
> already missing, or is setting flags when it is illegal (e.g., I_FREEING
> when ->i_count > 0).
> 
> Given the late stage of the release cycle this patchset only aims to
> hide access, it does not provide any of the checks.
> 
> Consumers can be trivially converted. Suppose flags I_A and I_B are to
> be handled, then:
> 
> state = inode->i_state          => state = inode_state_read(inode)
> inode->i_state |= (I_A | I_B)   => inode_state_set(inode, I_A | I_B)
> inode->i_state &= ~(I_A | I_B)  => inode_state_clear(inode, I_A | I_B)
> inode->i_state = I_A | I_B      => inode_state_assign(inode, I_A | I_B)
> [/quote]
> 
> Right now this is one big NOP, except for READ_ONCE/WRITE_ONCE for every access.
> 
> Given this, I decided to not submit any per-fs patches. Instead, the
> conversion is done in 2 parts: coccinelle and whatever which was missed.
> 
> Generated against:
> https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git/commit/?h=vfs-6.18.inode.refcount.preliminaries

Much simpler and nicer than the earlier versions. Looks good.

Reviewed-by: Dave Chinner <dchinner@redhat.com>

-- 
Dave Chinner
david@fromorbit.com

On Tue 23-09-25 12:47:06, Mateusz Guzik wrote:
> First commit message quoted verbatim with rationable + API:
> 
> [quote]
> Open-coded accesses prevent asserting they are done correctly. One
> obvious aspect is locking, but significantly more can checked. For
> example it can be detected when the code is clearing flags which are
> already missing, or is setting flags when it is illegal (e.g., I_FREEING
> when ->i_count > 0).
> 
> Given the late stage of the release cycle this patchset only aims to
> hide access, it does not provide any of the checks.
> 
> Consumers can be trivially converted. Suppose flags I_A and I_B are to
> be handled, then:
> 
> state = inode->i_state          => state = inode_state_read(inode)
> inode->i_state |= (I_A | I_B)   => inode_state_set(inode, I_A | I_B)
> inode->i_state &= ~(I_A | I_B)  => inode_state_clear(inode, I_A | I_B)
> inode->i_state = I_A | I_B      => inode_state_assign(inode, I_A | I_B)
> [/quote]
> 
> Right now this is one big NOP, except for READ_ONCE/WRITE_ONCE for every access.
> 
> Given this, I decided to not submit any per-fs patches. Instead, the
> conversion is done in 2 parts: coccinelle and whatever which was missed.

This looks good to me now. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> 
> Generated against:
> https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git/commit/?h=vfs-6.18.inode.refcount.preliminaries
> 
> v6:
> - rename routines:
> set -> assign; add -> set; del -> clear
> - update commentary in patch 3 replacing smp_store/load with smp_wmb/rmb
> 
> v5:
> - drop lockdep for the time being
> 
> v4:
> https://lore.kernel.org/linux-fsdevel/CAGudoHFViBUZ4TPNuLWC7qyK0v8LRwxbpZd9Mx3rHdh5GW9CrQ@mail.gmail.com/T/#m866b3b5740691de9b4008184a9a3f922dfa8e439
> 
> 
> Mateusz Guzik (4):
>   fs: provide accessors for ->i_state
>   Convert the kernel to use ->i_state accessors
>   Manual conversion of ->i_state uses
>   fs: make plain ->i_state access fail to compile
> 
>  Documentation/filesystems/porting.rst |   2 +-
>  block/bdev.c                          |   4 +-
>  drivers/dax/super.c                   |   2 +-
>  fs/9p/vfs_inode.c                     |   2 +-
>  fs/9p/vfs_inode_dotl.c                |   2 +-
>  fs/affs/inode.c                       |   2 +-
>  fs/afs/dynroot.c                      |   6 +-
>  fs/afs/inode.c                        |   6 +-
>  fs/bcachefs/fs.c                      |   8 +-
>  fs/befs/linuxvfs.c                    |   2 +-
>  fs/bfs/inode.c                        |   2 +-
>  fs/btrfs/inode.c                      |  10 +--
>  fs/buffer.c                           |   4 +-
>  fs/ceph/cache.c                       |   2 +-
>  fs/ceph/crypto.c                      |   4 +-
>  fs/ceph/file.c                        |   4 +-
>  fs/ceph/inode.c                       |  28 +++---
>  fs/coda/cnode.c                       |   4 +-
>  fs/cramfs/inode.c                     |   2 +-
>  fs/crypto/keyring.c                   |   2 +-
>  fs/crypto/keysetup.c                  |   2 +-
>  fs/dcache.c                           |   8 +-
>  fs/drop_caches.c                      |   2 +-
>  fs/ecryptfs/inode.c                   |   6 +-
>  fs/efs/inode.c                        |   2 +-
>  fs/erofs/inode.c                      |   2 +-
>  fs/ext2/inode.c                       |   2 +-
>  fs/ext4/inode.c                       |  10 +--
>  fs/ext4/orphan.c                      |   4 +-
>  fs/f2fs/data.c                        |   2 +-
>  fs/f2fs/inode.c                       |   2 +-
>  fs/f2fs/namei.c                       |   4 +-
>  fs/f2fs/super.c                       |   2 +-
>  fs/freevxfs/vxfs_inode.c              |   2 +-
>  fs/fs-writeback.c                     | 123 +++++++++++++-------------
>  fs/fuse/inode.c                       |   4 +-
>  fs/gfs2/file.c                        |   2 +-
>  fs/gfs2/glops.c                       |   2 +-
>  fs/gfs2/inode.c                       |   4 +-
>  fs/gfs2/ops_fstype.c                  |   2 +-
>  fs/hfs/btree.c                        |   2 +-
>  fs/hfs/inode.c                        |   2 +-
>  fs/hfsplus/super.c                    |   2 +-
>  fs/hostfs/hostfs_kern.c               |   2 +-
>  fs/hpfs/dir.c                         |   2 +-
>  fs/hpfs/inode.c                       |   2 +-
>  fs/inode.c                            | 100 ++++++++++-----------
>  fs/isofs/inode.c                      |   2 +-
>  fs/jffs2/fs.c                         |   4 +-
>  fs/jfs/file.c                         |   4 +-
>  fs/jfs/inode.c                        |   2 +-
>  fs/jfs/jfs_txnmgr.c                   |   2 +-
>  fs/kernfs/inode.c                     |   2 +-
>  fs/libfs.c                            |   6 +-
>  fs/minix/inode.c                      |   2 +-
>  fs/namei.c                            |   8 +-
>  fs/netfs/misc.c                       |   8 +-
>  fs/netfs/read_single.c                |   6 +-
>  fs/nfs/inode.c                        |   2 +-
>  fs/nfs/pnfs.c                         |   2 +-
>  fs/nfsd/vfs.c                         |   2 +-
>  fs/nilfs2/cpfile.c                    |   2 +-
>  fs/nilfs2/dat.c                       |   2 +-
>  fs/nilfs2/ifile.c                     |   2 +-
>  fs/nilfs2/inode.c                     |  10 +--
>  fs/nilfs2/sufile.c                    |   2 +-
>  fs/notify/fsnotify.c                  |   2 +-
>  fs/ntfs3/inode.c                      |   2 +-
>  fs/ocfs2/dlmglue.c                    |   2 +-
>  fs/ocfs2/inode.c                      |  10 +--
>  fs/omfs/inode.c                       |   2 +-
>  fs/openpromfs/inode.c                 |   2 +-
>  fs/orangefs/inode.c                   |   2 +-
>  fs/orangefs/orangefs-utils.c          |   6 +-
>  fs/overlayfs/dir.c                    |   2 +-
>  fs/overlayfs/inode.c                  |   6 +-
>  fs/overlayfs/util.c                   |  10 +--
>  fs/pipe.c                             |   2 +-
>  fs/qnx4/inode.c                       |   2 +-
>  fs/qnx6/inode.c                       |   2 +-
>  fs/quota/dquot.c                      |   2 +-
>  fs/romfs/super.c                      |   2 +-
>  fs/smb/client/cifsfs.c                |   2 +-
>  fs/smb/client/inode.c                 |  14 +--
>  fs/squashfs/inode.c                   |   2 +-
>  fs/sync.c                             |   2 +-
>  fs/ubifs/file.c                       |   2 +-
>  fs/ubifs/super.c                      |   2 +-
>  fs/udf/inode.c                        |   2 +-
>  fs/ufs/inode.c                        |   2 +-
>  fs/xfs/scrub/common.c                 |   2 +-
>  fs/xfs/scrub/inode_repair.c           |   2 +-
>  fs/xfs/scrub/parent.c                 |   2 +-
>  fs/xfs/xfs_bmap_util.c                |   2 +-
>  fs/xfs/xfs_health.c                   |   4 +-
>  fs/xfs/xfs_icache.c                   |   6 +-
>  fs/xfs/xfs_inode.c                    |   6 +-
>  fs/xfs/xfs_inode_item.c               |   4 +-
>  fs/xfs/xfs_iops.c                     |   2 +-
>  fs/xfs/xfs_reflink.h                  |   2 +-
>  fs/zonefs/super.c                     |   4 +-
>  include/linux/backing-dev.h           |   7 +-
>  include/linux/fs.h                    |  42 ++++++++-
>  include/linux/writeback.h             |   4 +-
>  include/trace/events/writeback.h      |   8 +-
>  mm/backing-dev.c                      |   2 +-
>  security/landlock/fs.c                |   2 +-
>  107 files changed, 345 insertions(+), 307 deletions(-)
> 
> -- 
> 2.43.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

On Tue, 23 Sep 2025 12:47:06 +0200, Mateusz Guzik wrote:
> First commit message quoted verbatim with rationable + API:
> 
> [quote]
> Open-coded accesses prevent asserting they are done correctly. One
> obvious aspect is locking, but significantly more can checked. For
> example it can be detected when the code is clearing flags which are
> already missing, or is setting flags when it is illegal (e.g., I_FREEING
> when ->i_count > 0).
> 
> [...]

Applied to the vfs-6.19.inode branch of the vfs/vfs.git tree.
Patches in the vfs-6.19.inode branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs-6.19.inode

[1/4] fs: provide accessors for ->i_state
      https://git.kernel.org/vfs/vfs/c/e9d1a9abd054
[2/4] Convert the kernel to use ->i_state accessors
      https://git.kernel.org/vfs/vfs/c/67d2f3e3d033
[3/4] Manual conversion of ->i_state uses
      https://git.kernel.org/vfs/vfs/c/b8173a2f1a0a
[4/4] fs: make plain ->i_state access fail to compile
      https://git.kernel.org/vfs/vfs/c/3c2b8d921da8

This was a stripped down version (no lockdep) in hopes of getting into
6.18. It also happens to come with some renames.

Given that the inclusion did not happen, I'm going to send a rebased
and updated with new names variant but with lockdep.

So the routines will be:
inode_state_read_once
inode_state_read

inode_state_set{,_raw}
inode_state_clear{,_raw}
inode_state_assign{,_raw}

Probably way later today or tomorrow.

On Mon, Sep 29, 2025 at 11:30 AM Christian Brauner <brauner@kernel.org> wrote:
>
> On Tue, 23 Sep 2025 12:47:06 +0200, Mateusz Guzik wrote:
> > First commit message quoted verbatim with rationable + API:
> >
> > [quote]
> > Open-coded accesses prevent asserting they are done correctly. One
> > obvious aspect is locking, but significantly more can checked. For
> > example it can be detected when the code is clearing flags which are
> > already missing, or is setting flags when it is illegal (e.g., I_FREEING
> > when ->i_count > 0).
> >
> > [...]
>
> Applied to the vfs-6.19.inode branch of the vfs/vfs.git tree.
> Patches in the vfs-6.19.inode branch should appear in linux-next soon.
>
> Please report any outstanding bugs that were missed during review in a
> new review to the original patch series allowing us to drop it.
>
> It's encouraged to provide Acked-bys and Reviewed-bys even though the
> patch has now been applied. If possible patch trailers will be updated.
>
> Note that commit hashes shown below are subject to change due to rebase,
> trailer updates or similar. If in doubt, please check the listed branch.
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
> branch: vfs-6.19.inode
>
> [1/4] fs: provide accessors for ->i_state
>       https://git.kernel.org/vfs/vfs/c/e9d1a9abd054
> [2/4] Convert the kernel to use ->i_state accessors
>       https://git.kernel.org/vfs/vfs/c/67d2f3e3d033
> [3/4] Manual conversion of ->i_state uses
>       https://git.kernel.org/vfs/vfs/c/b8173a2f1a0a
> [4/4] fs: make plain ->i_state access fail to compile
>       https://git.kernel.org/vfs/vfs/c/3c2b8d921da8

On Mon, Sep 29, 2025 at 02:56:23PM +0200, Mateusz Guzik wrote:
> This was a stripped down version (no lockdep) in hopes of getting into
> 6.18. It also happens to come with some renames.

That was not obvious at all and I didn't read that anywhere in the
commit messages?

Anyway, please resend on top of vfs-6.19.inode where I applied your
other patches! Thank you!

On Mon, Oct 6, 2025 at 1:38 PM Christian Brauner <brauner@kernel.org> wrote:
>
> On Mon, Sep 29, 2025 at 02:56:23PM +0200, Mateusz Guzik wrote:
> > This was a stripped down version (no lockdep) in hopes of getting into
> > 6.18. It also happens to come with some renames.
>
> That was not obvious at all and I didn't read that anywhere in the
> commit messages?
>

Well I thought I made it clear in the updated cover letter, we can
chalk it up to miscommunication. Shit happens.

> Anyway, please resend on top of vfs-6.19.inode where I applied your
> other patches! Thank you!

I rebased the patchset on top of vfs-6.19.inode and got a build failure:

fs/ocfs2/super.c:132:27: error: ‘inode_just_drop’ undeclared here (not
in a function)
  132 |         .drop_inode     = inode_just_drop,
      |                           ^~~~~~~~~~~~~~~

and sure enough the commit renaming that helper is missing. Can you
please rebase the branch?

> I rebased the patchset on top of vfs-6.19.inode and got a build failure:
> 
> fs/ocfs2/super.c:132:27: error: ‘inode_just_drop’ undeclared here (not
> in a function)
>   132 |         .drop_inode     = inode_just_drop,
>       |                           ^~~~~~~~~~~~~~~
> 
> and sure enough the commit renaming that helper is missing. Can you
> please rebase the branch?

Done. Thanks!