On 2025-07-07 14:19:25, Christian Brauner wrote:

On Mon, Jul 07, 2025 at 02:05:10PM +0200, Andrey Albershteyn wrote:

quoted

On 2025-07-01 14:29:42, Christian Brauner wrote:

quoted

On Mon, Jun 30, 2025 at 06:20:10PM +0200, Andrey Albershteyn wrote:

quoted

This patchset introduced two new syscalls file_getattr() and
file_setattr(). These syscalls are similar to FS_IOC_FSSETXATTR ioctl()
except they use *at() semantics. Therefore, there's no need to open the
file to get a fd.

These syscalls allow userspace to set filesystem inode attributes on
special files. One of the usage examples is XFS quota projects.

XFS has project quotas which could be attached to a directory. All
new inodes in these directories inherit project ID set on parent
directory.

The project is created from userspace by opening and calling
FS_IOC_FSSETXATTR on each inode. This is not possible for special
files such as FIFO, SOCK, BLK etc. Therefore, some inodes are left
with empty project ID. Those inodes then are not shown in the quota
accounting but still exist in the directory. This is not critical but in
the case when special files are created in the directory with already
existing project quota, these new inodes inherit extended attributes.
This creates a mix of special files with and without attributes.
Moreover, special files with attributes don't have a possibility to
become clear or change the attributes. This, in turn, prevents userspace
from re-creating quota project on these existing files.

Only small nits I'm going to comment on that I can fix myself.
Otherwise looks great.

Hi Christian,

Let me know if you would like a new revision with all the comments
included (and your patch on file_kattr rename) or you good with
applying them while commit

It's all been in -next for a few days already. :)

Oh sorry, missed that, thanks!

-- 
- Andrey