[PATCH v2 0/3] Test file_getattr and file_setattr syscalls

[Andrey Albershteyn <aalbersh@redhat.com>]

Add a test to check basic functionallity of file_getattr() and
file_setattr() syscalls. These syscalls are used to get/set filesystem
inode attributes (think of FS_IOC_SETFSXATTR ioctl()). The difference
from ioctl() is that these syscalls use *at() semantics and can be
called on any file without opening it, including special ones.

For XFS, with the use of these syscalls, xfs_quota now can
manipulate quota on special files such as sockets. Add a test to
check that special files are counted, which wasn't true before.

To: fstests@vger.kernel.org
Cc: zlang@redhat.com
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-xfs@vger.kernel.org

Signed-off-by: Andrey Albershteyn <aalbersh@kernel.org>
---
Changes in v2:
- Improve help message for file_attr
- Refactor file_attr.c
- Drop _wants_*_commit
- Link to v1: https://lore.kernel.org/r/20250808-xattrat-syscall-v1-0-6a09c4f37f10@kernel.org

---
Andrey Albershteyn (3):
      file_attr: introduce program to set/get fsxattr
      generic: introduce test to test file_getattr/file_setattr syscalls
      xfs: test quota's project ID on special files

 .gitignore             |   1 +
 configure.ac           |   1 +
 include/builddefs.in   |   1 +
 m4/package_libcdev.m4  |  16 +++
 src/Makefile           |   5 +
 src/file_attr.c        | 268 +++++++++++++++++++++++++++++++++++++++++++++++++
 tests/generic/2000     | 109 ++++++++++++++++++++
 tests/generic/2000.out |  37 +++++++
 tests/xfs/2000         |  73 ++++++++++++++
 tests/xfs/2000.out     |  15 +++
 10 files changed, 526 insertions(+)
---
base-commit: 3d57f543ae0c149eb460574dcfb8d688aeadbfff
change-id: 20250317-xattrat-syscall-ee8f5e2d6e18

Best regards,
-- 
Andrey Albershteyn <aalbersh@kernel.org>