linux/fs/overlayfs
Christian Brauner a15506eac9 ovl: use ovl_do_notify_change() wrapper
Introduce ovl_do_notify_change() as a simple wrapper around
notify_change() to support idmapped layers. The helper mirrors other
ovl_do_*() helpers that operate on the upper layers.

When changing ownership of an upper object the intended ownership needs
to be mapped according to the upper layer's idmapping. This mapping is
the inverse to the mapping applied when copying inode information from
an upper layer to the corresponding overlay inode. So e.g., when an
upper mount maps files that are stored on-disk as owned by id 1001 to
1000 this means that calling stat on this object from an idmapped mount
will report the file as being owned by id 1000. Consequently in order to
change ownership of an object in this filesystem so it appears as being
owned by id 1000 in the upper idmapped layer it needs to store id 1001
on disk. The mnt mapping helpers take care of this.

All idmapping helpers are nops when no idmapped base layers are used.

Cc: <linux-unionfs@vger.kernel.org>
Tested-by: Giuseppe Scrivano <gscrivan@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-04-28 16:31:11 +02:00
..
copy_up.c ovl: use ovl_do_notify_change() wrapper 2022-04-28 16:31:11 +02:00
dir.c ovl: use ovl_do_notify_change() wrapper 2022-04-28 16:31:11 +02:00
export.c ovl: fix uninitialized pointer read in ovl_lookup_real_one() 2021-08-10 10:21:30 +02:00
file.c ovl: pass layer mnt to ovl_open_realfile() 2022-04-28 16:31:11 +02:00
inode.c ovl: use ovl_do_notify_change() wrapper 2022-04-28 16:31:11 +02:00
Kconfig docs: fix broken references to text files 2020-04-20 15:35:59 -06:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
namei.c ovl: use wrappers to all vfs_*xattr() calls 2022-04-28 16:31:10 +02:00
overlayfs.h ovl: use ovl_do_notify_change() wrapper 2022-04-28 16:31:11 +02:00
ovl_entry.h ovl: add ovl_upper_mnt_userns() wrapper 2022-04-28 16:31:11 +02:00
readdir.c ovl: pass ofs to creation operations 2022-04-28 16:31:10 +02:00
super.c ovl: use ovl_do_notify_change() wrapper 2022-04-28 16:31:11 +02:00
util.c ovl: pass layer mnt to ovl_open_realfile() 2022-04-28 16:31:11 +02:00