Jan, Following up on the plan laid out in this discussion, this patch set implements the simpler and less controversial part of the plan to enable AT_HANDLE_FID for all filesystems. One filesystem that I tested which gained FAN_REPORT_FID support is 9p, but there are many other filesystem for whom fanotify will become mostly inotify drop-in replacement after this change. Since the main goal of this change is to progress fanotify towards being an inotify drop-in replacement, support for FAN_REPORT_FID with sb/mount mark is at lower priority. Because I think that support for FAN_REPORT_FID with sb/mount mark is controversial with non-decodeable (AT_HANDLE_FID) file handles, I have also disabled this feature that was added in v6.6-rc1 to ovelrayfs. If you agree to this retroactive change, the path #1 should be fast tracked into v6.6. The rest of the changes should probably go in via the vfs tree after review from you and nfsd maintainers. Thanks, Amir. [1] https://lore.kernel.org/r/20230920110429.f4wkfuls73pd55pv@quack3/ Amir Goldstein (5): fanotify: limit reporting of event with non-decodeable file handles exportfs: add helpers to check if filesystem can encode/decode file handles exportfs: make ->encode_fh() a mandatory method for NFS export exportfs: define FILEID_INO64_GEN* file handle types exportfs: support encoding non-decodeable file handles by default Documentation/filesystems/nfs/exporting.rst | 7 +-- Documentation/filesystems/porting.rst | 9 ++++ fs/affs/namei.c | 1 + fs/befs/linuxvfs.c | 1 + fs/efs/super.c | 1 + fs/erofs/super.c | 1 + fs/exportfs/expfs.c | 50 +++++++++++++++------ fs/ext2/super.c | 1 + fs/ext4/super.c | 1 + fs/f2fs/super.c | 1 + fs/fat/nfs.c | 1 + fs/fhandle.c | 6 +-- fs/fuse/inode.c | 7 +-- fs/jffs2/super.c | 1 + fs/jfs/super.c | 1 + fs/nfsd/export.c | 3 +- fs/notify/fanotify/fanotify_user.c | 25 +++++++---- fs/ntfs/namei.c | 1 + fs/ntfs3/super.c | 1 + fs/overlayfs/util.c | 2 +- fs/smb/client/export.c | 9 ++-- fs/squashfs/export.c | 1 + fs/ufs/super.c | 1 + include/linux/exportfs.h | 46 ++++++++++++++++++- 24 files changed, 133 insertions(+), 45 deletions(-) -- 2.34.1