Christian, The grand plan is to be able to use fanotify with FAN_REPORT_FID as a drop-in replacement for inotify, but with current upstream, inotify is supported on all the filesystems and FAN_REPORT_FID only on a few. Making all filesystem support FAN_REPORT_FID requires that all filesystems will: 1. Support for AT_HANDLE_FID file handles 2. Report non-zero f_fsid This patch set takes care of the first requirement. Patches were reviewed by Jan and the nfsd maintainers. I have another patch in review [2] for adding non-zero f_fsid to many simple filesystems, but it is independent of this patch set, so no reason to couple them together. Note that patch #2 touches many filesystems due to vfs API change, requiring an explicit ->encode_fh() method. I did not gets ACKs from all filesystem maintainers, but the change is trivial and does not change any logic. Thanks, Amir. Changes since v1 [1]: - Patch #1 already merged into v6.6-rc7 - Fix build without CONFIG_EXPORTFS - Fix checkpatch warnings - Define symbolic constant for FILEID_INO64_GEN_LEN - Clarify documentation (units of) max_len argument [1] https://lore.kernel.org/r/20231018100000.2453965-1-amir73il@xxxxxxxxx/ [2] https://lore.kernel.org/r/20231023143049.2944970-1-amir73il@xxxxxxxxx/ Amir Goldstein (4): 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 | 54 +++++++++++++++------ 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 | 4 +- fs/ntfs/namei.c | 1 + fs/ntfs3/super.c | 1 + fs/overlayfs/util.c | 2 +- fs/smb/client/export.c | 11 ++--- fs/squashfs/export.c | 1 + fs/ufs/super.c | 1 + include/linux/exportfs.h | 51 ++++++++++++++++++- 24 files changed, 128 insertions(+), 40 deletions(-) -- 2.34.1
