Jan, Following up on the FAN_REPORT_ANY_FID proposal [1], here is a shot at an alternative proposal to seamlessly support more filesystems. While fanotify relaxes the requirements for filesystems to support reporting fid to require only the ->encode_fh() operation, there are currently no new filesystems that meet the relaxed requirements. I will shortly post patches that allow overlayfs to meet the new requirements with default overlay configurations. The overlay and vfs/fanotify patch sets are completely independent. The are both available on my github branch [2] and there is a simple LTP test variant that tests reporting fid from overlayfs [3], which also demonstrates the minor UAPI change of name_to_handle_at(2) for requesting a non-decodeable file handle by userspace. Thanks, Amir. [1] https://lore.kernel.org/linux-fsdevel/20230417162721.ouzs33oh6mb7vtft@quack3/ [2] https://github.com/amir73il/linux/commits/exportfs_encode_fid [3] https://github.com/amir73il/ltp/commits/exportfs_encode_fid Amir Goldstein (4): exportfs: change connectable argument to bit flags exportfs: add explicit flag to request non-decodeable file handles exportfs: allow exporting non-decodeable file handles to userspace fanotify: support reporting non-decodeable file handles Documentation/filesystems/nfs/exporting.rst | 4 +-- fs/exportfs/expfs.c | 29 ++++++++++++++++++--- fs/fhandle.c | 20 ++++++++------ fs/nfsd/nfsfh.c | 5 ++-- fs/notify/fanotify/fanotify.c | 4 +-- fs/notify/fanotify/fanotify_user.c | 6 ++--- fs/notify/fdinfo.c | 2 +- include/linux/exportfs.h | 18 ++++++++++--- include/uapi/linux/fcntl.h | 5 ++++ 9 files changed, 67 insertions(+), 26 deletions(-) -- 2.34.1
