On Sat, Apr 29, 2023 at 8:26 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > On Sat, Apr 29, 2023 at 5:45 PM Chuck Lever <cel@xxxxxxxxxx> wrote: > > > > On Thu, Apr 27, 2023 at 11:13:33AM -0400, Jeff Layton wrote: > > > On Tue, 2023-04-25 at 16:01 +0300, Amir Goldstein wrote: > > > > 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(-) > > > > > > > > > > This set looks fairly benign to me, so ACK on the general concept. > > > > Me also (modulo previous review comments), so > > > > Acked-by: Chuck Lever <chuck.lever@xxxxxxxxxx> > > > > I assume either Amir or Jeff will take these when they are ready. > > If I'm wrong, please do let me know and I can take them via the > > NFSD tree. > > > > With your and Jeff's ACKs I think it would be best if Jan takes > these changes through the fsnotify tree, because they are only > meant to improve fanotify at this point. > > > > > > I am starting to dislike how the AT_* flags are turning into a bunch of > > > flags that only have meanings on certain syscalls. I don't see a cleaner > > > way to handle it though. > > With all the various proposals of file_handle_v2, I still think that the > AT_HANDLE_FID is the cleanest in terms of API simplicity. > > Just trying to document file_handle_v2 and backward compat with > file_handle_v1 gives me a headache and documenting AT_HANDLE_FID > is a no brainer. > To prove my point, here is the man page draft for AT_HANDLE_FID: https://github.com/amir73il/man-pages/commit/da7e8dc4749ced85ba692073a42724f2bbe5fe3b Thanks, Amir.