diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2026-01-29 11:02:11 +0100 |
|---|---|---|
| committer | Christian Brauner <brauner@kernel.org> | 2026-01-29 17:26:30 +0100 |
| commit | a39162f77f49b618df5a721a1e48d8b903280fbd (patch) | |
| tree | 52f3441c7b17037f10beafa06e844953d3bc8775 /include/linux | |
| parent | b1353865ce0fda5e8117ea3951869d24bbbc74f3 (diff) | |
exportfs: clarify the documentation of open()/permission() expotrfs ops
pidfs and nsfs recently gained support for encode/decode of file handles
via name_to_handle_at(2)/open_by_handle_at(2).
These special kernel filesystems have custom ->open() and ->permission()
export methods, which nfsd does not respect and it was never meant to be
used for exporting those filesystems by nfsd.
Update kernel-doc comments to express the fact the those methods are for
open_by_handle(2) system only and not compatible with nfsd.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://patch.msgid.link/20260129100212.49727-2-amir73il@gmail.com
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/exportfs.h | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h index 262e24d83313..0660953c3fb7 100644 --- a/include/linux/exportfs.h +++ b/include/linux/exportfs.h @@ -200,6 +200,10 @@ struct handle_to_path_ctx { * @get_parent: find the parent of a given directory * @commit_metadata: commit metadata changes to stable storage * + * Methods for open_by_handle(2) syscall with special kernel file systems: + * @permission: custom permission for opening a file by handle + * @open: custom open routine for opening file by handle + * * See Documentation/filesystems/nfs/exporting.rst for details on how to use * this interface correctly and the definition of the flags. * @@ -244,10 +248,14 @@ struct handle_to_path_ctx { * space cannot be allocated, a %ERR_PTR should be returned. * * @permission: - * Allow filesystems to specify a custom permission function. + * Allow filesystems to specify a custom permission function for the + * open_by_handle_at(2) syscall instead of the default permission check. + * This custom permission function is not respected by nfsd. * * @open: - * Allow filesystems to specify a custom open function. + * Allow filesystems to specify a custom open function for the + * open_by_handle_at(2) syscall instead of the default file_open_root(). + * This custom open function is not respected by nfsd. * * @commit_metadata: * @commit_metadata should commit metadata changes to stable storage. |