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authorLinus Torvalds <torvalds@linux-foundation.org>2023-11-07 12:11:26 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2023-11-07 12:11:26 -0800
commit13d88ac54ddd1011b6e94443958e798aa06eb835 (patch)
tree19167200e828ef0741b8df21a3b29795b93f2bdc /Documentation
parent062cca8915cad56aabb11206a4a5082856167fc0 (diff)
parent4ad714df58e646d4b2a454a7dface8ff903911c4 (diff)
Merge tag 'vfs-6.7.fsid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fanotify fsid updates from Christian Brauner: "This work is part of the plan to enable fanotify to serve as a drop-in replacement for inotify. While inotify is availabe on all filesystems, fanotify currently isn't. In order to support fanotify on all filesystems two things are needed: (1) all filesystems need to support AT_HANDLE_FID (2) all filesystems need to report a non-zero f_fsid This contains (1) and allows filesystems to encode non-decodable file handlers for fanotify without implementing any exportfs operations by encoding a file id of type FILEID_INO64_GEN from i_ino and i_generation. Filesystems that want to opt out of encoding non-decodable file ids for fanotify that don't support NFS export can do so by providing an empty export_operations struct. This also partially addresses (2) by generating f_fsid for simple filesystems as well as freevxfs. Remaining filesystems will be dealt with by separate patches. Finally, this contains the patch from the current exportfs maintainers which moves exportfs under vfs with Chuck, Jeff, and Amir as maintainers and vfs.git as tree" * tag 'vfs-6.7.fsid' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: MAINTAINERS: create an entry for exportfs fs: fix build error with CONFIG_EXPORTFS=m or not defined freevxfs: derive f_fsid from bdev->bd_dev fs: report f_fsid from s_dev for "simple" filesystems exportfs: support encoding non-decodeable file handles by default exportfs: define FILEID_INO64_GEN* file handle types exportfs: make ->encode_fh() a mandatory method for NFS export exportfs: add helpers to check if filesystem can encode/decode file handles
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/filesystems/nfs/exporting.rst7
-rw-r--r--Documentation/filesystems/porting.rst9
2 files changed, 11 insertions, 5 deletions
diff --git a/Documentation/filesystems/nfs/exporting.rst b/Documentation/filesystems/nfs/exporting.rst
index 198d805d611c..f04ce1215a03 100644
--- a/Documentation/filesystems/nfs/exporting.rst
+++ b/Documentation/filesystems/nfs/exporting.rst
@@ -122,12 +122,9 @@ are exportable by setting the s_export_op field in the struct
super_block. This field must point to a "struct export_operations"
struct which has the following members:
- encode_fh (optional)
+ encode_fh (mandatory)
Takes a dentry and creates a filehandle fragment which may later be used
- to find or create a dentry for the same object. The default
- implementation creates a filehandle fragment that encodes a 32bit inode
- and generation number for the inode encoded, and if necessary the
- same information for the parent.
+ to find or create a dentry for the same object.
fh_to_dentry (mandatory)
Given a filehandle fragment, this should find the implied object and
diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst
index d69f59700a23..878e72b2f8b7 100644
--- a/Documentation/filesystems/porting.rst
+++ b/Documentation/filesystems/porting.rst
@@ -1052,3 +1052,12 @@ kill_anon_super(), or kill_block_super() helpers.
Lock ordering has been changed so that s_umount ranks above open_mutex again.
All places where s_umount was taken under open_mutex have been fixed up.
+
+---
+
+**mandatory**
+
+export_operations ->encode_fh() no longer has a default implementation to
+encode FILEID_INO32_GEN* file handles.
+Filesystems that used the default implementation may use the generic helper
+generic_encode_ino32_fh() explicitly.