summaryrefslogtreecommitdiff
path: root/Documentation/filesystems/nfs/exporting.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/filesystems/nfs/exporting.rst')
-rw-r--r--Documentation/filesystems/nfs/exporting.rst14
1 files changed, 9 insertions, 5 deletions
diff --git a/Documentation/filesystems/nfs/exporting.rst b/Documentation/filesystems/nfs/exporting.rst
index 4b30daee399a..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
@@ -241,3 +238,10 @@ following flags are defined:
all of an inode's dirty data on last close. Exports that behave this
way should set EXPORT_OP_FLUSH_ON_CLOSE so that NFSD knows to skip
waiting for writeback when closing such files.
+
+ EXPORT_OP_ASYNC_LOCK - Indicates a capable filesystem to do async lock
+ requests from lockd. Only set EXPORT_OP_ASYNC_LOCK if the filesystem has
+ it's own ->lock() functionality as core posix_lock_file() implementation
+ has no async lock request handling yet. For more information about how to
+ indicate an async lock request from a ->lock() file_operations struct, see
+ fs/locks.c and comment for the function vfs_lock_file().