[PATCH] 2.4.19-rc1/2.5.25 provide dummy fsync() routine for directories on NFS mounts

[Trond Myklebust]

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Hi,

   There was a bug reported on the 'exim' user list a couple of months ago: 
the Linux NFS client reports -EINVAL if you try to fsync() a directory.

   The correct response would be to return a dummy '0' for success, since all 
NFS operations that change the directory are supposed to be performed 
synchronously on the server anyway...

Cheers,
  Trond

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diff -u --recursive --new-file linux-2.4.19-rc1/fs/nfs/dir.c linux-2.4.19-fsync_dir/fs/nfs/dir.c
--- linux-2.4.19-rc1/fs/nfs/dir.c	Tue Mar 12 16:35:02 2002
+++ linux-2.4.19-fsync_dir/fs/nfs/dir.c	Tue Jul  9 15:41:29 2002
@@ -45,12 +45,14 @@
 static int nfs_mknod(struct inode *, struct dentry *, int, int);
 static int nfs_rename(struct inode *, struct dentry *,
 		      struct inode *, struct dentry *);
+static int nfs_fsync_dir(struct file *, struct dentry *, int);
 
 struct file_operations nfs_dir_operations = {
 	read:		generic_read_dir,
 	readdir:	nfs_readdir,
 	open:		nfs_open,
 	release:	nfs_release,
+	fsync:		nfs_fsync_dir
 };
 
 struct inode_operations nfs_dir_inode_operations = {
@@ -401,6 +403,15 @@
 	return 0;
 }
 
+/*
+ * All directory operations under NFS are synchronous, so fsync()
+ * is a dummy operation.
+ */
+int nfs_fsync_dir(struct file *filp, struct dentry *dentry, int datasync)
+{
+	return 0;
+}
+
 /*
  * A check for whether or not the parent directory has changed.
  * In the case it has, we assume that the dentries are untrustworthy

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