afs: Implement sillyrename for unlink and rename

Implement sillyrename for AFS unlink and rename, using the NFS variant
implementation as a basis.

Note that the asynchronous file locking extender/releaser has to be
notified with a state change to stop it complaining if there's a race
between that and the actual file deletion.

A tracepoint, afs_silly_rename, is also added to note the silly rename and
the cleanup.  The afs_edit_dir tracepoint is given some extra reason
indicators and the afs_flock_ev tracepoint is given a silly-delete file
lock cancellation indicator.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/afs/super.c b/fs/afs/super.c
index 5adf012b8e27..6438849a75c4 100644
--- a/fs/afs/super.c
+++ b/fs/afs/super.c
@@ -45,7 +45,7 @@ struct file_system_type afs_fs_type = {
         .init_fs_context        = afs_init_fs_context,
         .parameters             = &afs_fs_parameters,
         .kill_sb                = afs_kill_super,
-        .fs_flags               = 0,
+        .fs_flags               = FS_RENAME_DOES_D_MOVE,
 };
 MODULE_ALIAS_FS("afs");
 
@@ -656,6 +656,8 @@ static struct inode *afs_alloc_inode(struct super_block *sb)
         vnode->cb_type          = 0;
         vnode->lock_state       = AFS_VNODE_LOCK_NONE;
 
+        init_rwsem(&vnode->rmdir_lock);
+
         _leave(" = %p", &vnode->vfs_inode);
         return &vnode->vfs_inode;
 }