/*
   * linux/fs/lockd/svc4proc.c
   *
   * Lockd server procedures. We don't implement the NLM_*_RES 
   * procedures because we don't use the async procedures.
   *
   * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   */
  
  #include <linux/types.h>
  #include <linux/time.h>
  #include <linux/lockd/lockd.h>
  #include <linux/lockd/share.h>
  #include <linux/sunrpc/svc_xprt.h>
  
  #define NLMDBG_FACILITY		NLMDBG_CLIENT
  
  /*
   * Obtain client and file from arguments
   */
  static __be32
  nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
  			struct nlm_host **hostp, struct nlm_file **filp)
  {
  	struct nlm_host		*host = NULL;
  	struct nlm_file		*file = NULL;
  	struct nlm_lock		*lock = &argp->lock;
  	__be32			error = 0;
  
  	/* nfsd callbacks must have been installed for this procedure */
  	if (!nlmsvc_ops)
  		return nlm_lck_denied_nolocks;
  
  	/* Obtain host handle */
  	if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
  	 || (argp->monitor && nsm_monitor(host) < 0))
  		goto no_locks;
  	*hostp = host;
  
  	/* Obtain file pointer. Not used by FREE_ALL call. */
  	if (filp != NULL) {
  		if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
  			goto no_locks;
  		*filp = file;
  
  		/* Set up the missing parts of the file_lock structure */
  		lock->fl.fl_file  = file->f_file;
  		lock->fl.fl_owner = (fl_owner_t) host;
  		lock->fl.fl_lmops = &nlmsvc_lock_operations;
  	}
  
  	return 0;
  
  no_locks:
  	nlmsvc_release_host(host);
   	if (error)
  		return error;	
  	return nlm_lck_denied_nolocks;
  }
  
  /*
   * NULL: Test for presence of service
   */
  static __be32
  nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
  {
  	dprintk("lockd: NULL          called
  ");
  	return rpc_success;
  }
  
  /*
   * TEST: Check for conflicting lock
   */
  static __be32
  nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
  				         struct nlm_res  *resp)
  {
  	struct nlm_host	*host;
  	struct nlm_file	*file;
  	__be32 rc = rpc_success;
  
  	dprintk("lockd: TEST4        called
  ");
  	resp->cookie = argp->cookie;
  
  	/* Obtain client and file */
  	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  
  	/* Now check for conflicting locks */
  	resp->status = nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie);
  	if (resp->status == nlm_drop_reply)
  		rc = rpc_drop_reply;
  	else
  		dprintk("lockd: TEST4        status %d
  ", ntohl(resp->status));
  
  	nlmsvc_release_host(host);
  	nlm_release_file(file);
  	return rc;
  }
  
  static __be32
  nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
  				         struct nlm_res  *resp)
  {
  	struct nlm_host	*host;
  	struct nlm_file	*file;
  	__be32 rc = rpc_success;
  
  	dprintk("lockd: LOCK          called
  ");
  
  	resp->cookie = argp->cookie;
  
  	/* Obtain client and file */
  	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  
  #if 0
  	/* If supplied state doesn't match current state, we assume it's
  	 * an old request that time-warped somehow. Any error return would
  	 * do in this case because it's irrelevant anyway.
  	 *
  	 * NB: We don't retrieve the remote host's state yet.
  	 */
  	if (host->h_nsmstate && host->h_nsmstate != argp->state) {
  		resp->status = nlm_lck_denied_nolocks;
  	} else
  #endif
  
  	/* Now try to lock the file */
  	resp->status = nlmsvc_lock(rqstp, file, host, &argp->lock,
  					argp->block, &argp->cookie,
  					argp->reclaim);
  	if (resp->status == nlm_drop_reply)
  		rc = rpc_drop_reply;
  	else
  		dprintk("lockd: LOCK         status %d
  ", ntohl(resp->status));
  
  	nlmsvc_release_host(host);
  	nlm_release_file(file);
  	return rc;
  }
  
  static __be32
  nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
  				           struct nlm_res  *resp)
  {
  	struct nlm_host	*host;
  	struct nlm_file	*file;
  
  	dprintk("lockd: CANCEL        called
  ");
  
  	resp->cookie = argp->cookie;
  
  	/* Don't accept requests during grace period */
  	if (locks_in_grace(SVC_NET(rqstp))) {
  		resp->status = nlm_lck_denied_grace_period;
  		return rpc_success;
  	}
  
  	/* Obtain client and file */
  	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  
  	/* Try to cancel request. */
  	resp->status = nlmsvc_cancel_blocked(SVC_NET(rqstp), file, &argp->lock);
  
  	dprintk("lockd: CANCEL        status %d
  ", ntohl(resp->status));
  	nlmsvc_release_host(host);
  	nlm_release_file(file);
  	return rpc_success;
  }
  
  /*
   * UNLOCK: release a lock
   */
  static __be32
  nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
  				           struct nlm_res  *resp)
  {
  	struct nlm_host	*host;
  	struct nlm_file	*file;
  
  	dprintk("lockd: UNLOCK        called
  ");
  
  	resp->cookie = argp->cookie;
  
  	/* Don't accept new lock requests during grace period */
  	if (locks_in_grace(SVC_NET(rqstp))) {
  		resp->status = nlm_lck_denied_grace_period;
  		return rpc_success;
  	}
  
  	/* Obtain client and file */
  	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  
  	/* Now try to remove the lock */
  	resp->status = nlmsvc_unlock(SVC_NET(rqstp), file, &argp->lock);
  
  	dprintk("lockd: UNLOCK        status %d
  ", ntohl(resp->status));
  	nlmsvc_release_host(host);
  	nlm_release_file(file);
  	return rpc_success;
  }
  
  /*
   * GRANTED: A server calls us to tell that a process' lock request
   * was granted
   */
  static __be32
  nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
  				            struct nlm_res  *resp)
  {
  	resp->cookie = argp->cookie;
  
  	dprintk("lockd: GRANTED       called
  ");
  	resp->status = nlmclnt_grant(svc_addr(rqstp), &argp->lock);
  	dprintk("lockd: GRANTED       status %d
  ", ntohl(resp->status));
  	return rpc_success;
  }
  
  /*
   * This is the generic lockd callback for async RPC calls
   */
  static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
  {
  	dprintk("lockd: %5u callback returned %d
  ", task->tk_pid,
  			-task->tk_status);
  }
  
  static void nlm4svc_callback_release(void *data)
  {
  	nlmsvc_release_call(data);
  }
  
  static const struct rpc_call_ops nlm4svc_callback_ops = {
  	.rpc_call_done = nlm4svc_callback_exit,
  	.rpc_release = nlm4svc_callback_release,
  };
  
  /*
   * `Async' versions of the above service routines. They aren't really,
   * because we send the callback before the reply proper. I hope this
   * doesn't break any clients.
   */
  static __be32 nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
  		__be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res  *))
  {
  	struct nlm_host	*host;
  	struct nlm_rqst	*call;
  	__be32 stat;
  
  	host = nlmsvc_lookup_host(rqstp,
  				  argp->lock.caller,
  				  argp->lock.len);
  	if (host == NULL)
  		return rpc_system_err;
  
  	call = nlm_alloc_call(host);
  	nlmsvc_release_host(host);
  	if (call == NULL)
  		return rpc_system_err;
  
  	stat = func(rqstp, argp, &call->a_res);
  	if (stat != 0) {
  		nlmsvc_release_call(call);
  		return stat;
  	}
  
  	call->a_flags = RPC_TASK_ASYNC;
  	if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
  		return rpc_system_err;
  	return rpc_success;
  }
  
  static __be32 nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
  					     void	     *resp)
  {
  	dprintk("lockd: TEST_MSG      called
  ");
  	return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
  }
  
  static __be32 nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
  					     void	     *resp)
  {
  	dprintk("lockd: LOCK_MSG      called
  ");
  	return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
  }
  
  static __be32 nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
  					       void	       *resp)
  {
  	dprintk("lockd: CANCEL_MSG    called
  ");
  	return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
  }
  
  static __be32 nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
                                                 void            *resp)
  {
  	dprintk("lockd: UNLOCK_MSG    called
  ");
  	return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
  }
  
  static __be32 nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
                                                  void            *resp)
  {
  	dprintk("lockd: GRANTED_MSG   called
  ");
  	return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
  }
  
  /*
   * SHARE: create a DOS share or alter existing share.
   */
  static __be32
  nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
  				          struct nlm_res  *resp)
  {
  	struct nlm_host	*host;
  	struct nlm_file	*file;
  
  	dprintk("lockd: SHARE         called
  ");
  
  	resp->cookie = argp->cookie;
  
  	/* Don't accept new lock requests during grace period */
  	if (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
  		resp->status = nlm_lck_denied_grace_period;
  		return rpc_success;
  	}
  
  	/* Obtain client and file */
  	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  
  	/* Now try to create the share */
  	resp->status = nlmsvc_share_file(host, file, argp);
  
  	dprintk("lockd: SHARE         status %d
  ", ntohl(resp->status));
  	nlmsvc_release_host(host);
  	nlm_release_file(file);
  	return rpc_success;
  }
  
  /*
   * UNSHARE: Release a DOS share.
   */
  static __be32
  nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
  				            struct nlm_res  *resp)
  {
  	struct nlm_host	*host;
  	struct nlm_file	*file;
  
  	dprintk("lockd: UNSHARE       called
  ");
  
  	resp->cookie = argp->cookie;
  
  	/* Don't accept requests during grace period */
  	if (locks_in_grace(SVC_NET(rqstp))) {
  		resp->status = nlm_lck_denied_grace_period;
  		return rpc_success;
  	}
  
  	/* Obtain client and file */
  	if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
  		return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
  
  	/* Now try to lock the file */
  	resp->status = nlmsvc_unshare_file(host, file, argp);
  
  	dprintk("lockd: UNSHARE       status %d
  ", ntohl(resp->status));
  	nlmsvc_release_host(host);
  	nlm_release_file(file);
  	return rpc_success;
  }
  
  /*
   * NM_LOCK: Create an unmonitored lock
   */
  static __be32
  nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
  				            struct nlm_res  *resp)
  {
  	dprintk("lockd: NM_LOCK       called
  ");
  
  	argp->monitor = 0;		/* just clean the monitor flag */
  	return nlm4svc_proc_lock(rqstp, argp, resp);
  }
  
  /*
   * FREE_ALL: Release all locks and shares held by client
   */
  static __be32
  nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
  					     void            *resp)
  {
  	struct nlm_host	*host;
  
  	/* Obtain client */
  	if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
  		return rpc_success;
  
  	nlmsvc_free_host_resources(host);
  	nlmsvc_release_host(host);
  	return rpc_success;
  }
  
  /*
   * SM_NOTIFY: private callback from statd (not part of official NLM proto)
   */
  static __be32
  nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
  					      void	        *resp)
  {
  	dprintk("lockd: SM_NOTIFY     called
  ");
  
  	if (!nlm_privileged_requester(rqstp)) {
  		char buf[RPC_MAX_ADDRBUFLEN];
  		printk(KERN_WARNING "lockd: rejected NSM callback from %s
  ",
  				svc_print_addr(rqstp, buf, sizeof(buf)));
  		return rpc_system_err;
  	}
  
  	nlm_host_rebooted(argp);
  	return rpc_success;
  }
  
  /*
   * client sent a GRANTED_RES, let's remove the associated block
   */
  static __be32
  nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res  *argp,
                                                  void            *resp)
  {
          if (!nlmsvc_ops)
                  return rpc_success;
  
          dprintk("lockd: GRANTED_RES   called
  ");
  
          nlmsvc_grant_reply(&argp->cookie, argp->status);
          return rpc_success;
  }
  
  
  /*
   * NLM Server procedures.
   */
  
  #define nlm4svc_encode_norep	nlm4svc_encode_void
  #define nlm4svc_decode_norep	nlm4svc_decode_void
  #define nlm4svc_decode_testres	nlm4svc_decode_void
  #define nlm4svc_decode_lockres	nlm4svc_decode_void
  #define nlm4svc_decode_unlockres	nlm4svc_decode_void
  #define nlm4svc_decode_cancelres	nlm4svc_decode_void
  #define nlm4svc_decode_grantedres	nlm4svc_decode_void
  
  #define nlm4svc_proc_none	nlm4svc_proc_null
  #define nlm4svc_proc_test_res	nlm4svc_proc_null
  #define nlm4svc_proc_lock_res	nlm4svc_proc_null
  #define nlm4svc_proc_cancel_res	nlm4svc_proc_null
  #define nlm4svc_proc_unlock_res	nlm4svc_proc_null
  
  struct nlm_void			{ int dummy; };
  
  #define PROC(name, xargt, xrest, argt, rest, respsize)	\
   { .pc_func	= (svc_procfunc) nlm4svc_proc_##name,	\
     .pc_decode	= (kxdrproc_t) nlm4svc_decode_##xargt,	\
     .pc_encode	= (kxdrproc_t) nlm4svc_encode_##xrest,	\
     .pc_release	= NULL,					\
     .pc_argsize	= sizeof(struct nlm_##argt),		\
     .pc_ressize	= sizeof(struct nlm_##rest),		\
     .pc_xdrressize = respsize,				\
   }
  #define	Ck	(1+XDR_QUADLEN(NLM_MAXCOOKIELEN))	/* cookie */
  #define	No	(1+1024/4)				/* netobj */
  #define	St	1					/* status */
  #define	Rg	4					/* range (offset + length) */
  struct svc_procedure		nlmsvc_procedures4[] = {
    PROC(null,		void,		void,		void,	void, 1),
    PROC(test,		testargs,	testres,	args,	res, Ck+St+2+No+Rg),
    PROC(lock,		lockargs,	res,		args,	res, Ck+St),
    PROC(cancel,		cancargs,	res,		args,	res, Ck+St),
    PROC(unlock,		unlockargs,	res,		args,	res, Ck+St),
    PROC(granted,		testargs,	res,		args,	res, Ck+St),
    PROC(test_msg,	testargs,	norep,		args,	void, 1),
    PROC(lock_msg,	lockargs,	norep,		args,	void, 1),
    PROC(cancel_msg,	cancargs,	norep,		args,	void, 1),
    PROC(unlock_msg,	unlockargs,	norep,		args,	void, 1),
    PROC(granted_msg,	testargs,	norep,		args,	void, 1),
    PROC(test_res,	testres,	norep,		res,	void, 1),
    PROC(lock_res,	lockres,	norep,		res,	void, 1),
    PROC(cancel_res,	cancelres,	norep,		res,	void, 1),
    PROC(unlock_res,	unlockres,	norep,		res,	void, 1),
    PROC(granted_res,	res,		norep,		res,	void, 1),
    /* statd callback */
    PROC(sm_notify,	reboot,		void,		reboot,	void, 1),
    PROC(none,		void,		void,		void,	void, 0),
    PROC(none,		void,		void,		void,	void, 0),
    PROC(none,		void,		void,		void,	void, 0),
    PROC(share,		shareargs,	shareres,	args,	res, Ck+St+1),
    PROC(unshare,		shareargs,	shareres,	args,	res, Ck+St+1),
    PROC(nm_lock,		lockargs,	res,		args,	res, Ck+St),
    PROC(free_all,	notify,		void,		args,	void, 1),
  
  };