/*
   * linux/fs/nfs/nfs4_fs.h
   *
   * Copyright (C) 2005 Trond Myklebust
   *
   * NFSv4-specific filesystem definitions and declarations
   */
  
  #ifndef __LINUX_FS_NFS_NFS4_FS_H
  #define __LINUX_FS_NFS_NFS4_FS_H
  
  #ifdef CONFIG_NFS_V4
  
  struct idmap;

  enum nfs4_client_state {

  	NFS4CLNT_MANAGER_RUNNING  = 0,

  	NFS4CLNT_CHECK_LEASE,

  	NFS4CLNT_LEASE_EXPIRED,

  	NFS4CLNT_RECLAIM_REBOOT,
  	NFS4CLNT_RECLAIM_NOGRACE,

  	NFS4CLNT_DELEGRETURN,

  	NFS4CLNT_LAYOUTRECALL,

  	NFS4CLNT_SESSION_RESET,

  	NFS4CLNT_RECALL_SLOT,

  	NFS4CLNT_LEASE_CONFIRM,

  	NFS4CLNT_SERVER_SCOPE_MISMATCH,

  };

  enum nfs4_session_state {

  	NFS4_SESSION_INITING,

  	NFS4_SESSION_DRAINING,
  };

  #define NFS4_RENEW_TIMEOUT		0x01
  #define NFS4_RENEW_DELEGATION_CB	0x02

  struct nfs4_minor_version_ops {
  	u32	minor_version;

  	int	(*call_sync)(struct rpc_clnt *clnt,
  			struct nfs_server *server,

  			struct rpc_message *msg,
  			struct nfs4_sequence_args *args,
  			struct nfs4_sequence_res *res,
  			int cache_reply);

  	int	(*validate_stateid)(struct nfs_delegation *,
  			const nfs4_stateid *);

  	int	(*find_root_sec)(struct nfs_server *, struct nfs_fh *,
  			struct nfs_fsinfo *);

  	const struct nfs4_state_recovery_ops *reboot_recovery_ops;
  	const struct nfs4_state_recovery_ops *nograce_recovery_ops;
  	const struct nfs4_state_maintenance_ops *state_renewal_ops;

  };

  /*

   * struct rpc_sequence ensures that RPC calls are sent in the exact
   * order that they appear on the list.
   */
  struct rpc_sequence {
  	struct rpc_wait_queue	wait;	/* RPC call delay queue */
  	spinlock_t lock;		/* Protects the list */
  	struct list_head list;		/* Defines sequence of RPC calls */
  };
  
  #define NFS_SEQID_CONFIRMED 1
  struct nfs_seqid_counter {
  	struct rpc_sequence *sequence;
  	int flags;
  	u32 counter;
  };
  
  struct nfs_seqid {

  	struct nfs_seqid_counter *sequence;

  	struct list_head list;

  };
  
  static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
  {
  	if (seqid_mutating_err(-status))
  		seqid->flags |= NFS_SEQID_CONFIRMED;
  }

  struct nfs_unique_id {
  	struct rb_node rb_node;
  	__u64 id;
  };

  /*

   * NFS4 state_owners and lock_owners are simply labels for ordered
   * sequences of RPC calls. Their sole purpose is to provide once-only
   * semantics by allowing the server to identify replayed requests.

   */
  struct nfs4_state_owner {

  	struct nfs_unique_id so_owner_id;

  	struct nfs_server    *so_server;

  	struct list_head     so_lru;
  	unsigned long        so_expires;

  	struct rb_node	     so_server_node;

  
  	struct rpc_cred	     *so_cred;	 /* Associated cred */

  
  	spinlock_t	     so_lock;
  	atomic_t	     so_count;

  	unsigned long	     so_flags;

  	struct list_head     so_states;

  	struct nfs_seqid_counter so_seqid;
  	struct rpc_sequence  so_sequence;

  };

  enum {
  	NFS_OWNER_RECLAIM_REBOOT,
  	NFS_OWNER_RECLAIM_NOGRACE
  };

  #define NFS_LOCK_NEW		0
  #define NFS_LOCK_RECLAIM	1
  #define NFS_LOCK_EXPIRED	2

  /*
   * struct nfs4_state maintains the client-side state for a given
   * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
   *
   * OPEN:
   * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
   * we need to know how many files are open for reading or writing on a
   * given inode. This information too is stored here.
   *
   * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
   */

  struct nfs4_lock_owner {
  	unsigned int lo_type;
  #define NFS4_ANY_LOCK_TYPE	(0U)
  #define NFS4_FLOCK_LOCK_TYPE	(1U << 0)
  #define NFS4_POSIX_LOCK_TYPE	(1U << 1)
  	union {
  		fl_owner_t posix_owner;
  		pid_t flock_owner;
  	} lo_u;
  };

  struct nfs4_lock_state {
  	struct list_head	ls_locks;	/* Other lock stateids */

  	struct nfs4_state *	ls_state;	/* Pointer to open state */

  #define NFS_LOCK_INITIALIZED 1
  	int			ls_flags;

  	struct nfs_seqid_counter	ls_seqid;

  	struct rpc_sequence	ls_sequence;

  	struct nfs_unique_id	ls_id;

  	nfs4_stateid		ls_stateid;
  	atomic_t		ls_count;

  	struct nfs4_lock_owner	ls_owner;

  };
  
  /* bits for nfs4_state->flags */
  enum {
  	LK_STATE_IN_USE,

  	NFS_DELEGATED_STATE,		/* Current stateid is delegation */
  	NFS_O_RDONLY_STATE,		/* OPEN stateid has read-only state */
  	NFS_O_WRONLY_STATE,		/* OPEN stateid has write-only state */
  	NFS_O_RDWR_STATE,		/* OPEN stateid has read/write state */

  	NFS_STATE_RECLAIM_REBOOT,	/* OPEN stateid server rebooted */
  	NFS_STATE_RECLAIM_NOGRACE,	/* OPEN stateid needs to recover state */

  	NFS_STATE_POSIX_LOCKS,		/* Posix locks are supported */

  };
  
  struct nfs4_state {
  	struct list_head open_states;	/* List of states for the same state_owner */
  	struct list_head inode_states;	/* List of states for the same inode */
  	struct list_head lock_states;	/* List of subservient lock stateids */
  
  	struct nfs4_state_owner *owner;	/* Pointer to the open owner */
  	struct inode *inode;		/* Pointer to the inode */
  
  	unsigned long flags;		/* Do we hold any locks? */

  	spinlock_t state_lock;		/* Protects the lock_states list */

  	seqlock_t seqlock;		/* Protects the stateid/open_stateid */

  	nfs4_stateid stateid;		/* Current stateid: may be delegation */
  	nfs4_stateid open_stateid;	/* OPEN stateid */

  	/* The following 3 fields are protected by owner->so_lock */

  	unsigned int n_rdonly;		/* Number of read-only references */
  	unsigned int n_wronly;		/* Number of write-only references */
  	unsigned int n_rdwr;		/* Number of read/write references */

  	fmode_t state;			/* State on the server (R,W, or RW) */

  	atomic_t count;
  };
  
  
  struct nfs4_exception {
  	long timeout;
  	int retry;

  	struct nfs4_state *state;

  };
  
  struct nfs4_state_recovery_ops {

  	int owner_flag_bit;

  	int state_flag_bit;

  	int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
  	int (*recover_lock)(struct nfs4_state *, struct file_lock *);

  	int (*establish_clid)(struct nfs_client *, struct rpc_cred *);

  	struct rpc_cred * (*get_clid_cred)(struct nfs_client *);

  	int (*reclaim_complete)(struct nfs_client *);

  };

  struct nfs4_state_maintenance_ops {

  	int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);

  	struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);

  	int (*renew_lease)(struct nfs_client *, struct rpc_cred *);

  };

  extern const struct dentry_operations nfs4_dentry_operations;

  extern const struct inode_operations nfs4_dir_inode_operations;

  /* nfs4proc.c */

  extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
  extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);

  extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);

  extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);

  extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);

  extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait, bool roc);

  extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);

  extern int nfs4_proc_fs_locations(struct inode *dir, const struct qstr *name,

  		struct nfs4_fs_locations *fs_locations, struct page *page);

  extern void nfs4_release_lockowner(const struct nfs4_lock_state *);

  extern const struct xattr_handler *nfs4_xattr_handlers[];

  #if defined(CONFIG_NFS_V4_1)

  static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
  {
  	return server->nfs_client->cl_session;
  }
  
  extern int nfs4_setup_sequence(const struct nfs_server *server,

  		struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
  		int cache_reply, struct rpc_task *task);

  extern int nfs41_setup_sequence(struct nfs4_session *session,
  		struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
  		int cache_reply, struct rpc_task *task);

  extern void nfs4_destroy_session(struct nfs4_session *session);
  extern struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp);

  extern int nfs4_proc_create_session(struct nfs_client *);

  extern int nfs4_proc_destroy_session(struct nfs4_session *);

  extern int nfs4_init_session(struct nfs_server *server);

  extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
  		struct nfs_fsinfo *fsinfo);

  extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,

  				  bool sync);

  
  static inline bool
  is_ds_only_client(struct nfs_client *clp)
  {
  	return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
  		EXCHGID4_FLAG_USE_PNFS_DS;
  }

  
  static inline bool
  is_ds_client(struct nfs_client *clp)
  {
  	return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
  }

  #else /* CONFIG_NFS_v4_1 */

  static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
  {
  	return NULL;
  }
  
  static inline int nfs4_setup_sequence(const struct nfs_server *server,

  		struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
  		int cache_reply, struct rpc_task *task)
  {
  	return 0;
  }

  
  static inline int nfs4_init_session(struct nfs_server *server)
  {
  	return 0;
  }

  
  static inline bool
  is_ds_only_client(struct nfs_client *clp)

  {
  	return false;
  }
  
  static inline bool
  is_ds_client(struct nfs_client *clp)

  {
  	return false;
  }

  #endif /* CONFIG_NFS_V4_1 */

  extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];

  extern const u32 nfs4_fattr_bitmap[2];
  extern const u32 nfs4_statfs_bitmap[2];
  extern const u32 nfs4_pathconf_bitmap[2];

  extern const u32 nfs4_fsinfo_bitmap[3];

  extern const u32 nfs4_fs_locations_bitmap[2];

  
  /* nfs4renewd.c */

  extern void nfs4_schedule_state_renewal(struct nfs_client *);

  extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);

  extern void nfs4_kill_renewd(struct nfs_client *);

  extern void nfs4_renew_state(struct work_struct *);

  
  /* nfs4state.c */

  struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp);

  struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);

  #if defined(CONFIG_NFS_V4_1)
  struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);

  struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp);

  extern void nfs4_schedule_session_recovery(struct nfs4_session *);
  #else
  static inline void nfs4_schedule_session_recovery(struct nfs4_session *session)
  {
  }

  #endif /* CONFIG_NFS_V4_1 */

  
  extern struct nfs4_state_owner * nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *);
  extern void nfs4_put_state_owner(struct nfs4_state_owner *);

  extern void nfs4_purge_state_owners(struct nfs_server *);

  extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
  extern void nfs4_put_open_state(struct nfs4_state *);

  extern void nfs4_close_state(struct nfs4_state *, fmode_t);
  extern void nfs4_close_sync(struct nfs4_state *, fmode_t);

  extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);

  extern void nfs4_schedule_lease_recovery(struct nfs_client *);

  extern void nfs4_schedule_state_manager(struct nfs_client *);

  extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);

  extern void nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);

  extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);

  extern void nfs41_handle_recall_slot(struct nfs_client *clp);

  extern void nfs41_handle_server_scope(struct nfs_client *,
  				      struct server_scope **);

  extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);

  extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);

  extern void nfs4_copy_stateid(nfs4_stateid *, struct nfs4_state *, fl_owner_t, pid_t);

  extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);

  extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
  extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
  extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);

  extern void nfs_release_seqid(struct nfs_seqid *seqid);

  extern void nfs_free_seqid(struct nfs_seqid *seqid);

  extern const nfs4_stateid zero_stateid;
  
  /* nfs4xdr.c */

  extern struct rpc_procinfo nfs4_procedures[];
  
  struct nfs4_mount_data;
  
  /* callback_xdr.c */
  extern struct svc_version nfs4_callback_version1;

  extern struct svc_version nfs4_callback_version4;

  
  #else

  #define nfs4_close_state(a, b) do { } while (0)
  #define nfs4_close_sync(a, b) do { } while (0)

  
  #endif /* CONFIG_NFS_V4 */
  #endif /* __LINUX_FS_NFS_NFS4_FS.H */