fs/nfs/nfs4_fs.h - kernel/msm-4.19 - Gitiles

 /*
  * 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

 #if IS_ENABLED(CONFIG_NFS_V4)

 #define NFS4_MAX_LOOP_ON_RECOVER (10)

 #include <linux/seqlock.h>

 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_SESSION_RESET,
 	NFS4CLNT_LEASE_CONFIRM,
 	NFS4CLNT_SERVER_SCOPE_MISMATCH,
 	NFS4CLNT_PURGE_STATE,
 	NFS4CLNT_BIND_CONN_TO_SESSION,
 };

 #define NFS4_RENEW_TIMEOUT		0x01
 #define NFS4_RENEW_DELEGATION_CB	0x02

 struct nfs4_minor_version_ops {
 	u32	minor_version;
 	unsigned init_caps;

 	int	(*init_client)(struct nfs_client *);
 	void	(*shutdown_client)(struct nfs_client *);
 	bool	(*match_stateid)(const nfs4_stateid *,
 			const nfs4_stateid *);
 	int	(*find_root_sec)(struct nfs_server *, struct nfs_fh *,
 			struct nfs_fsinfo *);
 	int	(*free_lock_state)(struct nfs_server *,
 			struct nfs4_lock_state *);
 	const struct rpc_call_ops *call_sync_ops;
 	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;
 };

 #define NFS_SEQID_CONFIRMED 1
 struct nfs_seqid_counter {
 	ktime_t create_time;
 	int owner_id;
 	int flags;
 	u32 counter;
 	spinlock_t lock;		/* Protects the list */
 	struct list_head list;		/* Defines sequence of RPC calls */
 	struct rpc_wait_queue	wait;	/* RPC call delay queue */
 };

 struct nfs_seqid {
 	struct nfs_seqid_counter *sequence;
 	struct list_head list;
 	struct rpc_task *task;
 };

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

 /*
  * 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_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;
 	seqcount_t	     so_reclaim_seqcount;
 	struct mutex	     so_delegreturn_mutex;
 };

 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 0
 #define NFS_LOCK_LOST        1
 	unsigned long		ls_flags;
 	struct nfs_seqid_counter	ls_seqid;
 	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_OPEN_STATE,			/* OPEN stateid is set */
 	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 */
 	NFS_STATE_RECOVERY_FAILED,	/* OPEN stateid state recovery failed */
 };

 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 inode *inode;
 };

 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 *);
 	int (*reclaim_complete)(struct nfs_client *, struct rpc_cred *);
 	int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
 		struct rpc_cred *);
 };

 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;

 /* dir.c */
 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
 		    unsigned, umode_t, int *);

 /* super.c */
 extern struct file_system_type nfs4_fs_type;

 /* nfs4namespace.c */
 rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *);
 struct rpc_clnt *nfs4_create_sec_client(struct rpc_clnt *, struct inode *, struct qstr *);
 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
 			       struct nfs_fh *, struct nfs_fattr *);
 int nfs4_replace_transport(struct nfs_server *server,
 				const struct nfs4_fs_locations *locations);

 /* 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_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
 extern int nfs4_destroy_clientid(struct nfs_client *clp);
 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);
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
 				  struct nfs4_fs_locations *, struct page *);
 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, struct qstr *,
 			    struct nfs_fh *, struct nfs_fattr *);
 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
 extern const struct xattr_handler *nfs4_xattr_handlers[];
 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
 		const struct nfs_open_context *ctx,
 		const struct nfs_lock_context *l_ctx,
 		fmode_t fmode);

 #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 nfs41_setup_sequence(struct nfs4_session *session,
 		struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
 		struct rpc_task *task);
 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
 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;
 }

 static inline bool
 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 		    struct rpc_clnt **clntp, struct rpc_message *msg)
 {
 	struct rpc_cred *newcred = NULL;
 	rpc_authflavor_t flavor;

 	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
 		spin_lock(&clp->cl_lock);
 		if (clp->cl_machine_cred != NULL)
 			/* don't call get_rpccred on the machine cred -
 			 * a reference will be held for life of clp */
 			newcred = clp->cl_machine_cred;
 		spin_unlock(&clp->cl_lock);
 		msg->rpc_cred = newcred;

 		flavor = clp->cl_rpcclient->cl_auth->au_flavor;
 		WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
 			     flavor != RPC_AUTH_GSS_KRB5P);
 		*clntp = clp->cl_rpcclient;

 		return true;
 	}
 	return false;
 }

 /*
  * Function responsible for determining if an rpc_message should use the
  * machine cred under SP4_MACH_CRED and if so switching the credential and
  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
  * Should be called before rpc_call_sync/rpc_call_async.
  */
 static inline void
 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
 		   struct rpc_clnt **clntp, struct rpc_message *msg)
 {
 	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
 }

 /*
  * Special wrapper to nfs4_state_protect for write.
  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
  * that use machine cred use NFS_FILE_SYNC.
  */
 static inline void
 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 			 struct rpc_message *msg, struct nfs_write_data *wdata)
 {
 	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
 	    !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
 		wdata->args.stable = NFS_FILE_SYNC;
 }
 #else /* CONFIG_NFS_v4_1 */
 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
 {
 	return NULL;
 }

 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;
 }

 static inline void
 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
 		   struct rpc_clnt **clntp, struct rpc_message *msg)
 {
 }

 static inline void
 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
 			 struct rpc_message *msg, struct nfs_write_data *wdata)
 {
 }
 #endif /* CONFIG_NFS_V4_1 */

 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];

 extern const u32 nfs4_fattr_bitmap[3];
 extern const u32 nfs4_statfs_bitmap[3];
 extern const u32 nfs4_pathconf_bitmap[3];
 extern const u32 nfs4_fsinfo_bitmap[3];
 extern const u32 nfs4_fs_locations_bitmap[3];

 void nfs40_shutdown_client(struct nfs_client *);
 void nfs41_shutdown_client(struct nfs_client *);
 int nfs40_init_client(struct nfs_client *);
 int nfs41_init_client(struct nfs_client *);
 void nfs4_free_client(struct nfs_client *);

 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);

 /* 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_clid_cred(struct nfs_client *clp);
 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
 int nfs4_discover_server_trunking(struct nfs_client *clp,
 			struct nfs_client **);
 int nfs40_discover_server_trunking(struct nfs_client *clp,
 			struct nfs_client **, struct rpc_cred *);
 #if defined(CONFIG_NFS_V4_1)
 int nfs41_discover_server_trunking(struct nfs_client *clp,
 			struct nfs_client **, struct rpc_cred *);
 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
 extern void nfs41_server_notify_target_slotid_update(struct nfs_client *clp);
 extern void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp);

 #else
 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
 {
 }
 #endif /* CONFIG_NFS_V4_1 */

 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
 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 nfs_inode_find_state_and_recover(struct inode *inode,
 		const nfs4_stateid *stateid);
 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
 extern void nfs4_schedule_state_manager(struct nfs_client *);
 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 extern int 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_server_scope(struct nfs_client *,
 				      struct nfs41_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 int nfs4_select_rw_stateid(nfs4_stateid *, struct nfs4_state *,
 		fmode_t, const struct nfs_lockowner *);

 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 void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);

 extern const nfs4_stateid zero_stateid;

 /* nfs4super.c */
 struct nfs_mount_info;
 extern struct nfs_subversion nfs_v4;
 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
 extern bool nfs4_disable_idmapping;
 extern unsigned short max_session_slots;
 extern unsigned short send_implementation_id;
 extern bool recover_lost_locks;

 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];

 /* nfs4sysctl.c */
 #ifdef CONFIG_SYSCTL
 int nfs4_register_sysctl(void);
 void nfs4_unregister_sysctl(void);
 #else
 static inline int nfs4_register_sysctl(void)
 {
 	return 0;
 }

 static inline void nfs4_unregister_sysctl(void)
 {
 }
 #endif

 /* 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;

 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
 {
 	memcpy(dst, src, sizeof(*dst));
 }

 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
 {
 	return memcmp(dst, src, sizeof(*dst)) == 0;
 }

 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
 {
 	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
 }

 #else

 #define nfs4_close_state(a, b) do { } while (0)
 #define nfs4_close_sync(a, b) do { } while (0)
 #define nfs4_state_protect(a, b, c, d) do { } while (0)
 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)

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

	#if IS_ENABLED(CONFIG_NFS_V4)

	#define NFS4_MAX_LOOP_ON_RECOVER (10)

	#include <linux/seqlock.h>

	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_SESSION_RESET,
	NFS4CLNT_LEASE_CONFIRM,
	NFS4CLNT_SERVER_SCOPE_MISMATCH,
	NFS4CLNT_PURGE_STATE,
	NFS4CLNT_BIND_CONN_TO_SESSION,
	};

	#define NFS4_RENEW_TIMEOUT 0x01
	#define NFS4_RENEW_DELEGATION_CB 0x02

	struct nfs4_minor_version_ops {
	u32 minor_version;
	unsigned init_caps;

	int (init_client)(struct nfs_client );
	void (shutdown_client)(struct nfs_client );
	bool (match_stateid)(const nfs4_stateid ,
	const nfs4_stateid *);
	int (find_root_sec)(struct nfs_server , struct nfs_fh *,
	struct nfs_fsinfo *);
	int (free_lock_state)(struct nfs_server ,
	struct nfs4_lock_state *);
	const struct rpc_call_ops *call_sync_ops;
	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;
	};

	#define NFS_SEQID_CONFIRMED 1
	struct nfs_seqid_counter {
	ktime_t create_time;
	int owner_id;
	int flags;
	u32 counter;
	spinlock_t lock; /* Protects the list */
	struct list_head list; /* Defines sequence of RPC calls */
	struct rpc_wait_queue wait; /* RPC call delay queue */
	};

	struct nfs_seqid {
	struct nfs_seqid_counter *sequence;
	struct list_head list;
	struct rpc_task *task;
	};

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

	/*
	* 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_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;
	seqcount_t so_reclaim_seqcount;
	struct mutex so_delegreturn_mutex;
	};

	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 0
	#define NFS_LOCK_LOST 1
	unsigned long ls_flags;
	struct nfs_seqid_counter ls_seqid;
	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_OPEN_STATE, /* OPEN stateid is set */
	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 */
	NFS_STATE_RECOVERY_FAILED, /* OPEN stateid state recovery failed */
	};

	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 inode *inode;
	};

	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 *);
	int (reclaim_complete)(struct nfs_client , struct rpc_cred *);
	int (detect_trunking)(struct nfs_client , struct nfs_client **,
	struct rpc_cred *);
	};

	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;

	/* dir.c */
	int nfs_atomic_open(struct inode , struct dentry , struct file *,
	unsigned, umode_t, int *);

	/* super.c */
	extern struct file_system_type nfs4_fs_type;

	/* nfs4namespace.c */
	rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *);
	struct rpc_clnt nfs4_create_sec_client(struct rpc_clnt , struct inode , struct qstr );
	struct vfsmount nfs4_submount(struct nfs_server , struct dentry *,
	struct nfs_fh , struct nfs_fattr );
	int nfs4_replace_transport(struct nfs_server *server,
	const struct nfs4_fs_locations *locations);

	/* 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_get_rootfh(struct nfs_server , struct nfs_fh , struct nfs_fsinfo *, bool);
	extern int nfs4_proc_bind_conn_to_session(struct nfs_client , struct rpc_cred cred);
	extern int nfs4_proc_exchange_id(struct nfs_client clp, struct rpc_cred cred);
	extern int nfs4_destroy_clientid(struct nfs_client *clp);
	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);
	extern int nfs4_server_capabilities(struct nfs_server server, struct nfs_fh fhandle);
	extern int nfs4_proc_fs_locations(struct rpc_clnt , struct inode , const struct qstr *,
	struct nfs4_fs_locations , struct page );
	extern struct rpc_clnt nfs4_proc_lookup_mountpoint(struct inode , struct qstr *,
	struct nfs_fh , struct nfs_fattr );
	extern int nfs4_proc_secinfo(struct inode , const struct qstr , struct nfs4_secinfo_flavors *);
	extern const struct xattr_handler *nfs4_xattr_handlers[];
	extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
	const struct nfs_open_context *ctx,
	const struct nfs_lock_context *l_ctx,
	fmode_t fmode);

	#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 nfs41_setup_sequence(struct nfs4_session *session,
	struct nfs4_sequence_args args, struct nfs4_sequence_res res,
	struct rpc_task *task);
	extern int nfs4_proc_create_session(struct nfs_client , struct rpc_cred );
	extern int nfs4_proc_destroy_session(struct nfs4_session , struct rpc_cred );
	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;
	}

	static inline bool
	_nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
	struct rpc_clnt *clntp, struct rpc_message msg)
	{
	struct rpc_cred *newcred = NULL;
	rpc_authflavor_t flavor;

	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
	spin_lock(&clp->cl_lock);
	if (clp->cl_machine_cred != NULL)
	/* don't call get_rpccred on the machine cred -
	* a reference will be held for life of clp */
	newcred = clp->cl_machine_cred;
	spin_unlock(&clp->cl_lock);
	msg->rpc_cred = newcred;

	flavor = clp->cl_rpcclient->cl_auth->au_flavor;
	WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
	flavor != RPC_AUTH_GSS_KRB5P);
	*clntp = clp->cl_rpcclient;

	return true;
	}
	return false;
	}

	/*
	* Function responsible for determining if an rpc_message should use the
	* machine cred under SP4_MACH_CRED and if so switching the credential and
	* authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
	* Should be called before rpc_call_sync/rpc_call_async.
	*/
	static inline void
	nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
	struct rpc_clnt *clntp, struct rpc_message msg)
	{
	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
	}

	/*
	* Special wrapper to nfs4_state_protect for write.
	* If WRITE can use machine cred but COMMIT cannot, make sure all writes
	* that use machine cred use NFS_FILE_SYNC.
	*/
	static inline void
	nfs4_state_protect_write(struct nfs_client clp, struct rpc_clnt *clntp,
	struct rpc_message msg, struct nfs_write_data wdata)
	{
	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
	!test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
	wdata->args.stable = NFS_FILE_SYNC;
	}
	#else /* CONFIG_NFS_v4_1 */
	static inline struct nfs4_session nfs4_get_session(const struct nfs_server server)
	{
	return NULL;
	}

	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;
	}

	static inline void
	nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
	struct rpc_clnt *clntp, struct rpc_message msg)
	{
	}

	static inline void
	nfs4_state_protect_write(struct nfs_client clp, struct rpc_clnt *clntp,
	struct rpc_message msg, struct nfs_write_data wdata)
	{
	}
	#endif /* CONFIG_NFS_V4_1 */

	extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];

	extern const u32 nfs4_fattr_bitmap[3];
	extern const u32 nfs4_statfs_bitmap[3];
	extern const u32 nfs4_pathconf_bitmap[3];
	extern const u32 nfs4_fsinfo_bitmap[3];
	extern const u32 nfs4_fs_locations_bitmap[3];

	void nfs40_shutdown_client(struct nfs_client *);
	void nfs41_shutdown_client(struct nfs_client *);
	int nfs40_init_client(struct nfs_client *);
	int nfs41_init_client(struct nfs_client *);
	void nfs4_free_client(struct nfs_client *);

	struct nfs_client nfs4_alloc_client(const struct nfs_client_initdata );

	/* 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_clid_cred(struct nfs_client clp);
	struct rpc_cred nfs4_get_machine_cred_locked(struct nfs_client clp);
	struct rpc_cred nfs4_get_renew_cred_locked(struct nfs_client clp);
	int nfs4_discover_server_trunking(struct nfs_client *clp,
	struct nfs_client **);
	int nfs40_discover_server_trunking(struct nfs_client *clp,
	struct nfs_client *, struct rpc_cred );
	#if defined(CONFIG_NFS_V4_1)
	int nfs41_discover_server_trunking(struct nfs_client *clp,
	struct nfs_client *, struct rpc_cred );
	extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
	extern void nfs41_server_notify_target_slotid_update(struct nfs_client *clp);
	extern void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp);

	#else
	static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
	{
	}
	#endif /* CONFIG_NFS_V4_1 */

	extern struct nfs4_state_owner nfs4_get_state_owner(struct nfs_server , struct rpc_cred *, gfp_t);
	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 nfs_inode_find_state_and_recover(struct inode *inode,
	const nfs4_stateid *stateid);
	extern void nfs4_schedule_lease_recovery(struct nfs_client *);
	extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
	extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
	extern void nfs4_schedule_state_manager(struct nfs_client *);
	extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
	extern int 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_server_scope(struct nfs_client *,
	struct nfs41_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 int nfs4_select_rw_stateid(nfs4_stateid , struct nfs4_state ,
	fmode_t, const struct nfs_lockowner *);

	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 void nfs4_free_lock_state(struct nfs_server server, struct nfs4_lock_state lsp);

	extern const nfs4_stateid zero_stateid;

	/* nfs4super.c */
	struct nfs_mount_info;
	extern struct nfs_subversion nfs_v4;
	struct dentry nfs4_try_mount(int, const char , struct nfs_mount_info , struct nfs_subversion );
	extern bool nfs4_disable_idmapping;
	extern unsigned short max_session_slots;
	extern unsigned short send_implementation_id;
	extern bool recover_lost_locks;

	#define NFS4_CLIENT_ID_UNIQ_LEN (64)
	extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];

	/* nfs4sysctl.c */
	#ifdef CONFIG_SYSCTL
	int nfs4_register_sysctl(void);
	void nfs4_unregister_sysctl(void);
	#else
	static inline int nfs4_register_sysctl(void)
	{
	return 0;
	}

	static inline void nfs4_unregister_sysctl(void)
	{
	}
	#endif

	/* 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;

	static inline void nfs4_stateid_copy(nfs4_stateid dst, const nfs4_stateid src)
	{
	memcpy(dst, src, sizeof(*dst));
	}

	static inline bool nfs4_stateid_match(const nfs4_stateid dst, const nfs4_stateid src)
	{
	return memcmp(dst, src, sizeof(*dst)) == 0;
	}

	static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
	{
	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
	}

	#else

	#define nfs4_close_state(a, b) do { } while (0)
	#define nfs4_close_sync(a, b) do { } while (0)
	#define nfs4_state_protect(a, b, c, d) do { } while (0)
	#define nfs4_state_protect_write(a, b, c, d) do { } while (0)

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