xref: /openbmc/linux/fs/nfs/nfs4_fs.h (revision 92b19ff5)
1 /*
2  * linux/fs/nfs/nfs4_fs.h
3  *
4  * Copyright (C) 2005 Trond Myklebust
5  *
6  * NFSv4-specific filesystem definitions and declarations
7  */
8 
9 #ifndef __LINUX_FS_NFS_NFS4_FS_H
10 #define __LINUX_FS_NFS_NFS4_FS_H
11 
12 #if defined(CONFIG_NFS_V4_2)
13 #define NFS4_MAX_MINOR_VERSION 2
14 #elif defined(CONFIG_NFS_V4_1)
15 #define NFS4_MAX_MINOR_VERSION 1
16 #else
17 #define NFS4_MAX_MINOR_VERSION 0
18 #endif
19 
20 #if IS_ENABLED(CONFIG_NFS_V4)
21 
22 #define NFS4_MAX_LOOP_ON_RECOVER (10)
23 
24 #include <linux/seqlock.h>
25 
26 struct idmap;
27 
28 enum nfs4_client_state {
29 	NFS4CLNT_MANAGER_RUNNING  = 0,
30 	NFS4CLNT_CHECK_LEASE,
31 	NFS4CLNT_LEASE_EXPIRED,
32 	NFS4CLNT_RECLAIM_REBOOT,
33 	NFS4CLNT_RECLAIM_NOGRACE,
34 	NFS4CLNT_DELEGRETURN,
35 	NFS4CLNT_SESSION_RESET,
36 	NFS4CLNT_LEASE_CONFIRM,
37 	NFS4CLNT_SERVER_SCOPE_MISMATCH,
38 	NFS4CLNT_PURGE_STATE,
39 	NFS4CLNT_BIND_CONN_TO_SESSION,
40 	NFS4CLNT_MOVED,
41 	NFS4CLNT_LEASE_MOVED,
42 };
43 
44 #define NFS4_RENEW_TIMEOUT		0x01
45 #define NFS4_RENEW_DELEGATION_CB	0x02
46 
47 struct nfs_seqid_counter;
48 struct nfs4_minor_version_ops {
49 	u32	minor_version;
50 	unsigned init_caps;
51 
52 	int	(*init_client)(struct nfs_client *);
53 	void	(*shutdown_client)(struct nfs_client *);
54 	bool	(*match_stateid)(const nfs4_stateid *,
55 			const nfs4_stateid *);
56 	int	(*find_root_sec)(struct nfs_server *, struct nfs_fh *,
57 			struct nfs_fsinfo *);
58 	void	(*free_lock_state)(struct nfs_server *,
59 			struct nfs4_lock_state *);
60 	struct nfs_seqid *
61 		(*alloc_seqid)(struct nfs_seqid_counter *, gfp_t);
62 	const struct rpc_call_ops *call_sync_ops;
63 	const struct nfs4_state_recovery_ops *reboot_recovery_ops;
64 	const struct nfs4_state_recovery_ops *nograce_recovery_ops;
65 	const struct nfs4_state_maintenance_ops *state_renewal_ops;
66 	const struct nfs4_mig_recovery_ops *mig_recovery_ops;
67 };
68 
69 #define NFS_SEQID_CONFIRMED 1
70 struct nfs_seqid_counter {
71 	ktime_t create_time;
72 	int owner_id;
73 	int flags;
74 	u32 counter;
75 	spinlock_t lock;		/* Protects the list */
76 	struct list_head list;		/* Defines sequence of RPC calls */
77 	struct rpc_wait_queue	wait;	/* RPC call delay queue */
78 };
79 
80 struct nfs_seqid {
81 	struct nfs_seqid_counter *sequence;
82 	struct list_head list;
83 	struct rpc_task *task;
84 };
85 
86 static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
87 {
88 	if (seqid_mutating_err(-status))
89 		seqid->flags |= NFS_SEQID_CONFIRMED;
90 }
91 
92 /*
93  * NFS4 state_owners and lock_owners are simply labels for ordered
94  * sequences of RPC calls. Their sole purpose is to provide once-only
95  * semantics by allowing the server to identify replayed requests.
96  */
97 struct nfs4_state_owner {
98 	struct nfs_server    *so_server;
99 	struct list_head     so_lru;
100 	unsigned long        so_expires;
101 	struct rb_node	     so_server_node;
102 
103 	struct rpc_cred	     *so_cred;	 /* Associated cred */
104 
105 	spinlock_t	     so_lock;
106 	atomic_t	     so_count;
107 	unsigned long	     so_flags;
108 	struct list_head     so_states;
109 	struct nfs_seqid_counter so_seqid;
110 	seqcount_t	     so_reclaim_seqcount;
111 	struct mutex	     so_delegreturn_mutex;
112 };
113 
114 enum {
115 	NFS_OWNER_RECLAIM_REBOOT,
116 	NFS_OWNER_RECLAIM_NOGRACE
117 };
118 
119 #define NFS_LOCK_NEW		0
120 #define NFS_LOCK_RECLAIM	1
121 #define NFS_LOCK_EXPIRED	2
122 
123 /*
124  * struct nfs4_state maintains the client-side state for a given
125  * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
126  *
127  * OPEN:
128  * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
129  * we need to know how many files are open for reading or writing on a
130  * given inode. This information too is stored here.
131  *
132  * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
133  */
134 
135 struct nfs4_lock_state {
136 	struct list_head	ls_locks;	/* Other lock stateids */
137 	struct nfs4_state *	ls_state;	/* Pointer to open state */
138 #define NFS_LOCK_INITIALIZED 0
139 #define NFS_LOCK_LOST        1
140 	unsigned long		ls_flags;
141 	struct nfs_seqid_counter	ls_seqid;
142 	nfs4_stateid		ls_stateid;
143 	atomic_t		ls_count;
144 	fl_owner_t		ls_owner;
145 };
146 
147 /* bits for nfs4_state->flags */
148 enum {
149 	LK_STATE_IN_USE,
150 	NFS_DELEGATED_STATE,		/* Current stateid is delegation */
151 	NFS_OPEN_STATE,			/* OPEN stateid is set */
152 	NFS_O_RDONLY_STATE,		/* OPEN stateid has read-only state */
153 	NFS_O_WRONLY_STATE,		/* OPEN stateid has write-only state */
154 	NFS_O_RDWR_STATE,		/* OPEN stateid has read/write state */
155 	NFS_STATE_RECLAIM_REBOOT,	/* OPEN stateid server rebooted */
156 	NFS_STATE_RECLAIM_NOGRACE,	/* OPEN stateid needs to recover state */
157 	NFS_STATE_POSIX_LOCKS,		/* Posix locks are supported */
158 	NFS_STATE_RECOVERY_FAILED,	/* OPEN stateid state recovery failed */
159 };
160 
161 struct nfs4_state {
162 	struct list_head open_states;	/* List of states for the same state_owner */
163 	struct list_head inode_states;	/* List of states for the same inode */
164 	struct list_head lock_states;	/* List of subservient lock stateids */
165 
166 	struct nfs4_state_owner *owner;	/* Pointer to the open owner */
167 	struct inode *inode;		/* Pointer to the inode */
168 
169 	unsigned long flags;		/* Do we hold any locks? */
170 	spinlock_t state_lock;		/* Protects the lock_states list */
171 
172 	seqlock_t seqlock;		/* Protects the stateid/open_stateid */
173 	nfs4_stateid stateid;		/* Current stateid: may be delegation */
174 	nfs4_stateid open_stateid;	/* OPEN stateid */
175 
176 	/* The following 3 fields are protected by owner->so_lock */
177 	unsigned int n_rdonly;		/* Number of read-only references */
178 	unsigned int n_wronly;		/* Number of write-only references */
179 	unsigned int n_rdwr;		/* Number of read/write references */
180 	fmode_t state;			/* State on the server (R,W, or RW) */
181 	atomic_t count;
182 };
183 
184 
185 struct nfs4_exception {
186 	long timeout;
187 	int retry;
188 	struct nfs4_state *state;
189 	struct inode *inode;
190 };
191 
192 struct nfs4_state_recovery_ops {
193 	int owner_flag_bit;
194 	int state_flag_bit;
195 	int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
196 	int (*recover_lock)(struct nfs4_state *, struct file_lock *);
197 	int (*establish_clid)(struct nfs_client *, struct rpc_cred *);
198 	int (*reclaim_complete)(struct nfs_client *, struct rpc_cred *);
199 	int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
200 		struct rpc_cred *);
201 };
202 
203 struct nfs4_state_maintenance_ops {
204 	int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);
205 	struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);
206 	int (*renew_lease)(struct nfs_client *, struct rpc_cred *);
207 };
208 
209 struct nfs4_mig_recovery_ops {
210 	int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
211 		struct page *, struct rpc_cred *);
212 	int (*fsid_present)(struct inode *, struct rpc_cred *);
213 };
214 
215 extern const struct dentry_operations nfs4_dentry_operations;
216 
217 /* dir.c */
218 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
219 		    unsigned, umode_t, int *);
220 
221 /* super.c */
222 extern struct file_system_type nfs4_fs_type;
223 
224 /* nfs4namespace.c */
225 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *, struct qstr *);
226 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
227 			       struct nfs_fh *, struct nfs_fattr *);
228 int nfs4_replace_transport(struct nfs_server *server,
229 				const struct nfs4_fs_locations *locations);
230 
231 /* nfs4proc.c */
232 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
233 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
234 			  struct rpc_message *, struct nfs4_sequence_args *,
235 			  struct nfs4_sequence_res *, int);
236 extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int);
237 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
238 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
239 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
240 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
241 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
242 extern int nfs4_destroy_clientid(struct nfs_client *clp);
243 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
244 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
245 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
246 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
247 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
248 				  struct nfs4_fs_locations *, struct page *);
249 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
250 		struct page *page, struct rpc_cred *);
251 extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
252 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, struct qstr *,
253 			    struct nfs_fh *, struct nfs_fattr *);
254 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
255 extern const struct xattr_handler *nfs4_xattr_handlers[];
256 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
257 		const struct nfs_open_context *ctx,
258 		const struct nfs_lock_context *l_ctx,
259 		fmode_t fmode);
260 
261 #if defined(CONFIG_NFS_V4_1)
262 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
263 {
264 	return server->nfs_client->cl_session;
265 }
266 
267 extern int nfs41_setup_sequence(struct nfs4_session *session,
268 		struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
269 		struct rpc_task *task);
270 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
271 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
272 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
273 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
274 		struct nfs_fsinfo *fsinfo);
275 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
276 				  bool sync);
277 
278 static inline bool
279 is_ds_only_client(struct nfs_client *clp)
280 {
281 	return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
282 		EXCHGID4_FLAG_USE_PNFS_DS;
283 }
284 
285 static inline bool
286 is_ds_client(struct nfs_client *clp)
287 {
288 	return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
289 }
290 
291 static inline bool
292 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
293 		    struct rpc_clnt **clntp, struct rpc_message *msg)
294 {
295 	struct rpc_cred *newcred = NULL;
296 	rpc_authflavor_t flavor;
297 
298 	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
299 		spin_lock(&clp->cl_lock);
300 		if (clp->cl_machine_cred != NULL)
301 			/* don't call get_rpccred on the machine cred -
302 			 * a reference will be held for life of clp */
303 			newcred = clp->cl_machine_cred;
304 		spin_unlock(&clp->cl_lock);
305 		msg->rpc_cred = newcred;
306 
307 		flavor = clp->cl_rpcclient->cl_auth->au_flavor;
308 		WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
309 			     flavor != RPC_AUTH_GSS_KRB5P);
310 		*clntp = clp->cl_rpcclient;
311 
312 		return true;
313 	}
314 	return false;
315 }
316 
317 /*
318  * Function responsible for determining if an rpc_message should use the
319  * machine cred under SP4_MACH_CRED and if so switching the credential and
320  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
321  * Should be called before rpc_call_sync/rpc_call_async.
322  */
323 static inline void
324 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
325 		   struct rpc_clnt **clntp, struct rpc_message *msg)
326 {
327 	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
328 }
329 
330 /*
331  * Special wrapper to nfs4_state_protect for write.
332  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
333  * that use machine cred use NFS_FILE_SYNC.
334  */
335 static inline void
336 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
337 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
338 {
339 	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
340 	    !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
341 		hdr->args.stable = NFS_FILE_SYNC;
342 }
343 #else /* CONFIG_NFS_v4_1 */
344 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
345 {
346 	return NULL;
347 }
348 
349 static inline bool
350 is_ds_only_client(struct nfs_client *clp)
351 {
352 	return false;
353 }
354 
355 static inline bool
356 is_ds_client(struct nfs_client *clp)
357 {
358 	return false;
359 }
360 
361 static inline void
362 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
363 		   struct rpc_clnt **clntp, struct rpc_message *msg)
364 {
365 }
366 
367 static inline void
368 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
369 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
370 {
371 }
372 #endif /* CONFIG_NFS_V4_1 */
373 
374 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
375 
376 extern const u32 nfs4_fattr_bitmap[3];
377 extern const u32 nfs4_statfs_bitmap[3];
378 extern const u32 nfs4_pathconf_bitmap[3];
379 extern const u32 nfs4_fsinfo_bitmap[3];
380 extern const u32 nfs4_fs_locations_bitmap[3];
381 
382 void nfs40_shutdown_client(struct nfs_client *);
383 void nfs41_shutdown_client(struct nfs_client *);
384 int nfs40_init_client(struct nfs_client *);
385 int nfs41_init_client(struct nfs_client *);
386 void nfs4_free_client(struct nfs_client *);
387 
388 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
389 
390 /* nfs4renewd.c */
391 extern void nfs4_schedule_state_renewal(struct nfs_client *);
392 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
393 extern void nfs4_kill_renewd(struct nfs_client *);
394 extern void nfs4_renew_state(struct work_struct *);
395 
396 /* nfs4state.c */
397 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
398 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
399 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
400 int nfs4_discover_server_trunking(struct nfs_client *clp,
401 			struct nfs_client **);
402 int nfs40_discover_server_trunking(struct nfs_client *clp,
403 			struct nfs_client **, struct rpc_cred *);
404 #if defined(CONFIG_NFS_V4_1)
405 int nfs41_discover_server_trunking(struct nfs_client *clp,
406 			struct nfs_client **, struct rpc_cred *);
407 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
408 extern void nfs41_server_notify_target_slotid_update(struct nfs_client *clp);
409 extern void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp);
410 
411 #else
412 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
413 {
414 }
415 #endif /* CONFIG_NFS_V4_1 */
416 
417 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
418 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
419 extern void nfs4_purge_state_owners(struct nfs_server *);
420 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
421 extern void nfs4_put_open_state(struct nfs4_state *);
422 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
423 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
424 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
425 extern void nfs_inode_find_state_and_recover(struct inode *inode,
426 		const nfs4_stateid *stateid);
427 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
428 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
429 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
430 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
431 extern void nfs4_schedule_state_manager(struct nfs_client *);
432 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
433 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
434 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
435 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
436 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
437 extern void nfs41_handle_server_scope(struct nfs_client *,
438 				      struct nfs41_server_scope **);
439 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
440 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
441 extern int nfs4_select_rw_stateid(nfs4_stateid *, struct nfs4_state *,
442 		fmode_t, const struct nfs_lockowner *);
443 
444 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
445 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
446 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
447 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
448 extern void nfs_release_seqid(struct nfs_seqid *seqid);
449 extern void nfs_free_seqid(struct nfs_seqid *seqid);
450 extern int nfs40_setup_sequence(struct nfs4_slot_table *tbl,
451 				struct nfs4_sequence_args *args,
452 				struct nfs4_sequence_res *res,
453 				struct rpc_task *task);
454 extern int nfs4_sequence_done(struct rpc_task *task,
455 			      struct nfs4_sequence_res *res);
456 
457 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
458 
459 extern const nfs4_stateid zero_stateid;
460 
461 /* nfs4super.c */
462 struct nfs_mount_info;
463 extern struct nfs_subversion nfs_v4;
464 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
465 extern bool nfs4_disable_idmapping;
466 extern unsigned short max_session_slots;
467 extern unsigned short send_implementation_id;
468 extern bool recover_lost_locks;
469 
470 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
471 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
472 
473 /* nfs4sysctl.c */
474 #ifdef CONFIG_SYSCTL
475 int nfs4_register_sysctl(void);
476 void nfs4_unregister_sysctl(void);
477 #else
478 static inline int nfs4_register_sysctl(void)
479 {
480 	return 0;
481 }
482 
483 static inline void nfs4_unregister_sysctl(void)
484 {
485 }
486 #endif
487 
488 /* nfs4xdr.c */
489 extern struct rpc_procinfo nfs4_procedures[];
490 
491 struct nfs4_mount_data;
492 
493 /* callback_xdr.c */
494 extern struct svc_version nfs4_callback_version1;
495 extern struct svc_version nfs4_callback_version4;
496 
497 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
498 {
499 	memcpy(dst, src, sizeof(*dst));
500 }
501 
502 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
503 {
504 	return memcmp(dst, src, sizeof(*dst)) == 0;
505 }
506 
507 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
508 {
509 	return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
510 }
511 
512 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
513 {
514 	return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
515 }
516 
517 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
518 {
519 	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
520 }
521 
522 #else
523 
524 #define nfs4_close_state(a, b) do { } while (0)
525 #define nfs4_close_sync(a, b) do { } while (0)
526 #define nfs4_state_protect(a, b, c, d) do { } while (0)
527 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
528 
529 #endif /* CONFIG_NFS_V4 */
530 #endif /* __LINUX_FS_NFS_NFS4_FS.H */
531