xref: /openbmc/linux/fs/nfs/nfs4_fs.h (revision 0da85d1e)
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 int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
237 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
238 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
239 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
240 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
241 extern int nfs4_destroy_clientid(struct nfs_client *clp);
242 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
243 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
244 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
245 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
246 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
247 				  struct nfs4_fs_locations *, struct page *);
248 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
249 		struct page *page, struct rpc_cred *);
250 extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
251 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, struct qstr *,
252 			    struct nfs_fh *, struct nfs_fattr *);
253 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
254 extern const struct xattr_handler *nfs4_xattr_handlers[];
255 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
256 		const struct nfs_open_context *ctx,
257 		const struct nfs_lock_context *l_ctx,
258 		fmode_t fmode);
259 
260 #if defined(CONFIG_NFS_V4_1)
261 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
262 {
263 	return server->nfs_client->cl_session;
264 }
265 
266 extern int nfs41_setup_sequence(struct nfs4_session *session,
267 		struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
268 		struct rpc_task *task);
269 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
270 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
271 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
272 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
273 		struct nfs_fsinfo *fsinfo);
274 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
275 				  bool sync);
276 
277 static inline bool
278 is_ds_only_client(struct nfs_client *clp)
279 {
280 	return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
281 		EXCHGID4_FLAG_USE_PNFS_DS;
282 }
283 
284 static inline bool
285 is_ds_client(struct nfs_client *clp)
286 {
287 	return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
288 }
289 
290 static inline bool
291 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
292 		    struct rpc_clnt **clntp, struct rpc_message *msg)
293 {
294 	struct rpc_cred *newcred = NULL;
295 	rpc_authflavor_t flavor;
296 
297 	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
298 		spin_lock(&clp->cl_lock);
299 		if (clp->cl_machine_cred != NULL)
300 			/* don't call get_rpccred on the machine cred -
301 			 * a reference will be held for life of clp */
302 			newcred = clp->cl_machine_cred;
303 		spin_unlock(&clp->cl_lock);
304 		msg->rpc_cred = newcred;
305 
306 		flavor = clp->cl_rpcclient->cl_auth->au_flavor;
307 		WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
308 			     flavor != RPC_AUTH_GSS_KRB5P);
309 		*clntp = clp->cl_rpcclient;
310 
311 		return true;
312 	}
313 	return false;
314 }
315 
316 /*
317  * Function responsible for determining if an rpc_message should use the
318  * machine cred under SP4_MACH_CRED and if so switching the credential and
319  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
320  * Should be called before rpc_call_sync/rpc_call_async.
321  */
322 static inline void
323 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
324 		   struct rpc_clnt **clntp, struct rpc_message *msg)
325 {
326 	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
327 }
328 
329 /*
330  * Special wrapper to nfs4_state_protect for write.
331  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
332  * that use machine cred use NFS_FILE_SYNC.
333  */
334 static inline void
335 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
336 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
337 {
338 	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
339 	    !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
340 		hdr->args.stable = NFS_FILE_SYNC;
341 }
342 #else /* CONFIG_NFS_v4_1 */
343 static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *server)
344 {
345 	return NULL;
346 }
347 
348 static inline bool
349 is_ds_only_client(struct nfs_client *clp)
350 {
351 	return false;
352 }
353 
354 static inline bool
355 is_ds_client(struct nfs_client *clp)
356 {
357 	return false;
358 }
359 
360 static inline void
361 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
362 		   struct rpc_clnt **clntp, struct rpc_message *msg)
363 {
364 }
365 
366 static inline void
367 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
368 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
369 {
370 }
371 #endif /* CONFIG_NFS_V4_1 */
372 
373 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
374 
375 extern const u32 nfs4_fattr_bitmap[3];
376 extern const u32 nfs4_statfs_bitmap[3];
377 extern const u32 nfs4_pathconf_bitmap[3];
378 extern const u32 nfs4_fsinfo_bitmap[3];
379 extern const u32 nfs4_fs_locations_bitmap[3];
380 
381 void nfs40_shutdown_client(struct nfs_client *);
382 void nfs41_shutdown_client(struct nfs_client *);
383 int nfs40_init_client(struct nfs_client *);
384 int nfs41_init_client(struct nfs_client *);
385 void nfs4_free_client(struct nfs_client *);
386 
387 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
388 
389 /* nfs4renewd.c */
390 extern void nfs4_schedule_state_renewal(struct nfs_client *);
391 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
392 extern void nfs4_kill_renewd(struct nfs_client *);
393 extern void nfs4_renew_state(struct work_struct *);
394 
395 /* nfs4state.c */
396 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
397 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
398 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
399 int nfs4_discover_server_trunking(struct nfs_client *clp,
400 			struct nfs_client **);
401 int nfs40_discover_server_trunking(struct nfs_client *clp,
402 			struct nfs_client **, struct rpc_cred *);
403 #if defined(CONFIG_NFS_V4_1)
404 int nfs41_discover_server_trunking(struct nfs_client *clp,
405 			struct nfs_client **, struct rpc_cred *);
406 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
407 extern void nfs41_server_notify_target_slotid_update(struct nfs_client *clp);
408 extern void nfs41_server_notify_highest_slotid_update(struct nfs_client *clp);
409 
410 #else
411 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
412 {
413 }
414 #endif /* CONFIG_NFS_V4_1 */
415 
416 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
417 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
418 extern void nfs4_purge_state_owners(struct nfs_server *);
419 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
420 extern void nfs4_put_open_state(struct nfs4_state *);
421 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
422 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
423 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
424 extern void nfs_inode_find_state_and_recover(struct inode *inode,
425 		const nfs4_stateid *stateid);
426 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
427 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
428 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
429 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
430 extern void nfs4_schedule_state_manager(struct nfs_client *);
431 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
432 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
433 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
434 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
435 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
436 extern void nfs41_handle_server_scope(struct nfs_client *,
437 				      struct nfs41_server_scope **);
438 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
439 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
440 extern int nfs4_select_rw_stateid(nfs4_stateid *, struct nfs4_state *,
441 		fmode_t, const struct nfs_lockowner *);
442 
443 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
444 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
445 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
446 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
447 extern void nfs_release_seqid(struct nfs_seqid *seqid);
448 extern void nfs_free_seqid(struct nfs_seqid *seqid);
449 extern int nfs40_setup_sequence(struct nfs4_slot_table *tbl,
450 				struct nfs4_sequence_args *args,
451 				struct nfs4_sequence_res *res,
452 				struct rpc_task *task);
453 extern int nfs4_sequence_done(struct rpc_task *task,
454 			      struct nfs4_sequence_res *res);
455 
456 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
457 
458 extern const nfs4_stateid zero_stateid;
459 
460 /* nfs4super.c */
461 struct nfs_mount_info;
462 extern struct nfs_subversion nfs_v4;
463 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
464 extern bool nfs4_disable_idmapping;
465 extern unsigned short max_session_slots;
466 extern unsigned short send_implementation_id;
467 extern bool recover_lost_locks;
468 
469 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
470 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
471 
472 /* nfs4sysctl.c */
473 #ifdef CONFIG_SYSCTL
474 int nfs4_register_sysctl(void);
475 void nfs4_unregister_sysctl(void);
476 #else
477 static inline int nfs4_register_sysctl(void)
478 {
479 	return 0;
480 }
481 
482 static inline void nfs4_unregister_sysctl(void)
483 {
484 }
485 #endif
486 
487 /* nfs4xdr.c */
488 extern struct rpc_procinfo nfs4_procedures[];
489 
490 struct nfs4_mount_data;
491 
492 /* callback_xdr.c */
493 extern struct svc_version nfs4_callback_version1;
494 extern struct svc_version nfs4_callback_version4;
495 
496 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
497 {
498 	memcpy(dst, src, sizeof(*dst));
499 }
500 
501 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
502 {
503 	return memcmp(dst, src, sizeof(*dst)) == 0;
504 }
505 
506 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
507 {
508 	return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
509 }
510 
511 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
512 {
513 	return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
514 }
515 
516 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
517 {
518 	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
519 }
520 
521 #else
522 
523 #define nfs4_close_state(a, b) do { } while (0)
524 #define nfs4_close_sync(a, b) do { } while (0)
525 #define nfs4_state_protect(a, b, c, d) do { } while (0)
526 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
527 
528 #endif /* CONFIG_NFS_V4 */
529 #endif /* __LINUX_FS_NFS_NFS4_FS.H */
530