xref: /openbmc/linux/fs/nfs/nfs4_fs.h (revision e5c86679)
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 	NFS4CLNT_DELEGATION_EXPIRED,
43 };
44 
45 #define NFS4_RENEW_TIMEOUT		0x01
46 #define NFS4_RENEW_DELEGATION_CB	0x02
47 
48 struct nfs_seqid_counter;
49 struct nfs4_minor_version_ops {
50 	u32	minor_version;
51 	unsigned init_caps;
52 
53 	int	(*init_client)(struct nfs_client *);
54 	void	(*shutdown_client)(struct nfs_client *);
55 	bool	(*match_stateid)(const nfs4_stateid *,
56 			const nfs4_stateid *);
57 	int	(*find_root_sec)(struct nfs_server *, struct nfs_fh *,
58 			struct nfs_fsinfo *);
59 	void	(*free_lock_state)(struct nfs_server *,
60 			struct nfs4_lock_state *);
61 	int	(*test_and_free_expired)(struct nfs_server *,
62 			nfs4_stateid *, struct rpc_cred *);
63 	struct nfs_seqid *
64 		(*alloc_seqid)(struct nfs_seqid_counter *, gfp_t);
65 	int	(*session_trunk)(struct rpc_clnt *, struct rpc_xprt *, void *);
66 	const struct rpc_call_ops *call_sync_ops;
67 	const struct nfs4_state_recovery_ops *reboot_recovery_ops;
68 	const struct nfs4_state_recovery_ops *nograce_recovery_ops;
69 	const struct nfs4_state_maintenance_ops *state_renewal_ops;
70 	const struct nfs4_mig_recovery_ops *mig_recovery_ops;
71 };
72 
73 #define NFS_SEQID_CONFIRMED 1
74 struct nfs_seqid_counter {
75 	ktime_t create_time;
76 	int owner_id;
77 	int flags;
78 	u32 counter;
79 	spinlock_t lock;		/* Protects the list */
80 	struct list_head list;		/* Defines sequence of RPC calls */
81 	struct rpc_wait_queue	wait;	/* RPC call delay queue */
82 };
83 
84 struct nfs_seqid {
85 	struct nfs_seqid_counter *sequence;
86 	struct list_head list;
87 	struct rpc_task *task;
88 };
89 
90 static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
91 {
92 	if (seqid_mutating_err(-status))
93 		seqid->flags |= NFS_SEQID_CONFIRMED;
94 }
95 
96 /*
97  * NFS4 state_owners and lock_owners are simply labels for ordered
98  * sequences of RPC calls. Their sole purpose is to provide once-only
99  * semantics by allowing the server to identify replayed requests.
100  */
101 struct nfs4_state_owner {
102 	struct nfs_server    *so_server;
103 	struct list_head     so_lru;
104 	unsigned long        so_expires;
105 	struct rb_node	     so_server_node;
106 
107 	struct rpc_cred	     *so_cred;	 /* Associated cred */
108 
109 	spinlock_t	     so_lock;
110 	atomic_t	     so_count;
111 	unsigned long	     so_flags;
112 	struct list_head     so_states;
113 	struct nfs_seqid_counter so_seqid;
114 	seqcount_t	     so_reclaim_seqcount;
115 	struct mutex	     so_delegreturn_mutex;
116 };
117 
118 enum {
119 	NFS_OWNER_RECLAIM_REBOOT,
120 	NFS_OWNER_RECLAIM_NOGRACE
121 };
122 
123 #define NFS_LOCK_NEW		0
124 #define NFS_LOCK_RECLAIM	1
125 #define NFS_LOCK_EXPIRED	2
126 
127 /*
128  * struct nfs4_state maintains the client-side state for a given
129  * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
130  *
131  * OPEN:
132  * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
133  * we need to know how many files are open for reading or writing on a
134  * given inode. This information too is stored here.
135  *
136  * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
137  */
138 
139 struct nfs4_lock_state {
140 	struct list_head	ls_locks;	/* Other lock stateids */
141 	struct nfs4_state *	ls_state;	/* Pointer to open state */
142 #define NFS_LOCK_INITIALIZED 0
143 #define NFS_LOCK_LOST        1
144 	unsigned long		ls_flags;
145 	struct nfs_seqid_counter	ls_seqid;
146 	nfs4_stateid		ls_stateid;
147 	atomic_t		ls_count;
148 	fl_owner_t		ls_owner;
149 };
150 
151 /* bits for nfs4_state->flags */
152 enum {
153 	LK_STATE_IN_USE,
154 	NFS_DELEGATED_STATE,		/* Current stateid is delegation */
155 	NFS_OPEN_STATE,			/* OPEN stateid is set */
156 	NFS_O_RDONLY_STATE,		/* OPEN stateid has read-only state */
157 	NFS_O_WRONLY_STATE,		/* OPEN stateid has write-only state */
158 	NFS_O_RDWR_STATE,		/* OPEN stateid has read/write state */
159 	NFS_STATE_RECLAIM_REBOOT,	/* OPEN stateid server rebooted */
160 	NFS_STATE_RECLAIM_NOGRACE,	/* OPEN stateid needs to recover state */
161 	NFS_STATE_POSIX_LOCKS,		/* Posix locks are supported */
162 	NFS_STATE_RECOVERY_FAILED,	/* OPEN stateid state recovery failed */
163 	NFS_STATE_MAY_NOTIFY_LOCK,	/* server may CB_NOTIFY_LOCK */
164 };
165 
166 struct nfs4_state {
167 	struct list_head open_states;	/* List of states for the same state_owner */
168 	struct list_head inode_states;	/* List of states for the same inode */
169 	struct list_head lock_states;	/* List of subservient lock stateids */
170 
171 	struct nfs4_state_owner *owner;	/* Pointer to the open owner */
172 	struct inode *inode;		/* Pointer to the inode */
173 
174 	unsigned long flags;		/* Do we hold any locks? */
175 	spinlock_t state_lock;		/* Protects the lock_states list */
176 
177 	seqlock_t seqlock;		/* Protects the stateid/open_stateid */
178 	nfs4_stateid stateid;		/* Current stateid: may be delegation */
179 	nfs4_stateid open_stateid;	/* OPEN stateid */
180 
181 	/* The following 3 fields are protected by owner->so_lock */
182 	unsigned int n_rdonly;		/* Number of read-only references */
183 	unsigned int n_wronly;		/* Number of write-only references */
184 	unsigned int n_rdwr;		/* Number of read/write references */
185 	fmode_t state;			/* State on the server (R,W, or RW) */
186 	atomic_t count;
187 };
188 
189 
190 struct nfs4_exception {
191 	struct nfs4_state *state;
192 	struct inode *inode;
193 	nfs4_stateid *stateid;
194 	long timeout;
195 	unsigned char delay : 1,
196 		      recovering : 1,
197 		      retry : 1;
198 };
199 
200 struct nfs4_state_recovery_ops {
201 	int owner_flag_bit;
202 	int state_flag_bit;
203 	int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
204 	int (*recover_lock)(struct nfs4_state *, struct file_lock *);
205 	int (*establish_clid)(struct nfs_client *, struct rpc_cred *);
206 	int (*reclaim_complete)(struct nfs_client *, struct rpc_cred *);
207 	int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
208 		struct rpc_cred *);
209 };
210 
211 struct nfs4_add_xprt_data {
212 	struct nfs_client	*clp;
213 	struct rpc_cred		*cred;
214 };
215 
216 struct nfs4_state_maintenance_ops {
217 	int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);
218 	struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);
219 	int (*renew_lease)(struct nfs_client *, struct rpc_cred *);
220 };
221 
222 struct nfs4_mig_recovery_ops {
223 	int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
224 		struct page *, struct rpc_cred *);
225 	int (*fsid_present)(struct inode *, struct rpc_cred *);
226 };
227 
228 extern const struct dentry_operations nfs4_dentry_operations;
229 
230 /* dir.c */
231 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
232 		    unsigned, umode_t, int *);
233 
234 /* super.c */
235 extern struct file_system_type nfs4_fs_type;
236 
237 /* nfs4namespace.c */
238 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
239 					 const struct qstr *);
240 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
241 			       struct nfs_fh *, struct nfs_fattr *);
242 int nfs4_replace_transport(struct nfs_server *server,
243 				const struct nfs4_fs_locations *locations);
244 
245 /* nfs4proc.c */
246 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
247 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
248 			  struct rpc_message *, struct nfs4_sequence_args *,
249 			  struct nfs4_sequence_res *, int);
250 extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int);
251 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
252 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, struct rpc_cred *);
253 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
254 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, struct rpc_cred *cred);
255 extern int nfs4_proc_exchange_id(struct nfs_client *clp, struct rpc_cred *cred);
256 extern int nfs4_destroy_clientid(struct nfs_client *clp);
257 extern int nfs4_init_clientid(struct nfs_client *, struct rpc_cred *);
258 extern int nfs41_init_clientid(struct nfs_client *, struct rpc_cred *);
259 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
260 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
261 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
262 				  struct nfs4_fs_locations *, struct page *);
263 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
264 		struct page *page, struct rpc_cred *);
265 extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
266 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, const struct qstr *,
267 			    struct nfs_fh *, struct nfs_fattr *);
268 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
269 extern const struct xattr_handler *nfs4_xattr_handlers[];
270 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
271 		const struct nfs_open_context *ctx,
272 		const struct nfs_lock_context *l_ctx,
273 		fmode_t fmode);
274 
275 #if defined(CONFIG_NFS_V4_1)
276 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
277 extern int nfs4_proc_create_session(struct nfs_client *, struct rpc_cred *);
278 extern int nfs4_proc_destroy_session(struct nfs4_session *, struct rpc_cred *);
279 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
280 		struct nfs_fsinfo *fsinfo);
281 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
282 				  bool sync);
283 extern int nfs4_detect_session_trunking(struct nfs_client *clp,
284 		struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
285 
286 static inline bool
287 is_ds_only_client(struct nfs_client *clp)
288 {
289 	return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
290 		EXCHGID4_FLAG_USE_PNFS_DS;
291 }
292 
293 static inline bool
294 is_ds_client(struct nfs_client *clp)
295 {
296 	return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
297 }
298 
299 static inline bool
300 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
301 		    struct rpc_clnt **clntp, struct rpc_message *msg)
302 {
303 	struct rpc_cred *newcred = NULL;
304 	rpc_authflavor_t flavor;
305 
306 	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
307 		spin_lock(&clp->cl_lock);
308 		if (clp->cl_machine_cred != NULL)
309 			/* don't call get_rpccred on the machine cred -
310 			 * a reference will be held for life of clp */
311 			newcred = clp->cl_machine_cred;
312 		spin_unlock(&clp->cl_lock);
313 		msg->rpc_cred = newcred;
314 
315 		flavor = clp->cl_rpcclient->cl_auth->au_flavor;
316 		WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
317 			     flavor != RPC_AUTH_GSS_KRB5P);
318 		*clntp = clp->cl_rpcclient;
319 
320 		return true;
321 	}
322 	return false;
323 }
324 
325 /*
326  * Function responsible for determining if an rpc_message should use the
327  * machine cred under SP4_MACH_CRED and if so switching the credential and
328  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
329  * Should be called before rpc_call_sync/rpc_call_async.
330  */
331 static inline void
332 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
333 		   struct rpc_clnt **clntp, struct rpc_message *msg)
334 {
335 	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
336 }
337 
338 /*
339  * Special wrapper to nfs4_state_protect for write.
340  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
341  * that use machine cred use NFS_FILE_SYNC.
342  */
343 static inline void
344 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
345 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
346 {
347 	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
348 	    !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
349 		hdr->args.stable = NFS_FILE_SYNC;
350 }
351 #else /* CONFIG_NFS_v4_1 */
352 static inline bool
353 is_ds_only_client(struct nfs_client *clp)
354 {
355 	return false;
356 }
357 
358 static inline bool
359 is_ds_client(struct nfs_client *clp)
360 {
361 	return false;
362 }
363 
364 static inline void
365 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
366 		   struct rpc_clnt **clntp, struct rpc_message *msg)
367 {
368 }
369 
370 static inline void
371 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
372 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
373 {
374 }
375 #endif /* CONFIG_NFS_V4_1 */
376 
377 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
378 
379 extern const u32 nfs4_fattr_bitmap[3];
380 extern const u32 nfs4_statfs_bitmap[3];
381 extern const u32 nfs4_pathconf_bitmap[3];
382 extern const u32 nfs4_fsinfo_bitmap[3];
383 extern const u32 nfs4_fs_locations_bitmap[3];
384 
385 void nfs40_shutdown_client(struct nfs_client *);
386 void nfs41_shutdown_client(struct nfs_client *);
387 int nfs40_init_client(struct nfs_client *);
388 int nfs41_init_client(struct nfs_client *);
389 void nfs4_free_client(struct nfs_client *);
390 
391 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
392 
393 /* nfs4renewd.c */
394 extern void nfs4_schedule_state_renewal(struct nfs_client *);
395 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
396 extern void nfs4_kill_renewd(struct nfs_client *);
397 extern void nfs4_renew_state(struct work_struct *);
398 extern void nfs4_set_lease_period(struct nfs_client *clp,
399 		unsigned long lease,
400 		unsigned long lastrenewed);
401 
402 
403 /* nfs4state.c */
404 struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp);
405 struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp);
406 struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp);
407 int nfs4_discover_server_trunking(struct nfs_client *clp,
408 			struct nfs_client **);
409 int nfs40_discover_server_trunking(struct nfs_client *clp,
410 			struct nfs_client **, struct rpc_cred *);
411 #if defined(CONFIG_NFS_V4_1)
412 int nfs41_discover_server_trunking(struct nfs_client *clp,
413 			struct nfs_client **, struct rpc_cred *);
414 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
415 extern void nfs41_notify_server(struct nfs_client *);
416 #else
417 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
418 {
419 }
420 #endif /* CONFIG_NFS_V4_1 */
421 
422 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *, gfp_t);
423 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
424 extern void nfs4_purge_state_owners(struct nfs_server *);
425 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
426 extern void nfs4_put_open_state(struct nfs4_state *);
427 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
428 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
429 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
430 extern void nfs_inode_find_state_and_recover(struct inode *inode,
431 		const nfs4_stateid *stateid);
432 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
433 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
434 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
435 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
436 extern void nfs4_schedule_state_manager(struct nfs_client *);
437 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
438 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
439 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
440 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
441 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
442 extern void nfs41_handle_server_scope(struct nfs_client *,
443 				      struct nfs41_server_scope **);
444 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
445 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
446 extern int nfs4_select_rw_stateid(struct nfs4_state *, fmode_t,
447 		const struct nfs_lock_context *, nfs4_stateid *,
448 		struct rpc_cred **);
449 
450 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
451 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
452 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
453 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
454 extern void nfs_release_seqid(struct nfs_seqid *seqid);
455 extern void nfs_free_seqid(struct nfs_seqid *seqid);
456 extern int nfs4_setup_sequence(const struct nfs_client *client,
457 				struct nfs4_sequence_args *args,
458 				struct nfs4_sequence_res *res,
459 				struct rpc_task *task);
460 extern int nfs4_sequence_done(struct rpc_task *task,
461 			      struct nfs4_sequence_res *res);
462 
463 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
464 
465 extern const nfs4_stateid zero_stateid;
466 
467 /* nfs4super.c */
468 struct nfs_mount_info;
469 extern struct nfs_subversion nfs_v4;
470 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
471 extern bool nfs4_disable_idmapping;
472 extern unsigned short max_session_slots;
473 extern unsigned short max_session_cb_slots;
474 extern unsigned short send_implementation_id;
475 extern bool recover_lost_locks;
476 
477 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
478 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
479 
480 /* nfs4sysctl.c */
481 #ifdef CONFIG_SYSCTL
482 int nfs4_register_sysctl(void);
483 void nfs4_unregister_sysctl(void);
484 #else
485 static inline int nfs4_register_sysctl(void)
486 {
487 	return 0;
488 }
489 
490 static inline void nfs4_unregister_sysctl(void)
491 {
492 }
493 #endif
494 
495 /* nfs4xdr.c */
496 extern struct rpc_procinfo nfs4_procedures[];
497 
498 struct nfs4_mount_data;
499 
500 /* callback_xdr.c */
501 extern struct svc_version nfs4_callback_version1;
502 extern struct svc_version nfs4_callback_version4;
503 
504 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
505 {
506 	memcpy(dst->data, src->data, sizeof(dst->data));
507 	dst->type = src->type;
508 }
509 
510 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
511 {
512 	if (dst->type != src->type)
513 		return false;
514 	return memcmp(dst->data, src->data, sizeof(dst->data)) == 0;
515 }
516 
517 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
518 {
519 	return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
520 }
521 
522 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
523 {
524 	return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
525 }
526 
527 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
528 {
529 	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
530 }
531 
532 static inline bool nfs4_state_match_open_stateid_other(const struct nfs4_state *state,
533 		const nfs4_stateid *stateid)
534 {
535 	return test_bit(NFS_OPEN_STATE, &state->flags) &&
536 		nfs4_stateid_match_other(&state->open_stateid, stateid);
537 }
538 
539 #else
540 
541 #define nfs4_close_state(a, b) do { } while (0)
542 #define nfs4_close_sync(a, b) do { } while (0)
543 #define nfs4_state_protect(a, b, c, d) do { } while (0)
544 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
545 
546 #endif /* CONFIG_NFS_V4 */
547 #endif /* __LINUX_FS_NFS_NFS4_FS.H */
548