xref: /openbmc/linux/fs/nfs/nfs4_fs.h (revision be709d48)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * linux/fs/nfs/nfs4_fs.h
4  *
5  * Copyright (C) 2005 Trond Myklebust
6  *
7  * NFSv4-specific filesystem definitions and declarations
8  */
9 
10 #ifndef __LINUX_FS_NFS_NFS4_FS_H
11 #define __LINUX_FS_NFS_NFS4_FS_H
12 
13 #if defined(CONFIG_NFS_V4_2)
14 #define NFS4_MAX_MINOR_VERSION 2
15 #elif defined(CONFIG_NFS_V4_1)
16 #define NFS4_MAX_MINOR_VERSION 1
17 #else
18 #define NFS4_MAX_MINOR_VERSION 0
19 #endif
20 
21 #if IS_ENABLED(CONFIG_NFS_V4)
22 
23 #define NFS4_MAX_LOOP_ON_RECOVER (10)
24 
25 #include <linux/seqlock.h>
26 
27 struct idmap;
28 
29 enum nfs4_client_state {
30 	NFS4CLNT_MANAGER_RUNNING  = 0,
31 	NFS4CLNT_CHECK_LEASE,
32 	NFS4CLNT_LEASE_EXPIRED,
33 	NFS4CLNT_RECLAIM_REBOOT,
34 	NFS4CLNT_RECLAIM_NOGRACE,
35 	NFS4CLNT_DELEGRETURN,
36 	NFS4CLNT_SESSION_RESET,
37 	NFS4CLNT_LEASE_CONFIRM,
38 	NFS4CLNT_SERVER_SCOPE_MISMATCH,
39 	NFS4CLNT_PURGE_STATE,
40 	NFS4CLNT_BIND_CONN_TO_SESSION,
41 	NFS4CLNT_MOVED,
42 	NFS4CLNT_LEASE_MOVED,
43 	NFS4CLNT_DELEGATION_EXPIRED,
44 	NFS4CLNT_RUN_MANAGER,
45 	NFS4CLNT_DELEGRETURN_RUNNING,
46 };
47 
48 #define NFS4_RENEW_TIMEOUT		0x01
49 #define NFS4_RENEW_DELEGATION_CB	0x02
50 
51 struct nfs_seqid_counter;
52 struct nfs4_minor_version_ops {
53 	u32	minor_version;
54 	unsigned init_caps;
55 
56 	int	(*init_client)(struct nfs_client *);
57 	void	(*shutdown_client)(struct nfs_client *);
58 	bool	(*match_stateid)(const nfs4_stateid *,
59 			const nfs4_stateid *);
60 	int	(*find_root_sec)(struct nfs_server *, struct nfs_fh *,
61 			struct nfs_fsinfo *);
62 	void	(*free_lock_state)(struct nfs_server *,
63 			struct nfs4_lock_state *);
64 	int	(*test_and_free_expired)(struct nfs_server *,
65 			nfs4_stateid *, const struct cred *);
66 	struct nfs_seqid *
67 		(*alloc_seqid)(struct nfs_seqid_counter *, gfp_t);
68 	void	(*session_trunk)(struct rpc_clnt *clnt,
69 			struct rpc_xprt *xprt, void *data);
70 	const struct rpc_call_ops *call_sync_ops;
71 	const struct nfs4_state_recovery_ops *reboot_recovery_ops;
72 	const struct nfs4_state_recovery_ops *nograce_recovery_ops;
73 	const struct nfs4_state_maintenance_ops *state_renewal_ops;
74 	const struct nfs4_mig_recovery_ops *mig_recovery_ops;
75 };
76 
77 #define NFS_SEQID_CONFIRMED 1
78 struct nfs_seqid_counter {
79 	ktime_t create_time;
80 	int owner_id;
81 	int flags;
82 	u32 counter;
83 	spinlock_t lock;		/* Protects the list */
84 	struct list_head list;		/* Defines sequence of RPC calls */
85 	struct rpc_wait_queue	wait;	/* RPC call delay queue */
86 };
87 
88 struct nfs_seqid {
89 	struct nfs_seqid_counter *sequence;
90 	struct list_head list;
91 	struct rpc_task *task;
92 };
93 
94 static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
95 {
96 	if (seqid_mutating_err(-status))
97 		seqid->flags |= NFS_SEQID_CONFIRMED;
98 }
99 
100 /*
101  * NFS4 state_owners and lock_owners are simply labels for ordered
102  * sequences of RPC calls. Their sole purpose is to provide once-only
103  * semantics by allowing the server to identify replayed requests.
104  */
105 struct nfs4_state_owner {
106 	struct nfs_server    *so_server;
107 	struct list_head     so_lru;
108 	unsigned long        so_expires;
109 	struct rb_node	     so_server_node;
110 
111 	const struct cred    *so_cred;	 /* Associated cred */
112 
113 	spinlock_t	     so_lock;
114 	atomic_t	     so_count;
115 	unsigned long	     so_flags;
116 	struct list_head     so_states;
117 	struct nfs_seqid_counter so_seqid;
118 	seqcount_t	     so_reclaim_seqcount;
119 	struct mutex	     so_delegreturn_mutex;
120 };
121 
122 enum {
123 	NFS_OWNER_RECLAIM_REBOOT,
124 	NFS_OWNER_RECLAIM_NOGRACE
125 };
126 
127 #define NFS_LOCK_NEW		0
128 #define NFS_LOCK_RECLAIM	1
129 #define NFS_LOCK_EXPIRED	2
130 
131 /*
132  * struct nfs4_state maintains the client-side state for a given
133  * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
134  *
135  * OPEN:
136  * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
137  * we need to know how many files are open for reading or writing on a
138  * given inode. This information too is stored here.
139  *
140  * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
141  */
142 
143 struct nfs4_lock_state {
144 	struct list_head	ls_locks;	/* Other lock stateids */
145 	struct nfs4_state *	ls_state;	/* Pointer to open state */
146 #define NFS_LOCK_INITIALIZED 0
147 #define NFS_LOCK_LOST        1
148 	unsigned long		ls_flags;
149 	struct nfs_seqid_counter	ls_seqid;
150 	nfs4_stateid		ls_stateid;
151 	refcount_t		ls_count;
152 	fl_owner_t		ls_owner;
153 };
154 
155 /* bits for nfs4_state->flags */
156 enum {
157 	LK_STATE_IN_USE,
158 	NFS_DELEGATED_STATE,		/* Current stateid is delegation */
159 	NFS_OPEN_STATE,			/* OPEN stateid is set */
160 	NFS_O_RDONLY_STATE,		/* OPEN stateid has read-only state */
161 	NFS_O_WRONLY_STATE,		/* OPEN stateid has write-only state */
162 	NFS_O_RDWR_STATE,		/* OPEN stateid has read/write state */
163 	NFS_STATE_RECLAIM_REBOOT,	/* OPEN stateid server rebooted */
164 	NFS_STATE_RECLAIM_NOGRACE,	/* OPEN stateid needs to recover state */
165 	NFS_STATE_POSIX_LOCKS,		/* Posix locks are supported */
166 	NFS_STATE_RECOVERY_FAILED,	/* OPEN stateid state recovery failed */
167 	NFS_STATE_MAY_NOTIFY_LOCK,	/* server may CB_NOTIFY_LOCK */
168 	NFS_STATE_CHANGE_WAIT,		/* A state changing operation is outstanding */
169 #ifdef CONFIG_NFS_V4_2
170 	NFS_CLNT_DST_SSC_COPY_STATE,    /* dst server open state on client*/
171 #endif /* CONFIG_NFS_V4_2 */
172 };
173 
174 struct nfs4_state {
175 	struct list_head open_states;	/* List of states for the same state_owner */
176 	struct list_head inode_states;	/* List of states for the same inode */
177 	struct list_head lock_states;	/* List of subservient lock stateids */
178 
179 	struct nfs4_state_owner *owner;	/* Pointer to the open owner */
180 	struct inode *inode;		/* Pointer to the inode */
181 
182 	unsigned long flags;		/* Do we hold any locks? */
183 	spinlock_t state_lock;		/* Protects the lock_states list */
184 
185 	seqlock_t seqlock;		/* Protects the stateid/open_stateid */
186 	nfs4_stateid stateid;		/* Current stateid: may be delegation */
187 	nfs4_stateid open_stateid;	/* OPEN stateid */
188 
189 	/* The following 3 fields are protected by owner->so_lock */
190 	unsigned int n_rdonly;		/* Number of read-only references */
191 	unsigned int n_wronly;		/* Number of write-only references */
192 	unsigned int n_rdwr;		/* Number of read/write references */
193 	fmode_t state;			/* State on the server (R,W, or RW) */
194 	refcount_t count;
195 
196 	wait_queue_head_t waitq;
197 	struct rcu_head rcu_head;
198 };
199 
200 
201 struct nfs4_exception {
202 	struct nfs4_state *state;
203 	struct inode *inode;
204 	nfs4_stateid *stateid;
205 	long timeout;
206 	unsigned char delay : 1,
207 		      recovering : 1,
208 		      retry : 1;
209 };
210 
211 struct nfs4_state_recovery_ops {
212 	int owner_flag_bit;
213 	int state_flag_bit;
214 	int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
215 	int (*recover_lock)(struct nfs4_state *, struct file_lock *);
216 	int (*establish_clid)(struct nfs_client *, const struct cred *);
217 	int (*reclaim_complete)(struct nfs_client *, const struct cred *);
218 	int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
219 		const struct cred *);
220 };
221 
222 struct nfs4_opendata {
223 	struct kref kref;
224 	struct nfs_openargs o_arg;
225 	struct nfs_openres o_res;
226 	struct nfs_open_confirmargs c_arg;
227 	struct nfs_open_confirmres c_res;
228 	struct nfs4_string owner_name;
229 	struct nfs4_string group_name;
230 	struct nfs4_label *a_label;
231 	struct nfs_fattr f_attr;
232 	struct nfs4_label *f_label;
233 	struct dentry *dir;
234 	struct dentry *dentry;
235 	struct nfs4_state_owner *owner;
236 	struct nfs4_state *state;
237 	struct iattr attrs;
238 	struct nfs4_layoutget *lgp;
239 	unsigned long timestamp;
240 	bool rpc_done;
241 	bool file_created;
242 	bool is_recover;
243 	bool cancelled;
244 	int rpc_status;
245 };
246 
247 struct nfs4_add_xprt_data {
248 	struct nfs_client	*clp;
249 	const struct cred	*cred;
250 };
251 
252 struct nfs4_state_maintenance_ops {
253 	int (*sched_state_renewal)(struct nfs_client *, const struct cred *, unsigned);
254 	const struct cred * (*get_state_renewal_cred)(struct nfs_client *);
255 	int (*renew_lease)(struct nfs_client *, const struct cred *);
256 };
257 
258 struct nfs4_mig_recovery_ops {
259 	int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
260 		struct page *, const struct cred *);
261 	int (*fsid_present)(struct inode *, const struct cred *);
262 };
263 
264 extern const struct dentry_operations nfs4_dentry_operations;
265 
266 /* dir.c */
267 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
268 		    unsigned, umode_t);
269 
270 /* super.c */
271 extern struct file_system_type nfs4_fs_type;
272 
273 /* nfs4namespace.c */
274 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
275 					 const struct qstr *);
276 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
277 			       struct nfs_fh *, struct nfs_fattr *);
278 int nfs4_replace_transport(struct nfs_server *server,
279 				const struct nfs4_fs_locations *locations);
280 
281 /* nfs4proc.c */
282 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
283 extern int nfs4_async_handle_error(struct rpc_task *task,
284 				   struct nfs_server *server,
285 				   struct nfs4_state *state, long *timeout);
286 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
287 			  struct rpc_message *, struct nfs4_sequence_args *,
288 			  struct nfs4_sequence_res *, int);
289 extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int, int);
290 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, const struct cred *, struct nfs4_setclientid_res *);
291 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, const struct cred *);
292 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
293 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, const struct cred *cred);
294 extern int nfs4_proc_exchange_id(struct nfs_client *clp, const struct cred *cred);
295 extern int nfs4_destroy_clientid(struct nfs_client *clp);
296 extern int nfs4_init_clientid(struct nfs_client *, const struct cred *);
297 extern int nfs41_init_clientid(struct nfs_client *, const struct cred *);
298 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
299 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
300 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
301 				  struct nfs4_fs_locations *, struct page *);
302 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
303 		struct page *page, const struct cred *);
304 extern int nfs4_proc_fsid_present(struct inode *, const struct cred *);
305 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, const struct qstr *,
306 			    struct nfs_fh *, struct nfs_fattr *);
307 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
308 extern const struct xattr_handler *nfs4_xattr_handlers[];
309 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
310 		const struct nfs_open_context *ctx,
311 		const struct nfs_lock_context *l_ctx,
312 		fmode_t fmode);
313 
314 #if defined(CONFIG_NFS_V4_1)
315 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
316 extern int nfs4_proc_create_session(struct nfs_client *, const struct cred *);
317 extern int nfs4_proc_destroy_session(struct nfs4_session *, const struct cred *);
318 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
319 		struct nfs_fsinfo *fsinfo);
320 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
321 				  bool sync);
322 extern int nfs4_detect_session_trunking(struct nfs_client *clp,
323 		struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
324 
325 static inline bool
326 is_ds_only_client(struct nfs_client *clp)
327 {
328 	return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
329 		EXCHGID4_FLAG_USE_PNFS_DS;
330 }
331 
332 static inline bool
333 is_ds_client(struct nfs_client *clp)
334 {
335 	return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
336 }
337 
338 static inline bool
339 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
340 		    struct rpc_clnt **clntp, struct rpc_message *msg)
341 {
342 	rpc_authflavor_t flavor;
343 
344 	if (sp4_mode == NFS_SP4_MACH_CRED_CLEANUP ||
345 	    sp4_mode == NFS_SP4_MACH_CRED_PNFS_CLEANUP) {
346 		/* Using machine creds for cleanup operations
347 		 * is only relevent if the client credentials
348 		 * might expire. So don't bother for
349 		 * RPC_AUTH_UNIX.  If file was only exported to
350 		 * sec=sys, the PUTFH would fail anyway.
351 		 */
352 		if ((*clntp)->cl_auth->au_flavor == RPC_AUTH_UNIX)
353 			return false;
354 	}
355 	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
356 		msg->rpc_cred = rpc_machine_cred();
357 
358 		flavor = clp->cl_rpcclient->cl_auth->au_flavor;
359 		WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
360 			     flavor != RPC_AUTH_GSS_KRB5P);
361 		*clntp = clp->cl_rpcclient;
362 
363 		return true;
364 	}
365 	return false;
366 }
367 
368 /*
369  * Function responsible for determining if an rpc_message should use the
370  * machine cred under SP4_MACH_CRED and if so switching the credential and
371  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
372  * Should be called before rpc_call_sync/rpc_call_async.
373  */
374 static inline void
375 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
376 		   struct rpc_clnt **clntp, struct rpc_message *msg)
377 {
378 	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
379 }
380 
381 /*
382  * Special wrapper to nfs4_state_protect for write.
383  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
384  * that use machine cred use NFS_FILE_SYNC.
385  */
386 static inline void
387 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
388 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
389 {
390 	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
391 	    !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
392 		hdr->args.stable = NFS_FILE_SYNC;
393 }
394 #else /* CONFIG_NFS_v4_1 */
395 static inline bool
396 is_ds_only_client(struct nfs_client *clp)
397 {
398 	return false;
399 }
400 
401 static inline bool
402 is_ds_client(struct nfs_client *clp)
403 {
404 	return false;
405 }
406 
407 static inline void
408 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
409 		   struct rpc_clnt **clntp, struct rpc_message *msg)
410 {
411 }
412 
413 static inline void
414 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
415 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
416 {
417 }
418 #endif /* CONFIG_NFS_V4_1 */
419 
420 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
421 
422 extern const u32 nfs4_fattr_bitmap[3];
423 extern const u32 nfs4_statfs_bitmap[3];
424 extern const u32 nfs4_pathconf_bitmap[3];
425 extern const u32 nfs4_fsinfo_bitmap[3];
426 extern const u32 nfs4_fs_locations_bitmap[3];
427 
428 void nfs40_shutdown_client(struct nfs_client *);
429 void nfs41_shutdown_client(struct nfs_client *);
430 int nfs40_init_client(struct nfs_client *);
431 int nfs41_init_client(struct nfs_client *);
432 void nfs4_free_client(struct nfs_client *);
433 
434 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
435 
436 /* nfs4renewd.c */
437 extern void nfs4_schedule_state_renewal(struct nfs_client *);
438 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
439 extern void nfs4_kill_renewd(struct nfs_client *);
440 extern void nfs4_renew_state(struct work_struct *);
441 extern void nfs4_set_lease_period(struct nfs_client *clp,
442 		unsigned long lease,
443 		unsigned long lastrenewed);
444 
445 
446 /* nfs4state.c */
447 const struct cred *nfs4_get_clid_cred(struct nfs_client *clp);
448 const struct cred *nfs4_get_machine_cred(struct nfs_client *clp);
449 const struct cred *nfs4_get_renew_cred(struct nfs_client *clp);
450 int nfs4_discover_server_trunking(struct nfs_client *clp,
451 			struct nfs_client **);
452 int nfs40_discover_server_trunking(struct nfs_client *clp,
453 			struct nfs_client **, const struct cred *);
454 #if defined(CONFIG_NFS_V4_1)
455 int nfs41_discover_server_trunking(struct nfs_client *clp,
456 			struct nfs_client **, const struct cred *);
457 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
458 extern void nfs41_notify_server(struct nfs_client *);
459 #else
460 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
461 {
462 }
463 #endif /* CONFIG_NFS_V4_1 */
464 
465 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, const struct cred *, gfp_t);
466 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
467 extern void nfs4_purge_state_owners(struct nfs_server *);
468 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
469 extern void nfs4_put_open_state(struct nfs4_state *);
470 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
471 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
472 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
473 extern void nfs_inode_find_state_and_recover(struct inode *inode,
474 		const nfs4_stateid *stateid);
475 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
476 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
477 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
478 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
479 extern void nfs4_schedule_state_manager(struct nfs_client *);
480 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
481 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
482 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
483 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
484 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
485 extern void nfs41_handle_server_scope(struct nfs_client *,
486 				      struct nfs41_server_scope **);
487 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
488 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
489 extern int nfs4_select_rw_stateid(struct nfs4_state *, fmode_t,
490 		const struct nfs_lock_context *, nfs4_stateid *,
491 		const struct cred **);
492 extern bool nfs4_refresh_open_stateid(nfs4_stateid *dst,
493 		struct nfs4_state *state);
494 extern bool nfs4_copy_open_stateid(nfs4_stateid *dst,
495 		struct nfs4_state *state);
496 
497 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
498 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
499 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
500 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
501 extern void nfs_release_seqid(struct nfs_seqid *seqid);
502 extern void nfs_free_seqid(struct nfs_seqid *seqid);
503 extern int nfs4_setup_sequence(struct nfs_client *client,
504 				struct nfs4_sequence_args *args,
505 				struct nfs4_sequence_res *res,
506 				struct rpc_task *task);
507 extern int nfs4_sequence_done(struct rpc_task *task,
508 			      struct nfs4_sequence_res *res);
509 
510 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
511 extern int nfs4_proc_commit(struct file *dst, __u64 offset, __u32 count, struct nfs_commitres *res);
512 extern const nfs4_stateid zero_stateid;
513 extern const nfs4_stateid invalid_stateid;
514 
515 /* nfs4super.c */
516 struct nfs_mount_info;
517 extern struct nfs_subversion nfs_v4;
518 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
519 extern bool nfs4_disable_idmapping;
520 extern unsigned short max_session_slots;
521 extern unsigned short max_session_cb_slots;
522 extern unsigned short send_implementation_id;
523 extern bool recover_lost_locks;
524 
525 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
526 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
527 
528 /* nfs4sysctl.c */
529 #ifdef CONFIG_SYSCTL
530 int nfs4_register_sysctl(void);
531 void nfs4_unregister_sysctl(void);
532 #else
533 static inline int nfs4_register_sysctl(void)
534 {
535 	return 0;
536 }
537 
538 static inline void nfs4_unregister_sysctl(void)
539 {
540 }
541 #endif
542 
543 /* nfs4xdr.c */
544 extern const struct rpc_procinfo nfs4_procedures[];
545 
546 struct nfs4_mount_data;
547 
548 /* callback_xdr.c */
549 extern const struct svc_version nfs4_callback_version1;
550 extern const struct svc_version nfs4_callback_version4;
551 
552 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
553 {
554 	memcpy(dst->data, src->data, sizeof(dst->data));
555 	dst->type = src->type;
556 }
557 
558 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
559 {
560 	if (dst->type != src->type)
561 		return false;
562 	return memcmp(dst->data, src->data, sizeof(dst->data)) == 0;
563 }
564 
565 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
566 {
567 	return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
568 }
569 
570 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
571 {
572 	return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
573 }
574 
575 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
576 {
577 	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
578 }
579 
580 static inline bool nfs4_state_match_open_stateid_other(const struct nfs4_state *state,
581 		const nfs4_stateid *stateid)
582 {
583 	return test_bit(NFS_OPEN_STATE, &state->flags) &&
584 		nfs4_stateid_match_other(&state->open_stateid, stateid);
585 }
586 
587 #else
588 
589 #define nfs4_close_state(a, b) do { } while (0)
590 #define nfs4_close_sync(a, b) do { } while (0)
591 #define nfs4_state_protect(a, b, c, d) do { } while (0)
592 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
593 
594 #endif /* CONFIG_NFS_V4 */
595 #endif /* __LINUX_FS_NFS_NFS4_FS.H */
596