xref: /openbmc/linux/fs/nfs/nfs4_fs.h (revision f125e2d4)
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 	NFS_CLNT_DST_SSC_COPY_STATE,    /* dst server open state on client*/
170 	NFS_CLNT_SRC_SSC_COPY_STATE,    /* src server open state on client*/
171 	NFS_SRV_SSC_COPY_STATE,		/* ssc state on the dst server */
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 	bool interruptible;
210 };
211 
212 struct nfs4_state_recovery_ops {
213 	int owner_flag_bit;
214 	int state_flag_bit;
215 	int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
216 	int (*recover_lock)(struct nfs4_state *, struct file_lock *);
217 	int (*establish_clid)(struct nfs_client *, const struct cred *);
218 	int (*reclaim_complete)(struct nfs_client *, const struct cred *);
219 	int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
220 		const struct cred *);
221 };
222 
223 struct nfs4_opendata {
224 	struct kref kref;
225 	struct nfs_openargs o_arg;
226 	struct nfs_openres o_res;
227 	struct nfs_open_confirmargs c_arg;
228 	struct nfs_open_confirmres c_res;
229 	struct nfs4_string owner_name;
230 	struct nfs4_string group_name;
231 	struct nfs4_label *a_label;
232 	struct nfs_fattr f_attr;
233 	struct nfs4_label *f_label;
234 	struct dentry *dir;
235 	struct dentry *dentry;
236 	struct nfs4_state_owner *owner;
237 	struct nfs4_state *state;
238 	struct iattr attrs;
239 	struct nfs4_layoutget *lgp;
240 	unsigned long timestamp;
241 	bool rpc_done;
242 	bool file_created;
243 	bool is_recover;
244 	bool cancelled;
245 	int rpc_status;
246 };
247 
248 struct nfs4_add_xprt_data {
249 	struct nfs_client	*clp;
250 	const struct cred	*cred;
251 };
252 
253 struct nfs4_state_maintenance_ops {
254 	int (*sched_state_renewal)(struct nfs_client *, const struct cred *, unsigned);
255 	const struct cred * (*get_state_renewal_cred)(struct nfs_client *);
256 	int (*renew_lease)(struct nfs_client *, const struct cred *);
257 };
258 
259 struct nfs4_mig_recovery_ops {
260 	int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
261 		struct page *, const struct cred *);
262 	int (*fsid_present)(struct inode *, const struct cred *);
263 };
264 
265 extern const struct dentry_operations nfs4_dentry_operations;
266 
267 /* dir.c */
268 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
269 		    unsigned, umode_t);
270 
271 /* fs_context.c */
272 extern struct file_system_type nfs4_fs_type;
273 
274 /* nfs4namespace.c */
275 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
276 					 const struct qstr *);
277 int nfs4_submount(struct fs_context *, struct nfs_server *);
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 *,
306 						    struct dentry *,
307 						    struct nfs_fh *,
308 						    struct nfs_fattr *);
309 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
310 extern const struct xattr_handler *nfs4_xattr_handlers[];
311 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
312 		const struct nfs_open_context *ctx,
313 		const struct nfs_lock_context *l_ctx,
314 		fmode_t fmode);
315 extern int nfs4_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
316 			     struct nfs_fattr *fattr, struct nfs4_label *label,
317 			     struct inode *inode);
318 extern int update_open_stateid(struct nfs4_state *state,
319 				const nfs4_stateid *open_stateid,
320 				const nfs4_stateid *deleg_stateid,
321 				fmode_t fmode);
322 
323 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
324 		struct nfs_fsinfo *fsinfo);
325 #if defined(CONFIG_NFS_V4_1)
326 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
327 extern int nfs4_proc_create_session(struct nfs_client *, const struct cred *);
328 extern int nfs4_proc_destroy_session(struct nfs4_session *, const struct cred *);
329 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
330 				  bool sync);
331 extern int nfs4_detect_session_trunking(struct nfs_client *clp,
332 		struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
333 
334 static inline bool
335 is_ds_only_client(struct nfs_client *clp)
336 {
337 	return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
338 		EXCHGID4_FLAG_USE_PNFS_DS;
339 }
340 
341 static inline bool
342 is_ds_client(struct nfs_client *clp)
343 {
344 	return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
345 }
346 
347 static inline bool
348 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
349 		    struct rpc_clnt **clntp, struct rpc_message *msg)
350 {
351 	rpc_authflavor_t flavor;
352 
353 	if (sp4_mode == NFS_SP4_MACH_CRED_CLEANUP ||
354 	    sp4_mode == NFS_SP4_MACH_CRED_PNFS_CLEANUP) {
355 		/* Using machine creds for cleanup operations
356 		 * is only relevent if the client credentials
357 		 * might expire. So don't bother for
358 		 * RPC_AUTH_UNIX.  If file was only exported to
359 		 * sec=sys, the PUTFH would fail anyway.
360 		 */
361 		if ((*clntp)->cl_auth->au_flavor == RPC_AUTH_UNIX)
362 			return false;
363 	}
364 	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
365 		msg->rpc_cred = rpc_machine_cred();
366 
367 		flavor = clp->cl_rpcclient->cl_auth->au_flavor;
368 		WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
369 			     flavor != RPC_AUTH_GSS_KRB5P);
370 		*clntp = clp->cl_rpcclient;
371 
372 		return true;
373 	}
374 	return false;
375 }
376 
377 /*
378  * Function responsible for determining if an rpc_message should use the
379  * machine cred under SP4_MACH_CRED and if so switching the credential and
380  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
381  * Should be called before rpc_call_sync/rpc_call_async.
382  */
383 static inline void
384 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
385 		   struct rpc_clnt **clntp, struct rpc_message *msg)
386 {
387 	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
388 }
389 
390 /*
391  * Special wrapper to nfs4_state_protect for write.
392  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
393  * that use machine cred use NFS_FILE_SYNC.
394  */
395 static inline void
396 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
397 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
398 {
399 	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
400 	    !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
401 		hdr->args.stable = NFS_FILE_SYNC;
402 }
403 #else /* CONFIG_NFS_v4_1 */
404 static inline bool
405 is_ds_only_client(struct nfs_client *clp)
406 {
407 	return false;
408 }
409 
410 static inline bool
411 is_ds_client(struct nfs_client *clp)
412 {
413 	return false;
414 }
415 
416 static inline void
417 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
418 		   struct rpc_clnt **clntp, struct rpc_message *msg)
419 {
420 }
421 
422 static inline void
423 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
424 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
425 {
426 }
427 #endif /* CONFIG_NFS_V4_1 */
428 
429 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
430 
431 extern const u32 nfs4_fattr_bitmap[3];
432 extern const u32 nfs4_statfs_bitmap[3];
433 extern const u32 nfs4_pathconf_bitmap[3];
434 extern const u32 nfs4_fsinfo_bitmap[3];
435 extern const u32 nfs4_fs_locations_bitmap[3];
436 
437 void nfs40_shutdown_client(struct nfs_client *);
438 void nfs41_shutdown_client(struct nfs_client *);
439 int nfs40_init_client(struct nfs_client *);
440 int nfs41_init_client(struct nfs_client *);
441 void nfs4_free_client(struct nfs_client *);
442 
443 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
444 
445 /* nfs4renewd.c */
446 extern void nfs4_schedule_state_renewal(struct nfs_client *);
447 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
448 extern void nfs4_kill_renewd(struct nfs_client *);
449 extern void nfs4_renew_state(struct work_struct *);
450 extern void nfs4_set_lease_period(struct nfs_client *clp, unsigned long lease);
451 
452 
453 /* nfs4state.c */
454 extern const nfs4_stateid current_stateid;
455 
456 const struct cred *nfs4_get_clid_cred(struct nfs_client *clp);
457 const struct cred *nfs4_get_machine_cred(struct nfs_client *clp);
458 const struct cred *nfs4_get_renew_cred(struct nfs_client *clp);
459 int nfs4_discover_server_trunking(struct nfs_client *clp,
460 			struct nfs_client **);
461 int nfs40_discover_server_trunking(struct nfs_client *clp,
462 			struct nfs_client **, const struct cred *);
463 #if defined(CONFIG_NFS_V4_1)
464 int nfs41_discover_server_trunking(struct nfs_client *clp,
465 			struct nfs_client **, const struct cred *);
466 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
467 extern void nfs41_notify_server(struct nfs_client *);
468 bool nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
469 			struct nfs41_server_owner *o2);
470 #else
471 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
472 {
473 }
474 #endif /* CONFIG_NFS_V4_1 */
475 
476 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, const struct cred *, gfp_t);
477 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
478 extern void nfs4_purge_state_owners(struct nfs_server *, struct list_head *);
479 extern void nfs4_free_state_owners(struct list_head *head);
480 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
481 extern void nfs4_put_open_state(struct nfs4_state *);
482 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
483 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
484 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
485 extern void nfs_inode_find_state_and_recover(struct inode *inode,
486 		const nfs4_stateid *stateid);
487 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
488 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
489 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
490 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
491 extern void nfs4_schedule_state_manager(struct nfs_client *);
492 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
493 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
494 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
495 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
496 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
497 extern void nfs41_handle_server_scope(struct nfs_client *,
498 				      struct nfs41_server_scope **);
499 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
500 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
501 extern int nfs4_select_rw_stateid(struct nfs4_state *, fmode_t,
502 		const struct nfs_lock_context *, nfs4_stateid *,
503 		const struct cred **);
504 extern bool nfs4_copy_open_stateid(nfs4_stateid *dst,
505 		struct nfs4_state *state);
506 
507 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
508 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
509 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
510 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
511 extern void nfs_release_seqid(struct nfs_seqid *seqid);
512 extern void nfs_free_seqid(struct nfs_seqid *seqid);
513 extern int nfs4_setup_sequence(struct nfs_client *client,
514 				struct nfs4_sequence_args *args,
515 				struct nfs4_sequence_res *res,
516 				struct rpc_task *task);
517 extern int nfs4_sequence_done(struct rpc_task *task,
518 			      struct nfs4_sequence_res *res);
519 
520 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
521 extern int nfs4_proc_commit(struct file *dst, __u64 offset, __u32 count, struct nfs_commitres *res);
522 extern const nfs4_stateid zero_stateid;
523 extern const nfs4_stateid invalid_stateid;
524 
525 /* nfs4super.c */
526 struct nfs_mount_info;
527 extern struct nfs_subversion nfs_v4;
528 extern bool nfs4_disable_idmapping;
529 extern unsigned short max_session_slots;
530 extern unsigned short max_session_cb_slots;
531 extern unsigned short send_implementation_id;
532 extern bool recover_lost_locks;
533 
534 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
535 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
536 
537 extern int nfs4_try_get_tree(struct fs_context *);
538 extern int nfs4_get_referral_tree(struct fs_context *);
539 
540 /* nfs4sysctl.c */
541 #ifdef CONFIG_SYSCTL
542 int nfs4_register_sysctl(void);
543 void nfs4_unregister_sysctl(void);
544 #else
545 static inline int nfs4_register_sysctl(void)
546 {
547 	return 0;
548 }
549 
550 static inline void nfs4_unregister_sysctl(void)
551 {
552 }
553 #endif
554 
555 /* nfs4xdr.c */
556 extern const struct rpc_procinfo nfs4_procedures[];
557 
558 struct nfs4_mount_data;
559 
560 /* callback_xdr.c */
561 extern const struct svc_version nfs4_callback_version1;
562 extern const struct svc_version nfs4_callback_version4;
563 
564 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
565 {
566 	memcpy(dst->data, src->data, sizeof(dst->data));
567 	dst->type = src->type;
568 }
569 
570 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
571 {
572 	if (dst->type != src->type)
573 		return false;
574 	return memcmp(dst->data, src->data, sizeof(dst->data)) == 0;
575 }
576 
577 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
578 {
579 	return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
580 }
581 
582 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
583 {
584 	return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
585 }
586 
587 static inline bool nfs4_stateid_match_or_older(const nfs4_stateid *dst, const nfs4_stateid *src)
588 {
589 	return nfs4_stateid_match_other(dst, src) &&
590 		!(src->seqid && nfs4_stateid_is_newer(dst, src));
591 }
592 
593 static inline void nfs4_stateid_seqid_inc(nfs4_stateid *s1)
594 {
595 	u32 seqid = be32_to_cpu(s1->seqid);
596 
597 	if (++seqid == 0)
598 		++seqid;
599 	s1->seqid = cpu_to_be32(seqid);
600 }
601 
602 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
603 {
604 	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
605 }
606 
607 static inline bool nfs4_state_match_open_stateid_other(const struct nfs4_state *state,
608 		const nfs4_stateid *stateid)
609 {
610 	return test_bit(NFS_OPEN_STATE, &state->flags) &&
611 		nfs4_stateid_match_other(&state->open_stateid, stateid);
612 }
613 
614 #else
615 
616 #define nfs4_close_state(a, b) do { } while (0)
617 #define nfs4_close_sync(a, b) do { } while (0)
618 #define nfs4_state_protect(a, b, c, d) do { } while (0)
619 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
620 
621 #endif /* CONFIG_NFS_V4 */
622 #endif /* __LINUX_FS_NFS_NFS4_FS.H */
623