xref: /openbmc/linux/fs/nfs/nfs4_fs.h (revision 132db935)
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_RECALL_RUNNING,
46 	NFS4CLNT_RECALL_ANY_LAYOUT_READ,
47 	NFS4CLNT_RECALL_ANY_LAYOUT_RW,
48 };
49 
50 #define NFS4_RENEW_TIMEOUT		0x01
51 #define NFS4_RENEW_DELEGATION_CB	0x02
52 
53 struct nfs_seqid_counter;
54 struct nfs4_minor_version_ops {
55 	u32	minor_version;
56 	unsigned init_caps;
57 
58 	int	(*init_client)(struct nfs_client *);
59 	void	(*shutdown_client)(struct nfs_client *);
60 	bool	(*match_stateid)(const nfs4_stateid *,
61 			const nfs4_stateid *);
62 	int	(*find_root_sec)(struct nfs_server *, struct nfs_fh *,
63 			struct nfs_fsinfo *);
64 	void	(*free_lock_state)(struct nfs_server *,
65 			struct nfs4_lock_state *);
66 	int	(*test_and_free_expired)(struct nfs_server *,
67 			nfs4_stateid *, const struct cred *);
68 	struct nfs_seqid *
69 		(*alloc_seqid)(struct nfs_seqid_counter *, gfp_t);
70 	void	(*session_trunk)(struct rpc_clnt *clnt,
71 			struct rpc_xprt *xprt, void *data);
72 	const struct rpc_call_ops *call_sync_ops;
73 	const struct nfs4_state_recovery_ops *reboot_recovery_ops;
74 	const struct nfs4_state_recovery_ops *nograce_recovery_ops;
75 	const struct nfs4_state_maintenance_ops *state_renewal_ops;
76 	const struct nfs4_mig_recovery_ops *mig_recovery_ops;
77 };
78 
79 #define NFS_SEQID_CONFIRMED 1
80 struct nfs_seqid_counter {
81 	ktime_t create_time;
82 	int owner_id;
83 	int flags;
84 	u32 counter;
85 	spinlock_t lock;		/* Protects the list */
86 	struct list_head list;		/* Defines sequence of RPC calls */
87 	struct rpc_wait_queue	wait;	/* RPC call delay queue */
88 };
89 
90 struct nfs_seqid {
91 	struct nfs_seqid_counter *sequence;
92 	struct list_head list;
93 	struct rpc_task *task;
94 };
95 
96 static inline void nfs_confirm_seqid(struct nfs_seqid_counter *seqid, int status)
97 {
98 	if (seqid_mutating_err(-status))
99 		seqid->flags |= NFS_SEQID_CONFIRMED;
100 }
101 
102 /*
103  * NFS4 state_owners and lock_owners are simply labels for ordered
104  * sequences of RPC calls. Their sole purpose is to provide once-only
105  * semantics by allowing the server to identify replayed requests.
106  */
107 struct nfs4_state_owner {
108 	struct nfs_server    *so_server;
109 	struct list_head     so_lru;
110 	unsigned long        so_expires;
111 	struct rb_node	     so_server_node;
112 
113 	const struct cred    *so_cred;	 /* Associated cred */
114 
115 	spinlock_t	     so_lock;
116 	atomic_t	     so_count;
117 	unsigned long	     so_flags;
118 	struct list_head     so_states;
119 	struct nfs_seqid_counter so_seqid;
120 	seqcount_t	     so_reclaim_seqcount;
121 	struct mutex	     so_delegreturn_mutex;
122 };
123 
124 enum {
125 	NFS_OWNER_RECLAIM_REBOOT,
126 	NFS_OWNER_RECLAIM_NOGRACE
127 };
128 
129 #define NFS_LOCK_NEW		0
130 #define NFS_LOCK_RECLAIM	1
131 #define NFS_LOCK_EXPIRED	2
132 
133 /*
134  * struct nfs4_state maintains the client-side state for a given
135  * (state_owner,inode) tuple (OPEN) or state_owner (LOCK).
136  *
137  * OPEN:
138  * In order to know when to OPEN_DOWNGRADE or CLOSE the state on the server,
139  * we need to know how many files are open for reading or writing on a
140  * given inode. This information too is stored here.
141  *
142  * LOCK: one nfs4_state (LOCK) to hold the lock stateid nfs4_state(OPEN)
143  */
144 
145 struct nfs4_lock_state {
146 	struct list_head	ls_locks;	/* Other lock stateids */
147 	struct nfs4_state *	ls_state;	/* Pointer to open state */
148 #define NFS_LOCK_INITIALIZED 0
149 #define NFS_LOCK_LOST        1
150 	unsigned long		ls_flags;
151 	struct nfs_seqid_counter	ls_seqid;
152 	nfs4_stateid		ls_stateid;
153 	refcount_t		ls_count;
154 	fl_owner_t		ls_owner;
155 };
156 
157 /* bits for nfs4_state->flags */
158 enum {
159 	LK_STATE_IN_USE,
160 	NFS_DELEGATED_STATE,		/* Current stateid is delegation */
161 	NFS_OPEN_STATE,			/* OPEN stateid is set */
162 	NFS_O_RDONLY_STATE,		/* OPEN stateid has read-only state */
163 	NFS_O_WRONLY_STATE,		/* OPEN stateid has write-only state */
164 	NFS_O_RDWR_STATE,		/* OPEN stateid has read/write state */
165 	NFS_STATE_RECLAIM_REBOOT,	/* OPEN stateid server rebooted */
166 	NFS_STATE_RECLAIM_NOGRACE,	/* OPEN stateid needs to recover state */
167 	NFS_STATE_POSIX_LOCKS,		/* Posix locks are supported */
168 	NFS_STATE_RECOVERY_FAILED,	/* OPEN stateid state recovery failed */
169 	NFS_STATE_MAY_NOTIFY_LOCK,	/* server may CB_NOTIFY_LOCK */
170 	NFS_STATE_CHANGE_WAIT,		/* A state changing operation is outstanding */
171 	NFS_CLNT_DST_SSC_COPY_STATE,    /* dst server open state on client*/
172 	NFS_CLNT_SRC_SSC_COPY_STATE,    /* src server open state on client*/
173 	NFS_SRV_SSC_COPY_STATE,		/* ssc state on the dst server */
174 };
175 
176 struct nfs4_state {
177 	struct list_head open_states;	/* List of states for the same state_owner */
178 	struct list_head inode_states;	/* List of states for the same inode */
179 	struct list_head lock_states;	/* List of subservient lock stateids */
180 
181 	struct nfs4_state_owner *owner;	/* Pointer to the open owner */
182 	struct inode *inode;		/* Pointer to the inode */
183 
184 	unsigned long flags;		/* Do we hold any locks? */
185 	spinlock_t state_lock;		/* Protects the lock_states list */
186 
187 	seqlock_t seqlock;		/* Protects the stateid/open_stateid */
188 	nfs4_stateid stateid;		/* Current stateid: may be delegation */
189 	nfs4_stateid open_stateid;	/* OPEN stateid */
190 
191 	/* The following 3 fields are protected by owner->so_lock */
192 	unsigned int n_rdonly;		/* Number of read-only references */
193 	unsigned int n_wronly;		/* Number of write-only references */
194 	unsigned int n_rdwr;		/* Number of read/write references */
195 	fmode_t state;			/* State on the server (R,W, or RW) */
196 	refcount_t count;
197 
198 	wait_queue_head_t waitq;
199 	struct rcu_head rcu_head;
200 };
201 
202 
203 struct nfs4_exception {
204 	struct nfs4_state *state;
205 	struct inode *inode;
206 	nfs4_stateid *stateid;
207 	long timeout;
208 	unsigned char delay : 1,
209 		      recovering : 1,
210 		      retry : 1;
211 	bool interruptible;
212 };
213 
214 struct nfs4_state_recovery_ops {
215 	int owner_flag_bit;
216 	int state_flag_bit;
217 	int (*recover_open)(struct nfs4_state_owner *, struct nfs4_state *);
218 	int (*recover_lock)(struct nfs4_state *, struct file_lock *);
219 	int (*establish_clid)(struct nfs_client *, const struct cred *);
220 	int (*reclaim_complete)(struct nfs_client *, const struct cred *);
221 	int (*detect_trunking)(struct nfs_client *, struct nfs_client **,
222 		const struct cred *);
223 };
224 
225 struct nfs4_opendata {
226 	struct kref kref;
227 	struct nfs_openargs o_arg;
228 	struct nfs_openres o_res;
229 	struct nfs_open_confirmargs c_arg;
230 	struct nfs_open_confirmres c_res;
231 	struct nfs4_string owner_name;
232 	struct nfs4_string group_name;
233 	struct nfs4_label *a_label;
234 	struct nfs_fattr f_attr;
235 	struct nfs4_label *f_label;
236 	struct dentry *dir;
237 	struct dentry *dentry;
238 	struct nfs4_state_owner *owner;
239 	struct nfs4_state *state;
240 	struct iattr attrs;
241 	struct nfs4_layoutget *lgp;
242 	unsigned long timestamp;
243 	bool rpc_done;
244 	bool file_created;
245 	bool is_recover;
246 	bool cancelled;
247 	int rpc_status;
248 };
249 
250 struct nfs4_add_xprt_data {
251 	struct nfs_client	*clp;
252 	const struct cred	*cred;
253 };
254 
255 struct nfs4_state_maintenance_ops {
256 	int (*sched_state_renewal)(struct nfs_client *, const struct cred *, unsigned);
257 	const struct cred * (*get_state_renewal_cred)(struct nfs_client *);
258 	int (*renew_lease)(struct nfs_client *, const struct cred *);
259 };
260 
261 struct nfs4_mig_recovery_ops {
262 	int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
263 		struct page *, const struct cred *);
264 	int (*fsid_present)(struct inode *, const struct cred *);
265 };
266 
267 extern const struct dentry_operations nfs4_dentry_operations;
268 
269 /* dir.c */
270 int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
271 		    unsigned, umode_t);
272 
273 /* fs_context.c */
274 extern struct file_system_type nfs4_fs_type;
275 
276 /* nfs4namespace.c */
277 struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
278 					 const struct qstr *);
279 int nfs4_submount(struct fs_context *, struct nfs_server *);
280 int nfs4_replace_transport(struct nfs_server *server,
281 				const struct nfs4_fs_locations *locations);
282 
283 /* nfs4proc.c */
284 extern int nfs4_handle_exception(struct nfs_server *, int, struct nfs4_exception *);
285 extern int nfs4_async_handle_error(struct rpc_task *task,
286 				   struct nfs_server *server,
287 				   struct nfs4_state *state, long *timeout);
288 extern int nfs4_call_sync(struct rpc_clnt *, struct nfs_server *,
289 			  struct rpc_message *, struct nfs4_sequence_args *,
290 			  struct nfs4_sequence_res *, int);
291 extern void nfs4_init_sequence(struct nfs4_sequence_args *, struct nfs4_sequence_res *, int, int);
292 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, const struct cred *, struct nfs4_setclientid_res *);
293 extern int nfs4_proc_setclientid_confirm(struct nfs_client *, struct nfs4_setclientid_res *arg, const struct cred *);
294 extern int nfs4_proc_get_rootfh(struct nfs_server *, struct nfs_fh *, struct nfs_fsinfo *, bool);
295 extern int nfs4_proc_bind_conn_to_session(struct nfs_client *, const struct cred *cred);
296 extern int nfs4_proc_exchange_id(struct nfs_client *clp, const struct cred *cred);
297 extern int nfs4_destroy_clientid(struct nfs_client *clp);
298 extern int nfs4_init_clientid(struct nfs_client *, const struct cred *);
299 extern int nfs41_init_clientid(struct nfs_client *, const struct cred *);
300 extern int nfs4_do_close(struct nfs4_state *state, gfp_t gfp_mask, int wait);
301 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
302 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
303 				  struct nfs4_fs_locations *, struct page *);
304 extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
305 		struct page *page, const struct cred *);
306 extern int nfs4_proc_fsid_present(struct inode *, const struct cred *);
307 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *,
308 						    struct dentry *,
309 						    struct nfs_fh *,
310 						    struct nfs_fattr *);
311 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
312 extern const struct xattr_handler *nfs4_xattr_handlers[];
313 extern int nfs4_set_rw_stateid(nfs4_stateid *stateid,
314 		const struct nfs_open_context *ctx,
315 		const struct nfs_lock_context *l_ctx,
316 		fmode_t fmode);
317 extern int nfs4_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
318 			     struct nfs_fattr *fattr, struct nfs4_label *label,
319 			     struct inode *inode);
320 extern int update_open_stateid(struct nfs4_state *state,
321 				const nfs4_stateid *open_stateid,
322 				const nfs4_stateid *deleg_stateid,
323 				fmode_t fmode);
324 
325 extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
326 		struct nfs_fsinfo *fsinfo);
327 #if defined(CONFIG_NFS_V4_1)
328 extern int nfs41_sequence_done(struct rpc_task *, struct nfs4_sequence_res *);
329 extern int nfs4_proc_create_session(struct nfs_client *, const struct cred *);
330 extern int nfs4_proc_destroy_session(struct nfs4_session *, const struct cred *);
331 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
332 				  bool sync);
333 extern int nfs4_detect_session_trunking(struct nfs_client *clp,
334 		struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
335 
336 static inline bool
337 is_ds_only_client(struct nfs_client *clp)
338 {
339 	return (clp->cl_exchange_flags & EXCHGID4_FLAG_MASK_PNFS) ==
340 		EXCHGID4_FLAG_USE_PNFS_DS;
341 }
342 
343 static inline bool
344 is_ds_client(struct nfs_client *clp)
345 {
346 	return clp->cl_exchange_flags & EXCHGID4_FLAG_USE_PNFS_DS;
347 }
348 
349 static inline bool
350 _nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
351 		    struct rpc_clnt **clntp, struct rpc_message *msg)
352 {
353 	rpc_authflavor_t flavor;
354 
355 	if (sp4_mode == NFS_SP4_MACH_CRED_CLEANUP ||
356 	    sp4_mode == NFS_SP4_MACH_CRED_PNFS_CLEANUP) {
357 		/* Using machine creds for cleanup operations
358 		 * is only relevent if the client credentials
359 		 * might expire. So don't bother for
360 		 * RPC_AUTH_UNIX.  If file was only exported to
361 		 * sec=sys, the PUTFH would fail anyway.
362 		 */
363 		if ((*clntp)->cl_auth->au_flavor == RPC_AUTH_UNIX)
364 			return false;
365 	}
366 	if (test_bit(sp4_mode, &clp->cl_sp4_flags)) {
367 		msg->rpc_cred = rpc_machine_cred();
368 
369 		flavor = clp->cl_rpcclient->cl_auth->au_flavor;
370 		WARN_ON_ONCE(flavor != RPC_AUTH_GSS_KRB5I &&
371 			     flavor != RPC_AUTH_GSS_KRB5P);
372 		*clntp = clp->cl_rpcclient;
373 
374 		return true;
375 	}
376 	return false;
377 }
378 
379 /*
380  * Function responsible for determining if an rpc_message should use the
381  * machine cred under SP4_MACH_CRED and if so switching the credential and
382  * authflavor (using the nfs_client's rpc_clnt which will be krb5i/p).
383  * Should be called before rpc_call_sync/rpc_call_async.
384  */
385 static inline void
386 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_mode,
387 		   struct rpc_clnt **clntp, struct rpc_message *msg)
388 {
389 	_nfs4_state_protect(clp, sp4_mode, clntp, msg);
390 }
391 
392 /*
393  * Special wrapper to nfs4_state_protect for write.
394  * If WRITE can use machine cred but COMMIT cannot, make sure all writes
395  * that use machine cred use NFS_FILE_SYNC.
396  */
397 static inline void
398 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
399 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
400 {
401 	if (_nfs4_state_protect(clp, NFS_SP4_MACH_CRED_WRITE, clntp, msg) &&
402 	    !test_bit(NFS_SP4_MACH_CRED_COMMIT, &clp->cl_sp4_flags))
403 		hdr->args.stable = NFS_FILE_SYNC;
404 }
405 #else /* CONFIG_NFS_v4_1 */
406 static inline bool
407 is_ds_only_client(struct nfs_client *clp)
408 {
409 	return false;
410 }
411 
412 static inline bool
413 is_ds_client(struct nfs_client *clp)
414 {
415 	return false;
416 }
417 
418 static inline void
419 nfs4_state_protect(struct nfs_client *clp, unsigned long sp4_flags,
420 		   struct rpc_clnt **clntp, struct rpc_message *msg)
421 {
422 }
423 
424 static inline void
425 nfs4_state_protect_write(struct nfs_client *clp, struct rpc_clnt **clntp,
426 			 struct rpc_message *msg, struct nfs_pgio_header *hdr)
427 {
428 }
429 #endif /* CONFIG_NFS_V4_1 */
430 
431 extern const struct nfs4_minor_version_ops *nfs_v4_minor_ops[];
432 
433 extern const u32 nfs4_fattr_bitmap[3];
434 extern const u32 nfs4_statfs_bitmap[3];
435 extern const u32 nfs4_pathconf_bitmap[3];
436 extern const u32 nfs4_fsinfo_bitmap[3];
437 extern const u32 nfs4_fs_locations_bitmap[3];
438 
439 void nfs40_shutdown_client(struct nfs_client *);
440 void nfs41_shutdown_client(struct nfs_client *);
441 int nfs40_init_client(struct nfs_client *);
442 int nfs41_init_client(struct nfs_client *);
443 void nfs4_free_client(struct nfs_client *);
444 
445 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *);
446 
447 /* nfs4renewd.c */
448 extern void nfs4_schedule_state_renewal(struct nfs_client *);
449 extern void nfs4_renewd_prepare_shutdown(struct nfs_server *);
450 extern void nfs4_kill_renewd(struct nfs_client *);
451 extern void nfs4_renew_state(struct work_struct *);
452 extern void nfs4_set_lease_period(struct nfs_client *clp, unsigned long lease);
453 
454 
455 /* nfs4state.c */
456 extern const nfs4_stateid current_stateid;
457 
458 const struct cred *nfs4_get_clid_cred(struct nfs_client *clp);
459 const struct cred *nfs4_get_machine_cred(struct nfs_client *clp);
460 const struct cred *nfs4_get_renew_cred(struct nfs_client *clp);
461 int nfs4_discover_server_trunking(struct nfs_client *clp,
462 			struct nfs_client **);
463 int nfs40_discover_server_trunking(struct nfs_client *clp,
464 			struct nfs_client **, const struct cred *);
465 #if defined(CONFIG_NFS_V4_1)
466 int nfs41_discover_server_trunking(struct nfs_client *clp,
467 			struct nfs_client **, const struct cred *);
468 extern void nfs4_schedule_session_recovery(struct nfs4_session *, int);
469 extern void nfs41_notify_server(struct nfs_client *);
470 bool nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
471 			struct nfs41_server_owner *o2);
472 #else
473 static inline void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
474 {
475 }
476 #endif /* CONFIG_NFS_V4_1 */
477 
478 extern struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *, const struct cred *, gfp_t);
479 extern void nfs4_put_state_owner(struct nfs4_state_owner *);
480 extern void nfs4_purge_state_owners(struct nfs_server *, struct list_head *);
481 extern void nfs4_free_state_owners(struct list_head *head);
482 extern struct nfs4_state * nfs4_get_open_state(struct inode *, struct nfs4_state_owner *);
483 extern void nfs4_put_open_state(struct nfs4_state *);
484 extern void nfs4_close_state(struct nfs4_state *, fmode_t);
485 extern void nfs4_close_sync(struct nfs4_state *, fmode_t);
486 extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t);
487 extern void nfs_inode_find_state_and_recover(struct inode *inode,
488 		const nfs4_stateid *stateid);
489 extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_state *);
490 extern void nfs4_schedule_lease_recovery(struct nfs_client *);
491 extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
492 extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
493 extern void nfs4_schedule_state_manager(struct nfs_client *);
494 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
495 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
496 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
497 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
498 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
499 extern void nfs41_handle_server_scope(struct nfs_client *,
500 				      struct nfs41_server_scope **);
501 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
502 extern int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl);
503 extern int nfs4_select_rw_stateid(struct nfs4_state *, fmode_t,
504 		const struct nfs_lock_context *, nfs4_stateid *,
505 		const struct cred **);
506 extern bool nfs4_copy_open_stateid(nfs4_stateid *dst,
507 		struct nfs4_state *state);
508 
509 extern struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask);
510 extern int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task);
511 extern void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid);
512 extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid);
513 extern void nfs_release_seqid(struct nfs_seqid *seqid);
514 extern void nfs_free_seqid(struct nfs_seqid *seqid);
515 extern int nfs4_setup_sequence(struct nfs_client *client,
516 				struct nfs4_sequence_args *args,
517 				struct nfs4_sequence_res *res,
518 				struct rpc_task *task);
519 extern int nfs4_sequence_done(struct rpc_task *task,
520 			      struct nfs4_sequence_res *res);
521 
522 extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp);
523 extern int nfs4_proc_commit(struct file *dst, __u64 offset, __u32 count, struct nfs_commitres *res);
524 extern const nfs4_stateid zero_stateid;
525 extern const nfs4_stateid invalid_stateid;
526 
527 /* nfs4super.c */
528 struct nfs_mount_info;
529 extern struct nfs_subversion nfs_v4;
530 extern bool nfs4_disable_idmapping;
531 extern unsigned short max_session_slots;
532 extern unsigned short max_session_cb_slots;
533 extern unsigned short send_implementation_id;
534 extern bool recover_lost_locks;
535 
536 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
537 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
538 
539 extern int nfs4_try_get_tree(struct fs_context *);
540 extern int nfs4_get_referral_tree(struct fs_context *);
541 
542 /* nfs4sysctl.c */
543 #ifdef CONFIG_SYSCTL
544 int nfs4_register_sysctl(void);
545 void nfs4_unregister_sysctl(void);
546 #else
547 static inline int nfs4_register_sysctl(void)
548 {
549 	return 0;
550 }
551 
552 static inline void nfs4_unregister_sysctl(void)
553 {
554 }
555 #endif
556 
557 /* nfs4xdr.c */
558 extern const struct rpc_procinfo nfs4_procedures[];
559 
560 struct nfs4_mount_data;
561 
562 /* callback_xdr.c */
563 extern const struct svc_version nfs4_callback_version1;
564 extern const struct svc_version nfs4_callback_version4;
565 
566 static inline void nfs4_stateid_copy(nfs4_stateid *dst, const nfs4_stateid *src)
567 {
568 	memcpy(dst->data, src->data, sizeof(dst->data));
569 	dst->type = src->type;
570 }
571 
572 static inline bool nfs4_stateid_match(const nfs4_stateid *dst, const nfs4_stateid *src)
573 {
574 	if (dst->type != src->type)
575 		return false;
576 	return memcmp(dst->data, src->data, sizeof(dst->data)) == 0;
577 }
578 
579 static inline bool nfs4_stateid_match_other(const nfs4_stateid *dst, const nfs4_stateid *src)
580 {
581 	return memcmp(dst->other, src->other, NFS4_STATEID_OTHER_SIZE) == 0;
582 }
583 
584 static inline bool nfs4_stateid_is_newer(const nfs4_stateid *s1, const nfs4_stateid *s2)
585 {
586 	return (s32)(be32_to_cpu(s1->seqid) - be32_to_cpu(s2->seqid)) > 0;
587 }
588 
589 static inline bool nfs4_stateid_match_or_older(const nfs4_stateid *dst, const nfs4_stateid *src)
590 {
591 	return nfs4_stateid_match_other(dst, src) &&
592 		!(src->seqid && nfs4_stateid_is_newer(dst, src));
593 }
594 
595 static inline void nfs4_stateid_seqid_inc(nfs4_stateid *s1)
596 {
597 	u32 seqid = be32_to_cpu(s1->seqid);
598 
599 	if (++seqid == 0)
600 		++seqid;
601 	s1->seqid = cpu_to_be32(seqid);
602 }
603 
604 static inline bool nfs4_valid_open_stateid(const struct nfs4_state *state)
605 {
606 	return test_bit(NFS_STATE_RECOVERY_FAILED, &state->flags) == 0;
607 }
608 
609 static inline bool nfs4_state_match_open_stateid_other(const struct nfs4_state *state,
610 		const nfs4_stateid *stateid)
611 {
612 	return test_bit(NFS_OPEN_STATE, &state->flags) &&
613 		nfs4_stateid_match_other(&state->open_stateid, stateid);
614 }
615 
616 #else
617 
618 #define nfs4_close_state(a, b) do { } while (0)
619 #define nfs4_close_sync(a, b) do { } while (0)
620 #define nfs4_state_protect(a, b, c, d) do { } while (0)
621 #define nfs4_state_protect_write(a, b, c, d) do { } while (0)
622 
623 #endif /* CONFIG_NFS_V4 */
624 #endif /* __LINUX_FS_NFS_NFS4_FS.H */
625