xref: /openbmc/linux/fs/nfsd/state.h (revision f5b06569)
1 /*
2  *  Copyright (c) 2001 The Regents of the University of Michigan.
3  *  All rights reserved.
4  *
5  *  Kendrick Smith <kmsmith@umich.edu>
6  *  Andy Adamson <andros@umich.edu>
7  *
8  *  Redistribution and use in source and binary forms, with or without
9  *  modification, are permitted provided that the following conditions
10  *  are met:
11  *
12  *  1. Redistributions of source code must retain the above copyright
13  *     notice, this list of conditions and the following disclaimer.
14  *  2. Redistributions in binary form must reproduce the above copyright
15  *     notice, this list of conditions and the following disclaimer in the
16  *     documentation and/or other materials provided with the distribution.
17  *  3. Neither the name of the University nor the names of its
18  *     contributors may be used to endorse or promote products derived
19  *     from this software without specific prior written permission.
20  *
21  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
22  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
28  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
29  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  */
34 
35 #ifndef _NFSD4_STATE_H
36 #define _NFSD4_STATE_H
37 
38 #include <linux/idr.h>
39 #include <linux/sunrpc/svc_xprt.h>
40 #include "nfsfh.h"
41 
42 typedef struct {
43 	u32             cl_boot;
44 	u32             cl_id;
45 } clientid_t;
46 
47 typedef struct {
48 	clientid_t	so_clid;
49 	u32		so_id;
50 } stateid_opaque_t;
51 
52 typedef struct {
53 	u32                     si_generation;
54 	stateid_opaque_t        si_opaque;
55 } stateid_t;
56 
57 #define STATEID_FMT	"(%08x/%08x/%08x/%08x)"
58 #define STATEID_VAL(s) \
59 	(s)->si_opaque.so_clid.cl_boot, \
60 	(s)->si_opaque.so_clid.cl_id, \
61 	(s)->si_opaque.so_id, \
62 	(s)->si_generation
63 
64 struct nfsd4_callback {
65 	struct nfs4_client *cb_clp;
66 	u32 cb_minorversion;
67 	struct rpc_message cb_msg;
68 	const struct nfsd4_callback_ops *cb_ops;
69 	struct work_struct cb_work;
70 	int cb_seq_status;
71 	int cb_status;
72 	bool cb_need_restart;
73 };
74 
75 struct nfsd4_callback_ops {
76 	void (*prepare)(struct nfsd4_callback *);
77 	int (*done)(struct nfsd4_callback *, struct rpc_task *);
78 	void (*release)(struct nfsd4_callback *);
79 };
80 
81 /*
82  * A core object that represents a "common" stateid. These are generally
83  * embedded within the different (more specific) stateid objects and contain
84  * fields that are of general use to any stateid.
85  */
86 struct nfs4_stid {
87 	atomic_t		sc_count;
88 #define NFS4_OPEN_STID 1
89 #define NFS4_LOCK_STID 2
90 #define NFS4_DELEG_STID 4
91 /* For an open stateid kept around *only* to process close replays: */
92 #define NFS4_CLOSED_STID 8
93 /* For a deleg stateid kept around only to process free_stateid's: */
94 #define NFS4_REVOKED_DELEG_STID 16
95 #define NFS4_CLOSED_DELEG_STID 32
96 #define NFS4_LAYOUT_STID 64
97 	unsigned char		sc_type;
98 	stateid_t		sc_stateid;
99 	spinlock_t		sc_lock;
100 	struct nfs4_client	*sc_client;
101 	struct nfs4_file	*sc_file;
102 	void			(*sc_free)(struct nfs4_stid *);
103 };
104 
105 /*
106  * Represents a delegation stateid. The nfs4_client holds references to these
107  * and they are put when it is being destroyed or when the delegation is
108  * returned by the client:
109  *
110  * o 1 reference as long as a delegation is still in force (taken when it's
111  *   alloc'd, put when it's returned or revoked)
112  *
113  * o 1 reference as long as a recall rpc is in progress (taken when the lease
114  *   is broken, put when the rpc exits)
115  *
116  * o 1 more ephemeral reference for each nfsd thread currently doing something
117  *   with that delegation without holding the cl_lock
118  *
119  * If the server attempts to recall a delegation and the client doesn't do so
120  * before a timeout, the server may also revoke the delegation. In that case,
121  * the object will either be destroyed (v4.0) or moved to a per-client list of
122  * revoked delegations (v4.1+).
123  *
124  * This object is a superset of the nfs4_stid.
125  */
126 struct nfs4_delegation {
127 	struct nfs4_stid	dl_stid; /* must be first field */
128 	struct list_head	dl_perfile;
129 	struct list_head	dl_perclnt;
130 	struct list_head	dl_recall_lru;  /* delegation recalled */
131 	struct nfs4_clnt_odstate *dl_clnt_odstate;
132 	u32			dl_type;
133 	time_t			dl_time;
134 /* For recall: */
135 	int			dl_retries;
136 	struct nfsd4_callback	dl_recall;
137 };
138 
139 #define cb_to_delegation(cb) \
140 	container_of(cb, struct nfs4_delegation, dl_recall)
141 
142 /* client delegation callback info */
143 struct nfs4_cb_conn {
144 	/* SETCLIENTID info */
145 	struct sockaddr_storage	cb_addr;
146 	struct sockaddr_storage	cb_saddr;
147 	size_t			cb_addrlen;
148 	u32                     cb_prog; /* used only in 4.0 case;
149 					    per-session otherwise */
150 	u32                     cb_ident;	/* minorversion 0 only */
151 	struct svc_xprt		*cb_xprt;	/* minorversion 1 only */
152 };
153 
154 static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
155 {
156 	return container_of(s, struct nfs4_delegation, dl_stid);
157 }
158 
159 /* Maximum number of slots per session. 160 is useful for long haul TCP */
160 #define NFSD_MAX_SLOTS_PER_SESSION     160
161 /* Maximum number of operations per session compound */
162 #define NFSD_MAX_OPS_PER_COMPOUND	16
163 /* Maximum  session per slot cache size */
164 #define NFSD_SLOT_CACHE_SIZE		2048
165 /* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
166 #define NFSD_CACHE_SIZE_SLOTS_PER_SESSION	32
167 #define NFSD_MAX_MEM_PER_SESSION  \
168 		(NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
169 
170 struct nfsd4_slot {
171 	u32	sl_seqid;
172 	__be32	sl_status;
173 	u32	sl_datalen;
174 	u16	sl_opcnt;
175 #define NFSD4_SLOT_INUSE	(1 << 0)
176 #define NFSD4_SLOT_CACHETHIS	(1 << 1)
177 #define NFSD4_SLOT_INITIALIZED	(1 << 2)
178 	u8	sl_flags;
179 	char	sl_data[];
180 };
181 
182 struct nfsd4_channel_attrs {
183 	u32		headerpadsz;
184 	u32		maxreq_sz;
185 	u32		maxresp_sz;
186 	u32		maxresp_cached;
187 	u32		maxops;
188 	u32		maxreqs;
189 	u32		nr_rdma_attrs;
190 	u32		rdma_attrs;
191 };
192 
193 struct nfsd4_cb_sec {
194 	u32	flavor; /* (u32)(-1) used to mean "no valid flavor" */
195 	kuid_t	uid;
196 	kgid_t	gid;
197 };
198 
199 struct nfsd4_create_session {
200 	clientid_t			clientid;
201 	struct nfs4_sessionid		sessionid;
202 	u32				seqid;
203 	u32				flags;
204 	struct nfsd4_channel_attrs	fore_channel;
205 	struct nfsd4_channel_attrs	back_channel;
206 	u32				callback_prog;
207 	struct nfsd4_cb_sec		cb_sec;
208 };
209 
210 struct nfsd4_backchannel_ctl {
211 	u32	bc_cb_program;
212 	struct nfsd4_cb_sec		bc_cb_sec;
213 };
214 
215 struct nfsd4_bind_conn_to_session {
216 	struct nfs4_sessionid		sessionid;
217 	u32				dir;
218 };
219 
220 /* The single slot clientid cache structure */
221 struct nfsd4_clid_slot {
222 	u32				sl_seqid;
223 	__be32				sl_status;
224 	struct nfsd4_create_session	sl_cr_ses;
225 };
226 
227 struct nfsd4_conn {
228 	struct list_head cn_persession;
229 	struct svc_xprt *cn_xprt;
230 	struct svc_xpt_user cn_xpt_user;
231 	struct nfsd4_session *cn_session;
232 /* CDFC4_FORE, CDFC4_BACK: */
233 	unsigned char cn_flags;
234 };
235 
236 /*
237  * Representation of a v4.1+ session. These are refcounted in a similar fashion
238  * to the nfs4_client. References are only taken when the server is actively
239  * working on the object (primarily during the processing of compounds).
240  */
241 struct nfsd4_session {
242 	atomic_t		se_ref;
243 	struct list_head	se_hash;	/* hash by sessionid */
244 	struct list_head	se_perclnt;
245 /* See SESSION4_PERSIST, etc. for standard flags; this is internal-only: */
246 #define NFS4_SESSION_DEAD	0x010
247 	u32			se_flags;
248 	struct nfs4_client	*se_client;
249 	struct nfs4_sessionid	se_sessionid;
250 	struct nfsd4_channel_attrs se_fchannel;
251 	struct nfsd4_channel_attrs se_bchannel;
252 	struct nfsd4_cb_sec	se_cb_sec;
253 	struct list_head	se_conns;
254 	u32			se_cb_prog;
255 	u32			se_cb_seq_nr;
256 	struct nfsd4_slot	*se_slots[];	/* forward channel slots */
257 };
258 
259 /* formatted contents of nfs4_sessionid */
260 struct nfsd4_sessionid {
261 	clientid_t	clientid;
262 	u32		sequence;
263 	u32		reserved;
264 };
265 
266 #define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
267 
268 /*
269  * struct nfs4_client - one per client.  Clientids live here.
270  *
271  * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0)
272  * or EXCHANGE_ID (for NFSv4.1+). These objects are refcounted and timestamped.
273  * Each nfsd_net_ns object contains a set of these and they are tracked via
274  * short and long form clientid. They are hashed and searched for under the
275  * per-nfsd_net client_lock spinlock.
276  *
277  * References to it are only held during the processing of compounds, and in
278  * certain other operations. In their "resting state" they have a refcount of
279  * 0. If they are not renewed within a lease period, they become eligible for
280  * destruction by the laundromat.
281  *
282  * These objects can also be destroyed prematurely by the fault injection code,
283  * or if the client sends certain forms of SETCLIENTID or EXCHANGE_ID updates.
284  * Care is taken *not* to do this however when the objects have an elevated
285  * refcount.
286  *
287  * o Each nfs4_client is hashed by clientid
288  *
289  * o Each nfs4_clients is also hashed by name (the opaque quantity initially
290  *   sent by the client to identify itself).
291  *
292  * o cl_perclient list is used to ensure no dangling stateowner references
293  *   when we expire the nfs4_client
294  */
295 struct nfs4_client {
296 	struct list_head	cl_idhash; 	/* hash by cl_clientid.id */
297 	struct rb_node		cl_namenode;	/* link into by-name trees */
298 	struct list_head	*cl_ownerstr_hashtbl;
299 	struct list_head	cl_openowners;
300 	struct idr		cl_stateids;	/* stateid lookup */
301 	struct list_head	cl_delegations;
302 	struct list_head	cl_revoked;	/* unacknowledged, revoked 4.1 state */
303 	struct list_head        cl_lru;         /* tail queue */
304 #ifdef CONFIG_NFSD_PNFS
305 	struct list_head	cl_lo_states;	/* outstanding layout states */
306 #endif
307 	struct xdr_netobj	cl_name; 	/* id generated by client */
308 	nfs4_verifier		cl_verifier; 	/* generated by client */
309 	time_t                  cl_time;        /* time of last lease renewal */
310 	struct sockaddr_storage	cl_addr; 	/* client ipaddress */
311 	bool			cl_mach_cred;	/* SP4_MACH_CRED in force */
312 	struct svc_cred		cl_cred; 	/* setclientid principal */
313 	clientid_t		cl_clientid;	/* generated by server */
314 	nfs4_verifier		cl_confirm;	/* generated by server */
315 	u32			cl_minorversion;
316 
317 	/* for v4.0 and v4.1 callbacks: */
318 	struct nfs4_cb_conn	cl_cb_conn;
319 #define NFSD4_CLIENT_CB_UPDATE		(0)
320 #define NFSD4_CLIENT_CB_KILL		(1)
321 #define NFSD4_CLIENT_STABLE		(2)	/* client on stable storage */
322 #define NFSD4_CLIENT_RECLAIM_COMPLETE	(3)	/* reclaim_complete done */
323 #define NFSD4_CLIENT_CONFIRMED		(4)	/* client is confirmed */
324 #define NFSD4_CLIENT_UPCALL_LOCK	(5)	/* upcall serialization */
325 #define NFSD4_CLIENT_CB_FLAG_MASK	(1 << NFSD4_CLIENT_CB_UPDATE | \
326 					 1 << NFSD4_CLIENT_CB_KILL)
327 	unsigned long		cl_flags;
328 	struct rpc_cred		*cl_cb_cred;
329 	struct rpc_clnt		*cl_cb_client;
330 	u32			cl_cb_ident;
331 #define NFSD4_CB_UP		0
332 #define NFSD4_CB_UNKNOWN	1
333 #define NFSD4_CB_DOWN		2
334 #define NFSD4_CB_FAULT		3
335 	int			cl_cb_state;
336 	struct nfsd4_callback	cl_cb_null;
337 	struct nfsd4_session	*cl_cb_session;
338 
339 	/* for all client information that callback code might need: */
340 	spinlock_t		cl_lock;
341 
342 	/* for nfs41 */
343 	struct list_head	cl_sessions;
344 	struct nfsd4_clid_slot	cl_cs_slot;	/* create_session slot */
345 	u32			cl_exchange_flags;
346 	/* number of rpc's in progress over an associated session: */
347 	atomic_t		cl_refcount;
348 	struct nfs4_op_map      cl_spo_must_allow;
349 
350 	/* for nfs41 callbacks */
351 	/* We currently support a single back channel with a single slot */
352 	unsigned long		cl_cb_slot_busy;
353 	struct rpc_wait_queue	cl_cb_waitq;	/* backchannel callers may */
354 						/* wait here for slots */
355 	struct net		*net;
356 };
357 
358 /* struct nfs4_client_reset
359  * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
360  * upon lease reset, or from upcall to state_daemon (to read in state
361  * from non-volitile storage) upon reboot.
362  */
363 struct nfs4_client_reclaim {
364 	struct list_head	cr_strhash;	/* hash by cr_name */
365 	struct nfs4_client	*cr_clp;	/* pointer to associated clp */
366 	char			cr_recdir[HEXDIR_LEN]; /* recover dir */
367 };
368 
369 /* A reasonable value for REPLAY_ISIZE was estimated as follows:
370  * The OPEN response, typically the largest, requires
371  *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) +
372  *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) +
373  *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes
374  */
375 
376 #define NFSD4_REPLAY_ISIZE       112
377 
378 /*
379  * Replay buffer, where the result of the last seqid-mutating operation
380  * is cached.
381  */
382 struct nfs4_replay {
383 	__be32			rp_status;
384 	unsigned int		rp_buflen;
385 	char			*rp_buf;
386 	struct knfsd_fh		rp_openfh;
387 	struct mutex		rp_mutex;
388 	char			rp_ibuf[NFSD4_REPLAY_ISIZE];
389 };
390 
391 struct nfs4_stateowner;
392 
393 struct nfs4_stateowner_operations {
394 	void (*so_unhash)(struct nfs4_stateowner *);
395 	void (*so_free)(struct nfs4_stateowner *);
396 };
397 
398 /*
399  * A core object that represents either an open or lock owner. The object and
400  * lock owner objects have one of these embedded within them. Refcounts and
401  * other fields common to both owner types are contained within these
402  * structures.
403  */
404 struct nfs4_stateowner {
405 	struct list_head			so_strhash;
406 	struct list_head			so_stateids;
407 	struct nfs4_client			*so_client;
408 	const struct nfs4_stateowner_operations	*so_ops;
409 	/* after increment in nfsd4_bump_seqid, represents the next
410 	 * sequence id expected from the client: */
411 	atomic_t				so_count;
412 	u32					so_seqid;
413 	struct xdr_netobj			so_owner; /* open owner name */
414 	struct nfs4_replay			so_replay;
415 	bool					so_is_open_owner;
416 };
417 
418 /*
419  * When a file is opened, the client provides an open state owner opaque string
420  * that indicates the "owner" of that open. These objects are refcounted.
421  * References to it are held by each open state associated with it. This object
422  * is a superset of the nfs4_stateowner struct.
423  */
424 struct nfs4_openowner {
425 	struct nfs4_stateowner	oo_owner; /* must be first field */
426 	struct list_head        oo_perclient;
427 	/*
428 	 * We keep around openowners a little while after last close,
429 	 * which saves clients from having to confirm, and allows us to
430 	 * handle close replays if they come soon enough.  The close_lru
431 	 * is a list of such openowners, to be reaped by the laundromat
432 	 * thread eventually if they remain unused:
433 	 */
434 	struct list_head	oo_close_lru;
435 	struct nfs4_ol_stateid *oo_last_closed_stid;
436 	time_t			oo_time; /* time of placement on so_close_lru */
437 #define NFS4_OO_CONFIRMED   1
438 	unsigned char		oo_flags;
439 };
440 
441 /*
442  * Represents a generic "lockowner". Similar to an openowner. References to it
443  * are held by the lock stateids that are created on its behalf. This object is
444  * a superset of the nfs4_stateowner struct (or would be if it needed any extra
445  * fields).
446  */
447 struct nfs4_lockowner {
448 	struct nfs4_stateowner	lo_owner; /* must be first element */
449 };
450 
451 static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
452 {
453 	return container_of(so, struct nfs4_openowner, oo_owner);
454 }
455 
456 static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
457 {
458 	return container_of(so, struct nfs4_lockowner, lo_owner);
459 }
460 
461 /*
462  * Per-client state indicating no. of opens and outstanding delegations
463  * on a file from a particular client.'od' stands for 'open & delegation'
464  */
465 struct nfs4_clnt_odstate {
466 	struct nfs4_client	*co_client;
467 	struct nfs4_file	*co_file;
468 	struct list_head	co_perfile;
469 	atomic_t		co_odcount;
470 };
471 
472 /*
473  * nfs4_file: a file opened by some number of (open) nfs4_stateowners.
474  *
475  * These objects are global. nfsd keeps one instance of a nfs4_file per
476  * filehandle (though it may keep multiple file descriptors for each). Each
477  * inode can have multiple filehandles associated with it, so there is
478  * (potentially) a many to one relationship between this struct and struct
479  * inode.
480  *
481  * These are hashed by filehandle in the file_hashtbl, which is protected by
482  * the global state_lock spinlock.
483  */
484 struct nfs4_file {
485 	atomic_t		fi_ref;
486 	spinlock_t		fi_lock;
487 	struct hlist_node       fi_hash;	/* hash on fi_fhandle */
488 	struct list_head        fi_stateids;
489 	union {
490 		struct list_head	fi_delegations;
491 		struct rcu_head		fi_rcu;
492 	};
493 	struct list_head	fi_clnt_odstate;
494 	/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
495 	struct file *		fi_fds[3];
496 	/*
497 	 * Each open or lock stateid contributes 0-4 to the counts
498 	 * below depending on which bits are set in st_access_bitmap:
499 	 *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
500 	 *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
501 	 *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
502 	 */
503 	atomic_t		fi_access[2];
504 	u32			fi_share_deny;
505 	struct file		*fi_deleg_file;
506 	int			fi_delegees;
507 	struct knfsd_fh		fi_fhandle;
508 	bool			fi_had_conflict;
509 #ifdef CONFIG_NFSD_PNFS
510 	struct list_head	fi_lo_states;
511 	atomic_t		fi_lo_recalls;
512 #endif
513 };
514 
515 /*
516  * A generic struct representing either a open or lock stateid. The nfs4_client
517  * holds a reference to each of these objects, and they in turn hold a
518  * reference to their respective stateowners. The client's reference is
519  * released in response to a close or unlock (depending on whether it's an open
520  * or lock stateid) or when the client is being destroyed.
521  *
522  * In the case of v4.0 open stateids, these objects are preserved for a little
523  * while after close in order to handle CLOSE replays. Those are eventually
524  * reclaimed via a LRU scheme by the laundromat.
525  *
526  * This object is a superset of the nfs4_stid. "ol" stands for "Open or Lock".
527  * Better suggestions welcome.
528  */
529 struct nfs4_ol_stateid {
530 	struct nfs4_stid		st_stid;
531 	struct list_head		st_perfile;
532 	struct list_head		st_perstateowner;
533 	struct list_head		st_locks;
534 	struct nfs4_stateowner		*st_stateowner;
535 	struct nfs4_clnt_odstate	*st_clnt_odstate;
536 	unsigned char			st_access_bmap;
537 	unsigned char			st_deny_bmap;
538 	struct nfs4_ol_stateid		*st_openstp;
539 	struct mutex			st_mutex;
540 };
541 
542 static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
543 {
544 	return container_of(s, struct nfs4_ol_stateid, st_stid);
545 }
546 
547 struct nfs4_layout_stateid {
548 	struct nfs4_stid		ls_stid;
549 	struct list_head		ls_perclnt;
550 	struct list_head		ls_perfile;
551 	spinlock_t			ls_lock;
552 	struct list_head		ls_layouts;
553 	u32				ls_layout_type;
554 	struct file			*ls_file;
555 	struct nfsd4_callback		ls_recall;
556 	stateid_t			ls_recall_sid;
557 	bool				ls_recalled;
558 	struct mutex			ls_mutex;
559 };
560 
561 static inline struct nfs4_layout_stateid *layoutstateid(struct nfs4_stid *s)
562 {
563 	return container_of(s, struct nfs4_layout_stateid, ls_stid);
564 }
565 
566 /* flags for preprocess_seqid_op() */
567 #define RD_STATE	        0x00000010
568 #define WR_STATE	        0x00000020
569 
570 enum nfsd4_cb_op {
571 	NFSPROC4_CLNT_CB_NULL = 0,
572 	NFSPROC4_CLNT_CB_RECALL,
573 	NFSPROC4_CLNT_CB_LAYOUT,
574 	NFSPROC4_CLNT_CB_SEQUENCE,
575 };
576 
577 /* Returns true iff a is later than b: */
578 static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
579 {
580 	return (s32)(a->si_generation - b->si_generation) > 0;
581 }
582 
583 struct nfsd4_compound_state;
584 struct nfsd_net;
585 
586 extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
587 		struct nfsd4_compound_state *cstate, struct svc_fh *fhp,
588 		stateid_t *stateid, int flags, struct file **filp, bool *tmp_file);
589 __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
590 		     stateid_t *stateid, unsigned char typemask,
591 		     struct nfs4_stid **s, struct nfsd_net *nn);
592 struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl,
593 		struct kmem_cache *slab);
594 void nfs4_unhash_stid(struct nfs4_stid *s);
595 void nfs4_put_stid(struct nfs4_stid *s);
596 void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
597 void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
598 extern void nfs4_release_reclaim(struct nfsd_net *);
599 extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(const char *recdir,
600 							struct nfsd_net *nn);
601 extern __be32 nfs4_check_open_reclaim(clientid_t *clid,
602 		struct nfsd4_compound_state *cstate, struct nfsd_net *nn);
603 extern int set_callback_cred(void);
604 extern void nfsd4_probe_callback(struct nfs4_client *clp);
605 extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
606 extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
607 extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
608 		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
609 extern void nfsd4_run_cb(struct nfsd4_callback *cb);
610 extern int nfsd4_create_callback_queue(void);
611 extern void nfsd4_destroy_callback_queue(void);
612 extern void nfsd4_shutdown_callback(struct nfs4_client *);
613 extern void nfsd4_prepare_cb_recall(struct nfs4_delegation *dp);
614 extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name,
615 							struct nfsd_net *nn);
616 extern bool nfs4_has_reclaimed_state(const char *name, struct nfsd_net *nn);
617 
618 struct nfs4_file *find_file(struct knfsd_fh *fh);
619 void put_nfs4_file(struct nfs4_file *fi);
620 static inline void get_nfs4_file(struct nfs4_file *fi)
621 {
622 	atomic_inc(&fi->fi_ref);
623 }
624 struct file *find_any_file(struct nfs4_file *f);
625 
626 /* grace period management */
627 void nfsd4_end_grace(struct nfsd_net *nn);
628 
629 /* nfs4recover operations */
630 extern int nfsd4_client_tracking_init(struct net *net);
631 extern void nfsd4_client_tracking_exit(struct net *net);
632 extern void nfsd4_client_record_create(struct nfs4_client *clp);
633 extern void nfsd4_client_record_remove(struct nfs4_client *clp);
634 extern int nfsd4_client_record_check(struct nfs4_client *clp);
635 extern void nfsd4_record_grace_done(struct nfsd_net *nn);
636 
637 /* nfs fault injection functions */
638 #ifdef CONFIG_NFSD_FAULT_INJECTION
639 int nfsd_fault_inject_init(void);
640 void nfsd_fault_inject_cleanup(void);
641 
642 u64 nfsd_inject_print_clients(void);
643 u64 nfsd_inject_forget_client(struct sockaddr_storage *, size_t);
644 u64 nfsd_inject_forget_clients(u64);
645 
646 u64 nfsd_inject_print_locks(void);
647 u64 nfsd_inject_forget_client_locks(struct sockaddr_storage *, size_t);
648 u64 nfsd_inject_forget_locks(u64);
649 
650 u64 nfsd_inject_print_openowners(void);
651 u64 nfsd_inject_forget_client_openowners(struct sockaddr_storage *, size_t);
652 u64 nfsd_inject_forget_openowners(u64);
653 
654 u64 nfsd_inject_print_delegations(void);
655 u64 nfsd_inject_forget_client_delegations(struct sockaddr_storage *, size_t);
656 u64 nfsd_inject_forget_delegations(u64);
657 u64 nfsd_inject_recall_client_delegations(struct sockaddr_storage *, size_t);
658 u64 nfsd_inject_recall_delegations(u64);
659 #else /* CONFIG_NFSD_FAULT_INJECTION */
660 static inline int nfsd_fault_inject_init(void) { return 0; }
661 static inline void nfsd_fault_inject_cleanup(void) {}
662 #endif /* CONFIG_NFSD_FAULT_INJECTION */
663 
664 #endif   /* NFSD4_STATE_H */
665