xref: /linux/fs/nfsd/state.h (revision 497e6b37b0099dc415578488287fd84fb74433eb)
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/refcount.h>
40 #include <linux/sunrpc/svc_xprt.h>
41 #include "nfsfh.h"
42 #include "nfsd.h"
43 
44 typedef struct {
45 	u32             cl_boot;
46 	u32             cl_id;
47 } clientid_t;
48 
49 typedef struct {
50 	clientid_t	so_clid;
51 	u32		so_id;
52 } stateid_opaque_t;
53 
54 typedef struct {
55 	u32                     si_generation;
56 	stateid_opaque_t        si_opaque;
57 } stateid_t;
58 
59 typedef struct {
60 	stateid_t		cs_stid;
61 #define NFS4_COPY_STID 1
62 #define NFS4_COPYNOTIFY_STID 2
63 	unsigned char		cs_type;
64 	refcount_t		cs_count;
65 } copy_stateid_t;
66 
67 struct nfsd4_callback {
68 	struct nfs4_client *cb_clp;
69 	struct rpc_message cb_msg;
70 	const struct nfsd4_callback_ops *cb_ops;
71 	struct work_struct cb_work;
72 	int cb_seq_status;
73 	int cb_status;
74 	bool cb_need_restart;
75 	bool cb_holds_slot;
76 };
77 
78 struct nfsd4_callback_ops {
79 	void (*prepare)(struct nfsd4_callback *);
80 	int (*done)(struct nfsd4_callback *, struct rpc_task *);
81 	void (*release)(struct nfsd4_callback *);
82 };
83 
84 /*
85  * A core object that represents a "common" stateid. These are generally
86  * embedded within the different (more specific) stateid objects and contain
87  * fields that are of general use to any stateid.
88  */
89 struct nfs4_stid {
90 	refcount_t		sc_count;
91 #define NFS4_OPEN_STID 1
92 #define NFS4_LOCK_STID 2
93 #define NFS4_DELEG_STID 4
94 /* For an open stateid kept around *only* to process close replays: */
95 #define NFS4_CLOSED_STID 8
96 /* For a deleg stateid kept around only to process free_stateid's: */
97 #define NFS4_REVOKED_DELEG_STID 16
98 #define NFS4_CLOSED_DELEG_STID 32
99 #define NFS4_LAYOUT_STID 64
100 	struct list_head	sc_cp_list;
101 	unsigned char		sc_type;
102 	stateid_t		sc_stateid;
103 	spinlock_t		sc_lock;
104 	struct nfs4_client	*sc_client;
105 	struct nfs4_file	*sc_file;
106 	void			(*sc_free)(struct nfs4_stid *);
107 };
108 
109 /* Keep a list of stateids issued by the COPY_NOTIFY, associate it with the
110  * parent OPEN/LOCK/DELEG stateid.
111  */
112 struct nfs4_cpntf_state {
113 	copy_stateid_t		cp_stateid;
114 	struct list_head	cp_list;	/* per parent nfs4_stid */
115 	stateid_t		cp_p_stateid;	/* copy of parent's stateid */
116 	clientid_t		cp_p_clid;	/* copy of parent's clid */
117 	time64_t		cpntf_time;	/* last time stateid used */
118 };
119 
120 /*
121  * Represents a delegation stateid. The nfs4_client holds references to these
122  * and they are put when it is being destroyed or when the delegation is
123  * returned by the client:
124  *
125  * o 1 reference as long as a delegation is still in force (taken when it's
126  *   alloc'd, put when it's returned or revoked)
127  *
128  * o 1 reference as long as a recall rpc is in progress (taken when the lease
129  *   is broken, put when the rpc exits)
130  *
131  * o 1 more ephemeral reference for each nfsd thread currently doing something
132  *   with that delegation without holding the cl_lock
133  *
134  * If the server attempts to recall a delegation and the client doesn't do so
135  * before a timeout, the server may also revoke the delegation. In that case,
136  * the object will either be destroyed (v4.0) or moved to a per-client list of
137  * revoked delegations (v4.1+).
138  *
139  * This object is a superset of the nfs4_stid.
140  */
141 struct nfs4_delegation {
142 	struct nfs4_stid	dl_stid; /* must be first field */
143 	struct list_head	dl_perfile;
144 	struct list_head	dl_perclnt;
145 	struct list_head	dl_recall_lru;  /* delegation recalled */
146 	struct nfs4_clnt_odstate *dl_clnt_odstate;
147 	u32			dl_type;
148 	time64_t		dl_time;
149 /* For recall: */
150 	int			dl_retries;
151 	struct nfsd4_callback	dl_recall;
152 	bool			dl_recalled;
153 };
154 
155 #define cb_to_delegation(cb) \
156 	container_of(cb, struct nfs4_delegation, dl_recall)
157 
158 /* client delegation callback info */
159 struct nfs4_cb_conn {
160 	/* SETCLIENTID info */
161 	struct sockaddr_storage	cb_addr;
162 	struct sockaddr_storage	cb_saddr;
163 	size_t			cb_addrlen;
164 	u32                     cb_prog; /* used only in 4.0 case;
165 					    per-session otherwise */
166 	u32                     cb_ident;	/* minorversion 0 only */
167 	struct svc_xprt		*cb_xprt;	/* minorversion 1 only */
168 };
169 
170 static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
171 {
172 	return container_of(s, struct nfs4_delegation, dl_stid);
173 }
174 
175 /* Maximum number of slots per session. 160 is useful for long haul TCP */
176 #define NFSD_MAX_SLOTS_PER_SESSION     160
177 /* Maximum number of operations per session compound */
178 #define NFSD_MAX_OPS_PER_COMPOUND	50
179 /* Maximum  session per slot cache size */
180 #define NFSD_SLOT_CACHE_SIZE		2048
181 /* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
182 #define NFSD_CACHE_SIZE_SLOTS_PER_SESSION	32
183 #define NFSD_MAX_MEM_PER_SESSION  \
184 		(NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
185 
186 struct nfsd4_slot {
187 	u32	sl_seqid;
188 	__be32	sl_status;
189 	struct svc_cred sl_cred;
190 	u32	sl_datalen;
191 	u16	sl_opcnt;
192 #define NFSD4_SLOT_INUSE	(1 << 0)
193 #define NFSD4_SLOT_CACHETHIS	(1 << 1)
194 #define NFSD4_SLOT_INITIALIZED	(1 << 2)
195 #define NFSD4_SLOT_CACHED	(1 << 3)
196 	u8	sl_flags;
197 	char	sl_data[];
198 };
199 
200 struct nfsd4_channel_attrs {
201 	u32		headerpadsz;
202 	u32		maxreq_sz;
203 	u32		maxresp_sz;
204 	u32		maxresp_cached;
205 	u32		maxops;
206 	u32		maxreqs;
207 	u32		nr_rdma_attrs;
208 	u32		rdma_attrs;
209 };
210 
211 struct nfsd4_cb_sec {
212 	u32	flavor; /* (u32)(-1) used to mean "no valid flavor" */
213 	kuid_t	uid;
214 	kgid_t	gid;
215 };
216 
217 struct nfsd4_create_session {
218 	clientid_t			clientid;
219 	struct nfs4_sessionid		sessionid;
220 	u32				seqid;
221 	u32				flags;
222 	struct nfsd4_channel_attrs	fore_channel;
223 	struct nfsd4_channel_attrs	back_channel;
224 	u32				callback_prog;
225 	struct nfsd4_cb_sec		cb_sec;
226 };
227 
228 struct nfsd4_backchannel_ctl {
229 	u32	bc_cb_program;
230 	struct nfsd4_cb_sec		bc_cb_sec;
231 };
232 
233 struct nfsd4_bind_conn_to_session {
234 	struct nfs4_sessionid		sessionid;
235 	u32				dir;
236 };
237 
238 /* The single slot clientid cache structure */
239 struct nfsd4_clid_slot {
240 	u32				sl_seqid;
241 	__be32				sl_status;
242 	struct nfsd4_create_session	sl_cr_ses;
243 };
244 
245 struct nfsd4_conn {
246 	struct list_head cn_persession;
247 	struct svc_xprt *cn_xprt;
248 	struct svc_xpt_user cn_xpt_user;
249 	struct nfsd4_session *cn_session;
250 /* CDFC4_FORE, CDFC4_BACK: */
251 	unsigned char cn_flags;
252 };
253 
254 /*
255  * Representation of a v4.1+ session. These are refcounted in a similar fashion
256  * to the nfs4_client. References are only taken when the server is actively
257  * working on the object (primarily during the processing of compounds).
258  */
259 struct nfsd4_session {
260 	atomic_t		se_ref;
261 	struct list_head	se_hash;	/* hash by sessionid */
262 	struct list_head	se_perclnt;
263 /* See SESSION4_PERSIST, etc. for standard flags; this is internal-only: */
264 #define NFS4_SESSION_DEAD	0x010
265 	u32			se_flags;
266 	struct nfs4_client	*se_client;
267 	struct nfs4_sessionid	se_sessionid;
268 	struct nfsd4_channel_attrs se_fchannel;
269 	struct nfsd4_channel_attrs se_bchannel;
270 	struct nfsd4_cb_sec	se_cb_sec;
271 	struct list_head	se_conns;
272 	u32			se_cb_prog;
273 	u32			se_cb_seq_nr;
274 	struct nfsd4_slot	*se_slots[];	/* forward channel slots */
275 };
276 
277 /* formatted contents of nfs4_sessionid */
278 struct nfsd4_sessionid {
279 	clientid_t	clientid;
280 	u32		sequence;
281 	u32		reserved;
282 };
283 
284 #define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
285 
286 /*
287  *       State                Meaning                  Where set
288  * --------------------------------------------------------------------------
289  * | NFSD4_ACTIVE      | Confirmed, active    | Default                     |
290  * |------------------- ----------------------------------------------------|
291  * | NFSD4_COURTESY    | Courtesy state.      | nfs4_get_client_reaplist    |
292  * |                   | Lease/lock/share     |                             |
293  * |                   | reservation conflict |                             |
294  * |                   | can cause Courtesy   |                             |
295  * |                   | client to be expired |                             |
296  * |------------------------------------------------------------------------|
297  * | NFSD4_EXPIRABLE   | Courtesy client to be| nfs4_laundromat             |
298  * |                   | expired by Laundromat| try_to_expire_client        |
299  * |                   | due to conflict      |                             |
300  * |------------------------------------------------------------------------|
301  */
302 enum {
303 	NFSD4_ACTIVE = 0,
304 	NFSD4_COURTESY,
305 	NFSD4_EXPIRABLE,
306 };
307 
308 /*
309  * struct nfs4_client - one per client.  Clientids live here.
310  *
311  * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0)
312  * or EXCHANGE_ID (for NFSv4.1+). These objects are refcounted and timestamped.
313  * Each nfsd_net_ns object contains a set of these and they are tracked via
314  * short and long form clientid. They are hashed and searched for under the
315  * per-nfsd_net client_lock spinlock.
316  *
317  * References to it are only held during the processing of compounds, and in
318  * certain other operations. In their "resting state" they have a refcount of
319  * 0. If they are not renewed within a lease period, they become eligible for
320  * destruction by the laundromat.
321  *
322  * These objects can also be destroyed prematurely by the fault injection code,
323  * or if the client sends certain forms of SETCLIENTID or EXCHANGE_ID updates.
324  * Care is taken *not* to do this however when the objects have an elevated
325  * refcount.
326  *
327  * o Each nfs4_client is hashed by clientid
328  *
329  * o Each nfs4_clients is also hashed by name (the opaque quantity initially
330  *   sent by the client to identify itself).
331  *
332  * o cl_perclient list is used to ensure no dangling stateowner references
333  *   when we expire the nfs4_client
334  */
335 struct nfs4_client {
336 	struct list_head	cl_idhash; 	/* hash by cl_clientid.id */
337 	struct rb_node		cl_namenode;	/* link into by-name trees */
338 	struct list_head	*cl_ownerstr_hashtbl;
339 	struct list_head	cl_openowners;
340 	struct idr		cl_stateids;	/* stateid lookup */
341 	struct list_head	cl_delegations;
342 	struct list_head	cl_revoked;	/* unacknowledged, revoked 4.1 state */
343 	struct list_head        cl_lru;         /* tail queue */
344 #ifdef CONFIG_NFSD_PNFS
345 	struct list_head	cl_lo_states;	/* outstanding layout states */
346 #endif
347 	struct xdr_netobj	cl_name; 	/* id generated by client */
348 	nfs4_verifier		cl_verifier; 	/* generated by client */
349 	time64_t		cl_time;	/* time of last lease renewal */
350 	struct sockaddr_storage	cl_addr; 	/* client ipaddress */
351 	bool			cl_mach_cred;	/* SP4_MACH_CRED in force */
352 	struct svc_cred		cl_cred; 	/* setclientid principal */
353 	clientid_t		cl_clientid;	/* generated by server */
354 	nfs4_verifier		cl_confirm;	/* generated by server */
355 	u32			cl_minorversion;
356 	/* NFSv4.1 client implementation id: */
357 	struct xdr_netobj	cl_nii_domain;
358 	struct xdr_netobj	cl_nii_name;
359 	struct timespec64	cl_nii_time;
360 
361 	/* for v4.0 and v4.1 callbacks: */
362 	struct nfs4_cb_conn	cl_cb_conn;
363 #define NFSD4_CLIENT_CB_UPDATE		(0)
364 #define NFSD4_CLIENT_CB_KILL		(1)
365 #define NFSD4_CLIENT_STABLE		(2)	/* client on stable storage */
366 #define NFSD4_CLIENT_RECLAIM_COMPLETE	(3)	/* reclaim_complete done */
367 #define NFSD4_CLIENT_CONFIRMED		(4)	/* client is confirmed */
368 #define NFSD4_CLIENT_UPCALL_LOCK	(5)	/* upcall serialization */
369 #define NFSD4_CLIENT_CB_FLAG_MASK	(1 << NFSD4_CLIENT_CB_UPDATE | \
370 					 1 << NFSD4_CLIENT_CB_KILL)
371 #define NFSD4_CLIENT_CB_RECALL_ANY	(6)
372 	unsigned long		cl_flags;
373 	const struct cred	*cl_cb_cred;
374 	struct rpc_clnt		*cl_cb_client;
375 	u32			cl_cb_ident;
376 #define NFSD4_CB_UP		0
377 #define NFSD4_CB_UNKNOWN	1
378 #define NFSD4_CB_DOWN		2
379 #define NFSD4_CB_FAULT		3
380 	int			cl_cb_state;
381 	struct nfsd4_callback	cl_cb_null;
382 	struct nfsd4_session	*cl_cb_session;
383 
384 	/* for all client information that callback code might need: */
385 	spinlock_t		cl_lock;
386 
387 	/* for nfs41 */
388 	struct list_head	cl_sessions;
389 	struct nfsd4_clid_slot	cl_cs_slot;	/* create_session slot */
390 	u32			cl_exchange_flags;
391 	/* number of rpc's in progress over an associated session: */
392 	atomic_t		cl_rpc_users;
393 	struct nfsdfs_client	cl_nfsdfs;
394 	struct nfs4_op_map      cl_spo_must_allow;
395 
396 	/* debugging info directory under nfsd/clients/ : */
397 	struct dentry		*cl_nfsd_dentry;
398 	/* 'info' file within that directory. Ref is not counted,
399 	 * but will remain valid iff cl_nfsd_dentry != NULL
400 	 */
401 	struct dentry		*cl_nfsd_info_dentry;
402 
403 	/* for nfs41 callbacks */
404 	/* We currently support a single back channel with a single slot */
405 	unsigned long		cl_cb_slot_busy;
406 	struct rpc_wait_queue	cl_cb_waitq;	/* backchannel callers may */
407 						/* wait here for slots */
408 	struct net		*net;
409 	struct list_head	async_copies;	/* list of async copies */
410 	spinlock_t		async_lock;	/* lock for async copies */
411 	atomic_t		cl_cb_inflight;	/* Outstanding callbacks */
412 
413 	unsigned int		cl_state;
414 	atomic_t		cl_delegs_in_recall;
415 
416 	struct nfsd4_cb_recall_any	*cl_ra;
417 	time64_t		cl_ra_time;
418 	struct list_head	cl_ra_cblist;
419 };
420 
421 /* struct nfs4_client_reset
422  * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
423  * upon lease reset, or from upcall to state_daemon (to read in state
424  * from non-volitile storage) upon reboot.
425  */
426 struct nfs4_client_reclaim {
427 	struct list_head	cr_strhash;	/* hash by cr_name */
428 	struct nfs4_client	*cr_clp;	/* pointer to associated clp */
429 	struct xdr_netobj	cr_name;	/* recovery dir name */
430 	struct xdr_netobj	cr_princhash;
431 };
432 
433 /* A reasonable value for REPLAY_ISIZE was estimated as follows:
434  * The OPEN response, typically the largest, requires
435  *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) +
436  *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) +
437  *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes
438  */
439 
440 #define NFSD4_REPLAY_ISIZE       112
441 
442 /*
443  * Replay buffer, where the result of the last seqid-mutating operation
444  * is cached.
445  */
446 struct nfs4_replay {
447 	__be32			rp_status;
448 	unsigned int		rp_buflen;
449 	char			*rp_buf;
450 	struct knfsd_fh		rp_openfh;
451 	struct mutex		rp_mutex;
452 	char			rp_ibuf[NFSD4_REPLAY_ISIZE];
453 };
454 
455 struct nfs4_stateowner;
456 
457 struct nfs4_stateowner_operations {
458 	void (*so_unhash)(struct nfs4_stateowner *);
459 	void (*so_free)(struct nfs4_stateowner *);
460 };
461 
462 /*
463  * A core object that represents either an open or lock owner. The object and
464  * lock owner objects have one of these embedded within them. Refcounts and
465  * other fields common to both owner types are contained within these
466  * structures.
467  */
468 struct nfs4_stateowner {
469 	struct list_head			so_strhash;
470 	struct list_head			so_stateids;
471 	struct nfs4_client			*so_client;
472 	const struct nfs4_stateowner_operations	*so_ops;
473 	/* after increment in nfsd4_bump_seqid, represents the next
474 	 * sequence id expected from the client: */
475 	atomic_t				so_count;
476 	u32					so_seqid;
477 	struct xdr_netobj			so_owner; /* open owner name */
478 	struct nfs4_replay			so_replay;
479 	bool					so_is_open_owner;
480 };
481 
482 /*
483  * When a file is opened, the client provides an open state owner opaque string
484  * that indicates the "owner" of that open. These objects are refcounted.
485  * References to it are held by each open state associated with it. This object
486  * is a superset of the nfs4_stateowner struct.
487  */
488 struct nfs4_openowner {
489 	struct nfs4_stateowner	oo_owner; /* must be first field */
490 	struct list_head        oo_perclient;
491 	/*
492 	 * We keep around openowners a little while after last close,
493 	 * which saves clients from having to confirm, and allows us to
494 	 * handle close replays if they come soon enough.  The close_lru
495 	 * is a list of such openowners, to be reaped by the laundromat
496 	 * thread eventually if they remain unused:
497 	 */
498 	struct list_head	oo_close_lru;
499 	struct nfs4_ol_stateid *oo_last_closed_stid;
500 	time64_t		oo_time; /* time of placement on so_close_lru */
501 #define NFS4_OO_CONFIRMED   1
502 	unsigned char		oo_flags;
503 };
504 
505 /*
506  * Represents a generic "lockowner". Similar to an openowner. References to it
507  * are held by the lock stateids that are created on its behalf. This object is
508  * a superset of the nfs4_stateowner struct.
509  */
510 struct nfs4_lockowner {
511 	struct nfs4_stateowner	lo_owner;	/* must be first element */
512 	struct list_head	lo_blocked;	/* blocked file_locks */
513 };
514 
515 static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
516 {
517 	return container_of(so, struct nfs4_openowner, oo_owner);
518 }
519 
520 static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
521 {
522 	return container_of(so, struct nfs4_lockowner, lo_owner);
523 }
524 
525 /*
526  * Per-client state indicating no. of opens and outstanding delegations
527  * on a file from a particular client.'od' stands for 'open & delegation'
528  */
529 struct nfs4_clnt_odstate {
530 	struct nfs4_client	*co_client;
531 	struct nfs4_file	*co_file;
532 	struct list_head	co_perfile;
533 	refcount_t		co_odcount;
534 };
535 
536 /*
537  * nfs4_file: a file opened by some number of (open) nfs4_stateowners.
538  *
539  * These objects are global. nfsd keeps one instance of a nfs4_file per
540  * filehandle (though it may keep multiple file descriptors for each). Each
541  * inode can have multiple filehandles associated with it, so there is
542  * (potentially) a many to one relationship between this struct and struct
543  * inode.
544  */
545 struct nfs4_file {
546 	refcount_t		fi_ref;
547 	struct inode *		fi_inode;
548 	bool			fi_aliased;
549 	spinlock_t		fi_lock;
550 	struct rhlist_head	fi_rlist;
551 	struct list_head        fi_stateids;
552 	union {
553 		struct list_head	fi_delegations;
554 		struct rcu_head		fi_rcu;
555 	};
556 	struct list_head	fi_clnt_odstate;
557 	/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
558 	struct nfsd_file	*fi_fds[3];
559 	/*
560 	 * Each open or lock stateid contributes 0-4 to the counts
561 	 * below depending on which bits are set in st_access_bitmap:
562 	 *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
563 	 *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
564 	 *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
565 	 */
566 	atomic_t		fi_access[2];
567 	u32			fi_share_deny;
568 	struct nfsd_file	*fi_deleg_file;
569 	int			fi_delegees;
570 	struct knfsd_fh		fi_fhandle;
571 	bool			fi_had_conflict;
572 #ifdef CONFIG_NFSD_PNFS
573 	struct list_head	fi_lo_states;
574 	atomic_t		fi_lo_recalls;
575 #endif
576 };
577 
578 /*
579  * A generic struct representing either a open or lock stateid. The nfs4_client
580  * holds a reference to each of these objects, and they in turn hold a
581  * reference to their respective stateowners. The client's reference is
582  * released in response to a close or unlock (depending on whether it's an open
583  * or lock stateid) or when the client is being destroyed.
584  *
585  * In the case of v4.0 open stateids, these objects are preserved for a little
586  * while after close in order to handle CLOSE replays. Those are eventually
587  * reclaimed via a LRU scheme by the laundromat.
588  *
589  * This object is a superset of the nfs4_stid. "ol" stands for "Open or Lock".
590  * Better suggestions welcome.
591  */
592 struct nfs4_ol_stateid {
593 	struct nfs4_stid		st_stid;
594 	struct list_head		st_perfile;
595 	struct list_head		st_perstateowner;
596 	struct list_head		st_locks;
597 	struct nfs4_stateowner		*st_stateowner;
598 	struct nfs4_clnt_odstate	*st_clnt_odstate;
599 /*
600  * These bitmasks use 3 separate bits for READ, ALLOW, and BOTH; see the
601  * comment above bmap_to_share_mode() for explanation:
602  */
603 	unsigned char			st_access_bmap;
604 	unsigned char			st_deny_bmap;
605 	struct nfs4_ol_stateid		*st_openstp;
606 	struct mutex			st_mutex;
607 };
608 
609 static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
610 {
611 	return container_of(s, struct nfs4_ol_stateid, st_stid);
612 }
613 
614 struct nfs4_layout_stateid {
615 	struct nfs4_stid		ls_stid;
616 	struct list_head		ls_perclnt;
617 	struct list_head		ls_perfile;
618 	spinlock_t			ls_lock;
619 	struct list_head		ls_layouts;
620 	u32				ls_layout_type;
621 	struct nfsd_file		*ls_file;
622 	struct nfsd4_callback		ls_recall;
623 	stateid_t			ls_recall_sid;
624 	bool				ls_recalled;
625 	struct mutex			ls_mutex;
626 };
627 
628 static inline struct nfs4_layout_stateid *layoutstateid(struct nfs4_stid *s)
629 {
630 	return container_of(s, struct nfs4_layout_stateid, ls_stid);
631 }
632 
633 /* flags for preprocess_seqid_op() */
634 #define RD_STATE	        0x00000010
635 #define WR_STATE	        0x00000020
636 
637 enum nfsd4_cb_op {
638 	NFSPROC4_CLNT_CB_NULL = 0,
639 	NFSPROC4_CLNT_CB_RECALL,
640 	NFSPROC4_CLNT_CB_LAYOUT,
641 	NFSPROC4_CLNT_CB_OFFLOAD,
642 	NFSPROC4_CLNT_CB_SEQUENCE,
643 	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
644 	NFSPROC4_CLNT_CB_RECALL_ANY,
645 };
646 
647 /* Returns true iff a is later than b: */
648 static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
649 {
650 	return (s32)(a->si_generation - b->si_generation) > 0;
651 }
652 
653 /*
654  * When a client tries to get a lock on a file, we set one of these objects
655  * on the blocking lock. When the lock becomes free, we can then issue a
656  * CB_NOTIFY_LOCK to the server.
657  */
658 struct nfsd4_blocked_lock {
659 	struct list_head	nbl_list;
660 	struct list_head	nbl_lru;
661 	time64_t		nbl_time;
662 	struct file_lock	nbl_lock;
663 	struct knfsd_fh		nbl_fh;
664 	struct nfsd4_callback	nbl_cb;
665 	struct kref		nbl_kref;
666 };
667 
668 struct nfsd4_compound_state;
669 struct nfsd_net;
670 struct nfsd4_copy;
671 
672 extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
673 		struct nfsd4_compound_state *cstate, struct svc_fh *fhp,
674 		stateid_t *stateid, int flags, struct nfsd_file **filp,
675 		struct nfs4_stid **cstid);
676 __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
677 		     stateid_t *stateid, unsigned char typemask,
678 		     struct nfs4_stid **s, struct nfsd_net *nn);
679 struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
680 				  void (*sc_free)(struct nfs4_stid *));
681 int nfs4_init_copy_state(struct nfsd_net *nn, struct nfsd4_copy *copy);
682 void nfs4_free_copy_state(struct nfsd4_copy *copy);
683 struct nfs4_cpntf_state *nfs4_alloc_init_cpntf_state(struct nfsd_net *nn,
684 			struct nfs4_stid *p_stid);
685 void nfs4_unhash_stid(struct nfs4_stid *s);
686 void nfs4_put_stid(struct nfs4_stid *s);
687 void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
688 void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
689 extern void nfs4_release_reclaim(struct nfsd_net *);
690 extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(struct xdr_netobj name,
691 							struct nfsd_net *nn);
692 extern __be32 nfs4_check_open_reclaim(struct nfs4_client *);
693 extern void nfsd4_probe_callback(struct nfs4_client *clp);
694 extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
695 extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
696 extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
697 		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
698 extern bool nfsd4_run_cb(struct nfsd4_callback *cb);
699 extern int nfsd4_create_callback_queue(void);
700 extern void nfsd4_destroy_callback_queue(void);
701 extern void nfsd4_shutdown_callback(struct nfs4_client *);
702 extern void nfsd4_shutdown_copy(struct nfs4_client *clp);
703 extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(struct xdr_netobj name,
704 				struct xdr_netobj princhash, struct nfsd_net *nn);
705 extern bool nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn);
706 
707 void put_nfs4_file(struct nfs4_file *fi);
708 extern struct nfsd4_copy *
709 find_async_copy(struct nfs4_client *clp, stateid_t *staetid);
710 extern void nfs4_put_cpntf_state(struct nfsd_net *nn,
711 				 struct nfs4_cpntf_state *cps);
712 extern __be32 manage_cpntf_state(struct nfsd_net *nn, stateid_t *st,
713 				 struct nfs4_client *clp,
714 				 struct nfs4_cpntf_state **cps);
715 static inline void get_nfs4_file(struct nfs4_file *fi)
716 {
717 	refcount_inc(&fi->fi_ref);
718 }
719 struct nfsd_file *find_any_file(struct nfs4_file *f);
720 
721 /* grace period management */
722 void nfsd4_end_grace(struct nfsd_net *nn);
723 
724 /* nfs4recover operations */
725 extern int nfsd4_client_tracking_init(struct net *net);
726 extern void nfsd4_client_tracking_exit(struct net *net);
727 extern void nfsd4_client_record_create(struct nfs4_client *clp);
728 extern void nfsd4_client_record_remove(struct nfs4_client *clp);
729 extern int nfsd4_client_record_check(struct nfs4_client *clp);
730 extern void nfsd4_record_grace_done(struct nfsd_net *nn);
731 
732 static inline bool try_to_expire_client(struct nfs4_client *clp)
733 {
734 	cmpxchg(&clp->cl_state, NFSD4_COURTESY, NFSD4_EXPIRABLE);
735 	return clp->cl_state == NFSD4_EXPIRABLE;
736 }
737 #endif   /* NFSD4_STATE_H */
738