xref: /linux/fs/nfsd/state.h (revision cdd30ebb1b9f36159d66f088b61aee264e649d7a)
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 	int cb_held_slot;
75 	bool cb_need_restart;
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 	uint32_t opcode;
83 };
84 
85 /*
86  * A core object that represents a "common" stateid. These are generally
87  * embedded within the different (more specific) stateid objects and contain
88  * fields that are of general use to any stateid.
89  */
90 struct nfs4_stid {
91 	refcount_t		sc_count;
92 
93 	/* A new stateid is added to the cl_stateids idr early before it
94 	 * is fully initialised.  Its sc_type is then zero.  After
95 	 * initialisation the sc_type it set under cl_lock, and then
96 	 * never changes.
97 	 */
98 #define SC_TYPE_OPEN		BIT(0)
99 #define SC_TYPE_LOCK		BIT(1)
100 #define SC_TYPE_DELEG		BIT(2)
101 #define SC_TYPE_LAYOUT		BIT(3)
102 	unsigned short		sc_type;
103 
104 /* state_lock protects sc_status for delegation stateids.
105  * ->cl_lock protects sc_status for open and lock stateids.
106  * ->st_mutex also protect sc_status for open stateids.
107  * ->ls_lock protects sc_status for layout stateids.
108  */
109 /*
110  * For an open stateid kept around *only* to process close replays.
111  * For deleg stateid, kept in idr until last reference is dropped.
112  */
113 #define SC_STATUS_CLOSED	BIT(0)
114 /* For a deleg stateid kept around only to process free_stateid's: */
115 #define SC_STATUS_REVOKED	BIT(1)
116 #define SC_STATUS_ADMIN_REVOKED	BIT(2)
117 #define SC_STATUS_FREEABLE	BIT(3)
118 #define SC_STATUS_FREED		BIT(4)
119 	unsigned short		sc_status;
120 
121 	struct list_head	sc_cp_list;
122 	stateid_t		sc_stateid;
123 	spinlock_t		sc_lock;
124 	struct nfs4_client	*sc_client;
125 	struct nfs4_file	*sc_file;
126 	void			(*sc_free)(struct nfs4_stid *);
127 };
128 
129 /* Keep a list of stateids issued by the COPY_NOTIFY, associate it with the
130  * parent OPEN/LOCK/DELEG stateid.
131  */
132 struct nfs4_cpntf_state {
133 	copy_stateid_t		cp_stateid;
134 	struct list_head	cp_list;	/* per parent nfs4_stid */
135 	stateid_t		cp_p_stateid;	/* copy of parent's stateid */
136 	clientid_t		cp_p_clid;	/* copy of parent's clid */
137 	time64_t		cpntf_time;	/* last time stateid used */
138 };
139 
140 /*
141  * RFC 7862 Section 4.8 states:
142  *
143  * | A copy offload stateid will be valid until either (A) the client
144  * | or server restarts or (B) the client returns the resource by
145  * | issuing an OFFLOAD_CANCEL operation or the client replies to a
146  * | CB_OFFLOAD operation.
147  *
148  * Because a client might not reply to a CB_OFFLOAD, or a reply
149  * might get lost due to connection loss, NFSD purges async copy
150  * state after a short period to prevent it from accumulating
151  * over time.
152  */
153 #define NFSD_COPY_INITIAL_TTL 10
154 
155 struct nfs4_cb_fattr {
156 	struct nfsd4_callback ncf_getattr;
157 	u32 ncf_cb_status;
158 
159 	/* from CB_GETATTR reply */
160 	u64 ncf_cb_change;
161 	u64 ncf_cb_fsize;
162 
163 	unsigned long ncf_cb_flags;
164 	bool ncf_file_modified;
165 	u64 ncf_initial_cinfo;
166 	u64 ncf_cur_fsize;
167 };
168 
169 /* bits for ncf_cb_flags */
170 #define	CB_GETATTR_BUSY		0
171 
172 /*
173  * Represents a delegation stateid. The nfs4_client holds references to these
174  * and they are put when it is being destroyed or when the delegation is
175  * returned by the client:
176  *
177  * o 1 reference as long as a delegation is still in force (taken when it's
178  *   alloc'd, put when it's returned or revoked)
179  *
180  * o 1 reference as long as a recall rpc is in progress (taken when the lease
181  *   is broken, put when the rpc exits)
182  *
183  * o 1 more ephemeral reference for each nfsd thread currently doing something
184  *   with that delegation without holding the cl_lock
185  *
186  * If the server attempts to recall a delegation and the client doesn't do so
187  * before a timeout, the server may also revoke the delegation. In that case,
188  * the object will either be destroyed (v4.0) or moved to a per-client list of
189  * revoked delegations (v4.1+).
190  *
191  * This object is a superset of the nfs4_stid.
192  */
193 struct nfs4_delegation {
194 	struct nfs4_stid	dl_stid; /* must be first field */
195 	struct list_head	dl_perfile;
196 	struct list_head	dl_perclnt;
197 	struct list_head	dl_recall_lru;  /* delegation recalled */
198 	struct nfs4_clnt_odstate *dl_clnt_odstate;
199 	u32			dl_type;
200 	time64_t		dl_time;
201 /* For recall: */
202 	int			dl_retries;
203 	struct nfsd4_callback	dl_recall;
204 	bool			dl_recalled;
205 
206 	/* for CB_GETATTR */
207 	struct nfs4_cb_fattr    dl_cb_fattr;
208 };
209 
210 #define cb_to_delegation(cb) \
211 	container_of(cb, struct nfs4_delegation, dl_recall)
212 
213 /* client delegation callback info */
214 struct nfs4_cb_conn {
215 	/* SETCLIENTID info */
216 	struct sockaddr_storage	cb_addr;
217 	struct sockaddr_storage	cb_saddr;
218 	size_t			cb_addrlen;
219 	u32                     cb_prog; /* used only in 4.0 case;
220 					    per-session otherwise */
221 	u32                     cb_ident;	/* minorversion 0 only */
222 	struct svc_xprt		*cb_xprt;	/* minorversion 1 only */
223 };
224 
225 static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
226 {
227 	return container_of(s, struct nfs4_delegation, dl_stid);
228 }
229 
230 /* Maximum number of slots per session. 160 is useful for long haul TCP */
231 #define NFSD_MAX_SLOTS_PER_SESSION     160
232 /* Maximum  session per slot cache size */
233 #define NFSD_SLOT_CACHE_SIZE		2048
234 /* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
235 #define NFSD_CACHE_SIZE_SLOTS_PER_SESSION	32
236 #define NFSD_MAX_MEM_PER_SESSION  \
237 		(NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
238 
239 struct nfsd4_slot {
240 	u32	sl_seqid;
241 	__be32	sl_status;
242 	struct svc_cred sl_cred;
243 	u32	sl_datalen;
244 	u16	sl_opcnt;
245 #define NFSD4_SLOT_INUSE	(1 << 0)
246 #define NFSD4_SLOT_CACHETHIS	(1 << 1)
247 #define NFSD4_SLOT_INITIALIZED	(1 << 2)
248 #define NFSD4_SLOT_CACHED	(1 << 3)
249 	u8	sl_flags;
250 	char	sl_data[];
251 };
252 
253 struct nfsd4_channel_attrs {
254 	u32		headerpadsz;
255 	u32		maxreq_sz;
256 	u32		maxresp_sz;
257 	u32		maxresp_cached;
258 	u32		maxops;
259 	u32		maxreqs;
260 	u32		nr_rdma_attrs;
261 	u32		rdma_attrs;
262 };
263 
264 struct nfsd4_cb_sec {
265 	u32	flavor; /* (u32)(-1) used to mean "no valid flavor" */
266 	kuid_t	uid;
267 	kgid_t	gid;
268 };
269 
270 struct nfsd4_create_session {
271 	clientid_t			clientid;
272 	struct nfs4_sessionid		sessionid;
273 	u32				seqid;
274 	u32				flags;
275 	struct nfsd4_channel_attrs	fore_channel;
276 	struct nfsd4_channel_attrs	back_channel;
277 	u32				callback_prog;
278 	struct nfsd4_cb_sec		cb_sec;
279 };
280 
281 struct nfsd4_backchannel_ctl {
282 	u32	bc_cb_program;
283 	struct nfsd4_cb_sec		bc_cb_sec;
284 };
285 
286 struct nfsd4_bind_conn_to_session {
287 	struct nfs4_sessionid		sessionid;
288 	u32				dir;
289 };
290 
291 /* The single slot clientid cache structure */
292 struct nfsd4_clid_slot {
293 	u32				sl_seqid;
294 	__be32				sl_status;
295 	struct nfsd4_create_session	sl_cr_ses;
296 };
297 
298 struct nfsd4_conn {
299 	struct list_head cn_persession;
300 	struct svc_xprt *cn_xprt;
301 	struct svc_xpt_user cn_xpt_user;
302 	struct nfsd4_session *cn_session;
303 /* CDFC4_FORE, CDFC4_BACK: */
304 	unsigned char cn_flags;
305 };
306 
307 /* Maximum number of slots that nfsd will use in the backchannel */
308 #define NFSD_BC_SLOT_TABLE_SIZE		(sizeof(u32) * 8)
309 
310 /*
311  * Representation of a v4.1+ session. These are refcounted in a similar fashion
312  * to the nfs4_client. References are only taken when the server is actively
313  * working on the object (primarily during the processing of compounds).
314  */
315 struct nfsd4_session {
316 	atomic_t		se_ref;
317 	spinlock_t		se_lock;
318 	u32			se_cb_slot_avail; /* bitmap of available slots */
319 	u32			se_cb_highest_slot;	/* highest slot client wants */
320 	u32			se_cb_prog;
321 	bool			se_dead;
322 	struct list_head	se_hash;	/* hash by sessionid */
323 	struct list_head	se_perclnt;
324 	struct nfs4_client	*se_client;
325 	struct nfs4_sessionid	se_sessionid;
326 	struct nfsd4_channel_attrs se_fchannel;
327 	struct nfsd4_cb_sec	se_cb_sec;
328 	struct list_head	se_conns;
329 	u32			se_cb_seq_nr[NFSD_BC_SLOT_TABLE_SIZE];
330 	struct nfsd4_slot	*se_slots[];	/* forward channel slots */
331 };
332 
333 /* formatted contents of nfs4_sessionid */
334 struct nfsd4_sessionid {
335 	clientid_t	clientid;
336 	u32		sequence;
337 	u32		reserved;
338 };
339 
340 #define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
341 
342 /*
343  *       State                Meaning                  Where set
344  * --------------------------------------------------------------------------
345  * | NFSD4_ACTIVE      | Confirmed, active    | Default                     |
346  * |------------------- ----------------------------------------------------|
347  * | NFSD4_COURTESY    | Courtesy state.      | nfs4_get_client_reaplist    |
348  * |                   | Lease/lock/share     |                             |
349  * |                   | reservation conflict |                             |
350  * |                   | can cause Courtesy   |                             |
351  * |                   | client to be expired |                             |
352  * |------------------------------------------------------------------------|
353  * | NFSD4_EXPIRABLE   | Courtesy client to be| nfs4_laundromat             |
354  * |                   | expired by Laundromat| try_to_expire_client        |
355  * |                   | due to conflict      |                             |
356  * |------------------------------------------------------------------------|
357  */
358 enum {
359 	NFSD4_ACTIVE = 0,
360 	NFSD4_COURTESY,
361 	NFSD4_EXPIRABLE,
362 };
363 
364 /*
365  * struct nfs4_client - one per client.  Clientids live here.
366  *
367  * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0)
368  * or EXCHANGE_ID (for NFSv4.1+). These objects are refcounted and timestamped.
369  * Each nfsd_net_ns object contains a set of these and they are tracked via
370  * short and long form clientid. They are hashed and searched for under the
371  * per-nfsd_net client_lock spinlock.
372  *
373  * References to it are only held during the processing of compounds, and in
374  * certain other operations. In their "resting state" they have a refcount of
375  * 0. If they are not renewed within a lease period, they become eligible for
376  * destruction by the laundromat.
377  *
378  * These objects can also be destroyed if the client sends certain forms of
379  * SETCLIENTID or EXCHANGE_ID operations.
380  *
381  * Care is taken *not* to do this however when the objects have an elevated
382  * refcount.
383  *
384  * o Each nfs4_client is hashed by clientid
385  *
386  * o Each nfs4_clients is also hashed by name (the opaque quantity initially
387  *   sent by the client to identify itself).
388  *
389  * o cl_perclient list is used to ensure no dangling stateowner references
390  *   when we expire the nfs4_client
391  */
392 struct nfs4_client {
393 	struct list_head	cl_idhash; 	/* hash by cl_clientid.id */
394 	struct rb_node		cl_namenode;	/* link into by-name trees */
395 	struct list_head	*cl_ownerstr_hashtbl;
396 	struct list_head	cl_openowners;
397 	struct idr		cl_stateids;	/* stateid lookup */
398 	struct list_head	cl_delegations;
399 	struct list_head	cl_revoked;	/* unacknowledged, revoked 4.1 state */
400 	struct list_head        cl_lru;         /* tail queue */
401 #ifdef CONFIG_NFSD_PNFS
402 	struct list_head	cl_lo_states;	/* outstanding layout states */
403 #endif
404 	struct xdr_netobj	cl_name; 	/* id generated by client */
405 	nfs4_verifier		cl_verifier; 	/* generated by client */
406 	time64_t		cl_time;	/* time of last lease renewal */
407 	struct sockaddr_storage	cl_addr; 	/* client ipaddress */
408 	bool			cl_mach_cred;	/* SP4_MACH_CRED in force */
409 	struct svc_cred		cl_cred; 	/* setclientid principal */
410 	clientid_t		cl_clientid;	/* generated by server */
411 	nfs4_verifier		cl_confirm;	/* generated by server */
412 	u32			cl_minorversion;
413 	atomic_t		cl_admin_revoked; /* count of admin-revoked states */
414 	/* NFSv4.1 client implementation id: */
415 	struct xdr_netobj	cl_nii_domain;
416 	struct xdr_netobj	cl_nii_name;
417 	struct timespec64	cl_nii_time;
418 
419 	/* for v4.0 and v4.1 callbacks: */
420 	struct nfs4_cb_conn	cl_cb_conn;
421 #define NFSD4_CLIENT_CB_UPDATE		(0)
422 #define NFSD4_CLIENT_CB_KILL		(1)
423 #define NFSD4_CLIENT_STABLE		(2)	/* client on stable storage */
424 #define NFSD4_CLIENT_RECLAIM_COMPLETE	(3)	/* reclaim_complete done */
425 #define NFSD4_CLIENT_CONFIRMED		(4)	/* client is confirmed */
426 #define NFSD4_CLIENT_UPCALL_LOCK	(5)	/* upcall serialization */
427 #define NFSD4_CLIENT_CB_FLAG_MASK	(1 << NFSD4_CLIENT_CB_UPDATE | \
428 					 1 << NFSD4_CLIENT_CB_KILL)
429 #define NFSD4_CLIENT_CB_RECALL_ANY	(6)
430 	unsigned long		cl_flags;
431 
432 	struct workqueue_struct *cl_callback_wq;
433 	const struct cred	*cl_cb_cred;
434 	struct rpc_clnt		*cl_cb_client;
435 	u32			cl_cb_ident;
436 #define NFSD4_CB_UP		0
437 #define NFSD4_CB_UNKNOWN	1
438 #define NFSD4_CB_DOWN		2
439 #define NFSD4_CB_FAULT		3
440 	int			cl_cb_state;
441 	struct nfsd4_callback	cl_cb_null;
442 	struct nfsd4_session	*cl_cb_session;
443 
444 	/* for all client information that callback code might need: */
445 	spinlock_t		cl_lock;
446 
447 	/* for nfs41 */
448 	struct list_head	cl_sessions;
449 	struct nfsd4_clid_slot	cl_cs_slot;	/* create_session slot */
450 	u32			cl_exchange_flags;
451 	/* number of rpc's in progress over an associated session: */
452 	atomic_t		cl_rpc_users;
453 	struct nfsdfs_client	cl_nfsdfs;
454 	struct nfs4_op_map      cl_spo_must_allow;
455 
456 	/* debugging info directory under nfsd/clients/ : */
457 	struct dentry		*cl_nfsd_dentry;
458 	/* 'info' file within that directory. Ref is not counted,
459 	 * but will remain valid iff cl_nfsd_dentry != NULL
460 	 */
461 	struct dentry		*cl_nfsd_info_dentry;
462 
463 	struct rpc_wait_queue	cl_cb_waitq;	/* backchannel callers may */
464 						/* wait here for slots */
465 	struct net		*net;
466 	struct list_head	async_copies;	/* list of async copies */
467 	spinlock_t		async_lock;	/* lock for async copies */
468 	atomic_t		cl_cb_inflight;	/* Outstanding callbacks */
469 
470 	unsigned int		cl_state;
471 	atomic_t		cl_delegs_in_recall;
472 
473 	struct nfsd4_cb_recall_any	*cl_ra;
474 	time64_t		cl_ra_time;
475 	struct list_head	cl_ra_cblist;
476 };
477 
478 /* struct nfs4_client_reset
479  * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
480  * upon lease reset, or from upcall to state_daemon (to read in state
481  * from non-volitile storage) upon reboot.
482  */
483 struct nfs4_client_reclaim {
484 	struct list_head	cr_strhash;	/* hash by cr_name */
485 	struct nfs4_client	*cr_clp;	/* pointer to associated clp */
486 	struct xdr_netobj	cr_name;	/* recovery dir name */
487 	struct xdr_netobj	cr_princhash;
488 };
489 
490 /* A reasonable value for REPLAY_ISIZE was estimated as follows:
491  * The OPEN response, typically the largest, requires
492  *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) +
493  *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) +
494  *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes
495  */
496 
497 #define NFSD4_REPLAY_ISIZE       112
498 
499 /*
500  * Replay buffer, where the result of the last seqid-mutating operation
501  * is cached.
502  */
503 struct nfs4_replay {
504 	__be32			rp_status;
505 	unsigned int		rp_buflen;
506 	char			*rp_buf;
507 	struct knfsd_fh		rp_openfh;
508 	atomic_t		rp_locked;
509 	char			rp_ibuf[NFSD4_REPLAY_ISIZE];
510 };
511 
512 struct nfs4_stateowner;
513 
514 struct nfs4_stateowner_operations {
515 	void (*so_unhash)(struct nfs4_stateowner *);
516 	void (*so_free)(struct nfs4_stateowner *);
517 };
518 
519 /*
520  * A core object that represents either an open or lock owner. The object and
521  * lock owner objects have one of these embedded within them. Refcounts and
522  * other fields common to both owner types are contained within these
523  * structures.
524  */
525 struct nfs4_stateowner {
526 	struct list_head			so_strhash;
527 	struct list_head			so_stateids;
528 	struct nfs4_client			*so_client;
529 	const struct nfs4_stateowner_operations	*so_ops;
530 	/* after increment in nfsd4_bump_seqid, represents the next
531 	 * sequence id expected from the client: */
532 	atomic_t				so_count;
533 	u32					so_seqid;
534 	struct xdr_netobj			so_owner; /* open owner name */
535 	struct nfs4_replay			so_replay;
536 	bool					so_is_open_owner;
537 };
538 
539 /*
540  * When a file is opened, the client provides an open state owner opaque string
541  * that indicates the "owner" of that open. These objects are refcounted.
542  * References to it are held by each open state associated with it. This object
543  * is a superset of the nfs4_stateowner struct.
544  */
545 struct nfs4_openowner {
546 	struct nfs4_stateowner	oo_owner; /* must be first field */
547 	struct list_head        oo_perclient;
548 	/*
549 	 * We keep around openowners a little while after last close,
550 	 * which saves clients from having to confirm, and allows us to
551 	 * handle close replays if they come soon enough.  The close_lru
552 	 * is a list of such openowners, to be reaped by the laundromat
553 	 * thread eventually if they remain unused:
554 	 */
555 	struct list_head	oo_close_lru;
556 	struct nfs4_ol_stateid *oo_last_closed_stid;
557 	time64_t		oo_time; /* time of placement on so_close_lru */
558 #define NFS4_OO_CONFIRMED   1
559 	unsigned char		oo_flags;
560 };
561 
562 /*
563  * Represents a generic "lockowner". Similar to an openowner. References to it
564  * are held by the lock stateids that are created on its behalf. This object is
565  * a superset of the nfs4_stateowner struct.
566  */
567 struct nfs4_lockowner {
568 	struct nfs4_stateowner	lo_owner;	/* must be first element */
569 	struct list_head	lo_blocked;	/* blocked file_locks */
570 };
571 
572 static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
573 {
574 	return container_of(so, struct nfs4_openowner, oo_owner);
575 }
576 
577 static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
578 {
579 	return container_of(so, struct nfs4_lockowner, lo_owner);
580 }
581 
582 /*
583  * Per-client state indicating no. of opens and outstanding delegations
584  * on a file from a particular client.'od' stands for 'open & delegation'
585  */
586 struct nfs4_clnt_odstate {
587 	struct nfs4_client	*co_client;
588 	struct nfs4_file	*co_file;
589 	struct list_head	co_perfile;
590 	refcount_t		co_odcount;
591 };
592 
593 /*
594  * nfs4_file: a file opened by some number of (open) nfs4_stateowners.
595  *
596  * These objects are global. nfsd keeps one instance of a nfs4_file per
597  * filehandle (though it may keep multiple file descriptors for each). Each
598  * inode can have multiple filehandles associated with it, so there is
599  * (potentially) a many to one relationship between this struct and struct
600  * inode.
601  */
602 struct nfs4_file {
603 	refcount_t		fi_ref;
604 	struct inode *		fi_inode;
605 	bool			fi_aliased;
606 	spinlock_t		fi_lock;
607 	struct rhlist_head	fi_rlist;
608 	struct list_head        fi_stateids;
609 	union {
610 		struct list_head	fi_delegations;
611 		struct rcu_head		fi_rcu;
612 	};
613 	struct list_head	fi_clnt_odstate;
614 	/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
615 	struct nfsd_file	*fi_fds[3];
616 	/*
617 	 * Each open or lock stateid contributes 0-4 to the counts
618 	 * below depending on which bits are set in st_access_bitmap:
619 	 *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
620 	 *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
621 	 *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
622 	 */
623 	atomic_t		fi_access[2];
624 	u32			fi_share_deny;
625 	struct nfsd_file	*fi_deleg_file;
626 	int			fi_delegees;
627 	struct knfsd_fh		fi_fhandle;
628 	bool			fi_had_conflict;
629 #ifdef CONFIG_NFSD_PNFS
630 	struct list_head	fi_lo_states;
631 	atomic_t		fi_lo_recalls;
632 #endif
633 };
634 
635 /*
636  * A generic struct representing either a open or lock stateid. The nfs4_client
637  * holds a reference to each of these objects, and they in turn hold a
638  * reference to their respective stateowners. The client's reference is
639  * released in response to a close or unlock (depending on whether it's an open
640  * or lock stateid) or when the client is being destroyed.
641  *
642  * In the case of v4.0 open stateids, these objects are preserved for a little
643  * while after close in order to handle CLOSE replays. Those are eventually
644  * reclaimed via a LRU scheme by the laundromat.
645  *
646  * This object is a superset of the nfs4_stid. "ol" stands for "Open or Lock".
647  * Better suggestions welcome.
648  */
649 struct nfs4_ol_stateid {
650 	struct nfs4_stid		st_stid;
651 	struct list_head		st_perfile;
652 	struct list_head		st_perstateowner;
653 	struct list_head		st_locks;
654 	struct nfs4_stateowner		*st_stateowner;
655 	struct nfs4_clnt_odstate	*st_clnt_odstate;
656 /*
657  * These bitmasks use 3 separate bits for READ, ALLOW, and BOTH; see the
658  * comment above bmap_to_share_mode() for explanation:
659  */
660 	unsigned char			st_access_bmap;
661 	unsigned char			st_deny_bmap;
662 	struct nfs4_ol_stateid		*st_openstp;
663 	struct mutex			st_mutex;
664 };
665 
666 static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
667 {
668 	return container_of(s, struct nfs4_ol_stateid, st_stid);
669 }
670 
671 struct nfs4_layout_stateid {
672 	struct nfs4_stid		ls_stid;
673 	struct list_head		ls_perclnt;
674 	struct list_head		ls_perfile;
675 	spinlock_t			ls_lock;
676 	struct list_head		ls_layouts;
677 	u32				ls_layout_type;
678 	struct nfsd_file		*ls_file;
679 	struct nfsd4_callback		ls_recall;
680 	stateid_t			ls_recall_sid;
681 	bool				ls_recalled;
682 	struct mutex			ls_mutex;
683 };
684 
685 static inline struct nfs4_layout_stateid *layoutstateid(struct nfs4_stid *s)
686 {
687 	return container_of(s, struct nfs4_layout_stateid, ls_stid);
688 }
689 
690 /* flags for preprocess_seqid_op() */
691 #define RD_STATE	        0x00000010
692 #define WR_STATE	        0x00000020
693 
694 enum nfsd4_cb_op {
695 	NFSPROC4_CLNT_CB_NULL = 0,
696 	NFSPROC4_CLNT_CB_RECALL,
697 	NFSPROC4_CLNT_CB_LAYOUT,
698 	NFSPROC4_CLNT_CB_OFFLOAD,
699 	NFSPROC4_CLNT_CB_SEQUENCE,
700 	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
701 	NFSPROC4_CLNT_CB_RECALL_ANY,
702 	NFSPROC4_CLNT_CB_GETATTR,
703 };
704 
705 /* Returns true iff a is later than b: */
706 static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
707 {
708 	return (s32)(a->si_generation - b->si_generation) > 0;
709 }
710 
711 /*
712  * When a client tries to get a lock on a file, we set one of these objects
713  * on the blocking lock. When the lock becomes free, we can then issue a
714  * CB_NOTIFY_LOCK to the server.
715  */
716 struct nfsd4_blocked_lock {
717 	struct list_head	nbl_list;
718 	struct list_head	nbl_lru;
719 	time64_t		nbl_time;
720 	struct file_lock	nbl_lock;
721 	struct knfsd_fh		nbl_fh;
722 	struct nfsd4_callback	nbl_cb;
723 	struct kref		nbl_kref;
724 };
725 
726 struct nfsd4_compound_state;
727 struct nfsd_net;
728 struct nfsd4_copy;
729 
730 extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
731 		struct nfsd4_compound_state *cstate, struct svc_fh *fhp,
732 		stateid_t *stateid, int flags, struct nfsd_file **filp,
733 		struct nfs4_stid **cstid);
734 __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
735 			    stateid_t *stateid, unsigned short typemask,
736 			    unsigned short statusmask,
737 			    struct nfs4_stid **s, struct nfsd_net *nn);
738 struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
739 				  void (*sc_free)(struct nfs4_stid *));
740 int nfs4_init_copy_state(struct nfsd_net *nn, struct nfsd4_copy *copy);
741 void nfs4_free_copy_state(struct nfsd4_copy *copy);
742 struct nfs4_cpntf_state *nfs4_alloc_init_cpntf_state(struct nfsd_net *nn,
743 			struct nfs4_stid *p_stid);
744 void nfs4_put_stid(struct nfs4_stid *s);
745 void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
746 void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
747 extern void nfs4_release_reclaim(struct nfsd_net *);
748 extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(struct xdr_netobj name,
749 							struct nfsd_net *nn);
750 extern __be32 nfs4_check_open_reclaim(struct nfs4_client *);
751 extern void nfsd4_probe_callback(struct nfs4_client *clp);
752 extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
753 extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
754 extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
755 		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
756 extern bool nfsd4_run_cb(struct nfsd4_callback *cb);
757 extern void nfsd4_shutdown_callback(struct nfs4_client *);
758 extern void nfsd4_shutdown_copy(struct nfs4_client *clp);
759 void nfsd4_async_copy_reaper(struct nfsd_net *nn);
760 bool nfsd4_has_active_async_copies(struct nfs4_client *clp);
761 extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(struct xdr_netobj name,
762 				struct xdr_netobj princhash, struct nfsd_net *nn);
763 extern bool nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn);
764 
765 void put_nfs4_file(struct nfs4_file *fi);
766 extern void nfs4_put_cpntf_state(struct nfsd_net *nn,
767 				 struct nfs4_cpntf_state *cps);
768 extern __be32 manage_cpntf_state(struct nfsd_net *nn, stateid_t *st,
769 				 struct nfs4_client *clp,
770 				 struct nfs4_cpntf_state **cps);
771 static inline void get_nfs4_file(struct nfs4_file *fi)
772 {
773 	refcount_inc(&fi->fi_ref);
774 }
775 struct nfsd_file *find_any_file(struct nfs4_file *f);
776 
777 #ifdef CONFIG_NFSD_V4
778 void nfsd4_revoke_states(struct net *net, struct super_block *sb);
779 #else
780 static inline void nfsd4_revoke_states(struct net *net, struct super_block *sb)
781 {
782 }
783 #endif
784 
785 /* grace period management */
786 void nfsd4_end_grace(struct nfsd_net *nn);
787 
788 /* nfs4recover operations */
789 extern int nfsd4_client_tracking_init(struct net *net);
790 extern void nfsd4_client_tracking_exit(struct net *net);
791 extern void nfsd4_client_record_create(struct nfs4_client *clp);
792 extern void nfsd4_client_record_remove(struct nfs4_client *clp);
793 extern int nfsd4_client_record_check(struct nfs4_client *clp);
794 extern void nfsd4_record_grace_done(struct nfsd_net *nn);
795 
796 static inline bool try_to_expire_client(struct nfs4_client *clp)
797 {
798 	cmpxchg(&clp->cl_state, NFSD4_COURTESY, NFSD4_EXPIRABLE);
799 	return clp->cl_state == NFSD4_EXPIRABLE;
800 }
801 
802 extern __be32 nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp,
803 		struct dentry *dentry, struct nfs4_delegation **pdp);
804 #endif   /* NFSD4_STATE_H */
805