xref: /linux/fs/nfsd/state.h (revision 55d0969c451159cff86949b38c39171cab962069)
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 	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 	unsigned short		sc_status;
118 
119 	struct list_head	sc_cp_list;
120 	stateid_t		sc_stateid;
121 	spinlock_t		sc_lock;
122 	struct nfs4_client	*sc_client;
123 	struct nfs4_file	*sc_file;
124 	void			(*sc_free)(struct nfs4_stid *);
125 };
126 
127 /* Keep a list of stateids issued by the COPY_NOTIFY, associate it with the
128  * parent OPEN/LOCK/DELEG stateid.
129  */
130 struct nfs4_cpntf_state {
131 	copy_stateid_t		cp_stateid;
132 	struct list_head	cp_list;	/* per parent nfs4_stid */
133 	stateid_t		cp_p_stateid;	/* copy of parent's stateid */
134 	clientid_t		cp_p_clid;	/* copy of parent's clid */
135 	time64_t		cpntf_time;	/* last time stateid used */
136 };
137 
138 struct nfs4_cb_fattr {
139 	struct nfsd4_callback ncf_getattr;
140 	u32 ncf_cb_status;
141 	u32 ncf_cb_bmap[1];
142 
143 	/* from CB_GETATTR reply */
144 	u64 ncf_cb_change;
145 	u64 ncf_cb_fsize;
146 
147 	unsigned long ncf_cb_flags;
148 	bool ncf_file_modified;
149 	u64 ncf_initial_cinfo;
150 	u64 ncf_cur_fsize;
151 };
152 
153 /* bits for ncf_cb_flags */
154 #define	CB_GETATTR_BUSY		0
155 
156 /*
157  * Represents a delegation stateid. The nfs4_client holds references to these
158  * and they are put when it is being destroyed or when the delegation is
159  * returned by the client:
160  *
161  * o 1 reference as long as a delegation is still in force (taken when it's
162  *   alloc'd, put when it's returned or revoked)
163  *
164  * o 1 reference as long as a recall rpc is in progress (taken when the lease
165  *   is broken, put when the rpc exits)
166  *
167  * o 1 more ephemeral reference for each nfsd thread currently doing something
168  *   with that delegation without holding the cl_lock
169  *
170  * If the server attempts to recall a delegation and the client doesn't do so
171  * before a timeout, the server may also revoke the delegation. In that case,
172  * the object will either be destroyed (v4.0) or moved to a per-client list of
173  * revoked delegations (v4.1+).
174  *
175  * This object is a superset of the nfs4_stid.
176  */
177 struct nfs4_delegation {
178 	struct nfs4_stid	dl_stid; /* must be first field */
179 	struct list_head	dl_perfile;
180 	struct list_head	dl_perclnt;
181 	struct list_head	dl_recall_lru;  /* delegation recalled */
182 	struct nfs4_clnt_odstate *dl_clnt_odstate;
183 	u32			dl_type;
184 	time64_t		dl_time;
185 /* For recall: */
186 	int			dl_retries;
187 	struct nfsd4_callback	dl_recall;
188 	bool			dl_recalled;
189 
190 	/* for CB_GETATTR */
191 	struct nfs4_cb_fattr    dl_cb_fattr;
192 };
193 
194 #define cb_to_delegation(cb) \
195 	container_of(cb, struct nfs4_delegation, dl_recall)
196 
197 /* client delegation callback info */
198 struct nfs4_cb_conn {
199 	/* SETCLIENTID info */
200 	struct sockaddr_storage	cb_addr;
201 	struct sockaddr_storage	cb_saddr;
202 	size_t			cb_addrlen;
203 	u32                     cb_prog; /* used only in 4.0 case;
204 					    per-session otherwise */
205 	u32                     cb_ident;	/* minorversion 0 only */
206 	struct svc_xprt		*cb_xprt;	/* minorversion 1 only */
207 };
208 
209 static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
210 {
211 	return container_of(s, struct nfs4_delegation, dl_stid);
212 }
213 
214 /* Maximum number of slots per session. 160 is useful for long haul TCP */
215 #define NFSD_MAX_SLOTS_PER_SESSION     160
216 /* Maximum  session per slot cache size */
217 #define NFSD_SLOT_CACHE_SIZE		2048
218 /* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
219 #define NFSD_CACHE_SIZE_SLOTS_PER_SESSION	32
220 #define NFSD_MAX_MEM_PER_SESSION  \
221 		(NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
222 
223 struct nfsd4_slot {
224 	u32	sl_seqid;
225 	__be32	sl_status;
226 	struct svc_cred sl_cred;
227 	u32	sl_datalen;
228 	u16	sl_opcnt;
229 #define NFSD4_SLOT_INUSE	(1 << 0)
230 #define NFSD4_SLOT_CACHETHIS	(1 << 1)
231 #define NFSD4_SLOT_INITIALIZED	(1 << 2)
232 #define NFSD4_SLOT_CACHED	(1 << 3)
233 	u8	sl_flags;
234 	char	sl_data[];
235 };
236 
237 struct nfsd4_channel_attrs {
238 	u32		headerpadsz;
239 	u32		maxreq_sz;
240 	u32		maxresp_sz;
241 	u32		maxresp_cached;
242 	u32		maxops;
243 	u32		maxreqs;
244 	u32		nr_rdma_attrs;
245 	u32		rdma_attrs;
246 };
247 
248 struct nfsd4_cb_sec {
249 	u32	flavor; /* (u32)(-1) used to mean "no valid flavor" */
250 	kuid_t	uid;
251 	kgid_t	gid;
252 };
253 
254 struct nfsd4_create_session {
255 	clientid_t			clientid;
256 	struct nfs4_sessionid		sessionid;
257 	u32				seqid;
258 	u32				flags;
259 	struct nfsd4_channel_attrs	fore_channel;
260 	struct nfsd4_channel_attrs	back_channel;
261 	u32				callback_prog;
262 	struct nfsd4_cb_sec		cb_sec;
263 };
264 
265 struct nfsd4_backchannel_ctl {
266 	u32	bc_cb_program;
267 	struct nfsd4_cb_sec		bc_cb_sec;
268 };
269 
270 struct nfsd4_bind_conn_to_session {
271 	struct nfs4_sessionid		sessionid;
272 	u32				dir;
273 };
274 
275 /* The single slot clientid cache structure */
276 struct nfsd4_clid_slot {
277 	u32				sl_seqid;
278 	__be32				sl_status;
279 	struct nfsd4_create_session	sl_cr_ses;
280 };
281 
282 struct nfsd4_conn {
283 	struct list_head cn_persession;
284 	struct svc_xprt *cn_xprt;
285 	struct svc_xpt_user cn_xpt_user;
286 	struct nfsd4_session *cn_session;
287 /* CDFC4_FORE, CDFC4_BACK: */
288 	unsigned char cn_flags;
289 };
290 
291 /*
292  * Representation of a v4.1+ session. These are refcounted in a similar fashion
293  * to the nfs4_client. References are only taken when the server is actively
294  * working on the object (primarily during the processing of compounds).
295  */
296 struct nfsd4_session {
297 	atomic_t		se_ref;
298 	struct list_head	se_hash;	/* hash by sessionid */
299 	struct list_head	se_perclnt;
300 /* See SESSION4_PERSIST, etc. for standard flags; this is internal-only: */
301 #define NFS4_SESSION_DEAD	0x010
302 	u32			se_flags;
303 	struct nfs4_client	*se_client;
304 	struct nfs4_sessionid	se_sessionid;
305 	struct nfsd4_channel_attrs se_fchannel;
306 	struct nfsd4_channel_attrs se_bchannel;
307 	struct nfsd4_cb_sec	se_cb_sec;
308 	struct list_head	se_conns;
309 	u32			se_cb_prog;
310 	u32			se_cb_seq_nr;
311 	struct nfsd4_slot	*se_slots[];	/* forward channel slots */
312 };
313 
314 /* formatted contents of nfs4_sessionid */
315 struct nfsd4_sessionid {
316 	clientid_t	clientid;
317 	u32		sequence;
318 	u32		reserved;
319 };
320 
321 #define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
322 
323 /*
324  *       State                Meaning                  Where set
325  * --------------------------------------------------------------------------
326  * | NFSD4_ACTIVE      | Confirmed, active    | Default                     |
327  * |------------------- ----------------------------------------------------|
328  * | NFSD4_COURTESY    | Courtesy state.      | nfs4_get_client_reaplist    |
329  * |                   | Lease/lock/share     |                             |
330  * |                   | reservation conflict |                             |
331  * |                   | can cause Courtesy   |                             |
332  * |                   | client to be expired |                             |
333  * |------------------------------------------------------------------------|
334  * | NFSD4_EXPIRABLE   | Courtesy client to be| nfs4_laundromat             |
335  * |                   | expired by Laundromat| try_to_expire_client        |
336  * |                   | due to conflict      |                             |
337  * |------------------------------------------------------------------------|
338  */
339 enum {
340 	NFSD4_ACTIVE = 0,
341 	NFSD4_COURTESY,
342 	NFSD4_EXPIRABLE,
343 };
344 
345 /*
346  * struct nfs4_client - one per client.  Clientids live here.
347  *
348  * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0)
349  * or EXCHANGE_ID (for NFSv4.1+). These objects are refcounted and timestamped.
350  * Each nfsd_net_ns object contains a set of these and they are tracked via
351  * short and long form clientid. They are hashed and searched for under the
352  * per-nfsd_net client_lock spinlock.
353  *
354  * References to it are only held during the processing of compounds, and in
355  * certain other operations. In their "resting state" they have a refcount of
356  * 0. If they are not renewed within a lease period, they become eligible for
357  * destruction by the laundromat.
358  *
359  * These objects can also be destroyed if the client sends certain forms of
360  * SETCLIENTID or EXCHANGE_ID operations.
361  *
362  * Care is taken *not* to do this however when the objects have an elevated
363  * refcount.
364  *
365  * o Each nfs4_client is hashed by clientid
366  *
367  * o Each nfs4_clients is also hashed by name (the opaque quantity initially
368  *   sent by the client to identify itself).
369  *
370  * o cl_perclient list is used to ensure no dangling stateowner references
371  *   when we expire the nfs4_client
372  */
373 struct nfs4_client {
374 	struct list_head	cl_idhash; 	/* hash by cl_clientid.id */
375 	struct rb_node		cl_namenode;	/* link into by-name trees */
376 	struct list_head	*cl_ownerstr_hashtbl;
377 	struct list_head	cl_openowners;
378 	struct idr		cl_stateids;	/* stateid lookup */
379 	struct list_head	cl_delegations;
380 	struct list_head	cl_revoked;	/* unacknowledged, revoked 4.1 state */
381 	struct list_head        cl_lru;         /* tail queue */
382 #ifdef CONFIG_NFSD_PNFS
383 	struct list_head	cl_lo_states;	/* outstanding layout states */
384 #endif
385 	struct xdr_netobj	cl_name; 	/* id generated by client */
386 	nfs4_verifier		cl_verifier; 	/* generated by client */
387 	time64_t		cl_time;	/* time of last lease renewal */
388 	struct sockaddr_storage	cl_addr; 	/* client ipaddress */
389 	bool			cl_mach_cred;	/* SP4_MACH_CRED in force */
390 	struct svc_cred		cl_cred; 	/* setclientid principal */
391 	clientid_t		cl_clientid;	/* generated by server */
392 	nfs4_verifier		cl_confirm;	/* generated by server */
393 	u32			cl_minorversion;
394 	atomic_t		cl_admin_revoked; /* count of admin-revoked states */
395 	/* NFSv4.1 client implementation id: */
396 	struct xdr_netobj	cl_nii_domain;
397 	struct xdr_netobj	cl_nii_name;
398 	struct timespec64	cl_nii_time;
399 
400 	/* for v4.0 and v4.1 callbacks: */
401 	struct nfs4_cb_conn	cl_cb_conn;
402 #define NFSD4_CLIENT_CB_UPDATE		(0)
403 #define NFSD4_CLIENT_CB_KILL		(1)
404 #define NFSD4_CLIENT_STABLE		(2)	/* client on stable storage */
405 #define NFSD4_CLIENT_RECLAIM_COMPLETE	(3)	/* reclaim_complete done */
406 #define NFSD4_CLIENT_CONFIRMED		(4)	/* client is confirmed */
407 #define NFSD4_CLIENT_UPCALL_LOCK	(5)	/* upcall serialization */
408 #define NFSD4_CLIENT_CB_FLAG_MASK	(1 << NFSD4_CLIENT_CB_UPDATE | \
409 					 1 << NFSD4_CLIENT_CB_KILL)
410 #define NFSD4_CLIENT_CB_RECALL_ANY	(6)
411 	unsigned long		cl_flags;
412 
413 	struct workqueue_struct *cl_callback_wq;
414 	const struct cred	*cl_cb_cred;
415 	struct rpc_clnt		*cl_cb_client;
416 	u32			cl_cb_ident;
417 #define NFSD4_CB_UP		0
418 #define NFSD4_CB_UNKNOWN	1
419 #define NFSD4_CB_DOWN		2
420 #define NFSD4_CB_FAULT		3
421 	int			cl_cb_state;
422 	struct nfsd4_callback	cl_cb_null;
423 	struct nfsd4_session	*cl_cb_session;
424 
425 	/* for all client information that callback code might need: */
426 	spinlock_t		cl_lock;
427 
428 	/* for nfs41 */
429 	struct list_head	cl_sessions;
430 	struct nfsd4_clid_slot	cl_cs_slot;	/* create_session slot */
431 	u32			cl_exchange_flags;
432 	/* number of rpc's in progress over an associated session: */
433 	atomic_t		cl_rpc_users;
434 	struct nfsdfs_client	cl_nfsdfs;
435 	struct nfs4_op_map      cl_spo_must_allow;
436 
437 	/* debugging info directory under nfsd/clients/ : */
438 	struct dentry		*cl_nfsd_dentry;
439 	/* 'info' file within that directory. Ref is not counted,
440 	 * but will remain valid iff cl_nfsd_dentry != NULL
441 	 */
442 	struct dentry		*cl_nfsd_info_dentry;
443 
444 	/* for nfs41 callbacks */
445 	/* We currently support a single back channel with a single slot */
446 	unsigned long		cl_cb_slot_busy;
447 	struct rpc_wait_queue	cl_cb_waitq;	/* backchannel callers may */
448 						/* wait here for slots */
449 	struct net		*net;
450 	struct list_head	async_copies;	/* list of async copies */
451 	spinlock_t		async_lock;	/* lock for async copies */
452 	atomic_t		cl_cb_inflight;	/* Outstanding callbacks */
453 
454 	unsigned int		cl_state;
455 	atomic_t		cl_delegs_in_recall;
456 
457 	struct nfsd4_cb_recall_any	*cl_ra;
458 	time64_t		cl_ra_time;
459 	struct list_head	cl_ra_cblist;
460 };
461 
462 /* struct nfs4_client_reset
463  * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
464  * upon lease reset, or from upcall to state_daemon (to read in state
465  * from non-volitile storage) upon reboot.
466  */
467 struct nfs4_client_reclaim {
468 	struct list_head	cr_strhash;	/* hash by cr_name */
469 	struct nfs4_client	*cr_clp;	/* pointer to associated clp */
470 	struct xdr_netobj	cr_name;	/* recovery dir name */
471 	struct xdr_netobj	cr_princhash;
472 };
473 
474 /* A reasonable value for REPLAY_ISIZE was estimated as follows:
475  * The OPEN response, typically the largest, requires
476  *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) +
477  *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) +
478  *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes
479  */
480 
481 #define NFSD4_REPLAY_ISIZE       112
482 
483 /*
484  * Replay buffer, where the result of the last seqid-mutating operation
485  * is cached.
486  */
487 struct nfs4_replay {
488 	__be32			rp_status;
489 	unsigned int		rp_buflen;
490 	char			*rp_buf;
491 	struct knfsd_fh		rp_openfh;
492 	atomic_t		rp_locked;
493 	char			rp_ibuf[NFSD4_REPLAY_ISIZE];
494 };
495 
496 struct nfs4_stateowner;
497 
498 struct nfs4_stateowner_operations {
499 	void (*so_unhash)(struct nfs4_stateowner *);
500 	void (*so_free)(struct nfs4_stateowner *);
501 };
502 
503 /*
504  * A core object that represents either an open or lock owner. The object and
505  * lock owner objects have one of these embedded within them. Refcounts and
506  * other fields common to both owner types are contained within these
507  * structures.
508  */
509 struct nfs4_stateowner {
510 	struct list_head			so_strhash;
511 	struct list_head			so_stateids;
512 	struct nfs4_client			*so_client;
513 	const struct nfs4_stateowner_operations	*so_ops;
514 	/* after increment in nfsd4_bump_seqid, represents the next
515 	 * sequence id expected from the client: */
516 	atomic_t				so_count;
517 	u32					so_seqid;
518 	struct xdr_netobj			so_owner; /* open owner name */
519 	struct nfs4_replay			so_replay;
520 	bool					so_is_open_owner;
521 };
522 
523 /*
524  * When a file is opened, the client provides an open state owner opaque string
525  * that indicates the "owner" of that open. These objects are refcounted.
526  * References to it are held by each open state associated with it. This object
527  * is a superset of the nfs4_stateowner struct.
528  */
529 struct nfs4_openowner {
530 	struct nfs4_stateowner	oo_owner; /* must be first field */
531 	struct list_head        oo_perclient;
532 	/*
533 	 * We keep around openowners a little while after last close,
534 	 * which saves clients from having to confirm, and allows us to
535 	 * handle close replays if they come soon enough.  The close_lru
536 	 * is a list of such openowners, to be reaped by the laundromat
537 	 * thread eventually if they remain unused:
538 	 */
539 	struct list_head	oo_close_lru;
540 	struct nfs4_ol_stateid *oo_last_closed_stid;
541 	time64_t		oo_time; /* time of placement on so_close_lru */
542 #define NFS4_OO_CONFIRMED   1
543 	unsigned char		oo_flags;
544 };
545 
546 /*
547  * Represents a generic "lockowner". Similar to an openowner. References to it
548  * are held by the lock stateids that are created on its behalf. This object is
549  * a superset of the nfs4_stateowner struct.
550  */
551 struct nfs4_lockowner {
552 	struct nfs4_stateowner	lo_owner;	/* must be first element */
553 	struct list_head	lo_blocked;	/* blocked file_locks */
554 };
555 
556 static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
557 {
558 	return container_of(so, struct nfs4_openowner, oo_owner);
559 }
560 
561 static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
562 {
563 	return container_of(so, struct nfs4_lockowner, lo_owner);
564 }
565 
566 /*
567  * Per-client state indicating no. of opens and outstanding delegations
568  * on a file from a particular client.'od' stands for 'open & delegation'
569  */
570 struct nfs4_clnt_odstate {
571 	struct nfs4_client	*co_client;
572 	struct nfs4_file	*co_file;
573 	struct list_head	co_perfile;
574 	refcount_t		co_odcount;
575 };
576 
577 /*
578  * nfs4_file: a file opened by some number of (open) nfs4_stateowners.
579  *
580  * These objects are global. nfsd keeps one instance of a nfs4_file per
581  * filehandle (though it may keep multiple file descriptors for each). Each
582  * inode can have multiple filehandles associated with it, so there is
583  * (potentially) a many to one relationship between this struct and struct
584  * inode.
585  */
586 struct nfs4_file {
587 	refcount_t		fi_ref;
588 	struct inode *		fi_inode;
589 	bool			fi_aliased;
590 	spinlock_t		fi_lock;
591 	struct rhlist_head	fi_rlist;
592 	struct list_head        fi_stateids;
593 	union {
594 		struct list_head	fi_delegations;
595 		struct rcu_head		fi_rcu;
596 	};
597 	struct list_head	fi_clnt_odstate;
598 	/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
599 	struct nfsd_file	*fi_fds[3];
600 	/*
601 	 * Each open or lock stateid contributes 0-4 to the counts
602 	 * below depending on which bits are set in st_access_bitmap:
603 	 *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
604 	 *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
605 	 *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
606 	 */
607 	atomic_t		fi_access[2];
608 	u32			fi_share_deny;
609 	struct nfsd_file	*fi_deleg_file;
610 	int			fi_delegees;
611 	struct knfsd_fh		fi_fhandle;
612 	bool			fi_had_conflict;
613 #ifdef CONFIG_NFSD_PNFS
614 	struct list_head	fi_lo_states;
615 	atomic_t		fi_lo_recalls;
616 #endif
617 };
618 
619 /*
620  * A generic struct representing either a open or lock stateid. The nfs4_client
621  * holds a reference to each of these objects, and they in turn hold a
622  * reference to their respective stateowners. The client's reference is
623  * released in response to a close or unlock (depending on whether it's an open
624  * or lock stateid) or when the client is being destroyed.
625  *
626  * In the case of v4.0 open stateids, these objects are preserved for a little
627  * while after close in order to handle CLOSE replays. Those are eventually
628  * reclaimed via a LRU scheme by the laundromat.
629  *
630  * This object is a superset of the nfs4_stid. "ol" stands for "Open or Lock".
631  * Better suggestions welcome.
632  */
633 struct nfs4_ol_stateid {
634 	struct nfs4_stid		st_stid;
635 	struct list_head		st_perfile;
636 	struct list_head		st_perstateowner;
637 	struct list_head		st_locks;
638 	struct nfs4_stateowner		*st_stateowner;
639 	struct nfs4_clnt_odstate	*st_clnt_odstate;
640 /*
641  * These bitmasks use 3 separate bits for READ, ALLOW, and BOTH; see the
642  * comment above bmap_to_share_mode() for explanation:
643  */
644 	unsigned char			st_access_bmap;
645 	unsigned char			st_deny_bmap;
646 	struct nfs4_ol_stateid		*st_openstp;
647 	struct mutex			st_mutex;
648 };
649 
650 static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
651 {
652 	return container_of(s, struct nfs4_ol_stateid, st_stid);
653 }
654 
655 struct nfs4_layout_stateid {
656 	struct nfs4_stid		ls_stid;
657 	struct list_head		ls_perclnt;
658 	struct list_head		ls_perfile;
659 	spinlock_t			ls_lock;
660 	struct list_head		ls_layouts;
661 	u32				ls_layout_type;
662 	struct nfsd_file		*ls_file;
663 	struct nfsd4_callback		ls_recall;
664 	stateid_t			ls_recall_sid;
665 	bool				ls_recalled;
666 	struct mutex			ls_mutex;
667 };
668 
669 static inline struct nfs4_layout_stateid *layoutstateid(struct nfs4_stid *s)
670 {
671 	return container_of(s, struct nfs4_layout_stateid, ls_stid);
672 }
673 
674 /* flags for preprocess_seqid_op() */
675 #define RD_STATE	        0x00000010
676 #define WR_STATE	        0x00000020
677 
678 enum nfsd4_cb_op {
679 	NFSPROC4_CLNT_CB_NULL = 0,
680 	NFSPROC4_CLNT_CB_RECALL,
681 	NFSPROC4_CLNT_CB_LAYOUT,
682 	NFSPROC4_CLNT_CB_OFFLOAD,
683 	NFSPROC4_CLNT_CB_SEQUENCE,
684 	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
685 	NFSPROC4_CLNT_CB_RECALL_ANY,
686 	NFSPROC4_CLNT_CB_GETATTR,
687 };
688 
689 /* Returns true iff a is later than b: */
690 static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
691 {
692 	return (s32)(a->si_generation - b->si_generation) > 0;
693 }
694 
695 /*
696  * When a client tries to get a lock on a file, we set one of these objects
697  * on the blocking lock. When the lock becomes free, we can then issue a
698  * CB_NOTIFY_LOCK to the server.
699  */
700 struct nfsd4_blocked_lock {
701 	struct list_head	nbl_list;
702 	struct list_head	nbl_lru;
703 	time64_t		nbl_time;
704 	struct file_lock	nbl_lock;
705 	struct knfsd_fh		nbl_fh;
706 	struct nfsd4_callback	nbl_cb;
707 	struct kref		nbl_kref;
708 };
709 
710 struct nfsd4_compound_state;
711 struct nfsd_net;
712 struct nfsd4_copy;
713 
714 extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
715 		struct nfsd4_compound_state *cstate, struct svc_fh *fhp,
716 		stateid_t *stateid, int flags, struct nfsd_file **filp,
717 		struct nfs4_stid **cstid);
718 __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
719 			    stateid_t *stateid, unsigned short typemask,
720 			    unsigned short statusmask,
721 			    struct nfs4_stid **s, struct nfsd_net *nn);
722 struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
723 				  void (*sc_free)(struct nfs4_stid *));
724 int nfs4_init_copy_state(struct nfsd_net *nn, struct nfsd4_copy *copy);
725 void nfs4_free_copy_state(struct nfsd4_copy *copy);
726 struct nfs4_cpntf_state *nfs4_alloc_init_cpntf_state(struct nfsd_net *nn,
727 			struct nfs4_stid *p_stid);
728 void nfs4_put_stid(struct nfs4_stid *s);
729 void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
730 void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
731 extern void nfs4_release_reclaim(struct nfsd_net *);
732 extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(struct xdr_netobj name,
733 							struct nfsd_net *nn);
734 extern __be32 nfs4_check_open_reclaim(struct nfs4_client *);
735 extern void nfsd4_probe_callback(struct nfs4_client *clp);
736 extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
737 extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
738 extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
739 		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
740 extern bool nfsd4_run_cb(struct nfsd4_callback *cb);
741 extern void nfsd4_shutdown_callback(struct nfs4_client *);
742 extern void nfsd4_shutdown_copy(struct nfs4_client *clp);
743 extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(struct xdr_netobj name,
744 				struct xdr_netobj princhash, struct nfsd_net *nn);
745 extern bool nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn);
746 
747 void put_nfs4_file(struct nfs4_file *fi);
748 extern void nfs4_put_cpntf_state(struct nfsd_net *nn,
749 				 struct nfs4_cpntf_state *cps);
750 extern __be32 manage_cpntf_state(struct nfsd_net *nn, stateid_t *st,
751 				 struct nfs4_client *clp,
752 				 struct nfs4_cpntf_state **cps);
753 static inline void get_nfs4_file(struct nfs4_file *fi)
754 {
755 	refcount_inc(&fi->fi_ref);
756 }
757 struct nfsd_file *find_any_file(struct nfs4_file *f);
758 
759 #ifdef CONFIG_NFSD_V4
760 void nfsd4_revoke_states(struct net *net, struct super_block *sb);
761 #else
762 static inline void nfsd4_revoke_states(struct net *net, struct super_block *sb)
763 {
764 }
765 #endif
766 
767 /* grace period management */
768 void nfsd4_end_grace(struct nfsd_net *nn);
769 
770 /* nfs4recover operations */
771 extern int nfsd4_client_tracking_init(struct net *net);
772 extern void nfsd4_client_tracking_exit(struct net *net);
773 extern void nfsd4_client_record_create(struct nfs4_client *clp);
774 extern void nfsd4_client_record_remove(struct nfs4_client *clp);
775 extern int nfsd4_client_record_check(struct nfs4_client *clp);
776 extern void nfsd4_record_grace_done(struct nfsd_net *nn);
777 
778 static inline bool try_to_expire_client(struct nfs4_client *clp)
779 {
780 	cmpxchg(&clp->cl_state, NFSD4_COURTESY, NFSD4_EXPIRABLE);
781 	return clp->cl_state == NFSD4_EXPIRABLE;
782 }
783 
784 extern __be32 nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp,
785 		struct dentry *dentry, bool *file_modified, u64 *size);
786 #endif   /* NFSD4_STATE_H */
787