xref: /linux/fs/nfsd/state.h (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
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 
92 	/* A new stateid is added to the cl_stateids idr early before it
93 	 * is fully initialised.  Its sc_type is then zero.  After
94 	 * initialisation the sc_type it set under cl_lock, and then
95 	 * never changes.
96 	 */
97 #define SC_TYPE_OPEN		BIT(0)
98 #define SC_TYPE_LOCK		BIT(1)
99 #define SC_TYPE_DELEG		BIT(2)
100 #define SC_TYPE_LAYOUT		BIT(3)
101 	unsigned short		sc_type;
102 
103 /* state_lock protects sc_status for delegation stateids.
104  * ->cl_lock protects sc_status for open and lock stateids.
105  * ->st_mutex also protect sc_status for open stateids.
106  * ->ls_lock protects sc_status for layout stateids.
107  */
108 /*
109  * For an open stateid kept around *only* to process close replays.
110  * For deleg stateid, kept in idr until last reference is dropped.
111  */
112 #define SC_STATUS_CLOSED	BIT(0)
113 /* For a deleg stateid kept around only to process free_stateid's: */
114 #define SC_STATUS_REVOKED	BIT(1)
115 #define SC_STATUS_ADMIN_REVOKED	BIT(2)
116 	unsigned short		sc_status;
117 
118 	struct list_head	sc_cp_list;
119 	stateid_t		sc_stateid;
120 	spinlock_t		sc_lock;
121 	struct nfs4_client	*sc_client;
122 	struct nfs4_file	*sc_file;
123 	void			(*sc_free)(struct nfs4_stid *);
124 };
125 
126 /* Keep a list of stateids issued by the COPY_NOTIFY, associate it with the
127  * parent OPEN/LOCK/DELEG stateid.
128  */
129 struct nfs4_cpntf_state {
130 	copy_stateid_t		cp_stateid;
131 	struct list_head	cp_list;	/* per parent nfs4_stid */
132 	stateid_t		cp_p_stateid;	/* copy of parent's stateid */
133 	clientid_t		cp_p_clid;	/* copy of parent's clid */
134 	time64_t		cpntf_time;	/* last time stateid used */
135 };
136 
137 struct nfs4_cb_fattr {
138 	struct nfsd4_callback ncf_getattr;
139 	u32 ncf_cb_status;
140 	u32 ncf_cb_bmap[1];
141 
142 	/* from CB_GETATTR reply */
143 	u64 ncf_cb_change;
144 	u64 ncf_cb_fsize;
145 
146 	unsigned long ncf_cb_flags;
147 	bool ncf_file_modified;
148 	u64 ncf_initial_cinfo;
149 	u64 ncf_cur_fsize;
150 };
151 
152 /* bits for ncf_cb_flags */
153 #define	CB_GETATTR_BUSY		0
154 
155 /*
156  * Represents a delegation stateid. The nfs4_client holds references to these
157  * and they are put when it is being destroyed or when the delegation is
158  * returned by the client:
159  *
160  * o 1 reference as long as a delegation is still in force (taken when it's
161  *   alloc'd, put when it's returned or revoked)
162  *
163  * o 1 reference as long as a recall rpc is in progress (taken when the lease
164  *   is broken, put when the rpc exits)
165  *
166  * o 1 more ephemeral reference for each nfsd thread currently doing something
167  *   with that delegation without holding the cl_lock
168  *
169  * If the server attempts to recall a delegation and the client doesn't do so
170  * before a timeout, the server may also revoke the delegation. In that case,
171  * the object will either be destroyed (v4.0) or moved to a per-client list of
172  * revoked delegations (v4.1+).
173  *
174  * This object is a superset of the nfs4_stid.
175  */
176 struct nfs4_delegation {
177 	struct nfs4_stid	dl_stid; /* must be first field */
178 	struct list_head	dl_perfile;
179 	struct list_head	dl_perclnt;
180 	struct list_head	dl_recall_lru;  /* delegation recalled */
181 	struct nfs4_clnt_odstate *dl_clnt_odstate;
182 	u32			dl_type;
183 	time64_t		dl_time;
184 /* For recall: */
185 	int			dl_retries;
186 	struct nfsd4_callback	dl_recall;
187 	bool			dl_recalled;
188 
189 	/* for CB_GETATTR */
190 	struct nfs4_cb_fattr    dl_cb_fattr;
191 };
192 
193 #define cb_to_delegation(cb) \
194 	container_of(cb, struct nfs4_delegation, dl_recall)
195 
196 /* client delegation callback info */
197 struct nfs4_cb_conn {
198 	/* SETCLIENTID info */
199 	struct sockaddr_storage	cb_addr;
200 	struct sockaddr_storage	cb_saddr;
201 	size_t			cb_addrlen;
202 	u32                     cb_prog; /* used only in 4.0 case;
203 					    per-session otherwise */
204 	u32                     cb_ident;	/* minorversion 0 only */
205 	struct svc_xprt		*cb_xprt;	/* minorversion 1 only */
206 };
207 
208 static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
209 {
210 	return container_of(s, struct nfs4_delegation, dl_stid);
211 }
212 
213 /* Maximum number of slots per session. 160 is useful for long haul TCP */
214 #define NFSD_MAX_SLOTS_PER_SESSION     160
215 /* Maximum  session per slot cache size */
216 #define NFSD_SLOT_CACHE_SIZE		2048
217 /* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
218 #define NFSD_CACHE_SIZE_SLOTS_PER_SESSION	32
219 #define NFSD_MAX_MEM_PER_SESSION  \
220 		(NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
221 
222 struct nfsd4_slot {
223 	u32	sl_seqid;
224 	__be32	sl_status;
225 	struct svc_cred sl_cred;
226 	u32	sl_datalen;
227 	u16	sl_opcnt;
228 #define NFSD4_SLOT_INUSE	(1 << 0)
229 #define NFSD4_SLOT_CACHETHIS	(1 << 1)
230 #define NFSD4_SLOT_INITIALIZED	(1 << 2)
231 #define NFSD4_SLOT_CACHED	(1 << 3)
232 	u8	sl_flags;
233 	char	sl_data[];
234 };
235 
236 struct nfsd4_channel_attrs {
237 	u32		headerpadsz;
238 	u32		maxreq_sz;
239 	u32		maxresp_sz;
240 	u32		maxresp_cached;
241 	u32		maxops;
242 	u32		maxreqs;
243 	u32		nr_rdma_attrs;
244 	u32		rdma_attrs;
245 };
246 
247 struct nfsd4_cb_sec {
248 	u32	flavor; /* (u32)(-1) used to mean "no valid flavor" */
249 	kuid_t	uid;
250 	kgid_t	gid;
251 };
252 
253 struct nfsd4_create_session {
254 	clientid_t			clientid;
255 	struct nfs4_sessionid		sessionid;
256 	u32				seqid;
257 	u32				flags;
258 	struct nfsd4_channel_attrs	fore_channel;
259 	struct nfsd4_channel_attrs	back_channel;
260 	u32				callback_prog;
261 	struct nfsd4_cb_sec		cb_sec;
262 };
263 
264 struct nfsd4_backchannel_ctl {
265 	u32	bc_cb_program;
266 	struct nfsd4_cb_sec		bc_cb_sec;
267 };
268 
269 struct nfsd4_bind_conn_to_session {
270 	struct nfs4_sessionid		sessionid;
271 	u32				dir;
272 };
273 
274 /* The single slot clientid cache structure */
275 struct nfsd4_clid_slot {
276 	u32				sl_seqid;
277 	__be32				sl_status;
278 	struct nfsd4_create_session	sl_cr_ses;
279 };
280 
281 struct nfsd4_conn {
282 	struct list_head cn_persession;
283 	struct svc_xprt *cn_xprt;
284 	struct svc_xpt_user cn_xpt_user;
285 	struct nfsd4_session *cn_session;
286 /* CDFC4_FORE, CDFC4_BACK: */
287 	unsigned char cn_flags;
288 };
289 
290 /*
291  * Representation of a v4.1+ session. These are refcounted in a similar fashion
292  * to the nfs4_client. References are only taken when the server is actively
293  * working on the object (primarily during the processing of compounds).
294  */
295 struct nfsd4_session {
296 	atomic_t		se_ref;
297 	struct list_head	se_hash;	/* hash by sessionid */
298 	struct list_head	se_perclnt;
299 /* See SESSION4_PERSIST, etc. for standard flags; this is internal-only: */
300 #define NFS4_SESSION_DEAD	0x010
301 	u32			se_flags;
302 	struct nfs4_client	*se_client;
303 	struct nfs4_sessionid	se_sessionid;
304 	struct nfsd4_channel_attrs se_fchannel;
305 	struct nfsd4_channel_attrs se_bchannel;
306 	struct nfsd4_cb_sec	se_cb_sec;
307 	struct list_head	se_conns;
308 	u32			se_cb_prog;
309 	u32			se_cb_seq_nr;
310 	struct nfsd4_slot	*se_slots[];	/* forward channel slots */
311 };
312 
313 /* formatted contents of nfs4_sessionid */
314 struct nfsd4_sessionid {
315 	clientid_t	clientid;
316 	u32		sequence;
317 	u32		reserved;
318 };
319 
320 #define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
321 
322 /*
323  *       State                Meaning                  Where set
324  * --------------------------------------------------------------------------
325  * | NFSD4_ACTIVE      | Confirmed, active    | Default                     |
326  * |------------------- ----------------------------------------------------|
327  * | NFSD4_COURTESY    | Courtesy state.      | nfs4_get_client_reaplist    |
328  * |                   | Lease/lock/share     |                             |
329  * |                   | reservation conflict |                             |
330  * |                   | can cause Courtesy   |                             |
331  * |                   | client to be expired |                             |
332  * |------------------------------------------------------------------------|
333  * | NFSD4_EXPIRABLE   | Courtesy client to be| nfs4_laundromat             |
334  * |                   | expired by Laundromat| try_to_expire_client        |
335  * |                   | due to conflict      |                             |
336  * |------------------------------------------------------------------------|
337  */
338 enum {
339 	NFSD4_ACTIVE = 0,
340 	NFSD4_COURTESY,
341 	NFSD4_EXPIRABLE,
342 };
343 
344 /*
345  * struct nfs4_client - one per client.  Clientids live here.
346  *
347  * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0)
348  * or EXCHANGE_ID (for NFSv4.1+). These objects are refcounted and timestamped.
349  * Each nfsd_net_ns object contains a set of these and they are tracked via
350  * short and long form clientid. They are hashed and searched for under the
351  * per-nfsd_net client_lock spinlock.
352  *
353  * References to it are only held during the processing of compounds, and in
354  * certain other operations. In their "resting state" they have a refcount of
355  * 0. If they are not renewed within a lease period, they become eligible for
356  * destruction by the laundromat.
357  *
358  * These objects can also be destroyed if the client sends certain forms of
359  * SETCLIENTID or EXCHANGE_ID operations.
360  *
361  * Care is taken *not* to do this however when the objects have an elevated
362  * refcount.
363  *
364  * o Each nfs4_client is hashed by clientid
365  *
366  * o Each nfs4_clients is also hashed by name (the opaque quantity initially
367  *   sent by the client to identify itself).
368  *
369  * o cl_perclient list is used to ensure no dangling stateowner references
370  *   when we expire the nfs4_client
371  */
372 struct nfs4_client {
373 	struct list_head	cl_idhash; 	/* hash by cl_clientid.id */
374 	struct rb_node		cl_namenode;	/* link into by-name trees */
375 	struct list_head	*cl_ownerstr_hashtbl;
376 	struct list_head	cl_openowners;
377 	struct idr		cl_stateids;	/* stateid lookup */
378 	struct list_head	cl_delegations;
379 	struct list_head	cl_revoked;	/* unacknowledged, revoked 4.1 state */
380 	struct list_head        cl_lru;         /* tail queue */
381 #ifdef CONFIG_NFSD_PNFS
382 	struct list_head	cl_lo_states;	/* outstanding layout states */
383 #endif
384 	struct xdr_netobj	cl_name; 	/* id generated by client */
385 	nfs4_verifier		cl_verifier; 	/* generated by client */
386 	time64_t		cl_time;	/* time of last lease renewal */
387 	struct sockaddr_storage	cl_addr; 	/* client ipaddress */
388 	bool			cl_mach_cred;	/* SP4_MACH_CRED in force */
389 	struct svc_cred		cl_cred; 	/* setclientid principal */
390 	clientid_t		cl_clientid;	/* generated by server */
391 	nfs4_verifier		cl_confirm;	/* generated by server */
392 	u32			cl_minorversion;
393 	atomic_t		cl_admin_revoked; /* count of admin-revoked states */
394 	/* NFSv4.1 client implementation id: */
395 	struct xdr_netobj	cl_nii_domain;
396 	struct xdr_netobj	cl_nii_name;
397 	struct timespec64	cl_nii_time;
398 
399 	/* for v4.0 and v4.1 callbacks: */
400 	struct nfs4_cb_conn	cl_cb_conn;
401 #define NFSD4_CLIENT_CB_UPDATE		(0)
402 #define NFSD4_CLIENT_CB_KILL		(1)
403 #define NFSD4_CLIENT_STABLE		(2)	/* client on stable storage */
404 #define NFSD4_CLIENT_RECLAIM_COMPLETE	(3)	/* reclaim_complete done */
405 #define NFSD4_CLIENT_CONFIRMED		(4)	/* client is confirmed */
406 #define NFSD4_CLIENT_UPCALL_LOCK	(5)	/* upcall serialization */
407 #define NFSD4_CLIENT_CB_FLAG_MASK	(1 << NFSD4_CLIENT_CB_UPDATE | \
408 					 1 << NFSD4_CLIENT_CB_KILL)
409 #define NFSD4_CLIENT_CB_RECALL_ANY	(6)
410 	unsigned long		cl_flags;
411 
412 	struct workqueue_struct *cl_callback_wq;
413 	const struct cred	*cl_cb_cred;
414 	struct rpc_clnt		*cl_cb_client;
415 	u32			cl_cb_ident;
416 #define NFSD4_CB_UP		0
417 #define NFSD4_CB_UNKNOWN	1
418 #define NFSD4_CB_DOWN		2
419 #define NFSD4_CB_FAULT		3
420 	int			cl_cb_state;
421 	struct nfsd4_callback	cl_cb_null;
422 	struct nfsd4_session	*cl_cb_session;
423 
424 	/* for all client information that callback code might need: */
425 	spinlock_t		cl_lock;
426 
427 	/* for nfs41 */
428 	struct list_head	cl_sessions;
429 	struct nfsd4_clid_slot	cl_cs_slot;	/* create_session slot */
430 	u32			cl_exchange_flags;
431 	/* number of rpc's in progress over an associated session: */
432 	atomic_t		cl_rpc_users;
433 	struct nfsdfs_client	cl_nfsdfs;
434 	struct nfs4_op_map      cl_spo_must_allow;
435 
436 	/* debugging info directory under nfsd/clients/ : */
437 	struct dentry		*cl_nfsd_dentry;
438 	/* 'info' file within that directory. Ref is not counted,
439 	 * but will remain valid iff cl_nfsd_dentry != NULL
440 	 */
441 	struct dentry		*cl_nfsd_info_dentry;
442 
443 	/* for nfs41 callbacks */
444 	/* We currently support a single back channel with a single slot */
445 	unsigned long		cl_cb_slot_busy;
446 	struct rpc_wait_queue	cl_cb_waitq;	/* backchannel callers may */
447 						/* wait here for slots */
448 	struct net		*net;
449 	struct list_head	async_copies;	/* list of async copies */
450 	spinlock_t		async_lock;	/* lock for async copies */
451 	atomic_t		cl_cb_inflight;	/* Outstanding callbacks */
452 
453 	unsigned int		cl_state;
454 	atomic_t		cl_delegs_in_recall;
455 
456 	struct nfsd4_cb_recall_any	*cl_ra;
457 	time64_t		cl_ra_time;
458 	struct list_head	cl_ra_cblist;
459 };
460 
461 /* struct nfs4_client_reset
462  * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
463  * upon lease reset, or from upcall to state_daemon (to read in state
464  * from non-volitile storage) upon reboot.
465  */
466 struct nfs4_client_reclaim {
467 	struct list_head	cr_strhash;	/* hash by cr_name */
468 	struct nfs4_client	*cr_clp;	/* pointer to associated clp */
469 	struct xdr_netobj	cr_name;	/* recovery dir name */
470 	struct xdr_netobj	cr_princhash;
471 };
472 
473 /* A reasonable value for REPLAY_ISIZE was estimated as follows:
474  * The OPEN response, typically the largest, requires
475  *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) +
476  *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) +
477  *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes
478  */
479 
480 #define NFSD4_REPLAY_ISIZE       112
481 
482 /*
483  * Replay buffer, where the result of the last seqid-mutating operation
484  * is cached.
485  */
486 struct nfs4_replay {
487 	__be32			rp_status;
488 	unsigned int		rp_buflen;
489 	char			*rp_buf;
490 	struct knfsd_fh		rp_openfh;
491 	atomic_t		rp_locked;
492 	char			rp_ibuf[NFSD4_REPLAY_ISIZE];
493 };
494 
495 struct nfs4_stateowner;
496 
497 struct nfs4_stateowner_operations {
498 	void (*so_unhash)(struct nfs4_stateowner *);
499 	void (*so_free)(struct nfs4_stateowner *);
500 };
501 
502 /*
503  * A core object that represents either an open or lock owner. The object and
504  * lock owner objects have one of these embedded within them. Refcounts and
505  * other fields common to both owner types are contained within these
506  * structures.
507  */
508 struct nfs4_stateowner {
509 	struct list_head			so_strhash;
510 	struct list_head			so_stateids;
511 	struct nfs4_client			*so_client;
512 	const struct nfs4_stateowner_operations	*so_ops;
513 	/* after increment in nfsd4_bump_seqid, represents the next
514 	 * sequence id expected from the client: */
515 	atomic_t				so_count;
516 	u32					so_seqid;
517 	struct xdr_netobj			so_owner; /* open owner name */
518 	struct nfs4_replay			so_replay;
519 	bool					so_is_open_owner;
520 };
521 
522 /*
523  * When a file is opened, the client provides an open state owner opaque string
524  * that indicates the "owner" of that open. These objects are refcounted.
525  * References to it are held by each open state associated with it. This object
526  * is a superset of the nfs4_stateowner struct.
527  */
528 struct nfs4_openowner {
529 	struct nfs4_stateowner	oo_owner; /* must be first field */
530 	struct list_head        oo_perclient;
531 	/*
532 	 * We keep around openowners a little while after last close,
533 	 * which saves clients from having to confirm, and allows us to
534 	 * handle close replays if they come soon enough.  The close_lru
535 	 * is a list of such openowners, to be reaped by the laundromat
536 	 * thread eventually if they remain unused:
537 	 */
538 	struct list_head	oo_close_lru;
539 	struct nfs4_ol_stateid *oo_last_closed_stid;
540 	time64_t		oo_time; /* time of placement on so_close_lru */
541 #define NFS4_OO_CONFIRMED   1
542 	unsigned char		oo_flags;
543 };
544 
545 /*
546  * Represents a generic "lockowner". Similar to an openowner. References to it
547  * are held by the lock stateids that are created on its behalf. This object is
548  * a superset of the nfs4_stateowner struct.
549  */
550 struct nfs4_lockowner {
551 	struct nfs4_stateowner	lo_owner;	/* must be first element */
552 	struct list_head	lo_blocked;	/* blocked file_locks */
553 };
554 
555 static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
556 {
557 	return container_of(so, struct nfs4_openowner, oo_owner);
558 }
559 
560 static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
561 {
562 	return container_of(so, struct nfs4_lockowner, lo_owner);
563 }
564 
565 /*
566  * Per-client state indicating no. of opens and outstanding delegations
567  * on a file from a particular client.'od' stands for 'open & delegation'
568  */
569 struct nfs4_clnt_odstate {
570 	struct nfs4_client	*co_client;
571 	struct nfs4_file	*co_file;
572 	struct list_head	co_perfile;
573 	refcount_t		co_odcount;
574 };
575 
576 /*
577  * nfs4_file: a file opened by some number of (open) nfs4_stateowners.
578  *
579  * These objects are global. nfsd keeps one instance of a nfs4_file per
580  * filehandle (though it may keep multiple file descriptors for each). Each
581  * inode can have multiple filehandles associated with it, so there is
582  * (potentially) a many to one relationship between this struct and struct
583  * inode.
584  */
585 struct nfs4_file {
586 	refcount_t		fi_ref;
587 	struct inode *		fi_inode;
588 	bool			fi_aliased;
589 	spinlock_t		fi_lock;
590 	struct rhlist_head	fi_rlist;
591 	struct list_head        fi_stateids;
592 	union {
593 		struct list_head	fi_delegations;
594 		struct rcu_head		fi_rcu;
595 	};
596 	struct list_head	fi_clnt_odstate;
597 	/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
598 	struct nfsd_file	*fi_fds[3];
599 	/*
600 	 * Each open or lock stateid contributes 0-4 to the counts
601 	 * below depending on which bits are set in st_access_bitmap:
602 	 *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
603 	 *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
604 	 *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
605 	 */
606 	atomic_t		fi_access[2];
607 	u32			fi_share_deny;
608 	struct nfsd_file	*fi_deleg_file;
609 	int			fi_delegees;
610 	struct knfsd_fh		fi_fhandle;
611 	bool			fi_had_conflict;
612 #ifdef CONFIG_NFSD_PNFS
613 	struct list_head	fi_lo_states;
614 	atomic_t		fi_lo_recalls;
615 #endif
616 };
617 
618 /*
619  * A generic struct representing either a open or lock stateid. The nfs4_client
620  * holds a reference to each of these objects, and they in turn hold a
621  * reference to their respective stateowners. The client's reference is
622  * released in response to a close or unlock (depending on whether it's an open
623  * or lock stateid) or when the client is being destroyed.
624  *
625  * In the case of v4.0 open stateids, these objects are preserved for a little
626  * while after close in order to handle CLOSE replays. Those are eventually
627  * reclaimed via a LRU scheme by the laundromat.
628  *
629  * This object is a superset of the nfs4_stid. "ol" stands for "Open or Lock".
630  * Better suggestions welcome.
631  */
632 struct nfs4_ol_stateid {
633 	struct nfs4_stid		st_stid;
634 	struct list_head		st_perfile;
635 	struct list_head		st_perstateowner;
636 	struct list_head		st_locks;
637 	struct nfs4_stateowner		*st_stateowner;
638 	struct nfs4_clnt_odstate	*st_clnt_odstate;
639 /*
640  * These bitmasks use 3 separate bits for READ, ALLOW, and BOTH; see the
641  * comment above bmap_to_share_mode() for explanation:
642  */
643 	unsigned char			st_access_bmap;
644 	unsigned char			st_deny_bmap;
645 	struct nfs4_ol_stateid		*st_openstp;
646 	struct mutex			st_mutex;
647 };
648 
649 static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
650 {
651 	return container_of(s, struct nfs4_ol_stateid, st_stid);
652 }
653 
654 struct nfs4_layout_stateid {
655 	struct nfs4_stid		ls_stid;
656 	struct list_head		ls_perclnt;
657 	struct list_head		ls_perfile;
658 	spinlock_t			ls_lock;
659 	struct list_head		ls_layouts;
660 	u32				ls_layout_type;
661 	struct nfsd_file		*ls_file;
662 	struct nfsd4_callback		ls_recall;
663 	stateid_t			ls_recall_sid;
664 	bool				ls_recalled;
665 	struct mutex			ls_mutex;
666 };
667 
668 static inline struct nfs4_layout_stateid *layoutstateid(struct nfs4_stid *s)
669 {
670 	return container_of(s, struct nfs4_layout_stateid, ls_stid);
671 }
672 
673 /* flags for preprocess_seqid_op() */
674 #define RD_STATE	        0x00000010
675 #define WR_STATE	        0x00000020
676 
677 enum nfsd4_cb_op {
678 	NFSPROC4_CLNT_CB_NULL = 0,
679 	NFSPROC4_CLNT_CB_RECALL,
680 	NFSPROC4_CLNT_CB_LAYOUT,
681 	NFSPROC4_CLNT_CB_OFFLOAD,
682 	NFSPROC4_CLNT_CB_SEQUENCE,
683 	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
684 	NFSPROC4_CLNT_CB_RECALL_ANY,
685 	NFSPROC4_CLNT_CB_GETATTR,
686 };
687 
688 /* Returns true iff a is later than b: */
689 static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
690 {
691 	return (s32)(a->si_generation - b->si_generation) > 0;
692 }
693 
694 /*
695  * When a client tries to get a lock on a file, we set one of these objects
696  * on the blocking lock. When the lock becomes free, we can then issue a
697  * CB_NOTIFY_LOCK to the server.
698  */
699 struct nfsd4_blocked_lock {
700 	struct list_head	nbl_list;
701 	struct list_head	nbl_lru;
702 	time64_t		nbl_time;
703 	struct file_lock	nbl_lock;
704 	struct knfsd_fh		nbl_fh;
705 	struct nfsd4_callback	nbl_cb;
706 	struct kref		nbl_kref;
707 };
708 
709 struct nfsd4_compound_state;
710 struct nfsd_net;
711 struct nfsd4_copy;
712 
713 extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
714 		struct nfsd4_compound_state *cstate, struct svc_fh *fhp,
715 		stateid_t *stateid, int flags, struct nfsd_file **filp,
716 		struct nfs4_stid **cstid);
717 __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
718 			    stateid_t *stateid, unsigned short typemask,
719 			    unsigned short statusmask,
720 			    struct nfs4_stid **s, struct nfsd_net *nn);
721 struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
722 				  void (*sc_free)(struct nfs4_stid *));
723 int nfs4_init_copy_state(struct nfsd_net *nn, struct nfsd4_copy *copy);
724 void nfs4_free_copy_state(struct nfsd4_copy *copy);
725 struct nfs4_cpntf_state *nfs4_alloc_init_cpntf_state(struct nfsd_net *nn,
726 			struct nfs4_stid *p_stid);
727 void nfs4_put_stid(struct nfs4_stid *s);
728 void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
729 void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
730 extern void nfs4_release_reclaim(struct nfsd_net *);
731 extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(struct xdr_netobj name,
732 							struct nfsd_net *nn);
733 extern __be32 nfs4_check_open_reclaim(struct nfs4_client *);
734 extern void nfsd4_probe_callback(struct nfs4_client *clp);
735 extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
736 extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
737 extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
738 		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
739 extern bool nfsd4_run_cb(struct nfsd4_callback *cb);
740 extern void nfsd4_shutdown_callback(struct nfs4_client *);
741 extern void nfsd4_shutdown_copy(struct nfs4_client *clp);
742 extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(struct xdr_netobj name,
743 				struct xdr_netobj princhash, struct nfsd_net *nn);
744 extern bool nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn);
745 
746 void put_nfs4_file(struct nfs4_file *fi);
747 extern void nfs4_put_cpntf_state(struct nfsd_net *nn,
748 				 struct nfs4_cpntf_state *cps);
749 extern __be32 manage_cpntf_state(struct nfsd_net *nn, stateid_t *st,
750 				 struct nfs4_client *clp,
751 				 struct nfs4_cpntf_state **cps);
752 static inline void get_nfs4_file(struct nfs4_file *fi)
753 {
754 	refcount_inc(&fi->fi_ref);
755 }
756 struct nfsd_file *find_any_file(struct nfs4_file *f);
757 
758 #ifdef CONFIG_NFSD_V4
759 void nfsd4_revoke_states(struct net *net, struct super_block *sb);
760 #else
761 static inline void nfsd4_revoke_states(struct net *net, struct super_block *sb)
762 {
763 }
764 #endif
765 
766 /* grace period management */
767 void nfsd4_end_grace(struct nfsd_net *nn);
768 
769 /* nfs4recover operations */
770 extern int nfsd4_client_tracking_init(struct net *net);
771 extern void nfsd4_client_tracking_exit(struct net *net);
772 extern void nfsd4_client_record_create(struct nfs4_client *clp);
773 extern void nfsd4_client_record_remove(struct nfs4_client *clp);
774 extern int nfsd4_client_record_check(struct nfs4_client *clp);
775 extern void nfsd4_record_grace_done(struct nfsd_net *nn);
776 
777 static inline bool try_to_expire_client(struct nfs4_client *clp)
778 {
779 	cmpxchg(&clp->cl_state, NFSD4_COURTESY, NFSD4_EXPIRABLE);
780 	return clp->cl_state == NFSD4_EXPIRABLE;
781 }
782 
783 extern __be32 nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp,
784 		struct dentry *dentry, bool *file_modified, u64 *size);
785 #endif   /* NFSD4_STATE_H */
786