xref: /linux/fs/nfsd/state.h (revision e31e3f6c0ce473f7ce1e70d54ac8e3ed190509f8)
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 	struct timespec64 ncf_cb_mtime;
163 	struct timespec64 ncf_cb_atime;
164 
165 	unsigned long ncf_cb_flags;
166 	bool ncf_file_modified;
167 	u64 ncf_initial_cinfo;
168 	u64 ncf_cur_fsize;
169 };
170 
171 /* bits for ncf_cb_flags */
172 #define	CB_GETATTR_BUSY		0
173 
174 /*
175  * Represents a delegation stateid. The nfs4_client holds references to these
176  * and they are put when it is being destroyed or when the delegation is
177  * returned by the client:
178  *
179  * o 1 reference as long as a delegation is still in force (taken when it's
180  *   alloc'd, put when it's returned or revoked)
181  *
182  * o 1 reference as long as a recall rpc is in progress (taken when the lease
183  *   is broken, put when the rpc exits)
184  *
185  * o 1 more ephemeral reference for each nfsd thread currently doing something
186  *   with that delegation without holding the cl_lock
187  *
188  * If the server attempts to recall a delegation and the client doesn't do so
189  * before a timeout, the server may also revoke the delegation. In that case,
190  * the object will either be destroyed (v4.0) or moved to a per-client list of
191  * revoked delegations (v4.1+).
192  *
193  * This object is a superset of the nfs4_stid.
194  */
195 struct nfs4_delegation {
196 	struct nfs4_stid	dl_stid; /* must be first field */
197 	struct list_head	dl_perfile;
198 	struct list_head	dl_perclnt;
199 	struct list_head	dl_recall_lru;  /* delegation recalled */
200 	struct nfs4_clnt_odstate *dl_clnt_odstate;
201 	u32			dl_type;
202 	time64_t		dl_time;
203 /* For recall: */
204 	int			dl_retries;
205 	struct nfsd4_callback	dl_recall;
206 	bool			dl_recalled;
207 
208 	/* for CB_GETATTR */
209 	struct nfs4_cb_fattr    dl_cb_fattr;
210 };
211 
212 static inline bool deleg_is_read(u32 dl_type)
213 {
214 	return (dl_type == OPEN_DELEGATE_READ || dl_type == OPEN_DELEGATE_READ_ATTRS_DELEG);
215 }
216 
217 static inline bool deleg_is_write(u32 dl_type)
218 {
219 	return (dl_type == OPEN_DELEGATE_WRITE || dl_type == OPEN_DELEGATE_WRITE_ATTRS_DELEG);
220 }
221 
222 static inline bool deleg_attrs_deleg(u32 dl_type)
223 {
224 	return dl_type == OPEN_DELEGATE_READ_ATTRS_DELEG ||
225 	       dl_type == OPEN_DELEGATE_WRITE_ATTRS_DELEG;
226 }
227 
228 #define cb_to_delegation(cb) \
229 	container_of(cb, struct nfs4_delegation, dl_recall)
230 
231 /* client delegation callback info */
232 struct nfs4_cb_conn {
233 	/* SETCLIENTID info */
234 	struct sockaddr_storage	cb_addr;
235 	struct sockaddr_storage	cb_saddr;
236 	size_t			cb_addrlen;
237 	u32                     cb_prog; /* used only in 4.0 case;
238 					    per-session otherwise */
239 	u32                     cb_ident;	/* minorversion 0 only */
240 	struct svc_xprt		*cb_xprt;	/* minorversion 1 only */
241 };
242 
243 static inline struct nfs4_delegation *delegstateid(struct nfs4_stid *s)
244 {
245 	return container_of(s, struct nfs4_delegation, dl_stid);
246 }
247 
248 /* Maximum number of slots per session.  This is for sanity-check only.
249  * It could be increased if we had a mechanism to shutdown misbehaving clients.
250  * A large number can be needed to get good throughput on high-latency servers.
251  */
252 #define NFSD_MAX_SLOTS_PER_SESSION	2048
253 /* Maximum  session per slot cache size */
254 #define NFSD_SLOT_CACHE_SIZE		2048
255 /* Maximum number of NFSD_SLOT_CACHE_SIZE slots per session */
256 #define NFSD_CACHE_SIZE_SLOTS_PER_SESSION	32
257 #define NFSD_MAX_MEM_PER_SESSION  \
258 		(NFSD_CACHE_SIZE_SLOTS_PER_SESSION * NFSD_SLOT_CACHE_SIZE)
259 
260 struct nfsd4_slot {
261 	u32	sl_seqid;
262 	__be32	sl_status;
263 	struct svc_cred sl_cred;
264 	u32	sl_datalen;
265 	u16	sl_opcnt;
266 	u16	sl_generation;
267 #define NFSD4_SLOT_INUSE	(1 << 0)
268 #define NFSD4_SLOT_CACHETHIS	(1 << 1)
269 #define NFSD4_SLOT_INITIALIZED	(1 << 2)
270 #define NFSD4_SLOT_CACHED	(1 << 3)
271 #define NFSD4_SLOT_REUSED	(1 << 4)
272 	u8	sl_flags;
273 	char	sl_data[];
274 };
275 
276 struct nfsd4_channel_attrs {
277 	u32		headerpadsz;
278 	u32		maxreq_sz;
279 	u32		maxresp_sz;
280 	u32		maxresp_cached;
281 	u32		maxops;
282 	u32		maxreqs;
283 	u32		nr_rdma_attrs;
284 	u32		rdma_attrs;
285 };
286 
287 struct nfsd4_cb_sec {
288 	u32	flavor; /* (u32)(-1) used to mean "no valid flavor" */
289 	kuid_t	uid;
290 	kgid_t	gid;
291 };
292 
293 struct nfsd4_create_session {
294 	clientid_t			clientid;
295 	struct nfs4_sessionid		sessionid;
296 	u32				seqid;
297 	u32				flags;
298 	struct nfsd4_channel_attrs	fore_channel;
299 	struct nfsd4_channel_attrs	back_channel;
300 	u32				callback_prog;
301 	struct nfsd4_cb_sec		cb_sec;
302 };
303 
304 struct nfsd4_backchannel_ctl {
305 	u32	bc_cb_program;
306 	struct nfsd4_cb_sec		bc_cb_sec;
307 };
308 
309 struct nfsd4_bind_conn_to_session {
310 	struct nfs4_sessionid		sessionid;
311 	u32				dir;
312 };
313 
314 /* The single slot clientid cache structure */
315 struct nfsd4_clid_slot {
316 	u32				sl_seqid;
317 	__be32				sl_status;
318 	struct nfsd4_create_session	sl_cr_ses;
319 };
320 
321 struct nfsd4_conn {
322 	struct list_head cn_persession;
323 	struct svc_xprt *cn_xprt;
324 	struct svc_xpt_user cn_xpt_user;
325 	struct nfsd4_session *cn_session;
326 /* CDFC4_FORE, CDFC4_BACK: */
327 	unsigned char cn_flags;
328 };
329 
330 /* Maximum number of slots that nfsd will use in the backchannel */
331 #define NFSD_BC_SLOT_TABLE_SIZE		(sizeof(u32) * 8)
332 
333 /*
334  * Representation of a v4.1+ session. These are refcounted in a similar fashion
335  * to the nfs4_client. References are only taken when the server is actively
336  * working on the object (primarily during the processing of compounds).
337  */
338 struct nfsd4_session {
339 	atomic_t		se_ref;
340 	spinlock_t		se_lock;
341 	u32			se_cb_slot_avail; /* bitmap of available slots */
342 	u32			se_cb_highest_slot;	/* highest slot client wants */
343 	u32			se_cb_prog;
344 	struct list_head	se_hash;	/* hash by sessionid */
345 	struct list_head	se_perclnt;
346 	struct list_head	se_all_sessions;/* global list of sessions */
347 	struct nfs4_client	*se_client;
348 	struct nfs4_sessionid	se_sessionid;
349 	struct nfsd4_channel_attrs se_fchannel;
350 	struct nfsd4_cb_sec	se_cb_sec;
351 	struct list_head	se_conns;
352 	u32			se_cb_seq_nr[NFSD_BC_SLOT_TABLE_SIZE];
353 	struct xarray		se_slots;	/* forward channel slots */
354 	u16			se_slot_gen;
355 	bool			se_dead;
356 	u32			se_target_maxslots;
357 };
358 
359 /* formatted contents of nfs4_sessionid */
360 struct nfsd4_sessionid {
361 	clientid_t	clientid;
362 	u32		sequence;
363 	u32		reserved;
364 };
365 
366 #define HEXDIR_LEN     33 /* hex version of 16 byte md5 of cl_name plus '\0' */
367 
368 /*
369  *       State                Meaning                  Where set
370  * --------------------------------------------------------------------------
371  * | NFSD4_ACTIVE      | Confirmed, active    | Default                     |
372  * |------------------- ----------------------------------------------------|
373  * | NFSD4_COURTESY    | Courtesy state.      | nfs4_get_client_reaplist    |
374  * |                   | Lease/lock/share     |                             |
375  * |                   | reservation conflict |                             |
376  * |                   | can cause Courtesy   |                             |
377  * |                   | client to be expired |                             |
378  * |------------------------------------------------------------------------|
379  * | NFSD4_EXPIRABLE   | Courtesy client to be| nfs4_laundromat             |
380  * |                   | expired by Laundromat| try_to_expire_client        |
381  * |                   | due to conflict      |                             |
382  * |------------------------------------------------------------------------|
383  */
384 enum {
385 	NFSD4_ACTIVE = 0,
386 	NFSD4_COURTESY,
387 	NFSD4_EXPIRABLE,
388 };
389 
390 /*
391  * struct nfs4_client - one per client.  Clientids live here.
392  *
393  * The initial object created by an NFS client using SETCLIENTID (for NFSv4.0)
394  * or EXCHANGE_ID (for NFSv4.1+). These objects are refcounted and timestamped.
395  * Each nfsd_net_ns object contains a set of these and they are tracked via
396  * short and long form clientid. They are hashed and searched for under the
397  * per-nfsd_net client_lock spinlock.
398  *
399  * References to it are only held during the processing of compounds, and in
400  * certain other operations. In their "resting state" they have a refcount of
401  * 0. If they are not renewed within a lease period, they become eligible for
402  * destruction by the laundromat.
403  *
404  * These objects can also be destroyed if the client sends certain forms of
405  * SETCLIENTID or EXCHANGE_ID operations.
406  *
407  * Care is taken *not* to do this however when the objects have an elevated
408  * refcount.
409  *
410  * o Each nfs4_client is hashed by clientid
411  *
412  * o Each nfs4_clients is also hashed by name (the opaque quantity initially
413  *   sent by the client to identify itself).
414  *
415  * o cl_perclient list is used to ensure no dangling stateowner references
416  *   when we expire the nfs4_client
417  */
418 struct nfs4_client {
419 	struct list_head	cl_idhash; 	/* hash by cl_clientid.id */
420 	struct rb_node		cl_namenode;	/* link into by-name trees */
421 	struct list_head	*cl_ownerstr_hashtbl;
422 	struct list_head	cl_openowners;
423 	struct idr		cl_stateids;	/* stateid lookup */
424 	struct list_head	cl_delegations;
425 	struct list_head	cl_revoked;	/* unacknowledged, revoked 4.1 state */
426 	struct list_head        cl_lru;         /* tail queue */
427 #ifdef CONFIG_NFSD_PNFS
428 	struct list_head	cl_lo_states;	/* outstanding layout states */
429 #endif
430 	struct xdr_netobj	cl_name; 	/* id generated by client */
431 	nfs4_verifier		cl_verifier; 	/* generated by client */
432 	time64_t		cl_time;	/* time of last lease renewal */
433 	struct sockaddr_storage	cl_addr; 	/* client ipaddress */
434 	bool			cl_mach_cred;	/* SP4_MACH_CRED in force */
435 	struct svc_cred		cl_cred; 	/* setclientid principal */
436 	clientid_t		cl_clientid;	/* generated by server */
437 	nfs4_verifier		cl_confirm;	/* generated by server */
438 	u32			cl_minorversion;
439 	atomic_t		cl_admin_revoked; /* count of admin-revoked states */
440 	/* NFSv4.1 client implementation id: */
441 	struct xdr_netobj	cl_nii_domain;
442 	struct xdr_netobj	cl_nii_name;
443 	struct timespec64	cl_nii_time;
444 
445 	/* for v4.0 and v4.1 callbacks: */
446 	struct nfs4_cb_conn	cl_cb_conn;
447 #define NFSD4_CLIENT_CB_UPDATE		(0)
448 #define NFSD4_CLIENT_CB_KILL		(1)
449 #define NFSD4_CLIENT_STABLE		(2)	/* client on stable storage */
450 #define NFSD4_CLIENT_RECLAIM_COMPLETE	(3)	/* reclaim_complete done */
451 #define NFSD4_CLIENT_CONFIRMED		(4)	/* client is confirmed */
452 #define NFSD4_CLIENT_UPCALL_LOCK	(5)	/* upcall serialization */
453 #define NFSD4_CLIENT_CB_FLAG_MASK	(1 << NFSD4_CLIENT_CB_UPDATE | \
454 					 1 << NFSD4_CLIENT_CB_KILL)
455 #define NFSD4_CLIENT_CB_RECALL_ANY	(6)
456 	unsigned long		cl_flags;
457 
458 	struct workqueue_struct *cl_callback_wq;
459 	const struct cred	*cl_cb_cred;
460 	struct rpc_clnt		*cl_cb_client;
461 	u32			cl_cb_ident;
462 #define NFSD4_CB_UP		0
463 #define NFSD4_CB_UNKNOWN	1
464 #define NFSD4_CB_DOWN		2
465 #define NFSD4_CB_FAULT		3
466 	int			cl_cb_state;
467 	struct nfsd4_callback	cl_cb_null;
468 	struct nfsd4_session	*cl_cb_session;
469 
470 	/* for all client information that callback code might need: */
471 	spinlock_t		cl_lock;
472 
473 	/* for nfs41 */
474 	struct list_head	cl_sessions;
475 	struct nfsd4_clid_slot	cl_cs_slot;	/* create_session slot */
476 	u32			cl_exchange_flags;
477 	/* number of rpc's in progress over an associated session: */
478 	atomic_t		cl_rpc_users;
479 	struct nfsdfs_client	cl_nfsdfs;
480 	struct nfs4_op_map      cl_spo_must_allow;
481 
482 	/* debugging info directory under nfsd/clients/ : */
483 	struct dentry		*cl_nfsd_dentry;
484 	/* 'info' file within that directory. Ref is not counted,
485 	 * but will remain valid iff cl_nfsd_dentry != NULL
486 	 */
487 	struct dentry		*cl_nfsd_info_dentry;
488 
489 	struct rpc_wait_queue	cl_cb_waitq;	/* backchannel callers may */
490 						/* wait here for slots */
491 	struct net		*net;
492 	struct list_head	async_copies;	/* list of async copies */
493 	spinlock_t		async_lock;	/* lock for async copies */
494 	atomic_t		cl_cb_inflight;	/* Outstanding callbacks */
495 
496 	unsigned int		cl_state;
497 	atomic_t		cl_delegs_in_recall;
498 
499 	struct nfsd4_cb_recall_any	*cl_ra;
500 	time64_t		cl_ra_time;
501 	struct list_head	cl_ra_cblist;
502 };
503 
504 /* struct nfs4_client_reset
505  * one per old client. Populates reset_str_hashtbl. Filled from conf_id_hashtbl
506  * upon lease reset, or from upcall to state_daemon (to read in state
507  * from non-volitile storage) upon reboot.
508  */
509 struct nfs4_client_reclaim {
510 	struct list_head	cr_strhash;	/* hash by cr_name */
511 	struct nfs4_client	*cr_clp;	/* pointer to associated clp */
512 	struct xdr_netobj	cr_name;	/* recovery dir name */
513 	struct xdr_netobj	cr_princhash;
514 };
515 
516 /* A reasonable value for REPLAY_ISIZE was estimated as follows:
517  * The OPEN response, typically the largest, requires
518  *   4(status) + 8(stateid) + 20(changeinfo) + 4(rflags) +  8(verifier) +
519  *   4(deleg. type) + 8(deleg. stateid) + 4(deleg. recall flag) +
520  *   20(deleg. space limit) + ~32(deleg. ace) = 112 bytes
521  */
522 
523 #define NFSD4_REPLAY_ISIZE       112
524 
525 /*
526  * Replay buffer, where the result of the last seqid-mutating operation
527  * is cached.
528  */
529 struct nfs4_replay {
530 	__be32			rp_status;
531 	unsigned int		rp_buflen;
532 	char			*rp_buf;
533 	struct knfsd_fh		rp_openfh;
534 	int			rp_locked;
535 	char			rp_ibuf[NFSD4_REPLAY_ISIZE];
536 };
537 
538 struct nfs4_stateowner;
539 
540 struct nfs4_stateowner_operations {
541 	void (*so_unhash)(struct nfs4_stateowner *);
542 	void (*so_free)(struct nfs4_stateowner *);
543 };
544 
545 /*
546  * A core object that represents either an open or lock owner. The object and
547  * lock owner objects have one of these embedded within them. Refcounts and
548  * other fields common to both owner types are contained within these
549  * structures.
550  */
551 struct nfs4_stateowner {
552 	struct list_head			so_strhash;
553 	struct list_head			so_stateids;
554 	struct nfs4_client			*so_client;
555 	const struct nfs4_stateowner_operations	*so_ops;
556 	/* after increment in nfsd4_bump_seqid, represents the next
557 	 * sequence id expected from the client: */
558 	atomic_t				so_count;
559 	u32					so_seqid;
560 	struct xdr_netobj			so_owner; /* open owner name */
561 	struct nfs4_replay			so_replay;
562 	bool					so_is_open_owner;
563 };
564 
565 /*
566  * When a file is opened, the client provides an open state owner opaque string
567  * that indicates the "owner" of that open. These objects are refcounted.
568  * References to it are held by each open state associated with it. This object
569  * is a superset of the nfs4_stateowner struct.
570  */
571 struct nfs4_openowner {
572 	struct nfs4_stateowner	oo_owner; /* must be first field */
573 	struct list_head        oo_perclient;
574 	/*
575 	 * We keep around openowners a little while after last close,
576 	 * which saves clients from having to confirm, and allows us to
577 	 * handle close replays if they come soon enough.  The close_lru
578 	 * is a list of such openowners, to be reaped by the laundromat
579 	 * thread eventually if they remain unused:
580 	 */
581 	struct list_head	oo_close_lru;
582 	struct nfs4_ol_stateid *oo_last_closed_stid;
583 	time64_t		oo_time; /* time of placement on so_close_lru */
584 #define NFS4_OO_CONFIRMED   1
585 	unsigned char		oo_flags;
586 };
587 
588 /*
589  * Represents a generic "lockowner". Similar to an openowner. References to it
590  * are held by the lock stateids that are created on its behalf. This object is
591  * a superset of the nfs4_stateowner struct.
592  */
593 struct nfs4_lockowner {
594 	struct nfs4_stateowner	lo_owner;	/* must be first element */
595 	struct list_head	lo_blocked;	/* blocked file_locks */
596 };
597 
598 static inline struct nfs4_openowner * openowner(struct nfs4_stateowner *so)
599 {
600 	return container_of(so, struct nfs4_openowner, oo_owner);
601 }
602 
603 static inline struct nfs4_lockowner * lockowner(struct nfs4_stateowner *so)
604 {
605 	return container_of(so, struct nfs4_lockowner, lo_owner);
606 }
607 
608 /*
609  * Per-client state indicating no. of opens and outstanding delegations
610  * on a file from a particular client.'od' stands for 'open & delegation'
611  */
612 struct nfs4_clnt_odstate {
613 	struct nfs4_client	*co_client;
614 	struct nfs4_file	*co_file;
615 	struct list_head	co_perfile;
616 	refcount_t		co_odcount;
617 };
618 
619 /*
620  * nfs4_file: a file opened by some number of (open) nfs4_stateowners.
621  *
622  * These objects are global. nfsd keeps one instance of a nfs4_file per
623  * filehandle (though it may keep multiple file descriptors for each). Each
624  * inode can have multiple filehandles associated with it, so there is
625  * (potentially) a many to one relationship between this struct and struct
626  * inode.
627  */
628 struct nfs4_file {
629 	refcount_t		fi_ref;
630 	struct inode *		fi_inode;
631 	bool			fi_aliased;
632 	spinlock_t		fi_lock;
633 	struct rhlist_head	fi_rlist;
634 	struct list_head        fi_stateids;
635 	union {
636 		struct list_head	fi_delegations;
637 		struct rcu_head		fi_rcu;
638 	};
639 	struct list_head	fi_clnt_odstate;
640 	/* One each for O_RDONLY, O_WRONLY, O_RDWR: */
641 	struct nfsd_file	*fi_fds[3];
642 	/*
643 	 * Each open or lock stateid contributes 0-4 to the counts
644 	 * below depending on which bits are set in st_access_bitmap:
645 	 *     1 to fi_access[O_RDONLY] if NFS4_SHARE_ACCES_READ is set
646 	 *   + 1 to fi_access[O_WRONLY] if NFS4_SHARE_ACCESS_WRITE is set
647 	 *   + 1 to both of the above if NFS4_SHARE_ACCESS_BOTH is set.
648 	 */
649 	atomic_t		fi_access[2];
650 	u32			fi_share_deny;
651 	struct nfsd_file	*fi_deleg_file;
652 	int			fi_delegees;
653 	struct knfsd_fh		fi_fhandle;
654 	bool			fi_had_conflict;
655 #ifdef CONFIG_NFSD_PNFS
656 	struct list_head	fi_lo_states;
657 	atomic_t		fi_lo_recalls;
658 #endif
659 };
660 
661 /*
662  * A generic struct representing either a open or lock stateid. The nfs4_client
663  * holds a reference to each of these objects, and they in turn hold a
664  * reference to their respective stateowners. The client's reference is
665  * released in response to a close or unlock (depending on whether it's an open
666  * or lock stateid) or when the client is being destroyed.
667  *
668  * In the case of v4.0 open stateids, these objects are preserved for a little
669  * while after close in order to handle CLOSE replays. Those are eventually
670  * reclaimed via a LRU scheme by the laundromat.
671  *
672  * This object is a superset of the nfs4_stid. "ol" stands for "Open or Lock".
673  * Better suggestions welcome.
674  */
675 struct nfs4_ol_stateid {
676 	struct nfs4_stid		st_stid;
677 	struct list_head		st_perfile;
678 	struct list_head		st_perstateowner;
679 	struct list_head		st_locks;
680 	struct nfs4_stateowner		*st_stateowner;
681 	struct nfs4_clnt_odstate	*st_clnt_odstate;
682 /*
683  * These bitmasks use 3 separate bits for READ, ALLOW, and BOTH; see the
684  * comment above bmap_to_share_mode() for explanation:
685  */
686 	unsigned char			st_access_bmap;
687 	unsigned char			st_deny_bmap;
688 	struct nfs4_ol_stateid		*st_openstp;
689 	struct mutex			st_mutex;
690 };
691 
692 static inline struct nfs4_ol_stateid *openlockstateid(struct nfs4_stid *s)
693 {
694 	return container_of(s, struct nfs4_ol_stateid, st_stid);
695 }
696 
697 struct nfs4_layout_stateid {
698 	struct nfs4_stid		ls_stid;
699 	struct list_head		ls_perclnt;
700 	struct list_head		ls_perfile;
701 	spinlock_t			ls_lock;
702 	struct list_head		ls_layouts;
703 	u32				ls_layout_type;
704 	struct nfsd_file		*ls_file;
705 	struct nfsd4_callback		ls_recall;
706 	stateid_t			ls_recall_sid;
707 	bool				ls_recalled;
708 	struct mutex			ls_mutex;
709 };
710 
711 static inline struct nfs4_layout_stateid *layoutstateid(struct nfs4_stid *s)
712 {
713 	return container_of(s, struct nfs4_layout_stateid, ls_stid);
714 }
715 
716 /* flags for preprocess_seqid_op() */
717 #define RD_STATE	        0x00000010
718 #define WR_STATE	        0x00000020
719 
720 enum nfsd4_cb_op {
721 	NFSPROC4_CLNT_CB_NULL = 0,
722 	NFSPROC4_CLNT_CB_RECALL,
723 	NFSPROC4_CLNT_CB_LAYOUT,
724 	NFSPROC4_CLNT_CB_OFFLOAD,
725 	NFSPROC4_CLNT_CB_SEQUENCE,
726 	NFSPROC4_CLNT_CB_NOTIFY_LOCK,
727 	NFSPROC4_CLNT_CB_RECALL_ANY,
728 	NFSPROC4_CLNT_CB_GETATTR,
729 };
730 
731 /* Returns true iff a is later than b: */
732 static inline bool nfsd4_stateid_generation_after(stateid_t *a, stateid_t *b)
733 {
734 	return (s32)(a->si_generation - b->si_generation) > 0;
735 }
736 
737 /*
738  * When a client tries to get a lock on a file, we set one of these objects
739  * on the blocking lock. When the lock becomes free, we can then issue a
740  * CB_NOTIFY_LOCK to the server.
741  */
742 struct nfsd4_blocked_lock {
743 	struct list_head	nbl_list;
744 	struct list_head	nbl_lru;
745 	time64_t		nbl_time;
746 	struct file_lock	nbl_lock;
747 	struct knfsd_fh		nbl_fh;
748 	struct nfsd4_callback	nbl_cb;
749 	struct kref		nbl_kref;
750 };
751 
752 struct nfsd4_compound_state;
753 struct nfsd_net;
754 struct nfsd4_copy;
755 
756 extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
757 		struct nfsd4_compound_state *cstate, struct svc_fh *fhp,
758 		stateid_t *stateid, int flags, struct nfsd_file **filp,
759 		struct nfs4_stid **cstid);
760 __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
761 			    stateid_t *stateid, unsigned short typemask,
762 			    unsigned short statusmask,
763 			    struct nfs4_stid **s, struct nfsd_net *nn);
764 struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
765 				  void (*sc_free)(struct nfs4_stid *));
766 int nfs4_init_copy_state(struct nfsd_net *nn, struct nfsd4_copy *copy);
767 void nfs4_free_copy_state(struct nfsd4_copy *copy);
768 struct nfs4_cpntf_state *nfs4_alloc_init_cpntf_state(struct nfsd_net *nn,
769 			struct nfs4_stid *p_stid);
770 void nfs4_put_stid(struct nfs4_stid *s);
771 void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
772 void nfs4_remove_reclaim_record(struct nfs4_client_reclaim *, struct nfsd_net *);
773 extern void nfs4_release_reclaim(struct nfsd_net *);
774 extern struct nfs4_client_reclaim *nfsd4_find_reclaim_client(struct xdr_netobj name,
775 							struct nfsd_net *nn);
776 extern __be32 nfs4_check_open_reclaim(struct nfs4_client *);
777 extern void nfsd4_probe_callback(struct nfs4_client *clp);
778 extern void nfsd4_probe_callback_sync(struct nfs4_client *clp);
779 extern void nfsd4_change_callback(struct nfs4_client *clp, struct nfs4_cb_conn *);
780 extern void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
781 		const struct nfsd4_callback_ops *ops, enum nfsd4_cb_op op);
782 extern bool nfsd4_run_cb(struct nfsd4_callback *cb);
783 extern void nfsd4_shutdown_callback(struct nfs4_client *);
784 extern void nfsd4_shutdown_copy(struct nfs4_client *clp);
785 void nfsd4_async_copy_reaper(struct nfsd_net *nn);
786 bool nfsd4_has_active_async_copies(struct nfs4_client *clp);
787 extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(struct xdr_netobj name,
788 				struct xdr_netobj princhash, struct nfsd_net *nn);
789 extern bool nfs4_has_reclaimed_state(struct xdr_netobj name, struct nfsd_net *nn);
790 
791 void put_nfs4_file(struct nfs4_file *fi);
792 extern void nfs4_put_cpntf_state(struct nfsd_net *nn,
793 				 struct nfs4_cpntf_state *cps);
794 extern __be32 manage_cpntf_state(struct nfsd_net *nn, stateid_t *st,
795 				 struct nfs4_client *clp,
796 				 struct nfs4_cpntf_state **cps);
797 static inline void get_nfs4_file(struct nfs4_file *fi)
798 {
799 	refcount_inc(&fi->fi_ref);
800 }
801 struct nfsd_file *find_any_file(struct nfs4_file *f);
802 
803 #ifdef CONFIG_NFSD_V4
804 void nfsd4_revoke_states(struct net *net, struct super_block *sb);
805 #else
806 static inline void nfsd4_revoke_states(struct net *net, struct super_block *sb)
807 {
808 }
809 #endif
810 
811 /* grace period management */
812 void nfsd4_end_grace(struct nfsd_net *nn);
813 
814 /* nfs4recover operations */
815 extern int nfsd4_client_tracking_init(struct net *net);
816 extern void nfsd4_client_tracking_exit(struct net *net);
817 extern void nfsd4_client_record_create(struct nfs4_client *clp);
818 extern void nfsd4_client_record_remove(struct nfs4_client *clp);
819 extern int nfsd4_client_record_check(struct nfs4_client *clp);
820 extern void nfsd4_record_grace_done(struct nfsd_net *nn);
821 
822 static inline bool try_to_expire_client(struct nfs4_client *clp)
823 {
824 	cmpxchg(&clp->cl_state, NFSD4_COURTESY, NFSD4_EXPIRABLE);
825 	return clp->cl_state == NFSD4_EXPIRABLE;
826 }
827 
828 extern __be32 nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp,
829 		struct dentry *dentry, struct nfs4_delegation **pdp);
830 #endif   /* NFSD4_STATE_H */
831