summaryrefslogtreecommitdiff
path: root/fs/afs/internal.h
blob: 1fadf40551fd3e8ca2ee03a3bec61425bc2965f2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
/* internal AFS stuff
 *
 * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/ktime.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/rxrpc.h>
#include <linux/key.h>
#include <linux/workqueue.h>
#include <linux/sched.h>
#include <linux/fscache.h>
#include <linux/backing-dev.h>
#include <linux/uuid.h>
#include <net/net_namespace.h>
#include <net/af_rxrpc.h>

#include "afs.h"
#include "afs_vl.h"

#define AFS_CELL_MAX_ADDRS 15

struct pagevec;
struct afs_call;

struct afs_mount_params {
	bool			rwpath;		/* T if the parent should be considered R/W */
	bool			force;		/* T to force cell type */
	bool			autocell;	/* T if set auto mount operation */
	afs_voltype_t		type;		/* type of volume requested */
	int			volnamesz;	/* size of volume name */
	const char		*volname;	/* name of volume to mount */
	struct afs_net		*net;		/* Network namespace in effect */
	struct afs_cell		*cell;		/* cell in which to find volume */
	struct afs_volume	*volume;	/* volume record */
	struct key		*key;		/* key to use for secure mounting */
};

struct afs_iget_data {
	struct afs_fid		fid;
	struct afs_volume	*volume;	/* volume on which resides */
};

enum afs_call_state {
	AFS_CALL_REQUESTING,	/* request is being sent for outgoing call */
	AFS_CALL_AWAIT_REPLY,	/* awaiting reply to outgoing call */
	AFS_CALL_AWAIT_OP_ID,	/* awaiting op ID on incoming call */
	AFS_CALL_AWAIT_REQUEST,	/* awaiting request data on incoming call */
	AFS_CALL_REPLYING,	/* replying to incoming call */
	AFS_CALL_AWAIT_ACK,	/* awaiting final ACK of incoming call */
	AFS_CALL_COMPLETE,	/* Completed or failed */
};

/*
 * List of server addresses.
 */
struct afs_addr_list {
	struct rcu_head		rcu;		/* Must be first */
	refcount_t		usage;
	u32			version;	/* Version */
	unsigned short		nr_addrs;
	unsigned short		index;		/* Address currently in use */
	unsigned short		nr_ipv4;	/* Number of IPv4 addresses */
	struct sockaddr_rxrpc	addrs[];
};

/*
 * a record of an in-progress RxRPC call
 */
struct afs_call {
	const struct afs_call_type *type;	/* type of call */
	wait_queue_head_t	waitq;		/* processes awaiting completion */
	struct work_struct	async_work;	/* async I/O processor */
	struct work_struct	work;		/* actual work processor */
	struct rxrpc_call	*rxcall;	/* RxRPC call handle */
	struct key		*key;		/* security for this call */
	struct afs_net		*net;		/* The network namespace */
	struct afs_server	*cm_server;	/* Server affected by incoming CM call */
	struct afs_cb_interest	*cbi;		/* Callback interest for server used */
	void			*request;	/* request data (first part) */
	struct address_space	*mapping;	/* page set */
	struct afs_writeback	*wb;		/* writeback being performed */
	void			*buffer;	/* reply receive buffer */
	void			*reply[4];	/* Where to put the reply */
	pgoff_t			first;		/* first page in mapping to deal with */
	pgoff_t			last;		/* last page in mapping to deal with */
	size_t			offset;		/* offset into received data store */
	atomic_t		usage;
	enum afs_call_state	state;
	int			error;		/* error code */
	u32			abort_code;	/* Remote abort ID or 0 */
	unsigned		request_size;	/* size of request data */
	unsigned		reply_max;	/* maximum size of reply */
	unsigned		first_offset;	/* offset into mapping[first] */
	unsigned int		cb_break;	/* cb_break + cb_s_break before the call */
	union {
		unsigned	last_to;	/* amount of mapping[last] */
		unsigned	count2;		/* count used in unmarshalling */
	};
	unsigned char		unmarshall;	/* unmarshalling phase */
	bool			incoming;	/* T if incoming call */
	bool			send_pages;	/* T if data from mapping should be sent */
	bool			need_attention;	/* T if RxRPC poked us */
	bool			async;		/* T if asynchronous */
	bool			ret_reply0;	/* T if should return reply[0] on success */
	bool			upgrade;	/* T to request service upgrade */
	u16			service_id;	/* RxRPC service ID to call */
	u32			operation_ID;	/* operation ID for an incoming call */
	u32			count;		/* count for use in unmarshalling */
	__be32			tmp;		/* place to extract temporary data */
	afs_dataversion_t	store_version;	/* updated version expected from store */
};

struct afs_call_type {
	const char *name;

	/* deliver request or reply data to an call
	 * - returning an error will cause the call to be aborted
	 */
	int (*deliver)(struct afs_call *call);

	/* clean up a call */
	void (*destructor)(struct afs_call *call);

	/* Work function */
	void (*work)(struct work_struct *work);
};

/*
 * Record of an outstanding read operation on a vnode.
 */
struct afs_read {
	loff_t			pos;		/* Where to start reading */
	loff_t			len;		/* How much we're asking for */
	loff_t			actual_len;	/* How much we're actually getting */
	loff_t			remain;		/* Amount remaining */
	atomic_t		usage;
	unsigned int		index;		/* Which page we're reading into */
	unsigned int		nr_pages;
	void (*page_done)(struct afs_call *, struct afs_read *);
	struct page		*pages[];
};

/*
 * record of an outstanding writeback on a vnode
 */
struct afs_writeback {
	struct list_head	link;		/* link in vnode->writebacks */
	struct work_struct	writer;		/* work item to perform the writeback */
	struct afs_vnode	*vnode;		/* vnode to which this write applies */
	struct key		*key;		/* owner of this write */
	wait_queue_head_t	waitq;		/* completion and ready wait queue */
	pgoff_t			first;		/* first page in batch */
	pgoff_t			point;		/* last page in current store op */
	pgoff_t			last;		/* last page in batch (inclusive) */
	unsigned		offset_first;	/* offset into first page of start of write */
	unsigned		to_last;	/* offset into last page of end of write */
	int			num_conflicts;	/* count of conflicting writes in list */
	int			usage;
	bool			conflicts;	/* T if has dependent conflicts */
	enum {
		AFS_WBACK_SYNCING,		/* synchronisation being performed */
		AFS_WBACK_PENDING,		/* write pending */
		AFS_WBACK_CONFLICTING,		/* conflicting writes posted */
		AFS_WBACK_WRITING,		/* writing back */
		AFS_WBACK_COMPLETE		/* the writeback record has been unlinked */
	} state __attribute__((packed));
};

/*
 * AFS superblock private data
 * - there's one superblock per volume
 */
struct afs_super_info {
	struct afs_net		*net;		/* Network namespace */
	struct afs_cell		*cell;		/* The cell in which the volume resides */
	struct afs_volume	*volume;	/* volume record */
};

static inline struct afs_super_info *AFS_FS_S(struct super_block *sb)
{
	return sb->s_fs_info;
}

extern struct file_system_type afs_fs_type;

/*
 * AFS network namespace record.
 */
struct afs_net {
	struct afs_uuid		uuid;
	bool			live;		/* F if this namespace is being removed */

	/* AF_RXRPC I/O stuff */
	struct socket		*socket;
	struct afs_call		*spare_incoming_call;
	struct work_struct	charge_preallocation_work;
	struct mutex		socket_mutex;
	atomic_t		nr_outstanding_calls;
	atomic_t		nr_superblocks;

	/* Cell database */
	struct rb_root		cells;
	struct afs_cell		*ws_cell;
	struct work_struct	cells_manager;
	struct timer_list	cells_timer;
	atomic_t		cells_outstanding;
	seqlock_t		cells_lock;

	spinlock_t		proc_cells_lock;
	struct list_head	proc_cells;

	/* Known servers.  Theoretically each fileserver can only be in one
	 * cell, but in practice, people create aliases and subsets and there's
	 * no easy way to distinguish them.
	 */
	seqlock_t		fs_lock;	/* For fs_servers */
	struct rb_root		fs_servers;	/* afs_server (by server UUID or address) */
	struct list_head	fs_updates;	/* afs_server (by update_at) */
	struct hlist_head	fs_proc;	/* procfs servers list */

	struct hlist_head	fs_addresses4;	/* afs_server (by lowest IPv4 addr) */
	struct hlist_head	fs_addresses6;	/* afs_server (by lowest IPv6 addr) */
	seqlock_t		fs_addr_lock;	/* For fs_addresses[46] */

	struct work_struct	fs_manager;
	struct timer_list	fs_timer;
	atomic_t		servers_outstanding;

	/* File locking renewal management */
	struct mutex		lock_manager_mutex;

	/* Misc */
	struct proc_dir_entry	*proc_afs;		/* /proc/net/afs directory */
};

extern struct afs_net __afs_net;// Dummy AFS network namespace; TODO: replace with real netns

enum afs_cell_state {
	AFS_CELL_UNSET,
	AFS_CELL_ACTIVATING,
	AFS_CELL_ACTIVE,
	AFS_CELL_DEACTIVATING,
	AFS_CELL_INACTIVE,
	AFS_CELL_FAILED,
};

/*
 * AFS cell record.
 *
 * This is a tricky concept to get right as it is possible to create aliases
 * simply by pointing AFSDB/SRV records for two names at the same set of VL
 * servers; it is also possible to do things like setting up two sets of VL
 * servers, one of which provides a superset of the volumes provided by the
 * other (for internal/external division, for example).
 *
 * Cells only exist in the sense that (a) a cell's name maps to a set of VL
 * servers and (b) a cell's name is used by the client to select the key to use
 * for authentication and encryption.  The cell name is not typically used in
 * the protocol.
 *
 * There is no easy way to determine if two cells are aliases or one is a
 * subset of another.
 */
struct afs_cell {
	union {
		struct rcu_head	rcu;
		struct rb_node	net_node;	/* Node in net->cells */
	};
	struct afs_net		*net;
	struct key		*anonymous_key;	/* anonymous user key for this cell */
	struct work_struct	manager;	/* Manager for init/deinit/dns */
	struct list_head	proc_link;	/* /proc cell list link */
#ifdef CONFIG_AFS_FSCACHE
	struct fscache_cookie	*cache;		/* caching cookie */
#endif
	time64_t		dns_expiry;	/* Time AFSDB/SRV record expires */
	time64_t		last_inactive;	/* Time of last drop of usage count */
	atomic_t		usage;
	unsigned long		flags;
#define AFS_CELL_FL_NOT_READY	0		/* The cell record is not ready for use */
#define AFS_CELL_FL_NO_GC	1		/* The cell was added manually, don't auto-gc */
#define AFS_CELL_FL_NOT_FOUND	2		/* Permanent DNS error */
#define AFS_CELL_FL_DNS_FAIL	3		/* Failed to access DNS */
#define AFS_CELL_FL_NO_LOOKUP_YET 4		/* Not completed first DNS lookup yet */
	enum afs_cell_state	state;
	short			error;

	/* Active fileserver interaction state. */
	struct list_head	proc_volumes;	/* procfs volume list */
	rwlock_t		proc_lock;

	/* VL server list. */
	rwlock_t		vl_addrs_lock;	/* Lock on vl_addrs */
	struct afs_addr_list	__rcu *vl_addrs; /* List of VL servers */
	u8			name_len;	/* Length of name */
	char			name[64 + 1];	/* Cell name, case-flattened and NUL-padded */
};

/*
 * Cached VLDB entry.
 *
 * This is pointed to by cell->vldb_entries, indexed by name.
 */
struct afs_vldb_entry {
	afs_volid_t		vid[3];		/* Volume IDs for R/W, R/O and Bak volumes */

	unsigned long		flags;
#define AFS_VLDB_HAS_RW		0		/* - R/W volume exists */
#define AFS_VLDB_HAS_RO		1		/* - R/O volume exists */
#define AFS_VLDB_HAS_BAK	2		/* - Backup volume exists */
#define AFS_VLDB_QUERY_VALID	3		/* - Record is valid */
#define AFS_VLDB_QUERY_ERROR	4		/* - VL server returned error */

	uuid_t			fs_server[AFS_NMAXNSERVERS];
	u8			fs_mask[AFS_NMAXNSERVERS];
#define AFS_VOL_VTM_RW	0x01 /* R/W version of the volume is available (on this server) */
#define AFS_VOL_VTM_RO	0x02 /* R/O version of the volume is available (on this server) */
#define AFS_VOL_VTM_BAK	0x04 /* backup version of the volume is available (on this server) */
	short			error;
	u8			nr_servers;	/* Number of server records */
	u8			name_len;
	u8			name[AFS_MAXVOLNAME + 1]; /* NUL-padded volume name */
};

/*
 * Record of fileserver with which we're actively communicating.
 */
struct afs_server {
	struct rcu_head		rcu;
	union {
		uuid_t		uuid;		/* Server ID */
		struct afs_uuid	_uuid;
	};

	struct afs_addr_list	__rcu *addresses;
	struct rb_node		uuid_rb;	/* Link in net->servers */
	struct hlist_node	addr4_link;	/* Link in net->fs_addresses4 */
	struct hlist_node	addr6_link;	/* Link in net->fs_addresses6 */
	struct hlist_node	proc_link;	/* Link in net->fs_proc */
	struct afs_server	*gc_next;	/* Next server in manager's list */
	time64_t		put_time;	/* Time at which last put */
	time64_t		update_at;	/* Time at which to next update the record */
	unsigned long		flags;
#define AFS_SERVER_FL_NEW	0		/* New server, don't inc cb_s_break */
#define AFS_SERVER_FL_NOT_READY	1		/* The record is not ready for use */
#define AFS_SERVER_FL_NOT_FOUND	2		/* VL server says no such server */
#define AFS_SERVER_FL_VL_FAIL	3		/* Failed to access VL server */
#define AFS_SERVER_FL_UPDATING	4
#define AFS_SERVER_FL_PROBED	5		/* The fileserver has been probed */
#define AFS_SERVER_FL_PROBING	6		/* Fileserver is being probed */
	atomic_t		usage;
	u32			addr_version;	/* Address list version */

	/* file service access */
	rwlock_t		fs_lock;	/* access lock */

	/* callback promise management */
	struct list_head	cb_interests;	/* List of superblocks using this server */
	unsigned		cb_s_break;	/* Break-everything counter. */
	rwlock_t		cb_break_lock;	/* Volume finding lock */
};

/*
 * Interest by a superblock on a server.
 */
struct afs_cb_interest {
	struct list_head	cb_link;	/* Link in server->cb_interests */
	struct afs_server	*server;	/* Server on which this interest resides */
	struct super_block	*sb;		/* Superblock on which inodes reside */
	afs_volid_t		vid;		/* Volume ID to match */
	refcount_t		usage;
};

/*
 * Replaceable server list.
 */
struct afs_server_entry {
	struct afs_server	*server;
	struct afs_cb_interest	*cb_interest;
};

struct afs_server_list {
	refcount_t		usage;
	unsigned short		nr_servers;
	unsigned short		index;		/* Server currently in use */
	unsigned short		vnovol_mask;	/* Servers to be skipped due to VNOVOL */
	unsigned int		seq;		/* Set to ->servers_seq when installed */
	struct afs_server_entry	servers[];
};

/*
 * Live AFS volume management.
 */
struct afs_volume {
	afs_volid_t		vid;		/* volume ID */
	atomic_t		usage;
	time64_t		update_at;	/* Time at which to next update */
	struct afs_cell		*cell;		/* Cell to which belongs (pins ref) */
	struct list_head	proc_link;	/* Link in cell->vl_proc */
	unsigned long		flags;
#define AFS_VOLUME_NEEDS_UPDATE	0	/* - T if an update needs performing */
#define AFS_VOLUME_UPDATING	1	/* - T if an update is in progress */
#define AFS_VOLUME_WAIT		2	/* - T if users must wait for update */
#define AFS_VOLUME_DELETED	3	/* - T if volume appears deleted */
#define AFS_VOLUME_OFFLINE	4	/* - T if volume offline notice given */
#define AFS_VOLUME_BUSY		5	/* - T if volume busy notice given */
#ifdef CONFIG_AFS_FSCACHE
	struct fscache_cookie	*cache;		/* caching cookie */
#endif
	struct afs_server_list	*servers;	/* List of servers on which volume resides */
	rwlock_t		servers_lock;	/* Lock for ->servers */
	unsigned int		servers_seq;	/* Incremented each time ->servers changes */

	afs_voltype_t		type;		/* type of volume */
	short			error;
	char			type_force;	/* force volume type (suppress R/O -> R/W) */
	u8			name_len;
	u8			name[AFS_MAXVOLNAME + 1]; /* NUL-padded volume name */
};

/*
 * AFS inode private data
 */
struct afs_vnode {
	struct inode		vfs_inode;	/* the VFS's inode record */

	struct afs_volume	*volume;	/* volume on which vnode resides */
	struct afs_fid		fid;		/* the file identifier for this inode */
	struct afs_file_status	status;		/* AFS status info for this file */
#ifdef CONFIG_AFS_FSCACHE
	struct fscache_cookie	*cache;		/* caching cookie */
#endif
	struct afs_permits	*permit_cache;	/* cache of permits so far obtained */
	struct mutex		io_lock;	/* Lock for serialising I/O on this mutex */
	struct mutex		validate_lock;	/* lock for validating this vnode */
	spinlock_t		writeback_lock;	/* lock for writebacks */
	spinlock_t		lock;		/* waitqueue/flags lock */
	unsigned long		flags;
#define AFS_VNODE_CB_PROMISED	0		/* Set if vnode has a callback promise */
#define AFS_VNODE_UNSET		1		/* set if vnode attributes not yet set */
#define AFS_VNODE_DIR_MODIFIED	2		/* set if dir vnode's data modified */
#define AFS_VNODE_ZAP_DATA	3		/* set if vnode's data should be invalidated */
#define AFS_VNODE_DELETED	4		/* set if vnode deleted on server */
#define AFS_VNODE_MOUNTPOINT	5		/* set if vnode is a mountpoint symlink */
#define AFS_VNODE_LOCKING	6		/* set if waiting for lock on vnode */
#define AFS_VNODE_READLOCKED	7		/* set if vnode is read-locked on the server */
#define AFS_VNODE_WRITELOCKED	8		/* set if vnode is write-locked on the server */
#define AFS_VNODE_UNLOCKING	9		/* set if vnode is being unlocked on the server */
#define AFS_VNODE_AUTOCELL	10		/* set if Vnode is an auto mount point */
#define AFS_VNODE_PSEUDODIR	11		/* set if Vnode is a pseudo directory */

	struct list_head	writebacks;	/* alterations in pagecache that need writing */
	struct list_head	pending_locks;	/* locks waiting to be granted */
	struct list_head	granted_locks;	/* locks granted on this file */
	struct delayed_work	lock_work;	/* work to be done in locking */
	struct key		*unlock_key;	/* key to be used in unlocking */

	/* outstanding callback notification on this file */
	struct afs_cb_interest	*cb_interest;	/* Server on which this resides */
	unsigned int		cb_s_break;	/* Mass break counter on ->server */
	unsigned int		cb_break;	/* Break counter on vnode */
	seqlock_t		cb_lock;	/* Lock for ->cb_interest, ->status, ->cb_*break */

	time64_t		cb_expires_at;	/* time at which callback expires */
	unsigned		cb_version;	/* callback version */
	afs_callback_type_t	cb_type;	/* type of callback */
};

/*
 * cached security record for one user's attempt to access a vnode
 */
struct afs_permit {
	struct key		*key;		/* RxRPC ticket holding a security context */
	afs_access_t		access;		/* CallerAccess value for this key */
};

/*
 * Immutable cache of CallerAccess records from attempts to access vnodes.
 * These may be shared between multiple vnodes.
 */
struct afs_permits {
	struct rcu_head		rcu;
	struct hlist_node	hash_node;	/* Link in hash */
	unsigned long		h;		/* Hash value for this permit list */
	refcount_t		usage;
	unsigned short		nr_permits;	/* Number of records */
	bool			invalidated;	/* Invalidated due to key change */
	struct afs_permit	permits[];	/* List of permits sorted by key pointer */
};

/*
 * record of one of a system's set of network interfaces
 */
struct afs_interface {
	struct in_addr	address;	/* IPv4 address bound to interface */
	struct in_addr	netmask;	/* netmask applied to address */
	unsigned	mtu;		/* MTU of interface */
};

/*
 * Cursor for iterating over a server's address list.
 */
struct afs_addr_cursor {
	struct afs_addr_list	*alist;		/* Current address list (pins ref) */
	struct sockaddr_rxrpc	*addr;
	u32			abort_code;
	unsigned short		start;		/* Starting point in alist->addrs[] */
	unsigned short		index;		/* Wrapping offset from start to current addr */
	short			error;
	bool			begun;		/* T if we've begun iteration */
	bool			responded;	/* T if the current address responded */
};

/*
 * Cursor for iterating over a set of fileservers.
 */
struct afs_fs_cursor {
	struct afs_addr_cursor	ac;
	struct afs_vnode	*vnode;
	struct afs_server_list	*server_list;	/* Current server list (pins ref) */
	struct afs_cb_interest	*cbi;		/* Server on which this resides (pins ref) */
	struct key		*key;		/* Key for the server */
	unsigned int		cb_break;	/* cb_break + cb_s_break before the call */
	unsigned int		cb_break_2;	/* cb_break + cb_s_break (2nd vnode) */
	unsigned char		start;		/* Initial index in server list */
	unsigned char		index;		/* Number of servers tried beyond start */
	unsigned short		flags;
#define AFS_FS_CURSOR_STOP	0x0001		/* Set to cease iteration */
#define AFS_FS_CURSOR_VBUSY	0x0002		/* Set if seen VBUSY */
#define AFS_FS_CURSOR_VMOVED	0x0004		/* Set if seen VMOVED */
#define AFS_FS_CURSOR_VNOVOL	0x0008		/* Set if seen VNOVOL */
#define AFS_FS_CURSOR_CUR_ONLY	0x0010		/* Set if current server only (file lock held) */
#define AFS_FS_CURSOR_NO_VSLEEP	0x0020		/* Set to prevent sleep on VBUSY, VOFFLINE, ... */
};

/*****************************************************************************/
/*
 * addr_list.c
 */
static inline struct afs_addr_list *afs_get_addrlist(struct afs_addr_list *alist)
{
	if (alist)
		refcount_inc(&alist->usage);
	return alist;
}
extern struct afs_addr_list *afs_alloc_addrlist(unsigned int,
						unsigned short,
						unsigned short);
extern void afs_put_addrlist(struct afs_addr_list *);
extern struct afs_addr_list *afs_parse_text_addrs(const char *, size_t, char,
						  unsigned short, unsigned short);
extern struct afs_addr_list *afs_dns_query(struct afs_cell *, time64_t *);
extern bool afs_iterate_addresses(struct afs_addr_cursor *);
extern int afs_end_cursor(struct afs_addr_cursor *);
extern int afs_set_vl_cursor(struct afs_addr_cursor *, struct afs_cell *);

extern void afs_merge_fs_addr4(struct afs_addr_list *, __be32);

/*
 * cache.c
 */
#ifdef CONFIG_AFS_FSCACHE
extern struct fscache_netfs afs_cache_netfs;
extern struct fscache_cookie_def afs_cell_cache_index_def;
extern struct fscache_cookie_def afs_volume_cache_index_def;
extern struct fscache_cookie_def afs_vnode_cache_index_def;
#else
#define afs_cell_cache_index_def	(*(struct fscache_cookie_def *) NULL)
#define afs_volume_cache_index_def	(*(struct fscache_cookie_def *) NULL)
#define afs_vnode_cache_index_def	(*(struct fscache_cookie_def *) NULL)
#endif

/*
 * callback.c
 */
extern void afs_init_callback_state(struct afs_server *);
extern void afs_break_callback(struct afs_vnode *);
extern void afs_break_callbacks(struct afs_server *, size_t,struct afs_callback[]);

extern int afs_register_server_cb_interest(struct afs_vnode *, struct afs_server_entry *);
extern void afs_put_cb_interest(struct afs_net *, struct afs_cb_interest *);
extern void afs_clear_callback_interests(struct afs_net *, struct afs_server_list *);

static inline struct afs_cb_interest *afs_get_cb_interest(struct afs_cb_interest *cbi)
{
	refcount_inc(&cbi->usage);
	return cbi;
}

/*
 * cell.c
 */
extern int afs_cell_init(struct afs_net *, const char *);
extern struct afs_cell *afs_lookup_cell_rcu(struct afs_net *, const char *, unsigned);
extern struct afs_cell *afs_lookup_cell(struct afs_net *, const char *, unsigned,
					const char *, bool);
extern struct afs_cell *afs_get_cell(struct afs_cell *);
extern void afs_put_cell(struct afs_net *, struct afs_cell *);
extern void afs_manage_cells(struct work_struct *);
extern void afs_cells_timer(struct timer_list *);
extern void __net_exit afs_cell_purge(struct afs_net *);

/*
 * cmservice.c
 */
extern bool afs_cm_incoming_call(struct afs_call *);

/*
 * dir.c
 */
extern const struct inode_operations afs_dir_inode_operations;
extern const struct dentry_operations afs_fs_dentry_operations;
extern const struct file_operations afs_dir_file_operations;

/*
 * file.c
 */
extern const struct address_space_operations afs_fs_aops;
extern const struct inode_operations afs_file_inode_operations;
extern const struct file_operations afs_file_operations;

extern int afs_open(struct inode *, struct file *);
extern int afs_release(struct inode *, struct file *);
extern int afs_fetch_data(struct afs_vnode *, struct key *, struct afs_read *);
extern int afs_page_filler(void *, struct page *);
extern void afs_put_read(struct afs_read *);

/*
 * flock.c
 */
extern struct workqueue_struct *afs_lock_manager;

extern void afs_lock_work(struct work_struct *);
extern void afs_lock_may_be_available(struct afs_vnode *);
extern int afs_lock(struct file *, int, struct file_lock *);
extern int afs_flock(struct file *, int, struct file_lock *);

/*
 * fsclient.c
 */
extern int afs_fs_fetch_file_status(struct afs_fs_cursor *, struct afs_volsync *);
extern int afs_fs_give_up_callbacks(struct afs_net *, struct afs_server *);
extern int afs_fs_fetch_data(struct afs_fs_cursor *, struct afs_read *);
extern int afs_fs_create(struct afs_fs_cursor *, const char *, umode_t,
			 struct afs_fid *, struct afs_file_status *, struct afs_callback *);
extern int afs_fs_remove(struct afs_fs_cursor *, const char *, bool);
extern int afs_fs_link(struct afs_fs_cursor *, struct afs_vnode *, const char *);
extern int afs_fs_symlink(struct afs_fs_cursor *, const char *, const char *,
			  struct afs_fid *, struct afs_file_status *);
extern int afs_fs_rename(struct afs_fs_cursor *, const char *,
			 struct afs_vnode *, const char *);
extern int afs_fs_store_data(struct afs_fs_cursor *, struct afs_writeback *,
			     pgoff_t, pgoff_t, unsigned, unsigned);
extern int afs_fs_setattr(struct afs_fs_cursor *, struct iattr *);
extern int afs_fs_get_volume_status(struct afs_fs_cursor *, struct afs_volume_status *);
extern int afs_fs_set_lock(struct afs_fs_cursor *, afs_lock_type_t);
extern int afs_fs_extend_lock(struct afs_fs_cursor *);
extern int afs_fs_release_lock(struct afs_fs_cursor *);
extern int afs_fs_give_up_all_callbacks(struct afs_net *, struct afs_server *,
					struct afs_addr_cursor *, struct key *);
extern int afs_fs_get_capabilities(struct afs_net *, struct afs_server *,
				   struct afs_addr_cursor *, struct key *);

/*
 * inode.c
 */
extern int afs_fetch_status(struct afs_vnode *, struct key *);
extern int afs_iget5_test(struct inode *, void *);
extern struct inode *afs_iget_autocell(struct inode *, const char *, int,
				       struct key *);
extern struct inode *afs_iget(struct super_block *, struct key *,
			      struct afs_fid *, struct afs_file_status *,
			      struct afs_callback *,
			      struct afs_cb_interest *);
extern void afs_zap_data(struct afs_vnode *);
extern int afs_validate(struct afs_vnode *, struct key *);
extern int afs_getattr(const struct path *, struct kstat *, u32, unsigned int);
extern int afs_setattr(struct dentry *, struct iattr *);
extern void afs_evict_inode(struct inode *);
extern int afs_drop_inode(struct inode *);

/*
 * main.c
 */
extern struct workqueue_struct *afs_wq;

static inline struct afs_net *afs_d2net(struct dentry *dentry)
{
	return &__afs_net;
}

static inline struct afs_net *afs_i2net(struct inode *inode)
{
	return &__afs_net;
}

static inline struct afs_net *afs_v2net(struct afs_vnode *vnode)
{
	return &__afs_net;
}

static inline struct afs_net *afs_sock2net(struct sock *sk)
{
	return &__afs_net;
}

static inline struct afs_net *afs_get_net(struct afs_net *net)
{
	return net;
}

static inline void afs_put_net(struct afs_net *net)
{
}

/*
 * misc.c
 */
extern int afs_abort_to_error(u32);

/*
 * mntpt.c
 */
extern const struct inode_operations afs_mntpt_inode_operations;
extern const struct inode_operations afs_autocell_inode_operations;
extern const struct file_operations afs_mntpt_file_operations;

extern struct vfsmount *afs_d_automount(struct path *);
extern void afs_mntpt_kill_timer(void);

/*
 * netdevices.c
 */
extern int afs_get_ipv4_interfaces(struct afs_interface *, size_t, bool);

/*
 * proc.c
 */
extern int __net_init afs_proc_init(struct afs_net *);
extern void __net_exit afs_proc_cleanup(struct afs_net *);
extern int afs_proc_cell_setup(struct afs_net *, struct afs_cell *);
extern void afs_proc_cell_remove(struct afs_net *, struct afs_cell *);

/*
 * rotate.c
 */
extern bool afs_begin_vnode_operation(struct afs_fs_cursor *, struct afs_vnode *,
				      struct key *);
extern bool afs_select_fileserver(struct afs_fs_cursor *);
extern bool afs_select_current_fileserver(struct afs_fs_cursor *);
extern int afs_end_vnode_operation(struct afs_fs_cursor *);

/*
 * rxrpc.c
 */
extern struct workqueue_struct *afs_async_calls;

extern int __net_init afs_open_socket(struct afs_net *);
extern void __net_exit afs_close_socket(struct afs_net *);
extern void afs_charge_preallocation(struct work_struct *);
extern void afs_put_call(struct afs_call *);
extern int afs_queue_call_work(struct afs_call *);
extern long afs_make_call(struct afs_addr_cursor *, struct afs_call *, gfp_t, bool);
extern struct afs_call *afs_alloc_flat_call(struct afs_net *,
					    const struct afs_call_type *,
					    size_t, size_t);
extern void afs_flat_call_destructor(struct afs_call *);
extern void afs_send_empty_reply(struct afs_call *);
extern void afs_send_simple_reply(struct afs_call *, const void *, size_t);
extern int afs_extract_data(struct afs_call *, void *, size_t, bool);

static inline int afs_transfer_reply(struct afs_call *call)
{
	return afs_extract_data(call, call->buffer, call->reply_max, false);
}

/*
 * security.c
 */
extern void afs_put_permits(struct afs_permits *);
extern void afs_clear_permits(struct afs_vnode *);
extern void afs_cache_permit(struct afs_vnode *, struct key *, unsigned int);
extern void afs_zap_permits(struct rcu_head *);
extern struct key *afs_request_key(struct afs_cell *);
extern int afs_permission(struct inode *, int);
extern void __exit afs_clean_up_permit_cache(void);

/*
 * server.c
 */
extern spinlock_t afs_server_peer_lock;

static inline struct afs_server *afs_get_server(struct afs_server *server)
{
	atomic_inc(&server->usage);
	return server;
}

extern struct afs_server *afs_find_server(struct afs_net *,
					  const struct sockaddr_rxrpc *);
extern struct afs_server *afs_find_server_by_uuid(struct afs_net *, const uuid_t *);
extern struct afs_server *afs_lookup_server(struct afs_cell *, struct key *, const uuid_t *);
extern void afs_put_server(struct afs_net *, struct afs_server *);
extern void afs_manage_servers(struct work_struct *);
extern void afs_servers_timer(struct timer_list *);
extern void __net_exit afs_purge_servers(struct afs_net *);
extern bool afs_probe_fileserver(struct afs_fs_cursor *);
extern bool afs_check_server_record(struct afs_fs_cursor *, struct afs_server *);

/*
 * server_list.c
 */
static inline struct afs_server_list *afs_get_serverlist(struct afs_server_list *slist)
{
	refcount_inc(&slist->usage);
	return slist;
}

extern void afs_put_serverlist(struct afs_net *, struct afs_server_list *);
extern struct afs_server_list *afs_alloc_server_list(struct afs_cell *, struct key *,
						     struct afs_vldb_entry *,
						     u8);
extern bool afs_annotate_server_list(struct afs_server_list *, struct afs_server_list *);

/*
 * super.c
 */
extern int __init afs_fs_init(void);
extern void __exit afs_fs_exit(void);

/*
 * vlclient.c
 */
extern struct afs_vldb_entry *afs_vl_get_entry_by_name_u(struct afs_net *,
							 struct afs_addr_cursor *,
							 struct key *, const char *, int);
extern struct afs_addr_list *afs_vl_get_addrs_u(struct afs_net *, struct afs_addr_cursor *,
						struct key *, const uuid_t *);

/*
 * volume.c
 */
static inline struct afs_volume *__afs_get_volume(struct afs_volume *volume)
{
	if (volume)
		atomic_inc(&volume->usage);
	return volume;
}

extern struct afs_volume *afs_create_volume(struct afs_mount_params *);
extern void afs_activate_volume(struct afs_volume *);
extern void afs_deactivate_volume(struct afs_volume *);
extern void afs_put_volume(struct afs_cell *, struct afs_volume *);
extern int afs_check_volume_status(struct afs_volume *, struct key *);

/*
 * write.c
 */
extern int afs_set_page_dirty(struct page *);
extern void afs_put_writeback(struct afs_writeback *);
extern int afs_write_begin(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata);
extern int afs_write_end(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned copied,
			struct page *page, void *fsdata);
extern int afs_writepage(struct page *, struct writeback_control *);
extern int afs_writepages(struct address_space *, struct writeback_control *);
extern void afs_pages_written_back(struct afs_vnode *, struct afs_call *);
extern ssize_t afs_file_write(struct kiocb *, struct iov_iter *);
extern int afs_writeback_all(struct afs_vnode *);
extern int afs_flush(struct file *, fl_owner_t);
extern int afs_fsync(struct file *, loff_t, loff_t, int);

/*
 * xattr.c
 */
extern const struct xattr_handler *afs_xattr_handlers[];
extern ssize_t afs_listxattr(struct dentry *, char *, size_t);


/*
 * Miscellaneous inline functions.
 */
static inline struct afs_vnode *AFS_FS_I(struct inode *inode)
{
	return container_of(inode, struct afs_vnode, vfs_inode);
}

static inline struct inode *AFS_VNODE_TO_I(struct afs_vnode *vnode)
{
	return &vnode->vfs_inode;
}

static inline void afs_vnode_commit_status(struct afs_fs_cursor *fc,
					   struct afs_vnode *vnode,
					   unsigned int cb_break)
{
	if (fc->ac.error == 0)
		afs_cache_permit(vnode, fc->key, cb_break);
}

static inline void afs_check_for_remote_deletion(struct afs_fs_cursor *fc,
						 struct afs_vnode *vnode)
{
	if (fc->ac.error == -ENOENT) {
		set_bit(AFS_VNODE_DELETED, &vnode->flags);
		afs_break_callback(vnode);
	}
}


/*****************************************************************************/
/*
 * debug tracing
 */
#include <trace/events/afs.h>

extern unsigned afs_debug;

#define dbgprintk(FMT,...) \
	printk("[%-6.6s] "FMT"\n", current->comm ,##__VA_ARGS__)

#define kenter(FMT,...)	dbgprintk("==> %s("FMT")",__func__ ,##__VA_ARGS__)
#define kleave(FMT,...)	dbgprintk("<== %s()"FMT"",__func__ ,##__VA_ARGS__)
#define kdebug(FMT,...)	dbgprintk("    "FMT ,##__VA_ARGS__)


#if defined(__KDEBUG)
#define _enter(FMT,...)	kenter(FMT,##__VA_ARGS__)
#define _leave(FMT,...)	kleave(FMT,##__VA_ARGS__)
#define _debug(FMT,...)	kdebug(FMT,##__VA_ARGS__)

#elif defined(CONFIG_AFS_DEBUG)
#define AFS_DEBUG_KENTER	0x01
#define AFS_DEBUG_KLEAVE	0x02
#define AFS_DEBUG_KDEBUG	0x04

#define _enter(FMT,...)					\
do {							\
	if (unlikely(afs_debug & AFS_DEBUG_KENTER))	\
		kenter(FMT,##__VA_ARGS__);		\
} while (0)

#define _leave(FMT,...)					\
do {							\
	if (unlikely(afs_debug & AFS_DEBUG_KLEAVE))	\
		kleave(FMT,##__VA_ARGS__);		\
} while (0)

#define _debug(FMT,...)					\
do {							\
	if (unlikely(afs_debug & AFS_DEBUG_KDEBUG))	\
		kdebug(FMT,##__VA_ARGS__);		\
} while (0)

#else
#define _enter(FMT,...)	no_printk("==> %s("FMT")",__func__ ,##__VA_ARGS__)
#define _leave(FMT,...)	no_printk("<== %s()"FMT"",__func__ ,##__VA_ARGS__)
#define _debug(FMT,...)	no_printk("    "FMT ,##__VA_ARGS__)
#endif

/*
 * debug assertion checking
 */
#if 1 // defined(__KDEBUGALL)

#define ASSERT(X)						\
do {								\
	if (unlikely(!(X))) {					\
		printk(KERN_ERR "\n");				\
		printk(KERN_ERR "AFS: Assertion failed\n");	\
		BUG();						\
	}							\
} while(0)

#define ASSERTCMP(X, OP, Y)						\
do {									\
	if (unlikely(!((X) OP (Y)))) {					\
		printk(KERN_ERR "\n");					\
		printk(KERN_ERR "AFS: Assertion failed\n");		\
		printk(KERN_ERR "%lu " #OP " %lu is false\n",		\
		       (unsigned long)(X), (unsigned long)(Y));		\
		printk(KERN_ERR "0x%lx " #OP " 0x%lx is false\n",	\
		       (unsigned long)(X), (unsigned long)(Y));		\
		BUG();							\
	}								\
} while(0)

#define ASSERTRANGE(L, OP1, N, OP2, H)					\
do {									\
	if (unlikely(!((L) OP1 (N)) || !((N) OP2 (H)))) {		\
		printk(KERN_ERR "\n");					\
		printk(KERN_ERR "AFS: Assertion failed\n");		\
		printk(KERN_ERR "%lu "#OP1" %lu "#OP2" %lu is false\n",	\
		       (unsigned long)(L), (unsigned long)(N),		\
		       (unsigned long)(H));				\
		printk(KERN_ERR "0x%lx "#OP1" 0x%lx "#OP2" 0x%lx is false\n", \
		       (unsigned long)(L), (unsigned long)(N),		\
		       (unsigned long)(H));				\
		BUG();							\
	}								\
} while(0)

#define ASSERTIF(C, X)						\
do {								\
	if (unlikely((C) && !(X))) {				\
		printk(KERN_ERR "\n");				\
		printk(KERN_ERR "AFS: Assertion failed\n");	\
		BUG();						\
	}							\
} while(0)

#define ASSERTIFCMP(C, X, OP, Y)					\
do {									\
	if (unlikely((C) && !((X) OP (Y)))) {				\
		printk(KERN_ERR "\n");					\
		printk(KERN_ERR "AFS: Assertion failed\n");		\
		printk(KERN_ERR "%lu " #OP " %lu is false\n",		\
		       (unsigned long)(X), (unsigned long)(Y));		\
		printk(KERN_ERR "0x%lx " #OP " 0x%lx is false\n",	\
		       (unsigned long)(X), (unsigned long)(Y));		\
		BUG();							\
	}								\
} while(0)

#else

#define ASSERT(X)				\
do {						\
} while(0)

#define ASSERTCMP(X, OP, Y)			\
do {						\
} while(0)

#define ASSERTRANGE(L, OP1, N, OP2, H)		\
do {						\
} while(0)

#define ASSERTIF(C, X)				\
do {						\
} while(0)

#define ASSERTIFCMP(C, X, OP, Y)		\
do {						\
} while(0)

#endif /* __KDEBUGALL */