fuse_i.h 25.3 KB
Newer Older
Miklos Szeredi's avatar
Miklos Szeredi committed
1
2
/*
  FUSE: Filesystem in Userspace
Miklos Szeredi's avatar
Miklos Szeredi committed
3
  Copyright (C) 2001-2008  Miklos Szeredi <miklos@szeredi.hu>
Miklos Szeredi's avatar
Miklos Szeredi committed
4
5
6
7
8

  This program can be distributed under the terms of the GNU GPL.
  See the file COPYING.
*/

Tejun Heo's avatar
Tejun Heo committed
9
10
11
#ifndef _FS_FUSE_I_H
#define _FS_FUSE_I_H

Miklos Szeredi's avatar
Miklos Szeredi committed
12
13
#include <linux/fuse.h>
#include <linux/fs.h>
14
#include <linux/mount.h>
Miklos Szeredi's avatar
Miklos Szeredi committed
15
16
17
18
19
#include <linux/wait.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/backing-dev.h>
20
#include <linux/mutex.h>
Miklos Szeredi's avatar
Miklos Szeredi committed
21
#include <linux/rwsem.h>
Tejun Heo's avatar
Tejun Heo committed
22
23
#include <linux/rbtree.h>
#include <linux/poll.h>
24
#include <linux/workqueue.h>
25
#include <linux/kref.h>
Seth Forshee's avatar
Seth Forshee committed
26
#include <linux/xattr.h>
27
#include <linux/pid_namespace.h>
28
#include <linux/refcount.h>
29
#include <linux/user_namespace.h>
Miklos Szeredi's avatar
Miklos Szeredi committed
30

31
32
33
34
35
/** Default max number of pages that can be used in a single read request */
#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32

/** Maximum of max_pages received in init_out */
#define FUSE_MAX_MAX_PAGES 256
36

Miklos Szeredi's avatar
Miklos Szeredi committed
37
38
39
/** Bias for fi->writectr, meaning new writepages must not be sent */
#define FUSE_NOWRITE INT_MIN

40
41
42
/** It could be as large as PATH_MAX, but would that have any uses? */
#define FUSE_NAME_MAX 1024

43
/** Number of dentries for each connection in the control filesystem */
44
#define FUSE_CTL_NUM_DENTRIES 5
45

46
47
48
/** Number of page pointers embedded in fuse_req */
#define FUSE_REQ_INLINE_PAGES 1

49
50
51
52
53
/** List of active connections */
extern struct list_head fuse_conn_list;

/** Global mutex protecting fuse_conn_list and the control filesystem */
extern struct mutex fuse_mutex;
Miklos Szeredi's avatar
Miklos Szeredi committed
54

55
56
57
58
/** Module parameters */
extern unsigned max_user_bgreq;
extern unsigned max_user_congthresh;

59
60
/* One forget request */
struct fuse_forget_link {
61
	struct fuse_forget_one forget_one;
62
63
64
	struct fuse_forget_link *next;
};

Miklos Szeredi's avatar
Miklos Szeredi committed
65
66
67
68
69
70
71
72
73
/** FUSE inode */
struct fuse_inode {
	/** Inode data */
	struct inode inode;

	/** Unique ID, which identifies the inode between userspace
	 * and kernel */
	u64 nodeid;

74
75
76
	/** Number of lookups on this inode */
	u64 nlookup;

77
	/** The request used for sending the FORGET message */
78
	struct fuse_forget_link *forget;
79

Miklos Szeredi's avatar
Miklos Szeredi committed
80
	/** Time in jiffies until the file attributes are valid */
Miklos Szeredi's avatar
Miklos Szeredi committed
81
	u64 i_time;
82

83
84
85
	/* Which attributes are invalid */
	u32 inval_mask;

86
87
	/** The sticky bit in inode->i_mode may have been removed, so
	    preserve the original mode */
Al Viro's avatar
Al Viro committed
88
	umode_t orig_i_mode;
89

90
91
92
	/** 64 bit inode number */
	u64 orig_ino;

93
94
	/** Version of last attribute change */
	u64 attr_version;
95

96
97
98
99
100
	union {
		/* Write related fields (regular file only) */
		struct {
			/* Files usable in writepage.  Protected by fc->lock */
			struct list_head write_files;
Miklos Szeredi's avatar
Miklos Szeredi committed
101

102
103
			/* Writepages pending on truncate or fsync */
			struct list_head queued_writes;
Miklos Szeredi's avatar
Miklos Szeredi committed
104

105
106
107
			/* Number of sent writes, a negative bias
			 * (FUSE_NOWRITE) means more writes are blocked */
			int writectr;
Miklos Szeredi's avatar
Miklos Szeredi committed
108

109
110
			/* Waitq for writepage completion */
			wait_queue_head_t page_waitq;
Miklos Szeredi's avatar
Miklos Szeredi committed
111

112
113
114
			/* List of writepage requestst (pending or sent) */
			struct list_head writepages;
		};
115

116
117
118
119
		/* readdir cache (directory only) */
		struct {
			/* true if fully cached */
			bool cached;
Miklos Szeredi's avatar
Miklos Szeredi committed
120

121
122
			/* size of cache */
			loff_t size;
Miklos Szeredi's avatar
Miklos Szeredi committed
123

124
125
			/* position at end of cache (position of next entry) */
			loff_t pos;
Miklos Szeredi's avatar
Miklos Szeredi committed
126

127
128
			/* version of the cache */
			u64 version;
129

130
131
132
			/* modification time of directory when cache was
			 * started */
			struct timespec64 mtime;
133

134
135
			/* iversion of directory when cache was started */
			u64 iversion;
136

137
138
139
140
			/* protects above fields */
			spinlock_t lock;
		} rdc;
	};
Miklos Szeredi's avatar
Miklos Szeredi committed
141

142
143
	/** Miscellaneous bits describing inode state */
	unsigned long state;
144
145
146

	/** Lock for serializing lookup and readdir for back compatibility*/
	struct mutex mutex;
147
148
149
150
151
152
};

/** FUSE inode state bits */
enum {
	/** Advise readdirplus  */
	FUSE_I_ADVISE_RDPLUS,
153
154
	/** Initialized with readdirplus */
	FUSE_I_INIT_RDPLUS,
155
156
	/** An operation changing file size is in progress  */
	FUSE_I_SIZE_UNSTABLE,
Miklos Szeredi's avatar
Miklos Szeredi committed
157
158
};

159
160
struct fuse_conn;

161
162
/** FUSE specific file data */
struct fuse_file {
163
164
165
	/** Fuse connection for this file */
	struct fuse_conn *fc;

166
	/** Request reserved for flush and release */
167
	struct fuse_req *reserved_req;
168

Tejun Heo's avatar
Tejun Heo committed
169
170
171
	/** Kernel file handle guaranteed to be unique */
	u64 kh;

172
173
	/** File handle used by userspace */
	u64 fh;
174

175
176
177
	/** Node id of this file */
	u64 nodeid;

178
	/** Refcount */
179
	refcount_t count;
180

181
182
183
	/** FOPEN_* flags returned by open */
	u32 open_flags;

184
185
	/** Entry on inode's write_files list */
	struct list_head write_entry;
Tejun Heo's avatar
Tejun Heo committed
186

187
188
189
190
191
192
193
194
195
196
197
198
199
	/* Readdir related */
	struct {
		/*
		 * Protects below fields against (crazy) parallel readdir on
		 * same open file.  Uncontended in the normal case.
		 */
		struct mutex lock;

		/* Dir stream position */
		loff_t pos;

		/* Offset in cache */
		loff_t cache_off;
200
201
202
203

		/* Version of cache we are reading */
		u64 version;

204
205
	} readdir;

Tejun Heo's avatar
Tejun Heo committed
206
207
208
209
210
	/** RB node to be linked on fuse_conn->polled_files */
	struct rb_node polled_node;

	/** Wait queue head for poll */
	wait_queue_head_t poll_wait;
Miklos Szeredi's avatar
Miklos Szeredi committed
211
212
213

	/** Has flock been performed on this file? */
	bool flock:1;
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
/** One input argument of a request */
struct fuse_in_arg {
	unsigned size;
	const void *value;
};

/** The request input */
struct fuse_in {
	/** The request header */
	struct fuse_in_header h;

	/** True if the data for the last argument is in req->pages */
	unsigned argpages:1;

	/** Number of arguments */
	unsigned numargs;

	/** Array of arguments */
	struct fuse_in_arg args[3];
};

/** One output argument of a request */
struct fuse_arg {
	unsigned size;
	void *value;
};

/** The request output */
struct fuse_out {
	/** Header returned from userspace */
	struct fuse_out_header h;

248
249
250
251
252
	/*
	 * The following bitfields are not changed during the request
	 * processing
	 */

253
254
255
256
257
258
259
260
261
262
	/** Last argument is variable length (can be shorter than
	    arg->size) */
	unsigned argvar:1;

	/** Last argument is a list of pages to copy data to */
	unsigned argpages:1;

	/** Zero partially or not copied pages */
	unsigned page_zeroing:1;

263
264
265
	/** Pages may be replaced with new ones */
	unsigned page_replace:1;

266
267
268
269
	/** Number or arguments */
	unsigned numargs;

	/** Array of arguments */
Miklos Szeredi's avatar
Miklos Szeredi committed
270
	struct fuse_arg args[2];
271
272
};

273
274
275
276
277
278
/** FUSE page descriptor */
struct fuse_page_desc {
	unsigned int length;
	unsigned int offset;
};

279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
struct fuse_args {
	struct {
		struct {
			uint32_t opcode;
			uint64_t nodeid;
		} h;
		unsigned numargs;
		struct fuse_in_arg args[3];

	} in;
	struct {
		unsigned argvar:1;
		unsigned numargs;
		struct fuse_arg args[2];
	} out;
};

#define FUSE_ARGS(args) struct fuse_args args = {}

Maxim Patlasov's avatar
Maxim Patlasov committed
298
299
/** The request IO state (for asynchronous processing) */
struct fuse_io_priv {
300
	struct kref refcnt;
Maxim Patlasov's avatar
Maxim Patlasov committed
301
302
303
304
305
306
307
	int async;
	spinlock_t lock;
	unsigned reqs;
	ssize_t bytes;
	size_t size;
	__u64 offset;
	bool write;
308
	bool should_dirty;
Maxim Patlasov's avatar
Maxim Patlasov committed
309
310
	int err;
	struct kiocb *iocb;
311
	struct completion *done;
312
	bool blocking;
Maxim Patlasov's avatar
Maxim Patlasov committed
313
314
};

315
#define FUSE_IO_PRIV_SYNC(i) \
316
{					\
317
	.refcnt = KREF_INIT(1),		\
318
	.async = 0,			\
319
	.iocb = i,			\
320
321
}

Miklos Szeredi's avatar
Miklos Szeredi committed
322
323
324
325
326
327
328
329
330
331
/**
 * Request flags
 *
 * FR_ISREPLY:		set if the request has reply
 * FR_FORCE:		force sending of the request even if interrupted
 * FR_BACKGROUND:	request is sent in the background
 * FR_WAITING:		request is counted as "waiting"
 * FR_ABORTED:		the request was aborted
 * FR_INTERRUPTED:	the request has been interrupted
 * FR_LOCKED:		data is being copied to/from the request
Miklos Szeredi's avatar
Miklos Szeredi committed
332
333
334
 * FR_PENDING:		request is not yet in userspace
 * FR_SENT:		request is in userspace, waiting for an answer
 * FR_FINISHED:		request is finished
335
 * FR_PRIVATE:		request is on private list
Miklos Szeredi's avatar
Miklos Szeredi committed
336
337
338
339
340
341
342
343
344
 */
enum fuse_req_flag {
	FR_ISREPLY,
	FR_FORCE,
	FR_BACKGROUND,
	FR_WAITING,
	FR_ABORTED,
	FR_INTERRUPTED,
	FR_LOCKED,
Miklos Szeredi's avatar
Miklos Szeredi committed
345
346
347
	FR_PENDING,
	FR_SENT,
	FR_FINISHED,
348
	FR_PRIVATE,
Miklos Szeredi's avatar
Miklos Szeredi committed
349
350
};

351
352
/**
 * A request to the client
353
354
355
356
 *
 * .waitq.lock protects the following fields:
 *   - FR_ABORTED
 *   - FR_LOCKED (may also be modified under fc->lock, tested under both)
357
358
 */
struct fuse_req {
359
360
	/** This can be on either pending processing or io lists in
	    fuse_conn */
361
362
	struct list_head list;

363
364
365
	/** Entry on the interrupts list  */
	struct list_head intr_entry;

366
	/** refcount */
367
	refcount_t count;
368

Miklos Szeredi's avatar
Miklos Szeredi committed
369
370
	/* Request flags, updated with test/set/clear_bit() */
	unsigned long flags;
371

372
373
374
375
376
377
378
379
380
381
382
	/** The request input */
	struct fuse_in in;

	/** The request output */
	struct fuse_out out;

	/** Used to wake up the task waiting for completion of request*/
	wait_queue_head_t waitq;

	/** Data for asynchronous requests */
	union {
383
		struct {
384
385
			struct fuse_release_in in;
			struct inode *inode;
386
		} release;
387
388
		struct fuse_init_in init_in;
		struct fuse_init_out init_out;
389
		struct cuse_init_in cuse_init_in;
390
391
392
393
		struct {
			struct fuse_read_in in;
			u64 attr_ver;
		} read;
394
395
396
		struct {
			struct fuse_write_in in;
			struct fuse_write_out out;
397
			struct fuse_req *next;
398
		} write;
Miklos Szeredi's avatar
Miklos Szeredi committed
399
		struct fuse_notify_retrieve_in retrieve_in;
400
401
402
	} misc;

	/** page vector */
403
404
	struct page **pages;

405
406
407
	/** page-descriptor vector */
	struct fuse_page_desc *page_descs;

408
409
410
411
412
	/** size of the 'pages' array */
	unsigned max_pages;

	/** inline page vector */
	struct page *inline_pages[FUSE_REQ_INLINE_PAGES];
413

414
415
416
	/** inline page-descriptor vector */
	struct fuse_page_desc inline_page_descs[FUSE_REQ_INLINE_PAGES];

417
418
419
420
	/** number of pages in vector */
	unsigned num_pages;

	/** File used in the request (or NULL) */
421
	struct fuse_file *ff;
422

Miklos Szeredi's avatar
Miklos Szeredi committed
423
424
425
	/** Inode used in the request or NULL */
	struct inode *inode;

Maxim Patlasov's avatar
Maxim Patlasov committed
426
427
428
	/** AIO control block */
	struct fuse_io_priv *io;

Miklos Szeredi's avatar
Miklos Szeredi committed
429
430
431
	/** Link on fi->writepages */
	struct list_head writepages_entry;

432
433
	/** Request completion callback */
	void (*end)(struct fuse_conn *, struct fuse_req *);
434
435
436

	/** Request is stolen from fuse_file->reserved_req */
	struct file *stolen_file;
437
438
};

439
struct fuse_iqueue {
440
441
442
	/** Connection established */
	unsigned connected;

443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
	/** Readers of the connection are waiting on this */
	wait_queue_head_t waitq;

	/** The next unique request id */
	u64 reqctr;

	/** The list of pending requests */
	struct list_head pending;

	/** Pending interrupts */
	struct list_head interrupts;

	/** Queue of pending forgets */
	struct fuse_forget_link forget_list_head;
	struct fuse_forget_link *forget_list_tail;

	/** Batching of FORGET requests (positive indicates FORGET batch) */
	int forget_batch;

	/** O_ASYNC requests */
	struct fasync_struct *fasync;
};

466
467
468
#define FUSE_PQ_HASH_BITS 8
#define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS)

469
struct fuse_pqueue {
470
471
472
	/** Connection established */
	unsigned connected;

Miklos Szeredi's avatar
Miklos Szeredi committed
473
474
475
	/** Lock protecting accessess to  members of this structure */
	spinlock_t lock;

476
477
	/** Hash table of requests being processed */
	struct list_head *processing;
478
479
480
481
482

	/** The list of requests under I/O */
	struct list_head io;
};

483
484
485
486
487
488
489
/**
 * Fuse device instance
 */
struct fuse_dev {
	/** Fuse connection for this device */
	struct fuse_conn *fc;

490
491
492
	/** Processing queue */
	struct fuse_pqueue pq;

493
494
495
496
	/** list entry on fc->devices */
	struct list_head entry;
};

Miklos Szeredi's avatar
Miklos Szeredi committed
497
498
499
500
501
502
503
504
/**
 * A Fuse connection.
 *
 * This structure is created, when the filesystem is mounted, and is
 * destroyed, when the client device is closed and the filesystem is
 * unmounted.
 */
struct fuse_conn {
505
506
507
	/** Lock protecting accessess to  members of this structure */
	spinlock_t lock;

508
	/** Refcount */
509
	refcount_t count;
510

511
512
513
	/** Number of fuse_dev's */
	atomic_t dev_count;

Al Viro's avatar
Al Viro committed
514
515
	struct rcu_head rcu;

Miklos Szeredi's avatar
Miklos Szeredi committed
516
	/** The user id for this mount */
517
	kuid_t user_id;
Miklos Szeredi's avatar
Miklos Szeredi committed
518

519
	/** The group id for this mount */
520
	kgid_t group_id;
521

522
523
524
	/** The pid namespace for this mount */
	struct pid_namespace *pid_ns;

525
526
527
	/** The user namespace for this mount */
	struct user_namespace *user_ns;

528
529
530
	/** Maximum read size */
	unsigned max_read;

Miklos Szeredi's avatar
Miklos Szeredi committed
531
532
533
	/** Maximum write size */
	unsigned max_write;

534
535
536
	/** Maxmum number of pages that can be used in a single request */
	unsigned int max_pages;

537
538
	/** Input queue */
	struct fuse_iqueue iq;
539

Tejun Heo's avatar
Tejun Heo committed
540
541
542
	/** The next unique kernel file handle */
	u64 khctr;

Tejun Heo's avatar
Tejun Heo committed
543
544
545
	/** rbtree of fuse_files waiting for poll events indexed by ph */
	struct rb_root polled_files;

546
547
548
549
550
551
	/** Maximum number of outstanding background requests */
	unsigned max_background;

	/** Number of background requests at which congestion starts */
	unsigned congestion_threshold;

552
553
554
	/** Number of requests currently in the background */
	unsigned num_background;

555
556
557
558
559
560
	/** Number of background requests currently queued for userspace */
	unsigned active_background;

	/** The list of background requests set aside for later queuing */
	struct list_head bg_queue;

Kirill Tkhai's avatar
Kirill Tkhai committed
561
562
563
564
	/** Protects: max_background, congestion_threshold, num_background,
	 * active_background, bg_queue, blocked */
	spinlock_t bg_lock;

565
566
567
568
	/** Flag indicating that INIT reply has been received. Allocating
	 * any fuse request will be suspended until the flag is set */
	int initialized;

569
570
571
572
573
574
575
	/** Flag indicating if connection is blocked.  This will be
	    the case before the INIT reply is received, and if there
	    are too many outstading backgrounds requests */
	int blocked;

	/** waitq for blocked connection */
	wait_queue_head_t blocked_waitq;
576
577
578

	/** waitq for reserved requests */
	wait_queue_head_t reserved_req_waitq;
579

580
581
	/** Connection established, cleared on umount, connection
	    abort and device release */
582
	unsigned connected;
Miklos Szeredi's avatar
Miklos Szeredi committed
583

584
585
586
	/** Connection aborted via sysfs */
	bool aborted;

587
588
589
	/** Connection failed (version mismatch).  Cannot race with
	    setting other bitfields since it is only set once in INIT
	    reply, before any other request, and never cleared */
Miklos Szeredi's avatar
Miklos Szeredi committed
590
	unsigned conn_error:1;
591

592
	/** Connection successful.  Only set in INIT */
Miklos Szeredi's avatar
Miklos Szeredi committed
593
	unsigned conn_init:1;
594

595
	/** Do readpages asynchronously?  Only set in INIT */
Miklos Szeredi's avatar
Miklos Szeredi committed
596
	unsigned async_read:1;
597

598
599
600
	/** Return an unique read error after abort.  Only set in INIT */
	unsigned abort_err:1;

601
	/** Do not send separate SETATTR request before open(O_TRUNC)  */
Miklos Szeredi's avatar
Miklos Szeredi committed
602
	unsigned atomic_o_trunc:1;
603

604
	/** Filesystem supports NFS exporting.  Only set in INIT */
Miklos Szeredi's avatar
Miklos Szeredi committed
605
	unsigned export_support:1;
606

607
608
609
	/** write-back cache policy (default is write-through) */
	unsigned writeback_cache:1;

610
611
612
	/** allow parallel lookups and readdir (default is serialized) */
	unsigned parallel_dirops:1;

613
614
615
	/** handle fs handles killing suid/sgid/cap on write/chown/trunc */
	unsigned handle_killpriv:1;

616
617
618
619
620
	/*
	 * The following bitfields are only for optimization purposes
	 * and hence races in setting them will not cause malfunction
	 */

621
622
623
	/** Is open/release not implemented by fs? */
	unsigned no_open:1;

624
	/** Is fsync not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
625
	unsigned no_fsync:1;
626

627
	/** Is fsyncdir not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
628
	unsigned no_fsyncdir:1;
629

630
	/** Is flush not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
631
	unsigned no_flush:1;
632

633
	/** Is setxattr not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
634
	unsigned no_setxattr:1;
635
636

	/** Is getxattr not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
637
	unsigned no_getxattr:1;
638
639

	/** Is listxattr not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
640
	unsigned no_listxattr:1;
641
642

	/** Is removexattr not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
643
	unsigned no_removexattr:1;
644

Miklos Szeredi's avatar
Miklos Szeredi committed
645
	/** Are posix file locking primitives not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
646
	unsigned no_lock:1;
647

Miklos Szeredi's avatar
Miklos Szeredi committed
648
	/** Is access not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
649
	unsigned no_access:1;
Miklos Szeredi's avatar
Miklos Szeredi committed
650

651
	/** Is create not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
652
	unsigned no_create:1;
653

654
	/** Is interrupt not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
655
	unsigned no_interrupt:1;
656

657
	/** Is bmap not implemented by fs? */
Miklos Szeredi's avatar
Miklos Szeredi committed
658
	unsigned no_bmap:1;
659

Tejun Heo's avatar
Tejun Heo committed
660
661
662
	/** Is poll not implemented by fs? */
	unsigned no_poll:1;

663
	/** Do multi-page cached writes */
Miklos Szeredi's avatar
Miklos Szeredi committed
664
	unsigned big_writes:1;
665

666
667
668
	/** Don't apply umask to creation modes */
	unsigned dont_mask:1;

Miklos Szeredi's avatar
Miklos Szeredi committed
669
670
671
	/** Are BSD file locking primitives not implemented by fs? */
	unsigned no_flock:1;

672
673
674
	/** Is fallocate not implemented by fs? */
	unsigned no_fallocate:1;

Miklos Szeredi's avatar
Miklos Szeredi committed
675
676
677
	/** Is rename with flags implemented by fs? */
	unsigned no_rename2:1;

678
679
680
	/** Use enhanced/automatic page cache invalidation. */
	unsigned auto_inval_data:1;

681
	/** Does the filesystem support readdirplus? */
682
683
	unsigned do_readdirplus:1;

684
685
686
	/** Does the filesystem want adaptive readdirplus? */
	unsigned readdirplus_auto:1;

687
688
689
	/** Does the filesystem support asynchronous direct-IO submission? */
	unsigned async_dio:1;

690
691
692
	/** Is lseek not implemented by fs? */
	unsigned no_lseek:1;

Seth Forshee's avatar
Seth Forshee committed
693
694
695
	/** Does the filesystem support posix acls? */
	unsigned posix_acl:1;

Miklos Szeredi's avatar
Miklos Szeredi committed
696
697
698
699
700
701
	/** Check permissions based on the file mode or not? */
	unsigned default_permissions:1;

	/** Allow other than the mounter user to access the filesystem ? */
	unsigned allow_other:1;

702
703
704
	/** Does the filesystem support copy_file_range? */
	unsigned no_copy_file_range:1;

705
706
707
	/** The number of requests waiting for completion */
	atomic_t num_waiting;

708
709
710
	/** Negotiated minor version */
	unsigned minor;

711
712
713
	/** Entry on the fuse_conn_list */
	struct list_head entry;

714
715
	/** Device ID from super block */
	dev_t dev;
716
717
718
719
720
721

	/** Dentries in the control filesystem */
	struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];

	/** number of dentries used in the above array */
	int ctl_ndents;
722

723
724
	/** Key for lock owner ID scrambling */
	u32 scramble_key[4];
725
726
727

	/** Reserved request for the DESTROY message */
	struct fuse_req *destroy_req;
728
729
730

	/** Version counter for attribute changes */
	u64 attr_version;
Tejun Heo's avatar
Tejun Heo committed
731
732
733

	/** Called on final put */
	void (*release)(struct fuse_conn *);
John Muir's avatar
John Muir committed
734
735
736
737
738
739

	/** Super block for this connection. */
	struct super_block *sb;

	/** Read/write semaphore to hold when accessing sb. */
	struct rw_semaphore killsb;
740
741
742

	/** List of device instances belonging to this connection */
	struct list_head devices;
Miklos Szeredi's avatar
Miklos Szeredi committed
743
744
745
746
};

static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
{
747
	return sb->s_fs_info;
Miklos Szeredi's avatar
Miklos Szeredi committed
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
}

static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
{
	return get_fuse_conn_super(inode->i_sb);
}

static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
{
	return container_of(inode, struct fuse_inode, inode);
}

static inline u64 get_node_id(struct inode *inode)
{
	return get_fuse_inode(inode)->nodeid;
}

Miklos Szeredi's avatar
Miklos Szeredi committed
765
766
767
768
769
static inline int invalid_nodeid(u64 nodeid)
{
	return !nodeid || nodeid == FUSE_ROOT_ID;
}

770
/** Device operations */
771
extern const struct file_operations fuse_dev_operations;
772

Al Viro's avatar
Al Viro committed
773
extern const struct dentry_operations fuse_dentry_operations;
774
extern const struct dentry_operations fuse_root_dentry_operations;
Miklos Szeredi's avatar
Miklos Szeredi committed
775

John Muir's avatar
John Muir committed
776
777
778
779
780
/**
 * Inode to nodeid comparison.
 */
int fuse_inode_eq(struct inode *inode, void *_nodeidp);

781
782
783
/**
 * Get a filled in inode
 */
Miklos Szeredi's avatar
Miklos Szeredi committed
784
struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
785
786
			int generation, struct fuse_attr *attr,
			u64 attr_valid, u64 attr_version);
787

Al Viro's avatar
Al Viro committed
788
int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name,
789
790
		     struct fuse_entry_out *outarg, struct inode **inode);

791
792
793
/**
 * Send FORGET command
 */
794
795
796
797
void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
		       u64 nodeid, u64 nlookup);

struct fuse_forget_link *fuse_alloc_forget(void);
798

799
800
801
/* Used by READDIRPLUS */
void fuse_force_forget(struct file *file, u64 nodeid);

802
/**
803
 * Initialize READ or READDIR request
804
 */
805
void fuse_read_fill(struct fuse_req *req, struct file *file,
806
		    loff_t pos, size_t count, int opcode);
807
808
809
810

/**
 * Send OPEN or OPENDIR request
 */
811
int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
812

Tejun Heo's avatar
Tejun Heo committed
813
struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
814
void fuse_file_free(struct fuse_file *ff);
815
void fuse_finish_open(struct inode *inode, struct file *file);
816

817
void fuse_sync_release(struct fuse_file *ff, int flags);
818

819
820
821
/**
 * Send RELEASE or RELEASEDIR request
 */
822
void fuse_release_common(struct file *file, int opcode);
823

824
825
826
/**
 * Send FSYNC or FSYNCDIR request
 */
827
828
int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
		      int datasync, int isdir);
829

Tejun Heo's avatar
Tejun Heo committed
830
831
832
833
834
835
/**
 * Notify poll wakeup
 */
int fuse_notify_poll_wakeup(struct fuse_conn *fc,
			    struct fuse_notify_poll_wakeup_out *outarg);

836
/**
Miklos Szeredi's avatar
Miklos Szeredi committed
837
 * Initialize file operations on a regular file
838
839
840
 */
void fuse_init_file_inode(struct inode *inode);

841
/**
Miklos Szeredi's avatar
Miklos Szeredi committed
842
 * Initialize inode operations on regular files and special files
843
844
845
846
 */
void fuse_init_common(struct inode *inode);

/**
Miklos Szeredi's avatar
Miklos Szeredi committed
847
 * Initialize inode and file operations on a directory
848
849
850
851
 */
void fuse_init_dir(struct inode *inode);

/**
Miklos Szeredi's avatar
Miklos Szeredi committed
852
 * Initialize inode operations on a symlink
853
854
855
856
857
858
 */
void fuse_init_symlink(struct inode *inode);

/**
 * Change attributes of an inode
 */
859
860
void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
			    u64 attr_valid, u64 attr_version);
861

Miklos Szeredi's avatar
Miklos Szeredi committed
862
863
864
void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
				   u64 attr_valid);

865
866
867
868
869
870
871
872
873
874
/**
 * Initialize the client device
 */
int fuse_dev_init(void);

/**
 * Cleanup the client device
 */
void fuse_dev_cleanup(void);

875
int fuse_ctl_init(void);
876
void __exit fuse_ctl_cleanup(void);
877

878
879
880
/**
 * Allocate a request
 */
881
struct fuse_req *fuse_request_alloc(unsigned npages);
882

883
struct fuse_req *fuse_request_alloc_nofs(unsigned npages);
Miklos Szeredi's avatar
Miklos Szeredi committed
884

Miklos Szeredi's avatar
Miklos Szeredi committed
885
886
887
888
bool fuse_req_realloc_pages(struct fuse_conn *fc, struct fuse_req *req,
			    gfp_t flags);


889
890
891
892
893
894
/**
 * Free a request
 */
void fuse_request_free(struct fuse_req *req);

/**
895
896
 * Get a request, may fail with -ENOMEM,
 * caller should specify # elements in req->pages[] explicitly
897
 */
898
struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages);
899
900
struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
					     unsigned npages);
901

902
903
904
905
906
/*
 * Increment reference count on request
 */
void __fuse_get_request(struct fuse_req *req);

907
908
909
/**
 * Gets a requests for a file operation, always succeeds
 */
910
911
struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
					     struct file *file);
912

913
/**
914
915
 * Decrement reference count of a request.  If count goes to zero free
 * the request.
916
917
918
919
 */
void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);

/**
920
 * Send a request (synchronous)
921
 */
922
void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);
923

924
925
926
927
928
/**
 * Simple request sending that does request allocation and freeing
 */
ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args);

929
930
931
/**
 * Send a request in the background
 */
932
void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req);
933
bool fuse_request_queue_background(struct fuse_conn *fc, struct fuse_req *req);
Miklos Szeredi's avatar
Miklos Szeredi committed
934

935
/* Abort all requests */
936
void fuse_abort_conn(struct fuse_conn *fc, bool is_abort);
937
void fuse_wait_aborted(struct fuse_conn *fc);
938

939
940
941
942
/**
 * Invalidate inode attributes
 */
void fuse_invalidate_attr(struct inode *inode);
943

Miklos Szeredi's avatar
Miklos Szeredi committed
944
945
void fuse_invalidate_entry_cache(struct dentry *entry);

946
947
void fuse_invalidate_atime(struct inode *inode);

Miklos Szeredi's avatar
Miklos Szeredi committed
948
949
950
u64 entry_attr_timeout(struct fuse_entry_out *o);
void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o);

951
952
953
954
955
/**
 * Acquire reference to fuse_conn
 */
struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);

956
957
958
/**
 * Initialize fuse_conn
 */
959
void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns);
960

961
962
963
964
965
/**
 * Release reference to fuse_conn
 */
void fuse_conn_put(struct fuse_conn *fc);

966
967
968
struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc);
void fuse_dev_free(struct fuse_dev *fud);

969
970
971
972
973
974
975
976
977
/**
 * Add connection to control filesystem
 */
int fuse_ctl_add_conn(struct fuse_conn *fc);

/**
 * Remove connection from control filesystem
 */
void fuse_ctl_remove_conn(struct fuse_conn *fc);
978
979
980
981
982

/**
 * Is file type valid?
 */
int fuse_valid_type(int m);
Miklos Szeredi's avatar
Miklos Szeredi committed
983
984

/**
985
 * Is current process allowed to perform filesystem operation?
Miklos Szeredi's avatar
Miklos Szeredi committed
986
 */
987
int fuse_allow_current_process(struct fuse_conn *fc);
988
989

u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
Miklos Szeredi's avatar
Miklos Szeredi committed
990

Seth Forshee's avatar
Seth Forshee committed
991
992
void fuse_update_ctime(struct inode *inode);

Miklos Szeredi's avatar
Miklos Szeredi committed
993
int fuse_update_attributes(struct inode *inode, struct file *file);
Miklos Szeredi's avatar
Miklos Szeredi committed
994
995
996
997
998

void fuse_flush_writepages(struct inode *inode);

void fuse_set_nowrite(struct inode *inode);
void fuse_release_nowrite(struct inode *inode);
999
1000

u64 fuse_get_attr_version(struct fuse_conn *fc);
Tejun Heo's avatar
Tejun Heo committed
1001

John Muir's avatar
John Muir committed
1002
1003
1004
1005
1006
1007
1008
1009
1010
/**
 * File-system tells the kernel to invalidate cache for the given node id.
 */
int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
			     loff_t offset, loff_t len);

/**
 * File-system tells the kernel to invalidate parent attributes and
 * the dentry matching parent/name.
1011
1012
1013
1014
1015
1016
 *
 * If the child_nodeid is non-zero and:
 *    - matches the inode number for the dentry matching parent/name,
 *    - is not a mount point
 *    - is a file or oan empty directory
 * then the dentry is unhashed (d_delete()).
John Muir's avatar
John Muir committed
1017
1018
 */
int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
1019
			     u64 child_nodeid, struct qstr *name);
John Muir's avatar
John Muir committed
1020

1021
1022
int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
		 bool isdir);
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033

/**
 * fuse_direct_io() flags
 */

/** If set, it is WRITE; otherwise - READ */
#define FUSE_DIO_WRITE (1 << 0)

/** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */
#define FUSE_DIO_CUSE  (1 << 1)

1034
1035
ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
		       loff_t *ppos, int flags);
1036
1037
long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
		   unsigned int flags);
1038
1039
long fuse_ioctl_common(struct file *file, unsigned int cmd,
		       unsigned long arg, unsigned int flags);
Al Viro's avatar
Al Viro committed
1040
__poll_t fuse_file_poll(struct file *file, poll_table *wait);
1041
1042
int fuse_dev_release(struct inode *inode, struct file *file);

1043
1044
bool fuse_write_update_size(struct inode *inode, loff_t pos);

1045
int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
Miklos Szeredi's avatar
Miklos Szeredi committed
1046
int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
Miklos Szeredi's avatar
Miklos Szeredi committed
1047

1048
int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
1049
1050
		    struct file *file);

1051
1052
void fuse_set_initialized(struct fuse_conn *fc);

1053
1054
void fuse_unlock_inode(struct inode *inode, bool locked);
bool fuse_lock_inode(struct inode *inode);
1055

Seth Forshee's avatar
Seth Forshee committed
1056
1057
1058
1059
int fuse_setxattr(struct inode *inode, const char *name, const void *value,
		  size_t size, int flags);
ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
		      size_t size);
Seth Forshee's avatar
Seth Forshee committed
1060
ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
Seth Forshee's avatar
Seth Forshee committed
1061
int fuse_removexattr(struct inode *inode, const char *name);
Seth Forshee's avatar
Seth Forshee committed
1062
extern const struct xattr_handler *fuse_xattr_handlers[];
Seth Forshee's avatar
Seth Forshee committed
1063
extern const struct xattr_handler *fuse_acl_xattr_handlers[];
1064
extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
Seth Forshee's avatar
Seth Forshee committed
1065
1066
1067
1068

struct posix_acl;
struct posix_acl *fuse_get_acl(struct inode *inode, int type);
int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
Seth Forshee's avatar
Seth Forshee committed
1069

Miklos Szeredi's avatar
Miklos Szeredi committed
1070
1071
1072
1073

/* readdir.c */
int fuse_readdir(struct file *file, struct dir_context *ctx);

Tejun Heo's avatar
Tejun Heo committed
1074
#endif /* _FS_FUSE_I_H */