1 /*
2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
4
5 This program can be distributed under the terms of the GNU GPL.
6 See the file COPYING.
7 */
8
9 #ifndef _FS_FUSE_I_H
10 #define _FS_FUSE_I_H
11
12 #include <linux/fuse.h>
13 #include <linux/fs.h>
14 #include <linux/mount.h>
15 #include <linux/wait.h>
16 #include <linux/list.h>
17 #include <linux/spinlock.h>
18 #include <linux/mm.h>
19 #include <linux/backing-dev.h>
20 #include <linux/mutex.h>
21 #include <linux/rwsem.h>
22 #include <linux/rbtree.h>
23 #include <linux/poll.h>
24 #include <linux/workqueue.h>
25 #include <linux/kref.h>
26 #include <linux/xattr.h>
27 #include <linux/pid_namespace.h>
28 #include <linux/refcount.h>
29
30 /** Max number of pages that can be used in a single read request */
31 #define FUSE_MAX_PAGES_PER_REQ 32
32
33 /** Bias for fi->writectr, meaning new writepages must not be sent */
34 #define FUSE_NOWRITE INT_MIN
35
36 /** It could be as large as PATH_MAX, but would that have any uses? */
37 #define FUSE_NAME_MAX 1024
38
39 /** Number of dentries for each connection in the control filesystem */
40 #define FUSE_CTL_NUM_DENTRIES 5
41
42 /** Number of page pointers embedded in fuse_req */
43 #define FUSE_REQ_INLINE_PAGES 1
44
45 /** List of active connections */
46 extern struct list_head fuse_conn_list;
47
48 /** Global mutex protecting fuse_conn_list and the control filesystem */
49 extern struct mutex fuse_mutex;
50
51 /** Module parameters */
52 extern unsigned max_user_bgreq;
53 extern unsigned max_user_congthresh;
54
55 /* One forget request */
56 struct fuse_forget_link {
57 struct fuse_forget_one forget_one;
58 struct fuse_forget_link *next;
59 };
60
61 /** FUSE inode */
62 struct fuse_inode {
63 /** Inode data */
64 struct inode inode;
65
66 /** Unique ID, which identifies the inode between userspace
67 * and kernel */
68 u64 nodeid;
69
70 /** Number of lookups on this inode */
71 u64 nlookup;
72
73 /** The request used for sending the FORGET message */
74 struct fuse_forget_link *forget;
75
76 /** Time in jiffies until the file attributes are valid */
77 u64 i_time;
78
79 /** The sticky bit in inode->i_mode may have been removed, so
80 preserve the original mode */
81 umode_t orig_i_mode;
82
83 /** 64 bit inode number */
84 u64 orig_ino;
85
86 /** Version of last attribute change */
87 u64 attr_version;
88
89 /** Files usable in writepage. Protected by fc->lock */
90 struct list_head write_files;
91
92 /** Writepages pending on truncate or fsync */
93 struct list_head queued_writes;
94
95 /** Number of sent writes, a negative bias (FUSE_NOWRITE)
96 * means more writes are blocked */
97 int writectr;
98
99 /** Waitq for writepage completion */
100 wait_queue_head_t page_waitq;
101
102 /** List of writepage requestst (pending or sent) */
103 struct list_head writepages;
104
105 /** Miscellaneous bits describing inode state */
106 unsigned long state;
107
108 /** Lock for serializing lookup and readdir for back compatibility*/
109 struct mutex mutex;
110 };
111
112 /** FUSE inode state bits */
113 enum {
114 /** Advise readdirplus */
115 FUSE_I_ADVISE_RDPLUS,
116 /** Initialized with readdirplus */
117 FUSE_I_INIT_RDPLUS,
118 /** An operation changing file size is in progress */
119 FUSE_I_SIZE_UNSTABLE,
120 };
121
122 struct fuse_conn;
123
124 /** FUSE specific file data */
125 struct fuse_file {
126 /** Fuse connection for this file */
127 struct fuse_conn *fc;
128
129 /** Request reserved for flush and release */
130 struct fuse_req *reserved_req;
131
132 /** Kernel file handle guaranteed to be unique */
133 u64 kh;
134
135 /** File handle used by userspace */
136 u64 fh;
137
138 /** Node id of this file */
139 u64 nodeid;
140
141 /** Refcount */
142 refcount_t count;
143
144 /** FOPEN_* flags returned by open */
145 u32 open_flags;
146
147 /** Entry on inode's write_files list */
148 struct list_head write_entry;
149
150 /** RB node to be linked on fuse_conn->polled_files */
151 struct rb_node polled_node;
152
153 /** Wait queue head for poll */
154 wait_queue_head_t poll_wait;
155
156 /** Has flock been performed on this file? */
157 bool flock:1;
158 };
159
160 /** One input argument of a request */
161 struct fuse_in_arg {
162 unsigned size;
163 const void *value;
164 };
165
166 /** The request input */
167 struct fuse_in {
168 /** The request header */
169 struct fuse_in_header h;
170
171 /** True if the data for the last argument is in req->pages */
172 unsigned argpages:1;
173
174 /** Number of arguments */
175 unsigned numargs;
176
177 /** Array of arguments */
178 struct fuse_in_arg args[3];
179 };
180
181 /** One output argument of a request */
182 struct fuse_arg {
183 unsigned size;
184 void *value;
185 };
186
187 /** The request output */
188 struct fuse_out {
189 /** Header returned from userspace */
190 struct fuse_out_header h;
191
192 /*
193 * The following bitfields are not changed during the request
194 * processing
195 */
196
197 /** Last argument is variable length (can be shorter than
198 arg->size) */
199 unsigned argvar:1;
200
201 /** Last argument is a list of pages to copy data to */
202 unsigned argpages:1;
203
204 /** Zero partially or not copied pages */
205 unsigned page_zeroing:1;
206
207 /** Pages may be replaced with new ones */
208 unsigned page_replace:1;
209
210 /** Number or arguments */
211 unsigned numargs;
212
213 /** Array of arguments */
214 struct fuse_arg args[2];
215 };
216
217 /** FUSE page descriptor */
218 struct fuse_page_desc {
219 unsigned int length;
220 unsigned int offset;
221 };
222
223 struct fuse_args {
224 struct {
225 struct {
226 uint32_t opcode;
227 uint64_t nodeid;
228 } h;
229 unsigned numargs;
230 struct fuse_in_arg args[3];
231
232 } in;
233 struct {
234 unsigned argvar:1;
235 unsigned numargs;
236 struct fuse_arg args[2];
237 } out;
238 };
239
240 #define FUSE_ARGS(args) struct fuse_args args = {}
241
242 /** The request IO state (for asynchronous processing) */
243 struct fuse_io_priv {
244 struct kref refcnt;
245 int async;
246 spinlock_t lock;
247 unsigned reqs;
248 ssize_t bytes;
249 size_t size;
250 __u64 offset;
251 bool write;
252 bool should_dirty;
253 int err;
254 struct kiocb *iocb;
255 struct completion *done;
256 bool blocking;
257 };
258
259 #define FUSE_IO_PRIV_SYNC(i) \
260 { \
261 .refcnt = KREF_INIT(1), \
262 .async = 0, \
263 .iocb = i, \
264 }
265
266 /**
267 * Request flags
268 *
269 * FR_ISREPLY: set if the request has reply
270 * FR_FORCE: force sending of the request even if interrupted
271 * FR_BACKGROUND: request is sent in the background
272 * FR_WAITING: request is counted as "waiting"
273 * FR_ABORTED: the request was aborted
274 * FR_INTERRUPTED: the request has been interrupted
275 * FR_LOCKED: data is being copied to/from the request
276 * FR_PENDING: request is not yet in userspace
277 * FR_SENT: request is in userspace, waiting for an answer
278 * FR_FINISHED: request is finished
279 * FR_PRIVATE: request is on private list
280 */
281 enum fuse_req_flag {
282 FR_ISREPLY,
283 FR_FORCE,
284 FR_BACKGROUND,
285 FR_WAITING,
286 FR_ABORTED,
287 FR_INTERRUPTED,
288 FR_LOCKED,
289 FR_PENDING,
290 FR_SENT,
291 FR_FINISHED,
292 FR_PRIVATE,
293 };
294
295 /**
296 * A request to the client
297 *
298 * .waitq.lock protects the following fields:
299 * - FR_ABORTED
300 * - FR_LOCKED (may also be modified under fc->lock, tested under both)
301 */
302 struct fuse_req {
303 /** This can be on either pending processing or io lists in
304 fuse_conn */
305 struct list_head list;
306
307 /** Entry on the interrupts list */
308 struct list_head intr_entry;
309
310 /** refcount */
311 refcount_t count;
312
313 /** Unique ID for the interrupt request */
314 u64 intr_unique;
315
316 /* Request flags, updated with test/set/clear_bit() */
317 unsigned long flags;
318
319 /** The request input */
320 struct fuse_in in;
321
322 /** The request output */
323 struct fuse_out out;
324
325 /** Used to wake up the task waiting for completion of request*/
326 wait_queue_head_t waitq;
327
328 /** Data for asynchronous requests */
329 union {
330 struct {
331 struct fuse_release_in in;
332 struct inode *inode;
333 } release;
334 struct fuse_init_in init_in;
335 struct fuse_init_out init_out;
336 struct cuse_init_in cuse_init_in;
337 struct {
338 struct fuse_read_in in;
339 u64 attr_ver;
340 } read;
341 struct {
342 struct fuse_write_in in;
343 struct fuse_write_out out;
344 struct fuse_req *next;
345 } write;
346 struct fuse_notify_retrieve_in retrieve_in;
347 } misc;
348
349 /** page vector */
350 struct page **pages;
351
352 /** page-descriptor vector */
353 struct fuse_page_desc *page_descs;
354
355 /** size of the 'pages' array */
356 unsigned max_pages;
357
358 /** inline page vector */
359 struct page *inline_pages[FUSE_REQ_INLINE_PAGES];
360
361 /** inline page-descriptor vector */
362 struct fuse_page_desc inline_page_descs[FUSE_REQ_INLINE_PAGES];
363
364 /** number of pages in vector */
365 unsigned num_pages;
366
367 /** File used in the request (or NULL) */
368 struct fuse_file *ff;
369
370 /** Inode used in the request or NULL */
371 struct inode *inode;
372
373 /** Path used for completing d_canonical_path */
374 struct path *canonical_path;
375
376 /** AIO control block */
377 struct fuse_io_priv *io;
378
379 /** Link on fi->writepages */
380 struct list_head writepages_entry;
381
382 /** Request completion callback */
383 void (*end)(struct fuse_conn *, struct fuse_req *);
384
385 /** Request is stolen from fuse_file->reserved_req */
386 struct file *stolen_file;
387 };
388
389 struct fuse_iqueue {
390 /** Connection established */
391 unsigned connected;
392
393 /** Readers of the connection are waiting on this */
394 wait_queue_head_t waitq;
395
396 /** The next unique request id */
397 u64 reqctr;
398
399 /** The list of pending requests */
400 struct list_head pending;
401
402 /** Pending interrupts */
403 struct list_head interrupts;
404
405 /** Queue of pending forgets */
406 struct fuse_forget_link forget_list_head;
407 struct fuse_forget_link *forget_list_tail;
408
409 /** Batching of FORGET requests (positive indicates FORGET batch) */
410 int forget_batch;
411
412 /** O_ASYNC requests */
413 struct fasync_struct *fasync;
414 };
415
416 struct fuse_pqueue {
417 /** Connection established */
418 unsigned connected;
419
420 /** Lock protecting accessess to members of this structure */
421 spinlock_t lock;
422
423 /** The list of requests being processed */
424 struct list_head processing;
425
426 /** The list of requests under I/O */
427 struct list_head io;
428 };
429
430 /**
431 * Fuse device instance
432 */
433 struct fuse_dev {
434 /** Fuse connection for this device */
435 struct fuse_conn *fc;
436
437 /** Processing queue */
438 struct fuse_pqueue pq;
439
440 /** list entry on fc->devices */
441 struct list_head entry;
442 };
443
444 /**
445 * A Fuse connection.
446 *
447 * This structure is created, when the filesystem is mounted, and is
448 * destroyed, when the client device is closed and the filesystem is
449 * unmounted.
450 */
451 struct fuse_conn {
452 /** Lock protecting accessess to members of this structure */
453 spinlock_t lock;
454
455 /** Refcount */
456 refcount_t count;
457
458 /** Number of fuse_dev's */
459 atomic_t dev_count;
460
461 struct rcu_head rcu;
462
463 /** The user id for this mount */
464 kuid_t user_id;
465
466 /** The group id for this mount */
467 kgid_t group_id;
468
469 /** The pid namespace for this mount */
470 struct pid_namespace *pid_ns;
471
472 /** Maximum read size */
473 unsigned max_read;
474
475 /** Maximum write size */
476 unsigned max_write;
477
478 /** Input queue */
479 struct fuse_iqueue iq;
480
481 /** The next unique kernel file handle */
482 u64 khctr;
483
484 /** rbtree of fuse_files waiting for poll events indexed by ph */
485 struct rb_root polled_files;
486
487 /** Maximum number of outstanding background requests */
488 unsigned max_background;
489
490 /** Number of background requests at which congestion starts */
491 unsigned congestion_threshold;
492
493 /** Number of requests currently in the background */
494 unsigned num_background;
495
496 /** Number of background requests currently queued for userspace */
497 unsigned active_background;
498
499 /** The list of background requests set aside for later queuing */
500 struct list_head bg_queue;
501
502 /** Flag indicating that INIT reply has been received. Allocating
503 * any fuse request will be suspended until the flag is set */
504 int initialized;
505
506 /** Flag indicating if connection is blocked. This will be
507 the case before the INIT reply is received, and if there
508 are too many outstading backgrounds requests */
509 int blocked;
510
511 /** waitq for blocked connection */
512 wait_queue_head_t blocked_waitq;
513
514 /** waitq for reserved requests */
515 wait_queue_head_t reserved_req_waitq;
516
517 /** Connection established, cleared on umount, connection
518 abort and device release */
519 unsigned connected;
520
521 /** Connection failed (version mismatch). Cannot race with
522 setting other bitfields since it is only set once in INIT
523 reply, before any other request, and never cleared */
524 unsigned conn_error:1;
525
526 /** Connection successful. Only set in INIT */
527 unsigned conn_init:1;
528
529 /** Do readpages asynchronously? Only set in INIT */
530 unsigned async_read:1;
531
532 /** Do not send separate SETATTR request before open(O_TRUNC) */
533 unsigned atomic_o_trunc:1;
534
535 /** Filesystem supports NFS exporting. Only set in INIT */
536 unsigned export_support:1;
537
538 /** write-back cache policy (default is write-through) */
539 unsigned writeback_cache:1;
540
541 /** allow parallel lookups and readdir (default is serialized) */
542 unsigned parallel_dirops:1;
543
544 /** handle fs handles killing suid/sgid/cap on write/chown/trunc */
545 unsigned handle_killpriv:1;
546
547 /*
548 * The following bitfields are only for optimization purposes
549 * and hence races in setting them will not cause malfunction
550 */
551
552 /** Is open/release not implemented by fs? */
553 unsigned no_open:1;
554
555 /** Is fsync not implemented by fs? */
556 unsigned no_fsync:1;
557
558 /** Is fsyncdir not implemented by fs? */
559 unsigned no_fsyncdir:1;
560
561 /** Is flush not implemented by fs? */
562 unsigned no_flush:1;
563
564 /** Is setxattr not implemented by fs? */
565 unsigned no_setxattr:1;
566
567 /** Is getxattr not implemented by fs? */
568 unsigned no_getxattr:1;
569
570 /** Is listxattr not implemented by fs? */
571 unsigned no_listxattr:1;
572
573 /** Is removexattr not implemented by fs? */
574 unsigned no_removexattr:1;
575
576 /** Are posix file locking primitives not implemented by fs? */
577 unsigned no_lock:1;
578
579 /** Is access not implemented by fs? */
580 unsigned no_access:1;
581
582 /** Is create not implemented by fs? */
583 unsigned no_create:1;
584
585 /** Is interrupt not implemented by fs? */
586 unsigned no_interrupt:1;
587
588 /** Is bmap not implemented by fs? */
589 unsigned no_bmap:1;
590
591 /** Is poll not implemented by fs? */
592 unsigned no_poll:1;
593
594 /** Do multi-page cached writes */
595 unsigned big_writes:1;
596
597 /** Don't apply umask to creation modes */
598 unsigned dont_mask:1;
599
600 /** Are BSD file locking primitives not implemented by fs? */
601 unsigned no_flock:1;
602
603 /** Is fallocate not implemented by fs? */
604 unsigned no_fallocate:1;
605
606 /** Is rename with flags implemented by fs? */
607 unsigned no_rename2:1;
608
609 /** Use enhanced/automatic page cache invalidation. */
610 unsigned auto_inval_data:1;
611
612 /** Does the filesystem support readdirplus? */
613 unsigned do_readdirplus:1;
614
615 /** Does the filesystem want adaptive readdirplus? */
616 unsigned readdirplus_auto:1;
617
618 /** Does the filesystem support asynchronous direct-IO submission? */
619 unsigned async_dio:1;
620
621 /** Is lseek not implemented by fs? */
622 unsigned no_lseek:1;
623
624 /** Does the filesystem support posix acls? */
625 unsigned posix_acl:1;
626
627 /** Check permissions based on the file mode or not? */
628 unsigned default_permissions:1;
629
630 /** Allow other than the mounter user to access the filesystem ? */
631 unsigned allow_other:1;
632
633 /** The number of requests waiting for completion */
634 atomic_t num_waiting;
635
636 /** Negotiated minor version */
637 unsigned minor;
638
639 /** Entry on the fuse_conn_list */
640 struct list_head entry;
641
642 /** Device ID from super block */
643 dev_t dev;
644
645 /** Dentries in the control filesystem */
646 struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
647
648 /** number of dentries used in the above array */
649 int ctl_ndents;
650
651 /** Key for lock owner ID scrambling */
652 u32 scramble_key[4];
653
654 /** Reserved request for the DESTROY message */
655 struct fuse_req *destroy_req;
656
657 /** Version counter for attribute changes */
658 u64 attr_version;
659
660 /** Called on final put */
661 void (*release)(struct fuse_conn *);
662
663 /** Super block for this connection. */
664 struct super_block *sb;
665
666 /** Read/write semaphore to hold when accessing sb. */
667 struct rw_semaphore killsb;
668
669 /** List of device instances belonging to this connection */
670 struct list_head devices;
671 };
672
get_fuse_conn_super(struct super_block * sb)673 static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
674 {
675 return sb->s_fs_info;
676 }
677
get_fuse_conn(struct inode * inode)678 static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
679 {
680 return get_fuse_conn_super(inode->i_sb);
681 }
682
get_fuse_inode(struct inode * inode)683 static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
684 {
685 return container_of(inode, struct fuse_inode, inode);
686 }
687
get_node_id(struct inode * inode)688 static inline u64 get_node_id(struct inode *inode)
689 {
690 return get_fuse_inode(inode)->nodeid;
691 }
692
693 /** Device operations */
694 extern const struct file_operations fuse_dev_operations;
695
696 extern const struct dentry_operations fuse_dentry_operations;
697 extern const struct dentry_operations fuse_root_dentry_operations;
698
699 /**
700 * Inode to nodeid comparison.
701 */
702 int fuse_inode_eq(struct inode *inode, void *_nodeidp);
703
704 /**
705 * Get a filled in inode
706 */
707 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
708 int generation, struct fuse_attr *attr,
709 u64 attr_valid, u64 attr_version);
710
711 int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name,
712 struct fuse_entry_out *outarg, struct inode **inode);
713
714 /**
715 * Send FORGET command
716 */
717 void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
718 u64 nodeid, u64 nlookup);
719
720 struct fuse_forget_link *fuse_alloc_forget(void);
721
722 /* Used by READDIRPLUS */
723 void fuse_force_forget(struct file *file, u64 nodeid);
724
725 /**
726 * Initialize READ or READDIR request
727 */
728 void fuse_read_fill(struct fuse_req *req, struct file *file,
729 loff_t pos, size_t count, int opcode);
730
731 /**
732 * Send OPEN or OPENDIR request
733 */
734 int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
735
736 struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
737 void fuse_file_free(struct fuse_file *ff);
738 void fuse_finish_open(struct inode *inode, struct file *file);
739
740 void fuse_sync_release(struct fuse_file *ff, int flags);
741
742 /**
743 * Send RELEASE or RELEASEDIR request
744 */
745 void fuse_release_common(struct file *file, bool isdir);
746
747 /**
748 * Send FSYNC or FSYNCDIR request
749 */
750 int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
751 int datasync, int isdir);
752
753 /**
754 * Notify poll wakeup
755 */
756 int fuse_notify_poll_wakeup(struct fuse_conn *fc,
757 struct fuse_notify_poll_wakeup_out *outarg);
758
759 /**
760 * Initialize file operations on a regular file
761 */
762 void fuse_init_file_inode(struct inode *inode);
763
764 /**
765 * Initialize inode operations on regular files and special files
766 */
767 void fuse_init_common(struct inode *inode);
768
769 /**
770 * Initialize inode and file operations on a directory
771 */
772 void fuse_init_dir(struct inode *inode);
773
774 /**
775 * Initialize inode operations on a symlink
776 */
777 void fuse_init_symlink(struct inode *inode);
778
779 /**
780 * Change attributes of an inode
781 */
782 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
783 u64 attr_valid, u64 attr_version);
784
785 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
786 u64 attr_valid);
787
788 /**
789 * Initialize the client device
790 */
791 int fuse_dev_init(void);
792
793 /**
794 * Cleanup the client device
795 */
796 void fuse_dev_cleanup(void);
797
798 int fuse_ctl_init(void);
799 void __exit fuse_ctl_cleanup(void);
800
801 /**
802 * Allocate a request
803 */
804 struct fuse_req *fuse_request_alloc(unsigned npages);
805
806 struct fuse_req *fuse_request_alloc_nofs(unsigned npages);
807
808 /**
809 * Free a request
810 */
811 void fuse_request_free(struct fuse_req *req);
812
813 /**
814 * Get a request, may fail with -ENOMEM,
815 * caller should specify # elements in req->pages[] explicitly
816 */
817 struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages);
818 struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
819 unsigned npages);
820
821 /*
822 * Increment reference count on request
823 */
824 void __fuse_get_request(struct fuse_req *req);
825
826 /**
827 * Gets a requests for a file operation, always succeeds
828 */
829 struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
830 struct file *file);
831
832 /**
833 * Decrement reference count of a request. If count goes to zero free
834 * the request.
835 */
836 void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
837
838 /**
839 * Send a request (synchronous)
840 */
841 void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);
842
843 /**
844 * Simple request sending that does request allocation and freeing
845 */
846 ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args);
847
848 /**
849 * Send a request in the background
850 */
851 void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req);
852
853 void fuse_request_send_background_locked(struct fuse_conn *fc,
854 struct fuse_req *req);
855
856 /* Abort all requests */
857 void fuse_abort_conn(struct fuse_conn *fc);
858 void fuse_wait_aborted(struct fuse_conn *fc);
859
860 /**
861 * Invalidate inode attributes
862 */
863 void fuse_invalidate_attr(struct inode *inode);
864
865 void fuse_invalidate_entry_cache(struct dentry *entry);
866
867 void fuse_invalidate_atime(struct inode *inode);
868
869 /**
870 * Acquire reference to fuse_conn
871 */
872 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
873
874 /**
875 * Initialize fuse_conn
876 */
877 void fuse_conn_init(struct fuse_conn *fc);
878
879 /**
880 * Release reference to fuse_conn
881 */
882 void fuse_conn_put(struct fuse_conn *fc);
883
884 struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc);
885 void fuse_dev_free(struct fuse_dev *fud);
886
887 /**
888 * Add connection to control filesystem
889 */
890 int fuse_ctl_add_conn(struct fuse_conn *fc);
891
892 /**
893 * Remove connection from control filesystem
894 */
895 void fuse_ctl_remove_conn(struct fuse_conn *fc);
896
897 /**
898 * Is file type valid?
899 */
900 int fuse_valid_type(int m);
901
902 bool fuse_invalid_attr(struct fuse_attr *attr);
903
904 /**
905 * Is current process allowed to perform filesystem operation?
906 */
907 int fuse_allow_current_process(struct fuse_conn *fc);
908
909 u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
910
911 void fuse_update_ctime(struct inode *inode);
912
913 int fuse_update_attributes(struct inode *inode, struct file *file);
914
915 void fuse_flush_writepages(struct inode *inode);
916
917 void fuse_set_nowrite(struct inode *inode);
918 void fuse_release_nowrite(struct inode *inode);
919
920 u64 fuse_get_attr_version(struct fuse_conn *fc);
921
922 /**
923 * File-system tells the kernel to invalidate cache for the given node id.
924 */
925 int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
926 loff_t offset, loff_t len);
927
928 /**
929 * File-system tells the kernel to invalidate parent attributes and
930 * the dentry matching parent/name.
931 *
932 * If the child_nodeid is non-zero and:
933 * - matches the inode number for the dentry matching parent/name,
934 * - is not a mount point
935 * - is a file or oan empty directory
936 * then the dentry is unhashed (d_delete()).
937 */
938 int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
939 u64 child_nodeid, struct qstr *name);
940
941 int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
942 bool isdir);
943
944 /**
945 * fuse_direct_io() flags
946 */
947
948 /** If set, it is WRITE; otherwise - READ */
949 #define FUSE_DIO_WRITE (1 << 0)
950
951 /** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */
952 #define FUSE_DIO_CUSE (1 << 1)
953
954 ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
955 loff_t *ppos, int flags);
956 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
957 unsigned int flags);
958 long fuse_ioctl_common(struct file *file, unsigned int cmd,
959 unsigned long arg, unsigned int flags);
960 unsigned fuse_file_poll(struct file *file, poll_table *wait);
961 int fuse_dev_release(struct inode *inode, struct file *file);
962
963 bool fuse_write_update_size(struct inode *inode, loff_t pos);
964
965 int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
966 int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
967
968 int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
969 struct file *file);
970
971 void fuse_set_initialized(struct fuse_conn *fc);
972
973 void fuse_unlock_inode(struct inode *inode, bool locked);
974 bool fuse_lock_inode(struct inode *inode);
975
976 int fuse_setxattr(struct inode *inode, const char *name, const void *value,
977 size_t size, int flags);
978 ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
979 size_t size);
980 ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
981 int fuse_removexattr(struct inode *inode, const char *name);
982 extern const struct xattr_handler *fuse_xattr_handlers[];
983 extern const struct xattr_handler *fuse_acl_xattr_handlers[];
984
985 struct posix_acl;
986 struct posix_acl *fuse_get_acl(struct inode *inode, int type);
987 int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
988
989 #endif /* _FS_FUSE_I_H */
990