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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
26/** Max number of pages that can be used in a single read request */
27#define FUSE_MAX_PAGES_PER_REQ 32
28
29/** Bias for fi->writectr, meaning new writepages must not be sent */
30#define FUSE_NOWRITE INT_MIN
31
32/** It could be as large as PATH_MAX, but would that have any uses? */
33#define FUSE_NAME_MAX 1024
34
35/** Number of dentries for each connection in the control filesystem */
36#define FUSE_CTL_NUM_DENTRIES 5
37
38/** If the FUSE_DEFAULT_PERMISSIONS flag is given, the filesystem
39 module will check permissions based on the file mode. Otherwise no
40 permission checking is done in the kernel */
41#define FUSE_DEFAULT_PERMISSIONS (1 << 0)
42
43/** If the FUSE_ALLOW_OTHER flag is given, then not only the user
44 doing the mount will be allowed to access the filesystem */
45#define FUSE_ALLOW_OTHER (1 << 1)
46
47/** List of active connections */
48extern struct list_head fuse_conn_list;
49
50/** Global mutex protecting fuse_conn_list and the control filesystem */
51extern struct mutex fuse_mutex;
52
53/** Module parameters */
54extern unsigned max_user_bgreq;
55extern unsigned max_user_congthresh;
56
57/* One forget request */
58struct fuse_forget_link {
59 struct fuse_forget_one forget_one;
60 struct fuse_forget_link *next;
61};
62
63/** FUSE inode */
64struct fuse_inode {
65 /** Inode data */
66 struct inode inode;
67
68 /** Unique ID, which identifies the inode between userspace
69 * and kernel */
70 u64 nodeid;
71
72 /** Number of lookups on this inode */
73 u64 nlookup;
74
75 /** The request used for sending the FORGET message */
76 struct fuse_forget_link *forget;
77
78 /** Time in jiffies until the file attributes are valid */
79 u64 i_time;
80
81 /** The sticky bit in inode->i_mode may have been removed, so
82 preserve the original mode */
83 mode_t orig_i_mode;
84
85 /** Version of last attribute change */
86 u64 attr_version;
87
88 /** Files usable in writepage. Protected by fc->lock */
89 struct list_head write_files;
90
91 /** Writepages pending on truncate or fsync */
92 struct list_head queued_writes;
93
94 /** Number of sent writes, a negative bias (FUSE_NOWRITE)
95 * means more writes are blocked */
96 int writectr;
97
98 /** Waitq for writepage completion */
99 wait_queue_head_t page_waitq;
100
101 /** List of writepage requestst (pending or sent) */
102 struct list_head writepages;
103};
104
105struct fuse_conn;
106
107/** FUSE specific file data */
108struct fuse_file {
109 /** Fuse connection for this file */
110 struct fuse_conn *fc;
111
112 /** Request reserved for flush and release */
113 struct fuse_req *reserved_req;
114
115 /** Kernel file handle guaranteed to be unique */
116 u64 kh;
117
118 /** File handle used by userspace */
119 u64 fh;
120
121 /** Node id of this file */
122 u64 nodeid;
123
124 /** Refcount */
125 atomic_t count;
126
127 /** FOPEN_* flags returned by open */
128 u32 open_flags;
129
130 /** Entry on inode's write_files list */
131 struct list_head write_entry;
132
133 /** RB node to be linked on fuse_conn->polled_files */
134 struct rb_node polled_node;
135
136 /** Wait queue head for poll */
137 wait_queue_head_t poll_wait;
138
139 /** Has flock been performed on this file? */
140 bool flock:1;
141};
142
143/** One input argument of a request */
144struct fuse_in_arg {
145 unsigned size;
146 const void *value;
147};
148
149/** The request input */
150struct fuse_in {
151 /** The request header */
152 struct fuse_in_header h;
153
154 /** True if the data for the last argument is in req->pages */
155 unsigned argpages:1;
156
157 /** Number of arguments */
158 unsigned numargs;
159
160 /** Array of arguments */
161 struct fuse_in_arg args[3];
162};
163
164/** One output argument of a request */
165struct fuse_arg {
166 unsigned size;
167 void *value;
168};
169
170/** The request output */
171struct fuse_out {
172 /** Header returned from userspace */
173 struct fuse_out_header h;
174
175 /*
176 * The following bitfields are not changed during the request
177 * processing
178 */
179
180 /** Last argument is variable length (can be shorter than
181 arg->size) */
182 unsigned argvar:1;
183
184 /** Last argument is a list of pages to copy data to */
185 unsigned argpages:1;
186
187 /** Zero partially or not copied pages */
188 unsigned page_zeroing:1;
189
190 /** Pages may be replaced with new ones */
191 unsigned page_replace:1;
192
193 /** Number or arguments */
194 unsigned numargs;
195
196 /** Array of arguments */
197 struct fuse_arg args[3];
198};
199
200/** The request state */
201enum fuse_req_state {
202 FUSE_REQ_INIT = 0,
203 FUSE_REQ_PENDING,
204 FUSE_REQ_READING,
205 FUSE_REQ_SENT,
206 FUSE_REQ_WRITING,
207 FUSE_REQ_FINISHED
208};
209
210/**
211 * A request to the client
212 */
213struct fuse_req {
214 /** This can be on either pending processing or io lists in
215 fuse_conn */
216 struct list_head list;
217
218 /** Entry on the interrupts list */
219 struct list_head intr_entry;
220
221 /** refcount */
222 atomic_t count;
223
224 /** Unique ID for the interrupt request */
225 u64 intr_unique;
226
227 /*
228 * The following bitfields are either set once before the
229 * request is queued or setting/clearing them is protected by
230 * fuse_conn->lock
231 */
232
233 /** True if the request has reply */
234 unsigned isreply:1;
235
236 /** Force sending of the request even if interrupted */
237 unsigned force:1;
238
239 /** The request was aborted */
240 unsigned aborted:1;
241
242 /** Request is sent in the background */
243 unsigned background:1;
244
245 /** The request has been interrupted */
246 unsigned interrupted:1;
247
248 /** Data is being copied to/from the request */
249 unsigned locked:1;
250
251 /** Request is counted as "waiting" */
252 unsigned waiting:1;
253
254 /** State of the request */
255 enum fuse_req_state state;
256
257 /** The request input */
258 struct fuse_in in;
259
260 /** The request output */
261 struct fuse_out out;
262
263 /** Used to wake up the task waiting for completion of request*/
264 wait_queue_head_t waitq;
265
266 /** Data for asynchronous requests */
267 union {
268 struct {
269 union {
270 struct fuse_release_in in;
271 struct work_struct work;
272 };
273 struct path path;
274 } release;
275 struct fuse_init_in init_in;
276 struct fuse_init_out init_out;
277 struct cuse_init_in cuse_init_in;
278 struct {
279 struct fuse_read_in in;
280 u64 attr_ver;
281 } read;
282 struct {
283 struct fuse_write_in in;
284 struct fuse_write_out out;
285 } write;
286 struct fuse_notify_retrieve_in retrieve_in;
287 struct fuse_lk_in lk_in;
288 } misc;
289
290 /** page vector */
291 struct page *pages[FUSE_MAX_PAGES_PER_REQ];
292
293 /** number of pages in vector */
294 unsigned num_pages;
295
296 /** offset of data on first page */
297 unsigned page_offset;
298
299 /** File used in the request (or NULL) */
300 struct fuse_file *ff;
301
302 /** Inode used in the request or NULL */
303 struct inode *inode;
304
305 /** Link on fi->writepages */
306 struct list_head writepages_entry;
307
308 /** Request completion callback */
309 void (*end)(struct fuse_conn *, struct fuse_req *);
310
311 /** Request is stolen from fuse_file->reserved_req */
312 struct file *stolen_file;
313};
314
315/**
316 * A Fuse connection.
317 *
318 * This structure is created, when the filesystem is mounted, and is
319 * destroyed, when the client device is closed and the filesystem is
320 * unmounted.
321 */
322struct fuse_conn {
323 /** Lock protecting accessess to members of this structure */
324 spinlock_t lock;
325
326 /** Mutex protecting against directory alias creation */
327 struct mutex inst_mutex;
328
329 /** Refcount */
330 atomic_t count;
331
332 /** The user id for this mount */
333 uid_t user_id;
334
335 /** The group id for this mount */
336 gid_t group_id;
337
338 /** The fuse mount flags for this mount */
339 unsigned flags;
340
341 /** Maximum read size */
342 unsigned max_read;
343
344 /** Maximum write size */
345 unsigned max_write;
346
347 /** Readers of the connection are waiting on this */
348 wait_queue_head_t waitq;
349
350 /** The list of pending requests */
351 struct list_head pending;
352
353 /** The list of requests being processed */
354 struct list_head processing;
355
356 /** The list of requests under I/O */
357 struct list_head io;
358
359 /** The next unique kernel file handle */
360 u64 khctr;
361
362 /** rbtree of fuse_files waiting for poll events indexed by ph */
363 struct rb_root polled_files;
364
365 /** Maximum number of outstanding background requests */
366 unsigned max_background;
367
368 /** Number of background requests at which congestion starts */
369 unsigned congestion_threshold;
370
371 /** Number of requests currently in the background */
372 unsigned num_background;
373
374 /** Number of background requests currently queued for userspace */
375 unsigned active_background;
376
377 /** The list of background requests set aside for later queuing */
378 struct list_head bg_queue;
379
380 /** Pending interrupts */
381 struct list_head interrupts;
382
383 /** Queue of pending forgets */
384 struct fuse_forget_link forget_list_head;
385 struct fuse_forget_link *forget_list_tail;
386
387 /** Batching of FORGET requests (positive indicates FORGET batch) */
388 int forget_batch;
389
390 /** Flag indicating if connection is blocked. This will be
391 the case before the INIT reply is received, and if there
392 are too many outstading backgrounds requests */
393 int blocked;
394
395 /** waitq for blocked connection */
396 wait_queue_head_t blocked_waitq;
397
398 /** waitq for reserved requests */
399 wait_queue_head_t reserved_req_waitq;
400
401 /** The next unique request id */
402 u64 reqctr;
403
404 /** Connection established, cleared on umount, connection
405 abort and device release */
406 unsigned connected;
407
408 /** Connection failed (version mismatch). Cannot race with
409 setting other bitfields since it is only set once in INIT
410 reply, before any other request, and never cleared */
411 unsigned conn_error:1;
412
413 /** Connection successful. Only set in INIT */
414 unsigned conn_init:1;
415
416 /** Do readpages asynchronously? Only set in INIT */
417 unsigned async_read:1;
418
419 /** Do not send separate SETATTR request before open(O_TRUNC) */
420 unsigned atomic_o_trunc:1;
421
422 /** Filesystem supports NFS exporting. Only set in INIT */
423 unsigned export_support:1;
424
425 /** Set if bdi is valid */
426 unsigned bdi_initialized:1;
427
428 /*
429 * The following bitfields are only for optimization purposes
430 * and hence races in setting them will not cause malfunction
431 */
432
433 /** Is fsync not implemented by fs? */
434 unsigned no_fsync:1;
435
436 /** Is fsyncdir not implemented by fs? */
437 unsigned no_fsyncdir:1;
438
439 /** Is flush not implemented by fs? */
440 unsigned no_flush:1;
441
442 /** Is setxattr not implemented by fs? */
443 unsigned no_setxattr:1;
444
445 /** Is getxattr not implemented by fs? */
446 unsigned no_getxattr:1;
447
448 /** Is listxattr not implemented by fs? */
449 unsigned no_listxattr:1;
450
451 /** Is removexattr not implemented by fs? */
452 unsigned no_removexattr:1;
453
454 /** Are posix file locking primitives not implemented by fs? */
455 unsigned no_lock:1;
456
457 /** Is access not implemented by fs? */
458 unsigned no_access:1;
459
460 /** Is create not implemented by fs? */
461 unsigned no_create:1;
462
463 /** Is interrupt not implemented by fs? */
464 unsigned no_interrupt:1;
465
466 /** Is bmap not implemented by fs? */
467 unsigned no_bmap:1;
468
469 /** Is poll not implemented by fs? */
470 unsigned no_poll:1;
471
472 /** Do multi-page cached writes */
473 unsigned big_writes:1;
474
475 /** Don't apply umask to creation modes */
476 unsigned dont_mask:1;
477
478 /** Are BSD file locking primitives not implemented by fs? */
479 unsigned no_flock:1;
480
481 /** The number of requests waiting for completion */
482 atomic_t num_waiting;
483
484 /** Negotiated minor version */
485 unsigned minor;
486
487 /** Backing dev info */
488 struct backing_dev_info bdi;
489
490 /** Entry on the fuse_conn_list */
491 struct list_head entry;
492
493 /** Device ID from super block */
494 dev_t dev;
495
496 /** Dentries in the control filesystem */
497 struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
498
499 /** number of dentries used in the above array */
500 int ctl_ndents;
501
502 /** O_ASYNC requests */
503 struct fasync_struct *fasync;
504
505 /** Key for lock owner ID scrambling */
506 u32 scramble_key[4];
507
508 /** Reserved request for the DESTROY message */
509 struct fuse_req *destroy_req;
510
511 /** Version counter for attribute changes */
512 u64 attr_version;
513
514 /** Called on final put */
515 void (*release)(struct fuse_conn *);
516
517 /** Super block for this connection. */
518 struct super_block *sb;
519
520 /** Read/write semaphore to hold when accessing sb. */
521 struct rw_semaphore killsb;
522};
523
524static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
525{
526 return sb->s_fs_info;
527}
528
529static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
530{
531 return get_fuse_conn_super(inode->i_sb);
532}
533
534static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
535{
536 return container_of(inode, struct fuse_inode, inode);
537}
538
539static inline u64 get_node_id(struct inode *inode)
540{
541 return get_fuse_inode(inode)->nodeid;
542}
543
544/** Device operations */
545extern const struct file_operations fuse_dev_operations;
546
547extern const struct dentry_operations fuse_dentry_operations;
548
549/**
550 * Inode to nodeid comparison.
551 */
552int fuse_inode_eq(struct inode *inode, void *_nodeidp);
553
554/**
555 * Get a filled in inode
556 */
557struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
558 int generation, struct fuse_attr *attr,
559 u64 attr_valid, u64 attr_version);
560
561int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
562 struct fuse_entry_out *outarg, struct inode **inode);
563
564/**
565 * Send FORGET command
566 */
567void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
568 u64 nodeid, u64 nlookup);
569
570struct fuse_forget_link *fuse_alloc_forget(void);
571
572/**
573 * Initialize READ or READDIR request
574 */
575void fuse_read_fill(struct fuse_req *req, struct file *file,
576 loff_t pos, size_t count, int opcode);
577
578/**
579 * Send OPEN or OPENDIR request
580 */
581int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
582
583struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
584struct fuse_file *fuse_file_get(struct fuse_file *ff);
585void fuse_file_free(struct fuse_file *ff);
586void fuse_finish_open(struct inode *inode, struct file *file);
587
588void fuse_sync_release(struct fuse_file *ff, int flags);
589
590/**
591 * Send RELEASE or RELEASEDIR request
592 */
593void fuse_release_common(struct file *file, int opcode);
594
595/**
596 * Send FSYNC or FSYNCDIR request
597 */
598int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
599 int datasync, int isdir);
600
601/**
602 * Notify poll wakeup
603 */
604int fuse_notify_poll_wakeup(struct fuse_conn *fc,
605 struct fuse_notify_poll_wakeup_out *outarg);
606
607/**
608 * Initialize file operations on a regular file
609 */
610void fuse_init_file_inode(struct inode *inode);
611
612/**
613 * Initialize inode operations on regular files and special files
614 */
615void fuse_init_common(struct inode *inode);
616
617/**
618 * Initialize inode and file operations on a directory
619 */
620void fuse_init_dir(struct inode *inode);
621
622/**
623 * Initialize inode operations on a symlink
624 */
625void fuse_init_symlink(struct inode *inode);
626
627/**
628 * Change attributes of an inode
629 */
630void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
631 u64 attr_valid, u64 attr_version);
632
633void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
634 u64 attr_valid);
635
636/**
637 * Initialize the client device
638 */
639int fuse_dev_init(void);
640
641/**
642 * Cleanup the client device
643 */
644void fuse_dev_cleanup(void);
645
646int fuse_ctl_init(void);
647void fuse_ctl_cleanup(void);
648
649/**
650 * Allocate a request
651 */
652struct fuse_req *fuse_request_alloc(void);
653
654struct fuse_req *fuse_request_alloc_nofs(void);
655
656/**
657 * Free a request
658 */
659void fuse_request_free(struct fuse_req *req);
660
661/**
662 * Get a request, may fail with -ENOMEM
663 */
664struct fuse_req *fuse_get_req(struct fuse_conn *fc);
665
666/**
667 * Gets a requests for a file operation, always succeeds
668 */
669struct fuse_req *fuse_get_req_nofail(struct fuse_conn *fc, struct file *file);
670
671/**
672 * Decrement reference count of a request. If count goes to zero free
673 * the request.
674 */
675void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
676
677/**
678 * Send a request (synchronous)
679 */
680void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);
681
682/**
683 * Send a request in the background
684 */
685void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req);
686
687void fuse_request_send_background_locked(struct fuse_conn *fc,
688 struct fuse_req *req);
689
690/* Abort all requests */
691void fuse_abort_conn(struct fuse_conn *fc);
692
693/**
694 * Invalidate inode attributes
695 */
696void fuse_invalidate_attr(struct inode *inode);
697
698void fuse_invalidate_entry_cache(struct dentry *entry);
699
700/**
701 * Acquire reference to fuse_conn
702 */
703struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
704
705void fuse_conn_kill(struct fuse_conn *fc);
706
707/**
708 * Initialize fuse_conn
709 */
710void fuse_conn_init(struct fuse_conn *fc);
711
712/**
713 * Release reference to fuse_conn
714 */
715void fuse_conn_put(struct fuse_conn *fc);
716
717/**
718 * Add connection to control filesystem
719 */
720int fuse_ctl_add_conn(struct fuse_conn *fc);
721
722/**
723 * Remove connection from control filesystem
724 */
725void fuse_ctl_remove_conn(struct fuse_conn *fc);
726
727/**
728 * Is file type valid?
729 */
730int fuse_valid_type(int m);
731
732/**
733 * Is task allowed to perform filesystem operation?
734 */
735int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task);
736
737u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
738
739int fuse_update_attributes(struct inode *inode, struct kstat *stat,
740 struct file *file, bool *refreshed);
741
742void fuse_flush_writepages(struct inode *inode);
743
744void fuse_set_nowrite(struct inode *inode);
745void fuse_release_nowrite(struct inode *inode);
746
747u64 fuse_get_attr_version(struct fuse_conn *fc);
748
749/**
750 * File-system tells the kernel to invalidate cache for the given node id.
751 */
752int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
753 loff_t offset, loff_t len);
754
755/**
756 * File-system tells the kernel to invalidate parent attributes and
757 * the dentry matching parent/name.
758 */
759int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
760 struct qstr *name);
761
762int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
763 bool isdir);
764ssize_t fuse_direct_io(struct file *file, const char __user *buf,
765 size_t count, loff_t *ppos, int write);
766long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
767 unsigned int flags);
768unsigned fuse_file_poll(struct file *file, poll_table *wait);
769int fuse_dev_release(struct inode *inode, struct file *file);
770
771void fuse_write_update_size(struct inode *inode, loff_t pos);
772
773#endif /* _FS_FUSE_I_H */
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#ifndef pr_fmt
13# define pr_fmt(fmt) "fuse: " fmt
14#endif
15
16#include <linux/fuse.h>
17#include <linux/fs.h>
18#include <linux/mount.h>
19#include <linux/wait.h>
20#include <linux/list.h>
21#include <linux/spinlock.h>
22#include <linux/mm.h>
23#include <linux/backing-dev.h>
24#include <linux/mutex.h>
25#include <linux/rwsem.h>
26#include <linux/rbtree.h>
27#include <linux/poll.h>
28#include <linux/workqueue.h>
29#include <linux/kref.h>
30#include <linux/xattr.h>
31#include <linux/pid_namespace.h>
32#include <linux/refcount.h>
33#include <linux/user_namespace.h>
34
35/** Default max number of pages that can be used in a single read request */
36#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32
37
38/** Maximum of max_pages received in init_out */
39#define FUSE_MAX_MAX_PAGES 256
40
41/** Bias for fi->writectr, meaning new writepages must not be sent */
42#define FUSE_NOWRITE INT_MIN
43
44/** It could be as large as PATH_MAX, but would that have any uses? */
45#define FUSE_NAME_MAX 1024
46
47/** Number of dentries for each connection in the control filesystem */
48#define FUSE_CTL_NUM_DENTRIES 5
49
50/** List of active connections */
51extern struct list_head fuse_conn_list;
52
53/** Global mutex protecting fuse_conn_list and the control filesystem */
54extern struct mutex fuse_mutex;
55
56/** Module parameters */
57extern unsigned max_user_bgreq;
58extern unsigned max_user_congthresh;
59
60/* One forget request */
61struct fuse_forget_link {
62 struct fuse_forget_one forget_one;
63 struct fuse_forget_link *next;
64};
65
66/** FUSE inode */
67struct fuse_inode {
68 /** Inode data */
69 struct inode inode;
70
71 /** Unique ID, which identifies the inode between userspace
72 * and kernel */
73 u64 nodeid;
74
75 /** Number of lookups on this inode */
76 u64 nlookup;
77
78 /** The request used for sending the FORGET message */
79 struct fuse_forget_link *forget;
80
81 /** Time in jiffies until the file attributes are valid */
82 u64 i_time;
83
84 /* Which attributes are invalid */
85 u32 inval_mask;
86
87 /** The sticky bit in inode->i_mode may have been removed, so
88 preserve the original mode */
89 umode_t orig_i_mode;
90
91 /** 64 bit inode number */
92 u64 orig_ino;
93
94 /** Version of last attribute change */
95 u64 attr_version;
96
97 union {
98 /* Write related fields (regular file only) */
99 struct {
100 /* Files usable in writepage. Protected by fi->lock */
101 struct list_head write_files;
102
103 /* Writepages pending on truncate or fsync */
104 struct list_head queued_writes;
105
106 /* Number of sent writes, a negative bias
107 * (FUSE_NOWRITE) means more writes are blocked */
108 int writectr;
109
110 /* Waitq for writepage completion */
111 wait_queue_head_t page_waitq;
112
113 /* List of writepage requestst (pending or sent) */
114 struct list_head writepages;
115 };
116
117 /* readdir cache (directory only) */
118 struct {
119 /* true if fully cached */
120 bool cached;
121
122 /* size of cache */
123 loff_t size;
124
125 /* position at end of cache (position of next entry) */
126 loff_t pos;
127
128 /* version of the cache */
129 u64 version;
130
131 /* modification time of directory when cache was
132 * started */
133 struct timespec64 mtime;
134
135 /* iversion of directory when cache was started */
136 u64 iversion;
137
138 /* protects above fields */
139 spinlock_t lock;
140 } rdc;
141 };
142
143 /** Miscellaneous bits describing inode state */
144 unsigned long state;
145
146 /** Lock for serializing lookup and readdir for back compatibility*/
147 struct mutex mutex;
148
149 /** Lock to protect write related fields */
150 spinlock_t lock;
151};
152
153/** FUSE inode state bits */
154enum {
155 /** Advise readdirplus */
156 FUSE_I_ADVISE_RDPLUS,
157 /** Initialized with readdirplus */
158 FUSE_I_INIT_RDPLUS,
159 /** An operation changing file size is in progress */
160 FUSE_I_SIZE_UNSTABLE,
161};
162
163struct fuse_conn;
164struct fuse_release_args;
165
166/** FUSE specific file data */
167struct fuse_file {
168 /** Fuse connection for this file */
169 struct fuse_conn *fc;
170
171 /* Argument space reserved for release */
172 struct fuse_release_args *release_args;
173
174 /** Kernel file handle guaranteed to be unique */
175 u64 kh;
176
177 /** File handle used by userspace */
178 u64 fh;
179
180 /** Node id of this file */
181 u64 nodeid;
182
183 /** Refcount */
184 refcount_t count;
185
186 /** FOPEN_* flags returned by open */
187 u32 open_flags;
188
189 /** Entry on inode's write_files list */
190 struct list_head write_entry;
191
192 /* Readdir related */
193 struct {
194 /*
195 * Protects below fields against (crazy) parallel readdir on
196 * same open file. Uncontended in the normal case.
197 */
198 struct mutex lock;
199
200 /* Dir stream position */
201 loff_t pos;
202
203 /* Offset in cache */
204 loff_t cache_off;
205
206 /* Version of cache we are reading */
207 u64 version;
208
209 } readdir;
210
211 /** RB node to be linked on fuse_conn->polled_files */
212 struct rb_node polled_node;
213
214 /** Wait queue head for poll */
215 wait_queue_head_t poll_wait;
216
217 /** Has flock been performed on this file? */
218 bool flock:1;
219};
220
221/** One input argument of a request */
222struct fuse_in_arg {
223 unsigned size;
224 const void *value;
225};
226
227/** One output argument of a request */
228struct fuse_arg {
229 unsigned size;
230 void *value;
231};
232
233/** FUSE page descriptor */
234struct fuse_page_desc {
235 unsigned int length;
236 unsigned int offset;
237};
238
239struct fuse_args {
240 uint64_t nodeid;
241 uint32_t opcode;
242 unsigned short in_numargs;
243 unsigned short out_numargs;
244 bool force:1;
245 bool noreply:1;
246 bool nocreds:1;
247 bool in_pages:1;
248 bool out_pages:1;
249 bool out_argvar:1;
250 bool page_zeroing:1;
251 bool page_replace:1;
252 struct fuse_in_arg in_args[3];
253 struct fuse_arg out_args[2];
254 void (*end)(struct fuse_conn *fc, struct fuse_args *args, int error);
255};
256
257struct fuse_args_pages {
258 struct fuse_args args;
259 struct page **pages;
260 struct fuse_page_desc *descs;
261 unsigned int num_pages;
262};
263
264#define FUSE_ARGS(args) struct fuse_args args = {}
265
266/** The request IO state (for asynchronous processing) */
267struct fuse_io_priv {
268 struct kref refcnt;
269 int async;
270 spinlock_t lock;
271 unsigned reqs;
272 ssize_t bytes;
273 size_t size;
274 __u64 offset;
275 bool write;
276 bool should_dirty;
277 int err;
278 struct kiocb *iocb;
279 struct completion *done;
280 bool blocking;
281};
282
283#define FUSE_IO_PRIV_SYNC(i) \
284{ \
285 .refcnt = KREF_INIT(1), \
286 .async = 0, \
287 .iocb = i, \
288}
289
290/**
291 * Request flags
292 *
293 * FR_ISREPLY: set if the request has reply
294 * FR_FORCE: force sending of the request even if interrupted
295 * FR_BACKGROUND: request is sent in the background
296 * FR_WAITING: request is counted as "waiting"
297 * FR_ABORTED: the request was aborted
298 * FR_INTERRUPTED: the request has been interrupted
299 * FR_LOCKED: data is being copied to/from the request
300 * FR_PENDING: request is not yet in userspace
301 * FR_SENT: request is in userspace, waiting for an answer
302 * FR_FINISHED: request is finished
303 * FR_PRIVATE: request is on private list
304 */
305enum fuse_req_flag {
306 FR_ISREPLY,
307 FR_FORCE,
308 FR_BACKGROUND,
309 FR_WAITING,
310 FR_ABORTED,
311 FR_INTERRUPTED,
312 FR_LOCKED,
313 FR_PENDING,
314 FR_SENT,
315 FR_FINISHED,
316 FR_PRIVATE,
317};
318
319/**
320 * A request to the client
321 *
322 * .waitq.lock protects the following fields:
323 * - FR_ABORTED
324 * - FR_LOCKED (may also be modified under fc->lock, tested under both)
325 */
326struct fuse_req {
327 /** This can be on either pending processing or io lists in
328 fuse_conn */
329 struct list_head list;
330
331 /** Entry on the interrupts list */
332 struct list_head intr_entry;
333
334 /* Input/output arguments */
335 struct fuse_args *args;
336
337 /** refcount */
338 refcount_t count;
339
340 /* Request flags, updated with test/set/clear_bit() */
341 unsigned long flags;
342
343 /* The request input header */
344 struct {
345 struct fuse_in_header h;
346 } in;
347
348 /* The request output header */
349 struct {
350 struct fuse_out_header h;
351 } out;
352
353 /** Used to wake up the task waiting for completion of request*/
354 wait_queue_head_t waitq;
355
356#if IS_ENABLED(CONFIG_VIRTIO_FS)
357 /** virtio-fs's physically contiguous buffer for in and out args */
358 void *argbuf;
359#endif
360};
361
362struct fuse_iqueue;
363
364/**
365 * Input queue callbacks
366 *
367 * Input queue signalling is device-specific. For example, the /dev/fuse file
368 * uses fiq->waitq and fasync to wake processes that are waiting on queue
369 * readiness. These callbacks allow other device types to respond to input
370 * queue activity.
371 */
372struct fuse_iqueue_ops {
373 /**
374 * Signal that a forget has been queued
375 */
376 void (*wake_forget_and_unlock)(struct fuse_iqueue *fiq)
377 __releases(fiq->lock);
378
379 /**
380 * Signal that an INTERRUPT request has been queued
381 */
382 void (*wake_interrupt_and_unlock)(struct fuse_iqueue *fiq)
383 __releases(fiq->lock);
384
385 /**
386 * Signal that a request has been queued
387 */
388 void (*wake_pending_and_unlock)(struct fuse_iqueue *fiq)
389 __releases(fiq->lock);
390
391 /**
392 * Clean up when fuse_iqueue is destroyed
393 */
394 void (*release)(struct fuse_iqueue *fiq);
395};
396
397/** /dev/fuse input queue operations */
398extern const struct fuse_iqueue_ops fuse_dev_fiq_ops;
399
400struct fuse_iqueue {
401 /** Connection established */
402 unsigned connected;
403
404 /** Lock protecting accesses to members of this structure */
405 spinlock_t lock;
406
407 /** Readers of the connection are waiting on this */
408 wait_queue_head_t waitq;
409
410 /** The next unique request id */
411 u64 reqctr;
412
413 /** The list of pending requests */
414 struct list_head pending;
415
416 /** Pending interrupts */
417 struct list_head interrupts;
418
419 /** Queue of pending forgets */
420 struct fuse_forget_link forget_list_head;
421 struct fuse_forget_link *forget_list_tail;
422
423 /** Batching of FORGET requests (positive indicates FORGET batch) */
424 int forget_batch;
425
426 /** O_ASYNC requests */
427 struct fasync_struct *fasync;
428
429 /** Device-specific callbacks */
430 const struct fuse_iqueue_ops *ops;
431
432 /** Device-specific state */
433 void *priv;
434};
435
436#define FUSE_PQ_HASH_BITS 8
437#define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS)
438
439struct fuse_pqueue {
440 /** Connection established */
441 unsigned connected;
442
443 /** Lock protecting accessess to members of this structure */
444 spinlock_t lock;
445
446 /** Hash table of requests being processed */
447 struct list_head *processing;
448
449 /** The list of requests under I/O */
450 struct list_head io;
451};
452
453/**
454 * Fuse device instance
455 */
456struct fuse_dev {
457 /** Fuse connection for this device */
458 struct fuse_conn *fc;
459
460 /** Processing queue */
461 struct fuse_pqueue pq;
462
463 /** list entry on fc->devices */
464 struct list_head entry;
465};
466
467struct fuse_fs_context {
468 int fd;
469 unsigned int rootmode;
470 kuid_t user_id;
471 kgid_t group_id;
472 bool is_bdev:1;
473 bool fd_present:1;
474 bool rootmode_present:1;
475 bool user_id_present:1;
476 bool group_id_present:1;
477 bool default_permissions:1;
478 bool allow_other:1;
479 bool destroy:1;
480 bool no_control:1;
481 bool no_force_umount:1;
482 bool no_mount_options:1;
483 unsigned int max_read;
484 unsigned int blksize;
485 const char *subtype;
486
487 /* fuse_dev pointer to fill in, should contain NULL on entry */
488 void **fudptr;
489};
490
491/**
492 * A Fuse connection.
493 *
494 * This structure is created, when the filesystem is mounted, and is
495 * destroyed, when the client device is closed and the filesystem is
496 * unmounted.
497 */
498struct fuse_conn {
499 /** Lock protecting accessess to members of this structure */
500 spinlock_t lock;
501
502 /** Refcount */
503 refcount_t count;
504
505 /** Number of fuse_dev's */
506 atomic_t dev_count;
507
508 struct rcu_head rcu;
509
510 /** The user id for this mount */
511 kuid_t user_id;
512
513 /** The group id for this mount */
514 kgid_t group_id;
515
516 /** The pid namespace for this mount */
517 struct pid_namespace *pid_ns;
518
519 /** The user namespace for this mount */
520 struct user_namespace *user_ns;
521
522 /** Maximum read size */
523 unsigned max_read;
524
525 /** Maximum write size */
526 unsigned max_write;
527
528 /** Maxmum number of pages that can be used in a single request */
529 unsigned int max_pages;
530
531 /** Input queue */
532 struct fuse_iqueue iq;
533
534 /** The next unique kernel file handle */
535 atomic64_t khctr;
536
537 /** rbtree of fuse_files waiting for poll events indexed by ph */
538 struct rb_root polled_files;
539
540 /** Maximum number of outstanding background requests */
541 unsigned max_background;
542
543 /** Number of background requests at which congestion starts */
544 unsigned congestion_threshold;
545
546 /** Number of requests currently in the background */
547 unsigned num_background;
548
549 /** Number of background requests currently queued for userspace */
550 unsigned active_background;
551
552 /** The list of background requests set aside for later queuing */
553 struct list_head bg_queue;
554
555 /** Protects: max_background, congestion_threshold, num_background,
556 * active_background, bg_queue, blocked */
557 spinlock_t bg_lock;
558
559 /** Flag indicating that INIT reply has been received. Allocating
560 * any fuse request will be suspended until the flag is set */
561 int initialized;
562
563 /** Flag indicating if connection is blocked. This will be
564 the case before the INIT reply is received, and if there
565 are too many outstading backgrounds requests */
566 int blocked;
567
568 /** waitq for blocked connection */
569 wait_queue_head_t blocked_waitq;
570
571 /** Connection established, cleared on umount, connection
572 abort and device release */
573 unsigned connected;
574
575 /** Connection aborted via sysfs */
576 bool aborted;
577
578 /** Connection failed (version mismatch). Cannot race with
579 setting other bitfields since it is only set once in INIT
580 reply, before any other request, and never cleared */
581 unsigned conn_error:1;
582
583 /** Connection successful. Only set in INIT */
584 unsigned conn_init:1;
585
586 /** Do readpages asynchronously? Only set in INIT */
587 unsigned async_read:1;
588
589 /** Return an unique read error after abort. Only set in INIT */
590 unsigned abort_err:1;
591
592 /** Do not send separate SETATTR request before open(O_TRUNC) */
593 unsigned atomic_o_trunc:1;
594
595 /** Filesystem supports NFS exporting. Only set in INIT */
596 unsigned export_support:1;
597
598 /** write-back cache policy (default is write-through) */
599 unsigned writeback_cache:1;
600
601 /** allow parallel lookups and readdir (default is serialized) */
602 unsigned parallel_dirops:1;
603
604 /** handle fs handles killing suid/sgid/cap on write/chown/trunc */
605 unsigned handle_killpriv:1;
606
607 /** cache READLINK responses in page cache */
608 unsigned cache_symlinks:1;
609
610 /*
611 * The following bitfields are only for optimization purposes
612 * and hence races in setting them will not cause malfunction
613 */
614
615 /** Is open/release not implemented by fs? */
616 unsigned no_open:1;
617
618 /** Is opendir/releasedir not implemented by fs? */
619 unsigned no_opendir:1;
620
621 /** Is fsync not implemented by fs? */
622 unsigned no_fsync:1;
623
624 /** Is fsyncdir not implemented by fs? */
625 unsigned no_fsyncdir:1;
626
627 /** Is flush not implemented by fs? */
628 unsigned no_flush:1;
629
630 /** Is setxattr not implemented by fs? */
631 unsigned no_setxattr:1;
632
633 /** Is getxattr not implemented by fs? */
634 unsigned no_getxattr:1;
635
636 /** Is listxattr not implemented by fs? */
637 unsigned no_listxattr:1;
638
639 /** Is removexattr not implemented by fs? */
640 unsigned no_removexattr:1;
641
642 /** Are posix file locking primitives not implemented by fs? */
643 unsigned no_lock:1;
644
645 /** Is access not implemented by fs? */
646 unsigned no_access:1;
647
648 /** Is create not implemented by fs? */
649 unsigned no_create:1;
650
651 /** Is interrupt not implemented by fs? */
652 unsigned no_interrupt:1;
653
654 /** Is bmap not implemented by fs? */
655 unsigned no_bmap:1;
656
657 /** Is poll not implemented by fs? */
658 unsigned no_poll:1;
659
660 /** Do multi-page cached writes */
661 unsigned big_writes:1;
662
663 /** Don't apply umask to creation modes */
664 unsigned dont_mask:1;
665
666 /** Are BSD file locking primitives not implemented by fs? */
667 unsigned no_flock:1;
668
669 /** Is fallocate not implemented by fs? */
670 unsigned no_fallocate:1;
671
672 /** Is rename with flags implemented by fs? */
673 unsigned no_rename2:1;
674
675 /** Use enhanced/automatic page cache invalidation. */
676 unsigned auto_inval_data:1;
677
678 /** Filesystem is fully reponsible for page cache invalidation. */
679 unsigned explicit_inval_data:1;
680
681 /** Does the filesystem support readdirplus? */
682 unsigned do_readdirplus:1;
683
684 /** Does the filesystem want adaptive readdirplus? */
685 unsigned readdirplus_auto:1;
686
687 /** Does the filesystem support asynchronous direct-IO submission? */
688 unsigned async_dio:1;
689
690 /** Is lseek not implemented by fs? */
691 unsigned no_lseek:1;
692
693 /** Does the filesystem support posix acls? */
694 unsigned posix_acl:1;
695
696 /** Check permissions based on the file mode or not? */
697 unsigned default_permissions:1;
698
699 /** Allow other than the mounter user to access the filesystem ? */
700 unsigned allow_other:1;
701
702 /** Does the filesystem support copy_file_range? */
703 unsigned no_copy_file_range:1;
704
705 /* Send DESTROY request */
706 unsigned int destroy:1;
707
708 /* Delete dentries that have gone stale */
709 unsigned int delete_stale:1;
710
711 /** Do not create entry in fusectl fs */
712 unsigned int no_control:1;
713
714 /** Do not allow MNT_FORCE umount */
715 unsigned int no_force_umount:1;
716
717 /* Do not show mount options */
718 unsigned int no_mount_options:1;
719
720 /** The number of requests waiting for completion */
721 atomic_t num_waiting;
722
723 /** Negotiated minor version */
724 unsigned minor;
725
726 /** Entry on the fuse_conn_list */
727 struct list_head entry;
728
729 /** Device ID from super block */
730 dev_t dev;
731
732 /** Dentries in the control filesystem */
733 struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
734
735 /** number of dentries used in the above array */
736 int ctl_ndents;
737
738 /** Key for lock owner ID scrambling */
739 u32 scramble_key[4];
740
741 /** Version counter for attribute changes */
742 atomic64_t attr_version;
743
744 /** Called on final put */
745 void (*release)(struct fuse_conn *);
746
747 /** Super block for this connection. */
748 struct super_block *sb;
749
750 /** Read/write semaphore to hold when accessing sb. */
751 struct rw_semaphore killsb;
752
753 /** List of device instances belonging to this connection */
754 struct list_head devices;
755};
756
757static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
758{
759 return sb->s_fs_info;
760}
761
762static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
763{
764 return get_fuse_conn_super(inode->i_sb);
765}
766
767static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
768{
769 return container_of(inode, struct fuse_inode, inode);
770}
771
772static inline u64 get_node_id(struct inode *inode)
773{
774 return get_fuse_inode(inode)->nodeid;
775}
776
777static inline int invalid_nodeid(u64 nodeid)
778{
779 return !nodeid || nodeid == FUSE_ROOT_ID;
780}
781
782static inline u64 fuse_get_attr_version(struct fuse_conn *fc)
783{
784 return atomic64_read(&fc->attr_version);
785}
786
787/** Device operations */
788extern const struct file_operations fuse_dev_operations;
789
790extern const struct dentry_operations fuse_dentry_operations;
791extern const struct dentry_operations fuse_root_dentry_operations;
792
793/**
794 * Inode to nodeid comparison.
795 */
796int fuse_inode_eq(struct inode *inode, void *_nodeidp);
797
798/**
799 * Get a filled in inode
800 */
801struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
802 int generation, struct fuse_attr *attr,
803 u64 attr_valid, u64 attr_version);
804
805int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name,
806 struct fuse_entry_out *outarg, struct inode **inode);
807
808/**
809 * Send FORGET command
810 */
811void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
812 u64 nodeid, u64 nlookup);
813
814struct fuse_forget_link *fuse_alloc_forget(void);
815
816struct fuse_forget_link *fuse_dequeue_forget(struct fuse_iqueue *fiq,
817 unsigned int max,
818 unsigned int *countp);
819
820/*
821 * Initialize READ or READDIR request
822 */
823struct fuse_io_args {
824 union {
825 struct {
826 struct fuse_read_in in;
827 u64 attr_ver;
828 } read;
829 struct {
830 struct fuse_write_in in;
831 struct fuse_write_out out;
832 } write;
833 };
834 struct fuse_args_pages ap;
835 struct fuse_io_priv *io;
836 struct fuse_file *ff;
837};
838
839void fuse_read_args_fill(struct fuse_io_args *ia, struct file *file, loff_t pos,
840 size_t count, int opcode);
841
842
843/**
844 * Send OPEN or OPENDIR request
845 */
846int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
847
848struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
849void fuse_file_free(struct fuse_file *ff);
850void fuse_finish_open(struct inode *inode, struct file *file);
851
852void fuse_sync_release(struct fuse_inode *fi, struct fuse_file *ff, int flags);
853
854/**
855 * Send RELEASE or RELEASEDIR request
856 */
857void fuse_release_common(struct file *file, bool isdir);
858
859/**
860 * Send FSYNC or FSYNCDIR request
861 */
862int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
863 int datasync, int opcode);
864
865/**
866 * Notify poll wakeup
867 */
868int fuse_notify_poll_wakeup(struct fuse_conn *fc,
869 struct fuse_notify_poll_wakeup_out *outarg);
870
871/**
872 * Initialize file operations on a regular file
873 */
874void fuse_init_file_inode(struct inode *inode);
875
876/**
877 * Initialize inode operations on regular files and special files
878 */
879void fuse_init_common(struct inode *inode);
880
881/**
882 * Initialize inode and file operations on a directory
883 */
884void fuse_init_dir(struct inode *inode);
885
886/**
887 * Initialize inode operations on a symlink
888 */
889void fuse_init_symlink(struct inode *inode);
890
891/**
892 * Change attributes of an inode
893 */
894void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
895 u64 attr_valid, u64 attr_version);
896
897void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
898 u64 attr_valid);
899
900/**
901 * Initialize the client device
902 */
903int fuse_dev_init(void);
904
905/**
906 * Cleanup the client device
907 */
908void fuse_dev_cleanup(void);
909
910int fuse_ctl_init(void);
911void __exit fuse_ctl_cleanup(void);
912
913/**
914 * Simple request sending that does request allocation and freeing
915 */
916ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args);
917int fuse_simple_background(struct fuse_conn *fc, struct fuse_args *args,
918 gfp_t gfp_flags);
919
920/**
921 * End a finished request
922 */
923void fuse_request_end(struct fuse_conn *fc, struct fuse_req *req);
924
925/* Abort all requests */
926void fuse_abort_conn(struct fuse_conn *fc);
927void fuse_wait_aborted(struct fuse_conn *fc);
928
929/**
930 * Invalidate inode attributes
931 */
932void fuse_invalidate_attr(struct inode *inode);
933
934void fuse_invalidate_entry_cache(struct dentry *entry);
935
936void fuse_invalidate_atime(struct inode *inode);
937
938u64 entry_attr_timeout(struct fuse_entry_out *o);
939void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o);
940
941/**
942 * Acquire reference to fuse_conn
943 */
944struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
945
946/**
947 * Initialize fuse_conn
948 */
949void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns,
950 const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv);
951
952/**
953 * Release reference to fuse_conn
954 */
955void fuse_conn_put(struct fuse_conn *fc);
956
957struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc);
958struct fuse_dev *fuse_dev_alloc(void);
959void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc);
960void fuse_dev_free(struct fuse_dev *fud);
961void fuse_send_init(struct fuse_conn *fc);
962
963/**
964 * Fill in superblock and initialize fuse connection
965 * @sb: partially-initialized superblock to fill in
966 * @ctx: mount context
967 */
968int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx);
969
970/**
971 * Disassociate fuse connection from superblock and kill the superblock
972 *
973 * Calls kill_anon_super(), do not use with bdev mounts.
974 */
975void fuse_kill_sb_anon(struct super_block *sb);
976
977/**
978 * Add connection to control filesystem
979 */
980int fuse_ctl_add_conn(struct fuse_conn *fc);
981
982/**
983 * Remove connection from control filesystem
984 */
985void fuse_ctl_remove_conn(struct fuse_conn *fc);
986
987/**
988 * Is file type valid?
989 */
990int fuse_valid_type(int m);
991
992/**
993 * Is current process allowed to perform filesystem operation?
994 */
995int fuse_allow_current_process(struct fuse_conn *fc);
996
997u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
998
999void fuse_update_ctime(struct inode *inode);
1000
1001int fuse_update_attributes(struct inode *inode, struct file *file);
1002
1003void fuse_flush_writepages(struct inode *inode);
1004
1005void fuse_set_nowrite(struct inode *inode);
1006void fuse_release_nowrite(struct inode *inode);
1007
1008/**
1009 * File-system tells the kernel to invalidate cache for the given node id.
1010 */
1011int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
1012 loff_t offset, loff_t len);
1013
1014/**
1015 * File-system tells the kernel to invalidate parent attributes and
1016 * the dentry matching parent/name.
1017 *
1018 * If the child_nodeid is non-zero and:
1019 * - matches the inode number for the dentry matching parent/name,
1020 * - is not a mount point
1021 * - is a file or oan empty directory
1022 * then the dentry is unhashed (d_delete()).
1023 */
1024int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
1025 u64 child_nodeid, struct qstr *name);
1026
1027int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
1028 bool isdir);
1029
1030/**
1031 * fuse_direct_io() flags
1032 */
1033
1034/** If set, it is WRITE; otherwise - READ */
1035#define FUSE_DIO_WRITE (1 << 0)
1036
1037/** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */
1038#define FUSE_DIO_CUSE (1 << 1)
1039
1040ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
1041 loff_t *ppos, int flags);
1042long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1043 unsigned int flags);
1044long fuse_ioctl_common(struct file *file, unsigned int cmd,
1045 unsigned long arg, unsigned int flags);
1046__poll_t fuse_file_poll(struct file *file, poll_table *wait);
1047int fuse_dev_release(struct inode *inode, struct file *file);
1048
1049bool fuse_write_update_size(struct inode *inode, loff_t pos);
1050
1051int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
1052int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
1053
1054int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
1055 struct file *file);
1056
1057void fuse_set_initialized(struct fuse_conn *fc);
1058
1059void fuse_unlock_inode(struct inode *inode, bool locked);
1060bool fuse_lock_inode(struct inode *inode);
1061
1062int fuse_setxattr(struct inode *inode, const char *name, const void *value,
1063 size_t size, int flags);
1064ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
1065 size_t size);
1066ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
1067int fuse_removexattr(struct inode *inode, const char *name);
1068extern const struct xattr_handler *fuse_xattr_handlers[];
1069extern const struct xattr_handler *fuse_acl_xattr_handlers[];
1070extern const struct xattr_handler *fuse_no_acl_xattr_handlers[];
1071
1072struct posix_acl;
1073struct posix_acl *fuse_get_acl(struct inode *inode, int type);
1074int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type);
1075
1076
1077/* readdir.c */
1078int fuse_readdir(struct file *file, struct dir_context *ctx);
1079
1080/**
1081 * Return the number of bytes in an arguments list
1082 */
1083unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args);
1084
1085/**
1086 * Get the next unique ID for a request
1087 */
1088u64 fuse_get_unique(struct fuse_iqueue *fiq);
1089void fuse_free_conn(struct fuse_conn *fc);
1090
1091#endif /* _FS_FUSE_I_H */