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 /** Bias for fi->writectr, meaning new writepages must not be sent */
39 #define FUSE_NOWRITE INT_MIN
40
41 /** Maximum length of a filename, not including terminating null */
42
43 /* maximum, small enough for FUSE_MIN_READ_BUFFER*/
44 #define FUSE_NAME_LOW_MAX 1024
45 /* maximum, but needs a request buffer > FUSE_MIN_READ_BUFFER */
46 #define FUSE_NAME_MAX (PATH_MAX - 1)
47
48 /** Number of dentries for each connection in the control filesystem */
49 #define FUSE_CTL_NUM_DENTRIES 5
50
51 /* Frequency (in seconds) of request timeout checks, if opted into */
52 #define FUSE_TIMEOUT_TIMER_FREQ 15
53
54 /** Frequency (in jiffies) of request timeout checks, if opted into */
55 extern const unsigned long fuse_timeout_timer_freq;
56
57 /*
58 * Dentries invalidation workqueue period, in seconds. The value of this
59 * parameter shall be >= FUSE_DENTRY_INVAL_FREQ_MIN seconds, or 0 (zero), in
60 * which case no workqueue will be created.
61 */
62 extern unsigned inval_wq __read_mostly;
63
64 /** Maximum of max_pages received in init_out */
65 extern unsigned int fuse_max_pages_limit;
66 /*
67 * Default timeout (in seconds) for the server to reply to a request
68 * before the connection is aborted, if no timeout was specified on mount.
69 */
70 extern unsigned int fuse_default_req_timeout;
71 /*
72 * Max timeout (in seconds) for the server to reply to a request before
73 * the connection is aborted.
74 */
75 extern unsigned int fuse_max_req_timeout;
76
77 /** List of active connections */
78 extern struct list_head fuse_conn_list;
79
80 /** Global mutex protecting fuse_conn_list and the control filesystem */
81 extern struct mutex fuse_mutex;
82
83 /** Module parameters */
84 extern unsigned int max_user_bgreq;
85 extern unsigned int max_user_congthresh;
86
87 /* One forget request */
88 struct fuse_forget_link {
89 struct fuse_forget_one forget_one;
90 struct fuse_forget_link *next;
91 };
92
93 /* Submount lookup tracking */
94 struct fuse_submount_lookup {
95 /** Refcount */
96 refcount_t count;
97
98 /** Unique ID, which identifies the inode between userspace
99 * and kernel */
100 u64 nodeid;
101
102 /** The request used for sending the FORGET message */
103 struct fuse_forget_link *forget;
104 };
105
106 /** Container for data related to mapping to backing file */
107 struct fuse_backing {
108 struct file *file;
109 struct cred *cred;
110
111 /** refcount */
112 refcount_t count;
113 struct rcu_head rcu;
114 };
115
116 /** FUSE inode */
117 struct fuse_inode {
118 /** Inode data */
119 struct inode inode;
120
121 /** Unique ID, which identifies the inode between userspace
122 * and kernel */
123 u64 nodeid;
124
125 /** Number of lookups on this inode */
126 u64 nlookup;
127
128 /** The request used for sending the FORGET message */
129 struct fuse_forget_link *forget;
130
131 /** Time in jiffies until the file attributes are valid */
132 u64 i_time;
133
134 /* Which attributes are invalid */
135 u32 inval_mask;
136
137 /** The sticky bit in inode->i_mode may have been removed, so
138 preserve the original mode */
139 umode_t orig_i_mode;
140
141 /* Cache birthtime */
142 struct timespec64 i_btime;
143
144 /** 64 bit inode number */
145 u64 orig_ino;
146
147 /** Version of last attribute change */
148 u64 attr_version;
149
150 union {
151 /* read/write io cache (regular file only) */
152 struct {
153 /* Files usable in writepage. Protected by fi->lock */
154 struct list_head write_files;
155
156 /* Writepages pending on truncate or fsync */
157 struct list_head queued_writes;
158
159 /* Number of sent writes, a negative bias
160 * (FUSE_NOWRITE) means more writes are blocked */
161 int writectr;
162
163 /** Number of files/maps using page cache */
164 int iocachectr;
165
166 /* Waitq for writepage completion */
167 wait_queue_head_t page_waitq;
168
169 /* waitq for direct-io completion */
170 wait_queue_head_t direct_io_waitq;
171 };
172
173 /* readdir cache (directory only) */
174 struct {
175 /* true if fully cached */
176 bool cached;
177
178 /* size of cache */
179 loff_t size;
180
181 /* position at end of cache (position of next entry) */
182 loff_t pos;
183
184 /* version of the cache */
185 u64 version;
186
187 /* modification time of directory when cache was
188 * started */
189 struct timespec64 mtime;
190
191 /* iversion of directory when cache was started */
192 u64 iversion;
193
194 /* protects above fields */
195 spinlock_t lock;
196 } rdc;
197 };
198
199 /** Miscellaneous bits describing inode state */
200 unsigned long state;
201
202 /** Lock for serializing lookup and readdir for back compatibility*/
203 struct mutex mutex;
204
205 /** Lock to protect write related fields */
206 spinlock_t lock;
207
208 #ifdef CONFIG_FUSE_DAX
209 /*
210 * Dax specific inode data
211 */
212 struct fuse_inode_dax *dax;
213 #endif
214 /** Submount specific lookup tracking */
215 struct fuse_submount_lookup *submount_lookup;
216 #ifdef CONFIG_FUSE_PASSTHROUGH
217 /** Reference to backing file in passthrough mode */
218 struct fuse_backing *fb;
219 #endif
220
221 /*
222 * The underlying inode->i_blkbits value will not be modified,
223 * so preserve the blocksize specified by the server.
224 */
225 u8 cached_i_blkbits;
226 };
227
228 /** FUSE inode state bits */
229 enum {
230 /** Advise readdirplus */
231 FUSE_I_ADVISE_RDPLUS,
232 /** Initialized with readdirplus */
233 FUSE_I_INIT_RDPLUS,
234 /** An operation changing file size is in progress */
235 FUSE_I_SIZE_UNSTABLE,
236 /* Bad inode */
237 FUSE_I_BAD,
238 /* Has btime */
239 FUSE_I_BTIME,
240 /* Wants or already has page cache IO */
241 FUSE_I_CACHE_IO_MODE,
242 /*
243 * Client has exclusive access to the inode, either because fs is local
244 * or the fuse server has an exclusive "lease" on distributed fs
245 */
246 FUSE_I_EXCLUSIVE,
247 };
248
249 struct fuse_conn;
250 struct fuse_mount;
251 union fuse_file_args;
252
253 /** FUSE specific file data */
254 struct fuse_file {
255 /** Fuse connection for this file */
256 struct fuse_mount *fm;
257
258 /* Argument space reserved for open/release */
259 union fuse_file_args *args;
260
261 /** Kernel file handle guaranteed to be unique */
262 u64 kh;
263
264 /** File handle used by userspace */
265 u64 fh;
266
267 /** Node id of this file */
268 u64 nodeid;
269
270 /** Refcount */
271 refcount_t count;
272
273 /** FOPEN_* flags returned by open */
274 u32 open_flags;
275
276 /** Entry on inode's write_files list */
277 struct list_head write_entry;
278
279 /* Readdir related */
280 struct {
281 /* Dir stream position */
282 loff_t pos;
283
284 /* Offset in cache */
285 loff_t cache_off;
286
287 /* Version of cache we are reading */
288 u64 version;
289
290 } readdir;
291
292 /** RB node to be linked on fuse_conn->polled_files */
293 struct rb_node polled_node;
294
295 /** Wait queue head for poll */
296 wait_queue_head_t poll_wait;
297
298 /** Does file hold a fi->iocachectr refcount? */
299 enum { IOM_NONE, IOM_CACHED, IOM_UNCACHED } iomode;
300
301 #ifdef CONFIG_FUSE_PASSTHROUGH
302 /** Reference to backing file in passthrough mode */
303 struct file *passthrough;
304 const struct cred *cred;
305 #endif
306
307 /** Has flock been performed on this file? */
308 bool flock:1;
309 };
310
311 /** One input argument of a request */
312 struct fuse_in_arg {
313 unsigned size;
314 const void *value;
315 };
316
317 /** One output argument of a request */
318 struct fuse_arg {
319 unsigned size;
320 void *value;
321 };
322
323 /** FUSE folio descriptor */
324 struct fuse_folio_desc {
325 unsigned int length;
326 unsigned int offset;
327 };
328
329 struct fuse_args {
330 uint64_t nodeid;
331 uint32_t opcode;
332 uint8_t in_numargs;
333 uint8_t out_numargs;
334 uint8_t ext_idx;
335 bool force:1;
336 bool noreply:1;
337 bool nocreds:1;
338 bool in_pages:1;
339 bool out_pages:1;
340 bool user_pages:1;
341 bool out_argvar:1;
342 bool page_zeroing:1;
343 bool page_replace:1;
344 bool may_block:1;
345 bool is_ext:1;
346 bool is_pinned:1;
347 bool invalidate_vmap:1;
348 bool abort_on_kill:1;
349 struct fuse_in_arg in_args[4];
350 struct fuse_arg out_args[2];
351 void (*end)(struct fuse_mount *fm, struct fuse_args *args, int error);
352 /* Used for kvec iter backed by vmalloc address */
353 void *vmap_base;
354 };
355
356 struct fuse_args_pages {
357 struct fuse_args args;
358 struct folio **folios;
359 struct fuse_folio_desc *descs;
360 unsigned int num_folios;
361 };
362
363 struct fuse_release_args {
364 struct fuse_args args;
365 struct fuse_release_in inarg;
366 struct inode *inode;
367 };
368
369 union fuse_file_args {
370 /* Used during open() */
371 struct fuse_open_out open_outarg;
372 /* Used during release() */
373 struct fuse_release_args release_args;
374 };
375
376 #define FUSE_ARGS(args) struct fuse_args args = {}
377
378 /** The request IO state (for asynchronous processing) */
379 struct fuse_io_priv {
380 struct kref refcnt;
381 int async;
382 spinlock_t lock;
383 unsigned reqs;
384 ssize_t bytes;
385 size_t size;
386 __u64 offset;
387 bool write;
388 bool should_dirty;
389 int err;
390 struct kiocb *iocb;
391 struct completion *done;
392 bool blocking;
393 };
394
395 #define FUSE_IO_PRIV_SYNC(i) \
396 { \
397 .refcnt = KREF_INIT(1), \
398 .async = 0, \
399 .iocb = i, \
400 }
401
402 /**
403 * Request flags
404 *
405 * FR_ISREPLY: set if the request has reply
406 * FR_FORCE: force sending of the request even if interrupted
407 * FR_BACKGROUND: request is sent in the background
408 * FR_WAITING: request is counted as "waiting"
409 * FR_ABORTED: the request was aborted
410 * FR_INTERRUPTED: the request has been interrupted
411 * FR_LOCKED: data is being copied to/from the request
412 * FR_PENDING: request is not yet in userspace
413 * FR_SENT: request is in userspace, waiting for an answer
414 * FR_FINISHED: request is finished
415 * FR_PRIVATE: request is on private list
416 * FR_ASYNC: request is asynchronous
417 * FR_URING: request is handled through fuse-io-uring
418 */
419 enum fuse_req_flag {
420 FR_ISREPLY,
421 FR_FORCE,
422 FR_BACKGROUND,
423 FR_WAITING,
424 FR_ABORTED,
425 FR_INTERRUPTED,
426 FR_LOCKED,
427 FR_PENDING,
428 FR_SENT,
429 FR_FINISHED,
430 FR_PRIVATE,
431 FR_ASYNC,
432 FR_URING,
433 };
434
435 /**
436 * A request to the client
437 *
438 * .waitq.lock protects the following fields:
439 * - FR_ABORTED
440 * - FR_LOCKED (may also be modified under fc->lock, tested under both)
441 */
442 struct fuse_req {
443 /** This can be on either pending processing or io lists in
444 fuse_conn */
445 struct list_head list;
446
447 /** Entry on the interrupts list */
448 struct list_head intr_entry;
449
450 /* Input/output arguments */
451 struct fuse_args *args;
452
453 /** refcount */
454 refcount_t count;
455
456 /* Request flags, updated with test/set/clear_bit() */
457 unsigned long flags;
458
459 /* The request input header */
460 struct {
461 struct fuse_in_header h;
462 } in;
463
464 /* The request output header */
465 struct {
466 struct fuse_out_header h;
467 } out;
468
469 /** Used to wake up the task waiting for completion of request*/
470 wait_queue_head_t waitq;
471
472 #if IS_ENABLED(CONFIG_VIRTIO_FS)
473 /** virtio-fs's physically contiguous buffer for in and out args */
474 void *argbuf;
475 #endif
476
477 /** fuse_mount this request belongs to */
478 struct fuse_mount *fm;
479
480 #ifdef CONFIG_FUSE_IO_URING
481 void *ring_entry;
482 void *ring_queue;
483 #endif
484 /** When (in jiffies) the request was created */
485 unsigned long create_time;
486 };
487
488 struct fuse_iqueue;
489
490 /**
491 * Input queue callbacks
492 *
493 * Input queue signalling is device-specific. For example, the /dev/fuse file
494 * uses fiq->waitq and fasync to wake processes that are waiting on queue
495 * readiness. These callbacks allow other device types to respond to input
496 * queue activity.
497 */
498 struct fuse_iqueue_ops {
499 /**
500 * Send one forget
501 */
502 void (*send_forget)(struct fuse_iqueue *fiq, struct fuse_forget_link *link);
503
504 /**
505 * Send interrupt for request
506 */
507 void (*send_interrupt)(struct fuse_iqueue *fiq, struct fuse_req *req);
508
509 /**
510 * Send one request
511 */
512 void (*send_req)(struct fuse_iqueue *fiq, struct fuse_req *req);
513
514 /**
515 * Clean up when fuse_iqueue is destroyed
516 */
517 void (*release)(struct fuse_iqueue *fiq);
518 };
519
520 /** /dev/fuse input queue operations */
521 extern const struct fuse_iqueue_ops fuse_dev_fiq_ops;
522
523 struct fuse_iqueue {
524 /** Connection established */
525 unsigned connected;
526
527 /** Lock protecting accesses to members of this structure */
528 spinlock_t lock;
529
530 /** Readers of the connection are waiting on this */
531 wait_queue_head_t waitq;
532
533 /** The next unique request id */
534 u64 reqctr;
535
536 /** The list of pending requests */
537 struct list_head pending;
538
539 /** Pending interrupts */
540 struct list_head interrupts;
541
542 /** Queue of pending forgets */
543 struct fuse_forget_link forget_list_head;
544 struct fuse_forget_link *forget_list_tail;
545
546 /** Batching of FORGET requests (positive indicates FORGET batch) */
547 int forget_batch;
548
549 /** O_ASYNC requests */
550 struct fasync_struct *fasync;
551
552 /** Device-specific callbacks */
553 const struct fuse_iqueue_ops *ops;
554
555 /** Device-specific state */
556 void *priv;
557 };
558
559 #define FUSE_PQ_HASH_BITS 8
560 #define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS)
561
562 struct fuse_pqueue {
563 /** Connection established */
564 unsigned connected;
565
566 /** Lock protecting accessess to members of this structure */
567 spinlock_t lock;
568
569 /** Hash table of requests being processed */
570 struct list_head *processing;
571
572 /** The list of requests under I/O */
573 struct list_head io;
574 };
575
576 /**
577 * Fuse device instance
578 */
579 struct fuse_dev {
580 /** Reference count of this object */
581 refcount_t ref;
582
583 /** Issue FUSE_INIT synchronously */
584 bool sync_init;
585
586 /** Fuse connection for this device */
587 struct fuse_conn *fc;
588
589 /** Processing queue */
590 struct fuse_pqueue pq;
591
592 /** list entry on fc->devices */
593 struct list_head entry;
594 };
595
596 enum fuse_dax_mode {
597 FUSE_DAX_INODE_DEFAULT, /* default */
598 FUSE_DAX_ALWAYS, /* "-o dax=always" */
599 FUSE_DAX_NEVER, /* "-o dax=never" */
600 FUSE_DAX_INODE_USER, /* "-o dax=inode" */
601 };
602
fuse_is_inode_dax_mode(enum fuse_dax_mode mode)603 static inline bool fuse_is_inode_dax_mode(enum fuse_dax_mode mode)
604 {
605 return mode == FUSE_DAX_INODE_DEFAULT || mode == FUSE_DAX_INODE_USER;
606 }
607
608 struct fuse_fs_context {
609 struct fuse_dev *fud;
610 unsigned int rootmode;
611 kuid_t user_id;
612 kgid_t group_id;
613 bool is_bdev:1;
614 bool rootmode_present:1;
615 bool user_id_present:1;
616 bool group_id_present:1;
617 bool default_permissions:1;
618 bool allow_other:1;
619 bool destroy:1;
620 bool no_control:1;
621 bool no_force_umount:1;
622 bool legacy_opts_show:1;
623 enum fuse_dax_mode dax_mode;
624 unsigned int max_read;
625 unsigned int blksize;
626 const char *subtype;
627
628 /* DAX device, may be NULL */
629 struct dax_device *dax_dev;
630 };
631
632 struct fuse_sync_bucket {
633 /* count is a possible scalability bottleneck */
634 atomic_t count;
635 wait_queue_head_t waitq;
636 struct rcu_head rcu;
637 };
638
639 /**
640 * A Fuse connection.
641 *
642 * This structure is created, when the root filesystem is mounted, and
643 * is destroyed, when the client device is closed and the last
644 * fuse_mount is destroyed.
645 */
646 struct fuse_conn {
647 /** Lock protecting accessess to members of this structure */
648 spinlock_t lock;
649
650 /** Refcount */
651 refcount_t count;
652
653 /** Current epoch for up-to-date dentries */
654 atomic_t epoch;
655
656 struct work_struct epoch_work;
657
658 struct rcu_head rcu;
659
660 /** The user id for this mount */
661 kuid_t user_id;
662
663 /** The group id for this mount */
664 kgid_t group_id;
665
666 /** The pid namespace for this mount */
667 struct pid_namespace *pid_ns;
668
669 /** The user namespace for this mount */
670 struct user_namespace *user_ns;
671
672 /** Maximum read size */
673 unsigned max_read;
674
675 /** Maximum write size */
676 unsigned max_write;
677
678 /** Maximum number of pages that can be used in a single request */
679 unsigned int max_pages;
680
681 /** Constrain ->max_pages to this value during feature negotiation */
682 unsigned int max_pages_limit;
683
684 /** Input queue */
685 struct fuse_iqueue iq;
686
687 /** The next unique kernel file handle */
688 atomic64_t khctr;
689
690 /** rbtree of fuse_files waiting for poll events indexed by ph */
691 struct rb_root polled_files;
692
693 /** Maximum number of outstanding background requests */
694 unsigned max_background;
695
696 /** Number of background requests at which congestion starts */
697 unsigned congestion_threshold;
698
699 /** Number of requests currently in the background */
700 unsigned num_background;
701
702 /** Number of background requests currently queued for userspace */
703 unsigned active_background;
704
705 /** The list of background requests set aside for later queuing */
706 struct list_head bg_queue;
707
708 /** Protects: max_background, congestion_threshold, num_background,
709 * active_background, bg_queue, blocked */
710 spinlock_t bg_lock;
711
712 /** Flag indicating that INIT reply has been received. Allocating
713 * any fuse request will be suspended until the flag is set */
714 int initialized;
715
716 /** Flag indicating if connection is blocked. This will be
717 the case before the INIT reply is received, and if there
718 are too many outstading backgrounds requests */
719 int blocked;
720
721 /** waitq for blocked connection */
722 wait_queue_head_t blocked_waitq;
723
724 /** Connection established, cleared on umount, connection
725 abort and device release */
726 unsigned connected;
727
728 /** Connection aborted via sysfs */
729 bool aborted;
730
731 /** Connection failed (version mismatch). Cannot race with
732 setting other bitfields since it is only set once in INIT
733 reply, before any other request, and never cleared */
734 unsigned conn_error:1;
735
736 /** Connection successful. Only set in INIT */
737 unsigned conn_init:1;
738
739 /** Do readahead asynchronously? Only set in INIT */
740 unsigned async_read:1;
741
742 /** Return an unique read error after abort. Only set in INIT */
743 unsigned abort_err:1;
744
745 /** Do not send separate SETATTR request before open(O_TRUNC) */
746 unsigned atomic_o_trunc:1;
747
748 /** Filesystem supports NFS exporting. Only set in INIT */
749 unsigned export_support:1;
750
751 /** write-back cache policy (default is write-through) */
752 unsigned writeback_cache:1;
753
754 /** allow parallel lookups and readdir (default is serialized) */
755 unsigned parallel_dirops:1;
756
757 /** handle fs handles killing suid/sgid/cap on write/chown/trunc */
758 unsigned handle_killpriv:1;
759
760 /** cache READLINK responses in page cache */
761 unsigned cache_symlinks:1;
762
763 /* show legacy mount options */
764 unsigned int legacy_opts_show:1;
765
766 /*
767 * fs kills suid/sgid/cap on write/chown/trunc. suid is killed on
768 * write/trunc only if caller did not have CAP_FSETID. sgid is killed
769 * on write/truncate only if caller did not have CAP_FSETID as well as
770 * file has group execute permission.
771 */
772 unsigned handle_killpriv_v2:1;
773
774 /*
775 * The following bitfields are only for optimization purposes
776 * and hence races in setting them will not cause malfunction
777 */
778
779 /** Is open/release not implemented by fs? */
780 unsigned no_open:1;
781
782 /** Is opendir/releasedir not implemented by fs? */
783 unsigned no_opendir:1;
784
785 /** Is fsync not implemented by fs? */
786 unsigned no_fsync:1;
787
788 /** Is fsyncdir not implemented by fs? */
789 unsigned no_fsyncdir:1;
790
791 /** Is flush not implemented by fs? */
792 unsigned no_flush:1;
793
794 /** Is setxattr not implemented by fs? */
795 unsigned no_setxattr:1;
796
797 /** Does file server support extended setxattr */
798 unsigned setxattr_ext:1;
799
800 /** Is getxattr not implemented by fs? */
801 unsigned no_getxattr:1;
802
803 /** Is listxattr not implemented by fs? */
804 unsigned no_listxattr:1;
805
806 /** Is removexattr not implemented by fs? */
807 unsigned no_removexattr:1;
808
809 /** Are posix file locking primitives not implemented by fs? */
810 unsigned no_lock:1;
811
812 /** Is access not implemented by fs? */
813 unsigned no_access:1;
814
815 /** Is create not implemented by fs? */
816 unsigned no_create:1;
817
818 /** Is interrupt not implemented by fs? */
819 unsigned no_interrupt:1;
820
821 /** Is bmap not implemented by fs? */
822 unsigned no_bmap:1;
823
824 /** Is poll not implemented by fs? */
825 unsigned no_poll:1;
826
827 /** Do multi-page cached writes */
828 unsigned big_writes:1;
829
830 /** Don't apply umask to creation modes */
831 unsigned dont_mask:1;
832
833 /** Are BSD file locking primitives not implemented by fs? */
834 unsigned no_flock:1;
835
836 /** Is fallocate not implemented by fs? */
837 unsigned no_fallocate:1;
838
839 /** Is rename with flags implemented by fs? */
840 unsigned no_rename2:1;
841
842 /** Use enhanced/automatic page cache invalidation. */
843 unsigned auto_inval_data:1;
844
845 /** Filesystem is fully responsible for page cache invalidation. */
846 unsigned explicit_inval_data:1;
847
848 /** Does the filesystem support readdirplus? */
849 unsigned do_readdirplus:1;
850
851 /** Does the filesystem want adaptive readdirplus? */
852 unsigned readdirplus_auto:1;
853
854 /** Does the filesystem support asynchronous direct-IO submission? */
855 unsigned async_dio:1;
856
857 /** Is lseek not implemented by fs? */
858 unsigned no_lseek:1;
859
860 /** Does the filesystem support posix acls? */
861 unsigned posix_acl:1;
862
863 /** Check permissions based on the file mode or not? */
864 unsigned default_permissions:1;
865
866 /** Allow other than the mounter user to access the filesystem ? */
867 unsigned allow_other:1;
868
869 /** Does the filesystem support copy_file_range? */
870 unsigned no_copy_file_range:1;
871
872 /** Does the filesystem support copy_file_range_64? */
873 unsigned no_copy_file_range_64:1;
874
875 /* Send DESTROY request */
876 unsigned int destroy:1;
877
878 /* Delete dentries that have gone stale */
879 unsigned int delete_stale:1;
880
881 /** Do not create entry in fusectl fs */
882 unsigned int no_control:1;
883
884 /** Do not allow MNT_FORCE umount */
885 unsigned int no_force_umount:1;
886
887 /* Auto-mount submounts announced by the server */
888 unsigned int auto_submounts:1;
889
890 /* Propagate syncfs() to server */
891 unsigned int sync_fs:1;
892
893 /* Initialize security xattrs when creating a new inode */
894 unsigned int init_security:1;
895
896 /* Add supplementary group info when creating a new inode */
897 unsigned int create_supp_group:1;
898
899 /* Does the filesystem support per inode DAX? */
900 unsigned int inode_dax:1;
901
902 /* Is tmpfile not implemented by fs? */
903 unsigned int no_tmpfile:1;
904
905 /* Relax restrictions to allow shared mmap in FOPEN_DIRECT_IO mode */
906 unsigned int direct_io_allow_mmap:1;
907
908 /* Is statx not implemented by fs? */
909 unsigned int no_statx:1;
910
911 /** Passthrough support for read/write IO */
912 unsigned int passthrough:1;
913
914 /* Use pages instead of pointer for kernel I/O */
915 unsigned int use_pages_for_kvec_io:1;
916
917 /* Is link not implemented by fs? */
918 unsigned int no_link:1;
919
920 /* Is synchronous FUSE_INIT allowed? */
921 unsigned int sync_init:1;
922
923 /* Use io_uring for communication */
924 unsigned int io_uring;
925
926 /** Maximum stack depth for passthrough backing files */
927 int max_stack_depth;
928
929 /** The number of requests waiting for completion */
930 atomic_t num_waiting;
931
932 /** Negotiated minor version */
933 unsigned minor;
934
935 /** Entry on the fuse_conn_list */
936 struct list_head entry;
937
938 /** Device ID from the root super block */
939 dev_t dev;
940
941 /** Key for lock owner ID scrambling */
942 u32 scramble_key[4];
943
944 /** Version counter for attribute changes */
945 atomic64_t attr_version;
946
947 /** Version counter for evict inode */
948 atomic64_t evict_ctr;
949
950 /* maximum file name length */
951 u32 name_max;
952
953 /** Called on final put */
954 void (*release)(struct fuse_conn *);
955
956 /**
957 * Read/write semaphore to hold when accessing the sb of any
958 * fuse_mount belonging to this connection
959 */
960 struct rw_semaphore killsb;
961
962 /** List of device instances belonging to this connection */
963 struct list_head devices;
964
965 #ifdef CONFIG_FUSE_DAX
966 /* Dax mode */
967 enum fuse_dax_mode dax_mode;
968
969 /* Dax specific conn data, non-NULL if DAX is enabled */
970 struct fuse_conn_dax *dax;
971 #endif
972
973 /** List of filesystems using this connection */
974 struct list_head mounts;
975
976 /* New writepages go into this bucket */
977 struct fuse_sync_bucket __rcu *curr_bucket;
978
979 #ifdef CONFIG_FUSE_PASSTHROUGH
980 /** IDR for backing files ids */
981 struct idr backing_files_map;
982 #endif
983
984 #ifdef CONFIG_FUSE_IO_URING
985 /** uring connection information*/
986 struct fuse_ring *ring;
987 #endif
988
989 /** Only used if the connection opts into request timeouts */
990 struct {
991 /* Worker for checking if any requests have timed out */
992 struct delayed_work work;
993
994 /* Request timeout (in jiffies). 0 = no timeout */
995 unsigned int req_timeout;
996 } timeout;
997 };
998
999 /*
1000 * Represents a mounted filesystem, potentially a submount.
1001 *
1002 * This object allows sharing a fuse_conn between separate mounts to
1003 * allow submounts with dedicated superblocks and thus separate device
1004 * IDs.
1005 */
1006 struct fuse_mount {
1007 /* Underlying (potentially shared) connection to the FUSE server */
1008 struct fuse_conn *fc;
1009
1010 /*
1011 * Super block for this connection (fc->killsb must be held when
1012 * accessing this).
1013 */
1014 struct super_block *sb;
1015
1016 /* Entry on fc->mounts */
1017 struct list_head fc_entry;
1018 struct rcu_head rcu;
1019 };
1020
1021 /*
1022 * Empty header for FUSE opcodes without specific header needs.
1023 * Used as a placeholder in args->in_args[0] for consistency
1024 * across all FUSE operations, simplifying request handling.
1025 */
1026 struct fuse_zero_header {};
1027
fuse_set_zero_arg0(struct fuse_args * args)1028 static inline void fuse_set_zero_arg0(struct fuse_args *args)
1029 {
1030 args->in_args[0].size = sizeof(struct fuse_zero_header);
1031 args->in_args[0].value = NULL;
1032 }
1033
get_fuse_mount_super(struct super_block * sb)1034 static inline struct fuse_mount *get_fuse_mount_super(struct super_block *sb)
1035 {
1036 return sb->s_fs_info;
1037 }
1038
get_fuse_conn_super(struct super_block * sb)1039 static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
1040 {
1041 return get_fuse_mount_super(sb)->fc;
1042 }
1043
get_fuse_mount(struct inode * inode)1044 static inline struct fuse_mount *get_fuse_mount(struct inode *inode)
1045 {
1046 return get_fuse_mount_super(inode->i_sb);
1047 }
1048
get_fuse_conn(struct inode * inode)1049 static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
1050 {
1051 return get_fuse_mount_super(inode->i_sb)->fc;
1052 }
1053
get_fuse_inode(const struct inode * inode)1054 static inline struct fuse_inode *get_fuse_inode(const struct inode *inode)
1055 {
1056 return container_of(inode, struct fuse_inode, inode);
1057 }
1058
get_node_id(struct inode * inode)1059 static inline u64 get_node_id(struct inode *inode)
1060 {
1061 return get_fuse_inode(inode)->nodeid;
1062 }
1063
invalid_nodeid(u64 nodeid)1064 static inline int invalid_nodeid(u64 nodeid)
1065 {
1066 return !nodeid || nodeid == FUSE_ROOT_ID;
1067 }
1068
fuse_get_attr_version(struct fuse_conn * fc)1069 static inline u64 fuse_get_attr_version(struct fuse_conn *fc)
1070 {
1071 return atomic64_read(&fc->attr_version);
1072 }
1073
fuse_get_evict_ctr(struct fuse_conn * fc)1074 static inline u64 fuse_get_evict_ctr(struct fuse_conn *fc)
1075 {
1076 return atomic64_read(&fc->evict_ctr);
1077 }
1078
fuse_stale_inode(const struct inode * inode,int generation,struct fuse_attr * attr)1079 static inline bool fuse_stale_inode(const struct inode *inode, int generation,
1080 struct fuse_attr *attr)
1081 {
1082 return inode->i_generation != generation ||
1083 inode_wrong_type(inode, attr->mode);
1084 }
1085
fuse_make_bad(struct inode * inode)1086 static inline void fuse_make_bad(struct inode *inode)
1087 {
1088 set_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state);
1089 }
1090
fuse_is_bad(struct inode * inode)1091 static inline bool fuse_is_bad(struct inode *inode)
1092 {
1093 return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state));
1094 }
1095
fuse_inode_is_exclusive(const struct inode * inode)1096 static inline bool fuse_inode_is_exclusive(const struct inode *inode)
1097 {
1098 const struct fuse_inode *fi = get_fuse_inode(inode);
1099
1100 return test_bit(FUSE_I_EXCLUSIVE, &fi->state);
1101 }
1102
fuse_folios_alloc(unsigned int nfolios,gfp_t flags,struct fuse_folio_desc ** desc)1103 static inline struct folio **fuse_folios_alloc(unsigned int nfolios, gfp_t flags,
1104 struct fuse_folio_desc **desc)
1105 {
1106 struct folio **folios;
1107
1108 folios = kzalloc(nfolios * (sizeof(struct folio *) +
1109 sizeof(struct fuse_folio_desc)), flags);
1110 *desc = (void *) (folios + nfolios);
1111
1112 return folios;
1113 }
1114
fuse_folio_descs_length_init(struct fuse_folio_desc * descs,unsigned int index,unsigned int nr_folios)1115 static inline void fuse_folio_descs_length_init(struct fuse_folio_desc *descs,
1116 unsigned int index,
1117 unsigned int nr_folios)
1118 {
1119 int i;
1120
1121 for (i = index; i < index + nr_folios; i++)
1122 descs[i].length = PAGE_SIZE - descs[i].offset;
1123 }
1124
fuse_sync_bucket_dec(struct fuse_sync_bucket * bucket)1125 static inline void fuse_sync_bucket_dec(struct fuse_sync_bucket *bucket)
1126 {
1127 /* Need RCU protection to prevent use after free after the decrement */
1128 rcu_read_lock();
1129 if (atomic_dec_and_test(&bucket->count))
1130 wake_up(&bucket->waitq);
1131 rcu_read_unlock();
1132 }
1133
1134 /** Device operations */
1135 extern const struct file_operations fuse_dev_operations;
1136
1137 extern const struct dentry_operations fuse_dentry_operations;
1138
1139 /**
1140 * Get a filled in inode
1141 */
1142 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
1143 int generation, struct fuse_attr *attr,
1144 u64 attr_valid, u64 attr_version,
1145 u64 evict_ctr);
1146
1147 int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name,
1148 struct fuse_entry_out *outarg, struct inode **inode);
1149
1150 /**
1151 * Send FORGET command
1152 */
1153 void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
1154 u64 nodeid, u64 nlookup);
1155
1156 struct fuse_forget_link *fuse_alloc_forget(void);
1157
1158 /*
1159 * Initialize READ or READDIR request
1160 */
1161 struct fuse_io_args {
1162 union {
1163 struct {
1164 struct fuse_read_in in;
1165 u64 attr_ver;
1166 } read;
1167 struct {
1168 struct fuse_write_in in;
1169 struct fuse_write_out out;
1170 bool folio_locked;
1171 } write;
1172 };
1173 struct fuse_args_pages ap;
1174 struct fuse_io_priv *io;
1175 struct fuse_file *ff;
1176 };
1177
1178 void fuse_read_args_fill(struct fuse_io_args *ia, struct file *file, loff_t pos,
1179 size_t count, int opcode);
1180
1181
1182 struct fuse_file *fuse_file_alloc(struct fuse_mount *fm, bool release);
1183 void fuse_file_free(struct fuse_file *ff);
1184 int fuse_finish_open(struct inode *inode, struct file *file);
1185
1186 void fuse_sync_release(struct fuse_inode *fi, struct fuse_file *ff,
1187 unsigned int flags);
1188
1189 /**
1190 * Send RELEASE or RELEASEDIR request
1191 */
1192 void fuse_release_common(struct file *file, bool isdir);
1193
1194 /**
1195 * Send FSYNC or FSYNCDIR request
1196 */
1197 int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
1198 int datasync, int opcode);
1199
1200 /**
1201 * Notify poll wakeup
1202 */
1203 int fuse_notify_poll_wakeup(struct fuse_conn *fc,
1204 struct fuse_notify_poll_wakeup_out *outarg);
1205
1206 /**
1207 * Initialize file operations on a regular file
1208 */
1209 void fuse_init_file_inode(struct inode *inode, unsigned int flags);
1210
1211 /**
1212 * Initialize inode operations on regular files and special files
1213 */
1214 void fuse_init_common(struct inode *inode);
1215
1216 /**
1217 * Initialize inode and file operations on a directory
1218 */
1219 void fuse_init_dir(struct inode *inode);
1220
1221 /**
1222 * Initialize inode operations on a symlink
1223 */
1224 void fuse_init_symlink(struct inode *inode);
1225
1226 /**
1227 * Change attributes of an inode
1228 */
1229 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
1230 struct fuse_statx *sx,
1231 u64 attr_valid, u64 attr_version);
1232
1233 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
1234 struct fuse_statx *sx,
1235 u64 attr_valid, u32 cache_mask,
1236 u64 evict_ctr);
1237
1238 u32 fuse_get_cache_mask(struct inode *inode);
1239
1240 /**
1241 * Initialize the client device
1242 */
1243 int fuse_dev_init(void);
1244
1245 /**
1246 * Cleanup the client device
1247 */
1248 void fuse_dev_cleanup(void);
1249
1250 int fuse_ctl_init(void);
1251 void __exit fuse_ctl_cleanup(void);
1252
1253 /**
1254 * Simple request sending that does request allocation and freeing
1255 */
1256 ssize_t __fuse_simple_request(struct mnt_idmap *idmap,
1257 struct fuse_mount *fm,
1258 struct fuse_args *args);
1259
fuse_simple_request(struct fuse_mount * fm,struct fuse_args * args)1260 static inline ssize_t fuse_simple_request(struct fuse_mount *fm, struct fuse_args *args)
1261 {
1262 return __fuse_simple_request(&invalid_mnt_idmap, fm, args);
1263 }
1264
fuse_simple_idmap_request(struct mnt_idmap * idmap,struct fuse_mount * fm,struct fuse_args * args)1265 static inline ssize_t fuse_simple_idmap_request(struct mnt_idmap *idmap,
1266 struct fuse_mount *fm,
1267 struct fuse_args *args)
1268 {
1269 return __fuse_simple_request(idmap, fm, args);
1270 }
1271
1272 int fuse_simple_background(struct fuse_mount *fm, struct fuse_args *args,
1273 gfp_t gfp_flags);
1274
1275 /**
1276 * Assign a unique id to a fuse request
1277 */
1278 void fuse_request_assign_unique(struct fuse_iqueue *fiq, struct fuse_req *req);
1279
1280 /**
1281 * End a finished request
1282 */
1283 void fuse_request_end(struct fuse_req *req);
1284
1285 /* Abort all requests */
1286 void fuse_abort_conn(struct fuse_conn *fc);
1287 void fuse_wait_aborted(struct fuse_conn *fc);
1288
1289 /* Check if any requests timed out */
1290 void fuse_check_timeout(struct work_struct *work);
1291
1292 void fuse_dentry_tree_init(void);
1293 void fuse_dentry_tree_cleanup(void);
1294
1295 void fuse_epoch_work(struct work_struct *work);
1296
1297 /**
1298 * Invalidate inode attributes
1299 */
1300
1301 /* Attributes possibly changed on data modification */
1302 #define FUSE_STATX_MODIFY (STATX_MTIME | STATX_CTIME | STATX_BLOCKS)
1303
1304 /* Attributes possibly changed on data and/or size modification */
1305 #define FUSE_STATX_MODSIZE (FUSE_STATX_MODIFY | STATX_SIZE)
1306
1307 void fuse_invalidate_attr(struct inode *inode);
1308 void fuse_invalidate_attr_mask(struct inode *inode, u32 mask);
1309
1310 void fuse_invalidate_entry_cache(struct dentry *entry);
1311
1312 void fuse_invalidate_atime(struct inode *inode);
1313
1314 u64 fuse_time_to_jiffies(u64 sec, u32 nsec);
1315 #define ATTR_TIMEOUT(o) \
1316 fuse_time_to_jiffies((o)->attr_valid, (o)->attr_valid_nsec)
1317
1318 void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o);
1319
1320 /**
1321 * Acquire reference to fuse_conn
1322 */
1323 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
1324
1325 /**
1326 * Initialize the fuse processing queue
1327 */
1328 void fuse_pqueue_init(struct fuse_pqueue *fpq);
1329
1330 /**
1331 * Initialize fuse_conn
1332 */
1333 void fuse_conn_init(struct fuse_conn *fc, struct fuse_mount *fm,
1334 struct user_namespace *user_ns,
1335 const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv);
1336
1337 /**
1338 * Release reference to fuse_conn
1339 */
1340 void fuse_conn_put(struct fuse_conn *fc);
1341
1342 struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc);
1343 struct fuse_dev *fuse_dev_alloc(void);
1344 void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc);
1345 void fuse_dev_put(struct fuse_dev *fud);
1346 int fuse_send_init(struct fuse_mount *fm);
1347
1348 /**
1349 * Fill in superblock and initialize fuse connection
1350 * @sb: partially-initialized superblock to fill in
1351 * @ctx: mount context
1352 */
1353 int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx);
1354
1355 /*
1356 * Remove the mount from the connection
1357 *
1358 * Returns whether this was the last mount
1359 */
1360 bool fuse_mount_remove(struct fuse_mount *fm);
1361
1362 /*
1363 * Setup context ops for submounts
1364 */
1365 int fuse_init_fs_context_submount(struct fs_context *fsc);
1366
1367 /*
1368 * Shut down the connection (possibly sending DESTROY request).
1369 */
1370 void fuse_conn_destroy(struct fuse_mount *fm);
1371
1372 /* Drop the connection and free the fuse mount */
1373 void fuse_mount_destroy(struct fuse_mount *fm);
1374
1375 /**
1376 * Add connection to control filesystem
1377 */
1378 int fuse_ctl_add_conn(struct fuse_conn *fc);
1379
1380 /**
1381 * Remove connection from control filesystem
1382 */
1383 void fuse_ctl_remove_conn(struct fuse_conn *fc);
1384
1385 /**
1386 * Is file type valid?
1387 */
1388 int fuse_valid_type(int m);
1389
1390 bool fuse_invalid_attr(struct fuse_attr *attr);
1391
1392 /**
1393 * Is current process allowed to perform filesystem operation?
1394 */
1395 bool fuse_allow_current_process(struct fuse_conn *fc);
1396
1397 u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
1398
1399 void fuse_flush_time_update(struct inode *inode);
1400 void fuse_update_ctime(struct inode *inode);
1401
1402 int fuse_update_attributes(struct inode *inode, struct file *file, u32 mask);
1403
1404 void fuse_flush_writepages(struct inode *inode);
1405
1406 void fuse_set_nowrite(struct inode *inode);
1407 void fuse_release_nowrite(struct inode *inode);
1408
1409 /**
1410 * Scan all fuse_mounts belonging to fc to find the first where
1411 * ilookup5() returns a result. Return that result and the
1412 * respective fuse_mount in *fm (unless fm is NULL).
1413 *
1414 * The caller must hold fc->killsb.
1415 */
1416 struct inode *fuse_ilookup(struct fuse_conn *fc, u64 nodeid,
1417 struct fuse_mount **fm);
1418
1419 /**
1420 * File-system tells the kernel to invalidate cache for the given node id.
1421 */
1422 int fuse_reverse_inval_inode(struct fuse_conn *fc, u64 nodeid,
1423 loff_t offset, loff_t len);
1424
1425 /**
1426 * File-system tells the kernel to invalidate parent attributes and
1427 * the dentry matching parent/name.
1428 *
1429 * If the child_nodeid is non-zero and:
1430 * - matches the inode number for the dentry matching parent/name,
1431 * - is not a mount point
1432 * - is a file or oan empty directory
1433 * then the dentry is unhashed (d_delete()).
1434 */
1435 int fuse_reverse_inval_entry(struct fuse_conn *fc, u64 parent_nodeid,
1436 u64 child_nodeid, struct qstr *name, u32 flags);
1437
1438 /*
1439 * Try to prune this inode. If neither the inode itself nor dentries associated
1440 * with this inode have any external reference, then the inode can be freed.
1441 */
1442 void fuse_try_prune_one_inode(struct fuse_conn *fc, u64 nodeid);
1443
1444 int fuse_do_open(struct fuse_mount *fm, u64 nodeid, struct file *file,
1445 bool isdir);
1446
1447 /**
1448 * fuse_direct_io() flags
1449 */
1450
1451 /** If set, it is WRITE; otherwise - READ */
1452 #define FUSE_DIO_WRITE (1 << 0)
1453
1454 /** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */
1455 #define FUSE_DIO_CUSE (1 << 1)
1456
1457 ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
1458 loff_t *ppos, int flags);
1459 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1460 unsigned int flags);
1461 long fuse_ioctl_common(struct file *file, unsigned int cmd,
1462 unsigned long arg, unsigned int flags);
1463 __poll_t fuse_file_poll(struct file *file, poll_table *wait);
1464 int fuse_dev_release(struct inode *inode, struct file *file);
1465
1466 bool fuse_write_update_attr(struct inode *inode, loff_t pos, ssize_t written);
1467
1468 int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
1469 int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
1470
1471 int fuse_do_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
1472 struct iattr *attr, struct file *file);
1473
1474 void fuse_set_initialized(struct fuse_conn *fc);
1475
1476 void fuse_unlock_inode(struct inode *inode, bool locked);
1477 bool fuse_lock_inode(struct inode *inode);
1478
1479 int fuse_setxattr(struct inode *inode, const char *name, const void *value,
1480 size_t size, int flags, unsigned int extra_flags);
1481 ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value,
1482 size_t size);
1483 ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size);
1484 int fuse_removexattr(struct inode *inode, const char *name);
1485 extern const struct xattr_handler * const fuse_xattr_handlers[];
1486
1487 struct posix_acl;
1488 struct posix_acl *fuse_get_inode_acl(struct inode *inode, int type, bool rcu);
1489 struct posix_acl *fuse_get_acl(struct mnt_idmap *idmap,
1490 struct dentry *dentry, int type);
1491 int fuse_set_acl(struct mnt_idmap *, struct dentry *dentry,
1492 struct posix_acl *acl, int type);
1493
1494 /* readdir.c */
1495 int fuse_readdir(struct file *file, struct dir_context *ctx);
1496
1497 /**
1498 * Return the number of bytes in an arguments list
1499 */
1500 unsigned int fuse_len_args(unsigned int numargs, struct fuse_arg *args);
1501
1502 /**
1503 * Get the next unique ID for a request
1504 */
1505 u64 fuse_get_unique(struct fuse_iqueue *fiq);
1506 void fuse_free_conn(struct fuse_conn *fc);
1507
1508 /* dax.c */
1509
1510 #define FUSE_IS_DAX(inode) (IS_ENABLED(CONFIG_FUSE_DAX) && IS_DAX(inode))
1511
1512 ssize_t fuse_dax_read_iter(struct kiocb *iocb, struct iov_iter *to);
1513 ssize_t fuse_dax_write_iter(struct kiocb *iocb, struct iov_iter *from);
1514 int fuse_dax_mmap(struct file *file, struct vm_area_struct *vma);
1515 int fuse_dax_break_layouts(struct inode *inode, u64 dmap_start, u64 dmap_end);
1516 int fuse_dax_conn_alloc(struct fuse_conn *fc, enum fuse_dax_mode mode,
1517 struct dax_device *dax_dev);
1518 void fuse_dax_conn_free(struct fuse_conn *fc);
1519 bool fuse_dax_inode_alloc(struct super_block *sb, struct fuse_inode *fi);
1520 void fuse_dax_inode_init(struct inode *inode, unsigned int flags);
1521 void fuse_dax_inode_cleanup(struct inode *inode);
1522 void fuse_dax_dontcache(struct inode *inode, unsigned int flags);
1523 bool fuse_dax_check_alignment(struct fuse_conn *fc, unsigned int map_alignment);
1524 void fuse_dax_cancel_work(struct fuse_conn *fc);
1525
1526 /* ioctl.c */
1527 long fuse_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1528 long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
1529 unsigned long arg);
1530 int fuse_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
1531 int fuse_fileattr_set(struct mnt_idmap *idmap,
1532 struct dentry *dentry, struct file_kattr *fa);
1533
1534 /* iomode.c */
1535 int fuse_file_cached_io_open(struct inode *inode, struct fuse_file *ff);
1536 int fuse_inode_uncached_io_start(struct fuse_inode *fi,
1537 struct fuse_backing *fb);
1538 void fuse_inode_uncached_io_end(struct fuse_inode *fi);
1539
1540 int fuse_file_io_open(struct file *file, struct inode *inode);
1541 void fuse_file_io_release(struct fuse_file *ff, struct inode *inode);
1542
1543 /* file.c */
1544 struct fuse_file *fuse_file_open(struct fuse_mount *fm, u64 nodeid,
1545 unsigned int open_flags, bool isdir);
1546 void fuse_file_release(struct inode *inode, struct fuse_file *ff,
1547 unsigned int open_flags, fl_owner_t id, bool isdir);
1548
1549 /* backing.c */
1550 #ifdef CONFIG_FUSE_PASSTHROUGH
1551 struct fuse_backing *fuse_backing_get(struct fuse_backing *fb);
1552 void fuse_backing_put(struct fuse_backing *fb);
1553 struct fuse_backing *fuse_backing_lookup(struct fuse_conn *fc, int backing_id);
1554 #else
1555
fuse_backing_get(struct fuse_backing * fb)1556 static inline struct fuse_backing *fuse_backing_get(struct fuse_backing *fb)
1557 {
1558 return NULL;
1559 }
1560
fuse_backing_put(struct fuse_backing * fb)1561 static inline void fuse_backing_put(struct fuse_backing *fb)
1562 {
1563 }
fuse_backing_lookup(struct fuse_conn * fc,int backing_id)1564 static inline struct fuse_backing *fuse_backing_lookup(struct fuse_conn *fc,
1565 int backing_id)
1566 {
1567 return NULL;
1568 }
1569 #endif
1570
1571 void fuse_backing_files_init(struct fuse_conn *fc);
1572 void fuse_backing_files_free(struct fuse_conn *fc);
1573 int fuse_backing_open(struct fuse_conn *fc, struct fuse_backing_map *map);
1574 int fuse_backing_close(struct fuse_conn *fc, int backing_id);
1575
1576 /* passthrough.c */
fuse_inode_backing(struct fuse_inode * fi)1577 static inline struct fuse_backing *fuse_inode_backing(struct fuse_inode *fi)
1578 {
1579 #ifdef CONFIG_FUSE_PASSTHROUGH
1580 return READ_ONCE(fi->fb);
1581 #else
1582 return NULL;
1583 #endif
1584 }
1585
fuse_inode_backing_set(struct fuse_inode * fi,struct fuse_backing * fb)1586 static inline struct fuse_backing *fuse_inode_backing_set(struct fuse_inode *fi,
1587 struct fuse_backing *fb)
1588 {
1589 #ifdef CONFIG_FUSE_PASSTHROUGH
1590 return xchg(&fi->fb, fb);
1591 #else
1592 return NULL;
1593 #endif
1594 }
1595
1596 struct fuse_backing *fuse_passthrough_open(struct file *file, int backing_id);
1597 void fuse_passthrough_release(struct fuse_file *ff, struct fuse_backing *fb);
1598
fuse_file_passthrough(struct fuse_file * ff)1599 static inline struct file *fuse_file_passthrough(struct fuse_file *ff)
1600 {
1601 #ifdef CONFIG_FUSE_PASSTHROUGH
1602 return ff->passthrough;
1603 #else
1604 return NULL;
1605 #endif
1606 }
1607
1608 ssize_t fuse_passthrough_read_iter(struct kiocb *iocb, struct iov_iter *iter);
1609 ssize_t fuse_passthrough_write_iter(struct kiocb *iocb, struct iov_iter *iter);
1610 ssize_t fuse_passthrough_splice_read(struct file *in, loff_t *ppos,
1611 struct pipe_inode_info *pipe,
1612 size_t len, unsigned int flags);
1613 ssize_t fuse_passthrough_splice_write(struct pipe_inode_info *pipe,
1614 struct file *out, loff_t *ppos,
1615 size_t len, unsigned int flags);
1616 ssize_t fuse_passthrough_mmap(struct file *file, struct vm_area_struct *vma);
1617
1618 #ifdef CONFIG_SYSCTL
1619 extern int fuse_sysctl_register(void);
1620 extern void fuse_sysctl_unregister(void);
1621 #else
1622 #define fuse_sysctl_register() (0)
1623 #define fuse_sysctl_unregister() do { } while (0)
1624 #endif /* CONFIG_SYSCTL */
1625
1626 #endif /* _FS_FUSE_I_H */
1627