fs/fuse/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 #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 /** Number of page pointers embedded in fuse_req */
  48 #define FUSE_REQ_INLINE_PAGES 1
  49
  50 /** List of active connections */
  51 extern struct list_head fuse_conn_list;
  52
  53 /** Global mutex protecting fuse_conn_list and the control filesystem */
  54 extern struct mutex fuse_mutex;
  55
  56 /** Module parameters */
  57 extern unsigned max_user_bgreq;
  58 extern unsigned max_user_congthresh;
  59
  60 /* One forget request */
  61 struct fuse_forget_link {
  62         struct fuse_forget_one forget_one;
  63         struct fuse_forget_link *next;
  64 };
  65
  66 /** FUSE inode */
  67 struct 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         /** The sticky bit in inode->i_mode may have been removed, so
  85             preserve the original mode */
  86         umode_t orig_i_mode;
  87
  88         /** 64 bit inode number */
  89         u64 orig_ino;
  90
  91         /** Version of last attribute change */
  92         u64 attr_version;
  93
  94         /** Files usable in writepage.  Protected by fc->lock */
  95         struct list_head write_files;
  96
  97         /** Writepages pending on truncate or fsync */
  98         struct list_head queued_writes;
  99
 100         /** Number of sent writes, a negative bias (FUSE_NOWRITE)
 101          * means more writes are blocked */
 102         int writectr;
 103
 104         /** Waitq for writepage completion */
 105         wait_queue_head_t page_waitq;
 106
 107         /** List of writepage requestst (pending or sent) */
 108         struct list_head writepages;
 109
 110         /** Miscellaneous bits describing inode state */
 111         unsigned long state;
 112 };
 113
 114 /** FUSE inode state bits */
 115 enum {
 116         /** Advise readdirplus  */
 117         FUSE_I_ADVISE_RDPLUS,
 118         /** An operation changing file size is in progress  */
 119         FUSE_I_SIZE_UNSTABLE,
 120 };
 121
 122 struct fuse_conn;
 123
 124 /** FUSE specific file data */
 125 struct fuse_file {
 126         /** Fuse connection for this file */
 127         struct fuse_conn *fc;
 128
 129         /** Request reserved for flush and release */
 130         struct fuse_req *reserved_req;
 131
 132         /** Kernel file handle guaranteed to be unique */
 133         u64 kh;
 134
 135         /** File handle used by userspace */
 136         u64 fh;
 137
 138         /** Node id of this file */
 139         u64 nodeid;
 140
 141         /** Refcount */
 142         atomic_t count;
 143
 144         /** FOPEN_* flags returned by open */
 145         u32 open_flags;
 146
 147         /** Entry on inode's write_files list */
 148         struct list_head write_entry;
 149
 150         /** RB node to be linked on fuse_conn->polled_files */
 151         struct rb_node polled_node;
 152
 153         /** Wait queue head for poll */
 154         wait_queue_head_t poll_wait;
 155
 156         /** Has flock been performed on this file? */
 157         bool flock:1;
 158 };
 159
 160 /** One input argument of a request */
 161 struct fuse_in_arg {
 162         unsigned size;
 163         const void *value;
 164 };
 165
 166 /** The request input */
 167 struct fuse_in {
 168         /** The request header */
 169         struct fuse_in_header h;
 170
 171         /** True if the data for the last argument is in req->pages */
 172         unsigned argpages:1;
 173
 174         /** Number of arguments */
 175         unsigned numargs;
 176
 177         /** Array of arguments */
 178         struct fuse_in_arg args[3];
 179 };
 180
 181 /** One output argument of a request */
 182 struct fuse_arg {
 183         unsigned size;
 184         void *value;
 185 };
 186
 187 /** The request output */
 188 struct fuse_out {
 189         /** Header returned from userspace */
 190         struct fuse_out_header h;
 191
 192         /*
 193          * The following bitfields are not changed during the request
 194          * processing
 195          */
 196
 197         /** Last argument is variable length (can be shorter than
 198             arg->size) */
 199         unsigned argvar:1;
 200
 201         /** Last argument is a list of pages to copy data to */
 202         unsigned argpages:1;
 203
 204         /** Zero partially or not copied pages */
 205         unsigned page_zeroing:1;
 206
 207         /** Pages may be replaced with new ones */
 208         unsigned page_replace:1;
 209
 210         /** Number or arguments */
 211         unsigned numargs;
 212
 213         /** Array of arguments */
 214         struct fuse_arg args[3];
 215 };
 216
 217 /** FUSE page descriptor */
 218 struct fuse_page_desc {
 219         unsigned int length;
 220         unsigned int offset;
 221 };
 222
 223 /** The request state */
 224 enum fuse_req_state {
 225         FUSE_REQ_INIT = 0,
 226         FUSE_REQ_PENDING,
 227         FUSE_REQ_READING,
 228         FUSE_REQ_SENT,
 229         FUSE_REQ_WRITING,
 230         FUSE_REQ_FINISHED
 231 };
 232
 233 /** The request IO state (for asynchronous processing) */
 234 struct fuse_io_priv {
 235         int async;
 236         spinlock_t lock;
 237         unsigned reqs;
 238         ssize_t bytes;
 239         size_t size;
 240         __u64 offset;
 241         bool write;
 242         int err;
 243         struct kiocb *iocb;
 244         struct file *file;
 245 };
 246
 247 /**
 248  * A request to the client
 249  */
 250 struct fuse_req {
 251         /** This can be on either pending processing or io lists in
 252             fuse_conn */
 253         struct list_head list;
 254
 255         /** Entry on the interrupts list  */
 256         struct list_head intr_entry;
 257
 258         /** refcount */
 259         atomic_t count;
 260
 261         /** Unique ID for the interrupt request */
 262         u64 intr_unique;
 263
 264         /*
 265          * The following bitfields are either set once before the
 266          * request is queued or setting/clearing them is protected by
 267          * fuse_conn->lock
 268          */
 269
 270         /** True if the request has reply */
 271         unsigned isreply:1;
 272
 273         /** Force sending of the request even if interrupted */
 274         unsigned force:1;
 275
 276         /** The request was aborted */
 277         unsigned aborted:1;
 278
 279         /** Request is sent in the background */
 280         unsigned background:1;
 281
 282         /** The request has been interrupted */
 283         unsigned interrupted:1;
 284
 285         /** Data is being copied to/from the request */
 286         unsigned locked:1;
 287
 288         /** Request is counted as "waiting" */
 289         unsigned waiting:1;
 290
 291         /** State of the request */
 292         enum fuse_req_state state;
 293
 294         /** The request input */
 295         struct fuse_in in;
 296
 297         /** The request output */
 298         struct fuse_out out;
 299
 300         /** Used to wake up the task waiting for completion of request*/
 301         wait_queue_head_t waitq;
 302
 303         /** Data for asynchronous requests */
 304         union {
 305                 struct {
 306                         union {
 307                                 struct fuse_release_in in;
 308                                 struct work_struct work;
 309                         };
 310                         struct path path;
 311                 } release;
 312                 struct fuse_init_in init_in;
 313                 struct fuse_init_out init_out;
 314                 struct cuse_init_in cuse_init_in;
 315                 struct {
 316                         struct fuse_read_in in;
 317                         u64 attr_ver;
 318                 } read;
 319                 struct {
 320                         struct fuse_write_in in;
 321                         struct fuse_write_out out;
 322                 } write;
 323                 struct fuse_notify_retrieve_in retrieve_in;
 324                 struct fuse_lk_in lk_in;
 325         } misc;
 326
 327         /** page vector */
 328         struct page **pages;
 329
 330         /** page-descriptor vector */
 331         struct fuse_page_desc *page_descs;
 332
 333         /** size of the 'pages' array */
 334         unsigned max_pages;
 335
 336         /** inline page vector */
 337         struct page *inline_pages[FUSE_REQ_INLINE_PAGES];
 338
 339         /** inline page-descriptor vector */
 340         struct fuse_page_desc inline_page_descs[FUSE_REQ_INLINE_PAGES];
 341
 342         /** number of pages in vector */
 343         unsigned num_pages;
 344
 345         /** File used in the request (or NULL) */
 346         struct fuse_file *ff;
 347
 348         /** Inode used in the request or NULL */
 349         struct inode *inode;
 350
 351         /** AIO control block */
 352         struct fuse_io_priv *io;
 353
 354         /** Link on fi->writepages */
 355         struct list_head writepages_entry;
 356
 357         /** Request completion callback */
 358         void (*end)(struct fuse_conn *, struct fuse_req *);
 359
 360         /** Request is stolen from fuse_file->reserved_req */
 361         struct file *stolen_file;
 362 };
 363
 364 /**
 365  * A Fuse connection.
 366  *
 367  * This structure is created, when the filesystem is mounted, and is
 368  * destroyed, when the client device is closed and the filesystem is
 369  * unmounted.
 370  */
 371 struct fuse_conn {
 372         /** Lock protecting accessess to  members of this structure */
 373         spinlock_t lock;
 374
 375         /** Mutex protecting against directory alias creation */
 376         struct mutex inst_mutex;
 377
 378         /** Refcount */
 379         atomic_t count;
 380
 381         /** The user id for this mount */
 382         kuid_t user_id;
 383
 384         /** The group id for this mount */
 385         kgid_t group_id;
 386
 387         /** The fuse mount flags for this mount */
 388         unsigned flags;
 389
 390         /** Maximum read size */
 391         unsigned max_read;
 392
 393         /** Maximum write size */
 394         unsigned max_write;
 395
 396         /** Readers of the connection are waiting on this */
 397         wait_queue_head_t waitq;
 398
 399         /** The list of pending requests */
 400         struct list_head pending;
 401
 402         /** The list of requests being processed */
 403         struct list_head processing;
 404
 405         /** The list of requests under I/O */
 406         struct list_head io;
 407
 408         /** The next unique kernel file handle */
 409         u64 khctr;
 410
 411         /** rbtree of fuse_files waiting for poll events indexed by ph */
 412         struct rb_root polled_files;
 413
 414         /** Maximum number of outstanding background requests */
 415         unsigned max_background;
 416
 417         /** Number of background requests at which congestion starts */
 418         unsigned congestion_threshold;
 419
 420         /** Number of requests currently in the background */
 421         unsigned num_background;
 422
 423         /** Number of background requests currently queued for userspace */
 424         unsigned active_background;
 425
 426         /** The list of background requests set aside for later queuing */
 427         struct list_head bg_queue;
 428
 429         /** Pending interrupts */
 430         struct list_head interrupts;
 431
 432         /** Queue of pending forgets */
 433         struct fuse_forget_link forget_list_head;
 434         struct fuse_forget_link *forget_list_tail;
 435
 436         /** Batching of FORGET requests (positive indicates FORGET batch) */
 437         int forget_batch;
 438
 439         /** Flag indicating that INIT reply has been received. Allocating
 440          * any fuse request will be suspended until the flag is set */
 441         int initialized;
 442
 443         /** Flag indicating if connection is blocked.  This will be
 444             the case before the INIT reply is received, and if there
 445             are too many outstading backgrounds requests */
 446         int blocked;
 447
 448         /** waitq for blocked connection */
 449         wait_queue_head_t blocked_waitq;
 450
 451         /** waitq for reserved requests */
 452         wait_queue_head_t reserved_req_waitq;
 453
 454         /** The next unique request id */
 455         u64 reqctr;
 456
 457         /** Connection established, cleared on umount, connection
 458             abort and device release */
 459         unsigned connected;
 460
 461         /** Connection failed (version mismatch).  Cannot race with
 462             setting other bitfields since it is only set once in INIT
 463             reply, before any other request, and never cleared */
 464         unsigned conn_error:1;
 465
 466         /** Connection successful.  Only set in INIT */
 467         unsigned conn_init:1;
 468
 469         /** Do readpages asynchronously?  Only set in INIT */
 470         unsigned async_read:1;
 471
 472         /** Do not send separate SETATTR request before open(O_TRUNC)  */
 473         unsigned atomic_o_trunc:1;
 474
 475         /** Filesystem supports NFS exporting.  Only set in INIT */
 476         unsigned export_support:1;
 477
 478         /** Set if bdi is valid */
 479         unsigned bdi_initialized:1;
 480
 481         /*
 482          * The following bitfields are only for optimization purposes
 483          * and hence races in setting them will not cause malfunction
 484          */
 485
 486         /** Is fsync not implemented by fs? */
 487         unsigned no_fsync:1;
 488
 489         /** Is fsyncdir not implemented by fs? */
 490         unsigned no_fsyncdir:1;
 491
 492         /** Is flush not implemented by fs? */
 493         unsigned no_flush:1;
 494
 495         /** Is setxattr not implemented by fs? */
 496         unsigned no_setxattr:1;
 497
 498         /** Is getxattr not implemented by fs? */
 499         unsigned no_getxattr:1;
 500
 501         /** Is listxattr not implemented by fs? */
 502         unsigned no_listxattr:1;
 503
 504         /** Is removexattr not implemented by fs? */
 505         unsigned no_removexattr:1;
 506
 507         /** Are posix file locking primitives not implemented by fs? */
 508         unsigned no_lock:1;
 509
 510         /** Is access not implemented by fs? */
 511         unsigned no_access:1;
 512
 513         /** Is create not implemented by fs? */
 514         unsigned no_create:1;
 515
 516         /** Is interrupt not implemented by fs? */
 517         unsigned no_interrupt:1;
 518
 519         /** Is bmap not implemented by fs? */
 520         unsigned no_bmap:1;
 521
 522         /** Is poll not implemented by fs? */
 523         unsigned no_poll:1;
 524
 525         /** Do multi-page cached writes */
 526         unsigned big_writes:1;
 527
 528         /** Don't apply umask to creation modes */
 529         unsigned dont_mask:1;
 530
 531         /** Are BSD file locking primitives not implemented by fs? */
 532         unsigned no_flock:1;
 533
 534         /** Is fallocate not implemented by fs? */
 535         unsigned no_fallocate:1;
 536
 537         /** Use enhanced/automatic page cache invalidation. */
 538         unsigned auto_inval_data:1;
 539
 540         /** Does the filesystem support readdirplus? */
 541         unsigned do_readdirplus:1;
 542
 543         /** Does the filesystem want adaptive readdirplus? */
 544         unsigned readdirplus_auto:1;
 545
 546         /** Does the filesystem support asynchronous direct-IO submission? */
 547         unsigned async_dio:1;
 548
 549         /** The number of requests waiting for completion */
 550         atomic_t num_waiting;
 551
 552         /** Negotiated minor version */
 553         unsigned minor;
 554
 555         /** Backing dev info */
 556         struct backing_dev_info bdi;
 557
 558         /** Entry on the fuse_conn_list */
 559         struct list_head entry;
 560
 561         /** Device ID from super block */
 562         dev_t dev;
 563
 564         /** Dentries in the control filesystem */
 565         struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
 566
 567         /** number of dentries used in the above array */
 568         int ctl_ndents;
 569
 570         /** O_ASYNC requests */
 571         struct fasync_struct *fasync;
 572
 573         /** Key for lock owner ID scrambling */
 574         u32 scramble_key[4];
 575
 576         /** Reserved request for the DESTROY message */
 577         struct fuse_req *destroy_req;
 578
 579         /** Version counter for attribute changes */
 580         u64 attr_version;
 581
 582         /** Called on final put */
 583         void (*release)(struct fuse_conn *);
 584
 585         /** Super block for this connection. */
 586         struct super_block *sb;
 587
 588         /** Read/write semaphore to hold when accessing sb. */
 589         struct rw_semaphore killsb;
 590 };
 591
 592 static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
 593 {
 594         return sb->s_fs_info;
 595 }
 596
 597 static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
 598 {
 599         return get_fuse_conn_super(inode->i_sb);
 600 }
 601
 602 static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
 603 {
 604         return container_of(inode, struct fuse_inode, inode);
 605 }
 606
 607 static inline u64 get_node_id(struct inode *inode)
 608 {
 609         return get_fuse_inode(inode)->nodeid;
 610 }
 611
 612 /** Device operations */
 613 extern const struct file_operations fuse_dev_operations;
 614
 615 extern const struct dentry_operations fuse_dentry_operations;
 616
 617 /**
 618  * Inode to nodeid comparison.
 619  */
 620 int fuse_inode_eq(struct inode *inode, void *_nodeidp);
 621
 622 /**
 623  * Get a filled in inode
 624  */
 625 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
 626                         int generation, struct fuse_attr *attr,
 627                         u64 attr_valid, u64 attr_version);
 628
 629 int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
 630                      struct fuse_entry_out *outarg, struct inode **inode);
 631
 632 /**
 633  * Send FORGET command
 634  */
 635 void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
 636                        u64 nodeid, u64 nlookup);
 637
 638 struct fuse_forget_link *fuse_alloc_forget(void);
 639
 640 /* Used by READDIRPLUS */
 641 void fuse_force_forget(struct file *file, u64 nodeid);
 642
 643 /**
 644  * Initialize READ or READDIR request
 645  */
 646 void fuse_read_fill(struct fuse_req *req, struct file *file,
 647                     loff_t pos, size_t count, int opcode);
 648
 649 /**
 650  * Send OPEN or OPENDIR request
 651  */
 652 int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
 653
 654 struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
 655 struct fuse_file *fuse_file_get(struct fuse_file *ff);
 656 void fuse_file_free(struct fuse_file *ff);
 657 void fuse_finish_open(struct inode *inode, struct file *file);
 658
 659 void fuse_sync_release(struct fuse_file *ff, int flags);
 660
 661 /**
 662  * Send RELEASE or RELEASEDIR request
 663  */
 664 void fuse_release_common(struct file *file, int opcode);
 665
 666 /**
 667  * Send FSYNC or FSYNCDIR request
 668  */
 669 int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
 670                       int datasync, int isdir);
 671
 672 /**
 673  * Notify poll wakeup
 674  */
 675 int fuse_notify_poll_wakeup(struct fuse_conn *fc,
 676                             struct fuse_notify_poll_wakeup_out *outarg);
 677
 678 /**
 679  * Initialize file operations on a regular file
 680  */
 681 void fuse_init_file_inode(struct inode *inode);
 682
 683 /**
 684  * Initialize inode operations on regular files and special files
 685  */
 686 void fuse_init_common(struct inode *inode);
 687
 688 /**
 689  * Initialize inode and file operations on a directory
 690  */
 691 void fuse_init_dir(struct inode *inode);
 692
 693 /**
 694  * Initialize inode operations on a symlink
 695  */
 696 void fuse_init_symlink(struct inode *inode);
 697
 698 /**
 699  * Change attributes of an inode
 700  */
 701 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 702                             u64 attr_valid, u64 attr_version);
 703
 704 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
 705                                    u64 attr_valid);
 706
 707 /**
 708  * Initialize the client device
 709  */
 710 int fuse_dev_init(void);
 711
 712 /**
 713  * Cleanup the client device
 714  */
 715 void fuse_dev_cleanup(void);
 716
 717 int fuse_ctl_init(void);
 718 void fuse_ctl_cleanup(void);
 719
 720 /**
 721  * Allocate a request
 722  */
 723 struct fuse_req *fuse_request_alloc(unsigned npages);
 724
 725 struct fuse_req *fuse_request_alloc_nofs(unsigned npages);
 726
 727 /**
 728  * Free a request
 729  */
 730 void fuse_request_free(struct fuse_req *req);
 731
 732 /**
 733  * Get a request, may fail with -ENOMEM,
 734  * caller should specify # elements in req->pages[] explicitly
 735  */
 736 struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages);
 737 struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
 738                                              unsigned npages);
 739
 740 /*
 741  * Increment reference count on request
 742  */
 743 void __fuse_get_request(struct fuse_req *req);
 744
 745 /**
 746  * Get a request, may fail with -ENOMEM,
 747  * useful for callers who doesn't use req->pages[]
 748  */
 749 static inline struct fuse_req *fuse_get_req_nopages(struct fuse_conn *fc)
 750 {
 751         return fuse_get_req(fc, 0);
 752 }
 753
 754 /**
 755  * Gets a requests for a file operation, always succeeds
 756  */
 757 struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
 758                                              struct file *file);
 759
 760 /**
 761  * Decrement reference count of a request.  If count goes to zero free
 762  * the request.
 763  */
 764 void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
 765
 766 /**
 767  * Send a request (synchronous)
 768  */
 769 void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);
 770
 771 /**
 772  * Send a request in the background
 773  */
 774 void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req);
 775
 776 void fuse_request_send_background_locked(struct fuse_conn *fc,
 777                                          struct fuse_req *req);
 778
 779 /* Abort all requests */
 780 void fuse_abort_conn(struct fuse_conn *fc);
 781
 782 /**
 783  * Invalidate inode attributes
 784  */
 785 void fuse_invalidate_attr(struct inode *inode);
 786
 787 void fuse_invalidate_entry_cache(struct dentry *entry);
 788
 789 /**
 790  * Acquire reference to fuse_conn
 791  */
 792 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
 793
 794 void fuse_conn_kill(struct fuse_conn *fc);
 795
 796 /**
 797  * Initialize fuse_conn
 798  */
 799 void fuse_conn_init(struct fuse_conn *fc);
 800
 801 /**
 802  * Release reference to fuse_conn
 803  */
 804 void fuse_conn_put(struct fuse_conn *fc);
 805
 806 /**
 807  * Add connection to control filesystem
 808  */
 809 int fuse_ctl_add_conn(struct fuse_conn *fc);
 810
 811 /**
 812  * Remove connection from control filesystem
 813  */
 814 void fuse_ctl_remove_conn(struct fuse_conn *fc);
 815
 816 /**
 817  * Is file type valid?
 818  */
 819 int fuse_valid_type(int m);
 820
 821 /**
 822  * Is current process allowed to perform filesystem operation?
 823  */
 824 int fuse_allow_current_process(struct fuse_conn *fc);
 825
 826 u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
 827
 828 int fuse_update_attributes(struct inode *inode, struct kstat *stat,
 829                            struct file *file, bool *refreshed);
 830
 831 void fuse_flush_writepages(struct inode *inode);
 832
 833 void fuse_set_nowrite(struct inode *inode);
 834 void fuse_release_nowrite(struct inode *inode);
 835
 836 u64 fuse_get_attr_version(struct fuse_conn *fc);
 837
 838 /**
 839  * File-system tells the kernel to invalidate cache for the given node id.
 840  */
 841 int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
 842                              loff_t offset, loff_t len);
 843
 844 /**
 845  * File-system tells the kernel to invalidate parent attributes and
 846  * the dentry matching parent/name.
 847  *
 848  * If the child_nodeid is non-zero and:
 849  *    - matches the inode number for the dentry matching parent/name,
 850  *    - is not a mount point
 851  *    - is a file or oan empty directory
 852  * then the dentry is unhashed (d_delete()).
 853  */
 854 int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
 855                              u64 child_nodeid, struct qstr *name);
 856
 857 int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
 858                  bool isdir);
 859 ssize_t fuse_direct_io(struct fuse_io_priv *io, const struct iovec *iov,
 860                        unsigned long nr_segs, size_t count, loff_t *ppos,
 861                        int write);
 862 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
 863                    unsigned int flags);
 864 long fuse_ioctl_common(struct file *file, unsigned int cmd,
 865                        unsigned long arg, unsigned int flags);
 866 unsigned fuse_file_poll(struct file *file, poll_table *wait);
 867 int fuse_dev_release(struct inode *inode, struct file *file);
 868
 869 void fuse_write_update_size(struct inode *inode, loff_t pos);
 870
 871 int fuse_do_setattr(struct inode *inode, struct iattr *attr,
 872                     struct file *file);
 873
 874 #endif /* _FS_FUSE_I_H */