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         /** Initialized with readdirplus */
 119         FUSE_I_INIT_RDPLUS,
 120         /** An operation changing file size is in progress  */
 121         FUSE_I_SIZE_UNSTABLE,
 122 };
 123
 124 struct fuse_conn;
 125
 126 /** FUSE specific file data */
 127 struct fuse_file {
 128         /** Fuse connection for this file */
 129         struct fuse_conn *fc;
 130
 131         /** Request reserved for flush and release */
 132         struct fuse_req *reserved_req;
 133
 134         /** Kernel file handle guaranteed to be unique */
 135         u64 kh;
 136
 137         /** File handle used by userspace */
 138         u64 fh;
 139
 140         /** Node id of this file */
 141         u64 nodeid;
 142
 143         /** Refcount */
 144         atomic_t count;
 145
 146         /** FOPEN_* flags returned by open */
 147         u32 open_flags;
 148
 149         /** Entry on inode's write_files list */
 150         struct list_head write_entry;
 151
 152         /** RB node to be linked on fuse_conn->polled_files */
 153         struct rb_node polled_node;
 154
 155         /** Wait queue head for poll */
 156         wait_queue_head_t poll_wait;
 157
 158         /** Has flock been performed on this file? */
 159         bool flock:1;
 160 };
 161
 162 /** One input argument of a request */
 163 struct fuse_in_arg {
 164         unsigned size;
 165         const void *value;
 166 };
 167
 168 /** The request input */
 169 struct fuse_in {
 170         /** The request header */
 171         struct fuse_in_header h;
 172
 173         /** True if the data for the last argument is in req->pages */
 174         unsigned argpages:1;
 175
 176         /** Number of arguments */
 177         unsigned numargs;
 178
 179         /** Array of arguments */
 180         struct fuse_in_arg args[3];
 181 };
 182
 183 /** One output argument of a request */
 184 struct fuse_arg {
 185         unsigned size;
 186         void *value;
 187 };
 188
 189 /** The request output */
 190 struct fuse_out {
 191         /** Header returned from userspace */
 192         struct fuse_out_header h;
 193
 194         /*
 195          * The following bitfields are not changed during the request
 196          * processing
 197          */
 198
 199         /** Last argument is variable length (can be shorter than
 200             arg->size) */
 201         unsigned argvar:1;
 202
 203         /** Last argument is a list of pages to copy data to */
 204         unsigned argpages:1;
 205
 206         /** Zero partially or not copied pages */
 207         unsigned page_zeroing:1;
 208
 209         /** Pages may be replaced with new ones */
 210         unsigned page_replace:1;
 211
 212         /** Number or arguments */
 213         unsigned numargs;
 214
 215         /** Array of arguments */
 216         struct fuse_arg args[2];
 217 };
 218
 219 /** FUSE page descriptor */
 220 struct fuse_page_desc {
 221         unsigned int length;
 222         unsigned int offset;
 223 };
 224
 225 struct fuse_args {
 226         struct {
 227                 struct {
 228                         uint32_t opcode;
 229                         uint64_t nodeid;
 230                 } h;
 231                 unsigned numargs;
 232                 struct fuse_in_arg args[3];
 233
 234         } in;
 235         struct {
 236                 unsigned argvar:1;
 237                 unsigned numargs;
 238                 struct fuse_arg args[2];
 239         } out;
 240 };
 241
 242 #define FUSE_ARGS(args) struct fuse_args args = {}
 243
 244 /** The request state */
 245 enum fuse_req_state {
 246         FUSE_REQ_INIT = 0,
 247         FUSE_REQ_PENDING,
 248         FUSE_REQ_READING,
 249         FUSE_REQ_SENT,
 250         FUSE_REQ_WRITING,
 251         FUSE_REQ_FINISHED
 252 };
 253
 254 /** The request IO state (for asynchronous processing) */
 255 struct fuse_io_priv {
 256         int async;
 257         spinlock_t lock;
 258         unsigned reqs;
 259         ssize_t bytes;
 260         size_t size;
 261         __u64 offset;
 262         bool write;
 263         int err;
 264         struct kiocb *iocb;
 265         struct file *file;
 266 };
 267
 268 /**
 269  * A request to the client
 270  */
 271 struct fuse_req {
 272         /** This can be on either pending processing or io lists in
 273             fuse_conn */
 274         struct list_head list;
 275
 276         /** Entry on the interrupts list  */
 277         struct list_head intr_entry;
 278
 279         /** refcount */
 280         atomic_t count;
 281
 282         /** Unique ID for the interrupt request */
 283         u64 intr_unique;
 284
 285         /*
 286          * The following bitfields are either set once before the
 287          * request is queued or setting/clearing them is protected by
 288          * fuse_conn->lock
 289          */
 290
 291         /** True if the request has reply */
 292         unsigned isreply:1;
 293
 294         /** Force sending of the request even if interrupted */
 295         unsigned force:1;
 296
 297         /** The request was aborted */
 298         unsigned aborted:1;
 299
 300         /** Request is sent in the background */
 301         unsigned background:1;
 302
 303         /** The request has been interrupted */
 304         unsigned interrupted:1;
 305
 306         /** Data is being copied to/from the request */
 307         unsigned locked:1;
 308
 309         /** Request is counted as "waiting" */
 310         unsigned waiting:1;
 311
 312         /** State of the request */
 313         enum fuse_req_state state;
 314
 315         /** The request input */
 316         struct fuse_in in;
 317
 318         /** The request output */
 319         struct fuse_out out;
 320
 321         /** Used to wake up the task waiting for completion of request*/
 322         wait_queue_head_t waitq;
 323
 324         /** Data for asynchronous requests */
 325         union {
 326                 struct {
 327                         struct fuse_release_in in;
 328                         struct inode *inode;
 329                 } release;
 330                 struct fuse_init_in init_in;
 331                 struct fuse_init_out init_out;
 332                 struct cuse_init_in cuse_init_in;
 333                 struct {
 334                         struct fuse_read_in in;
 335                         u64 attr_ver;
 336                 } read;
 337                 struct {
 338                         struct fuse_write_in in;
 339                         struct fuse_write_out out;
 340                         struct fuse_req *next;
 341                 } write;
 342                 struct fuse_notify_retrieve_in retrieve_in;
 343         } misc;
 344
 345         /** page vector */
 346         struct page **pages;
 347
 348         /** page-descriptor vector */
 349         struct fuse_page_desc *page_descs;
 350
 351         /** size of the 'pages' array */
 352         unsigned max_pages;
 353
 354         /** inline page vector */
 355         struct page *inline_pages[FUSE_REQ_INLINE_PAGES];
 356
 357         /** inline page-descriptor vector */
 358         struct fuse_page_desc inline_page_descs[FUSE_REQ_INLINE_PAGES];
 359
 360         /** number of pages in vector */
 361         unsigned num_pages;
 362
 363         /** File used in the request (or NULL) */
 364         struct fuse_file *ff;
 365
 366         /** Inode used in the request or NULL */
 367         struct inode *inode;
 368
 369         /** AIO control block */
 370         struct fuse_io_priv *io;
 371
 372         /** Link on fi->writepages */
 373         struct list_head writepages_entry;
 374
 375         /** Request completion callback */
 376         void (*end)(struct fuse_conn *, struct fuse_req *);
 377
 378         /** Request is stolen from fuse_file->reserved_req */
 379         struct file *stolen_file;
 380 };
 381
 382 /**
 383  * A Fuse connection.
 384  *
 385  * This structure is created, when the filesystem is mounted, and is
 386  * destroyed, when the client device is closed and the filesystem is
 387  * unmounted.
 388  */
 389 struct fuse_conn {
 390         /** Lock protecting accessess to  members of this structure */
 391         spinlock_t lock;
 392
 393         /** Refcount */
 394         atomic_t count;
 395
 396         struct rcu_head rcu;
 397
 398         /** The user id for this mount */
 399         kuid_t user_id;
 400
 401         /** The group id for this mount */
 402         kgid_t group_id;
 403
 404         /** The fuse mount flags for this mount */
 405         unsigned flags;
 406
 407         /** Maximum read size */
 408         unsigned max_read;
 409
 410         /** Maximum write size */
 411         unsigned max_write;
 412
 413         /** Readers of the connection are waiting on this */
 414         wait_queue_head_t waitq;
 415
 416         /** The list of pending requests */
 417         struct list_head pending;
 418
 419         /** The list of requests being processed */
 420         struct list_head processing;
 421
 422         /** The list of requests under I/O */
 423         struct list_head io;
 424
 425         /** The next unique kernel file handle */
 426         u64 khctr;
 427
 428         /** rbtree of fuse_files waiting for poll events indexed by ph */
 429         struct rb_root polled_files;
 430
 431         /** Maximum number of outstanding background requests */
 432         unsigned max_background;
 433
 434         /** Number of background requests at which congestion starts */
 435         unsigned congestion_threshold;
 436
 437         /** Number of requests currently in the background */
 438         unsigned num_background;
 439
 440         /** Number of background requests currently queued for userspace */
 441         unsigned active_background;
 442
 443         /** The list of background requests set aside for later queuing */
 444         struct list_head bg_queue;
 445
 446         /** Pending interrupts */
 447         struct list_head interrupts;
 448
 449         /** Queue of pending forgets */
 450         struct fuse_forget_link forget_list_head;
 451         struct fuse_forget_link *forget_list_tail;
 452
 453         /** Batching of FORGET requests (positive indicates FORGET batch) */
 454         int forget_batch;
 455
 456         /** Flag indicating that INIT reply has been received. Allocating
 457          * any fuse request will be suspended until the flag is set */
 458         int initialized;
 459
 460         /** Flag indicating if connection is blocked.  This will be
 461             the case before the INIT reply is received, and if there
 462             are too many outstading backgrounds requests */
 463         int blocked;
 464
 465         /** waitq for blocked connection */
 466         wait_queue_head_t blocked_waitq;
 467
 468         /** waitq for reserved requests */
 469         wait_queue_head_t reserved_req_waitq;
 470
 471         /** The next unique request id */
 472         u64 reqctr;
 473
 474         /** Connection established, cleared on umount, connection
 475             abort and device release */
 476         unsigned connected;
 477
 478         /** Connection failed (version mismatch).  Cannot race with
 479             setting other bitfields since it is only set once in INIT
 480             reply, before any other request, and never cleared */
 481         unsigned conn_error:1;
 482
 483         /** Connection successful.  Only set in INIT */
 484         unsigned conn_init:1;
 485
 486         /** Do readpages asynchronously?  Only set in INIT */
 487         unsigned async_read:1;
 488
 489         /** Do not send separate SETATTR request before open(O_TRUNC)  */
 490         unsigned atomic_o_trunc:1;
 491
 492         /** Filesystem supports NFS exporting.  Only set in INIT */
 493         unsigned export_support:1;
 494
 495         /** Set if bdi is valid */
 496         unsigned bdi_initialized:1;
 497
 498         /** write-back cache policy (default is write-through) */
 499         unsigned writeback_cache:1;
 500
 501         /*
 502          * The following bitfields are only for optimization purposes
 503          * and hence races in setting them will not cause malfunction
 504          */
 505
 506         /** Is open/release not implemented by fs? */
 507         unsigned no_open:1;
 508
 509         /** Is fsync not implemented by fs? */
 510         unsigned no_fsync:1;
 511
 512         /** Is fsyncdir not implemented by fs? */
 513         unsigned no_fsyncdir:1;
 514
 515         /** Is flush not implemented by fs? */
 516         unsigned no_flush:1;
 517
 518         /** Is setxattr not implemented by fs? */
 519         unsigned no_setxattr:1;
 520
 521         /** Is getxattr not implemented by fs? */
 522         unsigned no_getxattr:1;
 523
 524         /** Is listxattr not implemented by fs? */
 525         unsigned no_listxattr:1;
 526
 527         /** Is removexattr not implemented by fs? */
 528         unsigned no_removexattr:1;
 529
 530         /** Are posix file locking primitives not implemented by fs? */
 531         unsigned no_lock:1;
 532
 533         /** Is access not implemented by fs? */
 534         unsigned no_access:1;
 535
 536         /** Is create not implemented by fs? */
 537         unsigned no_create:1;
 538
 539         /** Is interrupt not implemented by fs? */
 540         unsigned no_interrupt:1;
 541
 542         /** Is bmap not implemented by fs? */
 543         unsigned no_bmap:1;
 544
 545         /** Is poll not implemented by fs? */
 546         unsigned no_poll:1;
 547
 548         /** Do multi-page cached writes */
 549         unsigned big_writes:1;
 550
 551         /** Don't apply umask to creation modes */
 552         unsigned dont_mask:1;
 553
 554         /** Are BSD file locking primitives not implemented by fs? */
 555         unsigned no_flock:1;
 556
 557         /** Is fallocate not implemented by fs? */
 558         unsigned no_fallocate:1;
 559
 560         /** Is rename with flags implemented by fs? */
 561         unsigned no_rename2:1;
 562
 563         /** Use enhanced/automatic page cache invalidation. */
 564         unsigned auto_inval_data:1;
 565
 566         /** Does the filesystem support readdirplus? */
 567         unsigned do_readdirplus:1;
 568
 569         /** Does the filesystem want adaptive readdirplus? */
 570         unsigned readdirplus_auto:1;
 571
 572         /** Does the filesystem support asynchronous direct-IO submission? */
 573         unsigned async_dio:1;
 574
 575         /** The number of requests waiting for completion */
 576         atomic_t num_waiting;
 577
 578         /** Negotiated minor version */
 579         unsigned minor;
 580
 581         /** Backing dev info */
 582         struct backing_dev_info bdi;
 583
 584         /** Entry on the fuse_conn_list */
 585         struct list_head entry;
 586
 587         /** Device ID from super block */
 588         dev_t dev;
 589
 590         /** Dentries in the control filesystem */
 591         struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES];
 592
 593         /** number of dentries used in the above array */
 594         int ctl_ndents;
 595
 596         /** O_ASYNC requests */
 597         struct fasync_struct *fasync;
 598
 599         /** Key for lock owner ID scrambling */
 600         u32 scramble_key[4];
 601
 602         /** Reserved request for the DESTROY message */
 603         struct fuse_req *destroy_req;
 604
 605         /** Version counter for attribute changes */
 606         u64 attr_version;
 607
 608         /** Called on final put */
 609         void (*release)(struct fuse_conn *);
 610
 611         /** Super block for this connection. */
 612         struct super_block *sb;
 613
 614         /** Read/write semaphore to hold when accessing sb. */
 615         struct rw_semaphore killsb;
 616 };
 617
 618 static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb)
 619 {
 620         return sb->s_fs_info;
 621 }
 622
 623 static inline struct fuse_conn *get_fuse_conn(struct inode *inode)
 624 {
 625         return get_fuse_conn_super(inode->i_sb);
 626 }
 627
 628 static inline struct fuse_inode *get_fuse_inode(struct inode *inode)
 629 {
 630         return container_of(inode, struct fuse_inode, inode);
 631 }
 632
 633 static inline u64 get_node_id(struct inode *inode)
 634 {
 635         return get_fuse_inode(inode)->nodeid;
 636 }
 637
 638 /** Device operations */
 639 extern const struct file_operations fuse_dev_operations;
 640
 641 extern const struct dentry_operations fuse_dentry_operations;
 642
 643 /**
 644  * Inode to nodeid comparison.
 645  */
 646 int fuse_inode_eq(struct inode *inode, void *_nodeidp);
 647
 648 /**
 649  * Get a filled in inode
 650  */
 651 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
 652                         int generation, struct fuse_attr *attr,
 653                         u64 attr_valid, u64 attr_version);
 654
 655 int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
 656                      struct fuse_entry_out *outarg, struct inode **inode);
 657
 658 /**
 659  * Send FORGET command
 660  */
 661 void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
 662                        u64 nodeid, u64 nlookup);
 663
 664 struct fuse_forget_link *fuse_alloc_forget(void);
 665
 666 /* Used by READDIRPLUS */
 667 void fuse_force_forget(struct file *file, u64 nodeid);
 668
 669 /**
 670  * Initialize READ or READDIR request
 671  */
 672 void fuse_read_fill(struct fuse_req *req, struct file *file,
 673                     loff_t pos, size_t count, int opcode);
 674
 675 /**
 676  * Send OPEN or OPENDIR request
 677  */
 678 int fuse_open_common(struct inode *inode, struct file *file, bool isdir);
 679
 680 struct fuse_file *fuse_file_alloc(struct fuse_conn *fc);
 681 struct fuse_file *fuse_file_get(struct fuse_file *ff);
 682 void fuse_file_free(struct fuse_file *ff);
 683 void fuse_finish_open(struct inode *inode, struct file *file);
 684
 685 void fuse_sync_release(struct fuse_file *ff, int flags);
 686
 687 /**
 688  * Send RELEASE or RELEASEDIR request
 689  */
 690 void fuse_release_common(struct file *file, int opcode);
 691
 692 /**
 693  * Send FSYNC or FSYNCDIR request
 694  */
 695 int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
 696                       int datasync, int isdir);
 697
 698 /**
 699  * Notify poll wakeup
 700  */
 701 int fuse_notify_poll_wakeup(struct fuse_conn *fc,
 702                             struct fuse_notify_poll_wakeup_out *outarg);
 703
 704 /**
 705  * Initialize file operations on a regular file
 706  */
 707 void fuse_init_file_inode(struct inode *inode);
 708
 709 /**
 710  * Initialize inode operations on regular files and special files
 711  */
 712 void fuse_init_common(struct inode *inode);
 713
 714 /**
 715  * Initialize inode and file operations on a directory
 716  */
 717 void fuse_init_dir(struct inode *inode);
 718
 719 /**
 720  * Initialize inode operations on a symlink
 721  */
 722 void fuse_init_symlink(struct inode *inode);
 723
 724 /**
 725  * Change attributes of an inode
 726  */
 727 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 728                             u64 attr_valid, u64 attr_version);
 729
 730 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
 731                                    u64 attr_valid);
 732
 733 /**
 734  * Initialize the client device
 735  */
 736 int fuse_dev_init(void);
 737
 738 /**
 739  * Cleanup the client device
 740  */
 741 void fuse_dev_cleanup(void);
 742
 743 int fuse_ctl_init(void);
 744 void __exit fuse_ctl_cleanup(void);
 745
 746 /**
 747  * Allocate a request
 748  */
 749 struct fuse_req *fuse_request_alloc(unsigned npages);
 750
 751 struct fuse_req *fuse_request_alloc_nofs(unsigned npages);
 752
 753 /**
 754  * Free a request
 755  */
 756 void fuse_request_free(struct fuse_req *req);
 757
 758 /**
 759  * Get a request, may fail with -ENOMEM,
 760  * caller should specify # elements in req->pages[] explicitly
 761  */
 762 struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages);
 763 struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
 764                                              unsigned npages);
 765
 766 /*
 767  * Increment reference count on request
 768  */
 769 void __fuse_get_request(struct fuse_req *req);
 770
 771 /**
 772  * Gets a requests for a file operation, always succeeds
 773  */
 774 struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
 775                                              struct file *file);
 776
 777 /**
 778  * Decrement reference count of a request.  If count goes to zero free
 779  * the request.
 780  */
 781 void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req);
 782
 783 /**
 784  * Send a request (synchronous)
 785  */
 786 void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req);
 787
 788 /**
 789  * Simple request sending that does request allocation and freeing
 790  */
 791 ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args);
 792
 793 /**
 794  * Send a request in the background
 795  */
 796 void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req);
 797
 798 void fuse_request_send_background_locked(struct fuse_conn *fc,
 799                                          struct fuse_req *req);
 800
 801 /* Abort all requests */
 802 void fuse_abort_conn(struct fuse_conn *fc);
 803
 804 /**
 805  * Invalidate inode attributes
 806  */
 807 void fuse_invalidate_attr(struct inode *inode);
 808
 809 void fuse_invalidate_entry_cache(struct dentry *entry);
 810
 811 void fuse_invalidate_atime(struct inode *inode);
 812
 813 /**
 814  * Acquire reference to fuse_conn
 815  */
 816 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc);
 817
 818 /**
 819  * Initialize fuse_conn
 820  */
 821 void fuse_conn_init(struct fuse_conn *fc);
 822
 823 /**
 824  * Release reference to fuse_conn
 825  */
 826 void fuse_conn_put(struct fuse_conn *fc);
 827
 828 /**
 829  * Add connection to control filesystem
 830  */
 831 int fuse_ctl_add_conn(struct fuse_conn *fc);
 832
 833 /**
 834  * Remove connection from control filesystem
 835  */
 836 void fuse_ctl_remove_conn(struct fuse_conn *fc);
 837
 838 /**
 839  * Is file type valid?
 840  */
 841 int fuse_valid_type(int m);
 842
 843 /**
 844  * Is current process allowed to perform filesystem operation?
 845  */
 846 int fuse_allow_current_process(struct fuse_conn *fc);
 847
 848 u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id);
 849
 850 int fuse_update_attributes(struct inode *inode, struct kstat *stat,
 851                            struct file *file, bool *refreshed);
 852
 853 void fuse_flush_writepages(struct inode *inode);
 854
 855 void fuse_set_nowrite(struct inode *inode);
 856 void fuse_release_nowrite(struct inode *inode);
 857
 858 u64 fuse_get_attr_version(struct fuse_conn *fc);
 859
 860 /**
 861  * File-system tells the kernel to invalidate cache for the given node id.
 862  */
 863 int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
 864                              loff_t offset, loff_t len);
 865
 866 /**
 867  * File-system tells the kernel to invalidate parent attributes and
 868  * the dentry matching parent/name.
 869  *
 870  * If the child_nodeid is non-zero and:
 871  *    - matches the inode number for the dentry matching parent/name,
 872  *    - is not a mount point
 873  *    - is a file or oan empty directory
 874  * then the dentry is unhashed (d_delete()).
 875  */
 876 int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid,
 877                              u64 child_nodeid, struct qstr *name);
 878
 879 int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file,
 880                  bool isdir);
 881
 882 /**
 883  * fuse_direct_io() flags
 884  */
 885
 886 /** If set, it is WRITE; otherwise - READ */
 887 #define FUSE_DIO_WRITE (1 << 0)
 888
 889 /** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */
 890 #define FUSE_DIO_CUSE  (1 << 1)
 891
 892 ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
 893                        loff_t *ppos, int flags);
 894 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
 895                    unsigned int flags);
 896 long fuse_ioctl_common(struct file *file, unsigned int cmd,
 897                        unsigned long arg, unsigned int flags);
 898 unsigned fuse_file_poll(struct file *file, poll_table *wait);
 899 int fuse_dev_release(struct inode *inode, struct file *file);
 900
 901 bool fuse_write_update_size(struct inode *inode, loff_t pos);
 902
 903 int fuse_flush_times(struct inode *inode, struct fuse_file *ff);
 904 int fuse_write_inode(struct inode *inode, struct writeback_control *wbc);
 905
 906 int fuse_do_setattr(struct inode *inode, struct iattr *attr,
 907                     struct file *file);
 908
 909 void fuse_set_initialized(struct fuse_conn *fc);
 910
 911 #endif /* _FS_FUSE_I_H */