1 /* 2 FUSE: Filesystem in Userspace 3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> 4 5 This program can be distributed under the terms of the GNU GPL. 6 See the file COPYING. 7 */ 8 9 #ifndef _FS_FUSE_I_H 10 #define _FS_FUSE_I_H 11 12 #ifndef pr_fmt 13 # define pr_fmt(fmt) "fuse: " fmt 14 #endif 15 16 #include <linux/fuse.h> 17 #include <linux/fs.h> 18 #include <linux/mount.h> 19 #include <linux/wait.h> 20 #include <linux/list.h> 21 #include <linux/spinlock.h> 22 #include <linux/mm.h> 23 #include <linux/backing-dev.h> 24 #include <linux/mutex.h> 25 #include <linux/rwsem.h> 26 #include <linux/rbtree.h> 27 #include <linux/poll.h> 28 #include <linux/workqueue.h> 29 #include <linux/kref.h> 30 #include <linux/xattr.h> 31 #include <linux/pid_namespace.h> 32 #include <linux/refcount.h> 33 #include <linux/user_namespace.h> 34 35 /** Default max number of pages that can be used in a single read request */ 36 #define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32 37 38 /** Maximum of max_pages received in init_out */ 39 #define FUSE_MAX_MAX_PAGES 256 40 41 /** Bias for fi->writectr, meaning new writepages must not be sent */ 42 #define FUSE_NOWRITE INT_MIN 43 44 /** It could be as large as PATH_MAX, but would that have any uses? */ 45 #define FUSE_NAME_MAX 1024 46 47 /** Number of dentries for each connection in the control filesystem */ 48 #define FUSE_CTL_NUM_DENTRIES 5 49 50 /** List of active connections */ 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 /* Which attributes are invalid */ 85 u32 inval_mask; 86 87 /** The sticky bit in inode->i_mode may have been removed, so 88 preserve the original mode */ 89 umode_t orig_i_mode; 90 91 /** 64 bit inode number */ 92 u64 orig_ino; 93 94 /** Version of last attribute change */ 95 u64 attr_version; 96 97 union { 98 /* Write related fields (regular file only) */ 99 struct { 100 /* Files usable in writepage. Protected by fi->lock */ 101 struct list_head write_files; 102 103 /* Writepages pending on truncate or fsync */ 104 struct list_head queued_writes; 105 106 /* Number of sent writes, a negative bias 107 * (FUSE_NOWRITE) means more writes are blocked */ 108 int writectr; 109 110 /* Waitq for writepage completion */ 111 wait_queue_head_t page_waitq; 112 113 /* List of writepage requestst (pending or sent) */ 114 struct list_head writepages; 115 }; 116 117 /* readdir cache (directory only) */ 118 struct { 119 /* true if fully cached */ 120 bool cached; 121 122 /* size of cache */ 123 loff_t size; 124 125 /* position at end of cache (position of next entry) */ 126 loff_t pos; 127 128 /* version of the cache */ 129 u64 version; 130 131 /* modification time of directory when cache was 132 * started */ 133 struct timespec64 mtime; 134 135 /* iversion of directory when cache was started */ 136 u64 iversion; 137 138 /* protects above fields */ 139 spinlock_t lock; 140 } rdc; 141 }; 142 143 /** Miscellaneous bits describing inode state */ 144 unsigned long state; 145 146 /** Lock for serializing lookup and readdir for back compatibility*/ 147 struct mutex mutex; 148 149 /** Lock to protect write related fields */ 150 spinlock_t lock; 151 }; 152 153 /** FUSE inode state bits */ 154 enum { 155 /** Advise readdirplus */ 156 FUSE_I_ADVISE_RDPLUS, 157 /** Initialized with readdirplus */ 158 FUSE_I_INIT_RDPLUS, 159 /** An operation changing file size is in progress */ 160 FUSE_I_SIZE_UNSTABLE, 161 }; 162 163 struct fuse_conn; 164 struct fuse_release_args; 165 166 /** FUSE specific file data */ 167 struct fuse_file { 168 /** Fuse connection for this file */ 169 struct fuse_conn *fc; 170 171 /* Argument space reserved for release */ 172 struct fuse_release_args *release_args; 173 174 /** Kernel file handle guaranteed to be unique */ 175 u64 kh; 176 177 /** File handle used by userspace */ 178 u64 fh; 179 180 /** Node id of this file */ 181 u64 nodeid; 182 183 /** Refcount */ 184 refcount_t count; 185 186 /** FOPEN_* flags returned by open */ 187 u32 open_flags; 188 189 /** Entry on inode's write_files list */ 190 struct list_head write_entry; 191 192 /* Readdir related */ 193 struct { 194 /* 195 * Protects below fields against (crazy) parallel readdir on 196 * same open file. Uncontended in the normal case. 197 */ 198 struct mutex lock; 199 200 /* Dir stream position */ 201 loff_t pos; 202 203 /* Offset in cache */ 204 loff_t cache_off; 205 206 /* Version of cache we are reading */ 207 u64 version; 208 209 } readdir; 210 211 /** RB node to be linked on fuse_conn->polled_files */ 212 struct rb_node polled_node; 213 214 /** Wait queue head for poll */ 215 wait_queue_head_t poll_wait; 216 217 /** Has flock been performed on this file? */ 218 bool flock:1; 219 }; 220 221 /** One input argument of a request */ 222 struct fuse_in_arg { 223 unsigned size; 224 const void *value; 225 }; 226 227 /** One output argument of a request */ 228 struct fuse_arg { 229 unsigned size; 230 void *value; 231 }; 232 233 /** FUSE page descriptor */ 234 struct fuse_page_desc { 235 unsigned int length; 236 unsigned int offset; 237 }; 238 239 struct fuse_args { 240 uint64_t nodeid; 241 uint32_t opcode; 242 unsigned short in_numargs; 243 unsigned short out_numargs; 244 bool force:1; 245 bool noreply:1; 246 bool nocreds:1; 247 bool in_pages:1; 248 bool out_pages:1; 249 bool out_argvar:1; 250 bool page_zeroing:1; 251 bool page_replace:1; 252 struct fuse_in_arg in_args[3]; 253 struct fuse_arg out_args[2]; 254 void (*end)(struct fuse_conn *fc, struct fuse_args *args, int error); 255 }; 256 257 struct fuse_args_pages { 258 struct fuse_args args; 259 struct page **pages; 260 struct fuse_page_desc *descs; 261 unsigned int num_pages; 262 }; 263 264 #define FUSE_ARGS(args) struct fuse_args args = {} 265 266 /** The request IO state (for asynchronous processing) */ 267 struct fuse_io_priv { 268 struct kref refcnt; 269 int async; 270 spinlock_t lock; 271 unsigned reqs; 272 ssize_t bytes; 273 size_t size; 274 __u64 offset; 275 bool write; 276 bool should_dirty; 277 int err; 278 struct kiocb *iocb; 279 struct completion *done; 280 bool blocking; 281 }; 282 283 #define FUSE_IO_PRIV_SYNC(i) \ 284 { \ 285 .refcnt = KREF_INIT(1), \ 286 .async = 0, \ 287 .iocb = i, \ 288 } 289 290 /** 291 * Request flags 292 * 293 * FR_ISREPLY: set if the request has reply 294 * FR_FORCE: force sending of the request even if interrupted 295 * FR_BACKGROUND: request is sent in the background 296 * FR_WAITING: request is counted as "waiting" 297 * FR_ABORTED: the request was aborted 298 * FR_INTERRUPTED: the request has been interrupted 299 * FR_LOCKED: data is being copied to/from the request 300 * FR_PENDING: request is not yet in userspace 301 * FR_SENT: request is in userspace, waiting for an answer 302 * FR_FINISHED: request is finished 303 * FR_PRIVATE: request is on private list 304 */ 305 enum fuse_req_flag { 306 FR_ISREPLY, 307 FR_FORCE, 308 FR_BACKGROUND, 309 FR_WAITING, 310 FR_ABORTED, 311 FR_INTERRUPTED, 312 FR_LOCKED, 313 FR_PENDING, 314 FR_SENT, 315 FR_FINISHED, 316 FR_PRIVATE, 317 }; 318 319 /** 320 * A request to the client 321 * 322 * .waitq.lock protects the following fields: 323 * - FR_ABORTED 324 * - FR_LOCKED (may also be modified under fc->lock, tested under both) 325 */ 326 struct fuse_req { 327 /** This can be on either pending processing or io lists in 328 fuse_conn */ 329 struct list_head list; 330 331 /** Entry on the interrupts list */ 332 struct list_head intr_entry; 333 334 /* Input/output arguments */ 335 struct fuse_args *args; 336 337 /** refcount */ 338 refcount_t count; 339 340 /* Request flags, updated with test/set/clear_bit() */ 341 unsigned long flags; 342 343 /* The request input header */ 344 struct { 345 struct fuse_in_header h; 346 } in; 347 348 /* The request output header */ 349 struct { 350 struct fuse_out_header h; 351 } out; 352 353 /** Used to wake up the task waiting for completion of request*/ 354 wait_queue_head_t waitq; 355 356 }; 357 358 struct fuse_iqueue { 359 /** Connection established */ 360 unsigned connected; 361 362 /** Lock protecting accesses to members of this structure */ 363 spinlock_t lock; 364 365 /** Readers of the connection are waiting on this */ 366 wait_queue_head_t waitq; 367 368 /** The next unique request id */ 369 u64 reqctr; 370 371 /** The list of pending requests */ 372 struct list_head pending; 373 374 /** Pending interrupts */ 375 struct list_head interrupts; 376 377 /** Queue of pending forgets */ 378 struct fuse_forget_link forget_list_head; 379 struct fuse_forget_link *forget_list_tail; 380 381 /** Batching of FORGET requests (positive indicates FORGET batch) */ 382 int forget_batch; 383 384 /** O_ASYNC requests */ 385 struct fasync_struct *fasync; 386 }; 387 388 #define FUSE_PQ_HASH_BITS 8 389 #define FUSE_PQ_HASH_SIZE (1 << FUSE_PQ_HASH_BITS) 390 391 struct fuse_pqueue { 392 /** Connection established */ 393 unsigned connected; 394 395 /** Lock protecting accessess to members of this structure */ 396 spinlock_t lock; 397 398 /** Hash table of requests being processed */ 399 struct list_head *processing; 400 401 /** The list of requests under I/O */ 402 struct list_head io; 403 }; 404 405 /** 406 * Fuse device instance 407 */ 408 struct fuse_dev { 409 /** Fuse connection for this device */ 410 struct fuse_conn *fc; 411 412 /** Processing queue */ 413 struct fuse_pqueue pq; 414 415 /** list entry on fc->devices */ 416 struct list_head entry; 417 }; 418 419 /** 420 * A Fuse connection. 421 * 422 * This structure is created, when the filesystem is mounted, and is 423 * destroyed, when the client device is closed and the filesystem is 424 * unmounted. 425 */ 426 struct fuse_conn { 427 /** Lock protecting accessess to members of this structure */ 428 spinlock_t lock; 429 430 /** Refcount */ 431 refcount_t count; 432 433 /** Number of fuse_dev's */ 434 atomic_t dev_count; 435 436 struct rcu_head rcu; 437 438 /** The user id for this mount */ 439 kuid_t user_id; 440 441 /** The group id for this mount */ 442 kgid_t group_id; 443 444 /** The pid namespace for this mount */ 445 struct pid_namespace *pid_ns; 446 447 /** The user namespace for this mount */ 448 struct user_namespace *user_ns; 449 450 /** Maximum read size */ 451 unsigned max_read; 452 453 /** Maximum write size */ 454 unsigned max_write; 455 456 /** Maxmum number of pages that can be used in a single request */ 457 unsigned int max_pages; 458 459 /** Input queue */ 460 struct fuse_iqueue iq; 461 462 /** The next unique kernel file handle */ 463 atomic64_t khctr; 464 465 /** rbtree of fuse_files waiting for poll events indexed by ph */ 466 struct rb_root polled_files; 467 468 /** Maximum number of outstanding background requests */ 469 unsigned max_background; 470 471 /** Number of background requests at which congestion starts */ 472 unsigned congestion_threshold; 473 474 /** Number of requests currently in the background */ 475 unsigned num_background; 476 477 /** Number of background requests currently queued for userspace */ 478 unsigned active_background; 479 480 /** The list of background requests set aside for later queuing */ 481 struct list_head bg_queue; 482 483 /** Protects: max_background, congestion_threshold, num_background, 484 * active_background, bg_queue, blocked */ 485 spinlock_t bg_lock; 486 487 /** Flag indicating that INIT reply has been received. Allocating 488 * any fuse request will be suspended until the flag is set */ 489 int initialized; 490 491 /** Flag indicating if connection is blocked. This will be 492 the case before the INIT reply is received, and if there 493 are too many outstading backgrounds requests */ 494 int blocked; 495 496 /** waitq for blocked connection */ 497 wait_queue_head_t blocked_waitq; 498 499 /** Connection established, cleared on umount, connection 500 abort and device release */ 501 unsigned connected; 502 503 /** Connection aborted via sysfs */ 504 bool aborted; 505 506 /** Connection failed (version mismatch). Cannot race with 507 setting other bitfields since it is only set once in INIT 508 reply, before any other request, and never cleared */ 509 unsigned conn_error:1; 510 511 /** Connection successful. Only set in INIT */ 512 unsigned conn_init:1; 513 514 /** Do readpages asynchronously? Only set in INIT */ 515 unsigned async_read:1; 516 517 /** Return an unique read error after abort. Only set in INIT */ 518 unsigned abort_err:1; 519 520 /** Do not send separate SETATTR request before open(O_TRUNC) */ 521 unsigned atomic_o_trunc:1; 522 523 /** Filesystem supports NFS exporting. Only set in INIT */ 524 unsigned export_support:1; 525 526 /** write-back cache policy (default is write-through) */ 527 unsigned writeback_cache:1; 528 529 /** allow parallel lookups and readdir (default is serialized) */ 530 unsigned parallel_dirops:1; 531 532 /** handle fs handles killing suid/sgid/cap on write/chown/trunc */ 533 unsigned handle_killpriv:1; 534 535 /** cache READLINK responses in page cache */ 536 unsigned cache_symlinks:1; 537 538 /* 539 * The following bitfields are only for optimization purposes 540 * and hence races in setting them will not cause malfunction 541 */ 542 543 /** Is open/release not implemented by fs? */ 544 unsigned no_open:1; 545 546 /** Is opendir/releasedir not implemented by fs? */ 547 unsigned no_opendir:1; 548 549 /** Is fsync not implemented by fs? */ 550 unsigned no_fsync:1; 551 552 /** Is fsyncdir not implemented by fs? */ 553 unsigned no_fsyncdir:1; 554 555 /** Is flush not implemented by fs? */ 556 unsigned no_flush:1; 557 558 /** Is setxattr not implemented by fs? */ 559 unsigned no_setxattr:1; 560 561 /** Is getxattr not implemented by fs? */ 562 unsigned no_getxattr:1; 563 564 /** Is listxattr not implemented by fs? */ 565 unsigned no_listxattr:1; 566 567 /** Is removexattr not implemented by fs? */ 568 unsigned no_removexattr:1; 569 570 /** Are posix file locking primitives not implemented by fs? */ 571 unsigned no_lock:1; 572 573 /** Is access not implemented by fs? */ 574 unsigned no_access:1; 575 576 /** Is create not implemented by fs? */ 577 unsigned no_create:1; 578 579 /** Is interrupt not implemented by fs? */ 580 unsigned no_interrupt:1; 581 582 /** Is bmap not implemented by fs? */ 583 unsigned no_bmap:1; 584 585 /** Is poll not implemented by fs? */ 586 unsigned no_poll:1; 587 588 /** Do multi-page cached writes */ 589 unsigned big_writes:1; 590 591 /** Don't apply umask to creation modes */ 592 unsigned dont_mask:1; 593 594 /** Are BSD file locking primitives not implemented by fs? */ 595 unsigned no_flock:1; 596 597 /** Is fallocate not implemented by fs? */ 598 unsigned no_fallocate:1; 599 600 /** Is rename with flags implemented by fs? */ 601 unsigned no_rename2:1; 602 603 /** Use enhanced/automatic page cache invalidation. */ 604 unsigned auto_inval_data:1; 605 606 /** Filesystem is fully reponsible for page cache invalidation. */ 607 unsigned explicit_inval_data:1; 608 609 /** Does the filesystem support readdirplus? */ 610 unsigned do_readdirplus:1; 611 612 /** Does the filesystem want adaptive readdirplus? */ 613 unsigned readdirplus_auto:1; 614 615 /** Does the filesystem support asynchronous direct-IO submission? */ 616 unsigned async_dio:1; 617 618 /** Is lseek not implemented by fs? */ 619 unsigned no_lseek:1; 620 621 /** Does the filesystem support posix acls? */ 622 unsigned posix_acl:1; 623 624 /** Check permissions based on the file mode or not? */ 625 unsigned default_permissions:1; 626 627 /** Allow other than the mounter user to access the filesystem ? */ 628 unsigned allow_other:1; 629 630 /** Does the filesystem support copy_file_range? */ 631 unsigned no_copy_file_range:1; 632 633 /* Send DESTROY request */ 634 unsigned int destroy:1; 635 636 /** The number of requests waiting for completion */ 637 atomic_t num_waiting; 638 639 /** Negotiated minor version */ 640 unsigned minor; 641 642 /** Entry on the fuse_conn_list */ 643 struct list_head entry; 644 645 /** Device ID from super block */ 646 dev_t dev; 647 648 /** Dentries in the control filesystem */ 649 struct dentry *ctl_dentry[FUSE_CTL_NUM_DENTRIES]; 650 651 /** number of dentries used in the above array */ 652 int ctl_ndents; 653 654 /** Key for lock owner ID scrambling */ 655 u32 scramble_key[4]; 656 657 /** Version counter for attribute changes */ 658 atomic64_t attr_version; 659 660 /** Called on final put */ 661 void (*release)(struct fuse_conn *); 662 663 /** Super block for this connection. */ 664 struct super_block *sb; 665 666 /** Read/write semaphore to hold when accessing sb. */ 667 struct rw_semaphore killsb; 668 669 /** List of device instances belonging to this connection */ 670 struct list_head devices; 671 }; 672 673 static inline struct fuse_conn *get_fuse_conn_super(struct super_block *sb) 674 { 675 return sb->s_fs_info; 676 } 677 678 static inline struct fuse_conn *get_fuse_conn(struct inode *inode) 679 { 680 return get_fuse_conn_super(inode->i_sb); 681 } 682 683 static inline struct fuse_inode *get_fuse_inode(struct inode *inode) 684 { 685 return container_of(inode, struct fuse_inode, inode); 686 } 687 688 static inline u64 get_node_id(struct inode *inode) 689 { 690 return get_fuse_inode(inode)->nodeid; 691 } 692 693 static inline int invalid_nodeid(u64 nodeid) 694 { 695 return !nodeid || nodeid == FUSE_ROOT_ID; 696 } 697 698 static inline u64 fuse_get_attr_version(struct fuse_conn *fc) 699 { 700 return atomic64_read(&fc->attr_version); 701 } 702 703 /** Device operations */ 704 extern const struct file_operations fuse_dev_operations; 705 706 extern const struct dentry_operations fuse_dentry_operations; 707 extern const struct dentry_operations fuse_root_dentry_operations; 708 709 /** 710 * Inode to nodeid comparison. 711 */ 712 int fuse_inode_eq(struct inode *inode, void *_nodeidp); 713 714 /** 715 * Get a filled in inode 716 */ 717 struct inode *fuse_iget(struct super_block *sb, u64 nodeid, 718 int generation, struct fuse_attr *attr, 719 u64 attr_valid, u64 attr_version); 720 721 int fuse_lookup_name(struct super_block *sb, u64 nodeid, const struct qstr *name, 722 struct fuse_entry_out *outarg, struct inode **inode); 723 724 /** 725 * Send FORGET command 726 */ 727 void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget, 728 u64 nodeid, u64 nlookup); 729 730 struct fuse_forget_link *fuse_alloc_forget(void); 731 732 /* 733 * Initialize READ or READDIR request 734 */ 735 struct fuse_io_args { 736 union { 737 struct { 738 struct fuse_read_in in; 739 u64 attr_ver; 740 } read; 741 struct { 742 struct fuse_write_in in; 743 struct fuse_write_out out; 744 } write; 745 }; 746 struct fuse_args_pages ap; 747 struct fuse_io_priv *io; 748 struct fuse_file *ff; 749 }; 750 751 void fuse_read_args_fill(struct fuse_io_args *ia, struct file *file, loff_t pos, 752 size_t count, int opcode); 753 754 755 /** 756 * Send OPEN or OPENDIR request 757 */ 758 int fuse_open_common(struct inode *inode, struct file *file, bool isdir); 759 760 struct fuse_file *fuse_file_alloc(struct fuse_conn *fc); 761 void fuse_file_free(struct fuse_file *ff); 762 void fuse_finish_open(struct inode *inode, struct file *file); 763 764 void fuse_sync_release(struct fuse_inode *fi, struct fuse_file *ff, int flags); 765 766 /** 767 * Send RELEASE or RELEASEDIR request 768 */ 769 void fuse_release_common(struct file *file, bool isdir); 770 771 /** 772 * Send FSYNC or FSYNCDIR request 773 */ 774 int fuse_fsync_common(struct file *file, loff_t start, loff_t end, 775 int datasync, int opcode); 776 777 /** 778 * Notify poll wakeup 779 */ 780 int fuse_notify_poll_wakeup(struct fuse_conn *fc, 781 struct fuse_notify_poll_wakeup_out *outarg); 782 783 /** 784 * Initialize file operations on a regular file 785 */ 786 void fuse_init_file_inode(struct inode *inode); 787 788 /** 789 * Initialize inode operations on regular files and special files 790 */ 791 void fuse_init_common(struct inode *inode); 792 793 /** 794 * Initialize inode and file operations on a directory 795 */ 796 void fuse_init_dir(struct inode *inode); 797 798 /** 799 * Initialize inode operations on a symlink 800 */ 801 void fuse_init_symlink(struct inode *inode); 802 803 /** 804 * Change attributes of an inode 805 */ 806 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr, 807 u64 attr_valid, u64 attr_version); 808 809 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, 810 u64 attr_valid); 811 812 /** 813 * Initialize the client device 814 */ 815 int fuse_dev_init(void); 816 817 /** 818 * Cleanup the client device 819 */ 820 void fuse_dev_cleanup(void); 821 822 int fuse_ctl_init(void); 823 void __exit fuse_ctl_cleanup(void); 824 825 /** 826 * Simple request sending that does request allocation and freeing 827 */ 828 ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args); 829 int fuse_simple_background(struct fuse_conn *fc, struct fuse_args *args, 830 gfp_t gfp_flags); 831 832 /** 833 * End a finished request 834 */ 835 void fuse_request_end(struct fuse_conn *fc, struct fuse_req *req); 836 837 /* Abort all requests */ 838 void fuse_abort_conn(struct fuse_conn *fc); 839 void fuse_wait_aborted(struct fuse_conn *fc); 840 841 /** 842 * Invalidate inode attributes 843 */ 844 void fuse_invalidate_attr(struct inode *inode); 845 846 void fuse_invalidate_entry_cache(struct dentry *entry); 847 848 void fuse_invalidate_atime(struct inode *inode); 849 850 u64 entry_attr_timeout(struct fuse_entry_out *o); 851 void fuse_change_entry_timeout(struct dentry *entry, struct fuse_entry_out *o); 852 853 /** 854 * Acquire reference to fuse_conn 855 */ 856 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc); 857 858 /** 859 * Initialize fuse_conn 860 */ 861 void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns); 862 863 /** 864 * Release reference to fuse_conn 865 */ 866 void fuse_conn_put(struct fuse_conn *fc); 867 868 struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc); 869 void fuse_dev_free(struct fuse_dev *fud); 870 871 /** 872 * Add connection to control filesystem 873 */ 874 int fuse_ctl_add_conn(struct fuse_conn *fc); 875 876 /** 877 * Remove connection from control filesystem 878 */ 879 void fuse_ctl_remove_conn(struct fuse_conn *fc); 880 881 /** 882 * Is file type valid? 883 */ 884 int fuse_valid_type(int m); 885 886 /** 887 * Is current process allowed to perform filesystem operation? 888 */ 889 int fuse_allow_current_process(struct fuse_conn *fc); 890 891 u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id); 892 893 void fuse_update_ctime(struct inode *inode); 894 895 int fuse_update_attributes(struct inode *inode, struct file *file); 896 897 void fuse_flush_writepages(struct inode *inode); 898 899 void fuse_set_nowrite(struct inode *inode); 900 void fuse_release_nowrite(struct inode *inode); 901 902 /** 903 * File-system tells the kernel to invalidate cache for the given node id. 904 */ 905 int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid, 906 loff_t offset, loff_t len); 907 908 /** 909 * File-system tells the kernel to invalidate parent attributes and 910 * the dentry matching parent/name. 911 * 912 * If the child_nodeid is non-zero and: 913 * - matches the inode number for the dentry matching parent/name, 914 * - is not a mount point 915 * - is a file or oan empty directory 916 * then the dentry is unhashed (d_delete()). 917 */ 918 int fuse_reverse_inval_entry(struct super_block *sb, u64 parent_nodeid, 919 u64 child_nodeid, struct qstr *name); 920 921 int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file, 922 bool isdir); 923 924 /** 925 * fuse_direct_io() flags 926 */ 927 928 /** If set, it is WRITE; otherwise - READ */ 929 #define FUSE_DIO_WRITE (1 << 0) 930 931 /** CUSE pass fuse_direct_io() a file which f_mapping->host is not from FUSE */ 932 #define FUSE_DIO_CUSE (1 << 1) 933 934 ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter, 935 loff_t *ppos, int flags); 936 long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, 937 unsigned int flags); 938 long fuse_ioctl_common(struct file *file, unsigned int cmd, 939 unsigned long arg, unsigned int flags); 940 __poll_t fuse_file_poll(struct file *file, poll_table *wait); 941 int fuse_dev_release(struct inode *inode, struct file *file); 942 943 bool fuse_write_update_size(struct inode *inode, loff_t pos); 944 945 int fuse_flush_times(struct inode *inode, struct fuse_file *ff); 946 int fuse_write_inode(struct inode *inode, struct writeback_control *wbc); 947 948 int fuse_do_setattr(struct dentry *dentry, struct iattr *attr, 949 struct file *file); 950 951 void fuse_set_initialized(struct fuse_conn *fc); 952 953 void fuse_unlock_inode(struct inode *inode, bool locked); 954 bool fuse_lock_inode(struct inode *inode); 955 956 int fuse_setxattr(struct inode *inode, const char *name, const void *value, 957 size_t size, int flags); 958 ssize_t fuse_getxattr(struct inode *inode, const char *name, void *value, 959 size_t size); 960 ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size); 961 int fuse_removexattr(struct inode *inode, const char *name); 962 extern const struct xattr_handler *fuse_xattr_handlers[]; 963 extern const struct xattr_handler *fuse_acl_xattr_handlers[]; 964 extern const struct xattr_handler *fuse_no_acl_xattr_handlers[]; 965 966 struct posix_acl; 967 struct posix_acl *fuse_get_acl(struct inode *inode, int type); 968 int fuse_set_acl(struct inode *inode, struct posix_acl *acl, int type); 969 970 971 /* readdir.c */ 972 int fuse_readdir(struct file *file, struct dir_context *ctx); 973 974 #endif /* _FS_FUSE_I_H */ 975