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