1 #ifndef _LINUX_FS_H 2 #define _LINUX_FS_H 3 4 /* 5 * This file has definitions for some important file table 6 * structures etc. 7 */ 8 9 #include <linux/limits.h> 10 #include <linux/ioctl.h> 11 12 /* 13 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change 14 * the file limit at runtime and only root can increase the per-process 15 * nr_file rlimit, so it's safe to set up a ridiculously high absolute 16 * upper limit on files-per-process. 17 * 18 * Some programs (notably those using select()) may have to be 19 * recompiled to take full advantage of the new limits.. 20 */ 21 22 /* Fixed constants first: */ 23 #undef NR_OPEN 24 #define NR_OPEN (1024*1024) /* Absolute upper limit on fd num */ 25 #define INR_OPEN 1024 /* Initial setting for nfile rlimits */ 26 27 #define BLOCK_SIZE_BITS 10 28 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS) 29 30 #define SEEK_SET 0 /* seek relative to beginning of file */ 31 #define SEEK_CUR 1 /* seek relative to current file position */ 32 #define SEEK_END 2 /* seek relative to end of file */ 33 34 /* And dynamically-tunable limits and defaults: */ 35 struct files_stat_struct { 36 int nr_files; /* read only */ 37 int nr_free_files; /* read only */ 38 int max_files; /* tunable */ 39 }; 40 extern struct files_stat_struct files_stat; 41 extern int get_max_files(void); 42 43 struct inodes_stat_t { 44 int nr_inodes; 45 int nr_unused; 46 int dummy[5]; 47 }; 48 extern struct inodes_stat_t inodes_stat; 49 50 extern int leases_enable, lease_break_time; 51 52 #ifdef CONFIG_DNOTIFY 53 extern int dir_notify_enable; 54 #endif 55 56 #define NR_FILE 8192 /* this can well be larger on a larger system */ 57 58 #define MAY_EXEC 1 59 #define MAY_WRITE 2 60 #define MAY_READ 4 61 #define MAY_APPEND 8 62 63 #define FMODE_READ 1 64 #define FMODE_WRITE 2 65 66 /* Internal kernel extensions */ 67 #define FMODE_LSEEK 4 68 #define FMODE_PREAD 8 69 #define FMODE_PWRITE FMODE_PREAD /* These go hand in hand */ 70 71 /* File is being opened for execution. Primary users of this flag are 72 distributed filesystems that can use it to achieve correct ETXTBUSY 73 behavior for cross-node execution/opening_for_writing of files */ 74 #define FMODE_EXEC 16 75 76 #define RW_MASK 1 77 #define RWA_MASK 2 78 #define READ 0 79 #define WRITE 1 80 #define READA 2 /* read-ahead - don't block if no resources */ 81 #define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */ 82 #define SPECIAL 4 /* For non-blockdevice requests in request queue */ 83 #define READ_SYNC (READ | (1 << BIO_RW_SYNC)) 84 #define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC)) 85 #define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER)) 86 87 #define SEL_IN 1 88 #define SEL_OUT 2 89 #define SEL_EX 4 90 91 /* public flags for file_system_type */ 92 #define FS_REQUIRES_DEV 1 93 #define FS_BINARY_MOUNTDATA 2 94 #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */ 95 #define FS_ODD_RENAME 32768 /* Temporary stuff; will go away as soon 96 * as nfs_rename() will be cleaned up 97 */ 98 /* 99 * These are the fs-independent mount-flags: up to 32 flags are supported 100 */ 101 #define MS_RDONLY 1 /* Mount read-only */ 102 #define MS_NOSUID 2 /* Ignore suid and sgid bits */ 103 #define MS_NODEV 4 /* Disallow access to device special files */ 104 #define MS_NOEXEC 8 /* Disallow program execution */ 105 #define MS_SYNCHRONOUS 16 /* Writes are synced at once */ 106 #define MS_REMOUNT 32 /* Alter flags of a mounted FS */ 107 #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */ 108 #define MS_DIRSYNC 128 /* Directory modifications are synchronous */ 109 #define MS_NOATIME 1024 /* Do not update access times. */ 110 #define MS_NODIRATIME 2048 /* Do not update directory access times */ 111 #define MS_BIND 4096 112 #define MS_MOVE 8192 113 #define MS_REC 16384 114 #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence. 115 MS_VERBOSE is deprecated. */ 116 #define MS_SILENT 32768 117 #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */ 118 #define MS_UNBINDABLE (1<<17) /* change to unbindable */ 119 #define MS_PRIVATE (1<<18) /* change to private */ 120 #define MS_SLAVE (1<<19) /* change to slave */ 121 #define MS_SHARED (1<<20) /* change to shared */ 122 #define MS_ACTIVE (1<<30) 123 #define MS_NOUSER (1<<31) 124 125 /* 126 * Superblock flags that can be altered by MS_REMOUNT 127 */ 128 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK) 129 130 /* 131 * Old magic mount flag and mask 132 */ 133 #define MS_MGC_VAL 0xC0ED0000 134 #define MS_MGC_MSK 0xffff0000 135 136 /* Inode flags - they have nothing to superblock flags now */ 137 138 #define S_SYNC 1 /* Writes are synced at once */ 139 #define S_NOATIME 2 /* Do not update access times */ 140 #define S_APPEND 4 /* Append-only file */ 141 #define S_IMMUTABLE 8 /* Immutable file */ 142 #define S_DEAD 16 /* removed, but still open directory */ 143 #define S_NOQUOTA 32 /* Inode is not counted to quota */ 144 #define S_DIRSYNC 64 /* Directory modifications are synchronous */ 145 #define S_NOCMTIME 128 /* Do not update file c/mtime */ 146 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */ 147 #define S_PRIVATE 512 /* Inode is fs-internal */ 148 149 /* 150 * Note that nosuid etc flags are inode-specific: setting some file-system 151 * flags just means all the inodes inherit those flags by default. It might be 152 * possible to override it selectively if you really wanted to with some 153 * ioctl() that is not currently implemented. 154 * 155 * Exception: MS_RDONLY is always applied to the entire file system. 156 * 157 * Unfortunately, it is possible to change a filesystems flags with it mounted 158 * with files in use. This means that all of the inodes will not have their 159 * i_flags updated. Hence, i_flags no longer inherit the superblock mount 160 * flags, so these have to be checked separately. -- rmk (at) arm.uk.linux.org 161 */ 162 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg)) 163 164 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY) 165 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \ 166 ((inode)->i_flags & S_SYNC)) 167 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \ 168 ((inode)->i_flags & (S_SYNC|S_DIRSYNC))) 169 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK) 170 171 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA) 172 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND) 173 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE) 174 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL) 175 176 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD) 177 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME) 178 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE) 179 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE) 180 181 /* the read-only stuff doesn't really belong here, but any other place is 182 probably as bad and I don't want to create yet another include file. */ 183 184 #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */ 185 #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */ 186 #define BLKRRPART _IO(0x12,95) /* re-read partition table */ 187 #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */ 188 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */ 189 #define BLKRASET _IO(0x12,98) /* set read ahead for block device */ 190 #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */ 191 #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */ 192 #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */ 193 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */ 194 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */ 195 #define BLKSSZGET _IO(0x12,104)/* get block device sector size */ 196 #if 0 197 #define BLKPG _IO(0x12,105)/* See blkpg.h */ 198 199 /* Some people are morons. Do not use sizeof! */ 200 201 #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */ 202 #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */ 203 /* This was here just to show that the number is taken - 204 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */ 205 #endif 206 /* A jump here: 108-111 have been used for various private purposes. */ 207 #define BLKBSZGET _IOR(0x12,112,size_t) 208 #define BLKBSZSET _IOW(0x12,113,size_t) 209 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ 210 #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup) 211 #define BLKTRACESTART _IO(0x12,116) 212 #define BLKTRACESTOP _IO(0x12,117) 213 #define BLKTRACETEARDOWN _IO(0x12,118) 214 215 #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ 216 #define FIBMAP _IO(0x00,1) /* bmap access */ 217 #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */ 218 219 #define SYNC_FILE_RANGE_WAIT_BEFORE 1 220 #define SYNC_FILE_RANGE_WRITE 2 221 #define SYNC_FILE_RANGE_WAIT_AFTER 4 222 223 #ifdef __KERNEL__ 224 225 #include <linux/linkage.h> 226 #include <linux/wait.h> 227 #include <linux/types.h> 228 #include <linux/kdev_t.h> 229 #include <linux/dcache.h> 230 #include <linux/stat.h> 231 #include <linux/cache.h> 232 #include <linux/kobject.h> 233 #include <linux/list.h> 234 #include <linux/radix-tree.h> 235 #include <linux/prio_tree.h> 236 #include <linux/init.h> 237 #include <linux/sched.h> 238 #include <linux/mutex.h> 239 240 #include <asm/atomic.h> 241 #include <asm/semaphore.h> 242 #include <asm/byteorder.h> 243 244 struct hd_geometry; 245 struct iovec; 246 struct nameidata; 247 struct kiocb; 248 struct pipe_inode_info; 249 struct poll_table_struct; 250 struct kstatfs; 251 struct vm_area_struct; 252 struct vfsmount; 253 254 extern void __init inode_init(unsigned long); 255 extern void __init inode_init_early(void); 256 extern void __init mnt_init(unsigned long); 257 extern void __init files_init(unsigned long); 258 259 struct buffer_head; 260 typedef int (get_block_t)(struct inode *inode, sector_t iblock, 261 struct buffer_head *bh_result, int create); 262 typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset, 263 ssize_t bytes, void *private); 264 265 /* 266 * Attribute flags. These should be or-ed together to figure out what 267 * has been changed! 268 */ 269 #define ATTR_MODE 1 270 #define ATTR_UID 2 271 #define ATTR_GID 4 272 #define ATTR_SIZE 8 273 #define ATTR_ATIME 16 274 #define ATTR_MTIME 32 275 #define ATTR_CTIME 64 276 #define ATTR_ATIME_SET 128 277 #define ATTR_MTIME_SET 256 278 #define ATTR_FORCE 512 /* Not a change, but a change it */ 279 #define ATTR_ATTR_FLAG 1024 280 #define ATTR_KILL_SUID 2048 281 #define ATTR_KILL_SGID 4096 282 #define ATTR_FILE 8192 283 284 /* 285 * This is the Inode Attributes structure, used for notify_change(). It 286 * uses the above definitions as flags, to know which values have changed. 287 * Also, in this manner, a Filesystem can look at only the values it cares 288 * about. Basically, these are the attributes that the VFS layer can 289 * request to change from the FS layer. 290 * 291 * Derek Atkins <warlord (at) MIT.EDU> 94-10-20 292 */ 293 struct iattr { 294 unsigned int ia_valid; 295 umode_t ia_mode; 296 uid_t ia_uid; 297 gid_t ia_gid; 298 loff_t ia_size; 299 struct timespec ia_atime; 300 struct timespec ia_mtime; 301 struct timespec ia_ctime; 302 303 /* 304 * Not an attribute, but an auxilary info for filesystems wanting to 305 * implement an ftruncate() like method. NOTE: filesystem should 306 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL). 307 */ 308 struct file *ia_file; 309 }; 310 311 /* 312 * Includes for diskquotas. 313 */ 314 #include <linux/quota.h> 315 316 /** 317 * enum positive_aop_returns - aop return codes with specific semantics 318 * 319 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has 320 * completed, that the page is still locked, and 321 * should be considered active. The VM uses this hint 322 * to return the page to the active list -- it won't 323 * be a candidate for writeback again in the near 324 * future. Other callers must be careful to unlock 325 * the page if they get this return. Returned by 326 * writepage(); 327 * 328 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has 329 * unlocked it and the page might have been truncated. 330 * The caller should back up to acquiring a new page and 331 * trying again. The aop will be taking reasonable 332 * precautions not to livelock. If the caller held a page 333 * reference, it should drop it before retrying. Returned 334 * by readpage(), prepare_write(), and commit_write(). 335 * 336 * address_space_operation functions return these large constants to indicate 337 * special semantics to the caller. These are much larger than the bytes in a 338 * page to allow for functions that return the number of bytes operated on in a 339 * given page. 340 */ 341 342 enum positive_aop_returns { 343 AOP_WRITEPAGE_ACTIVATE = 0x80000, 344 AOP_TRUNCATED_PAGE = 0x80001, 345 }; 346 347 /* 348 * oh the beauties of C type declarations. 349 */ 350 struct page; 351 struct address_space; 352 struct writeback_control; 353 354 struct address_space_operations { 355 int (*writepage)(struct page *page, struct writeback_control *wbc); 356 int (*readpage)(struct file *, struct page *); 357 void (*sync_page)(struct page *); 358 359 /* Write back some dirty pages from this mapping. */ 360 int (*writepages)(struct address_space *, struct writeback_control *); 361 362 /* Set a page dirty. Return true if this dirtied it */ 363 int (*set_page_dirty)(struct page *page); 364 365 int (*readpages)(struct file *filp, struct address_space *mapping, 366 struct list_head *pages, unsigned nr_pages); 367 368 /* 369 * ext3 requires that a successful prepare_write() call be followed 370 * by a commit_write() call - they must be balanced 371 */ 372 int (*prepare_write)(struct file *, struct page *, unsigned, unsigned); 373 int (*commit_write)(struct file *, struct page *, unsigned, unsigned); 374 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */ 375 sector_t (*bmap)(struct address_space *, sector_t); 376 void (*invalidatepage) (struct page *, unsigned long); 377 int (*releasepage) (struct page *, gfp_t); 378 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov, 379 loff_t offset, unsigned long nr_segs); 380 struct page* (*get_xip_page)(struct address_space *, sector_t, 381 int); 382 /* migrate the contents of a page to the specified target */ 383 int (*migratepage) (struct address_space *, 384 struct page *, struct page *); 385 }; 386 387 struct backing_dev_info; 388 struct address_space { 389 struct inode *host; /* owner: inode, block_device */ 390 struct radix_tree_root page_tree; /* radix tree of all pages */ 391 rwlock_t tree_lock; /* and rwlock protecting it */ 392 unsigned int i_mmap_writable;/* count VM_SHARED mappings */ 393 struct prio_tree_root i_mmap; /* tree of private and shared mappings */ 394 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */ 395 spinlock_t i_mmap_lock; /* protect tree, count, list */ 396 unsigned int truncate_count; /* Cover race condition with truncate */ 397 unsigned long nrpages; /* number of total pages */ 398 pgoff_t writeback_index;/* writeback starts here */ 399 const struct address_space_operations *a_ops; /* methods */ 400 unsigned long flags; /* error bits/gfp mask */ 401 struct backing_dev_info *backing_dev_info; /* device readahead, etc */ 402 spinlock_t private_lock; /* for use by the address_space */ 403 struct list_head private_list; /* ditto */ 404 struct address_space *assoc_mapping; /* ditto */ 405 } __attribute__((aligned(sizeof(long)))); 406 /* 407 * On most architectures that alignment is already the case; but 408 * must be enforced here for CRIS, to let the least signficant bit 409 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON. 410 */ 411 412 struct block_device { 413 dev_t bd_dev; /* not a kdev_t - it's a search key */ 414 struct inode * bd_inode; /* will die */ 415 int bd_openers; 416 struct mutex bd_mutex; /* open/close mutex */ 417 struct mutex bd_mount_mutex; /* mount mutex */ 418 struct list_head bd_inodes; 419 void * bd_holder; 420 int bd_holders; 421 #ifdef CONFIG_SYSFS 422 struct list_head bd_holder_list; 423 #endif 424 struct block_device * bd_contains; 425 unsigned bd_block_size; 426 struct hd_struct * bd_part; 427 /* number of times partitions within this device have been opened. */ 428 unsigned bd_part_count; 429 int bd_invalidated; 430 struct gendisk * bd_disk; 431 struct list_head bd_list; 432 struct backing_dev_info *bd_inode_backing_dev_info; 433 /* 434 * Private data. You must have bd_claim'ed the block_device 435 * to use this. NOTE: bd_claim allows an owner to claim 436 * the same device multiple times, the owner must take special 437 * care to not mess up bd_private for that case. 438 */ 439 unsigned long bd_private; 440 }; 441 442 /* 443 * bdev->bd_mutex nesting subclasses for the lock validator: 444 * 445 * 0: normal 446 * 1: 'whole' 447 * 2: 'partition' 448 */ 449 enum bdev_bd_mutex_lock_class 450 { 451 BD_MUTEX_NORMAL, 452 BD_MUTEX_WHOLE, 453 BD_MUTEX_PARTITION 454 }; 455 456 457 /* 458 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache 459 * radix trees 460 */ 461 #define PAGECACHE_TAG_DIRTY 0 462 #define PAGECACHE_TAG_WRITEBACK 1 463 464 int mapping_tagged(struct address_space *mapping, int tag); 465 466 /* 467 * Might pages of this file be mapped into userspace? 468 */ 469 static inline int mapping_mapped(struct address_space *mapping) 470 { 471 return !prio_tree_empty(&mapping->i_mmap) || 472 !list_empty(&mapping->i_mmap_nonlinear); 473 } 474 475 /* 476 * Might pages of this file have been modified in userspace? 477 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff 478 * marks vma as VM_SHARED if it is shared, and the file was opened for 479 * writing i.e. vma may be mprotected writable even if now readonly. 480 */ 481 static inline int mapping_writably_mapped(struct address_space *mapping) 482 { 483 return mapping->i_mmap_writable != 0; 484 } 485 486 /* 487 * Use sequence counter to get consistent i_size on 32-bit processors. 488 */ 489 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 490 #include <linux/seqlock.h> 491 #define __NEED_I_SIZE_ORDERED 492 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount) 493 #else 494 #define i_size_ordered_init(inode) do { } while (0) 495 #endif 496 497 struct inode { 498 struct hlist_node i_hash; 499 struct list_head i_list; 500 struct list_head i_sb_list; 501 struct list_head i_dentry; 502 unsigned long i_ino; 503 atomic_t i_count; 504 umode_t i_mode; 505 unsigned int i_nlink; 506 uid_t i_uid; 507 gid_t i_gid; 508 dev_t i_rdev; 509 loff_t i_size; 510 struct timespec i_atime; 511 struct timespec i_mtime; 512 struct timespec i_ctime; 513 unsigned int i_blkbits; 514 unsigned long i_blksize; 515 unsigned long i_version; 516 blkcnt_t i_blocks; 517 unsigned short i_bytes; 518 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */ 519 struct mutex i_mutex; 520 struct rw_semaphore i_alloc_sem; 521 struct inode_operations *i_op; 522 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */ 523 struct super_block *i_sb; 524 struct file_lock *i_flock; 525 struct address_space *i_mapping; 526 struct address_space i_data; 527 #ifdef CONFIG_QUOTA 528 struct dquot *i_dquot[MAXQUOTAS]; 529 #endif 530 /* These three should probably be a union */ 531 struct list_head i_devices; 532 struct pipe_inode_info *i_pipe; 533 struct block_device *i_bdev; 534 struct cdev *i_cdev; 535 int i_cindex; 536 537 __u32 i_generation; 538 539 #ifdef CONFIG_DNOTIFY 540 unsigned long i_dnotify_mask; /* Directory notify events */ 541 struct dnotify_struct *i_dnotify; /* for directory notifications */ 542 #endif 543 544 #ifdef CONFIG_INOTIFY 545 struct list_head inotify_watches; /* watches on this inode */ 546 struct mutex inotify_mutex; /* protects the watches list */ 547 #endif 548 549 unsigned long i_state; 550 unsigned long dirtied_when; /* jiffies of first dirtying */ 551 552 unsigned int i_flags; 553 554 atomic_t i_writecount; 555 void *i_security; 556 union { 557 void *generic_ip; 558 } u; 559 #ifdef __NEED_I_SIZE_ORDERED 560 seqcount_t i_size_seqcount; 561 #endif 562 }; 563 564 /* 565 * inode->i_mutex nesting subclasses for the lock validator: 566 * 567 * 0: the object of the current VFS operation 568 * 1: parent 569 * 2: child/target 570 * 3: quota file 571 * 572 * The locking order between these classes is 573 * parent -> child -> normal -> xattr -> quota 574 */ 575 enum inode_i_mutex_lock_class 576 { 577 I_MUTEX_NORMAL, 578 I_MUTEX_PARENT, 579 I_MUTEX_CHILD, 580 I_MUTEX_XATTR, 581 I_MUTEX_QUOTA 582 }; 583 584 /* 585 * NOTE: in a 32bit arch with a preemptable kernel and 586 * an UP compile the i_size_read/write must be atomic 587 * with respect to the local cpu (unlike with preempt disabled), 588 * but they don't need to be atomic with respect to other cpus like in 589 * true SMP (so they need either to either locally disable irq around 590 * the read or for example on x86 they can be still implemented as a 591 * cmpxchg8b without the need of the lock prefix). For SMP compiles 592 * and 64bit archs it makes no difference if preempt is enabled or not. 593 */ 594 static inline loff_t i_size_read(struct inode *inode) 595 { 596 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 597 loff_t i_size; 598 unsigned int seq; 599 600 do { 601 seq = read_seqcount_begin(&inode->i_size_seqcount); 602 i_size = inode->i_size; 603 } while (read_seqcount_retry(&inode->i_size_seqcount, seq)); 604 return i_size; 605 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) 606 loff_t i_size; 607 608 preempt_disable(); 609 i_size = inode->i_size; 610 preempt_enable(); 611 return i_size; 612 #else 613 return inode->i_size; 614 #endif 615 } 616 617 618 static inline void i_size_write(struct inode *inode, loff_t i_size) 619 { 620 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 621 write_seqcount_begin(&inode->i_size_seqcount); 622 inode->i_size = i_size; 623 write_seqcount_end(&inode->i_size_seqcount); 624 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) 625 preempt_disable(); 626 inode->i_size = i_size; 627 preempt_enable(); 628 #else 629 inode->i_size = i_size; 630 #endif 631 } 632 633 static inline unsigned iminor(struct inode *inode) 634 { 635 return MINOR(inode->i_rdev); 636 } 637 638 static inline unsigned imajor(struct inode *inode) 639 { 640 return MAJOR(inode->i_rdev); 641 } 642 643 extern struct block_device *I_BDEV(struct inode *inode); 644 645 struct fown_struct { 646 rwlock_t lock; /* protects pid, uid, euid fields */ 647 int pid; /* pid or -pgrp where SIGIO should be sent */ 648 uid_t uid, euid; /* uid/euid of process setting the owner */ 649 void *security; 650 int signum; /* posix.1b rt signal to be delivered on IO */ 651 }; 652 653 /* 654 * Track a single file's readahead state 655 */ 656 struct file_ra_state { 657 unsigned long start; /* Current window */ 658 unsigned long size; 659 unsigned long flags; /* ra flags RA_FLAG_xxx*/ 660 unsigned long cache_hit; /* cache hit count*/ 661 unsigned long prev_page; /* Cache last read() position */ 662 unsigned long ahead_start; /* Ahead window */ 663 unsigned long ahead_size; 664 unsigned long ra_pages; /* Maximum readahead window */ 665 unsigned long mmap_hit; /* Cache hit stat for mmap accesses */ 666 unsigned long mmap_miss; /* Cache miss stat for mmap accesses */ 667 }; 668 #define RA_FLAG_MISS 0x01 /* a cache miss occured against this file */ 669 #define RA_FLAG_INCACHE 0x02 /* file is already in cache */ 670 671 struct file { 672 /* 673 * fu_list becomes invalid after file_free is called and queued via 674 * fu_rcuhead for RCU freeing 675 */ 676 union { 677 struct list_head fu_list; 678 struct rcu_head fu_rcuhead; 679 } f_u; 680 struct dentry *f_dentry; 681 struct vfsmount *f_vfsmnt; 682 const struct file_operations *f_op; 683 atomic_t f_count; 684 unsigned int f_flags; 685 mode_t f_mode; 686 loff_t f_pos; 687 struct fown_struct f_owner; 688 unsigned int f_uid, f_gid; 689 struct file_ra_state f_ra; 690 691 unsigned long f_version; 692 void *f_security; 693 694 /* needed for tty driver, and maybe others */ 695 void *private_data; 696 697 #ifdef CONFIG_EPOLL 698 /* Used by fs/eventpoll.c to link all the hooks to this file */ 699 struct list_head f_ep_links; 700 spinlock_t f_ep_lock; 701 #endif /* #ifdef CONFIG_EPOLL */ 702 struct address_space *f_mapping; 703 }; 704 extern spinlock_t files_lock; 705 #define file_list_lock() spin_lock(&files_lock); 706 #define file_list_unlock() spin_unlock(&files_lock); 707 708 #define get_file(x) atomic_inc(&(x)->f_count) 709 #define file_count(x) atomic_read(&(x)->f_count) 710 711 #define MAX_NON_LFS ((1UL<<31) - 1) 712 713 /* Page cache limit. The filesystems should put that into their s_maxbytes 714 limits, otherwise bad things can happen in VM. */ 715 #if BITS_PER_LONG==32 716 #define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1) 717 #elif BITS_PER_LONG==64 718 #define MAX_LFS_FILESIZE 0x7fffffffffffffffUL 719 #endif 720 721 #define FL_POSIX 1 722 #define FL_FLOCK 2 723 #define FL_ACCESS 8 /* not trying to lock, just looking */ 724 #define FL_EXISTS 16 /* when unlocking, test for existence */ 725 #define FL_LEASE 32 /* lease held on this file */ 726 #define FL_CLOSE 64 /* unlock on close */ 727 #define FL_SLEEP 128 /* A blocking lock */ 728 729 /* 730 * The POSIX file lock owner is determined by 731 * the "struct files_struct" in the thread group 732 * (or NULL for no owner - BSD locks). 733 * 734 * Lockd stuffs a "host" pointer into this. 735 */ 736 typedef struct files_struct *fl_owner_t; 737 738 struct file_lock_operations { 739 void (*fl_insert)(struct file_lock *); /* lock insertion callback */ 740 void (*fl_remove)(struct file_lock *); /* lock removal callback */ 741 void (*fl_copy_lock)(struct file_lock *, struct file_lock *); 742 void (*fl_release_private)(struct file_lock *); 743 }; 744 745 struct lock_manager_operations { 746 int (*fl_compare_owner)(struct file_lock *, struct file_lock *); 747 void (*fl_notify)(struct file_lock *); /* unblock callback */ 748 void (*fl_copy_lock)(struct file_lock *, struct file_lock *); 749 void (*fl_release_private)(struct file_lock *); 750 void (*fl_break)(struct file_lock *); 751 int (*fl_mylease)(struct file_lock *, struct file_lock *); 752 int (*fl_change)(struct file_lock **, int); 753 }; 754 755 /* that will die - we need it for nfs_lock_info */ 756 #include <linux/nfs_fs_i.h> 757 758 struct file_lock { 759 struct file_lock *fl_next; /* singly linked list for this inode */ 760 struct list_head fl_link; /* doubly linked list of all locks */ 761 struct list_head fl_block; /* circular list of blocked processes */ 762 fl_owner_t fl_owner; 763 unsigned int fl_pid; 764 wait_queue_head_t fl_wait; 765 struct file *fl_file; 766 unsigned char fl_flags; 767 unsigned char fl_type; 768 loff_t fl_start; 769 loff_t fl_end; 770 771 struct fasync_struct * fl_fasync; /* for lease break notifications */ 772 unsigned long fl_break_time; /* for nonblocking lease breaks */ 773 774 struct file_lock_operations *fl_ops; /* Callbacks for filesystems */ 775 struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */ 776 union { 777 struct nfs_lock_info nfs_fl; 778 struct nfs4_lock_info nfs4_fl; 779 } fl_u; 780 }; 781 782 /* The following constant reflects the upper bound of the file/locking space */ 783 #ifndef OFFSET_MAX 784 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1))) 785 #define OFFSET_MAX INT_LIMIT(loff_t) 786 #define OFFT_OFFSET_MAX INT_LIMIT(off_t) 787 #endif 788 789 #include <linux/fcntl.h> 790 791 extern int fcntl_getlk(struct file *, struct flock __user *); 792 extern int fcntl_setlk(unsigned int, struct file *, unsigned int, 793 struct flock __user *); 794 795 #if BITS_PER_LONG == 32 796 extern int fcntl_getlk64(struct file *, struct flock64 __user *); 797 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int, 798 struct flock64 __user *); 799 #endif 800 801 extern void send_sigio(struct fown_struct *fown, int fd, int band); 802 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg); 803 extern int fcntl_getlease(struct file *filp); 804 805 /* fs/sync.c */ 806 extern int do_sync_file_range(struct file *file, loff_t offset, loff_t endbyte, 807 unsigned int flags); 808 809 /* fs/locks.c */ 810 extern void locks_init_lock(struct file_lock *); 811 extern void locks_copy_lock(struct file_lock *, struct file_lock *); 812 extern void locks_remove_posix(struct file *, fl_owner_t); 813 extern void locks_remove_flock(struct file *); 814 extern int posix_test_lock(struct file *, struct file_lock *, struct file_lock *); 815 extern int posix_lock_file_conf(struct file *, struct file_lock *, struct file_lock *); 816 extern int posix_lock_file(struct file *, struct file_lock *); 817 extern int posix_lock_file_wait(struct file *, struct file_lock *); 818 extern int posix_unblock_lock(struct file *, struct file_lock *); 819 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl); 820 extern int __break_lease(struct inode *inode, unsigned int flags); 821 extern void lease_get_mtime(struct inode *, struct timespec *time); 822 extern int setlease(struct file *, long, struct file_lock **); 823 extern int lease_modify(struct file_lock **, int); 824 extern int lock_may_read(struct inode *, loff_t start, unsigned long count); 825 extern int lock_may_write(struct inode *, loff_t start, unsigned long count); 826 827 struct fasync_struct { 828 int magic; 829 int fa_fd; 830 struct fasync_struct *fa_next; /* singly linked list */ 831 struct file *fa_file; 832 }; 833 834 #define FASYNC_MAGIC 0x4601 835 836 /* SMP safe fasync helpers: */ 837 extern int fasync_helper(int, struct file *, int, struct fasync_struct **); 838 /* can be called from interrupts */ 839 extern void kill_fasync(struct fasync_struct **, int, int); 840 /* only for net: no internal synchronization */ 841 extern void __kill_fasync(struct fasync_struct *, int, int); 842 843 extern int f_setown(struct file *filp, unsigned long arg, int force); 844 extern void f_delown(struct file *filp); 845 extern int send_sigurg(struct fown_struct *fown); 846 847 /* 848 * Umount options 849 */ 850 851 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */ 852 #define MNT_DETACH 0x00000002 /* Just detach from the tree */ 853 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */ 854 855 extern struct list_head super_blocks; 856 extern spinlock_t sb_lock; 857 858 #define sb_entry(list) list_entry((list), struct super_block, s_list) 859 #define S_BIAS (1<<30) 860 struct super_block { 861 struct list_head s_list; /* Keep this first */ 862 dev_t s_dev; /* search index; _not_ kdev_t */ 863 unsigned long s_blocksize; 864 unsigned char s_blocksize_bits; 865 unsigned char s_dirt; 866 unsigned long long s_maxbytes; /* Max file size */ 867 struct file_system_type *s_type; 868 struct super_operations *s_op; 869 struct dquot_operations *dq_op; 870 struct quotactl_ops *s_qcop; 871 struct export_operations *s_export_op; 872 unsigned long s_flags; 873 unsigned long s_magic; 874 struct dentry *s_root; 875 struct rw_semaphore s_umount; 876 struct mutex s_lock; 877 int s_count; 878 int s_syncing; 879 int s_need_sync_fs; 880 atomic_t s_active; 881 void *s_security; 882 struct xattr_handler **s_xattr; 883 884 struct list_head s_inodes; /* all inodes */ 885 struct list_head s_dirty; /* dirty inodes */ 886 struct list_head s_io; /* parked for writeback */ 887 struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */ 888 struct list_head s_files; 889 890 struct block_device *s_bdev; 891 struct list_head s_instances; 892 struct quota_info s_dquot; /* Diskquota specific options */ 893 894 int s_frozen; 895 wait_queue_head_t s_wait_unfrozen; 896 897 char s_id[32]; /* Informational name */ 898 899 void *s_fs_info; /* Filesystem private info */ 900 901 /* 902 * The next field is for VFS *only*. No filesystems have any business 903 * even looking at it. You had been warned. 904 */ 905 struct mutex s_vfs_rename_mutex; /* Kludge */ 906 907 /* Granularity of c/m/atime in ns. 908 Cannot be worse than a second */ 909 u32 s_time_gran; 910 }; 911 912 extern struct timespec current_fs_time(struct super_block *sb); 913 914 /* 915 * Snapshotting support. 916 */ 917 enum { 918 SB_UNFROZEN = 0, 919 SB_FREEZE_WRITE = 1, 920 SB_FREEZE_TRANS = 2, 921 }; 922 923 #define vfs_check_frozen(sb, level) \ 924 wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level))) 925 926 static inline void get_fs_excl(void) 927 { 928 atomic_inc(¤t->fs_excl); 929 } 930 931 static inline void put_fs_excl(void) 932 { 933 atomic_dec(¤t->fs_excl); 934 } 935 936 static inline int has_fs_excl(void) 937 { 938 return atomic_read(¤t->fs_excl); 939 } 940 941 942 /* 943 * Superblock locking. 944 */ 945 static inline void lock_super(struct super_block * sb) 946 { 947 get_fs_excl(); 948 mutex_lock(&sb->s_lock); 949 } 950 951 static inline void unlock_super(struct super_block * sb) 952 { 953 put_fs_excl(); 954 mutex_unlock(&sb->s_lock); 955 } 956 957 /* 958 * VFS helper functions.. 959 */ 960 extern int vfs_permission(struct nameidata *, int); 961 extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *); 962 extern int vfs_mkdir(struct inode *, struct dentry *, int); 963 extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t); 964 extern int vfs_symlink(struct inode *, struct dentry *, const char *, int); 965 extern int vfs_link(struct dentry *, struct inode *, struct dentry *); 966 extern int vfs_rmdir(struct inode *, struct dentry *); 967 extern int vfs_unlink(struct inode *, struct dentry *); 968 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); 969 970 /* 971 * VFS dentry helper functions. 972 */ 973 extern void dentry_unhash(struct dentry *dentry); 974 975 /* 976 * VFS file helper functions. 977 */ 978 extern int file_permission(struct file *, int); 979 980 /* 981 * File types 982 * 983 * NOTE! These match bits 12..15 of stat.st_mode 984 * (ie "(i_mode >> 12) & 15"). 985 */ 986 #define DT_UNKNOWN 0 987 #define DT_FIFO 1 988 #define DT_CHR 2 989 #define DT_DIR 4 990 #define DT_BLK 6 991 #define DT_REG 8 992 #define DT_LNK 10 993 #define DT_SOCK 12 994 #define DT_WHT 14 995 996 #define OSYNC_METADATA (1<<0) 997 #define OSYNC_DATA (1<<1) 998 #define OSYNC_INODE (1<<2) 999 int generic_osync_inode(struct inode *, struct address_space *, int); 1000 1001 /* 1002 * This is the "filldir" function type, used by readdir() to let 1003 * the kernel specify what kind of dirent layout it wants to have. 1004 * This allows the kernel to read directories into kernel space or 1005 * to have different dirent layouts depending on the binary type. 1006 */ 1007 typedef int (*filldir_t)(void *, const char *, int, loff_t, ino_t, unsigned); 1008 1009 struct block_device_operations { 1010 int (*open) (struct inode *, struct file *); 1011 int (*release) (struct inode *, struct file *); 1012 int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long); 1013 long (*unlocked_ioctl) (struct file *, unsigned, unsigned long); 1014 long (*compat_ioctl) (struct file *, unsigned, unsigned long); 1015 int (*direct_access) (struct block_device *, sector_t, unsigned long *); 1016 int (*media_changed) (struct gendisk *); 1017 int (*revalidate_disk) (struct gendisk *); 1018 int (*getgeo)(struct block_device *, struct hd_geometry *); 1019 struct module *owner; 1020 }; 1021 1022 /* 1023 * "descriptor" for what we're up to with a read for sendfile(). 1024 * This allows us to use the same read code yet 1025 * have multiple different users of the data that 1026 * we read from a file. 1027 * 1028 * The simplest case just copies the data to user 1029 * mode. 1030 */ 1031 typedef struct { 1032 size_t written; 1033 size_t count; 1034 union { 1035 char __user * buf; 1036 void *data; 1037 } arg; 1038 int error; 1039 } read_descriptor_t; 1040 1041 typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long); 1042 1043 /* These macros are for out of kernel modules to test that 1044 * the kernel supports the unlocked_ioctl and compat_ioctl 1045 * fields in struct file_operations. */ 1046 #define HAVE_COMPAT_IOCTL 1 1047 #define HAVE_UNLOCKED_IOCTL 1 1048 1049 /* 1050 * NOTE: 1051 * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl 1052 * can be called without the big kernel lock held in all filesystems. 1053 */ 1054 struct file_operations { 1055 struct module *owner; 1056 loff_t (*llseek) (struct file *, loff_t, int); 1057 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); 1058 ssize_t (*aio_read) (struct kiocb *, char __user *, size_t, loff_t); 1059 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); 1060 ssize_t (*aio_write) (struct kiocb *, const char __user *, size_t, loff_t); 1061 int (*readdir) (struct file *, void *, filldir_t); 1062 unsigned int (*poll) (struct file *, struct poll_table_struct *); 1063 int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long); 1064 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); 1065 long (*compat_ioctl) (struct file *, unsigned int, unsigned long); 1066 int (*mmap) (struct file *, struct vm_area_struct *); 1067 int (*open) (struct inode *, struct file *); 1068 int (*flush) (struct file *, fl_owner_t id); 1069 int (*release) (struct inode *, struct file *); 1070 int (*fsync) (struct file *, struct dentry *, int datasync); 1071 int (*aio_fsync) (struct kiocb *, int datasync); 1072 int (*fasync) (int, struct file *, int); 1073 int (*lock) (struct file *, int, struct file_lock *); 1074 ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *); 1075 ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *); 1076 ssize_t (*sendfile) (struct file *, loff_t *, size_t, read_actor_t, void *); 1077 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int); 1078 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); 1079 int (*check_flags)(int); 1080 int (*dir_notify)(struct file *filp, unsigned long arg); 1081 int (*flock) (struct file *, int, struct file_lock *); 1082 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int); 1083 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int); 1084 }; 1085 1086 struct inode_operations { 1087 int (*create) (struct inode *,struct dentry *,int, struct nameidata *); 1088 struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *); 1089 int (*link) (struct dentry *,struct inode *,struct dentry *); 1090 int (*unlink) (struct inode *,struct dentry *); 1091 int (*symlink) (struct inode *,struct dentry *,const char *); 1092 int (*mkdir) (struct inode *,struct dentry *,int); 1093 int (*rmdir) (struct inode *,struct dentry *); 1094 int (*mknod) (struct inode *,struct dentry *,int,dev_t); 1095 int (*rename) (struct inode *, struct dentry *, 1096 struct inode *, struct dentry *); 1097 int (*readlink) (struct dentry *, char __user *,int); 1098 void * (*follow_link) (struct dentry *, struct nameidata *); 1099 void (*put_link) (struct dentry *, struct nameidata *, void *); 1100 void (*truncate) (struct inode *); 1101 int (*permission) (struct inode *, int, struct nameidata *); 1102 int (*setattr) (struct dentry *, struct iattr *); 1103 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *); 1104 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int); 1105 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t); 1106 ssize_t (*listxattr) (struct dentry *, char *, size_t); 1107 int (*removexattr) (struct dentry *, const char *); 1108 void (*truncate_range)(struct inode *, loff_t, loff_t); 1109 }; 1110 1111 struct seq_file; 1112 1113 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *); 1114 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *); 1115 extern ssize_t vfs_readv(struct file *, const struct iovec __user *, 1116 unsigned long, loff_t *); 1117 extern ssize_t vfs_writev(struct file *, const struct iovec __user *, 1118 unsigned long, loff_t *); 1119 1120 /* 1121 * NOTE: write_inode, delete_inode, clear_inode, put_inode can be called 1122 * without the big kernel lock held in all filesystems. 1123 */ 1124 struct super_operations { 1125 struct inode *(*alloc_inode)(struct super_block *sb); 1126 void (*destroy_inode)(struct inode *); 1127 1128 void (*read_inode) (struct inode *); 1129 1130 void (*dirty_inode) (struct inode *); 1131 int (*write_inode) (struct inode *, int); 1132 void (*put_inode) (struct inode *); 1133 void (*drop_inode) (struct inode *); 1134 void (*delete_inode) (struct inode *); 1135 void (*put_super) (struct super_block *); 1136 void (*write_super) (struct super_block *); 1137 int (*sync_fs)(struct super_block *sb, int wait); 1138 void (*write_super_lockfs) (struct super_block *); 1139 void (*unlockfs) (struct super_block *); 1140 int (*statfs) (struct dentry *, struct kstatfs *); 1141 int (*remount_fs) (struct super_block *, int *, char *); 1142 void (*clear_inode) (struct inode *); 1143 void (*umount_begin) (struct vfsmount *, int); 1144 1145 int (*show_options)(struct seq_file *, struct vfsmount *); 1146 int (*show_stats)(struct seq_file *, struct vfsmount *); 1147 1148 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t); 1149 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t); 1150 }; 1151 1152 /* Inode state bits. Protected by inode_lock. */ 1153 #define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */ 1154 #define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */ 1155 #define I_DIRTY_PAGES 4 /* Data-related inode changes pending */ 1156 #define __I_LOCK 3 1157 #define I_LOCK (1 << __I_LOCK) 1158 #define I_FREEING 16 1159 #define I_CLEAR 32 1160 #define I_NEW 64 1161 #define I_WILL_FREE 128 1162 1163 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES) 1164 1165 extern void __mark_inode_dirty(struct inode *, int); 1166 static inline void mark_inode_dirty(struct inode *inode) 1167 { 1168 __mark_inode_dirty(inode, I_DIRTY); 1169 } 1170 1171 static inline void mark_inode_dirty_sync(struct inode *inode) 1172 { 1173 __mark_inode_dirty(inode, I_DIRTY_SYNC); 1174 } 1175 1176 static inline void inode_inc_link_count(struct inode *inode) 1177 { 1178 inode->i_nlink++; 1179 mark_inode_dirty(inode); 1180 } 1181 1182 static inline void inode_dec_link_count(struct inode *inode) 1183 { 1184 inode->i_nlink--; 1185 mark_inode_dirty(inode); 1186 } 1187 1188 extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry); 1189 static inline void file_accessed(struct file *file) 1190 { 1191 if (!(file->f_flags & O_NOATIME)) 1192 touch_atime(file->f_vfsmnt, file->f_dentry); 1193 } 1194 1195 int sync_inode(struct inode *inode, struct writeback_control *wbc); 1196 1197 /** 1198 * struct export_operations - for nfsd to communicate with file systems 1199 * @decode_fh: decode a file handle fragment and return a &struct dentry 1200 * @encode_fh: encode a file handle fragment from a dentry 1201 * @get_name: find the name for a given inode in a given directory 1202 * @get_parent: find the parent of a given directory 1203 * @get_dentry: find a dentry for the inode given a file handle sub-fragment 1204 * @find_exported_dentry: 1205 * set by the exporting module to a standard helper function. 1206 * 1207 * Description: 1208 * The export_operations structure provides a means for nfsd to communicate 1209 * with a particular exported file system - particularly enabling nfsd and 1210 * the filesystem to co-operate when dealing with file handles. 1211 * 1212 * export_operations contains two basic operation for dealing with file 1213 * handles, decode_fh() and encode_fh(), and allows for some other 1214 * operations to be defined which standard helper routines use to get 1215 * specific information from the filesystem. 1216 * 1217 * nfsd encodes information use to determine which filesystem a filehandle 1218 * applies to in the initial part of the file handle. The remainder, termed 1219 * a file handle fragment, is controlled completely by the filesystem. The 1220 * standard helper routines assume that this fragment will contain one or 1221 * two sub-fragments, one which identifies the file, and one which may be 1222 * used to identify the (a) directory containing the file. 1223 * 1224 * In some situations, nfsd needs to get a dentry which is connected into a 1225 * specific part of the file tree. To allow for this, it passes the 1226 * function acceptable() together with a @context which can be used to see 1227 * if the dentry is acceptable. As there can be multiple dentrys for a 1228 * given file, the filesystem should check each one for acceptability before 1229 * looking for the next. As soon as an acceptable one is found, it should 1230 * be returned. 1231 * 1232 * decode_fh: 1233 * @decode_fh is given a &struct super_block (@sb), a file handle fragment 1234 * (@fh, @fh_len) and an acceptability testing function (@acceptable, 1235 * @context). It should return a &struct dentry which refers to the same 1236 * file that the file handle fragment refers to, and which passes the 1237 * acceptability test. If it cannot, it should return a %NULL pointer if 1238 * the file was found but no acceptable &dentries were available, or a 1239 * %ERR_PTR error code indicating why it couldn't be found (e.g. %ENOENT or 1240 * %ENOMEM). 1241 * 1242 * encode_fh: 1243 * @encode_fh should store in the file handle fragment @fh (using at most 1244 * @max_len bytes) information that can be used by @decode_fh to recover the 1245 * file refered to by the &struct dentry @de. If the @connectable flag is 1246 * set, the encode_fh() should store sufficient information so that a good 1247 * attempt can be made to find not only the file but also it's place in the 1248 * filesystem. This typically means storing a reference to de->d_parent in 1249 * the filehandle fragment. encode_fh() should return the number of bytes 1250 * stored or a negative error code such as %-ENOSPC 1251 * 1252 * get_name: 1253 * @get_name should find a name for the given @child in the given @parent 1254 * directory. The name should be stored in the @name (with the 1255 * understanding that it is already pointing to a a %NAME_MAX+1 sized 1256 * buffer. get_name() should return %0 on success, a negative error code 1257 * or error. @get_name will be called without @parent->i_mutex held. 1258 * 1259 * get_parent: 1260 * @get_parent should find the parent directory for the given @child which 1261 * is also a directory. In the event that it cannot be found, or storage 1262 * space cannot be allocated, a %ERR_PTR should be returned. 1263 * 1264 * get_dentry: 1265 * Given a &super_block (@sb) and a pointer to a file-system specific inode 1266 * identifier, possibly an inode number, (@inump) get_dentry() should find 1267 * the identified inode and return a dentry for that inode. Any suitable 1268 * dentry can be returned including, if necessary, a new dentry created with 1269 * d_alloc_root. The caller can then find any other extant dentrys by 1270 * following the d_alias links. If a new dentry was created using 1271 * d_alloc_root, DCACHE_NFSD_DISCONNECTED should be set, and the dentry 1272 * should be d_rehash()ed. 1273 * 1274 * If the inode cannot be found, either a %NULL pointer or an %ERR_PTR code 1275 * can be returned. The @inump will be whatever was passed to 1276 * nfsd_find_fh_dentry() in either the @obj or @parent parameters. 1277 * 1278 * Locking rules: 1279 * get_parent is called with child->d_inode->i_mutex down 1280 * get_name is not (which is possibly inconsistent) 1281 */ 1282 1283 struct export_operations { 1284 struct dentry *(*decode_fh)(struct super_block *sb, __u32 *fh, int fh_len, int fh_type, 1285 int (*acceptable)(void *context, struct dentry *de), 1286 void *context); 1287 int (*encode_fh)(struct dentry *de, __u32 *fh, int *max_len, 1288 int connectable); 1289 1290 /* the following are only called from the filesystem itself */ 1291 int (*get_name)(struct dentry *parent, char *name, 1292 struct dentry *child); 1293 struct dentry * (*get_parent)(struct dentry *child); 1294 struct dentry * (*get_dentry)(struct super_block *sb, void *inump); 1295 1296 /* This is set by the exporting module to a standard helper */ 1297 struct dentry * (*find_exported_dentry)( 1298 struct super_block *sb, void *obj, void *parent, 1299 int (*acceptable)(void *context, struct dentry *de), 1300 void *context); 1301 1302 1303 }; 1304 1305 extern struct dentry * 1306 find_exported_dentry(struct super_block *sb, void *obj, void *parent, 1307 int (*acceptable)(void *context, struct dentry *de), 1308 void *context); 1309 1310 struct file_system_type { 1311 const char *name; 1312 int fs_flags; 1313 int (*get_sb) (struct file_system_type *, int, 1314 const char *, void *, struct vfsmount *); 1315 void (*kill_sb) (struct super_block *); 1316 struct module *owner; 1317 struct file_system_type * next; 1318 struct list_head fs_supers; 1319 struct lock_class_key s_lock_key; 1320 struct lock_class_key s_umount_key; 1321 }; 1322 1323 extern int get_sb_bdev(struct file_system_type *fs_type, 1324 int flags, const char *dev_name, void *data, 1325 int (*fill_super)(struct super_block *, void *, int), 1326 struct vfsmount *mnt); 1327 extern int get_sb_single(struct file_system_type *fs_type, 1328 int flags, void *data, 1329 int (*fill_super)(struct super_block *, void *, int), 1330 struct vfsmount *mnt); 1331 extern int get_sb_nodev(struct file_system_type *fs_type, 1332 int flags, void *data, 1333 int (*fill_super)(struct super_block *, void *, int), 1334 struct vfsmount *mnt); 1335 void generic_shutdown_super(struct super_block *sb); 1336 void kill_block_super(struct super_block *sb); 1337 void kill_anon_super(struct super_block *sb); 1338 void kill_litter_super(struct super_block *sb); 1339 void deactivate_super(struct super_block *sb); 1340 int set_anon_super(struct super_block *s, void *data); 1341 struct super_block *sget(struct file_system_type *type, 1342 int (*test)(struct super_block *,void *), 1343 int (*set)(struct super_block *,void *), 1344 void *data); 1345 extern int get_sb_pseudo(struct file_system_type *, char *, 1346 struct super_operations *ops, unsigned long, 1347 struct vfsmount *mnt); 1348 extern int simple_set_mnt(struct vfsmount *mnt, struct super_block *sb); 1349 int __put_super(struct super_block *sb); 1350 int __put_super_and_need_restart(struct super_block *sb); 1351 void unnamed_dev_init(void); 1352 1353 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */ 1354 #define fops_get(fops) \ 1355 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL)) 1356 #define fops_put(fops) \ 1357 do { if (fops) module_put((fops)->owner); } while(0) 1358 1359 extern int register_filesystem(struct file_system_type *); 1360 extern int unregister_filesystem(struct file_system_type *); 1361 extern struct vfsmount *kern_mount(struct file_system_type *); 1362 extern int may_umount_tree(struct vfsmount *); 1363 extern int may_umount(struct vfsmount *); 1364 extern void umount_tree(struct vfsmount *, int, struct list_head *); 1365 extern void release_mounts(struct list_head *); 1366 extern long do_mount(char *, char *, char *, unsigned long, void *); 1367 extern struct vfsmount *copy_tree(struct vfsmount *, struct dentry *, int); 1368 extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *, 1369 struct vfsmount *); 1370 1371 extern int vfs_statfs(struct dentry *, struct kstatfs *); 1372 1373 /* /sys/fs */ 1374 extern struct subsystem fs_subsys; 1375 1376 #define FLOCK_VERIFY_READ 1 1377 #define FLOCK_VERIFY_WRITE 2 1378 1379 extern int locks_mandatory_locked(struct inode *); 1380 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t); 1381 1382 /* 1383 * Candidates for mandatory locking have the setgid bit set 1384 * but no group execute bit - an otherwise meaningless combination. 1385 */ 1386 #define MANDATORY_LOCK(inode) \ 1387 (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID) 1388 1389 static inline int locks_verify_locked(struct inode *inode) 1390 { 1391 if (MANDATORY_LOCK(inode)) 1392 return locks_mandatory_locked(inode); 1393 return 0; 1394 } 1395 1396 extern int rw_verify_area(int, struct file *, loff_t *, size_t); 1397 1398 static inline int locks_verify_truncate(struct inode *inode, 1399 struct file *filp, 1400 loff_t size) 1401 { 1402 if (inode->i_flock && MANDATORY_LOCK(inode)) 1403 return locks_mandatory_area( 1404 FLOCK_VERIFY_WRITE, inode, filp, 1405 size < inode->i_size ? size : inode->i_size, 1406 (size < inode->i_size ? inode->i_size - size 1407 : size - inode->i_size) 1408 ); 1409 return 0; 1410 } 1411 1412 static inline int break_lease(struct inode *inode, unsigned int mode) 1413 { 1414 if (inode->i_flock) 1415 return __break_lease(inode, mode); 1416 return 0; 1417 } 1418 1419 /* fs/open.c */ 1420 1421 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs, 1422 struct file *filp); 1423 extern long do_sys_open(int fdf, const char __user *filename, int flags, 1424 int mode); 1425 extern struct file *filp_open(const char *, int, int); 1426 extern struct file * dentry_open(struct dentry *, struct vfsmount *, int); 1427 extern int filp_close(struct file *, fl_owner_t id); 1428 extern char * getname(const char __user *); 1429 1430 /* fs/dcache.c */ 1431 extern void __init vfs_caches_init_early(void); 1432 extern void __init vfs_caches_init(unsigned long); 1433 1434 #define __getname() kmem_cache_alloc(names_cachep, SLAB_KERNEL) 1435 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name)) 1436 #ifndef CONFIG_AUDITSYSCALL 1437 #define putname(name) __putname(name) 1438 #else 1439 extern void putname(const char *name); 1440 #endif 1441 1442 extern int register_blkdev(unsigned int, const char *); 1443 extern int unregister_blkdev(unsigned int, const char *); 1444 extern struct block_device *bdget(dev_t); 1445 extern void bd_set_size(struct block_device *, loff_t size); 1446 extern void bd_forget(struct inode *inode); 1447 extern void bdput(struct block_device *); 1448 extern struct block_device *open_by_devnum(dev_t, unsigned); 1449 extern struct block_device *open_partition_by_devnum(dev_t, unsigned); 1450 extern const struct file_operations def_blk_fops; 1451 extern const struct address_space_operations def_blk_aops; 1452 extern const struct file_operations def_chr_fops; 1453 extern const struct file_operations bad_sock_fops; 1454 extern const struct file_operations def_fifo_fops; 1455 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long); 1456 extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long); 1457 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long); 1458 extern int blkdev_get(struct block_device *, mode_t, unsigned); 1459 extern int blkdev_put(struct block_device *); 1460 extern int blkdev_put_partition(struct block_device *); 1461 extern int bd_claim(struct block_device *, void *); 1462 extern void bd_release(struct block_device *); 1463 #ifdef CONFIG_SYSFS 1464 extern int bd_claim_by_disk(struct block_device *, void *, struct gendisk *); 1465 extern void bd_release_from_disk(struct block_device *, struct gendisk *); 1466 #else 1467 #define bd_claim_by_disk(bdev, holder, disk) bd_claim(bdev, holder) 1468 #define bd_release_from_disk(bdev, disk) bd_release(bdev) 1469 #endif 1470 1471 /* fs/char_dev.c */ 1472 #define CHRDEV_MAJOR_HASH_SIZE 255 1473 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *); 1474 extern int register_chrdev_region(dev_t, unsigned, const char *); 1475 extern int register_chrdev(unsigned int, const char *, 1476 const struct file_operations *); 1477 extern int unregister_chrdev(unsigned int, const char *); 1478 extern void unregister_chrdev_region(dev_t, unsigned); 1479 extern int chrdev_open(struct inode *, struct file *); 1480 extern void chrdev_show(struct seq_file *,off_t); 1481 1482 /* fs/block_dev.c */ 1483 #define BLKDEV_MAJOR_HASH_SIZE 255 1484 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */ 1485 extern const char *__bdevname(dev_t, char *buffer); 1486 extern const char *bdevname(struct block_device *bdev, char *buffer); 1487 extern struct block_device *lookup_bdev(const char *); 1488 extern struct block_device *open_bdev_excl(const char *, int, void *); 1489 extern void close_bdev_excl(struct block_device *); 1490 extern void blkdev_show(struct seq_file *,off_t); 1491 1492 extern void init_special_inode(struct inode *, umode_t, dev_t); 1493 1494 /* Invalid inode operations -- fs/bad_inode.c */ 1495 extern void make_bad_inode(struct inode *); 1496 extern int is_bad_inode(struct inode *); 1497 1498 extern const struct file_operations read_fifo_fops; 1499 extern const struct file_operations write_fifo_fops; 1500 extern const struct file_operations rdwr_fifo_fops; 1501 1502 extern int fs_may_remount_ro(struct super_block *); 1503 1504 /* 1505 * return READ, READA, or WRITE 1506 */ 1507 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK)) 1508 1509 /* 1510 * return data direction, READ or WRITE 1511 */ 1512 #define bio_data_dir(bio) ((bio)->bi_rw & 1) 1513 1514 extern int check_disk_change(struct block_device *); 1515 extern int invalidate_inodes(struct super_block *); 1516 extern int __invalidate_device(struct block_device *); 1517 extern int invalidate_partition(struct gendisk *, int); 1518 unsigned long invalidate_mapping_pages(struct address_space *mapping, 1519 pgoff_t start, pgoff_t end); 1520 unsigned long invalidate_inode_pages(struct address_space *mapping); 1521 static inline void invalidate_remote_inode(struct inode *inode) 1522 { 1523 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || 1524 S_ISLNK(inode->i_mode)) 1525 invalidate_inode_pages(inode->i_mapping); 1526 } 1527 extern int invalidate_inode_pages2(struct address_space *mapping); 1528 extern int invalidate_inode_pages2_range(struct address_space *mapping, 1529 pgoff_t start, pgoff_t end); 1530 extern int write_inode_now(struct inode *, int); 1531 extern int filemap_fdatawrite(struct address_space *); 1532 extern int filemap_flush(struct address_space *); 1533 extern int filemap_fdatawait(struct address_space *); 1534 extern int filemap_write_and_wait(struct address_space *mapping); 1535 extern int filemap_write_and_wait_range(struct address_space *mapping, 1536 loff_t lstart, loff_t lend); 1537 extern int wait_on_page_writeback_range(struct address_space *mapping, 1538 pgoff_t start, pgoff_t end); 1539 extern int __filemap_fdatawrite_range(struct address_space *mapping, 1540 loff_t start, loff_t end, int sync_mode); 1541 1542 extern long do_fsync(struct file *file, int datasync); 1543 extern void sync_supers(void); 1544 extern void sync_filesystems(int wait); 1545 extern void emergency_sync(void); 1546 extern void emergency_remount(void); 1547 extern int do_remount_sb(struct super_block *sb, int flags, 1548 void *data, int force); 1549 extern sector_t bmap(struct inode *, sector_t); 1550 extern int notify_change(struct dentry *, struct iattr *); 1551 extern int permission(struct inode *, int, struct nameidata *); 1552 extern int generic_permission(struct inode *, int, 1553 int (*check_acl)(struct inode *, int)); 1554 1555 extern int get_write_access(struct inode *); 1556 extern int deny_write_access(struct file *); 1557 static inline void put_write_access(struct inode * inode) 1558 { 1559 atomic_dec(&inode->i_writecount); 1560 } 1561 static inline void allow_write_access(struct file *file) 1562 { 1563 if (file) 1564 atomic_inc(&file->f_dentry->d_inode->i_writecount); 1565 } 1566 extern int do_pipe(int *); 1567 1568 extern int open_namei(int dfd, const char *, int, int, struct nameidata *); 1569 extern int may_open(struct nameidata *, int, int); 1570 1571 extern int kernel_read(struct file *, unsigned long, char *, unsigned long); 1572 extern struct file * open_exec(const char *); 1573 1574 /* fs/dcache.c -- generic fs support functions */ 1575 extern int is_subdir(struct dentry *, struct dentry *); 1576 extern ino_t find_inode_number(struct dentry *, struct qstr *); 1577 1578 #include <linux/err.h> 1579 1580 /* needed for stackable file system support */ 1581 extern loff_t default_llseek(struct file *file, loff_t offset, int origin); 1582 1583 extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin); 1584 1585 extern void inode_init_once(struct inode *); 1586 extern void iput(struct inode *); 1587 extern struct inode * igrab(struct inode *); 1588 extern ino_t iunique(struct super_block *, ino_t); 1589 extern int inode_needs_sync(struct inode *inode); 1590 extern void generic_delete_inode(struct inode *inode); 1591 extern void generic_drop_inode(struct inode *inode); 1592 1593 extern struct inode *ilookup5_nowait(struct super_block *sb, 1594 unsigned long hashval, int (*test)(struct inode *, void *), 1595 void *data); 1596 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval, 1597 int (*test)(struct inode *, void *), void *data); 1598 extern struct inode *ilookup(struct super_block *sb, unsigned long ino); 1599 1600 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *); 1601 extern struct inode * iget_locked(struct super_block *, unsigned long); 1602 extern void unlock_new_inode(struct inode *); 1603 1604 static inline struct inode *iget(struct super_block *sb, unsigned long ino) 1605 { 1606 struct inode *inode = iget_locked(sb, ino); 1607 1608 if (inode && (inode->i_state & I_NEW)) { 1609 sb->s_op->read_inode(inode); 1610 unlock_new_inode(inode); 1611 } 1612 1613 return inode; 1614 } 1615 1616 extern void __iget(struct inode * inode); 1617 extern void clear_inode(struct inode *); 1618 extern void destroy_inode(struct inode *); 1619 extern struct inode *new_inode(struct super_block *); 1620 extern int remove_suid(struct dentry *); 1621 extern void remove_dquot_ref(struct super_block *, int, struct list_head *); 1622 1623 extern void __insert_inode_hash(struct inode *, unsigned long hashval); 1624 extern void remove_inode_hash(struct inode *); 1625 static inline void insert_inode_hash(struct inode *inode) { 1626 __insert_inode_hash(inode, inode->i_ino); 1627 } 1628 1629 extern struct file * get_empty_filp(void); 1630 extern void file_move(struct file *f, struct list_head *list); 1631 extern void file_kill(struct file *f); 1632 struct bio; 1633 extern void submit_bio(int, struct bio *); 1634 extern int bdev_read_only(struct block_device *); 1635 extern int set_blocksize(struct block_device *, int); 1636 extern int sb_set_blocksize(struct super_block *, int); 1637 extern int sb_min_blocksize(struct super_block *, int); 1638 1639 extern int generic_file_mmap(struct file *, struct vm_area_struct *); 1640 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *); 1641 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size); 1642 extern int file_send_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size); 1643 extern ssize_t generic_file_read(struct file *, char __user *, size_t, loff_t *); 1644 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk); 1645 extern ssize_t generic_file_write(struct file *, const char __user *, size_t, loff_t *); 1646 extern ssize_t generic_file_aio_read(struct kiocb *, char __user *, size_t, loff_t); 1647 extern ssize_t __generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t *); 1648 extern ssize_t generic_file_aio_write(struct kiocb *, const char __user *, size_t, loff_t); 1649 extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *, 1650 unsigned long, loff_t *); 1651 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *, 1652 unsigned long *, loff_t, loff_t *, size_t, size_t); 1653 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *, 1654 unsigned long, loff_t, loff_t *, size_t, ssize_t); 1655 extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos); 1656 extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos); 1657 ssize_t generic_file_write_nolock(struct file *file, const struct iovec *iov, 1658 unsigned long nr_segs, loff_t *ppos); 1659 extern ssize_t generic_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *); 1660 extern void do_generic_mapping_read(struct address_space *mapping, 1661 struct file_ra_state *, struct file *, 1662 loff_t *, read_descriptor_t *, read_actor_t); 1663 1664 /* fs/splice.c */ 1665 extern ssize_t generic_file_splice_read(struct file *, loff_t *, 1666 struct pipe_inode_info *, size_t, unsigned int); 1667 extern ssize_t generic_file_splice_write(struct pipe_inode_info *, 1668 struct file *, loff_t *, size_t, unsigned int); 1669 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, 1670 struct file *out, loff_t *, size_t len, unsigned int flags); 1671 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out, 1672 size_t len, unsigned int flags); 1673 1674 extern void 1675 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping); 1676 extern ssize_t generic_file_readv(struct file *filp, const struct iovec *iov, 1677 unsigned long nr_segs, loff_t *ppos); 1678 ssize_t generic_file_writev(struct file *filp, const struct iovec *iov, 1679 unsigned long nr_segs, loff_t *ppos); 1680 extern loff_t no_llseek(struct file *file, loff_t offset, int origin); 1681 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin); 1682 extern loff_t remote_llseek(struct file *file, loff_t offset, int origin); 1683 extern int generic_file_open(struct inode * inode, struct file * filp); 1684 extern int nonseekable_open(struct inode * inode, struct file * filp); 1685 1686 #ifdef CONFIG_FS_XIP 1687 extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len, 1688 loff_t *ppos); 1689 extern ssize_t xip_file_sendfile(struct file *in_file, loff_t *ppos, 1690 size_t count, read_actor_t actor, 1691 void *target); 1692 extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma); 1693 extern ssize_t xip_file_write(struct file *filp, const char __user *buf, 1694 size_t len, loff_t *ppos); 1695 extern int xip_truncate_page(struct address_space *mapping, loff_t from); 1696 #else 1697 static inline int xip_truncate_page(struct address_space *mapping, loff_t from) 1698 { 1699 return 0; 1700 } 1701 #endif 1702 1703 static inline void do_generic_file_read(struct file * filp, loff_t *ppos, 1704 read_descriptor_t * desc, 1705 read_actor_t actor) 1706 { 1707 do_generic_mapping_read(filp->f_mapping, 1708 &filp->f_ra, 1709 filp, 1710 ppos, 1711 desc, 1712 actor); 1713 } 1714 1715 ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, 1716 struct block_device *bdev, const struct iovec *iov, loff_t offset, 1717 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io, 1718 int lock_type); 1719 1720 enum { 1721 DIO_LOCKING = 1, /* need locking between buffered and direct access */ 1722 DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */ 1723 DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */ 1724 }; 1725 1726 static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb, 1727 struct inode *inode, struct block_device *bdev, const struct iovec *iov, 1728 loff_t offset, unsigned long nr_segs, get_block_t get_block, 1729 dio_iodone_t end_io) 1730 { 1731 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset, 1732 nr_segs, get_block, end_io, DIO_LOCKING); 1733 } 1734 1735 static inline ssize_t blockdev_direct_IO_no_locking(int rw, struct kiocb *iocb, 1736 struct inode *inode, struct block_device *bdev, const struct iovec *iov, 1737 loff_t offset, unsigned long nr_segs, get_block_t get_block, 1738 dio_iodone_t end_io) 1739 { 1740 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset, 1741 nr_segs, get_block, end_io, DIO_NO_LOCKING); 1742 } 1743 1744 static inline ssize_t blockdev_direct_IO_own_locking(int rw, struct kiocb *iocb, 1745 struct inode *inode, struct block_device *bdev, const struct iovec *iov, 1746 loff_t offset, unsigned long nr_segs, get_block_t get_block, 1747 dio_iodone_t end_io) 1748 { 1749 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset, 1750 nr_segs, get_block, end_io, DIO_OWN_LOCKING); 1751 } 1752 1753 extern const struct file_operations generic_ro_fops; 1754 1755 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m)) 1756 1757 extern int vfs_readlink(struct dentry *, char __user *, int, const char *); 1758 extern int vfs_follow_link(struct nameidata *, const char *); 1759 extern int page_readlink(struct dentry *, char __user *, int); 1760 extern void *page_follow_link_light(struct dentry *, struct nameidata *); 1761 extern void page_put_link(struct dentry *, struct nameidata *, void *); 1762 extern int __page_symlink(struct inode *inode, const char *symname, int len, 1763 gfp_t gfp_mask); 1764 extern int page_symlink(struct inode *inode, const char *symname, int len); 1765 extern struct inode_operations page_symlink_inode_operations; 1766 extern int generic_readlink(struct dentry *, char __user *, int); 1767 extern void generic_fillattr(struct inode *, struct kstat *); 1768 extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *); 1769 void inode_add_bytes(struct inode *inode, loff_t bytes); 1770 void inode_sub_bytes(struct inode *inode, loff_t bytes); 1771 loff_t inode_get_bytes(struct inode *inode); 1772 void inode_set_bytes(struct inode *inode, loff_t bytes); 1773 1774 extern int vfs_readdir(struct file *, filldir_t, void *); 1775 1776 extern int vfs_stat(char __user *, struct kstat *); 1777 extern int vfs_lstat(char __user *, struct kstat *); 1778 extern int vfs_stat_fd(int dfd, char __user *, struct kstat *); 1779 extern int vfs_lstat_fd(int dfd, char __user *, struct kstat *); 1780 extern int vfs_fstat(unsigned int, struct kstat *); 1781 1782 extern int vfs_ioctl(struct file *, unsigned int, unsigned int, unsigned long); 1783 1784 extern struct file_system_type *get_fs_type(const char *name); 1785 extern struct super_block *get_super(struct block_device *); 1786 extern struct super_block *user_get_super(dev_t); 1787 extern void drop_super(struct super_block *sb); 1788 1789 extern int dcache_dir_open(struct inode *, struct file *); 1790 extern int dcache_dir_close(struct inode *, struct file *); 1791 extern loff_t dcache_dir_lseek(struct file *, loff_t, int); 1792 extern int dcache_readdir(struct file *, void *, filldir_t); 1793 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *); 1794 extern int simple_statfs(struct dentry *, struct kstatfs *); 1795 extern int simple_link(struct dentry *, struct inode *, struct dentry *); 1796 extern int simple_unlink(struct inode *, struct dentry *); 1797 extern int simple_rmdir(struct inode *, struct dentry *); 1798 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); 1799 extern int simple_sync_file(struct file *, struct dentry *, int); 1800 extern int simple_empty(struct dentry *); 1801 extern int simple_readpage(struct file *file, struct page *page); 1802 extern int simple_prepare_write(struct file *file, struct page *page, 1803 unsigned offset, unsigned to); 1804 extern int simple_commit_write(struct file *file, struct page *page, 1805 unsigned offset, unsigned to); 1806 1807 extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *); 1808 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *); 1809 extern const struct file_operations simple_dir_operations; 1810 extern struct inode_operations simple_dir_inode_operations; 1811 struct tree_descr { char *name; const struct file_operations *ops; int mode; }; 1812 struct dentry *d_alloc_name(struct dentry *, const char *); 1813 extern int simple_fill_super(struct super_block *, int, struct tree_descr *); 1814 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count); 1815 extern void simple_release_fs(struct vfsmount **mount, int *count); 1816 1817 extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t); 1818 1819 #ifdef CONFIG_MIGRATION 1820 extern int buffer_migrate_page(struct address_space *, 1821 struct page *, struct page *); 1822 #else 1823 #define buffer_migrate_page NULL 1824 #endif 1825 1826 extern int inode_change_ok(struct inode *, struct iattr *); 1827 extern int __must_check inode_setattr(struct inode *, struct iattr *); 1828 1829 extern void file_update_time(struct file *file); 1830 1831 static inline ino_t parent_ino(struct dentry *dentry) 1832 { 1833 ino_t res; 1834 1835 spin_lock(&dentry->d_lock); 1836 res = dentry->d_parent->d_inode->i_ino; 1837 spin_unlock(&dentry->d_lock); 1838 return res; 1839 } 1840 1841 /* kernel/fork.c */ 1842 extern int unshare_files(void); 1843 1844 /* Transaction based IO helpers */ 1845 1846 /* 1847 * An argresp is stored in an allocated page and holds the 1848 * size of the argument or response, along with its content 1849 */ 1850 struct simple_transaction_argresp { 1851 ssize_t size; 1852 char data[0]; 1853 }; 1854 1855 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp)) 1856 1857 char *simple_transaction_get(struct file *file, const char __user *buf, 1858 size_t size); 1859 ssize_t simple_transaction_read(struct file *file, char __user *buf, 1860 size_t size, loff_t *pos); 1861 int simple_transaction_release(struct inode *inode, struct file *file); 1862 1863 static inline void simple_transaction_set(struct file *file, size_t n) 1864 { 1865 struct simple_transaction_argresp *ar = file->private_data; 1866 1867 BUG_ON(n > SIMPLE_TRANSACTION_LIMIT); 1868 1869 /* 1870 * The barrier ensures that ar->size will really remain zero until 1871 * ar->data is ready for reading. 1872 */ 1873 smp_mb(); 1874 ar->size = n; 1875 } 1876 1877 /* 1878 * simple attribute files 1879 * 1880 * These attributes behave similar to those in sysfs: 1881 * 1882 * Writing to an attribute immediately sets a value, an open file can be 1883 * written to multiple times. 1884 * 1885 * Reading from an attribute creates a buffer from the value that might get 1886 * read with multiple read calls. When the attribute has been read 1887 * completely, no further read calls are possible until the file is opened 1888 * again. 1889 * 1890 * All attributes contain a text representation of a numeric value 1891 * that are accessed with the get() and set() functions. 1892 */ 1893 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \ 1894 static int __fops ## _open(struct inode *inode, struct file *file) \ 1895 { \ 1896 __simple_attr_check_format(__fmt, 0ull); \ 1897 return simple_attr_open(inode, file, __get, __set, __fmt); \ 1898 } \ 1899 static struct file_operations __fops = { \ 1900 .owner = THIS_MODULE, \ 1901 .open = __fops ## _open, \ 1902 .release = simple_attr_close, \ 1903 .read = simple_attr_read, \ 1904 .write = simple_attr_write, \ 1905 }; 1906 1907 static inline void __attribute__((format(printf, 1, 2))) 1908 __simple_attr_check_format(const char *fmt, ...) 1909 { 1910 /* don't do anything, just let the compiler check the arguments; */ 1911 } 1912 1913 int simple_attr_open(struct inode *inode, struct file *file, 1914 u64 (*get)(void *), void (*set)(void *, u64), 1915 const char *fmt); 1916 int simple_attr_close(struct inode *inode, struct file *file); 1917 ssize_t simple_attr_read(struct file *file, char __user *buf, 1918 size_t len, loff_t *ppos); 1919 ssize_t simple_attr_write(struct file *file, const char __user *buf, 1920 size_t len, loff_t *ppos); 1921 1922 1923 #ifdef CONFIG_SECURITY 1924 static inline char *alloc_secdata(void) 1925 { 1926 return (char *)get_zeroed_page(GFP_KERNEL); 1927 } 1928 1929 static inline void free_secdata(void *secdata) 1930 { 1931 free_page((unsigned long)secdata); 1932 } 1933 #else 1934 static inline char *alloc_secdata(void) 1935 { 1936 return (char *)1; 1937 } 1938 1939 static inline void free_secdata(void *secdata) 1940 { } 1941 #endif /* CONFIG_SECURITY */ 1942 1943 #endif /* __KERNEL__ */ 1944 #endif /* _LINUX_FS_H */ 1945