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