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