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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#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>
Dipankar Sarmaab2af1f2005-09-09 13:04:13 -070012#include <linux/rcuref.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013
14/*
15 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
16 * the file limit at runtime and only root can increase the per-process
17 * nr_file rlimit, so it's safe to set up a ridiculously high absolute
18 * upper limit on files-per-process.
19 *
20 * Some programs (notably those using select()) may have to be
21 * recompiled to take full advantage of the new limits..
22 */
23
24/* Fixed constants first: */
25#undef NR_OPEN
26#define NR_OPEN (1024*1024) /* Absolute upper limit on fd num */
27#define INR_OPEN 1024 /* Initial setting for nfile rlimits */
28
29#define BLOCK_SIZE_BITS 10
30#define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
31
32/* And dynamically-tunable limits and defaults: */
33struct files_stat_struct {
34 int nr_files; /* read only */
35 int nr_free_files; /* read only */
36 int max_files; /* tunable */
37};
38extern struct files_stat_struct files_stat;
39
40struct inodes_stat_t {
41 int nr_inodes;
42 int nr_unused;
43 int dummy[5];
44};
45extern struct inodes_stat_t inodes_stat;
46
47extern int leases_enable, lease_break_time;
48
49#ifdef CONFIG_DNOTIFY
50extern int dir_notify_enable;
51#endif
52
53#define NR_FILE 8192 /* this can well be larger on a larger system */
54
55#define MAY_EXEC 1
56#define MAY_WRITE 2
57#define MAY_READ 4
58#define MAY_APPEND 8
59
60#define FMODE_READ 1
61#define FMODE_WRITE 2
62
63/* Internal kernel extensions */
64#define FMODE_LSEEK 4
65#define FMODE_PREAD 8
66#define FMODE_PWRITE FMODE_PREAD /* These go hand in hand */
67
68#define RW_MASK 1
69#define RWA_MASK 2
70#define READ 0
71#define WRITE 1
72#define READA 2 /* read-ahead - don't block if no resources */
Jan Karaa7662232005-09-06 15:19:10 -070073#define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */
Linus Torvalds1da177e2005-04-16 15:20:36 -070074#define SPECIAL 4 /* For non-blockdevice requests in request queue */
75#define READ_SYNC (READ | (1 << BIO_RW_SYNC))
76#define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC))
77#define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
78
79#define SEL_IN 1
80#define SEL_OUT 2
81#define SEL_EX 4
82
83/* public flags for file_system_type */
84#define FS_REQUIRES_DEV 1
85#define FS_BINARY_MOUNTDATA 2
86#define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
87#define FS_ODD_RENAME 32768 /* Temporary stuff; will go away as soon
88 * as nfs_rename() will be cleaned up
89 */
90/*
91 * These are the fs-independent mount-flags: up to 32 flags are supported
92 */
93#define MS_RDONLY 1 /* Mount read-only */
94#define MS_NOSUID 2 /* Ignore suid and sgid bits */
95#define MS_NODEV 4 /* Disallow access to device special files */
96#define MS_NOEXEC 8 /* Disallow program execution */
97#define MS_SYNCHRONOUS 16 /* Writes are synced at once */
98#define MS_REMOUNT 32 /* Alter flags of a mounted FS */
99#define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
100#define MS_DIRSYNC 128 /* Directory modifications are synchronous */
101#define MS_NOATIME 1024 /* Do not update access times. */
102#define MS_NODIRATIME 2048 /* Do not update directory access times */
103#define MS_BIND 4096
104#define MS_MOVE 8192
105#define MS_REC 16384
106#define MS_VERBOSE 32768
107#define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
108#define MS_ACTIVE (1<<30)
109#define MS_NOUSER (1<<31)
110
111/*
112 * Superblock flags that can be altered by MS_REMOUNT
113 */
114#define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_NOATIME|\
115 MS_NODIRATIME)
116
117/*
118 * Old magic mount flag and mask
119 */
120#define MS_MGC_VAL 0xC0ED0000
121#define MS_MGC_MSK 0xffff0000
122
123/* Inode flags - they have nothing to superblock flags now */
124
125#define S_SYNC 1 /* Writes are synced at once */
126#define S_NOATIME 2 /* Do not update access times */
127#define S_APPEND 4 /* Append-only file */
128#define S_IMMUTABLE 8 /* Immutable file */
129#define S_DEAD 16 /* removed, but still open directory */
130#define S_NOQUOTA 32 /* Inode is not counted to quota */
131#define S_DIRSYNC 64 /* Directory modifications are synchronous */
132#define S_NOCMTIME 128 /* Do not update file c/mtime */
133#define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
134#define S_PRIVATE 512 /* Inode is fs-internal */
135
136/*
137 * Note that nosuid etc flags are inode-specific: setting some file-system
138 * flags just means all the inodes inherit those flags by default. It might be
139 * possible to override it selectively if you really wanted to with some
140 * ioctl() that is not currently implemented.
141 *
142 * Exception: MS_RDONLY is always applied to the entire file system.
143 *
144 * Unfortunately, it is possible to change a filesystems flags with it mounted
145 * with files in use. This means that all of the inodes will not have their
146 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
147 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
148 */
149#define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
150
151#define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
152#define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
153 ((inode)->i_flags & S_SYNC))
154#define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
155 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
156#define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
157
158#define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
159#define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
160#define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
161#define IS_NOATIME(inode) (__IS_FLG(inode, MS_NOATIME) || ((inode)->i_flags & S_NOATIME))
162#define IS_NODIRATIME(inode) __IS_FLG(inode, MS_NODIRATIME)
163#define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
164
165#define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
166#define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
167#define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
168#define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
169
170/* the read-only stuff doesn't really belong here, but any other place is
171 probably as bad and I don't want to create yet another include file. */
172
173#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
174#define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
175#define BLKRRPART _IO(0x12,95) /* re-read partition table */
176#define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
177#define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
178#define BLKRASET _IO(0x12,98) /* set read ahead for block device */
179#define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
180#define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
181#define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
182#define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
183#define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
184#define BLKSSZGET _IO(0x12,104)/* get block device sector size */
185#if 0
186#define BLKPG _IO(0x12,105)/* See blkpg.h */
187
188/* Some people are morons. Do not use sizeof! */
189
190#define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
191#define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
192/* This was here just to show that the number is taken -
193 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
194#endif
195/* A jump here: 108-111 have been used for various private purposes. */
196#define BLKBSZGET _IOR(0x12,112,size_t)
197#define BLKBSZSET _IOW(0x12,113,size_t)
198#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
199
200#define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
201#define FIBMAP _IO(0x00,1) /* bmap access */
202#define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
203
204#ifdef __KERNEL__
205
206#include <linux/linkage.h>
207#include <linux/wait.h>
208#include <linux/types.h>
209#include <linux/kdev_t.h>
210#include <linux/dcache.h>
211#include <linux/stat.h>
212#include <linux/cache.h>
213#include <linux/kobject.h>
214#include <linux/list.h>
215#include <linux/radix-tree.h>
216#include <linux/prio_tree.h>
217#include <linux/init.h>
Jens Axboe22e2c502005-06-27 10:55:12 +0200218#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219
220#include <asm/atomic.h>
221#include <asm/semaphore.h>
222#include <asm/byteorder.h>
223
224struct iovec;
225struct nameidata;
Christoph Hellwig92198f72005-06-23 22:00:59 -0700226struct kiocb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227struct pipe_inode_info;
228struct poll_table_struct;
229struct kstatfs;
230struct vm_area_struct;
231struct vfsmount;
232
233/* Used to be a macro which just called the function, now just a function */
234extern void update_atime (struct inode *);
235
236extern void __init inode_init(unsigned long);
237extern void __init inode_init_early(void);
238extern void __init mnt_init(unsigned long);
239extern void __init files_init(unsigned long);
240
241struct buffer_head;
242typedef int (get_block_t)(struct inode *inode, sector_t iblock,
243 struct buffer_head *bh_result, int create);
244typedef int (get_blocks_t)(struct inode *inode, sector_t iblock,
245 unsigned long max_blocks,
246 struct buffer_head *bh_result, int create);
Christoph Hellwig92198f72005-06-23 22:00:59 -0700247typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 ssize_t bytes, void *private);
249
250/*
251 * Attribute flags. These should be or-ed together to figure out what
252 * has been changed!
253 */
254#define ATTR_MODE 1
255#define ATTR_UID 2
256#define ATTR_GID 4
257#define ATTR_SIZE 8
258#define ATTR_ATIME 16
259#define ATTR_MTIME 32
260#define ATTR_CTIME 64
261#define ATTR_ATIME_SET 128
262#define ATTR_MTIME_SET 256
263#define ATTR_FORCE 512 /* Not a change, but a change it */
264#define ATTR_ATTR_FLAG 1024
265#define ATTR_KILL_SUID 2048
266#define ATTR_KILL_SGID 4096
267
268/*
269 * This is the Inode Attributes structure, used for notify_change(). It
270 * uses the above definitions as flags, to know which values have changed.
271 * Also, in this manner, a Filesystem can look at only the values it cares
272 * about. Basically, these are the attributes that the VFS layer can
273 * request to change from the FS layer.
274 *
275 * Derek Atkins <warlord@MIT.EDU> 94-10-20
276 */
277struct iattr {
278 unsigned int ia_valid;
279 umode_t ia_mode;
280 uid_t ia_uid;
281 gid_t ia_gid;
282 loff_t ia_size;
283 struct timespec ia_atime;
284 struct timespec ia_mtime;
285 struct timespec ia_ctime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286};
287
288/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 * Includes for diskquotas.
290 */
291#include <linux/quota.h>
292
293/*
294 * oh the beauties of C type declarations.
295 */
296struct page;
297struct address_space;
298struct writeback_control;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
300struct address_space_operations {
301 int (*writepage)(struct page *page, struct writeback_control *wbc);
302 int (*readpage)(struct file *, struct page *);
303 int (*sync_page)(struct page *);
304
305 /* Write back some dirty pages from this mapping. */
306 int (*writepages)(struct address_space *, struct writeback_control *);
307
308 /* Set a page dirty */
309 int (*set_page_dirty)(struct page *page);
310
311 int (*readpages)(struct file *filp, struct address_space *mapping,
312 struct list_head *pages, unsigned nr_pages);
313
314 /*
315 * ext3 requires that a successful prepare_write() call be followed
316 * by a commit_write() call - they must be balanced
317 */
318 int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
319 int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
320 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
321 sector_t (*bmap)(struct address_space *, sector_t);
322 int (*invalidatepage) (struct page *, unsigned long);
Al Viro27496a82005-10-21 03:20:48 -0400323 int (*releasepage) (struct page *, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
325 loff_t offset, unsigned long nr_segs);
Carsten Otteceffc072005-06-23 22:05:25 -0700326 struct page* (*get_xip_page)(struct address_space *, sector_t,
327 int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328};
329
330struct backing_dev_info;
331struct address_space {
332 struct inode *host; /* owner: inode, block_device */
333 struct radix_tree_root page_tree; /* radix tree of all pages */
334 rwlock_t tree_lock; /* and rwlock protecting it */
335 unsigned int i_mmap_writable;/* count VM_SHARED mappings */
336 struct prio_tree_root i_mmap; /* tree of private and shared mappings */
337 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
338 spinlock_t i_mmap_lock; /* protect tree, count, list */
339 unsigned int truncate_count; /* Cover race condition with truncate */
340 unsigned long nrpages; /* number of total pages */
341 pgoff_t writeback_index;/* writeback starts here */
342 struct address_space_operations *a_ops; /* methods */
343 unsigned long flags; /* error bits/gfp mask */
344 struct backing_dev_info *backing_dev_info; /* device readahead, etc */
345 spinlock_t private_lock; /* for use by the address_space */
346 struct list_head private_list; /* ditto */
347 struct address_space *assoc_mapping; /* ditto */
348} __attribute__((aligned(sizeof(long))));
349 /*
350 * On most architectures that alignment is already the case; but
351 * must be enforced here for CRIS, to let the least signficant bit
352 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
353 */
354
355struct block_device {
356 dev_t bd_dev; /* not a kdev_t - it's a search key */
357 struct inode * bd_inode; /* will die */
358 int bd_openers;
359 struct semaphore bd_sem; /* open/close mutex */
360 struct semaphore bd_mount_sem; /* mount mutex */
361 struct list_head bd_inodes;
362 void * bd_holder;
363 int bd_holders;
364 struct block_device * bd_contains;
365 unsigned bd_block_size;
366 struct hd_struct * bd_part;
367 /* number of times partitions within this device have been opened. */
368 unsigned bd_part_count;
369 int bd_invalidated;
370 struct gendisk * bd_disk;
371 struct list_head bd_list;
372 struct backing_dev_info *bd_inode_backing_dev_info;
373 /*
374 * Private data. You must have bd_claim'ed the block_device
375 * to use this. NOTE: bd_claim allows an owner to claim
376 * the same device multiple times, the owner must take special
377 * care to not mess up bd_private for that case.
378 */
379 unsigned long bd_private;
380};
381
382/*
383 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
384 * radix trees
385 */
386#define PAGECACHE_TAG_DIRTY 0
387#define PAGECACHE_TAG_WRITEBACK 1
388
389int mapping_tagged(struct address_space *mapping, int tag);
390
391/*
392 * Might pages of this file be mapped into userspace?
393 */
394static inline int mapping_mapped(struct address_space *mapping)
395{
396 return !prio_tree_empty(&mapping->i_mmap) ||
397 !list_empty(&mapping->i_mmap_nonlinear);
398}
399
400/*
401 * Might pages of this file have been modified in userspace?
402 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
403 * marks vma as VM_SHARED if it is shared, and the file was opened for
404 * writing i.e. vma may be mprotected writable even if now readonly.
405 */
406static inline int mapping_writably_mapped(struct address_space *mapping)
407{
408 return mapping->i_mmap_writable != 0;
409}
410
411/*
412 * Use sequence counter to get consistent i_size on 32-bit processors.
413 */
414#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
415#include <linux/seqlock.h>
416#define __NEED_I_SIZE_ORDERED
417#define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
418#else
419#define i_size_ordered_init(inode) do { } while (0)
420#endif
421
422struct inode {
423 struct hlist_node i_hash;
424 struct list_head i_list;
425 struct list_head i_sb_list;
426 struct list_head i_dentry;
427 unsigned long i_ino;
428 atomic_t i_count;
429 umode_t i_mode;
430 unsigned int i_nlink;
431 uid_t i_uid;
432 gid_t i_gid;
433 dev_t i_rdev;
434 loff_t i_size;
435 struct timespec i_atime;
436 struct timespec i_mtime;
437 struct timespec i_ctime;
438 unsigned int i_blkbits;
439 unsigned long i_blksize;
440 unsigned long i_version;
441 unsigned long i_blocks;
442 unsigned short i_bytes;
443 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
444 struct semaphore i_sem;
445 struct rw_semaphore i_alloc_sem;
446 struct inode_operations *i_op;
447 struct file_operations *i_fop; /* former ->i_op->default_file_ops */
448 struct super_block *i_sb;
449 struct file_lock *i_flock;
450 struct address_space *i_mapping;
451 struct address_space i_data;
452#ifdef CONFIG_QUOTA
453 struct dquot *i_dquot[MAXQUOTAS];
454#endif
455 /* These three should probably be a union */
456 struct list_head i_devices;
457 struct pipe_inode_info *i_pipe;
458 struct block_device *i_bdev;
459 struct cdev *i_cdev;
460 int i_cindex;
461
462 __u32 i_generation;
463
464#ifdef CONFIG_DNOTIFY
465 unsigned long i_dnotify_mask; /* Directory notify events */
466 struct dnotify_struct *i_dnotify; /* for directory notifications */
467#endif
468
Robert Love0eeca282005-07-12 17:06:03 -0400469#ifdef CONFIG_INOTIFY
470 struct list_head inotify_watches; /* watches on this inode */
471 struct semaphore inotify_sem; /* protects the watches list */
472#endif
473
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 unsigned long i_state;
475 unsigned long dirtied_when; /* jiffies of first dirtying */
476
477 unsigned int i_flags;
478
479 atomic_t i_writecount;
480 void *i_security;
481 union {
482 void *generic_ip;
483 } u;
484#ifdef __NEED_I_SIZE_ORDERED
485 seqcount_t i_size_seqcount;
486#endif
487};
488
489/*
490 * NOTE: in a 32bit arch with a preemptable kernel and
491 * an UP compile the i_size_read/write must be atomic
492 * with respect to the local cpu (unlike with preempt disabled),
493 * but they don't need to be atomic with respect to other cpus like in
494 * true SMP (so they need either to either locally disable irq around
495 * the read or for example on x86 they can be still implemented as a
496 * cmpxchg8b without the need of the lock prefix). For SMP compiles
497 * and 64bit archs it makes no difference if preempt is enabled or not.
498 */
499static inline loff_t i_size_read(struct inode *inode)
500{
501#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
502 loff_t i_size;
503 unsigned int seq;
504
505 do {
506 seq = read_seqcount_begin(&inode->i_size_seqcount);
507 i_size = inode->i_size;
508 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
509 return i_size;
510#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
511 loff_t i_size;
512
513 preempt_disable();
514 i_size = inode->i_size;
515 preempt_enable();
516 return i_size;
517#else
518 return inode->i_size;
519#endif
520}
521
522
523static inline void i_size_write(struct inode *inode, loff_t i_size)
524{
525#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
526 write_seqcount_begin(&inode->i_size_seqcount);
527 inode->i_size = i_size;
528 write_seqcount_end(&inode->i_size_seqcount);
529#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
530 preempt_disable();
531 inode->i_size = i_size;
532 preempt_enable();
533#else
534 inode->i_size = i_size;
535#endif
536}
537
538static inline unsigned iminor(struct inode *inode)
539{
540 return MINOR(inode->i_rdev);
541}
542
543static inline unsigned imajor(struct inode *inode)
544{
545 return MAJOR(inode->i_rdev);
546}
547
548extern struct block_device *I_BDEV(struct inode *inode);
549
550struct fown_struct {
551 rwlock_t lock; /* protects pid, uid, euid fields */
552 int pid; /* pid or -pgrp where SIGIO should be sent */
553 uid_t uid, euid; /* uid/euid of process setting the owner */
554 void *security;
555 int signum; /* posix.1b rt signal to be delivered on IO */
556};
557
558/*
559 * Track a single file's readahead state
560 */
561struct file_ra_state {
562 unsigned long start; /* Current window */
563 unsigned long size;
564 unsigned long flags; /* ra flags RA_FLAG_xxx*/
565 unsigned long cache_hit; /* cache hit count*/
566 unsigned long prev_page; /* Cache last read() position */
567 unsigned long ahead_start; /* Ahead window */
568 unsigned long ahead_size;
569 unsigned long ra_pages; /* Maximum readahead window */
570 unsigned long mmap_hit; /* Cache hit stat for mmap accesses */
571 unsigned long mmap_miss; /* Cache miss stat for mmap accesses */
572};
573#define RA_FLAG_MISS 0x01 /* a cache miss occured against this file */
574#define RA_FLAG_INCACHE 0x02 /* file is already in cache */
575
576struct file {
Eric Dumazet2f512012005-10-30 15:02:16 -0800577 /*
578 * fu_list becomes invalid after file_free is called and queued via
579 * fu_rcuhead for RCU freeing
580 */
581 union {
582 struct list_head fu_list;
583 struct rcu_head fu_rcuhead;
584 } f_u;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 struct dentry *f_dentry;
586 struct vfsmount *f_vfsmnt;
587 struct file_operations *f_op;
588 atomic_t f_count;
589 unsigned int f_flags;
590 mode_t f_mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 loff_t f_pos;
592 struct fown_struct f_owner;
593 unsigned int f_uid, f_gid;
594 struct file_ra_state f_ra;
595
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 unsigned long f_version;
597 void *f_security;
598
599 /* needed for tty driver, and maybe others */
600 void *private_data;
601
602#ifdef CONFIG_EPOLL
603 /* Used by fs/eventpoll.c to link all the hooks to this file */
604 struct list_head f_ep_links;
605 spinlock_t f_ep_lock;
606#endif /* #ifdef CONFIG_EPOLL */
607 struct address_space *f_mapping;
608};
609extern spinlock_t files_lock;
610#define file_list_lock() spin_lock(&files_lock);
611#define file_list_unlock() spin_unlock(&files_lock);
612
Dipankar Sarmaab2af1f2005-09-09 13:04:13 -0700613#define get_file(x) rcuref_inc(&(x)->f_count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614#define file_count(x) atomic_read(&(x)->f_count)
615
616#define MAX_NON_LFS ((1UL<<31) - 1)
617
618/* Page cache limit. The filesystems should put that into their s_maxbytes
619 limits, otherwise bad things can happen in VM. */
620#if BITS_PER_LONG==32
621#define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
622#elif BITS_PER_LONG==64
623#define MAX_LFS_FILESIZE 0x7fffffffffffffffUL
624#endif
625
626#define FL_POSIX 1
627#define FL_FLOCK 2
628#define FL_ACCESS 8 /* not trying to lock, just looking */
629#define FL_LOCKD 16 /* lock held by rpc.lockd */
630#define FL_LEASE 32 /* lease held on this file */
631#define FL_SLEEP 128 /* A blocking lock */
632
633/*
634 * The POSIX file lock owner is determined by
635 * the "struct files_struct" in the thread group
636 * (or NULL for no owner - BSD locks).
637 *
638 * Lockd stuffs a "host" pointer into this.
639 */
640typedef struct files_struct *fl_owner_t;
641
642struct file_lock_operations {
643 void (*fl_insert)(struct file_lock *); /* lock insertion callback */
644 void (*fl_remove)(struct file_lock *); /* lock removal callback */
645 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
646 void (*fl_release_private)(struct file_lock *);
647};
648
649struct lock_manager_operations {
650 int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
651 void (*fl_notify)(struct file_lock *); /* unblock callback */
652 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
653 void (*fl_release_private)(struct file_lock *);
654 void (*fl_break)(struct file_lock *);
655 int (*fl_mylease)(struct file_lock *, struct file_lock *);
656 int (*fl_change)(struct file_lock **, int);
657};
658
659/* that will die - we need it for nfs_lock_info */
660#include <linux/nfs_fs_i.h>
661
662struct file_lock {
663 struct file_lock *fl_next; /* singly linked list for this inode */
664 struct list_head fl_link; /* doubly linked list of all locks */
665 struct list_head fl_block; /* circular list of blocked processes */
666 fl_owner_t fl_owner;
667 unsigned int fl_pid;
668 wait_queue_head_t fl_wait;
669 struct file *fl_file;
670 unsigned char fl_flags;
671 unsigned char fl_type;
672 loff_t fl_start;
673 loff_t fl_end;
674
675 struct fasync_struct * fl_fasync; /* for lease break notifications */
676 unsigned long fl_break_time; /* for nonblocking lease breaks */
677
678 struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
679 struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
680 union {
681 struct nfs_lock_info nfs_fl;
Trond Myklebust8d0a8a92005-06-22 17:16:32 +0000682 struct nfs4_lock_info nfs4_fl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683 } fl_u;
684};
685
686/* The following constant reflects the upper bound of the file/locking space */
687#ifndef OFFSET_MAX
688#define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
689#define OFFSET_MAX INT_LIMIT(loff_t)
690#define OFFT_OFFSET_MAX INT_LIMIT(off_t)
691#endif
692
693extern struct list_head file_lock_list;
694
695#include <linux/fcntl.h>
696
697extern int fcntl_getlk(struct file *, struct flock __user *);
Peter Staubachc2936212005-07-27 11:45:09 -0700698extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
699 struct flock __user *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700
701#if BITS_PER_LONG == 32
702extern int fcntl_getlk64(struct file *, struct flock64 __user *);
Peter Staubachc2936212005-07-27 11:45:09 -0700703extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
704 struct flock64 __user *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705#endif
706
707extern void send_sigio(struct fown_struct *fown, int fd, int band);
708extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
709extern int fcntl_getlease(struct file *filp);
710
711/* fs/locks.c */
712extern void locks_init_lock(struct file_lock *);
713extern void locks_copy_lock(struct file_lock *, struct file_lock *);
714extern void locks_remove_posix(struct file *, fl_owner_t);
715extern void locks_remove_flock(struct file *);
716extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
717extern int posix_lock_file(struct file *, struct file_lock *);
718extern int posix_lock_file_wait(struct file *, struct file_lock *);
719extern void posix_block_lock(struct file_lock *, struct file_lock *);
720extern void posix_unblock_lock(struct file *, struct file_lock *);
721extern int posix_locks_deadlock(struct file_lock *, struct file_lock *);
722extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
723extern int __break_lease(struct inode *inode, unsigned int flags);
724extern void lease_get_mtime(struct inode *, struct timespec *time);
725extern int setlease(struct file *, long, struct file_lock **);
726extern int lease_modify(struct file_lock **, int);
727extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
728extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
729extern void steal_locks(fl_owner_t from);
730
731struct fasync_struct {
732 int magic;
733 int fa_fd;
734 struct fasync_struct *fa_next; /* singly linked list */
735 struct file *fa_file;
736};
737
738#define FASYNC_MAGIC 0x4601
739
740/* SMP safe fasync helpers: */
741extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
742/* can be called from interrupts */
743extern void kill_fasync(struct fasync_struct **, int, int);
744/* only for net: no internal synchronization */
745extern void __kill_fasync(struct fasync_struct *, int, int);
746
747extern int f_setown(struct file *filp, unsigned long arg, int force);
748extern void f_delown(struct file *filp);
749extern int send_sigurg(struct fown_struct *fown);
750
751/*
752 * Umount options
753 */
754
755#define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
756#define MNT_DETACH 0x00000002 /* Just detach from the tree */
757#define MNT_EXPIRE 0x00000004 /* Mark for expiry */
758
759extern struct list_head super_blocks;
760extern spinlock_t sb_lock;
761
762#define sb_entry(list) list_entry((list), struct super_block, s_list)
763#define S_BIAS (1<<30)
764struct super_block {
765 struct list_head s_list; /* Keep this first */
766 dev_t s_dev; /* search index; _not_ kdev_t */
767 unsigned long s_blocksize;
768 unsigned long s_old_blocksize;
769 unsigned char s_blocksize_bits;
770 unsigned char s_dirt;
771 unsigned long long s_maxbytes; /* Max file size */
772 struct file_system_type *s_type;
773 struct super_operations *s_op;
774 struct dquot_operations *dq_op;
775 struct quotactl_ops *s_qcop;
776 struct export_operations *s_export_op;
777 unsigned long s_flags;
778 unsigned long s_magic;
779 struct dentry *s_root;
780 struct rw_semaphore s_umount;
781 struct semaphore s_lock;
782 int s_count;
783 int s_syncing;
784 int s_need_sync_fs;
785 atomic_t s_active;
786 void *s_security;
787 struct xattr_handler **s_xattr;
788
789 struct list_head s_inodes; /* all inodes */
790 struct list_head s_dirty; /* dirty inodes */
791 struct list_head s_io; /* parked for writeback */
792 struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */
793 struct list_head s_files;
794
795 struct block_device *s_bdev;
796 struct list_head s_instances;
797 struct quota_info s_dquot; /* Diskquota specific options */
798
799 int s_frozen;
800 wait_queue_head_t s_wait_unfrozen;
801
802 char s_id[32]; /* Informational name */
803
804 void *s_fs_info; /* Filesystem private info */
805
806 /*
807 * The next field is for VFS *only*. No filesystems have any business
808 * even looking at it. You had been warned.
809 */
810 struct semaphore s_vfs_rename_sem; /* Kludge */
811
812 /* Granuality of c/m/atime in ns.
813 Cannot be worse than a second */
814 u32 s_time_gran;
815};
816
817extern struct timespec current_fs_time(struct super_block *sb);
818
819/*
820 * Snapshotting support.
821 */
822enum {
823 SB_UNFROZEN = 0,
824 SB_FREEZE_WRITE = 1,
825 SB_FREEZE_TRANS = 2,
826};
827
828#define vfs_check_frozen(sb, level) \
829 wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level)))
830
Jens Axboe22e2c502005-06-27 10:55:12 +0200831static inline void get_fs_excl(void)
832{
833 atomic_inc(&current->fs_excl);
834}
835
836static inline void put_fs_excl(void)
837{
838 atomic_dec(&current->fs_excl);
839}
840
841static inline int has_fs_excl(void)
842{
843 return atomic_read(&current->fs_excl);
844}
845
846
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847/*
848 * Superblock locking.
849 */
850static inline void lock_super(struct super_block * sb)
851{
Jens Axboe22e2c502005-06-27 10:55:12 +0200852 get_fs_excl();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853 down(&sb->s_lock);
854}
855
856static inline void unlock_super(struct super_block * sb)
857{
Jens Axboe22e2c502005-06-27 10:55:12 +0200858 put_fs_excl();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 up(&sb->s_lock);
860}
861
862/*
863 * VFS helper functions..
864 */
865extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
866extern int vfs_mkdir(struct inode *, struct dentry *, int);
867extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
868extern int vfs_symlink(struct inode *, struct dentry *, const char *, int);
869extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
870extern int vfs_rmdir(struct inode *, struct dentry *);
871extern int vfs_unlink(struct inode *, struct dentry *);
872extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
873
874/*
875 * VFS dentry helper functions.
876 */
877extern void dentry_unhash(struct dentry *dentry);
878
879/*
880 * File types
881 *
882 * NOTE! These match bits 12..15 of stat.st_mode
883 * (ie "(i_mode >> 12) & 15").
884 */
885#define DT_UNKNOWN 0
886#define DT_FIFO 1
887#define DT_CHR 2
888#define DT_DIR 4
889#define DT_BLK 6
890#define DT_REG 8
891#define DT_LNK 10
892#define DT_SOCK 12
893#define DT_WHT 14
894
895#define OSYNC_METADATA (1<<0)
896#define OSYNC_DATA (1<<1)
897#define OSYNC_INODE (1<<2)
898int generic_osync_inode(struct inode *, struct address_space *, int);
899
900/*
901 * This is the "filldir" function type, used by readdir() to let
902 * the kernel specify what kind of dirent layout it wants to have.
903 * This allows the kernel to read directories into kernel space or
904 * to have different dirent layouts depending on the binary type.
905 */
906typedef int (*filldir_t)(void *, const char *, int, loff_t, ino_t, unsigned);
907
908struct block_device_operations {
909 int (*open) (struct inode *, struct file *);
910 int (*release) (struct inode *, struct file *);
911 int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
Arnd Bergmannbb93e3a2005-06-23 00:10:15 -0700912 long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913 long (*compat_ioctl) (struct file *, unsigned, unsigned long);
Carsten Otte420edbc2005-06-23 22:05:23 -0700914 int (*direct_access) (struct block_device *, sector_t, unsigned long *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 int (*media_changed) (struct gendisk *);
916 int (*revalidate_disk) (struct gendisk *);
917 struct module *owner;
918};
919
920/*
921 * "descriptor" for what we're up to with a read for sendfile().
922 * This allows us to use the same read code yet
923 * have multiple different users of the data that
924 * we read from a file.
925 *
926 * The simplest case just copies the data to user
927 * mode.
928 */
929typedef struct {
930 size_t written;
931 size_t count;
932 union {
933 char __user * buf;
934 void *data;
935 } arg;
936 int error;
937} read_descriptor_t;
938
939typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long);
940
941/* These macros are for out of kernel modules to test that
942 * the kernel supports the unlocked_ioctl and compat_ioctl
943 * fields in struct file_operations. */
944#define HAVE_COMPAT_IOCTL 1
945#define HAVE_UNLOCKED_IOCTL 1
946
947/*
948 * NOTE:
949 * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl
950 * can be called without the big kernel lock held in all filesystems.
951 */
952struct file_operations {
953 struct module *owner;
954 loff_t (*llseek) (struct file *, loff_t, int);
955 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
956 ssize_t (*aio_read) (struct kiocb *, char __user *, size_t, loff_t);
957 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
958 ssize_t (*aio_write) (struct kiocb *, const char __user *, size_t, loff_t);
959 int (*readdir) (struct file *, void *, filldir_t);
960 unsigned int (*poll) (struct file *, struct poll_table_struct *);
961 int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
962 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
963 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
964 int (*mmap) (struct file *, struct vm_area_struct *);
965 int (*open) (struct inode *, struct file *);
966 int (*flush) (struct file *);
967 int (*release) (struct inode *, struct file *);
968 int (*fsync) (struct file *, struct dentry *, int datasync);
969 int (*aio_fsync) (struct kiocb *, int datasync);
970 int (*fasync) (int, struct file *, int);
971 int (*lock) (struct file *, int, struct file_lock *);
972 ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *);
973 ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *);
974 ssize_t (*sendfile) (struct file *, loff_t *, size_t, read_actor_t, void *);
975 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
976 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
977 int (*check_flags)(int);
978 int (*dir_notify)(struct file *filp, unsigned long arg);
979 int (*flock) (struct file *, int, struct file_lock *);
980};
981
982struct inode_operations {
983 int (*create) (struct inode *,struct dentry *,int, struct nameidata *);
984 struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
985 int (*link) (struct dentry *,struct inode *,struct dentry *);
986 int (*unlink) (struct inode *,struct dentry *);
987 int (*symlink) (struct inode *,struct dentry *,const char *);
988 int (*mkdir) (struct inode *,struct dentry *,int);
989 int (*rmdir) (struct inode *,struct dentry *);
990 int (*mknod) (struct inode *,struct dentry *,int,dev_t);
991 int (*rename) (struct inode *, struct dentry *,
992 struct inode *, struct dentry *);
993 int (*readlink) (struct dentry *, char __user *,int);
Linus Torvaldscc314ee2005-08-19 18:02:56 -0700994 void * (*follow_link) (struct dentry *, struct nameidata *);
995 void (*put_link) (struct dentry *, struct nameidata *, void *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 void (*truncate) (struct inode *);
997 int (*permission) (struct inode *, int, struct nameidata *);
998 int (*setattr) (struct dentry *, struct iattr *);
999 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
1000 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
1001 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
1002 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1003 int (*removexattr) (struct dentry *, const char *);
1004};
1005
1006struct seq_file;
1007
1008extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1009extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1010extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1011 unsigned long, loff_t *);
1012extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
1013 unsigned long, loff_t *);
1014
1015/*
1016 * NOTE: write_inode, delete_inode, clear_inode, put_inode can be called
1017 * without the big kernel lock held in all filesystems.
1018 */
1019struct super_operations {
1020 struct inode *(*alloc_inode)(struct super_block *sb);
1021 void (*destroy_inode)(struct inode *);
1022
1023 void (*read_inode) (struct inode *);
1024
1025 void (*dirty_inode) (struct inode *);
1026 int (*write_inode) (struct inode *, int);
1027 void (*put_inode) (struct inode *);
1028 void (*drop_inode) (struct inode *);
1029 void (*delete_inode) (struct inode *);
1030 void (*put_super) (struct super_block *);
1031 void (*write_super) (struct super_block *);
1032 int (*sync_fs)(struct super_block *sb, int wait);
1033 void (*write_super_lockfs) (struct super_block *);
1034 void (*unlockfs) (struct super_block *);
1035 int (*statfs) (struct super_block *, struct kstatfs *);
1036 int (*remount_fs) (struct super_block *, int *, char *);
1037 void (*clear_inode) (struct inode *);
1038 void (*umount_begin) (struct super_block *);
1039
1040 int (*show_options)(struct seq_file *, struct vfsmount *);
1041
1042 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1043 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1044};
1045
1046/* Inode state bits. Protected by inode_lock. */
1047#define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */
1048#define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */
1049#define I_DIRTY_PAGES 4 /* Data-related inode changes pending */
1050#define __I_LOCK 3
1051#define I_LOCK (1 << __I_LOCK)
1052#define I_FREEING 16
1053#define I_CLEAR 32
1054#define I_NEW 64
Alexander Viro991114c2005-06-23 00:09:01 -07001055#define I_WILL_FREE 128
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056
1057#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1058
1059extern void __mark_inode_dirty(struct inode *, int);
1060static inline void mark_inode_dirty(struct inode *inode)
1061{
1062 __mark_inode_dirty(inode, I_DIRTY);
1063}
1064
1065static inline void mark_inode_dirty_sync(struct inode *inode)
1066{
1067 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1068}
1069
1070static inline void touch_atime(struct vfsmount *mnt, struct dentry *dentry)
1071{
1072 /* per-mountpoint checks will go here */
1073 update_atime(dentry->d_inode);
1074}
1075
1076static inline void file_accessed(struct file *file)
1077{
1078 if (!(file->f_flags & O_NOATIME))
1079 touch_atime(file->f_vfsmnt, file->f_dentry);
1080}
1081
1082int sync_inode(struct inode *inode, struct writeback_control *wbc);
1083
1084/**
Pavel Pisa4dc3b162005-05-01 08:59:25 -07001085 * struct export_operations - for nfsd to communicate with file systems
1086 * @decode_fh: decode a file handle fragment and return a &struct dentry
1087 * @encode_fh: encode a file handle fragment from a dentry
1088 * @get_name: find the name for a given inode in a given directory
1089 * @get_parent: find the parent of a given directory
1090 * @get_dentry: find a dentry for the inode given a file handle sub-fragment
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091 *
1092 * Description:
1093 * The export_operations structure provides a means for nfsd to communicate
1094 * with a particular exported file system - particularly enabling nfsd and
1095 * the filesystem to co-operate when dealing with file handles.
1096 *
Martin Waitz67be2dd2005-05-01 08:59:26 -07001097 * export_operations contains two basic operation for dealing with file
1098 * handles, decode_fh() and encode_fh(), and allows for some other
1099 * operations to be defined which standard helper routines use to get
1100 * specific information from the filesystem.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101 *
1102 * nfsd encodes information use to determine which filesystem a filehandle
Martin Waitz67be2dd2005-05-01 08:59:26 -07001103 * applies to in the initial part of the file handle. The remainder, termed
1104 * a file handle fragment, is controlled completely by the filesystem. The
1105 * standard helper routines assume that this fragment will contain one or
1106 * two sub-fragments, one which identifies the file, and one which may be
1107 * used to identify the (a) directory containing the file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001108 *
1109 * In some situations, nfsd needs to get a dentry which is connected into a
Martin Waitz67be2dd2005-05-01 08:59:26 -07001110 * specific part of the file tree. To allow for this, it passes the
1111 * function acceptable() together with a @context which can be used to see
1112 * if the dentry is acceptable. As there can be multiple dentrys for a
1113 * given file, the filesystem should check each one for acceptability before
1114 * looking for the next. As soon as an acceptable one is found, it should
1115 * be returned.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 *
1117 * decode_fh:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001118 * @decode_fh is given a &struct super_block (@sb), a file handle fragment
1119 * (@fh, @fh_len) and an acceptability testing function (@acceptable,
1120 * @context). It should return a &struct dentry which refers to the same
1121 * file that the file handle fragment refers to, and which passes the
1122 * acceptability test. If it cannot, it should return a %NULL pointer if
1123 * the file was found but no acceptable &dentries were available, or a
1124 * %ERR_PTR error code indicating why it couldn't be found (e.g. %ENOENT or
1125 * %ENOMEM).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001126 *
1127 * encode_fh:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001128 * @encode_fh should store in the file handle fragment @fh (using at most
1129 * @max_len bytes) information that can be used by @decode_fh to recover the
1130 * file refered to by the &struct dentry @de. If the @connectable flag is
1131 * set, the encode_fh() should store sufficient information so that a good
1132 * attempt can be made to find not only the file but also it's place in the
1133 * filesystem. This typically means storing a reference to de->d_parent in
1134 * the filehandle fragment. encode_fh() should return the number of bytes
1135 * stored or a negative error code such as %-ENOSPC
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136 *
1137 * get_name:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001138 * @get_name should find a name for the given @child in the given @parent
1139 * directory. The name should be stored in the @name (with the
1140 * understanding that it is already pointing to a a %NAME_MAX+1 sized
1141 * buffer. get_name() should return %0 on success, a negative error code
1142 * or error. @get_name will be called without @parent->i_sem held.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143 *
1144 * get_parent:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001145 * @get_parent should find the parent directory for the given @child which
1146 * is also a directory. In the event that it cannot be found, or storage
1147 * space cannot be allocated, a %ERR_PTR should be returned.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148 *
1149 * get_dentry:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001150 * Given a &super_block (@sb) and a pointer to a file-system specific inode
1151 * identifier, possibly an inode number, (@inump) get_dentry() should find
1152 * the identified inode and return a dentry for that inode. Any suitable
1153 * dentry can be returned including, if necessary, a new dentry created with
1154 * d_alloc_root. The caller can then find any other extant dentrys by
1155 * following the d_alias links. If a new dentry was created using
1156 * d_alloc_root, DCACHE_NFSD_DISCONNECTED should be set, and the dentry
1157 * should be d_rehash()ed.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158 *
Martin Waitz67be2dd2005-05-01 08:59:26 -07001159 * If the inode cannot be found, either a %NULL pointer or an %ERR_PTR code
1160 * can be returned. The @inump will be whatever was passed to
1161 * nfsd_find_fh_dentry() in either the @obj or @parent parameters.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162 *
1163 * Locking rules:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001164 * get_parent is called with child->d_inode->i_sem down
1165 * get_name is not (which is possibly inconsistent)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166 */
1167
1168struct export_operations {
1169 struct dentry *(*decode_fh)(struct super_block *sb, __u32 *fh, int fh_len, int fh_type,
1170 int (*acceptable)(void *context, struct dentry *de),
1171 void *context);
1172 int (*encode_fh)(struct dentry *de, __u32 *fh, int *max_len,
1173 int connectable);
1174
1175 /* the following are only called from the filesystem itself */
1176 int (*get_name)(struct dentry *parent, char *name,
1177 struct dentry *child);
1178 struct dentry * (*get_parent)(struct dentry *child);
1179 struct dentry * (*get_dentry)(struct super_block *sb, void *inump);
1180
1181 /* This is set by the exporting module to a standard helper */
1182 struct dentry * (*find_exported_dentry)(
1183 struct super_block *sb, void *obj, void *parent,
1184 int (*acceptable)(void *context, struct dentry *de),
1185 void *context);
1186
1187
1188};
1189
1190extern struct dentry *
1191find_exported_dentry(struct super_block *sb, void *obj, void *parent,
1192 int (*acceptable)(void *context, struct dentry *de),
1193 void *context);
1194
1195struct file_system_type {
1196 const char *name;
1197 int fs_flags;
1198 struct super_block *(*get_sb) (struct file_system_type *, int,
1199 const char *, void *);
1200 void (*kill_sb) (struct super_block *);
1201 struct module *owner;
1202 struct file_system_type * next;
1203 struct list_head fs_supers;
1204};
1205
1206struct super_block *get_sb_bdev(struct file_system_type *fs_type,
1207 int flags, const char *dev_name, void *data,
1208 int (*fill_super)(struct super_block *, void *, int));
1209struct super_block *get_sb_single(struct file_system_type *fs_type,
1210 int flags, void *data,
1211 int (*fill_super)(struct super_block *, void *, int));
1212struct super_block *get_sb_nodev(struct file_system_type *fs_type,
1213 int flags, void *data,
1214 int (*fill_super)(struct super_block *, void *, int));
1215void generic_shutdown_super(struct super_block *sb);
1216void kill_block_super(struct super_block *sb);
1217void kill_anon_super(struct super_block *sb);
1218void kill_litter_super(struct super_block *sb);
1219void deactivate_super(struct super_block *sb);
1220int set_anon_super(struct super_block *s, void *data);
1221struct super_block *sget(struct file_system_type *type,
1222 int (*test)(struct super_block *,void *),
1223 int (*set)(struct super_block *,void *),
1224 void *data);
1225struct super_block *get_sb_pseudo(struct file_system_type *, char *,
1226 struct super_operations *ops, unsigned long);
1227int __put_super(struct super_block *sb);
1228int __put_super_and_need_restart(struct super_block *sb);
1229void unnamed_dev_init(void);
1230
1231/* Alas, no aliases. Too much hassle with bringing module.h everywhere */
1232#define fops_get(fops) \
1233 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
1234#define fops_put(fops) \
1235 do { if (fops) module_put((fops)->owner); } while(0)
1236
1237extern int register_filesystem(struct file_system_type *);
1238extern int unregister_filesystem(struct file_system_type *);
1239extern struct vfsmount *kern_mount(struct file_system_type *);
1240extern int may_umount_tree(struct vfsmount *);
1241extern int may_umount(struct vfsmount *);
1242extern long do_mount(char *, char *, char *, unsigned long, void *);
1243
1244extern int vfs_statfs(struct super_block *, struct kstatfs *);
1245
1246#define FLOCK_VERIFY_READ 1
1247#define FLOCK_VERIFY_WRITE 2
1248
1249extern int locks_mandatory_locked(struct inode *);
1250extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
1251
1252/*
1253 * Candidates for mandatory locking have the setgid bit set
1254 * but no group execute bit - an otherwise meaningless combination.
1255 */
1256#define MANDATORY_LOCK(inode) \
1257 (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
1258
1259static inline int locks_verify_locked(struct inode *inode)
1260{
1261 if (MANDATORY_LOCK(inode))
1262 return locks_mandatory_locked(inode);
1263 return 0;
1264}
1265
1266extern int rw_verify_area(int, struct file *, loff_t *, size_t);
1267
1268static inline int locks_verify_truncate(struct inode *inode,
1269 struct file *filp,
1270 loff_t size)
1271{
1272 if (inode->i_flock && MANDATORY_LOCK(inode))
1273 return locks_mandatory_area(
1274 FLOCK_VERIFY_WRITE, inode, filp,
1275 size < inode->i_size ? size : inode->i_size,
1276 (size < inode->i_size ? inode->i_size - size
1277 : size - inode->i_size)
1278 );
1279 return 0;
1280}
1281
1282static inline int break_lease(struct inode *inode, unsigned int mode)
1283{
1284 if (inode->i_flock)
1285 return __break_lease(inode, mode);
1286 return 0;
1287}
1288
1289/* fs/open.c */
1290
1291extern int do_truncate(struct dentry *, loff_t start);
Miklos Szeredie922efc2005-09-06 15:18:25 -07001292extern long do_sys_open(const char __user *filename, int flags, int mode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293extern struct file *filp_open(const char *, int, int);
1294extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
1295extern int filp_close(struct file *, fl_owner_t id);
1296extern char * getname(const char __user *);
1297
1298/* fs/dcache.c */
1299extern void __init vfs_caches_init_early(void);
1300extern void __init vfs_caches_init(unsigned long);
1301
1302#define __getname() kmem_cache_alloc(names_cachep, SLAB_KERNEL)
1303#define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
1304#ifndef CONFIG_AUDITSYSCALL
1305#define putname(name) __putname(name)
1306#else
1307extern void putname(const char *name);
1308#endif
1309
1310extern int register_blkdev(unsigned int, const char *);
1311extern int unregister_blkdev(unsigned int, const char *);
1312extern struct block_device *bdget(dev_t);
1313extern void bd_set_size(struct block_device *, loff_t size);
1314extern void bd_forget(struct inode *inode);
1315extern void bdput(struct block_device *);
1316extern struct block_device *open_by_devnum(dev_t, unsigned);
1317extern struct file_operations def_blk_fops;
1318extern struct address_space_operations def_blk_aops;
1319extern struct file_operations def_chr_fops;
1320extern struct file_operations bad_sock_fops;
1321extern struct file_operations def_fifo_fops;
1322extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
1323extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
1324extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
1325extern int blkdev_get(struct block_device *, mode_t, unsigned);
1326extern int blkdev_put(struct block_device *);
1327extern int bd_claim(struct block_device *, void *);
1328extern void bd_release(struct block_device *);
1329
1330/* fs/char_dev.c */
1331extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
1332extern int register_chrdev_region(dev_t, unsigned, const char *);
1333extern int register_chrdev(unsigned int, const char *,
1334 struct file_operations *);
1335extern int unregister_chrdev(unsigned int, const char *);
1336extern void unregister_chrdev_region(dev_t, unsigned);
1337extern int chrdev_open(struct inode *, struct file *);
1338
1339/* fs/block_dev.c */
1340#define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
1341extern const char *__bdevname(dev_t, char *buffer);
1342extern const char *bdevname(struct block_device *bdev, char *buffer);
1343extern struct block_device *lookup_bdev(const char *);
1344extern struct block_device *open_bdev_excl(const char *, int, void *);
1345extern void close_bdev_excl(struct block_device *);
1346
1347extern void init_special_inode(struct inode *, umode_t, dev_t);
1348
1349/* Invalid inode operations -- fs/bad_inode.c */
1350extern void make_bad_inode(struct inode *);
1351extern int is_bad_inode(struct inode *);
1352
1353extern struct file_operations read_fifo_fops;
1354extern struct file_operations write_fifo_fops;
1355extern struct file_operations rdwr_fifo_fops;
1356extern struct file_operations read_pipe_fops;
1357extern struct file_operations write_pipe_fops;
1358extern struct file_operations rdwr_pipe_fops;
1359
1360extern int fs_may_remount_ro(struct super_block *);
1361
1362/*
1363 * return READ, READA, or WRITE
1364 */
1365#define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
1366
1367/*
1368 * return data direction, READ or WRITE
1369 */
1370#define bio_data_dir(bio) ((bio)->bi_rw & 1)
1371
1372extern int check_disk_change(struct block_device *);
1373extern int invalidate_inodes(struct super_block *);
Christoph Hellwig2ef41632005-05-05 16:15:59 -07001374extern int __invalidate_device(struct block_device *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001375extern int invalidate_partition(struct gendisk *, int);
1376unsigned long invalidate_mapping_pages(struct address_space *mapping,
1377 pgoff_t start, pgoff_t end);
1378unsigned long invalidate_inode_pages(struct address_space *mapping);
1379static inline void invalidate_remote_inode(struct inode *inode)
1380{
1381 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1382 S_ISLNK(inode->i_mode))
1383 invalidate_inode_pages(inode->i_mapping);
1384}
1385extern int invalidate_inode_pages2(struct address_space *mapping);
1386extern int invalidate_inode_pages2_range(struct address_space *mapping,
1387 pgoff_t start, pgoff_t end);
1388extern int write_inode_now(struct inode *, int);
1389extern int filemap_fdatawrite(struct address_space *);
1390extern int filemap_flush(struct address_space *);
1391extern int filemap_fdatawait(struct address_space *);
1392extern int filemap_write_and_wait(struct address_space *mapping);
1393extern int filemap_write_and_wait_range(struct address_space *mapping,
1394 loff_t lstart, loff_t lend);
1395extern void sync_supers(void);
1396extern void sync_filesystems(int wait);
1397extern void emergency_sync(void);
1398extern void emergency_remount(void);
1399extern int do_remount_sb(struct super_block *sb, int flags,
1400 void *data, int force);
1401extern sector_t bmap(struct inode *, sector_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001402extern int notify_change(struct dentry *, struct iattr *);
1403extern int permission(struct inode *, int, struct nameidata *);
1404extern int generic_permission(struct inode *, int,
1405 int (*check_acl)(struct inode *, int));
1406
1407extern int get_write_access(struct inode *);
1408extern int deny_write_access(struct file *);
1409static inline void put_write_access(struct inode * inode)
1410{
1411 atomic_dec(&inode->i_writecount);
1412}
1413static inline void allow_write_access(struct file *file)
1414{
1415 if (file)
1416 atomic_inc(&file->f_dentry->d_inode->i_writecount);
1417}
1418extern int do_pipe(int *);
1419
1420extern int open_namei(const char *, int, int, struct nameidata *);
1421extern int may_open(struct nameidata *, int, int);
1422
1423extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
1424extern struct file * open_exec(const char *);
1425
1426/* fs/dcache.c -- generic fs support functions */
1427extern int is_subdir(struct dentry *, struct dentry *);
1428extern ino_t find_inode_number(struct dentry *, struct qstr *);
1429
1430#include <linux/err.h>
1431
1432/* needed for stackable file system support */
1433extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
1434
1435extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
1436
1437extern void inode_init_once(struct inode *);
1438extern void iput(struct inode *);
1439extern struct inode * igrab(struct inode *);
1440extern ino_t iunique(struct super_block *, ino_t);
1441extern int inode_needs_sync(struct inode *inode);
1442extern void generic_delete_inode(struct inode *inode);
Mark Fashehcb2c0232005-07-07 17:56:03 -07001443extern void generic_drop_inode(struct inode *inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001444
Anton Altaparmakov88bd5122005-07-13 01:10:44 -07001445extern struct inode *ilookup5_nowait(struct super_block *sb,
1446 unsigned long hashval, int (*test)(struct inode *, void *),
1447 void *data);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001448extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
1449 int (*test)(struct inode *, void *), void *data);
1450extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
1451
1452extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
1453extern struct inode * iget_locked(struct super_block *, unsigned long);
1454extern void unlock_new_inode(struct inode *);
1455
1456static inline struct inode *iget(struct super_block *sb, unsigned long ino)
1457{
1458 struct inode *inode = iget_locked(sb, ino);
1459
1460 if (inode && (inode->i_state & I_NEW)) {
1461 sb->s_op->read_inode(inode);
1462 unlock_new_inode(inode);
1463 }
1464
1465 return inode;
1466}
1467
1468extern void __iget(struct inode * inode);
1469extern void clear_inode(struct inode *);
1470extern void destroy_inode(struct inode *);
1471extern struct inode *new_inode(struct super_block *);
1472extern int remove_suid(struct dentry *);
1473extern void remove_dquot_ref(struct super_block *, int, struct list_head *);
1474extern struct semaphore iprune_sem;
1475
1476extern void __insert_inode_hash(struct inode *, unsigned long hashval);
1477extern void remove_inode_hash(struct inode *);
1478static inline void insert_inode_hash(struct inode *inode) {
1479 __insert_inode_hash(inode, inode->i_ino);
1480}
1481
1482extern struct file * get_empty_filp(void);
1483extern void file_move(struct file *f, struct list_head *list);
1484extern void file_kill(struct file *f);
1485struct bio;
1486extern void submit_bio(int, struct bio *);
1487extern int bdev_read_only(struct block_device *);
1488extern int set_blocksize(struct block_device *, int);
1489extern int sb_set_blocksize(struct super_block *, int);
1490extern int sb_min_blocksize(struct super_block *, int);
1491
1492extern int generic_file_mmap(struct file *, struct vm_area_struct *);
1493extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
1494extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1495extern int file_send_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1496extern ssize_t generic_file_read(struct file *, char __user *, size_t, loff_t *);
1497int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
1498extern ssize_t generic_file_write(struct file *, const char __user *, size_t, loff_t *);
1499extern ssize_t generic_file_aio_read(struct kiocb *, char __user *, size_t, loff_t);
1500extern ssize_t __generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t *);
1501extern ssize_t generic_file_aio_write(struct kiocb *, const char __user *, size_t, loff_t);
1502extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
1503 unsigned long, loff_t *);
1504extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
1505 unsigned long *, loff_t, loff_t *, size_t, size_t);
1506extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
1507 unsigned long, loff_t, loff_t *, size_t, ssize_t);
1508extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
1509extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
1510ssize_t generic_file_write_nolock(struct file *file, const struct iovec *iov,
1511 unsigned long nr_segs, loff_t *ppos);
1512extern ssize_t generic_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
1513extern void do_generic_mapping_read(struct address_space *mapping,
1514 struct file_ra_state *, struct file *,
1515 loff_t *, read_descriptor_t *, read_actor_t);
1516extern void
1517file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518extern ssize_t generic_file_readv(struct file *filp, const struct iovec *iov,
1519 unsigned long nr_segs, loff_t *ppos);
1520ssize_t generic_file_writev(struct file *filp, const struct iovec *iov,
1521 unsigned long nr_segs, loff_t *ppos);
1522extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
1523extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
1524extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
1525extern int generic_file_open(struct inode * inode, struct file * filp);
1526extern int nonseekable_open(struct inode * inode, struct file * filp);
1527
Carsten Otteceffc072005-06-23 22:05:25 -07001528#ifdef CONFIG_FS_XIP
Carsten Otteeb6fe0c2005-06-23 22:05:28 -07001529extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
1530 loff_t *ppos);
Carsten Otteceffc072005-06-23 22:05:25 -07001531extern ssize_t xip_file_sendfile(struct file *in_file, loff_t *ppos,
1532 size_t count, read_actor_t actor,
1533 void *target);
1534extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
Carsten Otteeb6fe0c2005-06-23 22:05:28 -07001535extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
1536 size_t len, loff_t *ppos);
Carsten Otteceffc072005-06-23 22:05:25 -07001537extern int xip_truncate_page(struct address_space *mapping, loff_t from);
Carsten Otte6d791252005-06-23 22:05:26 -07001538#else
1539static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
1540{
1541 return 0;
1542}
Carsten Otteceffc072005-06-23 22:05:25 -07001543#endif
1544
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545static inline void do_generic_file_read(struct file * filp, loff_t *ppos,
1546 read_descriptor_t * desc,
1547 read_actor_t actor)
1548{
1549 do_generic_mapping_read(filp->f_mapping,
1550 &filp->f_ra,
1551 filp,
1552 ppos,
1553 desc,
1554 actor);
1555}
1556
1557ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
1558 struct block_device *bdev, const struct iovec *iov, loff_t offset,
1559 unsigned long nr_segs, get_blocks_t get_blocks, dio_iodone_t end_io,
1560 int lock_type);
1561
1562enum {
1563 DIO_LOCKING = 1, /* need locking between buffered and direct access */
1564 DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */
1565 DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */
1566};
1567
1568static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
1569 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1570 loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
1571 dio_iodone_t end_io)
1572{
1573 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1574 nr_segs, get_blocks, end_io, DIO_LOCKING);
1575}
1576
1577static inline ssize_t blockdev_direct_IO_no_locking(int rw, struct kiocb *iocb,
1578 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1579 loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
1580 dio_iodone_t end_io)
1581{
1582 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1583 nr_segs, get_blocks, end_io, DIO_NO_LOCKING);
1584}
1585
1586static inline ssize_t blockdev_direct_IO_own_locking(int rw, struct kiocb *iocb,
1587 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1588 loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
1589 dio_iodone_t end_io)
1590{
1591 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1592 nr_segs, get_blocks, end_io, DIO_OWN_LOCKING);
1593}
1594
1595extern struct file_operations generic_ro_fops;
1596
1597#define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
1598
1599extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
1600extern int vfs_follow_link(struct nameidata *, const char *);
1601extern int page_readlink(struct dentry *, char __user *, int);
Linus Torvaldscc314ee2005-08-19 18:02:56 -07001602extern void *page_follow_link_light(struct dentry *, struct nameidata *);
1603extern void page_put_link(struct dentry *, struct nameidata *, void *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001604extern int page_symlink(struct inode *inode, const char *symname, int len);
1605extern struct inode_operations page_symlink_inode_operations;
1606extern int generic_readlink(struct dentry *, char __user *, int);
1607extern void generic_fillattr(struct inode *, struct kstat *);
1608extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1609void inode_add_bytes(struct inode *inode, loff_t bytes);
1610void inode_sub_bytes(struct inode *inode, loff_t bytes);
1611loff_t inode_get_bytes(struct inode *inode);
1612void inode_set_bytes(struct inode *inode, loff_t bytes);
1613
1614extern int vfs_readdir(struct file *, filldir_t, void *);
1615
1616extern int vfs_stat(char __user *, struct kstat *);
1617extern int vfs_lstat(char __user *, struct kstat *);
1618extern int vfs_fstat(unsigned int, struct kstat *);
1619
1620extern int vfs_ioctl(struct file *, unsigned int, unsigned int, unsigned long);
1621
1622extern struct file_system_type *get_fs_type(const char *name);
1623extern struct super_block *get_super(struct block_device *);
1624extern struct super_block *user_get_super(dev_t);
1625extern void drop_super(struct super_block *sb);
1626
1627extern int dcache_dir_open(struct inode *, struct file *);
1628extern int dcache_dir_close(struct inode *, struct file *);
1629extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
1630extern int dcache_readdir(struct file *, void *, filldir_t);
1631extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1632extern int simple_statfs(struct super_block *, struct kstatfs *);
1633extern int simple_link(struct dentry *, struct inode *, struct dentry *);
1634extern int simple_unlink(struct inode *, struct dentry *);
1635extern int simple_rmdir(struct inode *, struct dentry *);
1636extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1637extern int simple_sync_file(struct file *, struct dentry *, int);
1638extern int simple_empty(struct dentry *);
1639extern int simple_readpage(struct file *file, struct page *page);
1640extern int simple_prepare_write(struct file *file, struct page *page,
1641 unsigned offset, unsigned to);
1642extern int simple_commit_write(struct file *file, struct page *page,
1643 unsigned offset, unsigned to);
1644
1645extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
1646extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
1647extern struct file_operations simple_dir_operations;
1648extern struct inode_operations simple_dir_inode_operations;
1649struct tree_descr { char *name; struct file_operations *ops; int mode; };
1650struct dentry *d_alloc_name(struct dentry *, const char *);
1651extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
1652extern int simple_pin_fs(char *name, struct vfsmount **mount, int *count);
1653extern void simple_release_fs(struct vfsmount **mount, int *count);
1654
1655extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t);
1656
1657extern int inode_change_ok(struct inode *, struct iattr *);
1658extern int __must_check inode_setattr(struct inode *, struct iattr *);
1659
1660extern void inode_update_time(struct inode *inode, int ctime_too);
1661
1662static inline ino_t parent_ino(struct dentry *dentry)
1663{
1664 ino_t res;
1665
1666 spin_lock(&dentry->d_lock);
1667 res = dentry->d_parent->d_inode->i_ino;
1668 spin_unlock(&dentry->d_lock);
1669 return res;
1670}
1671
1672/* kernel/fork.c */
1673extern int unshare_files(void);
1674
1675/* Transaction based IO helpers */
1676
1677/*
1678 * An argresp is stored in an allocated page and holds the
1679 * size of the argument or response, along with its content
1680 */
1681struct simple_transaction_argresp {
1682 ssize_t size;
1683 char data[0];
1684};
1685
1686#define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
1687
1688char *simple_transaction_get(struct file *file, const char __user *buf,
1689 size_t size);
1690ssize_t simple_transaction_read(struct file *file, char __user *buf,
1691 size_t size, loff_t *pos);
1692int simple_transaction_release(struct inode *inode, struct file *file);
1693
1694static inline void simple_transaction_set(struct file *file, size_t n)
1695{
1696 struct simple_transaction_argresp *ar = file->private_data;
1697
1698 BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
1699
1700 /*
1701 * The barrier ensures that ar->size will really remain zero until
1702 * ar->data is ready for reading.
1703 */
1704 smp_mb();
1705 ar->size = n;
1706}
1707
Arnd Bergmannacaefc22005-05-18 14:40:59 +02001708/*
1709 * simple attribute files
1710 *
1711 * These attributes behave similar to those in sysfs:
1712 *
1713 * Writing to an attribute immediately sets a value, an open file can be
1714 * written to multiple times.
1715 *
1716 * Reading from an attribute creates a buffer from the value that might get
1717 * read with multiple read calls. When the attribute has been read
1718 * completely, no further read calls are possible until the file is opened
1719 * again.
1720 *
1721 * All attributes contain a text representation of a numeric value
1722 * that are accessed with the get() and set() functions.
1723 */
1724#define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
1725static int __fops ## _open(struct inode *inode, struct file *file) \
1726{ \
1727 __simple_attr_check_format(__fmt, 0ull); \
1728 return simple_attr_open(inode, file, __get, __set, __fmt); \
1729} \
1730static struct file_operations __fops = { \
1731 .owner = THIS_MODULE, \
1732 .open = __fops ## _open, \
1733 .release = simple_attr_close, \
1734 .read = simple_attr_read, \
1735 .write = simple_attr_write, \
1736};
1737
1738static inline void __attribute__((format(printf, 1, 2)))
1739__simple_attr_check_format(const char *fmt, ...)
1740{
1741 /* don't do anything, just let the compiler check the arguments; */
1742}
1743
1744int simple_attr_open(struct inode *inode, struct file *file,
1745 u64 (*get)(void *), void (*set)(void *, u64),
1746 const char *fmt);
1747int simple_attr_close(struct inode *inode, struct file *file);
1748ssize_t simple_attr_read(struct file *file, char __user *buf,
1749 size_t len, loff_t *ppos);
1750ssize_t simple_attr_write(struct file *file, const char __user *buf,
1751 size_t len, loff_t *ppos);
1752
1753
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754#ifdef CONFIG_SECURITY
1755static inline char *alloc_secdata(void)
1756{
1757 return (char *)get_zeroed_page(GFP_KERNEL);
1758}
1759
1760static inline void free_secdata(void *secdata)
1761{
1762 free_page((unsigned long)secdata);
1763}
1764#else
1765static inline char *alloc_secdata(void)
1766{
1767 return (char *)1;
1768}
1769
1770static inline void free_secdata(void *secdata)
1771{ }
1772#endif /* CONFIG_SECURITY */
1773
1774#endif /* __KERNEL__ */
1775#endif /* _LINUX_FS_H */