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1da177e4
LT
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: */
32struct files_stat_struct {
33 int nr_files; /* read only */
34 int nr_free_files; /* read only */
35 int max_files; /* tunable */
36};
37extern struct files_stat_struct files_stat;
38
39struct inodes_stat_t {
40 int nr_inodes;
41 int nr_unused;
42 int dummy[5];
43};
44extern struct inodes_stat_t inodes_stat;
45
46extern int leases_enable, lease_break_time;
47
48#ifdef CONFIG_DNOTIFY
49extern 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 */
a7662236 72#define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */
1da177e4
LT
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. -- rmk@arm.uk.linux.org
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>
22e2c507 217#include <linux/sched.h>
1da177e4
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218
219#include <asm/atomic.h>
220#include <asm/semaphore.h>
221#include <asm/byteorder.h>
222
223struct iovec;
224struct nameidata;
92198f7e 225struct kiocb;
1da177e4
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226struct pipe_inode_info;
227struct poll_table_struct;
228struct kstatfs;
229struct vm_area_struct;
230struct vfsmount;
231
232/* Used to be a macro which just called the function, now just a function */
233extern void update_atime (struct inode *);
234
235extern void __init inode_init(unsigned long);
236extern void __init inode_init_early(void);
237extern void __init mnt_init(unsigned long);
238extern void __init files_init(unsigned long);
239
240struct buffer_head;
241typedef int (get_block_t)(struct inode *inode, sector_t iblock,
242 struct buffer_head *bh_result, int create);
243typedef int (get_blocks_t)(struct inode *inode, sector_t iblock,
244 unsigned long max_blocks,
245 struct buffer_head *bh_result, int create);
92198f7e 246typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
1da177e4
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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 <warlord@MIT.EDU> 94-10-20
275 */
276struct 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;
1da177e4
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285};
286
1da177e4
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287/*
288 * Includes for diskquotas.
289 */
290#include <linux/quota.h>
291
292/*
293 * oh the beauties of C type declarations.
294 */
295struct page;
296struct address_space;
297struct writeback_control;
1da177e4
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298
299struct 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);
ceffc078
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325 struct page* (*get_xip_page)(struct address_space *, sector_t,
326 int);
1da177e4
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327};
328
329struct backing_dev_info;
330struct 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
354struct 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
388int mapping_tagged(struct address_space *mapping, int tag);
389
390/*
391 * Might pages of this file be mapped into userspace?
392 */
393static 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 */
405static 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
421struct 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
0eeca283
RL
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
1da177e4
LT
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 */
498static 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
522static 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
537static inline unsigned iminor(struct inode *inode)
538{
539 return MINOR(inode->i_rdev);
540}
541
542static inline unsigned imajor(struct inode *inode)
543{
544 return MAJOR(inode->i_rdev);
545}
546
547extern struct block_device *I_BDEV(struct inode *inode);
548
549struct 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 */
560struct 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
575struct 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;
1da177e4
LT
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
1da177e4
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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};
601extern 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 */
632typedef struct files_struct *fl_owner_t;
633
634struct 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
641struct 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
654struct 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;
8d0a8a9d 674 struct nfs4_lock_info nfs4_fl;
1da177e4
LT
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
685extern struct list_head file_lock_list;
686
687#include <linux/fcntl.h>
688
689extern int fcntl_getlk(struct file *, struct flock __user *);
c293621b
PS
690extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
691 struct flock __user *);
1da177e4
LT
692
693#if BITS_PER_LONG == 32
694extern int fcntl_getlk64(struct file *, struct flock64 __user *);
c293621b
PS
695extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
696 struct flock64 __user *);
1da177e4
LT
697#endif
698
699extern void send_sigio(struct fown_struct *fown, int fd, int band);
700extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
701extern int fcntl_getlease(struct file *filp);
702
703/* fs/locks.c */
704extern void locks_init_lock(struct file_lock *);
705extern void locks_copy_lock(struct file_lock *, struct file_lock *);
706extern void locks_remove_posix(struct file *, fl_owner_t);
707extern void locks_remove_flock(struct file *);
708extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
709extern int posix_lock_file(struct file *, struct file_lock *);
710extern int posix_lock_file_wait(struct file *, struct file_lock *);
711extern void posix_block_lock(struct file_lock *, struct file_lock *);
712extern void posix_unblock_lock(struct file *, struct file_lock *);
713extern int posix_locks_deadlock(struct file_lock *, struct file_lock *);
714extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
715extern int __break_lease(struct inode *inode, unsigned int flags);
716extern void lease_get_mtime(struct inode *, struct timespec *time);
717extern int setlease(struct file *, long, struct file_lock **);
718extern int lease_modify(struct file_lock **, int);
719extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
720extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
721extern void steal_locks(fl_owner_t from);
722
723struct 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: */
733extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
734/* can be called from interrupts */
735extern void kill_fasync(struct fasync_struct **, int, int);
736/* only for net: no internal synchronization */
737extern void __kill_fasync(struct fasync_struct *, int, int);
738
739extern int f_setown(struct file *filp, unsigned long arg, int force);
740extern void f_delown(struct file *filp);
741extern 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
751extern struct list_head super_blocks;
752extern spinlock_t sb_lock;
753
754#define sb_entry(list) list_entry((list), struct super_block, s_list)
755#define S_BIAS (1<<30)
756struct 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
809extern struct timespec current_fs_time(struct super_block *sb);
810
811/*
812 * Snapshotting support.
813 */
814enum {
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
22e2c507
JA
823static inline void get_fs_excl(void)
824{
825 atomic_inc(&current->fs_excl);
826}
827
828static inline void put_fs_excl(void)
829{
830 atomic_dec(&current->fs_excl);
831}
832
833static inline int has_fs_excl(void)
834{
835 return atomic_read(&current->fs_excl);
836}
837
838
1da177e4
LT
839/*
840 * Superblock locking.
841 */
842static inline void lock_super(struct super_block * sb)
843{
22e2c507 844 get_fs_excl();
1da177e4
LT
845 down(&sb->s_lock);
846}
847
848static inline void unlock_super(struct super_block * sb)
849{
22e2c507 850 put_fs_excl();
1da177e4
LT
851 up(&sb->s_lock);
852}
853
854/*
855 * VFS helper functions..
856 */
857extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
858extern int vfs_mkdir(struct inode *, struct dentry *, int);
859extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
860extern int vfs_symlink(struct inode *, struct dentry *, const char *, int);
861extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
862extern int vfs_rmdir(struct inode *, struct dentry *);
863extern int vfs_unlink(struct inode *, struct dentry *);
864extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
865
866/*
867 * VFS dentry helper functions.
868 */
869extern 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)
890int 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 */
898typedef int (*filldir_t)(void *, const char *, int, loff_t, ino_t, unsigned);
899
900struct 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);
bb93e3a5 904 long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
1da177e4 905 long (*compat_ioctl) (struct file *, unsigned, unsigned long);
420edbcc 906 int (*direct_access) (struct block_device *, sector_t, unsigned long *);
1da177e4
LT
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 */
921typedef 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
931typedef 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 */
944struct 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
974struct 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);
cc314eef
LT
986 void * (*follow_link) (struct dentry *, struct nameidata *);
987 void (*put_link) (struct dentry *, struct nameidata *, void *);
1da177e4
LT
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
998struct seq_file;
999
1000extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1001extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1002extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1003 unsigned long, loff_t *);
1004extern 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 */
1011struct 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
991114c6 1047#define I_WILL_FREE 128
1da177e4
LT
1048
1049#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1050
1051extern void __mark_inode_dirty(struct inode *, int);
1052static inline void mark_inode_dirty(struct inode *inode)
1053{
1054 __mark_inode_dirty(inode, I_DIRTY);
1055}
1056
1057static inline void mark_inode_dirty_sync(struct inode *inode)
1058{
1059 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1060}
1061
1062static 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
1068static 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
1074int sync_inode(struct inode *inode, struct writeback_control *wbc);
1075
1076/**
4dc3b16b
PP
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
1da177e4
LT
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 *
67be2dd1
MW
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.
1da177e4
LT
1093 *
1094 * nfsd encodes information use to determine which filesystem a filehandle
67be2dd1
MW
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.
1da177e4
LT
1100 *
1101 * In some situations, nfsd needs to get a dentry which is connected into a
67be2dd1
MW
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.
1da177e4
LT
1108 *
1109 * decode_fh:
67be2dd1
MW
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).
1da177e4
LT
1118 *
1119 * encode_fh:
67be2dd1
MW
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
1da177e4
LT
1128 *
1129 * get_name:
67be2dd1
MW
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.
1da177e4
LT
1135 *
1136 * get_parent:
67be2dd1
MW
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.
1da177e4
LT
1140 *
1141 * get_dentry:
67be2dd1
MW
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.
1da177e4 1150 *
67be2dd1
MW
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.
1da177e4
LT
1154 *
1155 * Locking rules:
67be2dd1
MW
1156 * get_parent is called with child->d_inode->i_sem down
1157 * get_name is not (which is possibly inconsistent)
1da177e4
LT
1158 */
1159
1160struct 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
1182extern struct dentry *
1183find_exported_dentry(struct super_block *sb, void *obj, void *parent,
1184 int (*acceptable)(void *context, struct dentry *de),
1185 void *context);
1186
1187struct 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
1198struct 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));
1201struct 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));
1204struct 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));
1207void generic_shutdown_super(struct super_block *sb);
1208void kill_block_super(struct super_block *sb);
1209void kill_anon_super(struct super_block *sb);
1210void kill_litter_super(struct super_block *sb);
1211void deactivate_super(struct super_block *sb);
1212int set_anon_super(struct super_block *s, void *data);
1213struct 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);
1217struct super_block *get_sb_pseudo(struct file_system_type *, char *,
1218 struct super_operations *ops, unsigned long);
1219int __put_super(struct super_block *sb);
1220int __put_super_and_need_restart(struct super_block *sb);
1221void 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
1229extern int register_filesystem(struct file_system_type *);
1230extern int unregister_filesystem(struct file_system_type *);
1231extern struct vfsmount *kern_mount(struct file_system_type *);
1232extern int may_umount_tree(struct vfsmount *);
1233extern int may_umount(struct vfsmount *);
1234extern long do_mount(char *, char *, char *, unsigned long, void *);
1235
1236extern int vfs_statfs(struct super_block *, struct kstatfs *);
1237
1238#define FLOCK_VERIFY_READ 1
1239#define FLOCK_VERIFY_WRITE 2
1240
1241extern int locks_mandatory_locked(struct inode *);
1242extern 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
1251static 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
1258extern int rw_verify_area(int, struct file *, loff_t *, size_t);
1259
1260static 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
1274static 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
1283extern int do_truncate(struct dentry *, loff_t start);
e922efc3 1284extern long do_sys_open(const char __user *filename, int flags, int mode);
1da177e4
LT
1285extern struct file *filp_open(const char *, int, int);
1286extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
1287extern int filp_close(struct file *, fl_owner_t id);
1288extern char * getname(const char __user *);
1289
1290/* fs/dcache.c */
1291extern void __init vfs_caches_init_early(void);
1292extern 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
1299extern void putname(const char *name);
1300#endif
1301
1302extern int register_blkdev(unsigned int, const char *);
1303extern int unregister_blkdev(unsigned int, const char *);
1304extern struct block_device *bdget(dev_t);
1305extern void bd_set_size(struct block_device *, loff_t size);
1306extern void bd_forget(struct inode *inode);
1307extern void bdput(struct block_device *);
1308extern struct block_device *open_by_devnum(dev_t, unsigned);
1309extern struct file_operations def_blk_fops;
1310extern struct address_space_operations def_blk_aops;
1311extern struct file_operations def_chr_fops;
1312extern struct file_operations bad_sock_fops;
1313extern struct file_operations def_fifo_fops;
1314extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
1315extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
1316extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
1317extern int blkdev_get(struct block_device *, mode_t, unsigned);
1318extern int blkdev_put(struct block_device *);
1319extern int bd_claim(struct block_device *, void *);
1320extern void bd_release(struct block_device *);
1321
1322/* fs/char_dev.c */
1323extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
1324extern int register_chrdev_region(dev_t, unsigned, const char *);
1325extern int register_chrdev(unsigned int, const char *,
1326 struct file_operations *);
1327extern int unregister_chrdev(unsigned int, const char *);
1328extern void unregister_chrdev_region(dev_t, unsigned);
1329extern int chrdev_open(struct inode *, struct file *);
1330
1331/* fs/block_dev.c */
1332#define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
1333extern const char *__bdevname(dev_t, char *buffer);
1334extern const char *bdevname(struct block_device *bdev, char *buffer);
1335extern struct block_device *lookup_bdev(const char *);
1336extern struct block_device *open_bdev_excl(const char *, int, void *);
1337extern void close_bdev_excl(struct block_device *);
1338
1339extern void init_special_inode(struct inode *, umode_t, dev_t);
1340
1341/* Invalid inode operations -- fs/bad_inode.c */
1342extern void make_bad_inode(struct inode *);
1343extern int is_bad_inode(struct inode *);
1344
1345extern struct file_operations read_fifo_fops;
1346extern struct file_operations write_fifo_fops;
1347extern struct file_operations rdwr_fifo_fops;
1348extern struct file_operations read_pipe_fops;
1349extern struct file_operations write_pipe_fops;
1350extern struct file_operations rdwr_pipe_fops;
1351
1352extern 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
1364extern int check_disk_change(struct block_device *);
1365extern int invalidate_inodes(struct super_block *);
2ef41634 1366extern int __invalidate_device(struct block_device *);
1da177e4
LT
1367extern int invalidate_partition(struct gendisk *, int);
1368unsigned long invalidate_mapping_pages(struct address_space *mapping,
1369 pgoff_t start, pgoff_t end);
1370unsigned long invalidate_inode_pages(struct address_space *mapping);
1371static 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}
1377extern int invalidate_inode_pages2(struct address_space *mapping);
1378extern int invalidate_inode_pages2_range(struct address_space *mapping,
1379 pgoff_t start, pgoff_t end);
1380extern int write_inode_now(struct inode *, int);
1381extern int filemap_fdatawrite(struct address_space *);
1382extern int filemap_flush(struct address_space *);
1383extern int filemap_fdatawait(struct address_space *);
1384extern int filemap_write_and_wait(struct address_space *mapping);
1385extern int filemap_write_and_wait_range(struct address_space *mapping,
1386 loff_t lstart, loff_t lend);
1387extern void sync_supers(void);
1388extern void sync_filesystems(int wait);
1389extern void emergency_sync(void);
1390extern void emergency_remount(void);
1391extern int do_remount_sb(struct super_block *sb, int flags,
1392 void *data, int force);
1393extern sector_t bmap(struct inode *, sector_t);
1da177e4
LT
1394extern int notify_change(struct dentry *, struct iattr *);
1395extern int permission(struct inode *, int, struct nameidata *);
1396extern int generic_permission(struct inode *, int,
1397 int (*check_acl)(struct inode *, int));
1398
1399extern int get_write_access(struct inode *);
1400extern int deny_write_access(struct file *);
1401static inline void put_write_access(struct inode * inode)
1402{
1403 atomic_dec(&inode->i_writecount);
1404}
1405static inline void allow_write_access(struct file *file)
1406{
1407 if (file)
1408 atomic_inc(&file->f_dentry->d_inode->i_writecount);
1409}
1410extern int do_pipe(int *);
1411
1412extern int open_namei(const char *, int, int, struct nameidata *);
1413extern int may_open(struct nameidata *, int, int);
1414
1415extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
1416extern struct file * open_exec(const char *);
1417
1418/* fs/dcache.c -- generic fs support functions */
1419extern int is_subdir(struct dentry *, struct dentry *);
1420extern ino_t find_inode_number(struct dentry *, struct qstr *);
1421
1422#include <linux/err.h>
1423
1424/* needed for stackable file system support */
1425extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
1426
1427extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
1428
1429extern void inode_init_once(struct inode *);
1430extern void iput(struct inode *);
1431extern struct inode * igrab(struct inode *);
1432extern ino_t iunique(struct super_block *, ino_t);
1433extern int inode_needs_sync(struct inode *inode);
1434extern void generic_delete_inode(struct inode *inode);
cb2c0233 1435extern void generic_drop_inode(struct inode *inode);
1da177e4 1436
88bd5121
AA
1437extern struct inode *ilookup5_nowait(struct super_block *sb,
1438 unsigned long hashval, int (*test)(struct inode *, void *),
1439 void *data);
1da177e4
LT
1440extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
1441 int (*test)(struct inode *, void *), void *data);
1442extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
1443
1444extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
1445extern struct inode * iget_locked(struct super_block *, unsigned long);
1446extern void unlock_new_inode(struct inode *);
1447
1448static 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
1460extern void __iget(struct inode * inode);
1461extern void clear_inode(struct inode *);
1462extern void destroy_inode(struct inode *);
1463extern struct inode *new_inode(struct super_block *);
1464extern int remove_suid(struct dentry *);
1465extern void remove_dquot_ref(struct super_block *, int, struct list_head *);
1466extern struct semaphore iprune_sem;
1467
1468extern void __insert_inode_hash(struct inode *, unsigned long hashval);
1469extern void remove_inode_hash(struct inode *);
1470static inline void insert_inode_hash(struct inode *inode) {
1471 __insert_inode_hash(inode, inode->i_ino);
1472}
1473
1474extern struct file * get_empty_filp(void);
1475extern void file_move(struct file *f, struct list_head *list);
1476extern void file_kill(struct file *f);
1477struct bio;
1478extern void submit_bio(int, struct bio *);
1479extern int bdev_read_only(struct block_device *);
1480extern int set_blocksize(struct block_device *, int);
1481extern int sb_set_blocksize(struct super_block *, int);
1482extern int sb_min_blocksize(struct super_block *, int);
1483
1484extern int generic_file_mmap(struct file *, struct vm_area_struct *);
1485extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
1486extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1487extern int file_send_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1488extern ssize_t generic_file_read(struct file *, char __user *, size_t, loff_t *);
1489int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
1490extern ssize_t generic_file_write(struct file *, const char __user *, size_t, loff_t *);
1491extern ssize_t generic_file_aio_read(struct kiocb *, char __user *, size_t, loff_t);
1492extern ssize_t __generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t *);
1493extern ssize_t generic_file_aio_write(struct kiocb *, const char __user *, size_t, loff_t);
1494extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
1495 unsigned long, loff_t *);
1496extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
1497 unsigned long *, loff_t, loff_t *, size_t, size_t);
1498extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
1499 unsigned long, loff_t, loff_t *, size_t, ssize_t);
1500extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
1501extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
1502ssize_t generic_file_write_nolock(struct file *file, const struct iovec *iov,
1503 unsigned long nr_segs, loff_t *ppos);
1504extern ssize_t generic_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
1505extern 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);
1508extern void
1509file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
1510extern ssize_t generic_file_direct_IO(int rw, struct kiocb *iocb,
1511 const struct iovec *iov, loff_t offset, unsigned long nr_segs);
1512extern ssize_t generic_file_readv(struct file *filp, const struct iovec *iov,
1513 unsigned long nr_segs, loff_t *ppos);
1514ssize_t generic_file_writev(struct file *filp, const struct iovec *iov,
1515 unsigned long nr_segs, loff_t *ppos);
1516extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
1517extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
1518extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
1519extern int generic_file_open(struct inode * inode, struct file * filp);
1520extern int nonseekable_open(struct inode * inode, struct file * filp);
1521
ceffc078 1522#ifdef CONFIG_FS_XIP
eb6fe0c3
CO
1523extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
1524 loff_t *ppos);
ceffc078
CO
1525extern ssize_t xip_file_sendfile(struct file *in_file, loff_t *ppos,
1526 size_t count, read_actor_t actor,
1527 void *target);
1528extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
eb6fe0c3
CO
1529extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
1530 size_t len, loff_t *ppos);
ceffc078 1531extern int xip_truncate_page(struct address_space *mapping, loff_t from);
6d79125b
CO
1532#else
1533static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
1534{
1535 return 0;
1536}
ceffc078
CO
1537#endif
1538
1da177e4
LT
1539static 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
1551ssize_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
1556enum {
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
1562static 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
1571static 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
1580static 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
1589extern 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
1593extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
1594extern int vfs_follow_link(struct nameidata *, const char *);
1595extern int page_readlink(struct dentry *, char __user *, int);
cc314eef
LT
1596extern void *page_follow_link_light(struct dentry *, struct nameidata *);
1597extern void page_put_link(struct dentry *, struct nameidata *, void *);
1da177e4
LT
1598extern int page_symlink(struct inode *inode, const char *symname, int len);
1599extern struct inode_operations page_symlink_inode_operations;
1600extern int generic_readlink(struct dentry *, char __user *, int);
1601extern void generic_fillattr(struct inode *, struct kstat *);
1602extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1603void inode_add_bytes(struct inode *inode, loff_t bytes);
1604void inode_sub_bytes(struct inode *inode, loff_t bytes);
1605loff_t inode_get_bytes(struct inode *inode);
1606void inode_set_bytes(struct inode *inode, loff_t bytes);
1607
1608extern int vfs_readdir(struct file *, filldir_t, void *);
1609
1610extern int vfs_stat(char __user *, struct kstat *);
1611extern int vfs_lstat(char __user *, struct kstat *);
1612extern int vfs_fstat(unsigned int, struct kstat *);
1613
1614extern int vfs_ioctl(struct file *, unsigned int, unsigned int, unsigned long);
1615
1616extern struct file_system_type *get_fs_type(const char *name);
1617extern struct super_block *get_super(struct block_device *);
1618extern struct super_block *user_get_super(dev_t);
1619extern void drop_super(struct super_block *sb);
1620
1621extern int dcache_dir_open(struct inode *, struct file *);
1622extern int dcache_dir_close(struct inode *, struct file *);
1623extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
1624extern int dcache_readdir(struct file *, void *, filldir_t);
1625extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1626extern int simple_statfs(struct super_block *, struct kstatfs *);
1627extern int simple_link(struct dentry *, struct inode *, struct dentry *);
1628extern int simple_unlink(struct inode *, struct dentry *);
1629extern int simple_rmdir(struct inode *, struct dentry *);
1630extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1631extern int simple_sync_file(struct file *, struct dentry *, int);
1632extern int simple_empty(struct dentry *);
1633extern int simple_readpage(struct file *file, struct page *page);
1634extern int simple_prepare_write(struct file *file, struct page *page,
1635 unsigned offset, unsigned to);
1636extern int simple_commit_write(struct file *file, struct page *page,
1637 unsigned offset, unsigned to);
1638
1639extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
1640extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
1641extern struct file_operations simple_dir_operations;
1642extern struct inode_operations simple_dir_inode_operations;
1643struct tree_descr { char *name; struct file_operations *ops; int mode; };
1644struct dentry *d_alloc_name(struct dentry *, const char *);
1645extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
1646extern int simple_pin_fs(char *name, struct vfsmount **mount, int *count);
1647extern void simple_release_fs(struct vfsmount **mount, int *count);
1648
1649extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t);
1650
1651extern int inode_change_ok(struct inode *, struct iattr *);
1652extern int __must_check inode_setattr(struct inode *, struct iattr *);
1653
1654extern void inode_update_time(struct inode *inode, int ctime_too);
1655
1656static 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 */
1667extern 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 */
1675struct 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
1682char *simple_transaction_get(struct file *file, const char __user *buf,
1683 size_t size);
1684ssize_t simple_transaction_read(struct file *file, char __user *buf,
1685 size_t size, loff_t *pos);
1686int simple_transaction_release(struct inode *inode, struct file *file);
1687
1688static 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
acaefc25
AB
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) \
1719static 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} \
1724static 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
1732static 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
1738int simple_attr_open(struct inode *inode, struct file *file,
1739 u64 (*get)(void *), void (*set)(void *, u64),
1740 const char *fmt);
1741int simple_attr_close(struct inode *inode, struct file *file);
1742ssize_t simple_attr_read(struct file *file, char __user *buf,
1743 size_t len, loff_t *ppos);
1744ssize_t simple_attr_write(struct file *file, const char __user *buf,
1745 size_t len, loff_t *ppos);
1746
1747
1da177e4
LT
1748#ifdef CONFIG_SECURITY
1749static inline char *alloc_secdata(void)
1750{
1751 return (char *)get_zeroed_page(GFP_KERNEL);
1752}
1753
1754static inline void free_secdata(void *secdata)
1755{
1756 free_page((unsigned long)secdata);
1757}
1758#else
1759static inline char *alloc_secdata(void)
1760{
1761 return (char *)1;
1762}
1763
1764static inline void free_secdata(void *secdata)
1765{ }
1766#endif /* CONFIG_SECURITY */
1767
1768#endif /* __KERNEL__ */
1769#endif /* _LINUX_FS_H */