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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>
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 */
72#define SPECIAL 4 /* For non-blockdevice requests in request queue */
73#define READ_SYNC (READ | (1 << BIO_RW_SYNC))
74#define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC))
75#define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
76
77#define SEL_IN 1
78#define SEL_OUT 2
79#define SEL_EX 4
80
81/* public flags for file_system_type */
82#define FS_REQUIRES_DEV 1
83#define FS_BINARY_MOUNTDATA 2
84#define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
85#define FS_ODD_RENAME 32768 /* Temporary stuff; will go away as soon
86 * as nfs_rename() will be cleaned up
87 */
88/*
89 * These are the fs-independent mount-flags: up to 32 flags are supported
90 */
91#define MS_RDONLY 1 /* Mount read-only */
92#define MS_NOSUID 2 /* Ignore suid and sgid bits */
93#define MS_NODEV 4 /* Disallow access to device special files */
94#define MS_NOEXEC 8 /* Disallow program execution */
95#define MS_SYNCHRONOUS 16 /* Writes are synced at once */
96#define MS_REMOUNT 32 /* Alter flags of a mounted FS */
97#define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
98#define MS_DIRSYNC 128 /* Directory modifications are synchronous */
99#define MS_NOATIME 1024 /* Do not update access times. */
100#define MS_NODIRATIME 2048 /* Do not update directory access times */
101#define MS_BIND 4096
102#define MS_MOVE 8192
103#define MS_REC 16384
104#define MS_VERBOSE 32768
105#define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
106#define MS_ACTIVE (1<<30)
107#define MS_NOUSER (1<<31)
108
109/*
110 * Superblock flags that can be altered by MS_REMOUNT
111 */
112#define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_NOATIME|\
113 MS_NODIRATIME)
114
115/*
116 * Old magic mount flag and mask
117 */
118#define MS_MGC_VAL 0xC0ED0000
119#define MS_MGC_MSK 0xffff0000
120
121/* Inode flags - they have nothing to superblock flags now */
122
123#define S_SYNC 1 /* Writes are synced at once */
124#define S_NOATIME 2 /* Do not update access times */
125#define S_APPEND 4 /* Append-only file */
126#define S_IMMUTABLE 8 /* Immutable file */
127#define S_DEAD 16 /* removed, but still open directory */
128#define S_NOQUOTA 32 /* Inode is not counted to quota */
129#define S_DIRSYNC 64 /* Directory modifications are synchronous */
130#define S_NOCMTIME 128 /* Do not update file c/mtime */
131#define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
132#define S_PRIVATE 512 /* Inode is fs-internal */
133
134/*
135 * Note that nosuid etc flags are inode-specific: setting some file-system
136 * flags just means all the inodes inherit those flags by default. It might be
137 * possible to override it selectively if you really wanted to with some
138 * ioctl() that is not currently implemented.
139 *
140 * Exception: MS_RDONLY is always applied to the entire file system.
141 *
142 * Unfortunately, it is possible to change a filesystems flags with it mounted
143 * with files in use. This means that all of the inodes will not have their
144 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
145 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
146 */
147#define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
148
149#define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
150#define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
151 ((inode)->i_flags & S_SYNC))
152#define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
153 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
154#define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
155
156#define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
157#define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
158#define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
159#define IS_NOATIME(inode) (__IS_FLG(inode, MS_NOATIME) || ((inode)->i_flags & S_NOATIME))
160#define IS_NODIRATIME(inode) __IS_FLG(inode, MS_NODIRATIME)
161#define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
162
163#define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
164#define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
165#define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
166#define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
167
168/* the read-only stuff doesn't really belong here, but any other place is
169 probably as bad and I don't want to create yet another include file. */
170
171#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
172#define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
173#define BLKRRPART _IO(0x12,95) /* re-read partition table */
174#define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
175#define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
176#define BLKRASET _IO(0x12,98) /* set read ahead for block device */
177#define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
178#define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
179#define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
180#define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
181#define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
182#define BLKSSZGET _IO(0x12,104)/* get block device sector size */
183#if 0
184#define BLKPG _IO(0x12,105)/* See blkpg.h */
185
186/* Some people are morons. Do not use sizeof! */
187
188#define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
189#define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
190/* This was here just to show that the number is taken -
191 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
192#endif
193/* A jump here: 108-111 have been used for various private purposes. */
194#define BLKBSZGET _IOR(0x12,112,size_t)
195#define BLKBSZSET _IOW(0x12,113,size_t)
196#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
197
198#define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
199#define FIBMAP _IO(0x00,1) /* bmap access */
200#define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
201
202#ifdef __KERNEL__
203
204#include <linux/linkage.h>
205#include <linux/wait.h>
206#include <linux/types.h>
207#include <linux/kdev_t.h>
208#include <linux/dcache.h>
209#include <linux/stat.h>
210#include <linux/cache.h>
211#include <linux/kobject.h>
212#include <linux/list.h>
213#include <linux/radix-tree.h>
214#include <linux/prio_tree.h>
215#include <linux/init.h>
216
217#include <asm/atomic.h>
218#include <asm/semaphore.h>
219#include <asm/byteorder.h>
220
221struct iovec;
222struct nameidata;
Christoph Hellwig92198f72005-06-23 22:00:59 -0700223struct kiocb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224struct pipe_inode_info;
225struct poll_table_struct;
226struct kstatfs;
227struct vm_area_struct;
228struct vfsmount;
229
230/* Used to be a macro which just called the function, now just a function */
231extern void update_atime (struct inode *);
232
233extern void __init inode_init(unsigned long);
234extern void __init inode_init_early(void);
235extern void __init mnt_init(unsigned long);
236extern void __init files_init(unsigned long);
237
238struct buffer_head;
239typedef int (get_block_t)(struct inode *inode, sector_t iblock,
240 struct buffer_head *bh_result, int create);
241typedef int (get_blocks_t)(struct inode *inode, sector_t iblock,
242 unsigned long max_blocks,
243 struct buffer_head *bh_result, int create);
Christoph Hellwig92198f72005-06-23 22:00:59 -0700244typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245 ssize_t bytes, void *private);
246
247/*
248 * Attribute flags. These should be or-ed together to figure out what
249 * has been changed!
250 */
251#define ATTR_MODE 1
252#define ATTR_UID 2
253#define ATTR_GID 4
254#define ATTR_SIZE 8
255#define ATTR_ATIME 16
256#define ATTR_MTIME 32
257#define ATTR_CTIME 64
258#define ATTR_ATIME_SET 128
259#define ATTR_MTIME_SET 256
260#define ATTR_FORCE 512 /* Not a change, but a change it */
261#define ATTR_ATTR_FLAG 1024
262#define ATTR_KILL_SUID 2048
263#define ATTR_KILL_SGID 4096
264
265/*
266 * This is the Inode Attributes structure, used for notify_change(). It
267 * uses the above definitions as flags, to know which values have changed.
268 * Also, in this manner, a Filesystem can look at only the values it cares
269 * about. Basically, these are the attributes that the VFS layer can
270 * request to change from the FS layer.
271 *
272 * Derek Atkins <warlord@MIT.EDU> 94-10-20
273 */
274struct iattr {
275 unsigned int ia_valid;
276 umode_t ia_mode;
277 uid_t ia_uid;
278 gid_t ia_gid;
279 loff_t ia_size;
280 struct timespec ia_atime;
281 struct timespec ia_mtime;
282 struct timespec ia_ctime;
283 unsigned int ia_attr_flags;
284};
285
286/*
287 * This is the inode attributes flag definitions
288 */
289#define ATTR_FLAG_SYNCRONOUS 1 /* Syncronous write */
290#define ATTR_FLAG_NOATIME 2 /* Don't update atime */
291#define ATTR_FLAG_APPEND 4 /* Append-only file */
292#define ATTR_FLAG_IMMUTABLE 8 /* Immutable file */
293#define ATTR_FLAG_NODIRATIME 16 /* Don't update atime for directory */
294
295/*
296 * Includes for diskquotas.
297 */
298#include <linux/quota.h>
299
300/*
301 * oh the beauties of C type declarations.
302 */
303struct page;
304struct address_space;
305struct writeback_control;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306
307struct address_space_operations {
308 int (*writepage)(struct page *page, struct writeback_control *wbc);
309 int (*readpage)(struct file *, struct page *);
310 int (*sync_page)(struct page *);
311
312 /* Write back some dirty pages from this mapping. */
313 int (*writepages)(struct address_space *, struct writeback_control *);
314
315 /* Set a page dirty */
316 int (*set_page_dirty)(struct page *page);
317
318 int (*readpages)(struct file *filp, struct address_space *mapping,
319 struct list_head *pages, unsigned nr_pages);
320
321 /*
322 * ext3 requires that a successful prepare_write() call be followed
323 * by a commit_write() call - they must be balanced
324 */
325 int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
326 int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
327 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
328 sector_t (*bmap)(struct address_space *, sector_t);
329 int (*invalidatepage) (struct page *, unsigned long);
330 int (*releasepage) (struct page *, int);
331 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
332 loff_t offset, unsigned long nr_segs);
Carsten Otteceffc072005-06-23 22:05:25 -0700333 struct page* (*get_xip_page)(struct address_space *, sector_t,
334 int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335};
336
337struct backing_dev_info;
338struct address_space {
339 struct inode *host; /* owner: inode, block_device */
340 struct radix_tree_root page_tree; /* radix tree of all pages */
341 rwlock_t tree_lock; /* and rwlock protecting it */
342 unsigned int i_mmap_writable;/* count VM_SHARED mappings */
343 struct prio_tree_root i_mmap; /* tree of private and shared mappings */
344 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
345 spinlock_t i_mmap_lock; /* protect tree, count, list */
346 unsigned int truncate_count; /* Cover race condition with truncate */
347 unsigned long nrpages; /* number of total pages */
348 pgoff_t writeback_index;/* writeback starts here */
349 struct address_space_operations *a_ops; /* methods */
350 unsigned long flags; /* error bits/gfp mask */
351 struct backing_dev_info *backing_dev_info; /* device readahead, etc */
352 spinlock_t private_lock; /* for use by the address_space */
353 struct list_head private_list; /* ditto */
354 struct address_space *assoc_mapping; /* ditto */
355} __attribute__((aligned(sizeof(long))));
356 /*
357 * On most architectures that alignment is already the case; but
358 * must be enforced here for CRIS, to let the least signficant bit
359 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
360 */
361
362struct block_device {
363 dev_t bd_dev; /* not a kdev_t - it's a search key */
364 struct inode * bd_inode; /* will die */
365 int bd_openers;
366 struct semaphore bd_sem; /* open/close mutex */
367 struct semaphore bd_mount_sem; /* mount mutex */
368 struct list_head bd_inodes;
369 void * bd_holder;
370 int bd_holders;
371 struct block_device * bd_contains;
372 unsigned bd_block_size;
373 struct hd_struct * bd_part;
374 /* number of times partitions within this device have been opened. */
375 unsigned bd_part_count;
376 int bd_invalidated;
377 struct gendisk * bd_disk;
378 struct list_head bd_list;
379 struct backing_dev_info *bd_inode_backing_dev_info;
380 /*
381 * Private data. You must have bd_claim'ed the block_device
382 * to use this. NOTE: bd_claim allows an owner to claim
383 * the same device multiple times, the owner must take special
384 * care to not mess up bd_private for that case.
385 */
386 unsigned long bd_private;
387};
388
389/*
390 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
391 * radix trees
392 */
393#define PAGECACHE_TAG_DIRTY 0
394#define PAGECACHE_TAG_WRITEBACK 1
395
396int mapping_tagged(struct address_space *mapping, int tag);
397
398/*
399 * Might pages of this file be mapped into userspace?
400 */
401static inline int mapping_mapped(struct address_space *mapping)
402{
403 return !prio_tree_empty(&mapping->i_mmap) ||
404 !list_empty(&mapping->i_mmap_nonlinear);
405}
406
407/*
408 * Might pages of this file have been modified in userspace?
409 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
410 * marks vma as VM_SHARED if it is shared, and the file was opened for
411 * writing i.e. vma may be mprotected writable even if now readonly.
412 */
413static inline int mapping_writably_mapped(struct address_space *mapping)
414{
415 return mapping->i_mmap_writable != 0;
416}
417
418/*
419 * Use sequence counter to get consistent i_size on 32-bit processors.
420 */
421#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
422#include <linux/seqlock.h>
423#define __NEED_I_SIZE_ORDERED
424#define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
425#else
426#define i_size_ordered_init(inode) do { } while (0)
427#endif
428
429struct inode {
430 struct hlist_node i_hash;
431 struct list_head i_list;
432 struct list_head i_sb_list;
433 struct list_head i_dentry;
434 unsigned long i_ino;
435 atomic_t i_count;
436 umode_t i_mode;
437 unsigned int i_nlink;
438 uid_t i_uid;
439 gid_t i_gid;
440 dev_t i_rdev;
441 loff_t i_size;
442 struct timespec i_atime;
443 struct timespec i_mtime;
444 struct timespec i_ctime;
445 unsigned int i_blkbits;
446 unsigned long i_blksize;
447 unsigned long i_version;
448 unsigned long i_blocks;
449 unsigned short i_bytes;
450 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
451 struct semaphore i_sem;
452 struct rw_semaphore i_alloc_sem;
453 struct inode_operations *i_op;
454 struct file_operations *i_fop; /* former ->i_op->default_file_ops */
455 struct super_block *i_sb;
456 struct file_lock *i_flock;
457 struct address_space *i_mapping;
458 struct address_space i_data;
459#ifdef CONFIG_QUOTA
460 struct dquot *i_dquot[MAXQUOTAS];
461#endif
462 /* These three should probably be a union */
463 struct list_head i_devices;
464 struct pipe_inode_info *i_pipe;
465 struct block_device *i_bdev;
466 struct cdev *i_cdev;
467 int i_cindex;
468
469 __u32 i_generation;
470
471#ifdef CONFIG_DNOTIFY
472 unsigned long i_dnotify_mask; /* Directory notify events */
473 struct dnotify_struct *i_dnotify; /* for directory notifications */
474#endif
475
476 unsigned long i_state;
477 unsigned long dirtied_when; /* jiffies of first dirtying */
478
479 unsigned int i_flags;
480
481 atomic_t i_writecount;
482 void *i_security;
483 union {
484 void *generic_ip;
485 } u;
486#ifdef __NEED_I_SIZE_ORDERED
487 seqcount_t i_size_seqcount;
488#endif
489};
490
491/*
492 * NOTE: in a 32bit arch with a preemptable kernel and
493 * an UP compile the i_size_read/write must be atomic
494 * with respect to the local cpu (unlike with preempt disabled),
495 * but they don't need to be atomic with respect to other cpus like in
496 * true SMP (so they need either to either locally disable irq around
497 * the read or for example on x86 they can be still implemented as a
498 * cmpxchg8b without the need of the lock prefix). For SMP compiles
499 * and 64bit archs it makes no difference if preempt is enabled or not.
500 */
501static inline loff_t i_size_read(struct inode *inode)
502{
503#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
504 loff_t i_size;
505 unsigned int seq;
506
507 do {
508 seq = read_seqcount_begin(&inode->i_size_seqcount);
509 i_size = inode->i_size;
510 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
511 return i_size;
512#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
513 loff_t i_size;
514
515 preempt_disable();
516 i_size = inode->i_size;
517 preempt_enable();
518 return i_size;
519#else
520 return inode->i_size;
521#endif
522}
523
524
525static inline void i_size_write(struct inode *inode, loff_t i_size)
526{
527#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
528 write_seqcount_begin(&inode->i_size_seqcount);
529 inode->i_size = i_size;
530 write_seqcount_end(&inode->i_size_seqcount);
531#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
532 preempt_disable();
533 inode->i_size = i_size;
534 preempt_enable();
535#else
536 inode->i_size = i_size;
537#endif
538}
539
540static inline unsigned iminor(struct inode *inode)
541{
542 return MINOR(inode->i_rdev);
543}
544
545static inline unsigned imajor(struct inode *inode)
546{
547 return MAJOR(inode->i_rdev);
548}
549
550extern struct block_device *I_BDEV(struct inode *inode);
551
552struct fown_struct {
553 rwlock_t lock; /* protects pid, uid, euid fields */
554 int pid; /* pid or -pgrp where SIGIO should be sent */
555 uid_t uid, euid; /* uid/euid of process setting the owner */
556 void *security;
557 int signum; /* posix.1b rt signal to be delivered on IO */
558};
559
560/*
561 * Track a single file's readahead state
562 */
563struct file_ra_state {
564 unsigned long start; /* Current window */
565 unsigned long size;
566 unsigned long flags; /* ra flags RA_FLAG_xxx*/
567 unsigned long cache_hit; /* cache hit count*/
568 unsigned long prev_page; /* Cache last read() position */
569 unsigned long ahead_start; /* Ahead window */
570 unsigned long ahead_size;
571 unsigned long ra_pages; /* Maximum readahead window */
572 unsigned long mmap_hit; /* Cache hit stat for mmap accesses */
573 unsigned long mmap_miss; /* Cache miss stat for mmap accesses */
574};
575#define RA_FLAG_MISS 0x01 /* a cache miss occured against this file */
576#define RA_FLAG_INCACHE 0x02 /* file is already in cache */
577
578struct file {
579 struct list_head f_list;
580 struct dentry *f_dentry;
581 struct vfsmount *f_vfsmnt;
582 struct file_operations *f_op;
583 atomic_t f_count;
584 unsigned int f_flags;
585 mode_t f_mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 loff_t f_pos;
587 struct fown_struct f_owner;
588 unsigned int f_uid, f_gid;
589 struct file_ra_state f_ra;
590
591 size_t f_maxcount;
592 unsigned long f_version;
593 void *f_security;
594
595 /* needed for tty driver, and maybe others */
596 void *private_data;
597
598#ifdef CONFIG_EPOLL
599 /* Used by fs/eventpoll.c to link all the hooks to this file */
600 struct list_head f_ep_links;
601 spinlock_t f_ep_lock;
602#endif /* #ifdef CONFIG_EPOLL */
603 struct address_space *f_mapping;
604};
605extern spinlock_t files_lock;
606#define file_list_lock() spin_lock(&files_lock);
607#define file_list_unlock() spin_unlock(&files_lock);
608
609#define get_file(x) atomic_inc(&(x)->f_count)
610#define file_count(x) atomic_read(&(x)->f_count)
611
612#define MAX_NON_LFS ((1UL<<31) - 1)
613
614/* Page cache limit. The filesystems should put that into their s_maxbytes
615 limits, otherwise bad things can happen in VM. */
616#if BITS_PER_LONG==32
617#define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
618#elif BITS_PER_LONG==64
619#define MAX_LFS_FILESIZE 0x7fffffffffffffffUL
620#endif
621
622#define FL_POSIX 1
623#define FL_FLOCK 2
624#define FL_ACCESS 8 /* not trying to lock, just looking */
625#define FL_LOCKD 16 /* lock held by rpc.lockd */
626#define FL_LEASE 32 /* lease held on this file */
627#define FL_SLEEP 128 /* A blocking lock */
628
629/*
630 * The POSIX file lock owner is determined by
631 * the "struct files_struct" in the thread group
632 * (or NULL for no owner - BSD locks).
633 *
634 * Lockd stuffs a "host" pointer into this.
635 */
636typedef struct files_struct *fl_owner_t;
637
638struct file_lock_operations {
639 void (*fl_insert)(struct file_lock *); /* lock insertion callback */
640 void (*fl_remove)(struct file_lock *); /* lock removal callback */
641 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
642 void (*fl_release_private)(struct file_lock *);
643};
644
645struct lock_manager_operations {
646 int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
647 void (*fl_notify)(struct file_lock *); /* unblock callback */
648 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
649 void (*fl_release_private)(struct file_lock *);
650 void (*fl_break)(struct file_lock *);
651 int (*fl_mylease)(struct file_lock *, struct file_lock *);
652 int (*fl_change)(struct file_lock **, int);
653};
654
655/* that will die - we need it for nfs_lock_info */
656#include <linux/nfs_fs_i.h>
657
658struct file_lock {
659 struct file_lock *fl_next; /* singly linked list for this inode */
660 struct list_head fl_link; /* doubly linked list of all locks */
661 struct list_head fl_block; /* circular list of blocked processes */
662 fl_owner_t fl_owner;
663 unsigned int fl_pid;
664 wait_queue_head_t fl_wait;
665 struct file *fl_file;
666 unsigned char fl_flags;
667 unsigned char fl_type;
668 loff_t fl_start;
669 loff_t fl_end;
670
671 struct fasync_struct * fl_fasync; /* for lease break notifications */
672 unsigned long fl_break_time; /* for nonblocking lease breaks */
673
674 struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
675 struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
676 union {
677 struct nfs_lock_info nfs_fl;
Trond Myklebust8d0a8a92005-06-22 17:16:32 +0000678 struct nfs4_lock_info nfs4_fl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679 } fl_u;
680};
681
682/* The following constant reflects the upper bound of the file/locking space */
683#ifndef OFFSET_MAX
684#define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
685#define OFFSET_MAX INT_LIMIT(loff_t)
686#define OFFT_OFFSET_MAX INT_LIMIT(off_t)
687#endif
688
689extern struct list_head file_lock_list;
690
691#include <linux/fcntl.h>
692
693extern int fcntl_getlk(struct file *, struct flock __user *);
694extern int fcntl_setlk(struct file *, unsigned int, struct flock __user *);
695
696#if BITS_PER_LONG == 32
697extern int fcntl_getlk64(struct file *, struct flock64 __user *);
698extern int fcntl_setlk64(struct file *, unsigned int, struct flock64 __user *);
699#endif
700
701extern void send_sigio(struct fown_struct *fown, int fd, int band);
702extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
703extern int fcntl_getlease(struct file *filp);
704
705/* fs/locks.c */
706extern void locks_init_lock(struct file_lock *);
707extern void locks_copy_lock(struct file_lock *, struct file_lock *);
708extern void locks_remove_posix(struct file *, fl_owner_t);
709extern void locks_remove_flock(struct file *);
710extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
711extern int posix_lock_file(struct file *, struct file_lock *);
712extern int posix_lock_file_wait(struct file *, struct file_lock *);
713extern void posix_block_lock(struct file_lock *, struct file_lock *);
714extern void posix_unblock_lock(struct file *, struct file_lock *);
715extern int posix_locks_deadlock(struct file_lock *, struct file_lock *);
716extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
717extern int __break_lease(struct inode *inode, unsigned int flags);
718extern void lease_get_mtime(struct inode *, struct timespec *time);
719extern int setlease(struct file *, long, struct file_lock **);
720extern int lease_modify(struct file_lock **, int);
721extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
722extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
723extern void steal_locks(fl_owner_t from);
724
725struct fasync_struct {
726 int magic;
727 int fa_fd;
728 struct fasync_struct *fa_next; /* singly linked list */
729 struct file *fa_file;
730};
731
732#define FASYNC_MAGIC 0x4601
733
734/* SMP safe fasync helpers: */
735extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
736/* can be called from interrupts */
737extern void kill_fasync(struct fasync_struct **, int, int);
738/* only for net: no internal synchronization */
739extern void __kill_fasync(struct fasync_struct *, int, int);
740
741extern int f_setown(struct file *filp, unsigned long arg, int force);
742extern void f_delown(struct file *filp);
743extern int send_sigurg(struct fown_struct *fown);
744
745/*
746 * Umount options
747 */
748
749#define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
750#define MNT_DETACH 0x00000002 /* Just detach from the tree */
751#define MNT_EXPIRE 0x00000004 /* Mark for expiry */
752
753extern struct list_head super_blocks;
754extern spinlock_t sb_lock;
755
756#define sb_entry(list) list_entry((list), struct super_block, s_list)
757#define S_BIAS (1<<30)
758struct super_block {
759 struct list_head s_list; /* Keep this first */
760 dev_t s_dev; /* search index; _not_ kdev_t */
761 unsigned long s_blocksize;
762 unsigned long s_old_blocksize;
763 unsigned char s_blocksize_bits;
764 unsigned char s_dirt;
765 unsigned long long s_maxbytes; /* Max file size */
766 struct file_system_type *s_type;
767 struct super_operations *s_op;
768 struct dquot_operations *dq_op;
769 struct quotactl_ops *s_qcop;
770 struct export_operations *s_export_op;
771 unsigned long s_flags;
772 unsigned long s_magic;
773 struct dentry *s_root;
774 struct rw_semaphore s_umount;
775 struct semaphore s_lock;
776 int s_count;
777 int s_syncing;
778 int s_need_sync_fs;
779 atomic_t s_active;
780 void *s_security;
781 struct xattr_handler **s_xattr;
782
783 struct list_head s_inodes; /* all inodes */
784 struct list_head s_dirty; /* dirty inodes */
785 struct list_head s_io; /* parked for writeback */
786 struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */
787 struct list_head s_files;
788
789 struct block_device *s_bdev;
790 struct list_head s_instances;
791 struct quota_info s_dquot; /* Diskquota specific options */
792
793 int s_frozen;
794 wait_queue_head_t s_wait_unfrozen;
795
796 char s_id[32]; /* Informational name */
797
798 void *s_fs_info; /* Filesystem private info */
799
800 /*
801 * The next field is for VFS *only*. No filesystems have any business
802 * even looking at it. You had been warned.
803 */
804 struct semaphore s_vfs_rename_sem; /* Kludge */
805
806 /* Granuality of c/m/atime in ns.
807 Cannot be worse than a second */
808 u32 s_time_gran;
809};
810
811extern struct timespec current_fs_time(struct super_block *sb);
812
813/*
814 * Snapshotting support.
815 */
816enum {
817 SB_UNFROZEN = 0,
818 SB_FREEZE_WRITE = 1,
819 SB_FREEZE_TRANS = 2,
820};
821
822#define vfs_check_frozen(sb, level) \
823 wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level)))
824
825/*
826 * Superblock locking.
827 */
828static inline void lock_super(struct super_block * sb)
829{
830 down(&sb->s_lock);
831}
832
833static inline void unlock_super(struct super_block * sb)
834{
835 up(&sb->s_lock);
836}
837
838/*
839 * VFS helper functions..
840 */
841extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
842extern int vfs_mkdir(struct inode *, struct dentry *, int);
843extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
844extern int vfs_symlink(struct inode *, struct dentry *, const char *, int);
845extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
846extern int vfs_rmdir(struct inode *, struct dentry *);
847extern int vfs_unlink(struct inode *, struct dentry *);
848extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
849
850/*
851 * VFS dentry helper functions.
852 */
853extern void dentry_unhash(struct dentry *dentry);
854
855/*
856 * File types
857 *
858 * NOTE! These match bits 12..15 of stat.st_mode
859 * (ie "(i_mode >> 12) & 15").
860 */
861#define DT_UNKNOWN 0
862#define DT_FIFO 1
863#define DT_CHR 2
864#define DT_DIR 4
865#define DT_BLK 6
866#define DT_REG 8
867#define DT_LNK 10
868#define DT_SOCK 12
869#define DT_WHT 14
870
871#define OSYNC_METADATA (1<<0)
872#define OSYNC_DATA (1<<1)
873#define OSYNC_INODE (1<<2)
874int generic_osync_inode(struct inode *, struct address_space *, int);
875
876/*
877 * This is the "filldir" function type, used by readdir() to let
878 * the kernel specify what kind of dirent layout it wants to have.
879 * This allows the kernel to read directories into kernel space or
880 * to have different dirent layouts depending on the binary type.
881 */
882typedef int (*filldir_t)(void *, const char *, int, loff_t, ino_t, unsigned);
883
884struct block_device_operations {
885 int (*open) (struct inode *, struct file *);
886 int (*release) (struct inode *, struct file *);
887 int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
Arnd Bergmannbb93e3a2005-06-23 00:10:15 -0700888 long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 long (*compat_ioctl) (struct file *, unsigned, unsigned long);
Carsten Otte420edbc2005-06-23 22:05:23 -0700890 int (*direct_access) (struct block_device *, sector_t, unsigned long *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891 int (*media_changed) (struct gendisk *);
892 int (*revalidate_disk) (struct gendisk *);
893 struct module *owner;
894};
895
896/*
897 * "descriptor" for what we're up to with a read for sendfile().
898 * This allows us to use the same read code yet
899 * have multiple different users of the data that
900 * we read from a file.
901 *
902 * The simplest case just copies the data to user
903 * mode.
904 */
905typedef struct {
906 size_t written;
907 size_t count;
908 union {
909 char __user * buf;
910 void *data;
911 } arg;
912 int error;
913} read_descriptor_t;
914
915typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long);
916
917/* These macros are for out of kernel modules to test that
918 * the kernel supports the unlocked_ioctl and compat_ioctl
919 * fields in struct file_operations. */
920#define HAVE_COMPAT_IOCTL 1
921#define HAVE_UNLOCKED_IOCTL 1
922
923/*
924 * NOTE:
925 * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl
926 * can be called without the big kernel lock held in all filesystems.
927 */
928struct file_operations {
929 struct module *owner;
930 loff_t (*llseek) (struct file *, loff_t, int);
931 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
932 ssize_t (*aio_read) (struct kiocb *, char __user *, size_t, loff_t);
933 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
934 ssize_t (*aio_write) (struct kiocb *, const char __user *, size_t, loff_t);
935 int (*readdir) (struct file *, void *, filldir_t);
936 unsigned int (*poll) (struct file *, struct poll_table_struct *);
937 int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
938 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
939 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
940 int (*mmap) (struct file *, struct vm_area_struct *);
941 int (*open) (struct inode *, struct file *);
942 int (*flush) (struct file *);
943 int (*release) (struct inode *, struct file *);
944 int (*fsync) (struct file *, struct dentry *, int datasync);
945 int (*aio_fsync) (struct kiocb *, int datasync);
946 int (*fasync) (int, struct file *, int);
947 int (*lock) (struct file *, int, struct file_lock *);
948 ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *);
949 ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *);
950 ssize_t (*sendfile) (struct file *, loff_t *, size_t, read_actor_t, void *);
951 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
952 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
953 int (*check_flags)(int);
954 int (*dir_notify)(struct file *filp, unsigned long arg);
955 int (*flock) (struct file *, int, struct file_lock *);
956};
957
958struct inode_operations {
959 int (*create) (struct inode *,struct dentry *,int, struct nameidata *);
960 struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
961 int (*link) (struct dentry *,struct inode *,struct dentry *);
962 int (*unlink) (struct inode *,struct dentry *);
963 int (*symlink) (struct inode *,struct dentry *,const char *);
964 int (*mkdir) (struct inode *,struct dentry *,int);
965 int (*rmdir) (struct inode *,struct dentry *);
966 int (*mknod) (struct inode *,struct dentry *,int,dev_t);
967 int (*rename) (struct inode *, struct dentry *,
968 struct inode *, struct dentry *);
969 int (*readlink) (struct dentry *, char __user *,int);
970 int (*follow_link) (struct dentry *, struct nameidata *);
971 void (*put_link) (struct dentry *, struct nameidata *);
972 void (*truncate) (struct inode *);
973 int (*permission) (struct inode *, int, struct nameidata *);
974 int (*setattr) (struct dentry *, struct iattr *);
975 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
976 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
977 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
978 ssize_t (*listxattr) (struct dentry *, char *, size_t);
979 int (*removexattr) (struct dentry *, const char *);
980};
981
982struct seq_file;
983
984extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
985extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
986extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
987 unsigned long, loff_t *);
988extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
989 unsigned long, loff_t *);
990
991/*
992 * NOTE: write_inode, delete_inode, clear_inode, put_inode can be called
993 * without the big kernel lock held in all filesystems.
994 */
995struct super_operations {
996 struct inode *(*alloc_inode)(struct super_block *sb);
997 void (*destroy_inode)(struct inode *);
998
999 void (*read_inode) (struct inode *);
1000
1001 void (*dirty_inode) (struct inode *);
1002 int (*write_inode) (struct inode *, int);
1003 void (*put_inode) (struct inode *);
1004 void (*drop_inode) (struct inode *);
1005 void (*delete_inode) (struct inode *);
1006 void (*put_super) (struct super_block *);
1007 void (*write_super) (struct super_block *);
1008 int (*sync_fs)(struct super_block *sb, int wait);
1009 void (*write_super_lockfs) (struct super_block *);
1010 void (*unlockfs) (struct super_block *);
1011 int (*statfs) (struct super_block *, struct kstatfs *);
1012 int (*remount_fs) (struct super_block *, int *, char *);
1013 void (*clear_inode) (struct inode *);
1014 void (*umount_begin) (struct super_block *);
1015
1016 int (*show_options)(struct seq_file *, struct vfsmount *);
1017
1018 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1019 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1020};
1021
1022/* Inode state bits. Protected by inode_lock. */
1023#define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */
1024#define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */
1025#define I_DIRTY_PAGES 4 /* Data-related inode changes pending */
1026#define __I_LOCK 3
1027#define I_LOCK (1 << __I_LOCK)
1028#define I_FREEING 16
1029#define I_CLEAR 32
1030#define I_NEW 64
Alexander Viro991114c2005-06-23 00:09:01 -07001031#define I_WILL_FREE 128
Linus Torvalds1da177e2005-04-16 15:20:36 -07001032
1033#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1034
1035extern void __mark_inode_dirty(struct inode *, int);
1036static inline void mark_inode_dirty(struct inode *inode)
1037{
1038 __mark_inode_dirty(inode, I_DIRTY);
1039}
1040
1041static inline void mark_inode_dirty_sync(struct inode *inode)
1042{
1043 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1044}
1045
1046static inline void touch_atime(struct vfsmount *mnt, struct dentry *dentry)
1047{
1048 /* per-mountpoint checks will go here */
1049 update_atime(dentry->d_inode);
1050}
1051
1052static inline void file_accessed(struct file *file)
1053{
1054 if (!(file->f_flags & O_NOATIME))
1055 touch_atime(file->f_vfsmnt, file->f_dentry);
1056}
1057
1058int sync_inode(struct inode *inode, struct writeback_control *wbc);
1059
1060/**
Pavel Pisa4dc3b162005-05-01 08:59:25 -07001061 * struct export_operations - for nfsd to communicate with file systems
1062 * @decode_fh: decode a file handle fragment and return a &struct dentry
1063 * @encode_fh: encode a file handle fragment from a dentry
1064 * @get_name: find the name for a given inode in a given directory
1065 * @get_parent: find the parent of a given directory
1066 * @get_dentry: find a dentry for the inode given a file handle sub-fragment
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 *
1068 * Description:
1069 * The export_operations structure provides a means for nfsd to communicate
1070 * with a particular exported file system - particularly enabling nfsd and
1071 * the filesystem to co-operate when dealing with file handles.
1072 *
Martin Waitz67be2dd2005-05-01 08:59:26 -07001073 * export_operations contains two basic operation for dealing with file
1074 * handles, decode_fh() and encode_fh(), and allows for some other
1075 * operations to be defined which standard helper routines use to get
1076 * specific information from the filesystem.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077 *
1078 * nfsd encodes information use to determine which filesystem a filehandle
Martin Waitz67be2dd2005-05-01 08:59:26 -07001079 * applies to in the initial part of the file handle. The remainder, termed
1080 * a file handle fragment, is controlled completely by the filesystem. The
1081 * standard helper routines assume that this fragment will contain one or
1082 * two sub-fragments, one which identifies the file, and one which may be
1083 * used to identify the (a) directory containing the file.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084 *
1085 * In some situations, nfsd needs to get a dentry which is connected into a
Martin Waitz67be2dd2005-05-01 08:59:26 -07001086 * specific part of the file tree. To allow for this, it passes the
1087 * function acceptable() together with a @context which can be used to see
1088 * if the dentry is acceptable. As there can be multiple dentrys for a
1089 * given file, the filesystem should check each one for acceptability before
1090 * looking for the next. As soon as an acceptable one is found, it should
1091 * be returned.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092 *
1093 * decode_fh:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001094 * @decode_fh is given a &struct super_block (@sb), a file handle fragment
1095 * (@fh, @fh_len) and an acceptability testing function (@acceptable,
1096 * @context). It should return a &struct dentry which refers to the same
1097 * file that the file handle fragment refers to, and which passes the
1098 * acceptability test. If it cannot, it should return a %NULL pointer if
1099 * the file was found but no acceptable &dentries were available, or a
1100 * %ERR_PTR error code indicating why it couldn't be found (e.g. %ENOENT or
1101 * %ENOMEM).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102 *
1103 * encode_fh:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001104 * @encode_fh should store in the file handle fragment @fh (using at most
1105 * @max_len bytes) information that can be used by @decode_fh to recover the
1106 * file refered to by the &struct dentry @de. If the @connectable flag is
1107 * set, the encode_fh() should store sufficient information so that a good
1108 * attempt can be made to find not only the file but also it's place in the
1109 * filesystem. This typically means storing a reference to de->d_parent in
1110 * the filehandle fragment. encode_fh() should return the number of bytes
1111 * stored or a negative error code such as %-ENOSPC
Linus Torvalds1da177e2005-04-16 15:20:36 -07001112 *
1113 * get_name:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001114 * @get_name should find a name for the given @child in the given @parent
1115 * directory. The name should be stored in the @name (with the
1116 * understanding that it is already pointing to a a %NAME_MAX+1 sized
1117 * buffer. get_name() should return %0 on success, a negative error code
1118 * or error. @get_name will be called without @parent->i_sem held.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119 *
1120 * get_parent:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001121 * @get_parent should find the parent directory for the given @child which
1122 * is also a directory. In the event that it cannot be found, or storage
1123 * space cannot be allocated, a %ERR_PTR should be returned.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001124 *
1125 * get_dentry:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001126 * Given a &super_block (@sb) and a pointer to a file-system specific inode
1127 * identifier, possibly an inode number, (@inump) get_dentry() should find
1128 * the identified inode and return a dentry for that inode. Any suitable
1129 * dentry can be returned including, if necessary, a new dentry created with
1130 * d_alloc_root. The caller can then find any other extant dentrys by
1131 * following the d_alias links. If a new dentry was created using
1132 * d_alloc_root, DCACHE_NFSD_DISCONNECTED should be set, and the dentry
1133 * should be d_rehash()ed.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134 *
Martin Waitz67be2dd2005-05-01 08:59:26 -07001135 * If the inode cannot be found, either a %NULL pointer or an %ERR_PTR code
1136 * can be returned. The @inump will be whatever was passed to
1137 * nfsd_find_fh_dentry() in either the @obj or @parent parameters.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138 *
1139 * Locking rules:
Martin Waitz67be2dd2005-05-01 08:59:26 -07001140 * get_parent is called with child->d_inode->i_sem down
1141 * get_name is not (which is possibly inconsistent)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001142 */
1143
1144struct export_operations {
1145 struct dentry *(*decode_fh)(struct super_block *sb, __u32 *fh, int fh_len, int fh_type,
1146 int (*acceptable)(void *context, struct dentry *de),
1147 void *context);
1148 int (*encode_fh)(struct dentry *de, __u32 *fh, int *max_len,
1149 int connectable);
1150
1151 /* the following are only called from the filesystem itself */
1152 int (*get_name)(struct dentry *parent, char *name,
1153 struct dentry *child);
1154 struct dentry * (*get_parent)(struct dentry *child);
1155 struct dentry * (*get_dentry)(struct super_block *sb, void *inump);
1156
1157 /* This is set by the exporting module to a standard helper */
1158 struct dentry * (*find_exported_dentry)(
1159 struct super_block *sb, void *obj, void *parent,
1160 int (*acceptable)(void *context, struct dentry *de),
1161 void *context);
1162
1163
1164};
1165
1166extern struct dentry *
1167find_exported_dentry(struct super_block *sb, void *obj, void *parent,
1168 int (*acceptable)(void *context, struct dentry *de),
1169 void *context);
1170
1171struct file_system_type {
1172 const char *name;
1173 int fs_flags;
1174 struct super_block *(*get_sb) (struct file_system_type *, int,
1175 const char *, void *);
1176 void (*kill_sb) (struct super_block *);
1177 struct module *owner;
1178 struct file_system_type * next;
1179 struct list_head fs_supers;
1180};
1181
1182struct super_block *get_sb_bdev(struct file_system_type *fs_type,
1183 int flags, const char *dev_name, void *data,
1184 int (*fill_super)(struct super_block *, void *, int));
1185struct super_block *get_sb_single(struct file_system_type *fs_type,
1186 int flags, void *data,
1187 int (*fill_super)(struct super_block *, void *, int));
1188struct super_block *get_sb_nodev(struct file_system_type *fs_type,
1189 int flags, void *data,
1190 int (*fill_super)(struct super_block *, void *, int));
1191void generic_shutdown_super(struct super_block *sb);
1192void kill_block_super(struct super_block *sb);
1193void kill_anon_super(struct super_block *sb);
1194void kill_litter_super(struct super_block *sb);
1195void deactivate_super(struct super_block *sb);
1196int set_anon_super(struct super_block *s, void *data);
1197struct super_block *sget(struct file_system_type *type,
1198 int (*test)(struct super_block *,void *),
1199 int (*set)(struct super_block *,void *),
1200 void *data);
1201struct super_block *get_sb_pseudo(struct file_system_type *, char *,
1202 struct super_operations *ops, unsigned long);
1203int __put_super(struct super_block *sb);
1204int __put_super_and_need_restart(struct super_block *sb);
1205void unnamed_dev_init(void);
1206
1207/* Alas, no aliases. Too much hassle with bringing module.h everywhere */
1208#define fops_get(fops) \
1209 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
1210#define fops_put(fops) \
1211 do { if (fops) module_put((fops)->owner); } while(0)
1212
1213extern int register_filesystem(struct file_system_type *);
1214extern int unregister_filesystem(struct file_system_type *);
1215extern struct vfsmount *kern_mount(struct file_system_type *);
1216extern int may_umount_tree(struct vfsmount *);
1217extern int may_umount(struct vfsmount *);
1218extern long do_mount(char *, char *, char *, unsigned long, void *);
1219
1220extern int vfs_statfs(struct super_block *, struct kstatfs *);
1221
1222#define FLOCK_VERIFY_READ 1
1223#define FLOCK_VERIFY_WRITE 2
1224
1225extern int locks_mandatory_locked(struct inode *);
1226extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
1227
1228/*
1229 * Candidates for mandatory locking have the setgid bit set
1230 * but no group execute bit - an otherwise meaningless combination.
1231 */
1232#define MANDATORY_LOCK(inode) \
1233 (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
1234
1235static inline int locks_verify_locked(struct inode *inode)
1236{
1237 if (MANDATORY_LOCK(inode))
1238 return locks_mandatory_locked(inode);
1239 return 0;
1240}
1241
1242extern int rw_verify_area(int, struct file *, loff_t *, size_t);
1243
1244static inline int locks_verify_truncate(struct inode *inode,
1245 struct file *filp,
1246 loff_t size)
1247{
1248 if (inode->i_flock && MANDATORY_LOCK(inode))
1249 return locks_mandatory_area(
1250 FLOCK_VERIFY_WRITE, inode, filp,
1251 size < inode->i_size ? size : inode->i_size,
1252 (size < inode->i_size ? inode->i_size - size
1253 : size - inode->i_size)
1254 );
1255 return 0;
1256}
1257
1258static inline int break_lease(struct inode *inode, unsigned int mode)
1259{
1260 if (inode->i_flock)
1261 return __break_lease(inode, mode);
1262 return 0;
1263}
1264
1265/* fs/open.c */
1266
1267extern int do_truncate(struct dentry *, loff_t start);
1268extern struct file *filp_open(const char *, int, int);
1269extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
1270extern int filp_close(struct file *, fl_owner_t id);
1271extern char * getname(const char __user *);
1272
1273/* fs/dcache.c */
1274extern void __init vfs_caches_init_early(void);
1275extern void __init vfs_caches_init(unsigned long);
1276
1277#define __getname() kmem_cache_alloc(names_cachep, SLAB_KERNEL)
1278#define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
1279#ifndef CONFIG_AUDITSYSCALL
1280#define putname(name) __putname(name)
1281#else
1282extern void putname(const char *name);
1283#endif
1284
1285extern int register_blkdev(unsigned int, const char *);
1286extern int unregister_blkdev(unsigned int, const char *);
1287extern struct block_device *bdget(dev_t);
1288extern void bd_set_size(struct block_device *, loff_t size);
1289extern void bd_forget(struct inode *inode);
1290extern void bdput(struct block_device *);
1291extern struct block_device *open_by_devnum(dev_t, unsigned);
1292extern struct file_operations def_blk_fops;
1293extern struct address_space_operations def_blk_aops;
1294extern struct file_operations def_chr_fops;
1295extern struct file_operations bad_sock_fops;
1296extern struct file_operations def_fifo_fops;
1297extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
1298extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
1299extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
1300extern int blkdev_get(struct block_device *, mode_t, unsigned);
1301extern int blkdev_put(struct block_device *);
1302extern int bd_claim(struct block_device *, void *);
1303extern void bd_release(struct block_device *);
1304
1305/* fs/char_dev.c */
1306extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
1307extern int register_chrdev_region(dev_t, unsigned, const char *);
1308extern int register_chrdev(unsigned int, const char *,
1309 struct file_operations *);
1310extern int unregister_chrdev(unsigned int, const char *);
1311extern void unregister_chrdev_region(dev_t, unsigned);
1312extern int chrdev_open(struct inode *, struct file *);
1313
1314/* fs/block_dev.c */
1315#define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
1316extern const char *__bdevname(dev_t, char *buffer);
1317extern const char *bdevname(struct block_device *bdev, char *buffer);
1318extern struct block_device *lookup_bdev(const char *);
1319extern struct block_device *open_bdev_excl(const char *, int, void *);
1320extern void close_bdev_excl(struct block_device *);
1321
1322extern void init_special_inode(struct inode *, umode_t, dev_t);
1323
1324/* Invalid inode operations -- fs/bad_inode.c */
1325extern void make_bad_inode(struct inode *);
1326extern int is_bad_inode(struct inode *);
1327
1328extern struct file_operations read_fifo_fops;
1329extern struct file_operations write_fifo_fops;
1330extern struct file_operations rdwr_fifo_fops;
1331extern struct file_operations read_pipe_fops;
1332extern struct file_operations write_pipe_fops;
1333extern struct file_operations rdwr_pipe_fops;
1334
1335extern int fs_may_remount_ro(struct super_block *);
1336
1337/*
1338 * return READ, READA, or WRITE
1339 */
1340#define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
1341
1342/*
1343 * return data direction, READ or WRITE
1344 */
1345#define bio_data_dir(bio) ((bio)->bi_rw & 1)
1346
1347extern int check_disk_change(struct block_device *);
1348extern int invalidate_inodes(struct super_block *);
Christoph Hellwig2ef41632005-05-05 16:15:59 -07001349extern int __invalidate_device(struct block_device *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350extern int invalidate_partition(struct gendisk *, int);
1351unsigned long invalidate_mapping_pages(struct address_space *mapping,
1352 pgoff_t start, pgoff_t end);
1353unsigned long invalidate_inode_pages(struct address_space *mapping);
1354static inline void invalidate_remote_inode(struct inode *inode)
1355{
1356 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1357 S_ISLNK(inode->i_mode))
1358 invalidate_inode_pages(inode->i_mapping);
1359}
1360extern int invalidate_inode_pages2(struct address_space *mapping);
1361extern int invalidate_inode_pages2_range(struct address_space *mapping,
1362 pgoff_t start, pgoff_t end);
1363extern int write_inode_now(struct inode *, int);
1364extern int filemap_fdatawrite(struct address_space *);
1365extern int filemap_flush(struct address_space *);
1366extern int filemap_fdatawait(struct address_space *);
1367extern int filemap_write_and_wait(struct address_space *mapping);
1368extern int filemap_write_and_wait_range(struct address_space *mapping,
1369 loff_t lstart, loff_t lend);
1370extern void sync_supers(void);
1371extern void sync_filesystems(int wait);
1372extern void emergency_sync(void);
1373extern void emergency_remount(void);
1374extern int do_remount_sb(struct super_block *sb, int flags,
1375 void *data, int force);
1376extern sector_t bmap(struct inode *, sector_t);
1377extern int setattr_mask(unsigned int);
1378extern int notify_change(struct dentry *, struct iattr *);
1379extern int permission(struct inode *, int, struct nameidata *);
1380extern int generic_permission(struct inode *, int,
1381 int (*check_acl)(struct inode *, int));
1382
1383extern int get_write_access(struct inode *);
1384extern int deny_write_access(struct file *);
1385static inline void put_write_access(struct inode * inode)
1386{
1387 atomic_dec(&inode->i_writecount);
1388}
1389static inline void allow_write_access(struct file *file)
1390{
1391 if (file)
1392 atomic_inc(&file->f_dentry->d_inode->i_writecount);
1393}
1394extern int do_pipe(int *);
1395
1396extern int open_namei(const char *, int, int, struct nameidata *);
1397extern int may_open(struct nameidata *, int, int);
1398
1399extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
1400extern struct file * open_exec(const char *);
1401
1402/* fs/dcache.c -- generic fs support functions */
1403extern int is_subdir(struct dentry *, struct dentry *);
1404extern ino_t find_inode_number(struct dentry *, struct qstr *);
1405
1406#include <linux/err.h>
1407
1408/* needed for stackable file system support */
1409extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
1410
1411extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
1412
1413extern void inode_init_once(struct inode *);
1414extern void iput(struct inode *);
1415extern struct inode * igrab(struct inode *);
1416extern ino_t iunique(struct super_block *, ino_t);
1417extern int inode_needs_sync(struct inode *inode);
1418extern void generic_delete_inode(struct inode *inode);
1419
1420extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
1421 int (*test)(struct inode *, void *), void *data);
1422extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
1423
1424extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
1425extern struct inode * iget_locked(struct super_block *, unsigned long);
1426extern void unlock_new_inode(struct inode *);
1427
1428static inline struct inode *iget(struct super_block *sb, unsigned long ino)
1429{
1430 struct inode *inode = iget_locked(sb, ino);
1431
1432 if (inode && (inode->i_state & I_NEW)) {
1433 sb->s_op->read_inode(inode);
1434 unlock_new_inode(inode);
1435 }
1436
1437 return inode;
1438}
1439
1440extern void __iget(struct inode * inode);
1441extern void clear_inode(struct inode *);
1442extern void destroy_inode(struct inode *);
1443extern struct inode *new_inode(struct super_block *);
1444extern int remove_suid(struct dentry *);
1445extern void remove_dquot_ref(struct super_block *, int, struct list_head *);
1446extern struct semaphore iprune_sem;
1447
1448extern void __insert_inode_hash(struct inode *, unsigned long hashval);
1449extern void remove_inode_hash(struct inode *);
1450static inline void insert_inode_hash(struct inode *inode) {
1451 __insert_inode_hash(inode, inode->i_ino);
1452}
1453
1454extern struct file * get_empty_filp(void);
1455extern void file_move(struct file *f, struct list_head *list);
1456extern void file_kill(struct file *f);
1457struct bio;
1458extern void submit_bio(int, struct bio *);
1459extern int bdev_read_only(struct block_device *);
1460extern int set_blocksize(struct block_device *, int);
1461extern int sb_set_blocksize(struct super_block *, int);
1462extern int sb_min_blocksize(struct super_block *, int);
1463
1464extern int generic_file_mmap(struct file *, struct vm_area_struct *);
1465extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
1466extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1467extern int file_send_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1468extern ssize_t generic_file_read(struct file *, char __user *, size_t, loff_t *);
1469int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
1470extern ssize_t generic_file_write(struct file *, const char __user *, size_t, loff_t *);
1471extern ssize_t generic_file_aio_read(struct kiocb *, char __user *, size_t, loff_t);
1472extern ssize_t __generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t *);
1473extern ssize_t generic_file_aio_write(struct kiocb *, const char __user *, size_t, loff_t);
1474extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
1475 unsigned long, loff_t *);
1476extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
1477 unsigned long *, loff_t, loff_t *, size_t, size_t);
1478extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
1479 unsigned long, loff_t, loff_t *, size_t, ssize_t);
1480extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
1481extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
1482ssize_t generic_file_write_nolock(struct file *file, const struct iovec *iov,
1483 unsigned long nr_segs, loff_t *ppos);
1484extern ssize_t generic_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
1485extern void do_generic_mapping_read(struct address_space *mapping,
1486 struct file_ra_state *, struct file *,
1487 loff_t *, read_descriptor_t *, read_actor_t);
1488extern void
1489file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
1490extern ssize_t generic_file_direct_IO(int rw, struct kiocb *iocb,
1491 const struct iovec *iov, loff_t offset, unsigned long nr_segs);
1492extern ssize_t generic_file_readv(struct file *filp, const struct iovec *iov,
1493 unsigned long nr_segs, loff_t *ppos);
1494ssize_t generic_file_writev(struct file *filp, const struct iovec *iov,
1495 unsigned long nr_segs, loff_t *ppos);
1496extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
1497extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
1498extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
1499extern int generic_file_open(struct inode * inode, struct file * filp);
1500extern int nonseekable_open(struct inode * inode, struct file * filp);
1501
Carsten Otteceffc072005-06-23 22:05:25 -07001502#ifdef CONFIG_FS_XIP
Carsten Otteeb6fe0c2005-06-23 22:05:28 -07001503extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
1504 loff_t *ppos);
Carsten Otteceffc072005-06-23 22:05:25 -07001505extern ssize_t xip_file_sendfile(struct file *in_file, loff_t *ppos,
1506 size_t count, read_actor_t actor,
1507 void *target);
1508extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
Carsten Otteeb6fe0c2005-06-23 22:05:28 -07001509extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
1510 size_t len, loff_t *ppos);
Carsten Otteceffc072005-06-23 22:05:25 -07001511extern int xip_truncate_page(struct address_space *mapping, loff_t from);
Carsten Otte6d791252005-06-23 22:05:26 -07001512#else
1513static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
1514{
1515 return 0;
1516}
Carsten Otteceffc072005-06-23 22:05:25 -07001517#endif
1518
Linus Torvalds1da177e2005-04-16 15:20:36 -07001519static inline void do_generic_file_read(struct file * filp, loff_t *ppos,
1520 read_descriptor_t * desc,
1521 read_actor_t actor)
1522{
1523 do_generic_mapping_read(filp->f_mapping,
1524 &filp->f_ra,
1525 filp,
1526 ppos,
1527 desc,
1528 actor);
1529}
1530
1531ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
1532 struct block_device *bdev, const struct iovec *iov, loff_t offset,
1533 unsigned long nr_segs, get_blocks_t get_blocks, dio_iodone_t end_io,
1534 int lock_type);
1535
1536enum {
1537 DIO_LOCKING = 1, /* need locking between buffered and direct access */
1538 DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */
1539 DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */
1540};
1541
1542static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
1543 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1544 loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
1545 dio_iodone_t end_io)
1546{
1547 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1548 nr_segs, get_blocks, end_io, DIO_LOCKING);
1549}
1550
1551static inline ssize_t blockdev_direct_IO_no_locking(int rw, struct kiocb *iocb,
1552 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1553 loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
1554 dio_iodone_t end_io)
1555{
1556 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1557 nr_segs, get_blocks, end_io, DIO_NO_LOCKING);
1558}
1559
1560static inline ssize_t blockdev_direct_IO_own_locking(int rw, struct kiocb *iocb,
1561 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1562 loff_t offset, unsigned long nr_segs, get_blocks_t get_blocks,
1563 dio_iodone_t end_io)
1564{
1565 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1566 nr_segs, get_blocks, end_io, DIO_OWN_LOCKING);
1567}
1568
1569extern struct file_operations generic_ro_fops;
1570
1571#define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
1572
1573extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
1574extern int vfs_follow_link(struct nameidata *, const char *);
1575extern int page_readlink(struct dentry *, char __user *, int);
1576extern int page_follow_link_light(struct dentry *, struct nameidata *);
1577extern void page_put_link(struct dentry *, struct nameidata *);
1578extern int page_symlink(struct inode *inode, const char *symname, int len);
1579extern struct inode_operations page_symlink_inode_operations;
1580extern int generic_readlink(struct dentry *, char __user *, int);
1581extern void generic_fillattr(struct inode *, struct kstat *);
1582extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1583void inode_add_bytes(struct inode *inode, loff_t bytes);
1584void inode_sub_bytes(struct inode *inode, loff_t bytes);
1585loff_t inode_get_bytes(struct inode *inode);
1586void inode_set_bytes(struct inode *inode, loff_t bytes);
1587
1588extern int vfs_readdir(struct file *, filldir_t, void *);
1589
1590extern int vfs_stat(char __user *, struct kstat *);
1591extern int vfs_lstat(char __user *, struct kstat *);
1592extern int vfs_fstat(unsigned int, struct kstat *);
1593
1594extern int vfs_ioctl(struct file *, unsigned int, unsigned int, unsigned long);
1595
1596extern struct file_system_type *get_fs_type(const char *name);
1597extern struct super_block *get_super(struct block_device *);
1598extern struct super_block *user_get_super(dev_t);
1599extern void drop_super(struct super_block *sb);
1600
1601extern int dcache_dir_open(struct inode *, struct file *);
1602extern int dcache_dir_close(struct inode *, struct file *);
1603extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
1604extern int dcache_readdir(struct file *, void *, filldir_t);
1605extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1606extern int simple_statfs(struct super_block *, struct kstatfs *);
1607extern int simple_link(struct dentry *, struct inode *, struct dentry *);
1608extern int simple_unlink(struct inode *, struct dentry *);
1609extern int simple_rmdir(struct inode *, struct dentry *);
1610extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1611extern int simple_sync_file(struct file *, struct dentry *, int);
1612extern int simple_empty(struct dentry *);
1613extern int simple_readpage(struct file *file, struct page *page);
1614extern int simple_prepare_write(struct file *file, struct page *page,
1615 unsigned offset, unsigned to);
1616extern int simple_commit_write(struct file *file, struct page *page,
1617 unsigned offset, unsigned to);
1618
1619extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
1620extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
1621extern struct file_operations simple_dir_operations;
1622extern struct inode_operations simple_dir_inode_operations;
1623struct tree_descr { char *name; struct file_operations *ops; int mode; };
1624struct dentry *d_alloc_name(struct dentry *, const char *);
1625extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
1626extern int simple_pin_fs(char *name, struct vfsmount **mount, int *count);
1627extern void simple_release_fs(struct vfsmount **mount, int *count);
1628
1629extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t);
1630
1631extern int inode_change_ok(struct inode *, struct iattr *);
1632extern int __must_check inode_setattr(struct inode *, struct iattr *);
1633
1634extern void inode_update_time(struct inode *inode, int ctime_too);
1635
1636static inline ino_t parent_ino(struct dentry *dentry)
1637{
1638 ino_t res;
1639
1640 spin_lock(&dentry->d_lock);
1641 res = dentry->d_parent->d_inode->i_ino;
1642 spin_unlock(&dentry->d_lock);
1643 return res;
1644}
1645
1646/* kernel/fork.c */
1647extern int unshare_files(void);
1648
1649/* Transaction based IO helpers */
1650
1651/*
1652 * An argresp is stored in an allocated page and holds the
1653 * size of the argument or response, along with its content
1654 */
1655struct simple_transaction_argresp {
1656 ssize_t size;
1657 char data[0];
1658};
1659
1660#define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
1661
1662char *simple_transaction_get(struct file *file, const char __user *buf,
1663 size_t size);
1664ssize_t simple_transaction_read(struct file *file, char __user *buf,
1665 size_t size, loff_t *pos);
1666int simple_transaction_release(struct inode *inode, struct file *file);
1667
1668static inline void simple_transaction_set(struct file *file, size_t n)
1669{
1670 struct simple_transaction_argresp *ar = file->private_data;
1671
1672 BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
1673
1674 /*
1675 * The barrier ensures that ar->size will really remain zero until
1676 * ar->data is ready for reading.
1677 */
1678 smp_mb();
1679 ar->size = n;
1680}
1681
Arnd Bergmannacaefc22005-05-18 14:40:59 +02001682/*
1683 * simple attribute files
1684 *
1685 * These attributes behave similar to those in sysfs:
1686 *
1687 * Writing to an attribute immediately sets a value, an open file can be
1688 * written to multiple times.
1689 *
1690 * Reading from an attribute creates a buffer from the value that might get
1691 * read with multiple read calls. When the attribute has been read
1692 * completely, no further read calls are possible until the file is opened
1693 * again.
1694 *
1695 * All attributes contain a text representation of a numeric value
1696 * that are accessed with the get() and set() functions.
1697 */
1698#define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
1699static int __fops ## _open(struct inode *inode, struct file *file) \
1700{ \
1701 __simple_attr_check_format(__fmt, 0ull); \
1702 return simple_attr_open(inode, file, __get, __set, __fmt); \
1703} \
1704static struct file_operations __fops = { \
1705 .owner = THIS_MODULE, \
1706 .open = __fops ## _open, \
1707 .release = simple_attr_close, \
1708 .read = simple_attr_read, \
1709 .write = simple_attr_write, \
1710};
1711
1712static inline void __attribute__((format(printf, 1, 2)))
1713__simple_attr_check_format(const char *fmt, ...)
1714{
1715 /* don't do anything, just let the compiler check the arguments; */
1716}
1717
1718int simple_attr_open(struct inode *inode, struct file *file,
1719 u64 (*get)(void *), void (*set)(void *, u64),
1720 const char *fmt);
1721int simple_attr_close(struct inode *inode, struct file *file);
1722ssize_t simple_attr_read(struct file *file, char __user *buf,
1723 size_t len, loff_t *ppos);
1724ssize_t simple_attr_write(struct file *file, const char __user *buf,
1725 size_t len, loff_t *ppos);
1726
1727
Linus Torvalds1da177e2005-04-16 15:20:36 -07001728#ifdef CONFIG_SECURITY
1729static inline char *alloc_secdata(void)
1730{
1731 return (char *)get_zeroed_page(GFP_KERNEL);
1732}
1733
1734static inline void free_secdata(void *secdata)
1735{
1736 free_page((unsigned long)secdata);
1737}
1738#else
1739static inline char *alloc_secdata(void)
1740{
1741 return (char *)1;
1742}
1743
1744static inline void free_secdata(void *secdata)
1745{ }
1746#endif /* CONFIG_SECURITY */
1747
1748#endif /* __KERNEL__ */
1749#endif /* _LINUX_FS_H */