net: Fix recursive descent in __scm_destroy().
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / include / linux / fs.h
blob580b513668feffbb32f9d161113e10b17718dfe5
1 #ifndef _LINUX_FS_H
2 #define _LINUX_FS_H
4 /*
5 * This file has definitions for some important file table
6 * structures etc.
7 */
9 #include <linux/limits.h>
10 #include <linux/ioctl.h>
13 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
14 * the file limit at runtime and only root can increase the per-process
15 * nr_file rlimit, so it's safe to set up a ridiculously high absolute
16 * upper limit on files-per-process.
18 * Some programs (notably those using select()) may have to be
19 * recompiled to take full advantage of the new limits..
22 /* Fixed constants first: */
23 #undef NR_OPEN
24 extern int sysctl_nr_open;
25 #define INR_OPEN 1024 /* Initial setting for nfile rlimits */
27 #define BLOCK_SIZE_BITS 10
28 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
30 #define SEEK_SET 0 /* seek relative to beginning of file */
31 #define SEEK_CUR 1 /* seek relative to current file position */
32 #define SEEK_END 2 /* seek relative to end of file */
33 #define SEEK_MAX SEEK_END
35 /* And dynamically-tunable limits and defaults: */
36 struct files_stat_struct {
37 int nr_files; /* read only */
38 int nr_free_files; /* read only */
39 int max_files; /* tunable */
41 extern struct files_stat_struct files_stat;
42 extern int get_max_files(void);
44 struct inodes_stat_t {
45 int nr_inodes;
46 int nr_unused;
47 int dummy[5]; /* padding for sysctl ABI compatibility */
49 extern struct inodes_stat_t inodes_stat;
51 extern int leases_enable, lease_break_time;
53 #ifdef CONFIG_DNOTIFY
54 extern int dir_notify_enable;
55 #endif
57 #define NR_FILE 8192 /* this can well be larger on a larger system */
59 #define MAY_EXEC 1
60 #define MAY_WRITE 2
61 #define MAY_READ 4
62 #define MAY_APPEND 8
63 #define MAY_ACCESS 16
64 #define MAY_OPEN 32
66 #define FMODE_READ 1
67 #define FMODE_WRITE 2
69 /* Internal kernel extensions */
70 #define FMODE_LSEEK 4
71 #define FMODE_PREAD 8
72 #define FMODE_PWRITE FMODE_PREAD /* These go hand in hand */
74 /* File is being opened for execution. Primary users of this flag are
75 distributed filesystems that can use it to achieve correct ETXTBUSY
76 behavior for cross-node execution/opening_for_writing of files */
77 #define FMODE_EXEC 16
79 #define RW_MASK 1
80 #define RWA_MASK 2
81 #define READ 0
82 #define WRITE 1
83 #define READA 2 /* read-ahead - don't block if no resources */
84 #define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */
85 #define READ_SYNC (READ | (1 << BIO_RW_SYNC))
86 #define READ_META (READ | (1 << BIO_RW_META))
87 #define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC))
88 #define SWRITE_SYNC (SWRITE | (1 << BIO_RW_SYNC))
89 #define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
91 #define SEL_IN 1
92 #define SEL_OUT 2
93 #define SEL_EX 4
95 /* public flags for file_system_type */
96 #define FS_REQUIRES_DEV 1
97 #define FS_BINARY_MOUNTDATA 2
98 #define FS_HAS_SUBTYPE 4
99 #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
100 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move()
101 * during rename() internally.
105 * These are the fs-independent mount-flags: up to 32 flags are supported
107 #define MS_RDONLY 1 /* Mount read-only */
108 #define MS_NOSUID 2 /* Ignore suid and sgid bits */
109 #define MS_NODEV 4 /* Disallow access to device special files */
110 #define MS_NOEXEC 8 /* Disallow program execution */
111 #define MS_SYNCHRONOUS 16 /* Writes are synced at once */
112 #define MS_REMOUNT 32 /* Alter flags of a mounted FS */
113 #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
114 #define MS_DIRSYNC 128 /* Directory modifications are synchronous */
115 #define MS_NOATIME 1024 /* Do not update access times. */
116 #define MS_NODIRATIME 2048 /* Do not update directory access times */
117 #define MS_BIND 4096
118 #define MS_MOVE 8192
119 #define MS_REC 16384
120 #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence.
121 MS_VERBOSE is deprecated. */
122 #define MS_SILENT 32768
123 #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
124 #define MS_UNBINDABLE (1<<17) /* change to unbindable */
125 #define MS_PRIVATE (1<<18) /* change to private */
126 #define MS_SLAVE (1<<19) /* change to slave */
127 #define MS_SHARED (1<<20) /* change to shared */
128 #define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */
129 #define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */
130 #define MS_I_VERSION (1<<23) /* Update inode I_version field */
131 #define MS_ACTIVE (1<<30)
132 #define MS_NOUSER (1<<31)
135 * Superblock flags that can be altered by MS_REMOUNT
137 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK)
140 * Old magic mount flag and mask
142 #define MS_MGC_VAL 0xC0ED0000
143 #define MS_MGC_MSK 0xffff0000
145 /* Inode flags - they have nothing to superblock flags now */
147 #define S_SYNC 1 /* Writes are synced at once */
148 #define S_NOATIME 2 /* Do not update access times */
149 #define S_APPEND 4 /* Append-only file */
150 #define S_IMMUTABLE 8 /* Immutable file */
151 #define S_DEAD 16 /* removed, but still open directory */
152 #define S_NOQUOTA 32 /* Inode is not counted to quota */
153 #define S_DIRSYNC 64 /* Directory modifications are synchronous */
154 #define S_NOCMTIME 128 /* Do not update file c/mtime */
155 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
156 #define S_PRIVATE 512 /* Inode is fs-internal */
159 * Note that nosuid etc flags are inode-specific: setting some file-system
160 * flags just means all the inodes inherit those flags by default. It might be
161 * possible to override it selectively if you really wanted to with some
162 * ioctl() that is not currently implemented.
164 * Exception: MS_RDONLY is always applied to the entire file system.
166 * Unfortunately, it is possible to change a filesystems flags with it mounted
167 * with files in use. This means that all of the inodes will not have their
168 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
169 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
171 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
173 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
174 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
175 ((inode)->i_flags & S_SYNC))
176 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
177 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
178 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
179 #define IS_NOATIME(inode) __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
180 #define IS_I_VERSION(inode) __IS_FLG(inode, MS_I_VERSION)
182 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
183 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
184 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
185 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
187 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
188 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
189 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
190 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
192 /* the read-only stuff doesn't really belong here, but any other place is
193 probably as bad and I don't want to create yet another include file. */
195 #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
196 #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
197 #define BLKRRPART _IO(0x12,95) /* re-read partition table */
198 #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
199 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
200 #define BLKRASET _IO(0x12,98) /* set read ahead for block device */
201 #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
202 #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
203 #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
204 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
205 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
206 #define BLKSSZGET _IO(0x12,104)/* get block device sector size */
207 #if 0
208 #define BLKPG _IO(0x12,105)/* See blkpg.h */
210 /* Some people are morons. Do not use sizeof! */
212 #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
213 #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
214 /* This was here just to show that the number is taken -
215 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
216 #endif
217 /* A jump here: 108-111 have been used for various private purposes. */
218 #define BLKBSZGET _IOR(0x12,112,size_t)
219 #define BLKBSZSET _IOW(0x12,113,size_t)
220 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
221 #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
222 #define BLKTRACESTART _IO(0x12,116)
223 #define BLKTRACESTOP _IO(0x12,117)
224 #define BLKTRACETEARDOWN _IO(0x12,118)
226 #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
227 #define FIBMAP _IO(0x00,1) /* bmap access */
228 #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
230 #define FS_IOC_GETFLAGS _IOR('f', 1, long)
231 #define FS_IOC_SETFLAGS _IOW('f', 2, long)
232 #define FS_IOC_GETVERSION _IOR('v', 1, long)
233 #define FS_IOC_SETVERSION _IOW('v', 2, long)
234 #define FS_IOC32_GETFLAGS _IOR('f', 1, int)
235 #define FS_IOC32_SETFLAGS _IOW('f', 2, int)
236 #define FS_IOC32_GETVERSION _IOR('v', 1, int)
237 #define FS_IOC32_SETVERSION _IOW('v', 2, int)
240 * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
242 #define FS_SECRM_FL 0x00000001 /* Secure deletion */
243 #define FS_UNRM_FL 0x00000002 /* Undelete */
244 #define FS_COMPR_FL 0x00000004 /* Compress file */
245 #define FS_SYNC_FL 0x00000008 /* Synchronous updates */
246 #define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */
247 #define FS_APPEND_FL 0x00000020 /* writes to file may only append */
248 #define FS_NODUMP_FL 0x00000040 /* do not dump file */
249 #define FS_NOATIME_FL 0x00000080 /* do not update atime */
250 /* Reserved for compression usage... */
251 #define FS_DIRTY_FL 0x00000100
252 #define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
253 #define FS_NOCOMP_FL 0x00000400 /* Don't compress */
254 #define FS_ECOMPR_FL 0x00000800 /* Compression error */
255 /* End compression flags --- maybe not all used */
256 #define FS_BTREE_FL 0x00001000 /* btree format dir */
257 #define FS_INDEX_FL 0x00001000 /* hash-indexed directory */
258 #define FS_IMAGIC_FL 0x00002000 /* AFS directory */
259 #define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
260 #define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */
261 #define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
262 #define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
263 #define FS_EXTENT_FL 0x00080000 /* Extents */
264 #define FS_DIRECTIO_FL 0x00100000 /* Use direct i/o */
265 #define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
267 #define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
268 #define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
271 #define SYNC_FILE_RANGE_WAIT_BEFORE 1
272 #define SYNC_FILE_RANGE_WRITE 2
273 #define SYNC_FILE_RANGE_WAIT_AFTER 4
275 #ifdef __KERNEL__
277 #include <linux/linkage.h>
278 #include <linux/wait.h>
279 #include <linux/types.h>
280 #include <linux/kdev_t.h>
281 #include <linux/dcache.h>
282 #include <linux/path.h>
283 #include <linux/stat.h>
284 #include <linux/cache.h>
285 #include <linux/kobject.h>
286 #include <linux/list.h>
287 #include <linux/radix-tree.h>
288 #include <linux/prio_tree.h>
289 #include <linux/init.h>
290 #include <linux/pid.h>
291 #include <linux/mutex.h>
292 #include <linux/capability.h>
293 #include <linux/semaphore.h>
295 #include <asm/atomic.h>
296 #include <asm/byteorder.h>
298 struct export_operations;
299 struct hd_geometry;
300 struct iovec;
301 struct nameidata;
302 struct kiocb;
303 struct pipe_inode_info;
304 struct poll_table_struct;
305 struct kstatfs;
306 struct vm_area_struct;
307 struct vfsmount;
309 extern void __init inode_init(void);
310 extern void __init inode_init_early(void);
311 extern void __init files_init(unsigned long);
313 struct buffer_head;
314 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
315 struct buffer_head *bh_result, int create);
316 typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
317 ssize_t bytes, void *private);
320 * Attribute flags. These should be or-ed together to figure out what
321 * has been changed!
323 #define ATTR_MODE (1 << 0)
324 #define ATTR_UID (1 << 1)
325 #define ATTR_GID (1 << 2)
326 #define ATTR_SIZE (1 << 3)
327 #define ATTR_ATIME (1 << 4)
328 #define ATTR_MTIME (1 << 5)
329 #define ATTR_CTIME (1 << 6)
330 #define ATTR_ATIME_SET (1 << 7)
331 #define ATTR_MTIME_SET (1 << 8)
332 #define ATTR_FORCE (1 << 9) /* Not a change, but a change it */
333 #define ATTR_ATTR_FLAG (1 << 10)
334 #define ATTR_KILL_SUID (1 << 11)
335 #define ATTR_KILL_SGID (1 << 12)
336 #define ATTR_FILE (1 << 13)
337 #define ATTR_KILL_PRIV (1 << 14)
338 #define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
339 #define ATTR_TIMES_SET (1 << 16)
342 * This is the Inode Attributes structure, used for notify_change(). It
343 * uses the above definitions as flags, to know which values have changed.
344 * Also, in this manner, a Filesystem can look at only the values it cares
345 * about. Basically, these are the attributes that the VFS layer can
346 * request to change from the FS layer.
348 * Derek Atkins <warlord@MIT.EDU> 94-10-20
350 struct iattr {
351 unsigned int ia_valid;
352 umode_t ia_mode;
353 uid_t ia_uid;
354 gid_t ia_gid;
355 loff_t ia_size;
356 struct timespec ia_atime;
357 struct timespec ia_mtime;
358 struct timespec ia_ctime;
361 * Not an attribute, but an auxilary info for filesystems wanting to
362 * implement an ftruncate() like method. NOTE: filesystem should
363 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
365 struct file *ia_file;
369 * Includes for diskquotas.
371 #include <linux/quota.h>
373 /**
374 * enum positive_aop_returns - aop return codes with specific semantics
376 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
377 * completed, that the page is still locked, and
378 * should be considered active. The VM uses this hint
379 * to return the page to the active list -- it won't
380 * be a candidate for writeback again in the near
381 * future. Other callers must be careful to unlock
382 * the page if they get this return. Returned by
383 * writepage();
385 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
386 * unlocked it and the page might have been truncated.
387 * The caller should back up to acquiring a new page and
388 * trying again. The aop will be taking reasonable
389 * precautions not to livelock. If the caller held a page
390 * reference, it should drop it before retrying. Returned
391 * by readpage().
393 * address_space_operation functions return these large constants to indicate
394 * special semantics to the caller. These are much larger than the bytes in a
395 * page to allow for functions that return the number of bytes operated on in a
396 * given page.
399 enum positive_aop_returns {
400 AOP_WRITEPAGE_ACTIVATE = 0x80000,
401 AOP_TRUNCATED_PAGE = 0x80001,
404 #define AOP_FLAG_UNINTERRUPTIBLE 0x0001 /* will not do a short write */
405 #define AOP_FLAG_CONT_EXPAND 0x0002 /* called from cont_expand */
408 * oh the beauties of C type declarations.
410 struct page;
411 struct address_space;
412 struct writeback_control;
414 struct iov_iter {
415 const struct iovec *iov;
416 unsigned long nr_segs;
417 size_t iov_offset;
418 size_t count;
421 size_t iov_iter_copy_from_user_atomic(struct page *page,
422 struct iov_iter *i, unsigned long offset, size_t bytes);
423 size_t iov_iter_copy_from_user(struct page *page,
424 struct iov_iter *i, unsigned long offset, size_t bytes);
425 void iov_iter_advance(struct iov_iter *i, size_t bytes);
426 int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes);
427 size_t iov_iter_single_seg_count(struct iov_iter *i);
429 static inline void iov_iter_init(struct iov_iter *i,
430 const struct iovec *iov, unsigned long nr_segs,
431 size_t count, size_t written)
433 i->iov = iov;
434 i->nr_segs = nr_segs;
435 i->iov_offset = 0;
436 i->count = count + written;
438 iov_iter_advance(i, written);
441 static inline size_t iov_iter_count(struct iov_iter *i)
443 return i->count;
447 * "descriptor" for what we're up to with a read.
448 * This allows us to use the same read code yet
449 * have multiple different users of the data that
450 * we read from a file.
452 * The simplest case just copies the data to user
453 * mode.
455 typedef struct {
456 size_t written;
457 size_t count;
458 union {
459 char __user *buf;
460 void *data;
461 } arg;
462 int error;
463 } read_descriptor_t;
465 typedef int (*read_actor_t)(read_descriptor_t *, struct page *,
466 unsigned long, unsigned long);
468 struct address_space_operations {
469 int (*writepage)(struct page *page, struct writeback_control *wbc);
470 int (*readpage)(struct file *, struct page *);
471 void (*sync_page)(struct page *);
473 /* Write back some dirty pages from this mapping. */
474 int (*writepages)(struct address_space *, struct writeback_control *);
476 /* Set a page dirty. Return true if this dirtied it */
477 int (*set_page_dirty)(struct page *page);
479 int (*readpages)(struct file *filp, struct address_space *mapping,
480 struct list_head *pages, unsigned nr_pages);
483 * ext3 requires that a successful prepare_write() call be followed
484 * by a commit_write() call - they must be balanced
486 int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
487 int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
489 int (*write_begin)(struct file *, struct address_space *mapping,
490 loff_t pos, unsigned len, unsigned flags,
491 struct page **pagep, void **fsdata);
492 int (*write_end)(struct file *, struct address_space *mapping,
493 loff_t pos, unsigned len, unsigned copied,
494 struct page *page, void *fsdata);
496 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
497 sector_t (*bmap)(struct address_space *, sector_t);
498 void (*invalidatepage) (struct page *, unsigned long);
499 int (*releasepage) (struct page *, gfp_t);
500 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
501 loff_t offset, unsigned long nr_segs);
502 int (*get_xip_mem)(struct address_space *, pgoff_t, int,
503 void **, unsigned long *);
504 /* migrate the contents of a page to the specified target */
505 int (*migratepage) (struct address_space *,
506 struct page *, struct page *);
507 int (*launder_page) (struct page *);
508 int (*is_partially_uptodate) (struct page *, read_descriptor_t *,
509 unsigned long);
513 * pagecache_write_begin/pagecache_write_end must be used by general code
514 * to write into the pagecache.
516 int pagecache_write_begin(struct file *, struct address_space *mapping,
517 loff_t pos, unsigned len, unsigned flags,
518 struct page **pagep, void **fsdata);
520 int pagecache_write_end(struct file *, struct address_space *mapping,
521 loff_t pos, unsigned len, unsigned copied,
522 struct page *page, void *fsdata);
524 struct backing_dev_info;
525 struct address_space {
526 struct inode *host; /* owner: inode, block_device */
527 struct radix_tree_root page_tree; /* radix tree of all pages */
528 spinlock_t tree_lock; /* and lock protecting it */
529 unsigned int i_mmap_writable;/* count VM_SHARED mappings */
530 struct prio_tree_root i_mmap; /* tree of private and shared mappings */
531 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
532 spinlock_t i_mmap_lock; /* protect tree, count, list */
533 unsigned int truncate_count; /* Cover race condition with truncate */
534 unsigned long nrpages; /* number of total pages */
535 pgoff_t writeback_index;/* writeback starts here */
536 const struct address_space_operations *a_ops; /* methods */
537 unsigned long flags; /* error bits/gfp mask */
538 struct backing_dev_info *backing_dev_info; /* device readahead, etc */
539 spinlock_t private_lock; /* for use by the address_space */
540 struct list_head private_list; /* ditto */
541 struct address_space *assoc_mapping; /* ditto */
542 } __attribute__((aligned(sizeof(long))));
544 * On most architectures that alignment is already the case; but
545 * must be enforced here for CRIS, to let the least signficant bit
546 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
549 struct block_device {
550 dev_t bd_dev; /* not a kdev_t - it's a search key */
551 struct inode * bd_inode; /* will die */
552 int bd_openers;
553 struct mutex bd_mutex; /* open/close mutex */
554 struct semaphore bd_mount_sem;
555 struct list_head bd_inodes;
556 void * bd_holder;
557 int bd_holders;
558 #ifdef CONFIG_SYSFS
559 struct list_head bd_holder_list;
560 #endif
561 struct block_device * bd_contains;
562 unsigned bd_block_size;
563 struct hd_struct * bd_part;
564 /* number of times partitions within this device have been opened. */
565 unsigned bd_part_count;
566 int bd_invalidated;
567 struct gendisk * bd_disk;
568 struct list_head bd_list;
569 struct backing_dev_info *bd_inode_backing_dev_info;
571 * Private data. You must have bd_claim'ed the block_device
572 * to use this. NOTE: bd_claim allows an owner to claim
573 * the same device multiple times, the owner must take special
574 * care to not mess up bd_private for that case.
576 unsigned long bd_private;
580 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
581 * radix trees
583 #define PAGECACHE_TAG_DIRTY 0
584 #define PAGECACHE_TAG_WRITEBACK 1
586 int mapping_tagged(struct address_space *mapping, int tag);
589 * Might pages of this file be mapped into userspace?
591 static inline int mapping_mapped(struct address_space *mapping)
593 return !prio_tree_empty(&mapping->i_mmap) ||
594 !list_empty(&mapping->i_mmap_nonlinear);
598 * Might pages of this file have been modified in userspace?
599 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
600 * marks vma as VM_SHARED if it is shared, and the file was opened for
601 * writing i.e. vma may be mprotected writable even if now readonly.
603 static inline int mapping_writably_mapped(struct address_space *mapping)
605 return mapping->i_mmap_writable != 0;
609 * Use sequence counter to get consistent i_size on 32-bit processors.
611 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
612 #include <linux/seqlock.h>
613 #define __NEED_I_SIZE_ORDERED
614 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
615 #else
616 #define i_size_ordered_init(inode) do { } while (0)
617 #endif
619 struct inode {
620 struct hlist_node i_hash;
621 struct list_head i_list;
622 struct list_head i_sb_list;
623 struct list_head i_dentry;
624 unsigned long i_ino;
625 atomic_t i_count;
626 unsigned int i_nlink;
627 uid_t i_uid;
628 gid_t i_gid;
629 dev_t i_rdev;
630 u64 i_version;
631 loff_t i_size;
632 #ifdef __NEED_I_SIZE_ORDERED
633 seqcount_t i_size_seqcount;
634 #endif
635 struct timespec i_atime;
636 struct timespec i_mtime;
637 struct timespec i_ctime;
638 unsigned int i_blkbits;
639 blkcnt_t i_blocks;
640 unsigned short i_bytes;
641 umode_t i_mode;
642 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
643 struct mutex i_mutex;
644 struct rw_semaphore i_alloc_sem;
645 const struct inode_operations *i_op;
646 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
647 struct super_block *i_sb;
648 struct file_lock *i_flock;
649 struct address_space *i_mapping;
650 struct address_space i_data;
651 #ifdef CONFIG_QUOTA
652 struct dquot *i_dquot[MAXQUOTAS];
653 #endif
654 struct list_head i_devices;
655 union {
656 struct pipe_inode_info *i_pipe;
657 struct block_device *i_bdev;
658 struct cdev *i_cdev;
660 int i_cindex;
662 __u32 i_generation;
664 #ifdef CONFIG_DNOTIFY
665 unsigned long i_dnotify_mask; /* Directory notify events */
666 struct dnotify_struct *i_dnotify; /* for directory notifications */
667 #endif
669 #ifdef CONFIG_INOTIFY
670 struct list_head inotify_watches; /* watches on this inode */
671 struct mutex inotify_mutex; /* protects the watches list */
672 #endif
674 unsigned long i_state;
675 unsigned long dirtied_when; /* jiffies of first dirtying */
677 unsigned int i_flags;
679 atomic_t i_writecount;
680 #ifdef CONFIG_SECURITY
681 void *i_security;
682 #endif
683 void *i_private; /* fs or device private pointer */
687 * inode->i_mutex nesting subclasses for the lock validator:
689 * 0: the object of the current VFS operation
690 * 1: parent
691 * 2: child/target
692 * 3: quota file
694 * The locking order between these classes is
695 * parent -> child -> normal -> xattr -> quota
697 enum inode_i_mutex_lock_class
699 I_MUTEX_NORMAL,
700 I_MUTEX_PARENT,
701 I_MUTEX_CHILD,
702 I_MUTEX_XATTR,
703 I_MUTEX_QUOTA
706 extern void inode_double_lock(struct inode *inode1, struct inode *inode2);
707 extern void inode_double_unlock(struct inode *inode1, struct inode *inode2);
710 * NOTE: in a 32bit arch with a preemptable kernel and
711 * an UP compile the i_size_read/write must be atomic
712 * with respect to the local cpu (unlike with preempt disabled),
713 * but they don't need to be atomic with respect to other cpus like in
714 * true SMP (so they need either to either locally disable irq around
715 * the read or for example on x86 they can be still implemented as a
716 * cmpxchg8b without the need of the lock prefix). For SMP compiles
717 * and 64bit archs it makes no difference if preempt is enabled or not.
719 static inline loff_t i_size_read(const struct inode *inode)
721 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
722 loff_t i_size;
723 unsigned int seq;
725 do {
726 seq = read_seqcount_begin(&inode->i_size_seqcount);
727 i_size = inode->i_size;
728 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
729 return i_size;
730 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
731 loff_t i_size;
733 preempt_disable();
734 i_size = inode->i_size;
735 preempt_enable();
736 return i_size;
737 #else
738 return inode->i_size;
739 #endif
743 * NOTE: unlike i_size_read(), i_size_write() does need locking around it
744 * (normally i_mutex), otherwise on 32bit/SMP an update of i_size_seqcount
745 * can be lost, resulting in subsequent i_size_read() calls spinning forever.
747 static inline void i_size_write(struct inode *inode, loff_t i_size)
749 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
750 write_seqcount_begin(&inode->i_size_seqcount);
751 inode->i_size = i_size;
752 write_seqcount_end(&inode->i_size_seqcount);
753 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
754 preempt_disable();
755 inode->i_size = i_size;
756 preempt_enable();
757 #else
758 inode->i_size = i_size;
759 #endif
762 static inline unsigned iminor(const struct inode *inode)
764 return MINOR(inode->i_rdev);
767 static inline unsigned imajor(const struct inode *inode)
769 return MAJOR(inode->i_rdev);
772 extern struct block_device *I_BDEV(struct inode *inode);
774 struct fown_struct {
775 rwlock_t lock; /* protects pid, uid, euid fields */
776 struct pid *pid; /* pid or -pgrp where SIGIO should be sent */
777 enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
778 uid_t uid, euid; /* uid/euid of process setting the owner */
779 int signum; /* posix.1b rt signal to be delivered on IO */
783 * Track a single file's readahead state
785 struct file_ra_state {
786 pgoff_t start; /* where readahead started */
787 unsigned int size; /* # of readahead pages */
788 unsigned int async_size; /* do asynchronous readahead when
789 there are only # of pages ahead */
791 unsigned int ra_pages; /* Maximum readahead window */
792 int mmap_miss; /* Cache miss stat for mmap accesses */
793 loff_t prev_pos; /* Cache last read() position */
797 * Check if @index falls in the readahead windows.
799 static inline int ra_has_index(struct file_ra_state *ra, pgoff_t index)
801 return (index >= ra->start &&
802 index < ra->start + ra->size);
805 #define FILE_MNT_WRITE_TAKEN 1
806 #define FILE_MNT_WRITE_RELEASED 2
808 struct file {
810 * fu_list becomes invalid after file_free is called and queued via
811 * fu_rcuhead for RCU freeing
813 union {
814 struct list_head fu_list;
815 struct rcu_head fu_rcuhead;
816 } f_u;
817 struct path f_path;
818 #define f_dentry f_path.dentry
819 #define f_vfsmnt f_path.mnt
820 const struct file_operations *f_op;
821 atomic_long_t f_count;
822 unsigned int f_flags;
823 mode_t f_mode;
824 loff_t f_pos;
825 struct fown_struct f_owner;
826 unsigned int f_uid, f_gid;
827 struct file_ra_state f_ra;
829 u64 f_version;
830 #ifdef CONFIG_SECURITY
831 void *f_security;
832 #endif
833 /* needed for tty driver, and maybe others */
834 void *private_data;
836 #ifdef CONFIG_EPOLL
837 /* Used by fs/eventpoll.c to link all the hooks to this file */
838 struct list_head f_ep_links;
839 spinlock_t f_ep_lock;
840 #endif /* #ifdef CONFIG_EPOLL */
841 struct address_space *f_mapping;
842 #ifdef CONFIG_DEBUG_WRITECOUNT
843 unsigned long f_mnt_write_state;
844 #endif
846 extern spinlock_t files_lock;
847 #define file_list_lock() spin_lock(&files_lock);
848 #define file_list_unlock() spin_unlock(&files_lock);
850 #define get_file(x) atomic_long_inc(&(x)->f_count)
851 #define file_count(x) atomic_long_read(&(x)->f_count)
853 #ifdef CONFIG_DEBUG_WRITECOUNT
854 static inline void file_take_write(struct file *f)
856 WARN_ON(f->f_mnt_write_state != 0);
857 f->f_mnt_write_state = FILE_MNT_WRITE_TAKEN;
859 static inline void file_release_write(struct file *f)
861 f->f_mnt_write_state |= FILE_MNT_WRITE_RELEASED;
863 static inline void file_reset_write(struct file *f)
865 f->f_mnt_write_state = 0;
867 static inline void file_check_state(struct file *f)
870 * At this point, either both or neither of these bits
871 * should be set.
873 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN);
874 WARN_ON(f->f_mnt_write_state == FILE_MNT_WRITE_RELEASED);
876 static inline int file_check_writeable(struct file *f)
878 if (f->f_mnt_write_state == FILE_MNT_WRITE_TAKEN)
879 return 0;
880 printk(KERN_WARNING "writeable file with no "
881 "mnt_want_write()\n");
882 WARN_ON(1);
883 return -EINVAL;
885 #else /* !CONFIG_DEBUG_WRITECOUNT */
886 static inline void file_take_write(struct file *filp) {}
887 static inline void file_release_write(struct file *filp) {}
888 static inline void file_reset_write(struct file *filp) {}
889 static inline void file_check_state(struct file *filp) {}
890 static inline int file_check_writeable(struct file *filp)
892 return 0;
894 #endif /* CONFIG_DEBUG_WRITECOUNT */
896 #define MAX_NON_LFS ((1UL<<31) - 1)
898 /* Page cache limit. The filesystems should put that into their s_maxbytes
899 limits, otherwise bad things can happen in VM. */
900 #if BITS_PER_LONG==32
901 #define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
902 #elif BITS_PER_LONG==64
903 #define MAX_LFS_FILESIZE 0x7fffffffffffffffUL
904 #endif
906 #define FL_POSIX 1
907 #define FL_FLOCK 2
908 #define FL_ACCESS 8 /* not trying to lock, just looking */
909 #define FL_EXISTS 16 /* when unlocking, test for existence */
910 #define FL_LEASE 32 /* lease held on this file */
911 #define FL_CLOSE 64 /* unlock on close */
912 #define FL_SLEEP 128 /* A blocking lock */
915 * Special return value from posix_lock_file() and vfs_lock_file() for
916 * asynchronous locking.
918 #define FILE_LOCK_DEFERRED 1
921 * The POSIX file lock owner is determined by
922 * the "struct files_struct" in the thread group
923 * (or NULL for no owner - BSD locks).
925 * Lockd stuffs a "host" pointer into this.
927 typedef struct files_struct *fl_owner_t;
929 struct file_lock_operations {
930 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
931 void (*fl_release_private)(struct file_lock *);
934 struct lock_manager_operations {
935 int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
936 void (*fl_notify)(struct file_lock *); /* unblock callback */
937 int (*fl_grant)(struct file_lock *, struct file_lock *, int);
938 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
939 void (*fl_release_private)(struct file_lock *);
940 void (*fl_break)(struct file_lock *);
941 int (*fl_mylease)(struct file_lock *, struct file_lock *);
942 int (*fl_change)(struct file_lock **, int);
945 /* that will die - we need it for nfs_lock_info */
946 #include <linux/nfs_fs_i.h>
948 struct file_lock {
949 struct file_lock *fl_next; /* singly linked list for this inode */
950 struct list_head fl_link; /* doubly linked list of all locks */
951 struct list_head fl_block; /* circular list of blocked processes */
952 fl_owner_t fl_owner;
953 unsigned char fl_flags;
954 unsigned char fl_type;
955 unsigned int fl_pid;
956 struct pid *fl_nspid;
957 wait_queue_head_t fl_wait;
958 struct file *fl_file;
959 loff_t fl_start;
960 loff_t fl_end;
962 struct fasync_struct * fl_fasync; /* for lease break notifications */
963 unsigned long fl_break_time; /* for nonblocking lease breaks */
965 struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
966 struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
967 union {
968 struct nfs_lock_info nfs_fl;
969 struct nfs4_lock_info nfs4_fl;
970 struct {
971 struct list_head link; /* link in AFS vnode's pending_locks list */
972 int state; /* state of grant or error if -ve */
973 } afs;
974 } fl_u;
977 /* The following constant reflects the upper bound of the file/locking space */
978 #ifndef OFFSET_MAX
979 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
980 #define OFFSET_MAX INT_LIMIT(loff_t)
981 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
982 #endif
984 #include <linux/fcntl.h>
986 extern int fcntl_getlk(struct file *, struct flock __user *);
987 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
988 struct flock __user *);
990 #if BITS_PER_LONG == 32
991 extern int fcntl_getlk64(struct file *, struct flock64 __user *);
992 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
993 struct flock64 __user *);
994 #endif
996 extern void send_sigio(struct fown_struct *fown, int fd, int band);
997 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
998 extern int fcntl_getlease(struct file *filp);
1000 /* fs/sync.c */
1001 extern int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
1002 loff_t endbyte, unsigned int flags);
1004 /* fs/locks.c */
1005 extern void locks_init_lock(struct file_lock *);
1006 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
1007 extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);
1008 extern void locks_remove_posix(struct file *, fl_owner_t);
1009 extern void locks_remove_flock(struct file *);
1010 extern void posix_test_lock(struct file *, struct file_lock *);
1011 extern int posix_lock_file(struct file *, struct file_lock *, struct file_lock *);
1012 extern int posix_lock_file_wait(struct file *, struct file_lock *);
1013 extern int posix_unblock_lock(struct file *, struct file_lock *);
1014 extern int vfs_test_lock(struct file *, struct file_lock *);
1015 extern int vfs_lock_file(struct file *, unsigned int, struct file_lock *, struct file_lock *);
1016 extern int vfs_cancel_lock(struct file *filp, struct file_lock *fl);
1017 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
1018 extern int __break_lease(struct inode *inode, unsigned int flags);
1019 extern void lease_get_mtime(struct inode *, struct timespec *time);
1020 extern int generic_setlease(struct file *, long, struct file_lock **);
1021 extern int vfs_setlease(struct file *, long, struct file_lock **);
1022 extern int lease_modify(struct file_lock **, int);
1023 extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
1024 extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
1025 extern struct seq_operations locks_seq_operations;
1027 struct fasync_struct {
1028 int magic;
1029 int fa_fd;
1030 struct fasync_struct *fa_next; /* singly linked list */
1031 struct file *fa_file;
1034 #define FASYNC_MAGIC 0x4601
1036 /* SMP safe fasync helpers: */
1037 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
1038 /* can be called from interrupts */
1039 extern void kill_fasync(struct fasync_struct **, int, int);
1040 /* only for net: no internal synchronization */
1041 extern void __kill_fasync(struct fasync_struct *, int, int);
1043 extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
1044 extern int f_setown(struct file *filp, unsigned long arg, int force);
1045 extern void f_delown(struct file *filp);
1046 extern pid_t f_getown(struct file *filp);
1047 extern int send_sigurg(struct fown_struct *fown);
1050 * Umount options
1053 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
1054 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
1055 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
1057 extern struct list_head super_blocks;
1058 extern spinlock_t sb_lock;
1060 #define sb_entry(list) list_entry((list), struct super_block, s_list)
1061 #define S_BIAS (1<<30)
1062 struct super_block {
1063 struct list_head s_list; /* Keep this first */
1064 dev_t s_dev; /* search index; _not_ kdev_t */
1065 unsigned long s_blocksize;
1066 unsigned char s_blocksize_bits;
1067 unsigned char s_dirt;
1068 unsigned long long s_maxbytes; /* Max file size */
1069 struct file_system_type *s_type;
1070 const struct super_operations *s_op;
1071 struct dquot_operations *dq_op;
1072 struct quotactl_ops *s_qcop;
1073 const struct export_operations *s_export_op;
1074 unsigned long s_flags;
1075 unsigned long s_magic;
1076 struct dentry *s_root;
1077 struct rw_semaphore s_umount;
1078 struct mutex s_lock;
1079 int s_count;
1080 int s_syncing;
1081 int s_need_sync_fs;
1082 atomic_t s_active;
1083 #ifdef CONFIG_SECURITY
1084 void *s_security;
1085 #endif
1086 struct xattr_handler **s_xattr;
1088 struct list_head s_inodes; /* all inodes */
1089 struct list_head s_dirty; /* dirty inodes */
1090 struct list_head s_io; /* parked for writeback */
1091 struct list_head s_more_io; /* parked for more writeback */
1092 struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */
1093 struct list_head s_files;
1094 /* s_dentry_lru and s_nr_dentry_unused are protected by dcache_lock */
1095 struct list_head s_dentry_lru; /* unused dentry lru */
1096 int s_nr_dentry_unused; /* # of dentry on lru */
1098 struct block_device *s_bdev;
1099 struct mtd_info *s_mtd;
1100 struct list_head s_instances;
1101 struct quota_info s_dquot; /* Diskquota specific options */
1103 int s_frozen;
1104 wait_queue_head_t s_wait_unfrozen;
1106 char s_id[32]; /* Informational name */
1108 void *s_fs_info; /* Filesystem private info */
1111 * The next field is for VFS *only*. No filesystems have any business
1112 * even looking at it. You had been warned.
1114 struct mutex s_vfs_rename_mutex; /* Kludge */
1116 /* Granularity of c/m/atime in ns.
1117 Cannot be worse than a second */
1118 u32 s_time_gran;
1121 * Filesystem subtype. If non-empty the filesystem type field
1122 * in /proc/mounts will be "type.subtype"
1124 char *s_subtype;
1127 * Saved mount options for lazy filesystems using
1128 * generic_show_options()
1130 char *s_options;
1133 extern struct timespec current_fs_time(struct super_block *sb);
1136 * Snapshotting support.
1138 enum {
1139 SB_UNFROZEN = 0,
1140 SB_FREEZE_WRITE = 1,
1141 SB_FREEZE_TRANS = 2,
1144 #define vfs_check_frozen(sb, level) \
1145 wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level)))
1147 #define get_fs_excl() atomic_inc(&current->fs_excl)
1148 #define put_fs_excl() atomic_dec(&current->fs_excl)
1149 #define has_fs_excl() atomic_read(&current->fs_excl)
1151 #define is_owner_or_cap(inode) \
1152 ((current->fsuid == (inode)->i_uid) || capable(CAP_FOWNER))
1154 /* not quite ready to be deprecated, but... */
1155 extern void lock_super(struct super_block *);
1156 extern void unlock_super(struct super_block *);
1159 * VFS helper functions..
1161 extern int vfs_permission(struct nameidata *, int);
1162 extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
1163 extern int vfs_mkdir(struct inode *, struct dentry *, int);
1164 extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
1165 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
1166 extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
1167 extern int vfs_rmdir(struct inode *, struct dentry *);
1168 extern int vfs_unlink(struct inode *, struct dentry *);
1169 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1172 * VFS dentry helper functions.
1174 extern void dentry_unhash(struct dentry *dentry);
1177 * VFS file helper functions.
1179 extern int file_permission(struct file *, int);
1182 * File types
1184 * NOTE! These match bits 12..15 of stat.st_mode
1185 * (ie "(i_mode >> 12) & 15").
1187 #define DT_UNKNOWN 0
1188 #define DT_FIFO 1
1189 #define DT_CHR 2
1190 #define DT_DIR 4
1191 #define DT_BLK 6
1192 #define DT_REG 8
1193 #define DT_LNK 10
1194 #define DT_SOCK 12
1195 #define DT_WHT 14
1197 #define OSYNC_METADATA (1<<0)
1198 #define OSYNC_DATA (1<<1)
1199 #define OSYNC_INODE (1<<2)
1200 int generic_osync_inode(struct inode *, struct address_space *, int);
1203 * This is the "filldir" function type, used by readdir() to let
1204 * the kernel specify what kind of dirent layout it wants to have.
1205 * This allows the kernel to read directories into kernel space or
1206 * to have different dirent layouts depending on the binary type.
1208 typedef int (*filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
1210 struct block_device_operations {
1211 int (*open) (struct inode *, struct file *);
1212 int (*release) (struct inode *, struct file *);
1213 int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
1214 long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
1215 long (*compat_ioctl) (struct file *, unsigned, unsigned long);
1216 int (*direct_access) (struct block_device *, sector_t,
1217 void **, unsigned long *);
1218 int (*media_changed) (struct gendisk *);
1219 int (*revalidate_disk) (struct gendisk *);
1220 int (*getgeo)(struct block_device *, struct hd_geometry *);
1221 struct module *owner;
1224 /* These macros are for out of kernel modules to test that
1225 * the kernel supports the unlocked_ioctl and compat_ioctl
1226 * fields in struct file_operations. */
1227 #define HAVE_COMPAT_IOCTL 1
1228 #define HAVE_UNLOCKED_IOCTL 1
1231 * NOTE:
1232 * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl
1233 * can be called without the big kernel lock held in all filesystems.
1235 struct file_operations {
1236 struct module *owner;
1237 loff_t (*llseek) (struct file *, loff_t, int);
1238 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1239 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1240 ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1241 ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1242 int (*readdir) (struct file *, void *, filldir_t);
1243 unsigned int (*poll) (struct file *, struct poll_table_struct *);
1244 int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
1245 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1246 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1247 int (*mmap) (struct file *, struct vm_area_struct *);
1248 int (*open) (struct inode *, struct file *);
1249 int (*flush) (struct file *, fl_owner_t id);
1250 int (*release) (struct inode *, struct file *);
1251 int (*fsync) (struct file *, struct dentry *, int datasync);
1252 int (*aio_fsync) (struct kiocb *, int datasync);
1253 int (*fasync) (int, struct file *, int);
1254 int (*lock) (struct file *, int, struct file_lock *);
1255 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1256 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1257 int (*check_flags)(int);
1258 int (*dir_notify)(struct file *filp, unsigned long arg);
1259 int (*flock) (struct file *, int, struct file_lock *);
1260 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1261 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1262 int (*setlease)(struct file *, long, struct file_lock **);
1265 struct inode_operations {
1266 int (*create) (struct inode *,struct dentry *,int, struct nameidata *);
1267 struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
1268 int (*link) (struct dentry *,struct inode *,struct dentry *);
1269 int (*unlink) (struct inode *,struct dentry *);
1270 int (*symlink) (struct inode *,struct dentry *,const char *);
1271 int (*mkdir) (struct inode *,struct dentry *,int);
1272 int (*rmdir) (struct inode *,struct dentry *);
1273 int (*mknod) (struct inode *,struct dentry *,int,dev_t);
1274 int (*rename) (struct inode *, struct dentry *,
1275 struct inode *, struct dentry *);
1276 int (*readlink) (struct dentry *, char __user *,int);
1277 void * (*follow_link) (struct dentry *, struct nameidata *);
1278 void (*put_link) (struct dentry *, struct nameidata *, void *);
1279 void (*truncate) (struct inode *);
1280 int (*permission) (struct inode *, int);
1281 int (*setattr) (struct dentry *, struct iattr *);
1282 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
1283 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
1284 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
1285 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1286 int (*removexattr) (struct dentry *, const char *);
1287 void (*truncate_range)(struct inode *, loff_t, loff_t);
1288 long (*fallocate)(struct inode *inode, int mode, loff_t offset,
1289 loff_t len);
1292 struct seq_file;
1294 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
1295 unsigned long nr_segs, unsigned long fast_segs,
1296 struct iovec *fast_pointer,
1297 struct iovec **ret_pointer);
1299 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1300 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1301 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1302 unsigned long, loff_t *);
1303 extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
1304 unsigned long, loff_t *);
1306 struct super_operations {
1307 struct inode *(*alloc_inode)(struct super_block *sb);
1308 void (*destroy_inode)(struct inode *);
1310 void (*dirty_inode) (struct inode *);
1311 int (*write_inode) (struct inode *, int);
1312 void (*drop_inode) (struct inode *);
1313 void (*delete_inode) (struct inode *);
1314 void (*put_super) (struct super_block *);
1315 void (*write_super) (struct super_block *);
1316 int (*sync_fs)(struct super_block *sb, int wait);
1317 void (*write_super_lockfs) (struct super_block *);
1318 void (*unlockfs) (struct super_block *);
1319 int (*statfs) (struct dentry *, struct kstatfs *);
1320 int (*remount_fs) (struct super_block *, int *, char *);
1321 void (*clear_inode) (struct inode *);
1322 void (*umount_begin) (struct super_block *);
1324 int (*show_options)(struct seq_file *, struct vfsmount *);
1325 int (*show_stats)(struct seq_file *, struct vfsmount *);
1326 #ifdef CONFIG_QUOTA
1327 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1328 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1329 #endif
1333 * Inode state bits. Protected by inode_lock.
1335 * Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
1336 * I_DIRTY_DATASYNC and I_DIRTY_PAGES.
1338 * Four bits define the lifetime of an inode. Initially, inodes are I_NEW,
1339 * until that flag is cleared. I_WILL_FREE, I_FREEING and I_CLEAR are set at
1340 * various stages of removing an inode.
1342 * Two bits are used for locking and completion notification, I_LOCK and I_SYNC.
1344 * I_DIRTY_SYNC Inode is dirty, but doesn't have to be written on
1345 * fdatasync(). i_atime is the usual cause.
1346 * I_DIRTY_DATASYNC Data-related inode changes pending. We keep track of
1347 * these changes separately from I_DIRTY_SYNC so that we
1348 * don't have to write inode on fdatasync() when only
1349 * mtime has changed in it.
1350 * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean.
1351 * I_NEW get_new_inode() sets i_state to I_LOCK|I_NEW. Both
1352 * are cleared by unlock_new_inode(), called from iget().
1353 * I_WILL_FREE Must be set when calling write_inode_now() if i_count
1354 * is zero. I_FREEING must be set when I_WILL_FREE is
1355 * cleared.
1356 * I_FREEING Set when inode is about to be freed but still has dirty
1357 * pages or buffers attached or the inode itself is still
1358 * dirty.
1359 * I_CLEAR Set by clear_inode(). In this state the inode is clean
1360 * and can be destroyed.
1362 * Inodes that are I_WILL_FREE, I_FREEING or I_CLEAR are
1363 * prohibited for many purposes. iget() must wait for
1364 * the inode to be completely released, then create it
1365 * anew. Other functions will just ignore such inodes,
1366 * if appropriate. I_LOCK is used for waiting.
1368 * I_LOCK Serves as both a mutex and completion notification.
1369 * New inodes set I_LOCK. If two processes both create
1370 * the same inode, one of them will release its inode and
1371 * wait for I_LOCK to be released before returning.
1372 * Inodes in I_WILL_FREE, I_FREEING or I_CLEAR state can
1373 * also cause waiting on I_LOCK, without I_LOCK actually
1374 * being set. find_inode() uses this to prevent returning
1375 * nearly-dead inodes.
1376 * I_SYNC Similar to I_LOCK, but limited in scope to writeback
1377 * of inode dirty data. Having a separate lock for this
1378 * purpose reduces latency and prevents some filesystem-
1379 * specific deadlocks.
1381 * Q: What is the difference between I_WILL_FREE and I_FREEING?
1382 * Q: igrab() only checks on (I_FREEING|I_WILL_FREE). Should it also check on
1383 * I_CLEAR? If not, why?
1385 #define I_DIRTY_SYNC 1
1386 #define I_DIRTY_DATASYNC 2
1387 #define I_DIRTY_PAGES 4
1388 #define I_NEW 8
1389 #define I_WILL_FREE 16
1390 #define I_FREEING 32
1391 #define I_CLEAR 64
1392 #define __I_LOCK 7
1393 #define I_LOCK (1 << __I_LOCK)
1394 #define __I_SYNC 8
1395 #define I_SYNC (1 << __I_SYNC)
1397 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1399 extern void __mark_inode_dirty(struct inode *, int);
1400 static inline void mark_inode_dirty(struct inode *inode)
1402 __mark_inode_dirty(inode, I_DIRTY);
1405 static inline void mark_inode_dirty_sync(struct inode *inode)
1407 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1411 * inc_nlink - directly increment an inode's link count
1412 * @inode: inode
1414 * This is a low-level filesystem helper to replace any
1415 * direct filesystem manipulation of i_nlink. Currently,
1416 * it is only here for parity with dec_nlink().
1418 static inline void inc_nlink(struct inode *inode)
1420 inode->i_nlink++;
1423 static inline void inode_inc_link_count(struct inode *inode)
1425 inc_nlink(inode);
1426 mark_inode_dirty(inode);
1430 * drop_nlink - directly drop an inode's link count
1431 * @inode: inode
1433 * This is a low-level filesystem helper to replace any
1434 * direct filesystem manipulation of i_nlink. In cases
1435 * where we are attempting to track writes to the
1436 * filesystem, a decrement to zero means an imminent
1437 * write when the file is truncated and actually unlinked
1438 * on the filesystem.
1440 static inline void drop_nlink(struct inode *inode)
1442 inode->i_nlink--;
1446 * clear_nlink - directly zero an inode's link count
1447 * @inode: inode
1449 * This is a low-level filesystem helper to replace any
1450 * direct filesystem manipulation of i_nlink. See
1451 * drop_nlink() for why we care about i_nlink hitting zero.
1453 static inline void clear_nlink(struct inode *inode)
1455 inode->i_nlink = 0;
1458 static inline void inode_dec_link_count(struct inode *inode)
1460 drop_nlink(inode);
1461 mark_inode_dirty(inode);
1465 * inode_inc_iversion - increments i_version
1466 * @inode: inode that need to be updated
1468 * Every time the inode is modified, the i_version field will be incremented.
1469 * The filesystem has to be mounted with i_version flag
1472 static inline void inode_inc_iversion(struct inode *inode)
1474 spin_lock(&inode->i_lock);
1475 inode->i_version++;
1476 spin_unlock(&inode->i_lock);
1479 extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry);
1480 static inline void file_accessed(struct file *file)
1482 if (!(file->f_flags & O_NOATIME))
1483 touch_atime(file->f_path.mnt, file->f_path.dentry);
1486 int sync_inode(struct inode *inode, struct writeback_control *wbc);
1488 struct file_system_type {
1489 const char *name;
1490 int fs_flags;
1491 int (*get_sb) (struct file_system_type *, int,
1492 const char *, void *, struct vfsmount *);
1493 void (*kill_sb) (struct super_block *);
1494 struct module *owner;
1495 struct file_system_type * next;
1496 struct list_head fs_supers;
1498 struct lock_class_key s_lock_key;
1499 struct lock_class_key s_umount_key;
1501 struct lock_class_key i_lock_key;
1502 struct lock_class_key i_mutex_key;
1503 struct lock_class_key i_mutex_dir_key;
1504 struct lock_class_key i_alloc_sem_key;
1507 extern int get_sb_bdev(struct file_system_type *fs_type,
1508 int flags, const char *dev_name, void *data,
1509 int (*fill_super)(struct super_block *, void *, int),
1510 struct vfsmount *mnt);
1511 extern int get_sb_single(struct file_system_type *fs_type,
1512 int flags, void *data,
1513 int (*fill_super)(struct super_block *, void *, int),
1514 struct vfsmount *mnt);
1515 extern int get_sb_nodev(struct file_system_type *fs_type,
1516 int flags, void *data,
1517 int (*fill_super)(struct super_block *, void *, int),
1518 struct vfsmount *mnt);
1519 void generic_shutdown_super(struct super_block *sb);
1520 void kill_block_super(struct super_block *sb);
1521 void kill_anon_super(struct super_block *sb);
1522 void kill_litter_super(struct super_block *sb);
1523 void deactivate_super(struct super_block *sb);
1524 int set_anon_super(struct super_block *s, void *data);
1525 struct super_block *sget(struct file_system_type *type,
1526 int (*test)(struct super_block *,void *),
1527 int (*set)(struct super_block *,void *),
1528 void *data);
1529 extern int get_sb_pseudo(struct file_system_type *, char *,
1530 const struct super_operations *ops, unsigned long,
1531 struct vfsmount *mnt);
1532 extern int simple_set_mnt(struct vfsmount *mnt, struct super_block *sb);
1533 int __put_super_and_need_restart(struct super_block *sb);
1534 void unnamed_dev_init(void);
1536 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
1537 #define fops_get(fops) \
1538 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
1539 #define fops_put(fops) \
1540 do { if (fops) module_put((fops)->owner); } while(0)
1542 extern int register_filesystem(struct file_system_type *);
1543 extern int unregister_filesystem(struct file_system_type *);
1544 extern struct vfsmount *kern_mount_data(struct file_system_type *, void *data);
1545 #define kern_mount(type) kern_mount_data(type, NULL)
1546 extern int may_umount_tree(struct vfsmount *);
1547 extern int may_umount(struct vfsmount *);
1548 extern long do_mount(char *, char *, char *, unsigned long, void *);
1549 extern struct vfsmount *collect_mounts(struct vfsmount *, struct dentry *);
1550 extern void drop_collected_mounts(struct vfsmount *);
1552 extern int vfs_statfs(struct dentry *, struct kstatfs *);
1554 /* /sys/fs */
1555 extern struct kobject *fs_kobj;
1557 #define FLOCK_VERIFY_READ 1
1558 #define FLOCK_VERIFY_WRITE 2
1560 extern int locks_mandatory_locked(struct inode *);
1561 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
1564 * Candidates for mandatory locking have the setgid bit set
1565 * but no group execute bit - an otherwise meaningless combination.
1568 static inline int __mandatory_lock(struct inode *ino)
1570 return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
1574 * ... and these candidates should be on MS_MANDLOCK mounted fs,
1575 * otherwise these will be advisory locks
1578 static inline int mandatory_lock(struct inode *ino)
1580 return IS_MANDLOCK(ino) && __mandatory_lock(ino);
1583 static inline int locks_verify_locked(struct inode *inode)
1585 if (mandatory_lock(inode))
1586 return locks_mandatory_locked(inode);
1587 return 0;
1590 extern int rw_verify_area(int, struct file *, loff_t *, size_t);
1592 static inline int locks_verify_truncate(struct inode *inode,
1593 struct file *filp,
1594 loff_t size)
1596 if (inode->i_flock && mandatory_lock(inode))
1597 return locks_mandatory_area(
1598 FLOCK_VERIFY_WRITE, inode, filp,
1599 size < inode->i_size ? size : inode->i_size,
1600 (size < inode->i_size ? inode->i_size - size
1601 : size - inode->i_size)
1603 return 0;
1606 static inline int break_lease(struct inode *inode, unsigned int mode)
1608 if (inode->i_flock)
1609 return __break_lease(inode, mode);
1610 return 0;
1613 /* fs/open.c */
1615 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
1616 struct file *filp);
1617 extern long do_sys_open(int dfd, const char __user *filename, int flags,
1618 int mode);
1619 extern struct file *filp_open(const char *, int, int);
1620 extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
1621 extern int filp_close(struct file *, fl_owner_t id);
1622 extern char * getname(const char __user *);
1624 /* fs/dcache.c */
1625 extern void __init vfs_caches_init_early(void);
1626 extern void __init vfs_caches_init(unsigned long);
1628 extern struct kmem_cache *names_cachep;
1630 #define __getname() kmem_cache_alloc(names_cachep, GFP_KERNEL)
1631 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
1632 #ifndef CONFIG_AUDITSYSCALL
1633 #define putname(name) __putname(name)
1634 #else
1635 extern void putname(const char *name);
1636 #endif
1638 #ifdef CONFIG_BLOCK
1639 extern int register_blkdev(unsigned int, const char *);
1640 extern void unregister_blkdev(unsigned int, const char *);
1641 extern struct block_device *bdget(dev_t);
1642 extern void bd_set_size(struct block_device *, loff_t size);
1643 extern void bd_forget(struct inode *inode);
1644 extern void bdput(struct block_device *);
1645 extern struct block_device *open_by_devnum(dev_t, unsigned);
1646 #else
1647 static inline void bd_forget(struct inode *inode) {}
1648 #endif
1649 extern const struct file_operations def_blk_fops;
1650 extern const struct file_operations def_chr_fops;
1651 extern const struct file_operations bad_sock_fops;
1652 extern const struct file_operations def_fifo_fops;
1653 #ifdef CONFIG_BLOCK
1654 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
1655 extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
1656 extern int blkdev_driver_ioctl(struct inode *inode, struct file *file,
1657 struct gendisk *disk, unsigned cmd,
1658 unsigned long arg);
1659 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
1660 extern int blkdev_get(struct block_device *, mode_t, unsigned);
1661 extern int blkdev_put(struct block_device *);
1662 extern int bd_claim(struct block_device *, void *);
1663 extern void bd_release(struct block_device *);
1664 #ifdef CONFIG_SYSFS
1665 extern int bd_claim_by_disk(struct block_device *, void *, struct gendisk *);
1666 extern void bd_release_from_disk(struct block_device *, struct gendisk *);
1667 #else
1668 #define bd_claim_by_disk(bdev, holder, disk) bd_claim(bdev, holder)
1669 #define bd_release_from_disk(bdev, disk) bd_release(bdev)
1670 #endif
1671 #endif
1673 /* fs/char_dev.c */
1674 #define CHRDEV_MAJOR_HASH_SIZE 255
1675 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
1676 extern int register_chrdev_region(dev_t, unsigned, const char *);
1677 extern int register_chrdev(unsigned int, const char *,
1678 const struct file_operations *);
1679 extern void unregister_chrdev(unsigned int, const char *);
1680 extern void unregister_chrdev_region(dev_t, unsigned);
1681 extern void chrdev_show(struct seq_file *,off_t);
1683 /* fs/block_dev.c */
1684 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
1686 #ifdef CONFIG_BLOCK
1687 #define BLKDEV_MAJOR_HASH_SIZE 255
1688 extern const char *__bdevname(dev_t, char *buffer);
1689 extern const char *bdevname(struct block_device *bdev, char *buffer);
1690 extern struct block_device *lookup_bdev(const char *);
1691 extern struct block_device *open_bdev_excl(const char *, int, void *);
1692 extern void close_bdev_excl(struct block_device *);
1693 extern void blkdev_show(struct seq_file *,off_t);
1694 #else
1695 #define BLKDEV_MAJOR_HASH_SIZE 0
1696 #endif
1698 extern void init_special_inode(struct inode *, umode_t, dev_t);
1700 /* Invalid inode operations -- fs/bad_inode.c */
1701 extern void make_bad_inode(struct inode *);
1702 extern int is_bad_inode(struct inode *);
1704 extern const struct file_operations read_pipefifo_fops;
1705 extern const struct file_operations write_pipefifo_fops;
1706 extern const struct file_operations rdwr_pipefifo_fops;
1708 extern int fs_may_remount_ro(struct super_block *);
1710 #ifdef CONFIG_BLOCK
1712 * return READ, READA, or WRITE
1714 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
1717 * return data direction, READ or WRITE
1719 #define bio_data_dir(bio) ((bio)->bi_rw & 1)
1721 extern int check_disk_change(struct block_device *);
1722 extern int __invalidate_device(struct block_device *);
1723 extern int invalidate_partition(struct gendisk *, int);
1724 #endif
1725 extern int invalidate_inodes(struct super_block *);
1726 unsigned long __invalidate_mapping_pages(struct address_space *mapping,
1727 pgoff_t start, pgoff_t end,
1728 bool be_atomic);
1729 unsigned long invalidate_mapping_pages(struct address_space *mapping,
1730 pgoff_t start, pgoff_t end);
1732 static inline unsigned long __deprecated
1733 invalidate_inode_pages(struct address_space *mapping)
1735 return invalidate_mapping_pages(mapping, 0, ~0UL);
1738 static inline void invalidate_remote_inode(struct inode *inode)
1740 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1741 S_ISLNK(inode->i_mode))
1742 invalidate_mapping_pages(inode->i_mapping, 0, -1);
1744 extern int invalidate_inode_pages2(struct address_space *mapping);
1745 extern int invalidate_inode_pages2_range(struct address_space *mapping,
1746 pgoff_t start, pgoff_t end);
1747 extern void generic_sync_sb_inodes(struct super_block *sb,
1748 struct writeback_control *wbc);
1749 extern int write_inode_now(struct inode *, int);
1750 extern int filemap_fdatawrite(struct address_space *);
1751 extern int filemap_flush(struct address_space *);
1752 extern int filemap_fdatawait(struct address_space *);
1753 extern int filemap_write_and_wait(struct address_space *mapping);
1754 extern int filemap_write_and_wait_range(struct address_space *mapping,
1755 loff_t lstart, loff_t lend);
1756 extern int wait_on_page_writeback_range(struct address_space *mapping,
1757 pgoff_t start, pgoff_t end);
1758 extern int __filemap_fdatawrite_range(struct address_space *mapping,
1759 loff_t start, loff_t end, int sync_mode);
1760 extern int filemap_fdatawrite_range(struct address_space *mapping,
1761 loff_t start, loff_t end);
1763 extern long do_fsync(struct file *file, int datasync);
1764 extern void sync_supers(void);
1765 extern void sync_filesystems(int wait);
1766 extern void __fsync_super(struct super_block *sb);
1767 extern void emergency_sync(void);
1768 extern void emergency_remount(void);
1769 extern int do_remount_sb(struct super_block *sb, int flags,
1770 void *data, int force);
1771 #ifdef CONFIG_BLOCK
1772 extern sector_t bmap(struct inode *, sector_t);
1773 #endif
1774 extern int notify_change(struct dentry *, struct iattr *);
1775 extern int inode_permission(struct inode *, int);
1776 extern int generic_permission(struct inode *, int,
1777 int (*check_acl)(struct inode *, int));
1779 extern int get_write_access(struct inode *);
1780 extern int deny_write_access(struct file *);
1781 static inline void put_write_access(struct inode * inode)
1783 atomic_dec(&inode->i_writecount);
1785 static inline void allow_write_access(struct file *file)
1787 if (file)
1788 atomic_inc(&file->f_path.dentry->d_inode->i_writecount);
1790 extern int do_pipe(int *);
1791 extern int do_pipe_flags(int *, int);
1792 extern struct file *create_read_pipe(struct file *f, int flags);
1793 extern struct file *create_write_pipe(int flags);
1794 extern void free_write_pipe(struct file *);
1796 extern struct file *do_filp_open(int dfd, const char *pathname,
1797 int open_flag, int mode);
1798 extern int may_open(struct nameidata *, int, int);
1800 extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
1801 extern struct file * open_exec(const char *);
1803 /* fs/dcache.c -- generic fs support functions */
1804 extern int is_subdir(struct dentry *, struct dentry *);
1805 extern ino_t find_inode_number(struct dentry *, struct qstr *);
1807 #include <linux/err.h>
1809 /* needed for stackable file system support */
1810 extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
1812 extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
1814 extern void inode_init_once(struct inode *);
1815 extern void iput(struct inode *);
1816 extern struct inode * igrab(struct inode *);
1817 extern ino_t iunique(struct super_block *, ino_t);
1818 extern int inode_needs_sync(struct inode *inode);
1819 extern void generic_delete_inode(struct inode *inode);
1820 extern void generic_drop_inode(struct inode *inode);
1822 extern struct inode *ilookup5_nowait(struct super_block *sb,
1823 unsigned long hashval, int (*test)(struct inode *, void *),
1824 void *data);
1825 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
1826 int (*test)(struct inode *, void *), void *data);
1827 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
1829 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
1830 extern struct inode * iget_locked(struct super_block *, unsigned long);
1831 extern void unlock_new_inode(struct inode *);
1833 extern void __iget(struct inode * inode);
1834 extern void iget_failed(struct inode *);
1835 extern void clear_inode(struct inode *);
1836 extern void destroy_inode(struct inode *);
1837 extern struct inode *new_inode(struct super_block *);
1838 extern int should_remove_suid(struct dentry *);
1839 extern int file_remove_suid(struct file *);
1841 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
1842 extern void remove_inode_hash(struct inode *);
1843 static inline void insert_inode_hash(struct inode *inode) {
1844 __insert_inode_hash(inode, inode->i_ino);
1847 extern struct file * get_empty_filp(void);
1848 extern void file_move(struct file *f, struct list_head *list);
1849 extern void file_kill(struct file *f);
1850 #ifdef CONFIG_BLOCK
1851 struct bio;
1852 extern void submit_bio(int, struct bio *);
1853 extern int bdev_read_only(struct block_device *);
1854 #endif
1855 extern int set_blocksize(struct block_device *, int);
1856 extern int sb_set_blocksize(struct super_block *, int);
1857 extern int sb_min_blocksize(struct super_block *, int);
1858 extern int sb_has_dirty_inodes(struct super_block *);
1860 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
1861 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
1862 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1863 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
1864 extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
1865 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
1866 extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
1867 unsigned long, loff_t);
1868 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
1869 unsigned long *, loff_t, loff_t *, size_t, size_t);
1870 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
1871 unsigned long, loff_t, loff_t *, size_t, ssize_t);
1872 extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
1873 extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
1874 extern int generic_segment_checks(const struct iovec *iov,
1875 unsigned long *nr_segs, size_t *count, int access_flags);
1877 /* fs/splice.c */
1878 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
1879 struct pipe_inode_info *, size_t, unsigned int);
1880 extern ssize_t generic_file_splice_write(struct pipe_inode_info *,
1881 struct file *, loff_t *, size_t, unsigned int);
1882 extern ssize_t generic_file_splice_write_nolock(struct pipe_inode_info *,
1883 struct file *, loff_t *, size_t, unsigned int);
1884 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
1885 struct file *out, loff_t *, size_t len, unsigned int flags);
1886 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
1887 size_t len, unsigned int flags);
1889 extern void
1890 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
1891 extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
1892 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
1893 extern loff_t generic_file_llseek_unlocked(struct file *file, loff_t offset,
1894 int origin);
1895 extern int generic_file_open(struct inode * inode, struct file * filp);
1896 extern int nonseekable_open(struct inode * inode, struct file * filp);
1898 #ifdef CONFIG_FS_XIP
1899 extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
1900 loff_t *ppos);
1901 extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
1902 extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
1903 size_t len, loff_t *ppos);
1904 extern int xip_truncate_page(struct address_space *mapping, loff_t from);
1905 #else
1906 static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
1908 return 0;
1910 #endif
1912 #ifdef CONFIG_BLOCK
1913 ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
1914 struct block_device *bdev, const struct iovec *iov, loff_t offset,
1915 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
1916 int lock_type);
1918 enum {
1919 DIO_LOCKING = 1, /* need locking between buffered and direct access */
1920 DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */
1921 DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */
1924 static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
1925 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1926 loff_t offset, unsigned long nr_segs, get_block_t get_block,
1927 dio_iodone_t end_io)
1929 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1930 nr_segs, get_block, end_io, DIO_LOCKING);
1933 static inline ssize_t blockdev_direct_IO_no_locking(int rw, struct kiocb *iocb,
1934 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1935 loff_t offset, unsigned long nr_segs, get_block_t get_block,
1936 dio_iodone_t end_io)
1938 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1939 nr_segs, get_block, end_io, DIO_NO_LOCKING);
1942 static inline ssize_t blockdev_direct_IO_own_locking(int rw, struct kiocb *iocb,
1943 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1944 loff_t offset, unsigned long nr_segs, get_block_t get_block,
1945 dio_iodone_t end_io)
1947 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1948 nr_segs, get_block, end_io, DIO_OWN_LOCKING);
1950 #endif
1952 extern const struct file_operations generic_ro_fops;
1954 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
1956 extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
1957 extern int vfs_follow_link(struct nameidata *, const char *);
1958 extern int page_readlink(struct dentry *, char __user *, int);
1959 extern void *page_follow_link_light(struct dentry *, struct nameidata *);
1960 extern void page_put_link(struct dentry *, struct nameidata *, void *);
1961 extern int __page_symlink(struct inode *inode, const char *symname, int len,
1962 gfp_t gfp_mask);
1963 extern int page_symlink(struct inode *inode, const char *symname, int len);
1964 extern const struct inode_operations page_symlink_inode_operations;
1965 extern int generic_readlink(struct dentry *, char __user *, int);
1966 extern void generic_fillattr(struct inode *, struct kstat *);
1967 extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1968 void inode_add_bytes(struct inode *inode, loff_t bytes);
1969 void inode_sub_bytes(struct inode *inode, loff_t bytes);
1970 loff_t inode_get_bytes(struct inode *inode);
1971 void inode_set_bytes(struct inode *inode, loff_t bytes);
1973 extern int vfs_readdir(struct file *, filldir_t, void *);
1975 extern int vfs_stat(char __user *, struct kstat *);
1976 extern int vfs_lstat(char __user *, struct kstat *);
1977 extern int vfs_stat_fd(int dfd, char __user *, struct kstat *);
1978 extern int vfs_lstat_fd(int dfd, char __user *, struct kstat *);
1979 extern int vfs_fstat(unsigned int, struct kstat *);
1981 extern int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
1982 unsigned long arg);
1984 extern void get_filesystem(struct file_system_type *fs);
1985 extern void put_filesystem(struct file_system_type *fs);
1986 extern struct file_system_type *get_fs_type(const char *name);
1987 extern struct super_block *get_super(struct block_device *);
1988 extern struct super_block *user_get_super(dev_t);
1989 extern void drop_super(struct super_block *sb);
1991 extern int dcache_dir_open(struct inode *, struct file *);
1992 extern int dcache_dir_close(struct inode *, struct file *);
1993 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
1994 extern int dcache_readdir(struct file *, void *, filldir_t);
1995 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1996 extern int simple_statfs(struct dentry *, struct kstatfs *);
1997 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
1998 extern int simple_unlink(struct inode *, struct dentry *);
1999 extern int simple_rmdir(struct inode *, struct dentry *);
2000 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
2001 extern int simple_sync_file(struct file *, struct dentry *, int);
2002 extern int simple_empty(struct dentry *);
2003 extern int simple_readpage(struct file *file, struct page *page);
2004 extern int simple_prepare_write(struct file *file, struct page *page,
2005 unsigned offset, unsigned to);
2006 extern int simple_write_begin(struct file *file, struct address_space *mapping,
2007 loff_t pos, unsigned len, unsigned flags,
2008 struct page **pagep, void **fsdata);
2009 extern int simple_write_end(struct file *file, struct address_space *mapping,
2010 loff_t pos, unsigned len, unsigned copied,
2011 struct page *page, void *fsdata);
2013 extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
2014 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
2015 extern const struct file_operations simple_dir_operations;
2016 extern const struct inode_operations simple_dir_inode_operations;
2017 struct tree_descr { char *name; const struct file_operations *ops; int mode; };
2018 struct dentry *d_alloc_name(struct dentry *, const char *);
2019 extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
2020 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
2021 extern void simple_release_fs(struct vfsmount **mount, int *count);
2023 extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
2024 loff_t *ppos, const void *from, size_t available);
2026 #ifdef CONFIG_MIGRATION
2027 extern int buffer_migrate_page(struct address_space *,
2028 struct page *, struct page *);
2029 #else
2030 #define buffer_migrate_page NULL
2031 #endif
2033 extern int inode_change_ok(struct inode *, struct iattr *);
2034 extern int __must_check inode_setattr(struct inode *, struct iattr *);
2036 extern void file_update_time(struct file *file);
2038 extern int generic_show_options(struct seq_file *m, struct vfsmount *mnt);
2039 extern void save_mount_options(struct super_block *sb, char *options);
2041 static inline ino_t parent_ino(struct dentry *dentry)
2043 ino_t res;
2045 spin_lock(&dentry->d_lock);
2046 res = dentry->d_parent->d_inode->i_ino;
2047 spin_unlock(&dentry->d_lock);
2048 return res;
2051 /* Transaction based IO helpers */
2054 * An argresp is stored in an allocated page and holds the
2055 * size of the argument or response, along with its content
2057 struct simple_transaction_argresp {
2058 ssize_t size;
2059 char data[0];
2062 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
2064 char *simple_transaction_get(struct file *file, const char __user *buf,
2065 size_t size);
2066 ssize_t simple_transaction_read(struct file *file, char __user *buf,
2067 size_t size, loff_t *pos);
2068 int simple_transaction_release(struct inode *inode, struct file *file);
2070 static inline void simple_transaction_set(struct file *file, size_t n)
2072 struct simple_transaction_argresp *ar = file->private_data;
2074 BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
2077 * The barrier ensures that ar->size will really remain zero until
2078 * ar->data is ready for reading.
2080 smp_mb();
2081 ar->size = n;
2085 * simple attribute files
2087 * These attributes behave similar to those in sysfs:
2089 * Writing to an attribute immediately sets a value, an open file can be
2090 * written to multiple times.
2092 * Reading from an attribute creates a buffer from the value that might get
2093 * read with multiple read calls. When the attribute has been read
2094 * completely, no further read calls are possible until the file is opened
2095 * again.
2097 * All attributes contain a text representation of a numeric value
2098 * that are accessed with the get() and set() functions.
2100 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
2101 static int __fops ## _open(struct inode *inode, struct file *file) \
2103 __simple_attr_check_format(__fmt, 0ull); \
2104 return simple_attr_open(inode, file, __get, __set, __fmt); \
2106 static struct file_operations __fops = { \
2107 .owner = THIS_MODULE, \
2108 .open = __fops ## _open, \
2109 .release = simple_attr_release, \
2110 .read = simple_attr_read, \
2111 .write = simple_attr_write, \
2114 static inline void __attribute__((format(printf, 1, 2)))
2115 __simple_attr_check_format(const char *fmt, ...)
2117 /* don't do anything, just let the compiler check the arguments; */
2120 int simple_attr_open(struct inode *inode, struct file *file,
2121 int (*get)(void *, u64 *), int (*set)(void *, u64),
2122 const char *fmt);
2123 int simple_attr_release(struct inode *inode, struct file *file);
2124 ssize_t simple_attr_read(struct file *file, char __user *buf,
2125 size_t len, loff_t *ppos);
2126 ssize_t simple_attr_write(struct file *file, const char __user *buf,
2127 size_t len, loff_t *ppos);
2130 #ifdef CONFIG_SECURITY
2131 static inline char *alloc_secdata(void)
2133 return (char *)get_zeroed_page(GFP_KERNEL);
2136 static inline void free_secdata(void *secdata)
2138 free_page((unsigned long)secdata);
2140 #else
2141 static inline char *alloc_secdata(void)
2143 return (char *)1;
2146 static inline void free_secdata(void *secdata)
2148 #endif /* CONFIG_SECURITY */
2150 struct ctl_table;
2151 int proc_nr_files(struct ctl_table *table, int write, struct file *filp,
2152 void __user *buffer, size_t *lenp, loff_t *ppos);
2154 int get_filesystem_list(char * buf);
2156 #endif /* __KERNEL__ */
2157 #endif /* _LINUX_FS_H */