5 * This file has definitions for some important file table
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: */
24 #define NR_OPEN (1024*1024) /* Absolute upper limit on fd num */
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 */
34 /* And dynamically-tunable limits and defaults: */
35 struct files_stat_struct {
36 int nr_files; /* read only */
37 int nr_free_files; /* read only */
38 int max_files; /* tunable */
40 extern struct files_stat_struct files_stat;
41 extern int get_max_files(void);
43 struct inodes_stat_t {
48 extern struct inodes_stat_t inodes_stat;
50 extern int leases_enable, lease_break_time;
53 extern int dir_notify_enable;
56 #define NR_FILE 8192 /* this can well be larger on a larger system */
66 /* Internal kernel extensions */
69 #define FMODE_PWRITE FMODE_PREAD /* These go hand in hand */
71 /* File is being opened for execution. Primary users of this flag are
72 distributed filesystems that can use it to achieve correct ETXTBUSY
73 behavior for cross-node execution/opening_for_writing of files */
80 #define READA 2 /* read-ahead - don't block if no resources */
81 #define SWRITE 3 /* for ll_rw_block() - wait for buffer lock */
82 #define READ_SYNC (READ | (1 << BIO_RW_SYNC))
83 #define READ_META (READ | (1 << BIO_RW_META))
84 #define WRITE_SYNC (WRITE | (1 << BIO_RW_SYNC))
85 #define WRITE_BARRIER ((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
91 /* public flags for file_system_type */
92 #define FS_REQUIRES_DEV 1
93 #define FS_BINARY_MOUNTDATA 2
94 #define FS_REVAL_DOT 16384 /* Check the paths ".", ".." for staleness */
95 #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move()
96 * during rename() internally.
100 * These are the fs-independent mount-flags: up to 32 flags are supported
102 #define MS_RDONLY 1 /* Mount read-only */
103 #define MS_NOSUID 2 /* Ignore suid and sgid bits */
104 #define MS_NODEV 4 /* Disallow access to device special files */
105 #define MS_NOEXEC 8 /* Disallow program execution */
106 #define MS_SYNCHRONOUS 16 /* Writes are synced at once */
107 #define MS_REMOUNT 32 /* Alter flags of a mounted FS */
108 #define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
109 #define MS_DIRSYNC 128 /* Directory modifications are synchronous */
110 #define MS_NOATIME 1024 /* Do not update access times. */
111 #define MS_NODIRATIME 2048 /* Do not update directory access times */
115 #define MS_VERBOSE 32768 /* War is peace. Verbosity is silence.
116 MS_VERBOSE is deprecated. */
117 #define MS_SILENT 32768
118 #define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
119 #define MS_UNBINDABLE (1<<17) /* change to unbindable */
120 #define MS_PRIVATE (1<<18) /* change to private */
121 #define MS_SLAVE (1<<19) /* change to slave */
122 #define MS_SHARED (1<<20) /* change to shared */
123 #define MS_ACTIVE (1<<30)
124 #define MS_NOUSER (1<<31)
127 * Superblock flags that can be altered by MS_REMOUNT
129 #define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK)
132 * Old magic mount flag and mask
134 #define MS_MGC_VAL 0xC0ED0000
135 #define MS_MGC_MSK 0xffff0000
137 /* Inode flags - they have nothing to superblock flags now */
139 #define S_SYNC 1 /* Writes are synced at once */
140 #define S_NOATIME 2 /* Do not update access times */
141 #define S_APPEND 4 /* Append-only file */
142 #define S_IMMUTABLE 8 /* Immutable file */
143 #define S_DEAD 16 /* removed, but still open directory */
144 #define S_NOQUOTA 32 /* Inode is not counted to quota */
145 #define S_DIRSYNC 64 /* Directory modifications are synchronous */
146 #define S_NOCMTIME 128 /* Do not update file c/mtime */
147 #define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */
148 #define S_PRIVATE 512 /* Inode is fs-internal */
151 * Note that nosuid etc flags are inode-specific: setting some file-system
152 * flags just means all the inodes inherit those flags by default. It might be
153 * possible to override it selectively if you really wanted to with some
154 * ioctl() that is not currently implemented.
156 * Exception: MS_RDONLY is always applied to the entire file system.
158 * Unfortunately, it is possible to change a filesystems flags with it mounted
159 * with files in use. This means that all of the inodes will not have their
160 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
161 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
163 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
165 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
166 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || \
167 ((inode)->i_flags & S_SYNC))
168 #define IS_DIRSYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
169 ((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
170 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
172 #define IS_NOQUOTA(inode) ((inode)->i_flags & S_NOQUOTA)
173 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
174 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
175 #define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)
177 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
178 #define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
179 #define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
180 #define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)
182 /* the read-only stuff doesn't really belong here, but any other place is
183 probably as bad and I don't want to create yet another include file. */
185 #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
186 #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
187 #define BLKRRPART _IO(0x12,95) /* re-read partition table */
188 #define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
189 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
190 #define BLKRASET _IO(0x12,98) /* set read ahead for block device */
191 #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
192 #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
193 #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
194 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
195 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
196 #define BLKSSZGET _IO(0x12,104)/* get block device sector size */
198 #define BLKPG _IO(0x12,105)/* See blkpg.h */
200 /* Some people are morons. Do not use sizeof! */
202 #define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
203 #define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
204 /* This was here just to show that the number is taken -
205 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
207 /* A jump here: 108-111 have been used for various private purposes. */
208 #define BLKBSZGET _IOR(0x12,112,size_t)
209 #define BLKBSZSET _IOW(0x12,113,size_t)
210 #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
211 #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
212 #define BLKTRACESTART _IO(0x12,116)
213 #define BLKTRACESTOP _IO(0x12,117)
214 #define BLKTRACETEARDOWN _IO(0x12,118)
216 #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
217 #define FIBMAP _IO(0x00,1) /* bmap access */
218 #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
220 #define FS_IOC_GETFLAGS _IOR('f', 1, long)
221 #define FS_IOC_SETFLAGS _IOW('f', 2, long)
222 #define FS_IOC_GETVERSION _IOR('v', 1, long)
223 #define FS_IOC_SETVERSION _IOW('v', 2, long)
224 #define FS_IOC32_GETFLAGS _IOR('f', 1, int)
225 #define FS_IOC32_SETFLAGS _IOW('f', 2, int)
226 #define FS_IOC32_GETVERSION _IOR('v', 1, int)
227 #define FS_IOC32_SETVERSION _IOW('v', 2, int)
230 * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
232 #define FS_SECRM_FL 0x00000001 /* Secure deletion */
233 #define FS_UNRM_FL 0x00000002 /* Undelete */
234 #define FS_COMPR_FL 0x00000004 /* Compress file */
235 #define FS_SYNC_FL 0x00000008 /* Synchronous updates */
236 #define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */
237 #define FS_APPEND_FL 0x00000020 /* writes to file may only append */
238 #define FS_NODUMP_FL 0x00000040 /* do not dump file */
239 #define FS_NOATIME_FL 0x00000080 /* do not update atime */
240 /* Reserved for compression usage... */
241 #define FS_DIRTY_FL 0x00000100
242 #define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
243 #define FS_NOCOMP_FL 0x00000400 /* Don't compress */
244 #define FS_ECOMPR_FL 0x00000800 /* Compression error */
245 /* End compression flags --- maybe not all used */
246 #define FS_BTREE_FL 0x00001000 /* btree format dir */
247 #define FS_INDEX_FL 0x00001000 /* hash-indexed directory */
248 #define FS_IMAGIC_FL 0x00002000 /* AFS directory */
249 #define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
250 #define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */
251 #define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
252 #define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
253 #define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
255 #define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
256 #define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
259 #define SYNC_FILE_RANGE_WAIT_BEFORE 1
260 #define SYNC_FILE_RANGE_WRITE 2
261 #define SYNC_FILE_RANGE_WAIT_AFTER 4
265 #include <linux/linkage.h>
266 #include <linux/wait.h>
267 #include <linux/types.h>
268 #include <linux/kdev_t.h>
269 #include <linux/dcache.h>
270 #include <linux/stat.h>
271 #include <linux/cache.h>
272 #include <linux/kobject.h>
273 #include <linux/list.h>
274 #include <linux/radix-tree.h>
275 #include <linux/prio_tree.h>
276 #include <linux/init.h>
277 #include <linux/sched.h>
278 #include <linux/mutex.h>
280 #include <asm/atomic.h>
281 #include <asm/semaphore.h>
282 #include <asm/byteorder.h>
288 struct pipe_inode_info;
289 struct poll_table_struct;
291 struct vm_area_struct;
294 extern void __init inode_init(unsigned long);
295 extern void __init inode_init_early(void);
296 extern void __init mnt_init(unsigned long);
297 extern void __init files_init(unsigned long);
300 typedef int (get_block_t)(struct inode *inode, sector_t iblock,
301 struct buffer_head *bh_result, int create);
302 typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
303 ssize_t bytes, void *private);
306 * Attribute flags. These should be or-ed together to figure out what
313 #define ATTR_ATIME 16
314 #define ATTR_MTIME 32
315 #define ATTR_CTIME 64
316 #define ATTR_ATIME_SET 128
317 #define ATTR_MTIME_SET 256
318 #define ATTR_FORCE 512 /* Not a change, but a change it */
319 #define ATTR_ATTR_FLAG 1024
320 #define ATTR_KILL_SUID 2048
321 #define ATTR_KILL_SGID 4096
322 #define ATTR_FILE 8192
325 * This is the Inode Attributes structure, used for notify_change(). It
326 * uses the above definitions as flags, to know which values have changed.
327 * Also, in this manner, a Filesystem can look at only the values it cares
328 * about. Basically, these are the attributes that the VFS layer can
329 * request to change from the FS layer.
331 * Derek Atkins <warlord@MIT.EDU> 94-10-20
334 unsigned int ia_valid;
339 struct timespec ia_atime;
340 struct timespec ia_mtime;
341 struct timespec ia_ctime;
344 * Not an attribute, but an auxilary info for filesystems wanting to
345 * implement an ftruncate() like method. NOTE: filesystem should
346 * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
348 struct file *ia_file;
352 * Includes for diskquotas.
354 #include <linux/quota.h>
357 * enum positive_aop_returns - aop return codes with specific semantics
359 * @AOP_WRITEPAGE_ACTIVATE: Informs the caller that page writeback has
360 * completed, that the page is still locked, and
361 * should be considered active. The VM uses this hint
362 * to return the page to the active list -- it won't
363 * be a candidate for writeback again in the near
364 * future. Other callers must be careful to unlock
365 * the page if they get this return. Returned by
368 * @AOP_TRUNCATED_PAGE: The AOP method that was handed a locked page has
369 * unlocked it and the page might have been truncated.
370 * The caller should back up to acquiring a new page and
371 * trying again. The aop will be taking reasonable
372 * precautions not to livelock. If the caller held a page
373 * reference, it should drop it before retrying. Returned
374 * by readpage(), prepare_write(), and commit_write().
376 * address_space_operation functions return these large constants to indicate
377 * special semantics to the caller. These are much larger than the bytes in a
378 * page to allow for functions that return the number of bytes operated on in a
382 enum positive_aop_returns {
383 AOP_WRITEPAGE_ACTIVATE = 0x80000,
384 AOP_TRUNCATED_PAGE = 0x80001,
388 * oh the beauties of C type declarations.
391 struct address_space;
392 struct writeback_control;
394 struct address_space_operations {
395 int (*writepage)(struct page *page, struct writeback_control *wbc);
396 int (*readpage)(struct file *, struct page *);
397 void (*sync_page)(struct page *);
399 /* Write back some dirty pages from this mapping. */
400 int (*writepages)(struct address_space *, struct writeback_control *);
402 /* Set a page dirty. Return true if this dirtied it */
403 int (*set_page_dirty)(struct page *page);
405 int (*readpages)(struct file *filp, struct address_space *mapping,
406 struct list_head *pages, unsigned nr_pages);
409 * ext3 requires that a successful prepare_write() call be followed
410 * by a commit_write() call - they must be balanced
412 int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
413 int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
414 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
415 sector_t (*bmap)(struct address_space *, sector_t);
416 void (*invalidatepage) (struct page *, unsigned long);
417 int (*releasepage) (struct page *, gfp_t);
418 ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
419 loff_t offset, unsigned long nr_segs);
420 struct page* (*get_xip_page)(struct address_space *, sector_t,
422 /* migrate the contents of a page to the specified target */
423 int (*migratepage) (struct address_space *,
424 struct page *, struct page *);
427 struct backing_dev_info;
428 struct address_space {
429 struct inode *host; /* owner: inode, block_device */
430 struct radix_tree_root page_tree; /* radix tree of all pages */
431 rwlock_t tree_lock; /* and rwlock protecting it */
432 unsigned int i_mmap_writable;/* count VM_SHARED mappings */
433 struct prio_tree_root i_mmap; /* tree of private and shared mappings */
434 struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */
435 spinlock_t i_mmap_lock; /* protect tree, count, list */
436 unsigned int truncate_count; /* Cover race condition with truncate */
437 unsigned long nrpages; /* number of total pages */
438 pgoff_t writeback_index;/* writeback starts here */
439 const struct address_space_operations *a_ops; /* methods */
440 unsigned long flags; /* error bits/gfp mask */
441 struct backing_dev_info *backing_dev_info; /* device readahead, etc */
442 spinlock_t private_lock; /* for use by the address_space */
443 struct list_head private_list; /* ditto */
444 struct address_space *assoc_mapping; /* ditto */
445 } __attribute__((aligned(sizeof(long))));
447 * On most architectures that alignment is already the case; but
448 * must be enforced here for CRIS, to let the least signficant bit
449 * of struct page's "mapping" pointer be used for PAGE_MAPPING_ANON.
452 struct block_device {
453 dev_t bd_dev; /* not a kdev_t - it's a search key */
454 struct inode * bd_inode; /* will die */
456 struct mutex bd_mutex; /* open/close mutex */
457 struct mutex bd_mount_mutex; /* mount mutex */
458 struct list_head bd_inodes;
462 struct list_head bd_holder_list;
464 struct block_device * bd_contains;
465 unsigned bd_block_size;
466 struct hd_struct * bd_part;
467 /* number of times partitions within this device have been opened. */
468 unsigned bd_part_count;
470 struct gendisk * bd_disk;
471 struct list_head bd_list;
472 struct backing_dev_info *bd_inode_backing_dev_info;
474 * Private data. You must have bd_claim'ed the block_device
475 * to use this. NOTE: bd_claim allows an owner to claim
476 * the same device multiple times, the owner must take special
477 * care to not mess up bd_private for that case.
479 unsigned long bd_private;
483 * bdev->bd_mutex nesting subclasses for the lock validator:
489 enum bdev_bd_mutex_lock_class
498 * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
501 #define PAGECACHE_TAG_DIRTY 0
502 #define PAGECACHE_TAG_WRITEBACK 1
504 int mapping_tagged(struct address_space *mapping, int tag);
507 * Might pages of this file be mapped into userspace?
509 static inline int mapping_mapped(struct address_space *mapping)
511 return !prio_tree_empty(&mapping->i_mmap) ||
512 !list_empty(&mapping->i_mmap_nonlinear);
516 * Might pages of this file have been modified in userspace?
517 * Note that i_mmap_writable counts all VM_SHARED vmas: do_mmap_pgoff
518 * marks vma as VM_SHARED if it is shared, and the file was opened for
519 * writing i.e. vma may be mprotected writable even if now readonly.
521 static inline int mapping_writably_mapped(struct address_space *mapping)
523 return mapping->i_mmap_writable != 0;
527 * Use sequence counter to get consistent i_size on 32-bit processors.
529 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
530 #include <linux/seqlock.h>
531 #define __NEED_I_SIZE_ORDERED
532 #define i_size_ordered_init(inode) seqcount_init(&inode->i_size_seqcount)
534 #define i_size_ordered_init(inode) do { } while (0)
538 struct hlist_node i_hash;
539 struct list_head i_list;
540 struct list_head i_sb_list;
541 struct list_head i_dentry;
545 unsigned int i_nlink;
550 struct timespec i_atime;
551 struct timespec i_mtime;
552 struct timespec i_ctime;
553 unsigned int i_blkbits;
554 unsigned long i_version;
556 unsigned short i_bytes;
557 spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
558 struct mutex i_mutex;
559 struct rw_semaphore i_alloc_sem;
560 struct inode_operations *i_op;
561 const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
562 struct super_block *i_sb;
563 struct file_lock *i_flock;
564 struct address_space *i_mapping;
565 struct address_space i_data;
567 struct dquot *i_dquot[MAXQUOTAS];
569 struct list_head i_devices;
571 struct pipe_inode_info *i_pipe;
572 struct block_device *i_bdev;
579 #ifdef CONFIG_DNOTIFY
580 unsigned long i_dnotify_mask; /* Directory notify events */
581 struct dnotify_struct *i_dnotify; /* for directory notifications */
584 #ifdef CONFIG_INOTIFY
585 struct list_head inotify_watches; /* watches on this inode */
586 struct mutex inotify_mutex; /* protects the watches list */
589 unsigned long i_state;
590 unsigned long dirtied_when; /* jiffies of first dirtying */
592 unsigned int i_flags;
594 atomic_t i_writecount;
595 #ifdef CONFIG_SECURITY
598 void *i_private; /* fs or device private pointer */
599 #ifdef __NEED_I_SIZE_ORDERED
600 seqcount_t i_size_seqcount;
605 * inode->i_mutex nesting subclasses for the lock validator:
607 * 0: the object of the current VFS operation
612 * The locking order between these classes is
613 * parent -> child -> normal -> xattr -> quota
615 enum inode_i_mutex_lock_class
625 * NOTE: in a 32bit arch with a preemptable kernel and
626 * an UP compile the i_size_read/write must be atomic
627 * with respect to the local cpu (unlike with preempt disabled),
628 * but they don't need to be atomic with respect to other cpus like in
629 * true SMP (so they need either to either locally disable irq around
630 * the read or for example on x86 they can be still implemented as a
631 * cmpxchg8b without the need of the lock prefix). For SMP compiles
632 * and 64bit archs it makes no difference if preempt is enabled or not.
634 static inline loff_t i_size_read(struct inode *inode)
636 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
641 seq = read_seqcount_begin(&inode->i_size_seqcount);
642 i_size = inode->i_size;
643 } while (read_seqcount_retry(&inode->i_size_seqcount, seq));
645 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
649 i_size = inode->i_size;
653 return inode->i_size;
658 static inline void i_size_write(struct inode *inode, loff_t i_size)
660 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
661 write_seqcount_begin(&inode->i_size_seqcount);
662 inode->i_size = i_size;
663 write_seqcount_end(&inode->i_size_seqcount);
664 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
666 inode->i_size = i_size;
669 inode->i_size = i_size;
673 static inline unsigned iminor(struct inode *inode)
675 return MINOR(inode->i_rdev);
678 static inline unsigned imajor(struct inode *inode)
680 return MAJOR(inode->i_rdev);
683 extern struct block_device *I_BDEV(struct inode *inode);
686 rwlock_t lock; /* protects pid, uid, euid fields */
687 int pid; /* pid or -pgrp where SIGIO should be sent */
688 uid_t uid, euid; /* uid/euid of process setting the owner */
689 int signum; /* posix.1b rt signal to be delivered on IO */
693 * Track a single file's readahead state
695 struct file_ra_state {
696 unsigned long start; /* Current window */
698 unsigned long flags; /* ra flags RA_FLAG_xxx*/
699 unsigned long cache_hit; /* cache hit count*/
700 unsigned long prev_page; /* Cache last read() position */
701 unsigned long ahead_start; /* Ahead window */
702 unsigned long ahead_size;
703 unsigned long ra_pages; /* Maximum readahead window */
704 unsigned long mmap_hit; /* Cache hit stat for mmap accesses */
705 unsigned long mmap_miss; /* Cache miss stat for mmap accesses */
707 #define RA_FLAG_MISS 0x01 /* a cache miss occured against this file */
708 #define RA_FLAG_INCACHE 0x02 /* file is already in cache */
712 * fu_list becomes invalid after file_free is called and queued via
713 * fu_rcuhead for RCU freeing
716 struct list_head fu_list;
717 struct rcu_head fu_rcuhead;
719 struct dentry *f_dentry;
720 struct vfsmount *f_vfsmnt;
721 const struct file_operations *f_op;
723 unsigned int f_flags;
726 struct fown_struct f_owner;
727 unsigned int f_uid, f_gid;
728 struct file_ra_state f_ra;
730 unsigned long f_version;
731 #ifdef CONFIG_SECURITY
734 /* needed for tty driver, and maybe others */
738 /* Used by fs/eventpoll.c to link all the hooks to this file */
739 struct list_head f_ep_links;
740 spinlock_t f_ep_lock;
741 #endif /* #ifdef CONFIG_EPOLL */
742 struct address_space *f_mapping;
744 extern spinlock_t files_lock;
745 #define file_list_lock() spin_lock(&files_lock);
746 #define file_list_unlock() spin_unlock(&files_lock);
748 #define get_file(x) atomic_inc(&(x)->f_count)
749 #define file_count(x) atomic_read(&(x)->f_count)
751 #define MAX_NON_LFS ((1UL<<31) - 1)
753 /* Page cache limit. The filesystems should put that into their s_maxbytes
754 limits, otherwise bad things can happen in VM. */
755 #if BITS_PER_LONG==32
756 #define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1)
757 #elif BITS_PER_LONG==64
758 #define MAX_LFS_FILESIZE 0x7fffffffffffffffUL
763 #define FL_ACCESS 8 /* not trying to lock, just looking */
764 #define FL_EXISTS 16 /* when unlocking, test for existence */
765 #define FL_LEASE 32 /* lease held on this file */
766 #define FL_CLOSE 64 /* unlock on close */
767 #define FL_SLEEP 128 /* A blocking lock */
770 * The POSIX file lock owner is determined by
771 * the "struct files_struct" in the thread group
772 * (or NULL for no owner - BSD locks).
774 * Lockd stuffs a "host" pointer into this.
776 typedef struct files_struct *fl_owner_t;
778 struct file_lock_operations {
779 void (*fl_insert)(struct file_lock *); /* lock insertion callback */
780 void (*fl_remove)(struct file_lock *); /* lock removal callback */
781 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
782 void (*fl_release_private)(struct file_lock *);
785 struct lock_manager_operations {
786 int (*fl_compare_owner)(struct file_lock *, struct file_lock *);
787 void (*fl_notify)(struct file_lock *); /* unblock callback */
788 void (*fl_copy_lock)(struct file_lock *, struct file_lock *);
789 void (*fl_release_private)(struct file_lock *);
790 void (*fl_break)(struct file_lock *);
791 int (*fl_mylease)(struct file_lock *, struct file_lock *);
792 int (*fl_change)(struct file_lock **, int);
795 /* that will die - we need it for nfs_lock_info */
796 #include <linux/nfs_fs_i.h>
799 struct file_lock *fl_next; /* singly linked list for this inode */
800 struct list_head fl_link; /* doubly linked list of all locks */
801 struct list_head fl_block; /* circular list of blocked processes */
804 wait_queue_head_t fl_wait;
805 struct file *fl_file;
806 unsigned char fl_flags;
807 unsigned char fl_type;
811 struct fasync_struct * fl_fasync; /* for lease break notifications */
812 unsigned long fl_break_time; /* for nonblocking lease breaks */
814 struct file_lock_operations *fl_ops; /* Callbacks for filesystems */
815 struct lock_manager_operations *fl_lmops; /* Callbacks for lockmanagers */
817 struct nfs_lock_info nfs_fl;
818 struct nfs4_lock_info nfs4_fl;
822 /* The following constant reflects the upper bound of the file/locking space */
824 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
825 #define OFFSET_MAX INT_LIMIT(loff_t)
826 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
829 #include <linux/fcntl.h>
831 extern int fcntl_getlk(struct file *, struct flock __user *);
832 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
833 struct flock __user *);
835 #if BITS_PER_LONG == 32
836 extern int fcntl_getlk64(struct file *, struct flock64 __user *);
837 extern int fcntl_setlk64(unsigned int, struct file *, unsigned int,
838 struct flock64 __user *);
841 extern void send_sigio(struct fown_struct *fown, int fd, int band);
842 extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
843 extern int fcntl_getlease(struct file *filp);
846 extern int do_sync_file_range(struct file *file, loff_t offset, loff_t endbyte,
850 extern void locks_init_lock(struct file_lock *);
851 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
852 extern void locks_remove_posix(struct file *, fl_owner_t);
853 extern void locks_remove_flock(struct file *);
854 extern int posix_test_lock(struct file *, struct file_lock *, struct file_lock *);
855 extern int posix_lock_file_conf(struct file *, struct file_lock *, struct file_lock *);
856 extern int posix_lock_file(struct file *, struct file_lock *);
857 extern int posix_lock_file_wait(struct file *, struct file_lock *);
858 extern int posix_unblock_lock(struct file *, struct file_lock *);
859 extern int flock_lock_file_wait(struct file *filp, struct file_lock *fl);
860 extern int __break_lease(struct inode *inode, unsigned int flags);
861 extern void lease_get_mtime(struct inode *, struct timespec *time);
862 extern int setlease(struct file *, long, struct file_lock **);
863 extern int lease_modify(struct file_lock **, int);
864 extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
865 extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
867 struct fasync_struct {
870 struct fasync_struct *fa_next; /* singly linked list */
871 struct file *fa_file;
874 #define FASYNC_MAGIC 0x4601
876 /* SMP safe fasync helpers: */
877 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
878 /* can be called from interrupts */
879 extern void kill_fasync(struct fasync_struct **, int, int);
880 /* only for net: no internal synchronization */
881 extern void __kill_fasync(struct fasync_struct *, int, int);
883 extern int f_setown(struct file *filp, unsigned long arg, int force);
884 extern void f_delown(struct file *filp);
885 extern int send_sigurg(struct fown_struct *fown);
891 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
892 #define MNT_DETACH 0x00000002 /* Just detach from the tree */
893 #define MNT_EXPIRE 0x00000004 /* Mark for expiry */
895 extern struct list_head super_blocks;
896 extern spinlock_t sb_lock;
898 #define sb_entry(list) list_entry((list), struct super_block, s_list)
899 #define S_BIAS (1<<30)
901 struct list_head s_list; /* Keep this first */
902 dev_t s_dev; /* search index; _not_ kdev_t */
903 unsigned long s_blocksize;
904 unsigned char s_blocksize_bits;
905 unsigned char s_dirt;
906 unsigned long long s_maxbytes; /* Max file size */
907 struct file_system_type *s_type;
908 struct super_operations *s_op;
909 struct dquot_operations *dq_op;
910 struct quotactl_ops *s_qcop;
911 struct export_operations *s_export_op;
912 unsigned long s_flags;
913 unsigned long s_magic;
914 struct dentry *s_root;
915 struct rw_semaphore s_umount;
921 #ifdef CONFIG_SECURITY
924 struct xattr_handler **s_xattr;
926 struct list_head s_inodes; /* all inodes */
927 struct list_head s_dirty; /* dirty inodes */
928 struct list_head s_io; /* parked for writeback */
929 struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */
930 struct list_head s_files;
932 struct block_device *s_bdev;
933 struct list_head s_instances;
934 struct quota_info s_dquot; /* Diskquota specific options */
937 wait_queue_head_t s_wait_unfrozen;
939 char s_id[32]; /* Informational name */
941 void *s_fs_info; /* Filesystem private info */
944 * The next field is for VFS *only*. No filesystems have any business
945 * even looking at it. You had been warned.
947 struct mutex s_vfs_rename_mutex; /* Kludge */
949 /* Granularity of c/m/atime in ns.
950 Cannot be worse than a second */
954 extern struct timespec current_fs_time(struct super_block *sb);
957 * Snapshotting support.
965 #define vfs_check_frozen(sb, level) \
966 wait_event((sb)->s_wait_unfrozen, ((sb)->s_frozen < (level)))
968 static inline void get_fs_excl(void)
970 atomic_inc(¤t->fs_excl);
973 static inline void put_fs_excl(void)
975 atomic_dec(¤t->fs_excl);
978 static inline int has_fs_excl(void)
980 return atomic_read(¤t->fs_excl);
985 * Superblock locking.
987 static inline void lock_super(struct super_block * sb)
990 mutex_lock(&sb->s_lock);
993 static inline void unlock_super(struct super_block * sb)
996 mutex_unlock(&sb->s_lock);
1000 * VFS helper functions..
1002 extern int vfs_permission(struct nameidata *, int);
1003 extern int vfs_create(struct inode *, struct dentry *, int, struct nameidata *);
1004 extern int vfs_mkdir(struct inode *, struct dentry *, int);
1005 extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
1006 extern int vfs_symlink(struct inode *, struct dentry *, const char *, int);
1007 extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
1008 extern int vfs_rmdir(struct inode *, struct dentry *);
1009 extern int vfs_unlink(struct inode *, struct dentry *);
1010 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1013 * VFS dentry helper functions.
1015 extern void dentry_unhash(struct dentry *dentry);
1018 * VFS file helper functions.
1020 extern int file_permission(struct file *, int);
1025 * NOTE! These match bits 12..15 of stat.st_mode
1026 * (ie "(i_mode >> 12) & 15").
1028 #define DT_UNKNOWN 0
1038 #define OSYNC_METADATA (1<<0)
1039 #define OSYNC_DATA (1<<1)
1040 #define OSYNC_INODE (1<<2)
1041 int generic_osync_inode(struct inode *, struct address_space *, int);
1044 * This is the "filldir" function type, used by readdir() to let
1045 * the kernel specify what kind of dirent layout it wants to have.
1046 * This allows the kernel to read directories into kernel space or
1047 * to have different dirent layouts depending on the binary type.
1049 typedef int (*filldir_t)(void *, const char *, int, loff_t, ino_t, unsigned);
1051 struct block_device_operations {
1052 int (*open) (struct inode *, struct file *);
1053 int (*release) (struct inode *, struct file *);
1054 int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
1055 long (*unlocked_ioctl) (struct file *, unsigned, unsigned long);
1056 long (*compat_ioctl) (struct file *, unsigned, unsigned long);
1057 int (*direct_access) (struct block_device *, sector_t, unsigned long *);
1058 int (*media_changed) (struct gendisk *);
1059 int (*revalidate_disk) (struct gendisk *);
1060 int (*getgeo)(struct block_device *, struct hd_geometry *);
1061 struct module *owner;
1065 * "descriptor" for what we're up to with a read for sendfile().
1066 * This allows us to use the same read code yet
1067 * have multiple different users of the data that
1068 * we read from a file.
1070 * The simplest case just copies the data to user
1081 } read_descriptor_t;
1083 typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long);
1085 /* These macros are for out of kernel modules to test that
1086 * the kernel supports the unlocked_ioctl and compat_ioctl
1087 * fields in struct file_operations. */
1088 #define HAVE_COMPAT_IOCTL 1
1089 #define HAVE_UNLOCKED_IOCTL 1
1093 * read, write, poll, fsync, readv, writev, unlocked_ioctl and compat_ioctl
1094 * can be called without the big kernel lock held in all filesystems.
1096 struct file_operations {
1097 struct module *owner;
1098 loff_t (*llseek) (struct file *, loff_t, int);
1099 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
1100 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
1101 ssize_t (*aio_read) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1102 ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t);
1103 int (*readdir) (struct file *, void *, filldir_t);
1104 unsigned int (*poll) (struct file *, struct poll_table_struct *);
1105 int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
1106 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
1107 long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
1108 int (*mmap) (struct file *, struct vm_area_struct *);
1109 int (*open) (struct inode *, struct file *);
1110 int (*flush) (struct file *, fl_owner_t id);
1111 int (*release) (struct inode *, struct file *);
1112 int (*fsync) (struct file *, struct dentry *, int datasync);
1113 int (*aio_fsync) (struct kiocb *, int datasync);
1114 int (*fasync) (int, struct file *, int);
1115 int (*lock) (struct file *, int, struct file_lock *);
1116 ssize_t (*sendfile) (struct file *, loff_t *, size_t, read_actor_t, void *);
1117 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
1118 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
1119 int (*check_flags)(int);
1120 int (*dir_notify)(struct file *filp, unsigned long arg);
1121 int (*flock) (struct file *, int, struct file_lock *);
1122 ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
1123 ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
1126 struct inode_operations {
1127 int (*create) (struct inode *,struct dentry *,int, struct nameidata *);
1128 struct dentry * (*lookup) (struct inode *,struct dentry *, struct nameidata *);
1129 int (*link) (struct dentry *,struct inode *,struct dentry *);
1130 int (*unlink) (struct inode *,struct dentry *);
1131 int (*symlink) (struct inode *,struct dentry *,const char *);
1132 int (*mkdir) (struct inode *,struct dentry *,int);
1133 int (*rmdir) (struct inode *,struct dentry *);
1134 int (*mknod) (struct inode *,struct dentry *,int,dev_t);
1135 int (*rename) (struct inode *, struct dentry *,
1136 struct inode *, struct dentry *);
1137 int (*readlink) (struct dentry *, char __user *,int);
1138 void * (*follow_link) (struct dentry *, struct nameidata *);
1139 void (*put_link) (struct dentry *, struct nameidata *, void *);
1140 void (*truncate) (struct inode *);
1141 int (*permission) (struct inode *, int, struct nameidata *);
1142 int (*setattr) (struct dentry *, struct iattr *);
1143 int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
1144 int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
1145 ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
1146 ssize_t (*listxattr) (struct dentry *, char *, size_t);
1147 int (*removexattr) (struct dentry *, const char *);
1148 void (*truncate_range)(struct inode *, loff_t, loff_t);
1153 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
1154 unsigned long nr_segs, unsigned long fast_segs,
1155 struct iovec *fast_pointer,
1156 struct iovec **ret_pointer);
1158 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
1159 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
1160 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,
1161 unsigned long, loff_t *);
1162 extern ssize_t vfs_writev(struct file *, const struct iovec __user *,
1163 unsigned long, loff_t *);
1166 * NOTE: write_inode, delete_inode, clear_inode, put_inode can be called
1167 * without the big kernel lock held in all filesystems.
1169 struct super_operations {
1170 struct inode *(*alloc_inode)(struct super_block *sb);
1171 void (*destroy_inode)(struct inode *);
1173 void (*read_inode) (struct inode *);
1175 void (*dirty_inode) (struct inode *);
1176 int (*write_inode) (struct inode *, int);
1177 void (*put_inode) (struct inode *);
1178 void (*drop_inode) (struct inode *);
1179 void (*delete_inode) (struct inode *);
1180 void (*put_super) (struct super_block *);
1181 void (*write_super) (struct super_block *);
1182 int (*sync_fs)(struct super_block *sb, int wait);
1183 void (*write_super_lockfs) (struct super_block *);
1184 void (*unlockfs) (struct super_block *);
1185 int (*statfs) (struct dentry *, struct kstatfs *);
1186 int (*remount_fs) (struct super_block *, int *, char *);
1187 void (*clear_inode) (struct inode *);
1188 void (*umount_begin) (struct vfsmount *, int);
1190 int (*show_options)(struct seq_file *, struct vfsmount *);
1191 int (*show_stats)(struct seq_file *, struct vfsmount *);
1193 ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
1194 ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
1198 /* Inode state bits. Protected by inode_lock. */
1199 #define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */
1200 #define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */
1201 #define I_DIRTY_PAGES 4 /* Data-related inode changes pending */
1203 #define I_LOCK (1 << __I_LOCK)
1204 #define I_FREEING 16
1207 #define I_WILL_FREE 128
1209 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
1211 extern void __mark_inode_dirty(struct inode *, int);
1212 static inline void mark_inode_dirty(struct inode *inode)
1214 __mark_inode_dirty(inode, I_DIRTY);
1217 static inline void mark_inode_dirty_sync(struct inode *inode)
1219 __mark_inode_dirty(inode, I_DIRTY_SYNC);
1222 static inline void inc_nlink(struct inode *inode)
1227 static inline void inode_inc_link_count(struct inode *inode)
1230 mark_inode_dirty(inode);
1233 static inline void drop_nlink(struct inode *inode)
1238 static inline void clear_nlink(struct inode *inode)
1243 static inline void inode_dec_link_count(struct inode *inode)
1246 mark_inode_dirty(inode);
1249 extern void touch_atime(struct vfsmount *mnt, struct dentry *dentry);
1250 static inline void file_accessed(struct file *file)
1252 if (!(file->f_flags & O_NOATIME))
1253 touch_atime(file->f_vfsmnt, file->f_dentry);
1256 int sync_inode(struct inode *inode, struct writeback_control *wbc);
1259 * struct export_operations - for nfsd to communicate with file systems
1260 * @decode_fh: decode a file handle fragment and return a &struct dentry
1261 * @encode_fh: encode a file handle fragment from a dentry
1262 * @get_name: find the name for a given inode in a given directory
1263 * @get_parent: find the parent of a given directory
1264 * @get_dentry: find a dentry for the inode given a file handle sub-fragment
1265 * @find_exported_dentry:
1266 * set by the exporting module to a standard helper function.
1269 * The export_operations structure provides a means for nfsd to communicate
1270 * with a particular exported file system - particularly enabling nfsd and
1271 * the filesystem to co-operate when dealing with file handles.
1273 * export_operations contains two basic operation for dealing with file
1274 * handles, decode_fh() and encode_fh(), and allows for some other
1275 * operations to be defined which standard helper routines use to get
1276 * specific information from the filesystem.
1278 * nfsd encodes information use to determine which filesystem a filehandle
1279 * applies to in the initial part of the file handle. The remainder, termed
1280 * a file handle fragment, is controlled completely by the filesystem. The
1281 * standard helper routines assume that this fragment will contain one or
1282 * two sub-fragments, one which identifies the file, and one which may be
1283 * used to identify the (a) directory containing the file.
1285 * In some situations, nfsd needs to get a dentry which is connected into a
1286 * specific part of the file tree. To allow for this, it passes the
1287 * function acceptable() together with a @context which can be used to see
1288 * if the dentry is acceptable. As there can be multiple dentrys for a
1289 * given file, the filesystem should check each one for acceptability before
1290 * looking for the next. As soon as an acceptable one is found, it should
1294 * @decode_fh is given a &struct super_block (@sb), a file handle fragment
1295 * (@fh, @fh_len) and an acceptability testing function (@acceptable,
1296 * @context). It should return a &struct dentry which refers to the same
1297 * file that the file handle fragment refers to, and which passes the
1298 * acceptability test. If it cannot, it should return a %NULL pointer if
1299 * the file was found but no acceptable &dentries were available, or a
1300 * %ERR_PTR error code indicating why it couldn't be found (e.g. %ENOENT or
1304 * @encode_fh should store in the file handle fragment @fh (using at most
1305 * @max_len bytes) information that can be used by @decode_fh to recover the
1306 * file refered to by the &struct dentry @de. If the @connectable flag is
1307 * set, the encode_fh() should store sufficient information so that a good
1308 * attempt can be made to find not only the file but also it's place in the
1309 * filesystem. This typically means storing a reference to de->d_parent in
1310 * the filehandle fragment. encode_fh() should return the number of bytes
1311 * stored or a negative error code such as %-ENOSPC
1314 * @get_name should find a name for the given @child in the given @parent
1315 * directory. The name should be stored in the @name (with the
1316 * understanding that it is already pointing to a a %NAME_MAX+1 sized
1317 * buffer. get_name() should return %0 on success, a negative error code
1318 * or error. @get_name will be called without @parent->i_mutex held.
1321 * @get_parent should find the parent directory for the given @child which
1322 * is also a directory. In the event that it cannot be found, or storage
1323 * space cannot be allocated, a %ERR_PTR should be returned.
1326 * Given a &super_block (@sb) and a pointer to a file-system specific inode
1327 * identifier, possibly an inode number, (@inump) get_dentry() should find
1328 * the identified inode and return a dentry for that inode. Any suitable
1329 * dentry can be returned including, if necessary, a new dentry created with
1330 * d_alloc_root. The caller can then find any other extant dentrys by
1331 * following the d_alias links. If a new dentry was created using
1332 * d_alloc_root, DCACHE_NFSD_DISCONNECTED should be set, and the dentry
1333 * should be d_rehash()ed.
1335 * If the inode cannot be found, either a %NULL pointer or an %ERR_PTR code
1336 * can be returned. The @inump will be whatever was passed to
1337 * nfsd_find_fh_dentry() in either the @obj or @parent parameters.
1340 * get_parent is called with child->d_inode->i_mutex down
1341 * get_name is not (which is possibly inconsistent)
1344 struct export_operations {
1345 struct dentry *(*decode_fh)(struct super_block *sb, __u32 *fh, int fh_len, int fh_type,
1346 int (*acceptable)(void *context, struct dentry *de),
1348 int (*encode_fh)(struct dentry *de, __u32 *fh, int *max_len,
1351 /* the following are only called from the filesystem itself */
1352 int (*get_name)(struct dentry *parent, char *name,
1353 struct dentry *child);
1354 struct dentry * (*get_parent)(struct dentry *child);
1355 struct dentry * (*get_dentry)(struct super_block *sb, void *inump);
1357 /* This is set by the exporting module to a standard helper */
1358 struct dentry * (*find_exported_dentry)(
1359 struct super_block *sb, void *obj, void *parent,
1360 int (*acceptable)(void *context, struct dentry *de),
1366 extern struct dentry *
1367 find_exported_dentry(struct super_block *sb, void *obj, void *parent,
1368 int (*acceptable)(void *context, struct dentry *de),
1371 struct file_system_type {
1374 int (*get_sb) (struct file_system_type *, int,
1375 const char *, void *, struct vfsmount *);
1376 void (*kill_sb) (struct super_block *);
1377 struct module *owner;
1378 struct file_system_type * next;
1379 struct list_head fs_supers;
1380 struct lock_class_key s_lock_key;
1381 struct lock_class_key s_umount_key;
1384 extern int get_sb_bdev(struct file_system_type *fs_type,
1385 int flags, const char *dev_name, void *data,
1386 int (*fill_super)(struct super_block *, void *, int),
1387 struct vfsmount *mnt);
1388 extern int get_sb_single(struct file_system_type *fs_type,
1389 int flags, void *data,
1390 int (*fill_super)(struct super_block *, void *, int),
1391 struct vfsmount *mnt);
1392 extern int get_sb_nodev(struct file_system_type *fs_type,
1393 int flags, void *data,
1394 int (*fill_super)(struct super_block *, void *, int),
1395 struct vfsmount *mnt);
1396 void generic_shutdown_super(struct super_block *sb);
1397 void kill_block_super(struct super_block *sb);
1398 void kill_anon_super(struct super_block *sb);
1399 void kill_litter_super(struct super_block *sb);
1400 void deactivate_super(struct super_block *sb);
1401 int set_anon_super(struct super_block *s, void *data);
1402 struct super_block *sget(struct file_system_type *type,
1403 int (*test)(struct super_block *,void *),
1404 int (*set)(struct super_block *,void *),
1406 extern int get_sb_pseudo(struct file_system_type *, char *,
1407 struct super_operations *ops, unsigned long,
1408 struct vfsmount *mnt);
1409 extern int simple_set_mnt(struct vfsmount *mnt, struct super_block *sb);
1410 int __put_super(struct super_block *sb);
1411 int __put_super_and_need_restart(struct super_block *sb);
1412 void unnamed_dev_init(void);
1414 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
1415 #define fops_get(fops) \
1416 (((fops) && try_module_get((fops)->owner) ? (fops) : NULL))
1417 #define fops_put(fops) \
1418 do { if (fops) module_put((fops)->owner); } while(0)
1420 extern int register_filesystem(struct file_system_type *);
1421 extern int unregister_filesystem(struct file_system_type *);
1422 extern struct vfsmount *kern_mount(struct file_system_type *);
1423 extern int may_umount_tree(struct vfsmount *);
1424 extern int may_umount(struct vfsmount *);
1425 extern void umount_tree(struct vfsmount *, int, struct list_head *);
1426 extern void release_mounts(struct list_head *);
1427 extern long do_mount(char *, char *, char *, unsigned long, void *);
1428 extern struct vfsmount *copy_tree(struct vfsmount *, struct dentry *, int);
1429 extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
1432 extern int vfs_statfs(struct dentry *, struct kstatfs *);
1435 extern struct subsystem fs_subsys;
1437 #define FLOCK_VERIFY_READ 1
1438 #define FLOCK_VERIFY_WRITE 2
1440 extern int locks_mandatory_locked(struct inode *);
1441 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
1444 * Candidates for mandatory locking have the setgid bit set
1445 * but no group execute bit - an otherwise meaningless combination.
1447 #define MANDATORY_LOCK(inode) \
1448 (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
1450 static inline int locks_verify_locked(struct inode *inode)
1452 if (MANDATORY_LOCK(inode))
1453 return locks_mandatory_locked(inode);
1457 extern int rw_verify_area(int, struct file *, loff_t *, size_t);
1459 static inline int locks_verify_truncate(struct inode *inode,
1463 if (inode->i_flock && MANDATORY_LOCK(inode))
1464 return locks_mandatory_area(
1465 FLOCK_VERIFY_WRITE, inode, filp,
1466 size < inode->i_size ? size : inode->i_size,
1467 (size < inode->i_size ? inode->i_size - size
1468 : size - inode->i_size)
1473 static inline int break_lease(struct inode *inode, unsigned int mode)
1476 return __break_lease(inode, mode);
1482 extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
1484 extern long do_sys_open(int fdf, const char __user *filename, int flags,
1486 extern struct file *filp_open(const char *, int, int);
1487 extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
1488 extern int filp_close(struct file *, fl_owner_t id);
1489 extern char * getname(const char __user *);
1492 extern void __init vfs_caches_init_early(void);
1493 extern void __init vfs_caches_init(unsigned long);
1495 #define __getname() kmem_cache_alloc(names_cachep, SLAB_KERNEL)
1496 #define __putname(name) kmem_cache_free(names_cachep, (void *)(name))
1497 #ifndef CONFIG_AUDITSYSCALL
1498 #define putname(name) __putname(name)
1500 extern void putname(const char *name);
1504 extern int register_blkdev(unsigned int, const char *);
1505 extern int unregister_blkdev(unsigned int, const char *);
1506 extern struct block_device *bdget(dev_t);
1507 extern void bd_set_size(struct block_device *, loff_t size);
1508 extern void bd_forget(struct inode *inode);
1509 extern void bdput(struct block_device *);
1510 extern struct block_device *open_by_devnum(dev_t, unsigned);
1511 extern struct block_device *open_partition_by_devnum(dev_t, unsigned);
1512 extern const struct address_space_operations def_blk_aops;
1514 static inline void bd_forget(struct inode *inode) {}
1516 extern const struct file_operations def_blk_fops;
1517 extern const struct file_operations def_chr_fops;
1518 extern const struct file_operations bad_sock_fops;
1519 extern const struct file_operations def_fifo_fops;
1521 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
1522 extern int blkdev_ioctl(struct inode *, struct file *, unsigned, unsigned long);
1523 extern long compat_blkdev_ioctl(struct file *, unsigned, unsigned long);
1524 extern int blkdev_get(struct block_device *, mode_t, unsigned);
1525 extern int blkdev_put(struct block_device *);
1526 extern int blkdev_put_partition(struct block_device *);
1527 extern int bd_claim(struct block_device *, void *);
1528 extern void bd_release(struct block_device *);
1530 extern int bd_claim_by_disk(struct block_device *, void *, struct gendisk *);
1531 extern void bd_release_from_disk(struct block_device *, struct gendisk *);
1533 #define bd_claim_by_disk(bdev, holder, disk) bd_claim(bdev, holder)
1534 #define bd_release_from_disk(bdev, disk) bd_release(bdev)
1539 #define CHRDEV_MAJOR_HASH_SIZE 255
1540 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
1541 extern int register_chrdev_region(dev_t, unsigned, const char *);
1542 extern int register_chrdev(unsigned int, const char *,
1543 const struct file_operations *);
1544 extern int unregister_chrdev(unsigned int, const char *);
1545 extern void unregister_chrdev_region(dev_t, unsigned);
1546 extern int chrdev_open(struct inode *, struct file *);
1547 extern void chrdev_show(struct seq_file *,off_t);
1549 /* fs/block_dev.c */
1550 #define BDEVNAME_SIZE 32 /* Largest string for a blockdev identifier */
1553 #define BLKDEV_MAJOR_HASH_SIZE 255
1554 extern const char *__bdevname(dev_t, char *buffer);
1555 extern const char *bdevname(struct block_device *bdev, char *buffer);
1556 extern struct block_device *lookup_bdev(const char *);
1557 extern struct block_device *open_bdev_excl(const char *, int, void *);
1558 extern void close_bdev_excl(struct block_device *);
1559 extern void blkdev_show(struct seq_file *,off_t);
1561 #define BLKDEV_MAJOR_HASH_SIZE 0
1564 extern void init_special_inode(struct inode *, umode_t, dev_t);
1566 /* Invalid inode operations -- fs/bad_inode.c */
1567 extern void make_bad_inode(struct inode *);
1568 extern int is_bad_inode(struct inode *);
1570 extern const struct file_operations read_fifo_fops;
1571 extern const struct file_operations write_fifo_fops;
1572 extern const struct file_operations rdwr_fifo_fops;
1574 extern int fs_may_remount_ro(struct super_block *);
1578 * return READ, READA, or WRITE
1580 #define bio_rw(bio) ((bio)->bi_rw & (RW_MASK | RWA_MASK))
1583 * return data direction, READ or WRITE
1585 #define bio_data_dir(bio) ((bio)->bi_rw & 1)
1587 extern int check_disk_change(struct block_device *);
1588 extern int __invalidate_device(struct block_device *);
1589 extern int invalidate_partition(struct gendisk *, int);
1591 extern int invalidate_inodes(struct super_block *);
1592 unsigned long invalidate_mapping_pages(struct address_space *mapping,
1593 pgoff_t start, pgoff_t end);
1594 unsigned long invalidate_inode_pages(struct address_space *mapping);
1595 static inline void invalidate_remote_inode(struct inode *inode)
1597 if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
1598 S_ISLNK(inode->i_mode))
1599 invalidate_inode_pages(inode->i_mapping);
1601 extern int invalidate_inode_pages2(struct address_space *mapping);
1602 extern int invalidate_inode_pages2_range(struct address_space *mapping,
1603 pgoff_t start, pgoff_t end);
1604 extern int write_inode_now(struct inode *, int);
1605 extern int filemap_fdatawrite(struct address_space *);
1606 extern int filemap_flush(struct address_space *);
1607 extern int filemap_fdatawait(struct address_space *);
1608 extern int filemap_write_and_wait(struct address_space *mapping);
1609 extern int filemap_write_and_wait_range(struct address_space *mapping,
1610 loff_t lstart, loff_t lend);
1611 extern int wait_on_page_writeback_range(struct address_space *mapping,
1612 pgoff_t start, pgoff_t end);
1613 extern int __filemap_fdatawrite_range(struct address_space *mapping,
1614 loff_t start, loff_t end, int sync_mode);
1616 extern long do_fsync(struct file *file, int datasync);
1617 extern void sync_supers(void);
1618 extern void sync_filesystems(int wait);
1619 extern void __fsync_super(struct super_block *sb);
1620 extern void emergency_sync(void);
1621 extern void emergency_remount(void);
1622 extern int do_remount_sb(struct super_block *sb, int flags,
1623 void *data, int force);
1625 extern sector_t bmap(struct inode *, sector_t);
1627 extern int notify_change(struct dentry *, struct iattr *);
1628 extern int permission(struct inode *, int, struct nameidata *);
1629 extern int generic_permission(struct inode *, int,
1630 int (*check_acl)(struct inode *, int));
1632 extern int get_write_access(struct inode *);
1633 extern int deny_write_access(struct file *);
1634 static inline void put_write_access(struct inode * inode)
1636 atomic_dec(&inode->i_writecount);
1638 static inline void allow_write_access(struct file *file)
1641 atomic_inc(&file->f_dentry->d_inode->i_writecount);
1643 extern int do_pipe(int *);
1645 extern int open_namei(int dfd, const char *, int, int, struct nameidata *);
1646 extern int may_open(struct nameidata *, int, int);
1648 extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
1649 extern struct file * open_exec(const char *);
1651 /* fs/dcache.c -- generic fs support functions */
1652 extern int is_subdir(struct dentry *, struct dentry *);
1653 extern ino_t find_inode_number(struct dentry *, struct qstr *);
1655 #include <linux/err.h>
1657 /* needed for stackable file system support */
1658 extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
1660 extern loff_t vfs_llseek(struct file *file, loff_t offset, int origin);
1662 extern void inode_init_once(struct inode *);
1663 extern void iput(struct inode *);
1664 extern struct inode * igrab(struct inode *);
1665 extern ino_t iunique(struct super_block *, ino_t);
1666 extern int inode_needs_sync(struct inode *inode);
1667 extern void generic_delete_inode(struct inode *inode);
1668 extern void generic_drop_inode(struct inode *inode);
1670 extern struct inode *ilookup5_nowait(struct super_block *sb,
1671 unsigned long hashval, int (*test)(struct inode *, void *),
1673 extern struct inode *ilookup5(struct super_block *sb, unsigned long hashval,
1674 int (*test)(struct inode *, void *), void *data);
1675 extern struct inode *ilookup(struct super_block *sb, unsigned long ino);
1677 extern struct inode * iget5_locked(struct super_block *, unsigned long, int (*test)(struct inode *, void *), int (*set)(struct inode *, void *), void *);
1678 extern struct inode * iget_locked(struct super_block *, unsigned long);
1679 extern void unlock_new_inode(struct inode *);
1681 static inline struct inode *iget(struct super_block *sb, unsigned long ino)
1683 struct inode *inode = iget_locked(sb, ino);
1685 if (inode && (inode->i_state & I_NEW)) {
1686 sb->s_op->read_inode(inode);
1687 unlock_new_inode(inode);
1693 extern void __iget(struct inode * inode);
1694 extern void clear_inode(struct inode *);
1695 extern void destroy_inode(struct inode *);
1696 extern struct inode *new_inode(struct super_block *);
1697 extern int remove_suid(struct dentry *);
1698 extern void remove_dquot_ref(struct super_block *, int, struct list_head *);
1700 extern void __insert_inode_hash(struct inode *, unsigned long hashval);
1701 extern void remove_inode_hash(struct inode *);
1702 static inline void insert_inode_hash(struct inode *inode) {
1703 __insert_inode_hash(inode, inode->i_ino);
1706 extern struct file * get_empty_filp(void);
1707 extern void file_move(struct file *f, struct list_head *list);
1708 extern void file_kill(struct file *f);
1711 extern void submit_bio(int, struct bio *);
1712 extern int bdev_read_only(struct block_device *);
1714 extern int set_blocksize(struct block_device *, int);
1715 extern int sb_set_blocksize(struct super_block *, int);
1716 extern int sb_min_blocksize(struct super_block *, int);
1718 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
1719 extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
1720 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1721 extern int file_send_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1722 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
1723 extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
1724 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
1725 extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
1726 unsigned long, loff_t);
1727 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
1728 unsigned long *, loff_t, loff_t *, size_t, size_t);
1729 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
1730 unsigned long, loff_t, loff_t *, size_t, ssize_t);
1731 extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);
1732 extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
1733 extern ssize_t generic_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);
1734 extern void do_generic_mapping_read(struct address_space *mapping,
1735 struct file_ra_state *, struct file *,
1736 loff_t *, read_descriptor_t *, read_actor_t);
1739 extern ssize_t generic_file_splice_read(struct file *, loff_t *,
1740 struct pipe_inode_info *, size_t, unsigned int);
1741 extern ssize_t generic_file_splice_write(struct pipe_inode_info *,
1742 struct file *, loff_t *, size_t, unsigned int);
1743 extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
1744 struct file *out, loff_t *, size_t len, unsigned int flags);
1745 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
1746 size_t len, unsigned int flags);
1749 file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
1750 extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
1751 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
1752 extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
1753 extern int generic_file_open(struct inode * inode, struct file * filp);
1754 extern int nonseekable_open(struct inode * inode, struct file * filp);
1756 #ifdef CONFIG_FS_XIP
1757 extern ssize_t xip_file_read(struct file *filp, char __user *buf, size_t len,
1759 extern ssize_t xip_file_sendfile(struct file *in_file, loff_t *ppos,
1760 size_t count, read_actor_t actor,
1762 extern int xip_file_mmap(struct file * file, struct vm_area_struct * vma);
1763 extern ssize_t xip_file_write(struct file *filp, const char __user *buf,
1764 size_t len, loff_t *ppos);
1765 extern int xip_truncate_page(struct address_space *mapping, loff_t from);
1767 static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
1773 static inline void do_generic_file_read(struct file * filp, loff_t *ppos,
1774 read_descriptor_t * desc,
1777 do_generic_mapping_read(filp->f_mapping,
1786 ssize_t __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
1787 struct block_device *bdev, const struct iovec *iov, loff_t offset,
1788 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
1792 DIO_LOCKING = 1, /* need locking between buffered and direct access */
1793 DIO_NO_LOCKING, /* bdev; no locking at all between buffered/direct */
1794 DIO_OWN_LOCKING, /* filesystem locks buffered and direct internally */
1797 static inline ssize_t blockdev_direct_IO(int rw, struct kiocb *iocb,
1798 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1799 loff_t offset, unsigned long nr_segs, get_block_t get_block,
1800 dio_iodone_t end_io)
1802 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1803 nr_segs, get_block, end_io, DIO_LOCKING);
1806 static inline ssize_t blockdev_direct_IO_no_locking(int rw, struct kiocb *iocb,
1807 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1808 loff_t offset, unsigned long nr_segs, get_block_t get_block,
1809 dio_iodone_t end_io)
1811 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1812 nr_segs, get_block, end_io, DIO_NO_LOCKING);
1815 static inline ssize_t blockdev_direct_IO_own_locking(int rw, struct kiocb *iocb,
1816 struct inode *inode, struct block_device *bdev, const struct iovec *iov,
1817 loff_t offset, unsigned long nr_segs, get_block_t get_block,
1818 dio_iodone_t end_io)
1820 return __blockdev_direct_IO(rw, iocb, inode, bdev, iov, offset,
1821 nr_segs, get_block, end_io, DIO_OWN_LOCKING);
1825 extern const struct file_operations generic_ro_fops;
1827 #define special_file(m) (S_ISCHR(m)||S_ISBLK(m)||S_ISFIFO(m)||S_ISSOCK(m))
1829 extern int vfs_readlink(struct dentry *, char __user *, int, const char *);
1830 extern int vfs_follow_link(struct nameidata *, const char *);
1831 extern int page_readlink(struct dentry *, char __user *, int);
1832 extern void *page_follow_link_light(struct dentry *, struct nameidata *);
1833 extern void page_put_link(struct dentry *, struct nameidata *, void *);
1834 extern int __page_symlink(struct inode *inode, const char *symname, int len,
1836 extern int page_symlink(struct inode *inode, const char *symname, int len);
1837 extern struct inode_operations page_symlink_inode_operations;
1838 extern int generic_readlink(struct dentry *, char __user *, int);
1839 extern void generic_fillattr(struct inode *, struct kstat *);
1840 extern int vfs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1841 void inode_add_bytes(struct inode *inode, loff_t bytes);
1842 void inode_sub_bytes(struct inode *inode, loff_t bytes);
1843 loff_t inode_get_bytes(struct inode *inode);
1844 void inode_set_bytes(struct inode *inode, loff_t bytes);
1846 extern int vfs_readdir(struct file *, filldir_t, void *);
1848 extern int vfs_stat(char __user *, struct kstat *);
1849 extern int vfs_lstat(char __user *, struct kstat *);
1850 extern int vfs_stat_fd(int dfd, char __user *, struct kstat *);
1851 extern int vfs_lstat_fd(int dfd, char __user *, struct kstat *);
1852 extern int vfs_fstat(unsigned int, struct kstat *);
1854 extern int vfs_ioctl(struct file *, unsigned int, unsigned int, unsigned long);
1856 extern struct file_system_type *get_fs_type(const char *name);
1857 extern struct super_block *get_super(struct block_device *);
1858 extern struct super_block *user_get_super(dev_t);
1859 extern void drop_super(struct super_block *sb);
1861 extern int dcache_dir_open(struct inode *, struct file *);
1862 extern int dcache_dir_close(struct inode *, struct file *);
1863 extern loff_t dcache_dir_lseek(struct file *, loff_t, int);
1864 extern int dcache_readdir(struct file *, void *, filldir_t);
1865 extern int simple_getattr(struct vfsmount *, struct dentry *, struct kstat *);
1866 extern int simple_statfs(struct dentry *, struct kstatfs *);
1867 extern int simple_link(struct dentry *, struct inode *, struct dentry *);
1868 extern int simple_unlink(struct inode *, struct dentry *);
1869 extern int simple_rmdir(struct inode *, struct dentry *);
1870 extern int simple_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
1871 extern int simple_sync_file(struct file *, struct dentry *, int);
1872 extern int simple_empty(struct dentry *);
1873 extern int simple_readpage(struct file *file, struct page *page);
1874 extern int simple_prepare_write(struct file *file, struct page *page,
1875 unsigned offset, unsigned to);
1876 extern int simple_commit_write(struct file *file, struct page *page,
1877 unsigned offset, unsigned to);
1879 extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
1880 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);
1881 extern const struct file_operations simple_dir_operations;
1882 extern struct inode_operations simple_dir_inode_operations;
1883 struct tree_descr { char *name; const struct file_operations *ops; int mode; };
1884 struct dentry *d_alloc_name(struct dentry *, const char *);
1885 extern int simple_fill_super(struct super_block *, int, struct tree_descr *);
1886 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
1887 extern void simple_release_fs(struct vfsmount **mount, int *count);
1889 extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t);
1891 #ifdef CONFIG_MIGRATION
1892 extern int buffer_migrate_page(struct address_space *,
1893 struct page *, struct page *);
1895 #define buffer_migrate_page NULL
1898 extern int inode_change_ok(struct inode *, struct iattr *);
1899 extern int __must_check inode_setattr(struct inode *, struct iattr *);
1901 extern void file_update_time(struct file *file);
1903 static inline ino_t parent_ino(struct dentry *dentry)
1907 spin_lock(&dentry->d_lock);
1908 res = dentry->d_parent->d_inode->i_ino;
1909 spin_unlock(&dentry->d_lock);
1914 extern int unshare_files(void);
1916 /* Transaction based IO helpers */
1919 * An argresp is stored in an allocated page and holds the
1920 * size of the argument or response, along with its content
1922 struct simple_transaction_argresp {
1927 #define SIMPLE_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct simple_transaction_argresp))
1929 char *simple_transaction_get(struct file *file, const char __user *buf,
1931 ssize_t simple_transaction_read(struct file *file, char __user *buf,
1932 size_t size, loff_t *pos);
1933 int simple_transaction_release(struct inode *inode, struct file *file);
1935 static inline void simple_transaction_set(struct file *file, size_t n)
1937 struct simple_transaction_argresp *ar = file->private_data;
1939 BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
1942 * The barrier ensures that ar->size will really remain zero until
1943 * ar->data is ready for reading.
1950 * simple attribute files
1952 * These attributes behave similar to those in sysfs:
1954 * Writing to an attribute immediately sets a value, an open file can be
1955 * written to multiple times.
1957 * Reading from an attribute creates a buffer from the value that might get
1958 * read with multiple read calls. When the attribute has been read
1959 * completely, no further read calls are possible until the file is opened
1962 * All attributes contain a text representation of a numeric value
1963 * that are accessed with the get() and set() functions.
1965 #define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt) \
1966 static int __fops ## _open(struct inode *inode, struct file *file) \
1968 __simple_attr_check_format(__fmt, 0ull); \
1969 return simple_attr_open(inode, file, __get, __set, __fmt); \
1971 static struct file_operations __fops = { \
1972 .owner = THIS_MODULE, \
1973 .open = __fops ## _open, \
1974 .release = simple_attr_close, \
1975 .read = simple_attr_read, \
1976 .write = simple_attr_write, \
1979 static inline void __attribute__((format(printf, 1, 2)))
1980 __simple_attr_check_format(const char *fmt, ...)
1982 /* don't do anything, just let the compiler check the arguments; */
1985 int simple_attr_open(struct inode *inode, struct file *file,
1986 u64 (*get)(void *), void (*set)(void *, u64),
1988 int simple_attr_close(struct inode *inode, struct file *file);
1989 ssize_t simple_attr_read(struct file *file, char __user *buf,
1990 size_t len, loff_t *ppos);
1991 ssize_t simple_attr_write(struct file *file, const char __user *buf,
1992 size_t len, loff_t *ppos);
1995 #ifdef CONFIG_SECURITY
1996 static inline char *alloc_secdata(void)
1998 return (char *)get_zeroed_page(GFP_KERNEL);
2001 static inline void free_secdata(void *secdata)
2003 free_page((unsigned long)secdata);
2006 static inline char *alloc_secdata(void)
2011 static inline void free_secdata(void *secdata)
2013 #endif /* CONFIG_SECURITY */
2015 #endif /* __KERNEL__ */
2016 #endif /* _LINUX_FS_H */