5 * This file has definitions for some important file table
9 #include <linux/config.h>
10 #include <linux/linkage.h>
11 #include <linux/limits.h>
12 #include <linux/wait.h>
13 #include <linux/types.h>
14 #include <linux/vfs.h>
15 #include <linux/net.h>
16 #include <linux/kdev_t.h>
17 #include <linux/ioctl.h>
18 #include <linux/list.h>
19 #include <linux/dcache.h>
20 #include <linux/stat.h>
21 #include <linux/cache.h>
22 #include <linux/stddef.h>
23 #include <linux/string.h>
25 #include <asm/atomic.h>
26 #include <asm/bitops.h>
28 struct poll_table_struct;
32 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
33 * the file limit at runtime and only root can increase the per-process
34 * nr_file rlimit, so it's safe to set up a ridiculously high absolute
35 * upper limit on files-per-process.
37 * Some programs (notably those using select()) may have to be
38 * recompiled to take full advantage of the new limits..
41 /* Fixed constants first: */
43 #define NR_OPEN (1024*1024) /* Absolute upper limit on fd num */
44 #define INR_OPEN 1024 /* Initial setting for nfile rlimits */
46 #define BLOCK_SIZE_BITS 10
47 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
49 /* And dynamically-tunable limits and defaults: */
50 struct files_stat_struct {
51 int nr_files; /* read only */
52 int nr_free_files; /* read only */
53 int max_files; /* tunable */
55 extern struct files_stat_struct files_stat;
57 struct inodes_stat_t {
62 extern struct inodes_stat_t inodes_stat;
64 extern int max_super_blocks, nr_super_blocks;
65 extern int leases_enable, dir_notify_enable, lease_break_time;
67 #define NR_FILE 8192 /* this can well be larger on a larger system */
68 #define NR_RESERVED_FILES 10 /* reserved for root */
80 #define READA 2 /* read-ahead - don't block if no resources */
81 #define SPECIAL 4 /* For non-blockdevice requests in request queue */
87 /* public flags for file_system_type */
88 #define FS_REQUIRES_DEV 1
89 #define FS_NO_DCACHE 2 /* Only dcache the necessary things. */
90 #define FS_NO_PRELIM 4 /* prevent preloading of dentries, even if
91 * FS_NO_DCACHE is not set.
93 #define FS_SINGLE 8 /*
94 * Filesystem that can have only one superblock;
95 * kernel-wide vfsmnt is placed in ->kern_mnt by
96 * kern_mount() which must be called _after_
97 * register_filesystem().
99 #define FS_NOMOUNT 16 /* Never mount from userland */
100 #define FS_LITTER 32 /* Keeps the tree in dcache */
101 #define FS_ODD_RENAME 32768 /* Temporary stuff; will go away as soon
102 * as nfs_rename() will be cleaned up
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_NOATIME 1024 /* Do not update access times. */
115 #define MS_NODIRATIME 2048 /* Do not update directory access times */
119 * Flags that can be altered by MS_REMOUNT
121 #define MS_RMT_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|\
122 MS_SYNCHRONOUS|MS_MANDLOCK|MS_NOATIME|MS_NODIRATIME)
125 * Old magic mount flag and mask
127 #define MS_MGC_VAL 0xC0ED0000
128 #define MS_MGC_MSK 0xffff0000
130 /* Inode flags - they have nothing to superblock flags now */
132 #define S_SYNC 1 /* Writes are synced at once */
133 #define S_NOATIME 2 /* Do not update access times */
134 #define S_QUOTA 4 /* Quota initialized for file */
135 #define S_APPEND 8 /* Append-only file */
136 #define S_IMMUTABLE 16 /* Immutable file */
137 #define S_DEAD 32 /* removed, but still open directory */
140 * Note that nosuid etc flags are inode-specific: setting some file-system
141 * flags just means all the inodes inherit those flags by default. It might be
142 * possible to override it selectively if you really wanted to with some
143 * ioctl() that is not currently implemented.
145 * Exception: MS_RDONLY is always applied to the entire file system.
147 * Unfortunately, it is possible to change a filesystems flags with it mounted
148 * with files in use. This means that all of the inodes will not have their
149 * i_flags updated. Hence, i_flags no longer inherit the superblock mount
150 * flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
152 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
154 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
155 #define IS_NOSUID(inode) __IS_FLG(inode, MS_NOSUID)
156 #define IS_NODEV(inode) __IS_FLG(inode, MS_NODEV)
157 #define IS_NOEXEC(inode) __IS_FLG(inode, MS_NOEXEC)
158 #define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || ((inode)->i_flags & S_SYNC))
159 #define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
161 #define IS_QUOTAINIT(inode) ((inode)->i_flags & S_QUOTA)
162 #define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
163 #define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
164 #define IS_NOATIME(inode) (__IS_FLG(inode, MS_NOATIME) || ((inode)->i_flags & S_NOATIME))
165 #define IS_NODIRATIME(inode) __IS_FLG(inode, MS_NODIRATIME)
167 #define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
169 /* the read-only stuff doesn't really belong here, but any other place is
170 probably as bad and I don't want to create yet another include file. */
172 #define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
173 #define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
174 #define BLKRRPART _IO(0x12,95) /* re-read partition table */
175 #define BLKGETSIZE _IO(0x12,96) /* return device size */
176 #define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
177 #define BLKRASET _IO(0x12,98) /* Set read ahead for block device */
178 #define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
179 #define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
180 #define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
181 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
182 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
183 #define BLKSSZGET _IO(0x12,104)/* get block device sector size */
185 #define BLKPG _IO(0x12,105)/* See blkpg.h */
186 #define BLKELVGET _IOR(0x12,106,sizeof(blkelv_ioctl_arg_t))/* elevator get */
187 #define BLKELVSET _IOW(0x12,107,sizeof(blkelv_ioctl_arg_t))/* elevator set */
188 /* This was here just to show that the number is taken -
189 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
193 #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
194 #define FIBMAP _IO(0x00,1) /* bmap access */
195 #define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
199 #include <asm/semaphore.h>
200 #include <asm/byteorder.h>
202 extern void update_atime (struct inode *);
203 #define UPDATE_ATIME(inode) update_atime (inode)
205 extern void buffer_init(unsigned long);
206 extern void inode_init(unsigned long);
209 #define BH_Uptodate 0 /* 1 if the buffer contains valid data */
210 #define BH_Dirty 1 /* 1 if the buffer is dirty */
211 #define BH_Lock 2 /* 1 if the buffer is locked */
212 #define BH_Req 3 /* 0 if the buffer has been invalidated */
213 #define BH_Mapped 4 /* 1 if the buffer has a disk mapping */
214 #define BH_New 5 /* 1 if the buffer is new and not yet written out */
215 #define BH_Protected 6 /* 1 if the buffer is protected */
218 * Try to keep the most commonly used fields in single cache lines (16
219 * bytes) to improve performance. This ordering should be
220 * particularly beneficial on 32-bit processors.
222 * We use the first 16 bytes for the data which is used in searches
223 * over the block hash lists (ie. getblk() and friends).
225 * The second 16 bytes we use for lru buffer scans, as used by
226 * sync_buffers() and refill_freelist(). -- sct
229 /* First cache line: */
230 struct buffer_head *b_next; /* Hash queue list */
231 unsigned long b_blocknr; /* block number */
232 unsigned short b_size; /* block size */
233 unsigned short b_list; /* List that this buffer appears */
234 kdev_t b_dev; /* device (B_FREE = free) */
236 atomic_t b_count; /* users using this block */
237 kdev_t b_rdev; /* Real device */
238 unsigned long b_state; /* buffer state bitmap (see above) */
239 unsigned long b_flushtime; /* Time when (dirty) buffer should be written */
241 struct buffer_head *b_next_free;/* lru/free list linkage */
242 struct buffer_head *b_prev_free;/* doubly linked list of buffers */
243 struct buffer_head *b_this_page;/* circular list of buffers in one page */
244 struct buffer_head *b_reqnext; /* request queue */
246 struct buffer_head **b_pprev; /* doubly linked list of hash-queue */
247 char * b_data; /* pointer to data block */
248 struct page *b_page; /* the page this bh is mapped to */
249 void (*b_end_io)(struct buffer_head *bh, int uptodate); /* I/O completion */
250 void *b_private; /* reserved for b_end_io */
252 unsigned long b_rsector; /* Real buffer location on disk */
253 wait_queue_head_t b_wait;
255 struct inode * b_inode;
256 struct list_head b_inode_buffers; /* doubly linked list of inode dirty buffers */
259 typedef void (bh_end_io_t)(struct buffer_head *bh, int uptodate);
260 void init_buffer(struct buffer_head *, bh_end_io_t *, void *);
262 #define __buffer_state(bh, state) (((bh)->b_state & (1UL << BH_##state)) != 0)
264 #define buffer_uptodate(bh) __buffer_state(bh,Uptodate)
265 #define buffer_dirty(bh) __buffer_state(bh,Dirty)
266 #define buffer_locked(bh) __buffer_state(bh,Lock)
267 #define buffer_req(bh) __buffer_state(bh,Req)
268 #define buffer_mapped(bh) __buffer_state(bh,Mapped)
269 #define buffer_new(bh) __buffer_state(bh,New)
270 #define buffer_protected(bh) __buffer_state(bh,Protected)
272 #define bh_offset(bh) ((unsigned long)(bh)->b_data & ~PAGE_MASK)
274 extern void set_bh_page(struct buffer_head *bh, struct page *page, unsigned long offset);
276 #define touch_buffer(bh) SetPageReferenced(bh->b_page)
279 #include <linux/pipe_fs_i.h>
280 #include <linux/minix_fs_i.h>
281 #include <linux/ext2_fs_i.h>
282 #include <linux/hpfs_fs_i.h>
283 #include <linux/ntfs_fs_i.h>
284 #include <linux/msdos_fs_i.h>
285 #include <linux/umsdos_fs_i.h>
286 #include <linux/iso_fs_i.h>
287 #include <linux/nfs_fs_i.h>
288 #include <linux/sysv_fs_i.h>
289 #include <linux/affs_fs_i.h>
290 #include <linux/ufs_fs_i.h>
291 #include <linux/efs_fs_i.h>
292 #include <linux/coda_fs_i.h>
293 #include <linux/romfs_fs_i.h>
294 #include <linux/shmem_fs.h>
295 #include <linux/smb_fs_i.h>
296 #include <linux/hfs_fs_i.h>
297 #include <linux/adfs_fs_i.h>
298 #include <linux/qnx4_fs_i.h>
299 #include <linux/reiserfs_fs_i.h>
300 #include <linux/bfs_fs_i.h>
301 #include <linux/udf_fs_i.h>
302 #include <linux/ncp_fs_i.h>
303 #include <linux/proc_fs_i.h>
304 #include <linux/usbdev_fs_i.h>
307 * Attribute flags. These should be or-ed together to figure out what
314 #define ATTR_ATIME 16
315 #define ATTR_MTIME 32
316 #define ATTR_CTIME 64
317 #define ATTR_ATIME_SET 128
318 #define ATTR_MTIME_SET 256
319 #define ATTR_FORCE 512 /* Not a change, but a change it */
320 #define ATTR_ATTR_FLAG 1024
323 * This is the Inode Attributes structure, used for notify_change(). It
324 * uses the above definitions as flags, to know which values have changed.
325 * Also, in this manner, a Filesystem can look at only the values it cares
326 * about. Basically, these are the attributes that the VFS layer can
327 * request to change from the FS layer.
329 * Derek Atkins <warlord@MIT.EDU> 94-10-20
332 unsigned int ia_valid;
340 unsigned int ia_attr_flags;
344 * This is the inode attributes flag definitions
346 #define ATTR_FLAG_SYNCRONOUS 1 /* Syncronous write */
347 #define ATTR_FLAG_NOATIME 2 /* Don't update atime */
348 #define ATTR_FLAG_APPEND 4 /* Append-only file */
349 #define ATTR_FLAG_IMMUTABLE 8 /* Immutable file */
350 #define ATTR_FLAG_NODIRATIME 16 /* Don't update atime for directory */
353 * Includes for diskquotas and mount structures.
355 #include <linux/quota.h>
356 #include <linux/mount.h>
359 * oh the beauties of C type declarations.
362 struct address_space;
364 struct address_space_operations {
365 int (*writepage)(struct page *);
366 int (*readpage)(struct file *, struct page *);
367 int (*sync_page)(struct page *);
368 int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
369 int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
370 /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
371 int (*bmap)(struct address_space *, long);
374 struct address_space {
375 struct list_head clean_pages; /* list of clean pages */
376 struct list_head dirty_pages; /* list of dirty pages */
377 struct list_head locked_pages; /* list of locked pages */
378 unsigned long nrpages; /* number of total pages */
379 struct address_space_operations *a_ops; /* methods */
380 struct inode *host; /* owner: inode, block_device */
381 struct vm_area_struct *i_mmap; /* list of private mappings */
382 struct vm_area_struct *i_mmap_shared; /* list of shared mappings */
383 spinlock_t i_shared_lock; /* and spinlock protecting it */
384 int gfp_mask; /* how to allocate the pages */
388 struct list_head hash;
392 struct semaphore sem;
395 struct block_device {
396 struct list_head bd_hash;
398 /* struct address_space bd_data; */
399 dev_t bd_dev; /* not a kdev_t - it's a search key */
401 const struct block_device_operations *bd_op;
402 struct semaphore bd_sem; /* open/close mutex */
406 struct list_head i_hash;
407 struct list_head i_list;
408 struct list_head i_dentry;
410 struct list_head i_dirty_buffers;
424 unsigned long i_blksize;
425 unsigned long i_blocks;
426 unsigned long i_version;
427 struct semaphore i_sem;
428 struct semaphore i_zombie;
429 struct inode_operations *i_op;
430 struct file_operations *i_fop; /* former ->i_op->default_file_ops */
431 struct super_block *i_sb;
432 wait_queue_head_t i_wait;
433 struct file_lock *i_flock;
434 struct address_space *i_mapping;
435 struct address_space i_data;
436 struct dquot *i_dquot[MAXQUOTAS];
437 /* These three should probably be a union */
438 struct pipe_inode_info *i_pipe;
439 struct block_device *i_bdev;
440 struct char_device *i_cdev;
442 unsigned long i_dnotify_mask; /* Directory notify events */
443 struct dnotify_struct *i_dnotify; /* for directory notifications */
445 unsigned long i_state;
447 unsigned int i_flags;
448 unsigned char i_sock;
450 atomic_t i_writecount;
451 unsigned int i_attr_flags;
454 struct minix_inode_info minix_i;
455 struct ext2_inode_info ext2_i;
456 struct hpfs_inode_info hpfs_i;
457 struct ntfs_inode_info ntfs_i;
458 struct msdos_inode_info msdos_i;
459 struct umsdos_inode_info umsdos_i;
460 struct iso_inode_info isofs_i;
461 struct nfs_inode_info nfs_i;
462 struct sysv_inode_info sysv_i;
463 struct affs_inode_info affs_i;
464 struct ufs_inode_info ufs_i;
465 struct efs_inode_info efs_i;
466 struct romfs_inode_info romfs_i;
467 struct shmem_inode_info shmem_i;
468 struct coda_inode_info coda_i;
469 struct smb_inode_info smbfs_i;
470 struct hfs_inode_info hfs_i;
471 struct adfs_inode_info adfs_i;
472 struct qnx4_inode_info qnx4_i;
473 struct reiserfs_inode_info reiserfs_i;
474 struct bfs_inode_info bfs_i;
475 struct udf_inode_info udf_i;
476 struct ncp_inode_info ncpfs_i;
477 struct proc_inode_info proc_i;
478 struct socket socket_i;
479 struct usbdev_inode_info usbdev_i;
485 int pid; /* pid or -pgrp where SIGIO should be sent */
486 uid_t uid, euid; /* uid/euid of process setting the owner */
487 int signum; /* posix.1b rt signal to be delivered on IO */
491 struct list_head f_list;
492 struct dentry *f_dentry;
493 struct vfsmount *f_vfsmnt;
494 struct file_operations *f_op;
496 unsigned int f_flags;
499 unsigned long f_reada, f_ramax, f_raend, f_ralen, f_rawin;
500 struct fown_struct f_owner;
501 unsigned int f_uid, f_gid;
504 unsigned long f_version;
506 /* needed for tty driver, and maybe others */
509 extern spinlock_t files_lock;
510 #define file_list_lock() spin_lock(&files_lock);
511 #define file_list_unlock() spin_unlock(&files_lock);
513 #define get_file(x) atomic_inc(&(x)->f_count)
514 #define file_count(x) atomic_read(&(x)->f_count)
516 extern int init_private_file(struct file *, struct dentry *, int);
518 #define MAX_NON_LFS ((1UL<<31) - 1)
522 #define FL_BROKEN 4 /* broken flock() emulation */
523 #define FL_ACCESS 8 /* for processes suspended by mandatory locking */
524 #define FL_LOCKD 16 /* lock held by rpc.lockd */
525 #define FL_LEASE 32 /* lease held on this file */
528 * The POSIX file lock owner is determined by
529 * the "struct files_struct" in the thread group
530 * (or NULL for no owner - BSD locks).
532 * Lockd stuffs a "host" pointer into this.
534 typedef struct files_struct *fl_owner_t;
537 struct file_lock *fl_next; /* singly linked list for this inode */
538 struct list_head fl_link; /* doubly linked list of all locks */
539 struct list_head fl_block; /* circular list of blocked processes */
542 wait_queue_head_t fl_wait;
543 struct file *fl_file;
544 unsigned char fl_flags;
545 unsigned char fl_type;
549 void (*fl_notify)(struct file_lock *); /* unblock callback */
550 void (*fl_insert)(struct file_lock *); /* lock insertion callback */
551 void (*fl_remove)(struct file_lock *); /* lock removal callback */
553 struct fasync_struct * fl_fasync; /* for lease break notifications */
556 struct nfs_lock_info nfs_fl;
560 /* The following constant reflects the upper bound of the file/locking space */
562 #define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
563 #define OFFSET_MAX INT_LIMIT(loff_t)
564 #define OFFT_OFFSET_MAX INT_LIMIT(off_t)
567 extern struct list_head file_lock_list;
569 #include <linux/fcntl.h>
571 extern int fcntl_getlk(unsigned int, struct flock *);
572 extern int fcntl_setlk(unsigned int, unsigned int, struct flock *);
574 extern int fcntl_getlk64(unsigned int, struct flock64 *);
575 extern int fcntl_setlk64(unsigned int, unsigned int, struct flock64 *);
578 extern void locks_init_lock(struct file_lock *);
579 extern void locks_copy_lock(struct file_lock *, struct file_lock *);
580 extern void locks_remove_posix(struct file *, fl_owner_t);
581 extern void locks_remove_flock(struct file *);
582 extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
583 extern int posix_lock_file(struct file *, struct file_lock *, unsigned int);
584 extern void posix_block_lock(struct file_lock *, struct file_lock *);
585 extern void posix_unblock_lock(struct file_lock *);
586 extern int __get_lease(struct inode *inode, unsigned int flags);
587 extern time_t lease_get_mtime(struct inode *);
588 extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
589 extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
591 struct fasync_struct {
594 struct fasync_struct *fa_next; /* singly linked list */
595 struct file *fa_file;
598 #define FASYNC_MAGIC 0x4601
600 /* SMP safe fasync helpers: */
601 extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
602 /* can be called from interrupts */
603 extern void kill_fasync(struct fasync_struct **, int, int);
604 /* only for net: no internal synchronization */
605 extern void __kill_fasync(struct fasync_struct *, int, int);
608 struct dentry *dentry;
609 struct vfsmount *mnt;
615 #define DQUOT_USR_ENABLED 0x01 /* User diskquotas enabled */
616 #define DQUOT_GRP_ENABLED 0x02 /* Group diskquotas enabled */
618 struct quota_mount_options
620 unsigned int flags; /* Flags for diskquotas on this device */
621 struct semaphore dqio_sem; /* lock device while I/O in progress */
622 struct semaphore dqoff_sem; /* serialize quota_off() and quota_on() on device */
623 struct file *files[MAXQUOTAS]; /* fp's to quotafiles */
624 time_t inode_expire[MAXQUOTAS]; /* expiretime for inode-quota */
625 time_t block_expire[MAXQUOTAS]; /* expiretime for block-quota */
626 char rsquash[MAXQUOTAS]; /* for quotas threat root as any other user */
633 #define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
635 #include <linux/minix_fs_sb.h>
636 #include <linux/ext2_fs_sb.h>
637 #include <linux/hpfs_fs_sb.h>
638 #include <linux/ntfs_fs_sb.h>
639 #include <linux/msdos_fs_sb.h>
640 #include <linux/iso_fs_sb.h>
641 #include <linux/nfs_fs_sb.h>
642 #include <linux/sysv_fs_sb.h>
643 #include <linux/affs_fs_sb.h>
644 #include <linux/ufs_fs_sb.h>
645 #include <linux/efs_fs_sb.h>
646 #include <linux/romfs_fs_sb.h>
647 #include <linux/smb_fs_sb.h>
648 #include <linux/hfs_fs_sb.h>
649 #include <linux/adfs_fs_sb.h>
650 #include <linux/qnx4_fs_sb.h>
651 #include <linux/reiserfs_fs_sb.h>
652 #include <linux/bfs_fs_sb.h>
653 #include <linux/udf_fs_sb.h>
654 #include <linux/ncp_fs_sb.h>
655 #include <linux/usbdev_fs_sb.h>
657 extern struct list_head super_blocks;
659 #define sb_entry(list) list_entry((list), struct super_block, s_list)
661 struct list_head s_list; /* Keep this first */
663 unsigned long s_blocksize;
664 unsigned char s_blocksize_bits;
665 unsigned char s_dirt;
666 unsigned long long s_maxbytes; /* Max file size */
667 struct file_system_type *s_type;
668 struct super_operations *s_op;
669 struct dquot_operations *dq_op;
670 unsigned long s_flags;
671 unsigned long s_magic;
672 struct dentry *s_root;
673 struct rw_semaphore s_umount;
674 struct semaphore s_lock;
676 struct list_head s_dirty; /* dirty inodes */
677 struct list_head s_locked_inodes;/* inodes being synced */
678 struct list_head s_files;
680 struct block_device *s_bdev;
681 struct list_head s_mounts; /* vfsmount(s) of this one */
682 struct quota_mount_options s_dquot; /* Diskquota specific options */
685 struct minix_sb_info minix_sb;
686 struct ext2_sb_info ext2_sb;
687 struct hpfs_sb_info hpfs_sb;
688 struct ntfs_sb_info ntfs_sb;
689 struct msdos_sb_info msdos_sb;
690 struct isofs_sb_info isofs_sb;
691 struct nfs_sb_info nfs_sb;
692 struct sysv_sb_info sysv_sb;
693 struct affs_sb_info affs_sb;
694 struct ufs_sb_info ufs_sb;
695 struct efs_sb_info efs_sb;
696 struct shmem_sb_info shmem_sb;
697 struct romfs_sb_info romfs_sb;
698 struct smb_sb_info smbfs_sb;
699 struct hfs_sb_info hfs_sb;
700 struct adfs_sb_info adfs_sb;
701 struct qnx4_sb_info qnx4_sb;
702 struct reiserfs_sb_info reiserfs_sb;
703 struct bfs_sb_info bfs_sb;
704 struct udf_sb_info udf_sb;
705 struct ncp_sb_info ncpfs_sb;
706 struct usbdev_sb_info usbdevfs_sb;
710 * The next field is for VFS *only*. No filesystems have any business
711 * even looking at it. You had been warned.
713 struct semaphore s_vfs_rename_sem; /* Kludge */
715 /* The next field is used by knfsd when converting a (inode number based)
716 * file handle into a dentry. As it builds a path in the dcache tree from
717 * the bottom up, there may for a time be a subpath of dentrys which is not
718 * connected to the main tree. This semaphore ensure that there is only ever
719 * one such free path per filesystem. Note that unconnected files (or other
720 * non-directories) are allowed, but not unconnected diretories.
722 struct semaphore s_nfsd_free_path_sem;
726 * VFS helper functions..
728 extern int vfs_create(struct inode *, struct dentry *, int);
729 extern int vfs_mkdir(struct inode *, struct dentry *, int);
730 extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
731 extern int vfs_symlink(struct inode *, struct dentry *, const char *);
732 extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
733 extern int vfs_rmdir(struct inode *, struct dentry *);
734 extern int vfs_unlink(struct inode *, struct dentry *);
735 extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
751 * This is the "filldir" function type, used by readdir() to let
752 * the kernel specify what kind of dirent layout it wants to have.
753 * This allows the kernel to read directories into kernel space or
754 * to have different dirent layouts depending on the binary type.
756 typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t, unsigned);
758 struct block_device_operations {
759 int (*open) (struct inode *, struct file *);
760 int (*release) (struct inode *, struct file *);
761 int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
762 int (*check_media_change) (kdev_t);
763 int (*revalidate) (kdev_t);
768 * read, write, poll, fsync, readv, writev can be called
769 * without the big kernel lock held in all filesystems.
771 struct file_operations {
772 struct module *owner;
773 loff_t (*llseek) (struct file *, loff_t, int);
774 ssize_t (*read) (struct file *, char *, size_t, loff_t *);
775 ssize_t (*write) (struct file *, const char *, size_t, loff_t *);
776 int (*readdir) (struct file *, void *, filldir_t);
777 unsigned int (*poll) (struct file *, struct poll_table_struct *);
778 int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
779 int (*mmap) (struct file *, struct vm_area_struct *);
780 int (*open) (struct inode *, struct file *);
781 int (*flush) (struct file *);
782 int (*release) (struct inode *, struct file *);
783 int (*fsync) (struct file *, struct dentry *, int datasync);
784 int (*fasync) (int, struct file *, int);
785 int (*lock) (struct file *, int, struct file_lock *);
786 ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *);
787 ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *);
788 ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
789 unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
792 struct inode_operations {
793 int (*create) (struct inode *,struct dentry *,int);
794 struct dentry * (*lookup) (struct inode *,struct dentry *);
795 int (*link) (struct dentry *,struct inode *,struct dentry *);
796 int (*unlink) (struct inode *,struct dentry *);
797 int (*symlink) (struct inode *,struct dentry *,const char *);
798 int (*mkdir) (struct inode *,struct dentry *,int);
799 int (*rmdir) (struct inode *,struct dentry *);
800 int (*mknod) (struct inode *,struct dentry *,int,int);
801 int (*rename) (struct inode *, struct dentry *,
802 struct inode *, struct dentry *);
803 int (*readlink) (struct dentry *, char *,int);
804 int (*follow_link) (struct dentry *, struct nameidata *);
805 void (*truncate) (struct inode *);
806 int (*permission) (struct inode *, int);
807 int (*revalidate) (struct dentry *);
808 int (*setattr) (struct dentry *, struct iattr *);
809 int (*getattr) (struct dentry *, struct iattr *);
813 * NOTE: write_inode, delete_inode, clear_inode, put_inode can be called
814 * without the big kernel lock held in all filesystems.
816 struct super_operations {
817 void (*read_inode) (struct inode *);
819 /* reiserfs kludge. reiserfs needs 64 bits of information to
820 ** find an inode. We are using the read_inode2 call to get
821 ** that information. We don't like this, and are waiting on some
822 ** VFS changes for the real solution.
823 ** iget4 calls read_inode2, iff it is defined
825 void (*read_inode2) (struct inode *, void *) ;
826 void (*dirty_inode) (struct inode *);
827 void (*write_inode) (struct inode *, int);
828 void (*put_inode) (struct inode *);
829 void (*delete_inode) (struct inode *);
830 void (*put_super) (struct super_block *);
831 void (*write_super) (struct super_block *);
832 void (*write_super_lockfs) (struct super_block *);
833 void (*unlockfs) (struct super_block *);
834 int (*statfs) (struct super_block *, struct statfs *);
835 int (*remount_fs) (struct super_block *, int *, char *);
836 void (*clear_inode) (struct inode *);
837 void (*umount_begin) (struct super_block *);
840 /* Inode state bits.. */
841 #define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */
842 #define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */
843 #define I_DIRTY_PAGES 4 /* Data-related inode changes pending */
848 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
850 extern void __mark_inode_dirty(struct inode *, int);
851 static inline void mark_inode_dirty(struct inode *inode)
853 __mark_inode_dirty(inode, I_DIRTY);
856 static inline void mark_inode_dirty_sync(struct inode *inode)
858 __mark_inode_dirty(inode, I_DIRTY_SYNC);
861 static inline void mark_inode_dirty_pages(struct inode *inode)
863 __mark_inode_dirty(inode, I_DIRTY_PAGES);
866 struct dquot_operations {
867 void (*initialize) (struct inode *, short);
868 void (*drop) (struct inode *);
869 int (*alloc_block) (const struct inode *, unsigned long, char);
870 int (*alloc_inode) (const struct inode *, unsigned long);
871 void (*free_block) (const struct inode *, unsigned long);
872 void (*free_inode) (const struct inode *, unsigned long);
873 int (*transfer) (struct dentry *, struct iattr *);
876 struct file_system_type {
879 struct super_block *(*read_super) (struct super_block *, void *, int);
880 struct module *owner;
881 struct vfsmount *kern_mnt; /* For kernel mount, if it's FS_SINGLE fs */
882 struct file_system_type * next;
885 #define DECLARE_FSTYPE(var,type,read,flags) \
886 struct file_system_type var = { \
890 owner: THIS_MODULE, \
893 #define DECLARE_FSTYPE_DEV(var,type,read) \
894 DECLARE_FSTYPE(var,type,read,FS_REQUIRES_DEV)
896 /* Alas, no aliases. Too much hassle with bringing module.h everywhere */
897 #define fops_get(fops) \
898 (((fops) && (fops)->owner) \
899 ? ( try_inc_mod_count((fops)->owner) ? (fops) : NULL ) \
902 #define fops_put(fops) \
904 if ((fops) && (fops)->owner) \
905 __MOD_DEC_USE_COUNT((fops)->owner); \
908 extern int register_filesystem(struct file_system_type *);
909 extern int unregister_filesystem(struct file_system_type *);
910 extern struct vfsmount *kern_mount(struct file_system_type *);
911 extern int may_umount(struct vfsmount *);
912 extern long do_mount(char *, char *, char *, unsigned long, void *);
914 #define kern_umount mntput
916 extern int vfs_statfs(struct super_block *, struct statfs *);
918 /* Return value for VFS lock functions - tells locks.c to lock conventionally
919 * REALLY kosha for root NFS and nfs_lock
921 #define LOCK_USE_CLNT 1
923 #define FLOCK_VERIFY_READ 1
924 #define FLOCK_VERIFY_WRITE 2
926 extern int locks_mandatory_locked(struct inode *);
927 extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
930 * Candidates for mandatory locking have the setgid bit set
931 * but no group execute bit - an otherwise meaningless combination.
933 #define MANDATORY_LOCK(inode) \
934 (IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
936 static inline int locks_verify_locked(struct inode *inode)
938 if (MANDATORY_LOCK(inode))
939 return locks_mandatory_locked(inode);
943 static inline int locks_verify_area(int read_write, struct inode *inode,
944 struct file *filp, loff_t offset,
947 if (inode->i_flock && MANDATORY_LOCK(inode))
948 return locks_mandatory_area(read_write, inode, filp, offset, count);
952 static inline int locks_verify_truncate(struct inode *inode,
956 if (inode->i_flock && MANDATORY_LOCK(inode))
957 return locks_mandatory_area(
958 FLOCK_VERIFY_WRITE, inode, filp,
959 size < inode->i_size ? size : inode->i_size,
960 (size < inode->i_size ? inode->i_size - size
961 : size - inode->i_size)
966 extern inline int get_lease(struct inode *inode, unsigned int mode)
968 if (inode->i_flock && (inode->i_flock->fl_flags & FL_LEASE))
969 return __get_lease(inode, mode);
975 asmlinkage long sys_open(const char *, int, int);
976 asmlinkage long sys_close(unsigned int); /* yes, it's really unsigned */
977 extern int do_truncate(struct dentry *, loff_t start);
979 extern struct file *filp_open(const char *, int, int);
980 extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
981 extern int filp_close(struct file *, fl_owner_t id);
982 extern char * getname(const char *);
985 extern void vfs_caches_init(unsigned long);
987 #define __getname() kmem_cache_alloc(names_cachep, SLAB_KERNEL)
988 #define putname(name) kmem_cache_free(names_cachep, (void *)(name))
990 enum {BDEV_FILE, BDEV_SWAP, BDEV_FS, BDEV_RAW};
991 extern int register_blkdev(unsigned int, const char *, struct block_device_operations *);
992 extern int unregister_blkdev(unsigned int, const char *);
993 extern struct block_device *bdget(dev_t);
994 extern void bdput(struct block_device *);
995 extern struct char_device *cdget(dev_t);
996 extern void cdput(struct char_device *);
997 extern int blkdev_open(struct inode *, struct file *);
998 extern struct file_operations def_blk_fops;
999 extern struct file_operations def_fifo_fops;
1000 extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
1001 extern int blkdev_get(struct block_device *, mode_t, unsigned, int);
1002 extern int blkdev_put(struct block_device *, int);
1005 extern const struct block_device_operations *get_blkfops(unsigned int);
1006 extern int register_chrdev(unsigned int, const char *, struct file_operations *);
1007 extern int unregister_chrdev(unsigned int, const char *);
1008 extern int chrdev_open(struct inode *, struct file *);
1009 extern const char * bdevname(kdev_t);
1010 extern const char * cdevname(kdev_t);
1011 extern const char * kdevname(kdev_t);
1012 extern void init_special_inode(struct inode *, umode_t, int);
1014 /* Invalid inode operations -- fs/bad_inode.c */
1015 extern void make_bad_inode(struct inode *);
1016 extern int is_bad_inode(struct inode *);
1018 extern struct file_operations read_fifo_fops;
1019 extern struct file_operations write_fifo_fops;
1020 extern struct file_operations rdwr_fifo_fops;
1021 extern struct file_operations read_pipe_fops;
1022 extern struct file_operations write_pipe_fops;
1023 extern struct file_operations rdwr_pipe_fops;
1025 extern int fs_may_remount_ro(struct super_block *);
1027 extern int try_to_free_buffers(struct page *, int);
1028 extern void refile_buffer(struct buffer_head * buf);
1030 /* reiserfs_writepage needs this */
1031 extern void set_buffer_async_io(struct buffer_head *bh) ;
1034 #define BUF_LOCKED 1 /* Buffers scheduled for write */
1035 #define BUF_DIRTY 2 /* Dirty buffers, not yet scheduled for write */
1036 #define BUF_PROTECTED 3 /* Ramdisk persistent storage */
1040 * This is called by bh->b_end_io() handlers when I/O has completed.
1042 static inline void mark_buffer_uptodate(struct buffer_head * bh, int on)
1045 set_bit(BH_Uptodate, &bh->b_state);
1047 clear_bit(BH_Uptodate, &bh->b_state);
1050 #define atomic_set_buffer_clean(bh) test_and_clear_bit(BH_Dirty, &(bh)->b_state)
1052 static inline void __mark_buffer_clean(struct buffer_head *bh)
1057 static inline void mark_buffer_clean(struct buffer_head * bh)
1059 if (atomic_set_buffer_clean(bh))
1060 __mark_buffer_clean(bh);
1063 #define atomic_set_buffer_protected(bh) test_and_set_bit(BH_Protected, &(bh)->b_state)
1065 static inline void __mark_buffer_protected(struct buffer_head *bh)
1070 static inline void mark_buffer_protected(struct buffer_head * bh)
1072 if (!atomic_set_buffer_protected(bh))
1073 __mark_buffer_protected(bh);
1076 extern void FASTCALL(__mark_buffer_dirty(struct buffer_head *bh));
1077 extern void FASTCALL(mark_buffer_dirty(struct buffer_head *bh));
1079 #define atomic_set_buffer_dirty(bh) test_and_set_bit(BH_Dirty, &(bh)->b_state)
1082 * If an error happens during the make_request, this function
1083 * has to be recalled. It marks the buffer as clean and not
1084 * uptodate, and it notifys the upper layer about the end
1087 static inline void buffer_IO_error(struct buffer_head * bh)
1089 mark_buffer_clean(bh);
1091 * b_end_io has to clear the BH_Uptodate bitflag in the error case!
1093 bh->b_end_io(bh, 0);
1096 extern void buffer_insert_inode_queue(struct buffer_head *, struct inode *);
1097 static inline void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode)
1099 mark_buffer_dirty(bh);
1100 buffer_insert_inode_queue(bh, inode);
1103 extern void balance_dirty(kdev_t);
1104 extern int check_disk_change(kdev_t);
1105 extern int invalidate_inodes(struct super_block *);
1106 extern int invalidate_device(kdev_t, int);
1107 extern void invalidate_inode_pages(struct inode *);
1108 extern void invalidate_inode_buffers(struct inode *);
1109 #define invalidate_buffers(dev) __invalidate_buffers((dev), 0)
1110 #define destroy_buffers(dev) __invalidate_buffers((dev), 1)
1111 extern void __invalidate_buffers(kdev_t dev, int);
1112 extern void sync_inodes(kdev_t);
1113 extern void sync_unlocked_inodes(void);
1114 extern void write_inode_now(struct inode *, int);
1115 extern void sync_dev(kdev_t);
1116 extern int fsync_dev(kdev_t);
1117 extern int fsync_super(struct super_block *);
1118 extern void sync_inodes_sb(struct super_block *);
1119 extern int fsync_inode_buffers(struct inode *);
1120 extern int osync_inode_buffers(struct inode *);
1121 extern int inode_has_buffers(struct inode *);
1122 extern void filemap_fdatasync(struct address_space *);
1123 extern void filemap_fdatawait(struct address_space *);
1124 extern void sync_supers(kdev_t);
1125 extern int bmap(struct inode *, int);
1126 extern int notify_change(struct dentry *, struct iattr *);
1127 extern int permission(struct inode *, int);
1128 extern int vfs_permission(struct inode *, int);
1129 extern int get_write_access(struct inode *);
1130 extern int deny_write_access(struct file *);
1131 static inline void put_write_access(struct inode * inode)
1133 atomic_dec(&inode->i_writecount);
1135 static inline void allow_write_access(struct file *file)
1138 atomic_inc(&file->f_dentry->d_inode->i_writecount);
1140 extern int do_pipe(int *);
1142 extern int open_namei(const char *, int, int, struct nameidata *);
1144 extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
1145 extern struct file * open_exec(const char *);
1147 /* fs/dcache.c -- generic fs support functions */
1148 extern int is_subdir(struct dentry *, struct dentry *);
1149 extern ino_t find_inode_number(struct dentry *, struct qstr *);
1152 * Kernel pointers have redundant information, so we can use a
1153 * scheme where we can return either an error code or a dentry
1154 * pointer with the same return value.
1156 * This should be a per-architecture thing, to allow different
1157 * error and pointer decisions.
1159 static inline void *ERR_PTR(long error)
1161 return (void *) error;
1164 static inline long PTR_ERR(const void *ptr)
1169 static inline long IS_ERR(const void *ptr)
1171 return (unsigned long)ptr > (unsigned long)-1000L;
1175 * The bitmask for a lookup event:
1176 * - follow links at the end
1177 * - require a directory
1178 * - ending slashes ok even for nonexistent files
1179 * - internal "there are more path compnents" flag
1181 #define LOOKUP_FOLLOW (1)
1182 #define LOOKUP_DIRECTORY (2)
1183 #define LOOKUP_CONTINUE (4)
1184 #define LOOKUP_POSITIVE (8)
1185 #define LOOKUP_PARENT (16)
1186 #define LOOKUP_NOALT (32)
1188 * Type of the last component on LOOKUP_PARENT
1190 enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
1193 * "descriptor" for what we're up to with a read for sendfile().
1194 * This allows us to use the same read code yet
1195 * have multiple different users of the data that
1196 * we read from a file.
1198 * The simplest case just copies the data to user
1206 } read_descriptor_t;
1208 typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long);
1210 /* needed for stackable file system support */
1211 extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
1213 extern int __user_walk(const char *, unsigned, struct nameidata *);
1214 extern int path_init(const char *, unsigned, struct nameidata *);
1215 extern int path_walk(const char *, struct nameidata *);
1216 extern void path_release(struct nameidata *);
1217 extern int follow_down(struct vfsmount **, struct dentry **);
1218 extern int follow_up(struct vfsmount **, struct dentry **);
1219 extern struct dentry * lookup_one_len(const char *, struct dentry *, int);
1220 extern struct dentry * lookup_hash(struct qstr *, struct dentry *);
1221 #define user_path_walk(name,nd) __user_walk(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, nd)
1222 #define user_path_walk_link(name,nd) __user_walk(name, LOOKUP_POSITIVE, nd)
1224 extern void iput(struct inode *);
1225 extern void force_delete(struct inode *);
1226 extern struct inode * igrab(struct inode *);
1227 extern ino_t iunique(struct super_block *, ino_t);
1229 typedef int (*find_inode_t)(struct inode *, unsigned long, void *);
1230 extern struct inode * iget4(struct super_block *, unsigned long, find_inode_t, void *);
1231 static inline struct inode *iget(struct super_block *sb, unsigned long ino)
1233 return iget4(sb, ino, NULL, NULL);
1236 extern void clear_inode(struct inode *);
1237 extern struct inode * get_empty_inode(void);
1238 static inline struct inode * new_inode(struct super_block *sb)
1240 struct inode *inode = get_empty_inode();
1243 inode->i_dev = sb->s_dev;
1247 extern void remove_suid(struct inode *inode);
1249 extern void insert_inode_hash(struct inode *);
1250 extern void remove_inode_hash(struct inode *);
1251 extern struct file * get_empty_filp(void);
1252 extern void file_move(struct file *f, struct list_head *list);
1253 extern void file_moveto(struct file *new, struct file *old);
1254 extern struct buffer_head * get_hash_table(kdev_t, int, int);
1255 extern struct buffer_head * getblk(kdev_t, int, int);
1256 extern void ll_rw_block(int, int, struct buffer_head * bh[]);
1257 extern void submit_bh(int, struct buffer_head *);
1258 extern int is_read_only(kdev_t);
1259 extern void __brelse(struct buffer_head *);
1260 static inline void brelse(struct buffer_head *buf)
1265 extern void __bforget(struct buffer_head *);
1266 static inline void bforget(struct buffer_head *buf)
1271 extern void set_blocksize(kdev_t, int);
1272 extern struct buffer_head * bread(kdev_t, int, int);
1273 extern void wakeup_bdflush(int wait);
1275 extern int brw_page(int, struct page *, kdev_t, int [], int);
1277 typedef int (get_block_t)(struct inode*,long,struct buffer_head*,int);
1279 /* Generic buffer handling for block filesystems.. */
1280 extern int block_flushpage(struct page *, unsigned long);
1281 extern int block_symlink(struct inode *, const char *, int);
1282 extern int block_write_full_page(struct page*, get_block_t*);
1283 extern int block_read_full_page(struct page*, get_block_t*);
1284 extern int block_prepare_write(struct page*, unsigned, unsigned, get_block_t*);
1285 extern int cont_prepare_write(struct page*, unsigned, unsigned, get_block_t*,
1287 extern int block_sync_page(struct page *);
1289 int generic_block_bmap(struct address_space *, long, get_block_t *);
1290 int generic_commit_write(struct file *, struct page *, unsigned, unsigned);
1291 int block_truncate_page(struct address_space *, loff_t, get_block_t *);
1293 extern int waitfor_one_page(struct page*);
1294 extern int generic_file_mmap(struct file *, struct vm_area_struct *);
1295 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
1296 extern ssize_t generic_file_read(struct file *, char *, size_t, loff_t *);
1297 extern ssize_t generic_file_write(struct file *, const char *, size_t, loff_t *);
1298 extern void do_generic_file_read(struct file *, loff_t *, read_descriptor_t *, read_actor_t);
1300 extern ssize_t generic_read_dir(struct file *, char *, size_t, loff_t *);
1302 extern struct file_operations generic_ro_fops;
1304 extern int vfs_readlink(struct dentry *, char *, int, const char *);
1305 extern int vfs_follow_link(struct nameidata *, const char *);
1306 extern int page_readlink(struct dentry *, char *, int);
1307 extern int page_follow_link(struct dentry *, struct nameidata *);
1308 extern struct inode_operations page_symlink_inode_operations;
1310 extern int vfs_readdir(struct file *, filldir_t, void *);
1311 extern int dcache_readdir(struct file *, void *, filldir_t);
1313 extern struct file_system_type *get_fs_type(const char *name);
1314 extern struct super_block *get_super(kdev_t);
1315 extern void put_super(kdev_t);
1316 static inline int is_mounted(kdev_t dev)
1318 struct super_block *sb = get_super(dev);
1320 /* drop_super(sb); will go here */
1325 unsigned long generate_cluster(kdev_t, int b[], int);
1326 unsigned long generate_cluster_swab32(kdev_t, int b[], int);
1327 extern kdev_t ROOT_DEV;
1328 extern char root_device_name[];
1331 extern void show_buffers(void);
1332 extern void mount_root(void);
1334 #ifdef CONFIG_BLK_DEV_INITRD
1335 extern kdev_t real_root_dev;
1336 extern int change_root(kdev_t, const char *);
1339 extern ssize_t char_read(struct file *, char *, size_t, loff_t *);
1340 extern ssize_t block_read(struct file *, char *, size_t, loff_t *);
1341 extern int read_ahead[];
1343 extern ssize_t char_write(struct file *, const char *, size_t, loff_t *);
1344 extern ssize_t block_write(struct file *, const char *, size_t, loff_t *);
1346 extern int file_fsync(struct file *, struct dentry *, int);
1347 extern int generic_buffer_fdatasync(struct inode *inode, unsigned long start_idx, unsigned long end_idx);
1348 extern int generic_osync_inode(struct inode *, int);
1350 extern int inode_change_ok(struct inode *, struct iattr *);
1351 extern void inode_setattr(struct inode *, struct iattr *);
1354 * Common dentry functions for inclusion in the VFS
1355 * or in other stackable file systems. Some of these
1356 * functions were in linux/fs/ C (VFS) files.
1361 * Locking the parent is needed to:
1362 * - serialize directory operations
1363 * - make sure the parent doesn't change from
1364 * under us in the middle of an operation.
1366 * NOTE! Right now we'd rather use a "struct inode"
1367 * for this, but as I expect things to move toward
1368 * using dentries instead for most things it is
1369 * probably better to start with the conceptually
1370 * better interface of relying on a path of dentries.
1372 static inline struct dentry *lock_parent(struct dentry *dentry)
1374 struct dentry *dir = dget(dentry->d_parent);
1376 down(&dir->d_inode->i_sem);
1380 static inline struct dentry *get_parent(struct dentry *dentry)
1382 return dget(dentry->d_parent);
1385 static inline void unlock_dir(struct dentry *dir)
1387 up(&dir->d_inode->i_sem);
1392 * Whee.. Deadlock country. Happily there are only two VFS
1393 * operations that does this..
1395 static inline void double_down(struct semaphore *s1, struct semaphore *s2)
1398 if ((unsigned long) s1 < (unsigned long) s2) {
1399 struct semaphore *tmp = s2;
1408 * Ewwwwwwww... _triple_ lock. We are guaranteed that the 3rd argument is
1409 * not equal to 1st and not equal to 2nd - the first case (target is parent of
1410 * source) would be already caught, the second is plain impossible (target is
1411 * its own parent and that case would be caught even earlier). Very messy.
1412 * I _think_ that it works, but no warranties - please, look it through.
1413 * Pox on bloody lusers who mandated overwriting rename() for directories...
1416 static inline void triple_down(struct semaphore *s1,
1417 struct semaphore *s2,
1418 struct semaphore *s3)
1421 if ((unsigned long) s1 < (unsigned long) s2) {
1422 if ((unsigned long) s1 < (unsigned long) s3) {
1423 struct semaphore *tmp = s3;
1426 if ((unsigned long) s1 < (unsigned long) s2) {
1427 struct semaphore *tmp = s2;
1431 if ((unsigned long) s1 < (unsigned long) s3) {
1432 struct semaphore *tmp = s3;
1435 if ((unsigned long) s2 < (unsigned long) s3) {
1436 struct semaphore *tmp = s3;
1441 } else if ((unsigned long) s2 < (unsigned long) s3) {
1442 struct semaphore *tmp = s3;
1449 static inline void double_up(struct semaphore *s1, struct semaphore *s2)
1456 static inline void triple_up(struct semaphore *s1,
1457 struct semaphore *s2,
1458 struct semaphore *s3)
1466 static inline void double_lock(struct dentry *d1, struct dentry *d2)
1468 double_down(&d1->d_inode->i_sem, &d2->d_inode->i_sem);
1471 static inline void double_unlock(struct dentry *d1, struct dentry *d2)
1473 double_up(&d1->d_inode->i_sem,&d2->d_inode->i_sem);
1478 #endif /* __KERNEL__ */
1480 #endif /* _LINUX_FS_H */