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elilo/fs/fs.h

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#ifndef _LINUX_FS_H
#define _LINUX_FS_H
/*
* This file has definitions for some important file table
* structures etc.
*/
#include <linux/config.h>
#include <linux/linkage.h>
#include <linux/limits.h>
#include <linux/wait.h>
#include <linux/types.h>
#include <linux/vfs.h>
#include <linux/net.h>
#include <linux/kdev_t.h>
#include <linux/ioctl.h>
#include <linux/list.h>
#include <linux/dcache.h>
#include <linux/stat.h>
#include <linux/cache.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <asm/atomic.h>
#include <asm/bitops.h>
struct poll_table_struct;
/*
* It's silly to have NR_OPEN bigger than NR_FILE, but you can change
* the file limit at runtime and only root can increase the per-process
* nr_file rlimit, so it's safe to set up a ridiculously high absolute
* upper limit on files-per-process.
*
* Some programs (notably those using select()) may have to be
* recompiled to take full advantage of the new limits..
*/
/* Fixed constants first: */
#undef NR_OPEN
#define NR_OPEN (1024*1024) /* Absolute upper limit on fd num */
#define INR_OPEN 1024 /* Initial setting for nfile rlimits */
#define BLOCK_SIZE_BITS 10
#define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
/* And dynamically-tunable limits and defaults: */
struct files_stat_struct {
int nr_files; /* read only */
int nr_free_files; /* read only */
int max_files; /* tunable */
};
extern struct files_stat_struct files_stat;
struct inodes_stat_t {
int nr_inodes;
int nr_unused;
int dummy[5];
};
extern struct inodes_stat_t inodes_stat;
extern int max_super_blocks, nr_super_blocks;
extern int leases_enable, dir_notify_enable, lease_break_time;
#define NR_FILE 8192 /* this can well be larger on a larger system */
#define NR_RESERVED_FILES 10 /* reserved for root */
#define NR_SUPER 256
#define MAY_EXEC 1
#define MAY_WRITE 2
#define MAY_READ 4
#define FMODE_READ 1
#define FMODE_WRITE 2
#define READ 0
#define WRITE 1
#define READA 2 /* read-ahead - don't block if no resources */
#define SPECIAL 4 /* For non-blockdevice requests in request queue */
#define SEL_IN 1
#define SEL_OUT 2
#define SEL_EX 4
/* public flags for file_system_type */
#define FS_REQUIRES_DEV 1
#define FS_NO_DCACHE 2 /* Only dcache the necessary things. */
#define FS_NO_PRELIM 4 /* prevent preloading of dentries, even if
* FS_NO_DCACHE is not set.
*/
#define FS_SINGLE 8 /*
* Filesystem that can have only one superblock;
* kernel-wide vfsmnt is placed in ->kern_mnt by
* kern_mount() which must be called _after_
* register_filesystem().
*/
#define FS_NOMOUNT 16 /* Never mount from userland */
#define FS_LITTER 32 /* Keeps the tree in dcache */
#define FS_ODD_RENAME 32768 /* Temporary stuff; will go away as soon
* as nfs_rename() will be cleaned up
*/
/*
* These are the fs-independent mount-flags: up to 32 flags are supported
*/
#define MS_RDONLY 1 /* Mount read-only */
#define MS_NOSUID 2 /* Ignore suid and sgid bits */
#define MS_NODEV 4 /* Disallow access to device special files */
#define MS_NOEXEC 8 /* Disallow program execution */
#define MS_SYNCHRONOUS 16 /* Writes are synced at once */
#define MS_REMOUNT 32 /* Alter flags of a mounted FS */
#define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */
#define MS_NOATIME 1024 /* Do not update access times. */
#define MS_NODIRATIME 2048 /* Do not update directory access times */
#define MS_BIND 4096
/*
* Flags that can be altered by MS_REMOUNT
*/
#define MS_RMT_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|\
MS_SYNCHRONOUS|MS_MANDLOCK|MS_NOATIME|MS_NODIRATIME)
/*
* Old magic mount flag and mask
*/
#define MS_MGC_VAL 0xC0ED0000
#define MS_MGC_MSK 0xffff0000
/* Inode flags - they have nothing to superblock flags now */
#define S_SYNC 1 /* Writes are synced at once */
#define S_NOATIME 2 /* Do not update access times */
#define S_QUOTA 4 /* Quota initialized for file */
#define S_APPEND 8 /* Append-only file */
#define S_IMMUTABLE 16 /* Immutable file */
#define S_DEAD 32 /* removed, but still open directory */
/*
* Note that nosuid etc flags are inode-specific: setting some file-system
* flags just means all the inodes inherit those flags by default. It might be
* possible to override it selectively if you really wanted to with some
* ioctl() that is not currently implemented.
*
* Exception: MS_RDONLY is always applied to the entire file system.
*
* Unfortunately, it is possible to change a filesystems flags with it mounted
* with files in use. This means that all of the inodes will not have their
* i_flags updated. Hence, i_flags no longer inherit the superblock mount
* flags, so these have to be checked separately. -- rmk@arm.uk.linux.org
*/
#define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
#define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
#define IS_NOSUID(inode) __IS_FLG(inode, MS_NOSUID)
#define IS_NODEV(inode) __IS_FLG(inode, MS_NODEV)
#define IS_NOEXEC(inode) __IS_FLG(inode, MS_NOEXEC)
#define IS_SYNC(inode) (__IS_FLG(inode, MS_SYNCHRONOUS) || ((inode)->i_flags & S_SYNC))
#define IS_MANDLOCK(inode) __IS_FLG(inode, MS_MANDLOCK)
#define IS_QUOTAINIT(inode) ((inode)->i_flags & S_QUOTA)
#define IS_APPEND(inode) ((inode)->i_flags & S_APPEND)
#define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
#define IS_NOATIME(inode) (__IS_FLG(inode, MS_NOATIME) || ((inode)->i_flags & S_NOATIME))
#define IS_NODIRATIME(inode) __IS_FLG(inode, MS_NODIRATIME)
#define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
/* the read-only stuff doesn't really belong here, but any other place is
probably as bad and I don't want to create yet another include file. */
#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
#define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
#define BLKRRPART _IO(0x12,95) /* re-read partition table */
#define BLKGETSIZE _IO(0x12,96) /* return device size */
#define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
#define BLKRASET _IO(0x12,98) /* Set read ahead for block device */
#define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
#define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
#define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
#define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
#define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
#define BLKSSZGET _IO(0x12,104)/* get block device sector size */
#if 0
#define BLKPG _IO(0x12,105)/* See blkpg.h */
#define BLKELVGET _IOR(0x12,106,sizeof(blkelv_ioctl_arg_t))/* elevator get */
#define BLKELVSET _IOW(0x12,107,sizeof(blkelv_ioctl_arg_t))/* elevator set */
/* This was here just to show that the number is taken -
probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
#endif
#define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
#define FIBMAP _IO(0x00,1) /* bmap access */
#define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
#ifdef __KERNEL__
#include <asm/semaphore.h>
#include <asm/byteorder.h>
extern void update_atime (struct inode *);
#define UPDATE_ATIME(inode) update_atime (inode)
extern void buffer_init(unsigned long);
extern void inode_init(unsigned long);
/* bh state bits */
#define BH_Uptodate 0 /* 1 if the buffer contains valid data */
#define BH_Dirty 1 /* 1 if the buffer is dirty */
#define BH_Lock 2 /* 1 if the buffer is locked */
#define BH_Req 3 /* 0 if the buffer has been invalidated */
#define BH_Mapped 4 /* 1 if the buffer has a disk mapping */
#define BH_New 5 /* 1 if the buffer is new and not yet written out */
#define BH_Protected 6 /* 1 if the buffer is protected */
/*
* Try to keep the most commonly used fields in single cache lines (16
* bytes) to improve performance. This ordering should be
* particularly beneficial on 32-bit processors.
*
* We use the first 16 bytes for the data which is used in searches
* over the block hash lists (ie. getblk() and friends).
*
* The second 16 bytes we use for lru buffer scans, as used by
* sync_buffers() and refill_freelist(). -- sct
*/
struct buffer_head {
/* First cache line: */
struct buffer_head *b_next; /* Hash queue list */
unsigned long b_blocknr; /* block number */
unsigned short b_size; /* block size */
unsigned short b_list; /* List that this buffer appears */
kdev_t b_dev; /* device (B_FREE = free) */
atomic_t b_count; /* users using this block */
kdev_t b_rdev; /* Real device */
unsigned long b_state; /* buffer state bitmap (see above) */
unsigned long b_flushtime; /* Time when (dirty) buffer should be written */
struct buffer_head *b_next_free;/* lru/free list linkage */
struct buffer_head *b_prev_free;/* doubly linked list of buffers */
struct buffer_head *b_this_page;/* circular list of buffers in one page */
struct buffer_head *b_reqnext; /* request queue */
struct buffer_head **b_pprev; /* doubly linked list of hash-queue */
char * b_data; /* pointer to data block */
struct page *b_page; /* the page this bh is mapped to */
void (*b_end_io)(struct buffer_head *bh, int uptodate); /* I/O completion */
void *b_private; /* reserved for b_end_io */
unsigned long b_rsector; /* Real buffer location on disk */
wait_queue_head_t b_wait;
struct inode * b_inode;
struct list_head b_inode_buffers; /* doubly linked list of inode dirty buffers */
};
typedef void (bh_end_io_t)(struct buffer_head *bh, int uptodate);
void init_buffer(struct buffer_head *, bh_end_io_t *, void *);
#define __buffer_state(bh, state) (((bh)->b_state & (1UL << BH_##state)) != 0)
#define buffer_uptodate(bh) __buffer_state(bh,Uptodate)
#define buffer_dirty(bh) __buffer_state(bh,Dirty)
#define buffer_locked(bh) __buffer_state(bh,Lock)
#define buffer_req(bh) __buffer_state(bh,Req)
#define buffer_mapped(bh) __buffer_state(bh,Mapped)
#define buffer_new(bh) __buffer_state(bh,New)
#define buffer_protected(bh) __buffer_state(bh,Protected)
#define bh_offset(bh) ((unsigned long)(bh)->b_data & ~PAGE_MASK)
extern void set_bh_page(struct buffer_head *bh, struct page *page, unsigned long offset);
#define touch_buffer(bh) SetPageReferenced(bh->b_page)
#include <linux/pipe_fs_i.h>
#include <linux/minix_fs_i.h>
#include <linux/ext2_fs_i.h>
#include <linux/hpfs_fs_i.h>
#include <linux/ntfs_fs_i.h>
#include <linux/msdos_fs_i.h>
#include <linux/umsdos_fs_i.h>
#include <linux/iso_fs_i.h>
#include <linux/nfs_fs_i.h>
#include <linux/sysv_fs_i.h>
#include <linux/affs_fs_i.h>
#include <linux/ufs_fs_i.h>
#include <linux/efs_fs_i.h>
#include <linux/coda_fs_i.h>
#include <linux/romfs_fs_i.h>
#include <linux/shmem_fs.h>
#include <linux/smb_fs_i.h>
#include <linux/hfs_fs_i.h>
#include <linux/adfs_fs_i.h>
#include <linux/qnx4_fs_i.h>
#include <linux/reiserfs_fs_i.h>
#include <linux/bfs_fs_i.h>
#include <linux/udf_fs_i.h>
#include <linux/ncp_fs_i.h>
#include <linux/proc_fs_i.h>
#include <linux/usbdev_fs_i.h>
/*
* Attribute flags. These should be or-ed together to figure out what
* has been changed!
*/
#define ATTR_MODE 1
#define ATTR_UID 2
#define ATTR_GID 4
#define ATTR_SIZE 8
#define ATTR_ATIME 16
#define ATTR_MTIME 32
#define ATTR_CTIME 64
#define ATTR_ATIME_SET 128
#define ATTR_MTIME_SET 256
#define ATTR_FORCE 512 /* Not a change, but a change it */
#define ATTR_ATTR_FLAG 1024
/*
* This is the Inode Attributes structure, used for notify_change(). It
* uses the above definitions as flags, to know which values have changed.
* Also, in this manner, a Filesystem can look at only the values it cares
* about. Basically, these are the attributes that the VFS layer can
* request to change from the FS layer.
*
* Derek Atkins <warlord@MIT.EDU> 94-10-20
*/
struct iattr {
unsigned int ia_valid;
umode_t ia_mode;
uid_t ia_uid;
gid_t ia_gid;
loff_t ia_size;
time_t ia_atime;
time_t ia_mtime;
time_t ia_ctime;
unsigned int ia_attr_flags;
};
/*
* This is the inode attributes flag definitions
*/
#define ATTR_FLAG_SYNCRONOUS 1 /* Syncronous write */
#define ATTR_FLAG_NOATIME 2 /* Don't update atime */
#define ATTR_FLAG_APPEND 4 /* Append-only file */
#define ATTR_FLAG_IMMUTABLE 8 /* Immutable file */
#define ATTR_FLAG_NODIRATIME 16 /* Don't update atime for directory */
/*
* Includes for diskquotas and mount structures.
*/
#include <linux/quota.h>
#include <linux/mount.h>
/*
* oh the beauties of C type declarations.
*/
struct page;
struct address_space;
struct address_space_operations {
int (*writepage)(struct page *);
int (*readpage)(struct file *, struct page *);
int (*sync_page)(struct page *);
int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
/* Unfortunately this kludge is needed for FIBMAP. Don't use it */
int (*bmap)(struct address_space *, long);
};
struct address_space {
struct list_head clean_pages; /* list of clean pages */
struct list_head dirty_pages; /* list of dirty pages */
struct list_head locked_pages; /* list of locked pages */
unsigned long nrpages; /* number of total pages */
struct address_space_operations *a_ops; /* methods */
struct inode *host; /* owner: inode, block_device */
struct vm_area_struct *i_mmap; /* list of private mappings */
struct vm_area_struct *i_mmap_shared; /* list of shared mappings */
spinlock_t i_shared_lock; /* and spinlock protecting it */
int gfp_mask; /* how to allocate the pages */
};
struct char_device {
struct list_head hash;
atomic_t count;
dev_t dev;
atomic_t openers;
struct semaphore sem;
};
struct block_device {
struct list_head bd_hash;
atomic_t bd_count;
/* struct address_space bd_data; */
dev_t bd_dev; /* not a kdev_t - it's a search key */
atomic_t bd_openers;
const struct block_device_operations *bd_op;
struct semaphore bd_sem; /* open/close mutex */
};
struct inode {
struct list_head i_hash;
struct list_head i_list;
struct list_head i_dentry;
struct list_head i_dirty_buffers;
unsigned long i_ino;
atomic_t i_count;
kdev_t i_dev;
umode_t i_mode;
nlink_t i_nlink;
uid_t i_uid;
gid_t i_gid;
kdev_t i_rdev;
loff_t i_size;
time_t i_atime;
time_t i_mtime;
time_t i_ctime;
unsigned long i_blksize;
unsigned long i_blocks;
unsigned long i_version;
struct semaphore i_sem;
struct semaphore i_zombie;
struct inode_operations *i_op;
struct file_operations *i_fop; /* former ->i_op->default_file_ops */
struct super_block *i_sb;
wait_queue_head_t i_wait;
struct file_lock *i_flock;
struct address_space *i_mapping;
struct address_space i_data;
struct dquot *i_dquot[MAXQUOTAS];
/* These three should probably be a union */
struct pipe_inode_info *i_pipe;
struct block_device *i_bdev;
struct char_device *i_cdev;
unsigned long i_dnotify_mask; /* Directory notify events */
struct dnotify_struct *i_dnotify; /* for directory notifications */
unsigned long i_state;
unsigned int i_flags;
unsigned char i_sock;
atomic_t i_writecount;
unsigned int i_attr_flags;
__u32 i_generation;
union {
struct minix_inode_info minix_i;
struct ext2_inode_info ext2_i;
struct hpfs_inode_info hpfs_i;
struct ntfs_inode_info ntfs_i;
struct msdos_inode_info msdos_i;
struct umsdos_inode_info umsdos_i;
struct iso_inode_info isofs_i;
struct nfs_inode_info nfs_i;
struct sysv_inode_info sysv_i;
struct affs_inode_info affs_i;
struct ufs_inode_info ufs_i;
struct efs_inode_info efs_i;
struct romfs_inode_info romfs_i;
struct shmem_inode_info shmem_i;
struct coda_inode_info coda_i;
struct smb_inode_info smbfs_i;
struct hfs_inode_info hfs_i;
struct adfs_inode_info adfs_i;
struct qnx4_inode_info qnx4_i;
struct reiserfs_inode_info reiserfs_i;
struct bfs_inode_info bfs_i;
struct udf_inode_info udf_i;
struct ncp_inode_info ncpfs_i;
struct proc_inode_info proc_i;
struct socket socket_i;
struct usbdev_inode_info usbdev_i;
void *generic_ip;
} u;
};
struct fown_struct {
int pid; /* pid or -pgrp where SIGIO should be sent */
uid_t uid, euid; /* uid/euid of process setting the owner */
int signum; /* posix.1b rt signal to be delivered on IO */
};
struct file {
struct list_head f_list;
struct dentry *f_dentry;
struct vfsmount *f_vfsmnt;
struct file_operations *f_op;
atomic_t f_count;
unsigned int f_flags;
mode_t f_mode;
loff_t f_pos;
unsigned long f_reada, f_ramax, f_raend, f_ralen, f_rawin;
struct fown_struct f_owner;
unsigned int f_uid, f_gid;
int f_error;
unsigned long f_version;
/* needed for tty driver, and maybe others */
void *private_data;
};
extern spinlock_t files_lock;
#define file_list_lock() spin_lock(&files_lock);
#define file_list_unlock() spin_unlock(&files_lock);
#define get_file(x) atomic_inc(&(x)->f_count)
#define file_count(x) atomic_read(&(x)->f_count)
extern int init_private_file(struct file *, struct dentry *, int);
#define MAX_NON_LFS ((1UL<<31) - 1)
#define FL_POSIX 1
#define FL_FLOCK 2
#define FL_BROKEN 4 /* broken flock() emulation */
#define FL_ACCESS 8 /* for processes suspended by mandatory locking */
#define FL_LOCKD 16 /* lock held by rpc.lockd */
#define FL_LEASE 32 /* lease held on this file */
/*
* The POSIX file lock owner is determined by
* the "struct files_struct" in the thread group
* (or NULL for no owner - BSD locks).
*
* Lockd stuffs a "host" pointer into this.
*/
typedef struct files_struct *fl_owner_t;
struct file_lock {
struct file_lock *fl_next; /* singly linked list for this inode */
struct list_head fl_link; /* doubly linked list of all locks */
struct list_head fl_block; /* circular list of blocked processes */
fl_owner_t fl_owner;
unsigned int fl_pid;
wait_queue_head_t fl_wait;
struct file *fl_file;
unsigned char fl_flags;
unsigned char fl_type;
loff_t fl_start;
loff_t fl_end;
void (*fl_notify)(struct file_lock *); /* unblock callback */
void (*fl_insert)(struct file_lock *); /* lock insertion callback */
void (*fl_remove)(struct file_lock *); /* lock removal callback */
struct fasync_struct * fl_fasync; /* for lease break notifications */
union {
struct nfs_lock_info nfs_fl;
} fl_u;
};
/* The following constant reflects the upper bound of the file/locking space */
#ifndef OFFSET_MAX
#define INT_LIMIT(x) (~((x)1 << (sizeof(x)*8 - 1)))
#define OFFSET_MAX INT_LIMIT(loff_t)
#define OFFT_OFFSET_MAX INT_LIMIT(off_t)
#endif
extern struct list_head file_lock_list;
#include <linux/fcntl.h>
extern int fcntl_getlk(unsigned int, struct flock *);
extern int fcntl_setlk(unsigned int, unsigned int, struct flock *);
extern int fcntl_getlk64(unsigned int, struct flock64 *);
extern int fcntl_setlk64(unsigned int, unsigned int, struct flock64 *);
/* fs/locks.c */
extern void locks_init_lock(struct file_lock *);
extern void locks_copy_lock(struct file_lock *, struct file_lock *);
extern void locks_remove_posix(struct file *, fl_owner_t);
extern void locks_remove_flock(struct file *);
extern struct file_lock *posix_test_lock(struct file *, struct file_lock *);
extern int posix_lock_file(struct file *, struct file_lock *, unsigned int);
extern void posix_block_lock(struct file_lock *, struct file_lock *);
extern void posix_unblock_lock(struct file_lock *);
extern int __get_lease(struct inode *inode, unsigned int flags);
extern time_t lease_get_mtime(struct inode *);
extern int lock_may_read(struct inode *, loff_t start, unsigned long count);
extern int lock_may_write(struct inode *, loff_t start, unsigned long count);
struct fasync_struct {
int magic;
int fa_fd;
struct fasync_struct *fa_next; /* singly linked list */
struct file *fa_file;
};
#define FASYNC_MAGIC 0x4601
/* SMP safe fasync helpers: */
extern int fasync_helper(int, struct file *, int, struct fasync_struct **);
/* can be called from interrupts */
extern void kill_fasync(struct fasync_struct **, int, int);
/* only for net: no internal synchronization */
extern void __kill_fasync(struct fasync_struct *, int, int);
struct nameidata {
struct dentry *dentry;
struct vfsmount *mnt;
struct qstr last;
unsigned int flags;
int last_type;
};
#define DQUOT_USR_ENABLED 0x01 /* User diskquotas enabled */
#define DQUOT_GRP_ENABLED 0x02 /* Group diskquotas enabled */
struct quota_mount_options
{
unsigned int flags; /* Flags for diskquotas on this device */
struct semaphore dqio_sem; /* lock device while I/O in progress */
struct semaphore dqoff_sem; /* serialize quota_off() and quota_on() on device */
struct file *files[MAXQUOTAS]; /* fp's to quotafiles */
time_t inode_expire[MAXQUOTAS]; /* expiretime for inode-quota */
time_t block_expire[MAXQUOTAS]; /* expiretime for block-quota */
char rsquash[MAXQUOTAS]; /* for quotas threat root as any other user */
};
/*
* Umount options
*/
#define MNT_FORCE 0x00000001 /* Attempt to forcibily umount */
#include <linux/minix_fs_sb.h>
#include <linux/ext2_fs_sb.h>
#include <linux/hpfs_fs_sb.h>
#include <linux/ntfs_fs_sb.h>
#include <linux/msdos_fs_sb.h>
#include <linux/iso_fs_sb.h>
#include <linux/nfs_fs_sb.h>
#include <linux/sysv_fs_sb.h>
#include <linux/affs_fs_sb.h>
#include <linux/ufs_fs_sb.h>
#include <linux/efs_fs_sb.h>
#include <linux/romfs_fs_sb.h>
#include <linux/smb_fs_sb.h>
#include <linux/hfs_fs_sb.h>
#include <linux/adfs_fs_sb.h>
#include <linux/qnx4_fs_sb.h>
#include <linux/reiserfs_fs_sb.h>
#include <linux/bfs_fs_sb.h>
#include <linux/udf_fs_sb.h>
#include <linux/ncp_fs_sb.h>
#include <linux/usbdev_fs_sb.h>
extern struct list_head super_blocks;
#define sb_entry(list) list_entry((list), struct super_block, s_list)
struct super_block {
struct list_head s_list; /* Keep this first */
kdev_t s_dev;
unsigned long s_blocksize;
unsigned char s_blocksize_bits;
unsigned char s_dirt;
unsigned long long s_maxbytes; /* Max file size */
struct file_system_type *s_type;
struct super_operations *s_op;
struct dquot_operations *dq_op;
unsigned long s_flags;
unsigned long s_magic;
struct dentry *s_root;
struct rw_semaphore s_umount;
struct semaphore s_lock;
struct list_head s_dirty; /* dirty inodes */
struct list_head s_locked_inodes;/* inodes being synced */
struct list_head s_files;
struct block_device *s_bdev;
struct list_head s_mounts; /* vfsmount(s) of this one */
struct quota_mount_options s_dquot; /* Diskquota specific options */
union {
struct minix_sb_info minix_sb;
struct ext2_sb_info ext2_sb;
struct hpfs_sb_info hpfs_sb;
struct ntfs_sb_info ntfs_sb;
struct msdos_sb_info msdos_sb;
struct isofs_sb_info isofs_sb;
struct nfs_sb_info nfs_sb;
struct sysv_sb_info sysv_sb;
struct affs_sb_info affs_sb;
struct ufs_sb_info ufs_sb;
struct efs_sb_info efs_sb;
struct shmem_sb_info shmem_sb;
struct romfs_sb_info romfs_sb;
struct smb_sb_info smbfs_sb;
struct hfs_sb_info hfs_sb;
struct adfs_sb_info adfs_sb;
struct qnx4_sb_info qnx4_sb;
struct reiserfs_sb_info reiserfs_sb;
struct bfs_sb_info bfs_sb;
struct udf_sb_info udf_sb;
struct ncp_sb_info ncpfs_sb;
struct usbdev_sb_info usbdevfs_sb;
void *generic_sbp;
} u;
/*
* The next field is for VFS *only*. No filesystems have any business
* even looking at it. You had been warned.
*/
struct semaphore s_vfs_rename_sem; /* Kludge */
/* The next field is used by knfsd when converting a (inode number based)
* file handle into a dentry. As it builds a path in the dcache tree from
* the bottom up, there may for a time be a subpath of dentrys which is not
* connected to the main tree. This semaphore ensure that there is only ever
* one such free path per filesystem. Note that unconnected files (or other
* non-directories) are allowed, but not unconnected diretories.
*/
struct semaphore s_nfsd_free_path_sem;
};
/*
* VFS helper functions..
*/
extern int vfs_create(struct inode *, struct dentry *, int);
extern int vfs_mkdir(struct inode *, struct dentry *, int);
extern int vfs_mknod(struct inode *, struct dentry *, int, dev_t);
extern int vfs_symlink(struct inode *, struct dentry *, const char *);
extern int vfs_link(struct dentry *, struct inode *, struct dentry *);
extern int vfs_rmdir(struct inode *, struct dentry *);
extern int vfs_unlink(struct inode *, struct dentry *);
extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *);
/*
* File types
*/
#define DT_UNKNOWN 0
#define DT_FIFO 1
#define DT_CHR 2
#define DT_DIR 4
#define DT_BLK 6
#define DT_REG 8
#define DT_LNK 10
#define DT_SOCK 12
#define DT_WHT 14
/*
* This is the "filldir" function type, used by readdir() to let
* the kernel specify what kind of dirent layout it wants to have.
* This allows the kernel to read directories into kernel space or
* to have different dirent layouts depending on the binary type.
*/
typedef int (*filldir_t)(void *, const char *, int, off_t, ino_t, unsigned);
struct block_device_operations {
int (*open) (struct inode *, struct file *);
int (*release) (struct inode *, struct file *);
int (*ioctl) (struct inode *, struct file *, unsigned, unsigned long);
int (*check_media_change) (kdev_t);
int (*revalidate) (kdev_t);
};
/*
* NOTE:
* read, write, poll, fsync, readv, writev can be called
* without the big kernel lock held in all filesystems.
*/
struct file_operations {
struct module *owner;
loff_t (*llseek) (struct file *, loff_t, int);
ssize_t (*read) (struct file *, char *, size_t, loff_t *);
ssize_t (*write) (struct file *, const char *, size_t, loff_t *);
int (*readdir) (struct file *, void *, filldir_t);
unsigned int (*poll) (struct file *, struct poll_table_struct *);
int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long);
int (*mmap) (struct file *, struct vm_area_struct *);
int (*open) (struct inode *, struct file *);
int (*flush) (struct file *);
int (*release) (struct inode *, struct file *);
int (*fsync) (struct file *, struct dentry *, int datasync);
int (*fasync) (int, struct file *, int);
int (*lock) (struct file *, int, struct file_lock *);
ssize_t (*readv) (struct file *, const struct iovec *, unsigned long, loff_t *);
ssize_t (*writev) (struct file *, const struct iovec *, unsigned long, loff_t *);
ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
};
struct inode_operations {
int (*create) (struct inode *,struct dentry *,int);
struct dentry * (*lookup) (struct inode *,struct dentry *);
int (*link) (struct dentry *,struct inode *,struct dentry *);
int (*unlink) (struct inode *,struct dentry *);
int (*symlink) (struct inode *,struct dentry *,const char *);
int (*mkdir) (struct inode *,struct dentry *,int);
int (*rmdir) (struct inode *,struct dentry *);
int (*mknod) (struct inode *,struct dentry *,int,int);
int (*rename) (struct inode *, struct dentry *,
struct inode *, struct dentry *);
int (*readlink) (struct dentry *, char *,int);
int (*follow_link) (struct dentry *, struct nameidata *);
void (*truncate) (struct inode *);
int (*permission) (struct inode *, int);
int (*revalidate) (struct dentry *);
int (*setattr) (struct dentry *, struct iattr *);
int (*getattr) (struct dentry *, struct iattr *);
};
/*
* NOTE: write_inode, delete_inode, clear_inode, put_inode can be called
* without the big kernel lock held in all filesystems.
*/
struct super_operations {
void (*read_inode) (struct inode *);
/* reiserfs kludge. reiserfs needs 64 bits of information to
** find an inode. We are using the read_inode2 call to get
** that information. We don't like this, and are waiting on some
** VFS changes for the real solution.
** iget4 calls read_inode2, iff it is defined
*/
void (*read_inode2) (struct inode *, void *) ;
void (*dirty_inode) (struct inode *);
void (*write_inode) (struct inode *, int);
void (*put_inode) (struct inode *);
void (*delete_inode) (struct inode *);
void (*put_super) (struct super_block *);
void (*write_super) (struct super_block *);
void (*write_super_lockfs) (struct super_block *);
void (*unlockfs) (struct super_block *);
int (*statfs) (struct super_block *, struct statfs *);
int (*remount_fs) (struct super_block *, int *, char *);
void (*clear_inode) (struct inode *);
void (*umount_begin) (struct super_block *);
};
/* Inode state bits.. */
#define I_DIRTY_SYNC 1 /* Not dirty enough for O_DATASYNC */
#define I_DIRTY_DATASYNC 2 /* Data-related inode changes pending */
#define I_DIRTY_PAGES 4 /* Data-related inode changes pending */
#define I_LOCK 8
#define I_FREEING 16
#define I_CLEAR 32
#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
extern void __mark_inode_dirty(struct inode *, int);
static inline void mark_inode_dirty(struct inode *inode)
{
__mark_inode_dirty(inode, I_DIRTY);
}
static inline void mark_inode_dirty_sync(struct inode *inode)
{
__mark_inode_dirty(inode, I_DIRTY_SYNC);
}
static inline void mark_inode_dirty_pages(struct inode *inode)
{
__mark_inode_dirty(inode, I_DIRTY_PAGES);
}
struct dquot_operations {
void (*initialize) (struct inode *, short);
void (*drop) (struct inode *);
int (*alloc_block) (const struct inode *, unsigned long, char);
int (*alloc_inode) (const struct inode *, unsigned long);
void (*free_block) (const struct inode *, unsigned long);
void (*free_inode) (const struct inode *, unsigned long);
int (*transfer) (struct dentry *, struct iattr *);
};
struct file_system_type {
const char *name;
int fs_flags;
struct super_block *(*read_super) (struct super_block *, void *, int);
struct module *owner;
struct vfsmount *kern_mnt; /* For kernel mount, if it's FS_SINGLE fs */
struct file_system_type * next;
};
#define DECLARE_FSTYPE(var,type,read,flags) \
struct file_system_type var = { \
name: type, \
read_super: read, \
fs_flags: flags, \
owner: THIS_MODULE, \
}
#define DECLARE_FSTYPE_DEV(var,type,read) \
DECLARE_FSTYPE(var,type,read,FS_REQUIRES_DEV)
/* Alas, no aliases. Too much hassle with bringing module.h everywhere */
#define fops_get(fops) \
(((fops) && (fops)->owner) \
? ( try_inc_mod_count((fops)->owner) ? (fops) : NULL ) \
: (fops))
#define fops_put(fops) \
do { \
if ((fops) && (fops)->owner) \
__MOD_DEC_USE_COUNT((fops)->owner); \
} while(0)
extern int register_filesystem(struct file_system_type *);
extern int unregister_filesystem(struct file_system_type *);
extern struct vfsmount *kern_mount(struct file_system_type *);
extern int may_umount(struct vfsmount *);
extern long do_mount(char *, char *, char *, unsigned long, void *);
#define kern_umount mntput
extern int vfs_statfs(struct super_block *, struct statfs *);
/* Return value for VFS lock functions - tells locks.c to lock conventionally
* REALLY kosha for root NFS and nfs_lock
*/
#define LOCK_USE_CLNT 1
#define FLOCK_VERIFY_READ 1
#define FLOCK_VERIFY_WRITE 2
extern int locks_mandatory_locked(struct inode *);
extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
/*
* Candidates for mandatory locking have the setgid bit set
* but no group execute bit - an otherwise meaningless combination.
*/
#define MANDATORY_LOCK(inode) \
(IS_MANDLOCK(inode) && ((inode)->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
static inline int locks_verify_locked(struct inode *inode)
{
if (MANDATORY_LOCK(inode))
return locks_mandatory_locked(inode);
return 0;
}
static inline int locks_verify_area(int read_write, struct inode *inode,
struct file *filp, loff_t offset,
size_t count)
{
if (inode->i_flock && MANDATORY_LOCK(inode))
return locks_mandatory_area(read_write, inode, filp, offset, count);
return 0;
}
static inline int locks_verify_truncate(struct inode *inode,
struct file *filp,
loff_t size)
{
if (inode->i_flock && MANDATORY_LOCK(inode))
return locks_mandatory_area(
FLOCK_VERIFY_WRITE, inode, filp,
size < inode->i_size ? size : inode->i_size,
(size < inode->i_size ? inode->i_size - size
: size - inode->i_size)
);
return 0;
}
extern inline int get_lease(struct inode *inode, unsigned int mode)
{
if (inode->i_flock && (inode->i_flock->fl_flags & FL_LEASE))
return __get_lease(inode, mode);
return 0;
}
/* fs/open.c */
asmlinkage long sys_open(const char *, int, int);
asmlinkage long sys_close(unsigned int); /* yes, it's really unsigned */
extern int do_truncate(struct dentry *, loff_t start);
extern struct file *filp_open(const char *, int, int);
extern struct file * dentry_open(struct dentry *, struct vfsmount *, int);
extern int filp_close(struct file *, fl_owner_t id);
extern char * getname(const char *);
/* fs/dcache.c */
extern void vfs_caches_init(unsigned long);
#define __getname() kmem_cache_alloc(names_cachep, SLAB_KERNEL)
#define putname(name) kmem_cache_free(names_cachep, (void *)(name))
enum {BDEV_FILE, BDEV_SWAP, BDEV_FS, BDEV_RAW};
extern int register_blkdev(unsigned int, const char *, struct block_device_operations *);
extern int unregister_blkdev(unsigned int, const char *);
extern struct block_device *bdget(dev_t);
extern void bdput(struct block_device *);
extern struct char_device *cdget(dev_t);
extern void cdput(struct char_device *);
extern int blkdev_open(struct inode *, struct file *);
extern struct file_operations def_blk_fops;
extern struct file_operations def_fifo_fops;
extern int ioctl_by_bdev(struct block_device *, unsigned, unsigned long);
extern int blkdev_get(struct block_device *, mode_t, unsigned, int);
extern int blkdev_put(struct block_device *, int);
/* fs/devices.c */
extern const struct block_device_operations *get_blkfops(unsigned int);
extern int register_chrdev(unsigned int, const char *, struct file_operations *);
extern int unregister_chrdev(unsigned int, const char *);
extern int chrdev_open(struct inode *, struct file *);
extern const char * bdevname(kdev_t);
extern const char * cdevname(kdev_t);
extern const char * kdevname(kdev_t);
extern void init_special_inode(struct inode *, umode_t, int);
/* Invalid inode operations -- fs/bad_inode.c */
extern void make_bad_inode(struct inode *);
extern int is_bad_inode(struct inode *);
extern struct file_operations read_fifo_fops;
extern struct file_operations write_fifo_fops;
extern struct file_operations rdwr_fifo_fops;
extern struct file_operations read_pipe_fops;
extern struct file_operations write_pipe_fops;
extern struct file_operations rdwr_pipe_fops;
extern int fs_may_remount_ro(struct super_block *);
extern int try_to_free_buffers(struct page *, int);
extern void refile_buffer(struct buffer_head * buf);
/* reiserfs_writepage needs this */
extern void set_buffer_async_io(struct buffer_head *bh) ;
#define BUF_CLEAN 0
#define BUF_LOCKED 1 /* Buffers scheduled for write */
#define BUF_DIRTY 2 /* Dirty buffers, not yet scheduled for write */
#define BUF_PROTECTED 3 /* Ramdisk persistent storage */
#define NR_LIST 4
/*
* This is called by bh->b_end_io() handlers when I/O has completed.
*/
static inline void mark_buffer_uptodate(struct buffer_head * bh, int on)
{
if (on)
set_bit(BH_Uptodate, &bh->b_state);
else
clear_bit(BH_Uptodate, &bh->b_state);
}
#define atomic_set_buffer_clean(bh) test_and_clear_bit(BH_Dirty, &(bh)->b_state)
static inline void __mark_buffer_clean(struct buffer_head *bh)
{
refile_buffer(bh);
}
static inline void mark_buffer_clean(struct buffer_head * bh)
{
if (atomic_set_buffer_clean(bh))
__mark_buffer_clean(bh);
}
#define atomic_set_buffer_protected(bh) test_and_set_bit(BH_Protected, &(bh)->b_state)
static inline void __mark_buffer_protected(struct buffer_head *bh)
{
refile_buffer(bh);
}
static inline void mark_buffer_protected(struct buffer_head * bh)
{
if (!atomic_set_buffer_protected(bh))
__mark_buffer_protected(bh);
}
extern void FASTCALL(__mark_buffer_dirty(struct buffer_head *bh));
extern void FASTCALL(mark_buffer_dirty(struct buffer_head *bh));
#define atomic_set_buffer_dirty(bh) test_and_set_bit(BH_Dirty, &(bh)->b_state)
/*
* If an error happens during the make_request, this function
* has to be recalled. It marks the buffer as clean and not
* uptodate, and it notifys the upper layer about the end
* of the I/O.
*/
static inline void buffer_IO_error(struct buffer_head * bh)
{
mark_buffer_clean(bh);
/*
* b_end_io has to clear the BH_Uptodate bitflag in the error case!
*/
bh->b_end_io(bh, 0);
}
extern void buffer_insert_inode_queue(struct buffer_head *, struct inode *);
static inline void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode)
{
mark_buffer_dirty(bh);
buffer_insert_inode_queue(bh, inode);
}
extern void balance_dirty(kdev_t);
extern int check_disk_change(kdev_t);
extern int invalidate_inodes(struct super_block *);
extern int invalidate_device(kdev_t, int);
extern void invalidate_inode_pages(struct inode *);
extern void invalidate_inode_buffers(struct inode *);
#define invalidate_buffers(dev) __invalidate_buffers((dev), 0)
#define destroy_buffers(dev) __invalidate_buffers((dev), 1)
extern void __invalidate_buffers(kdev_t dev, int);
extern void sync_inodes(kdev_t);
extern void sync_unlocked_inodes(void);
extern void write_inode_now(struct inode *, int);
extern void sync_dev(kdev_t);
extern int fsync_dev(kdev_t);
extern int fsync_super(struct super_block *);
extern void sync_inodes_sb(struct super_block *);
extern int fsync_inode_buffers(struct inode *);
extern int osync_inode_buffers(struct inode *);
extern int inode_has_buffers(struct inode *);
extern void filemap_fdatasync(struct address_space *);
extern void filemap_fdatawait(struct address_space *);
extern void sync_supers(kdev_t);
extern int bmap(struct inode *, int);
extern int notify_change(struct dentry *, struct iattr *);
extern int permission(struct inode *, int);
extern int vfs_permission(struct inode *, int);
extern int get_write_access(struct inode *);
extern int deny_write_access(struct file *);
static inline void put_write_access(struct inode * inode)
{
atomic_dec(&inode->i_writecount);
}
static inline void allow_write_access(struct file *file)
{
if (file)
atomic_inc(&file->f_dentry->d_inode->i_writecount);
}
extern int do_pipe(int *);
extern int open_namei(const char *, int, int, struct nameidata *);
extern int kernel_read(struct file *, unsigned long, char *, unsigned long);
extern struct file * open_exec(const char *);
/* fs/dcache.c -- generic fs support functions */
extern int is_subdir(struct dentry *, struct dentry *);
extern ino_t find_inode_number(struct dentry *, struct qstr *);
/*
* Kernel pointers have redundant information, so we can use a
* scheme where we can return either an error code or a dentry
* pointer with the same return value.
*
* This should be a per-architecture thing, to allow different
* error and pointer decisions.
*/
static inline void *ERR_PTR(long error)
{
return (void *) error;
}
static inline long PTR_ERR(const void *ptr)
{
return (long) ptr;
}
static inline long IS_ERR(const void *ptr)
{
return (unsigned long)ptr > (unsigned long)-1000L;
}
/*
* The bitmask for a lookup event:
* - follow links at the end
* - require a directory
* - ending slashes ok even for nonexistent files
* - internal "there are more path compnents" flag
*/
#define LOOKUP_FOLLOW (1)
#define LOOKUP_DIRECTORY (2)
#define LOOKUP_CONTINUE (4)
#define LOOKUP_POSITIVE (8)
#define LOOKUP_PARENT (16)
#define LOOKUP_NOALT (32)
/*
* Type of the last component on LOOKUP_PARENT
*/
enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
/*
* "descriptor" for what we're up to with a read for sendfile().
* This allows us to use the same read code yet
* have multiple different users of the data that
* we read from a file.
*
* The simplest case just copies the data to user
* mode.
*/
typedef struct {
size_t written;
size_t count;
char * buf;
int error;
} read_descriptor_t;
typedef int (*read_actor_t)(read_descriptor_t *, struct page *, unsigned long, unsigned long);
/* needed for stackable file system support */
extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
extern int __user_walk(const char *, unsigned, struct nameidata *);
extern int path_init(const char *, unsigned, struct nameidata *);
extern int path_walk(const char *, struct nameidata *);
extern void path_release(struct nameidata *);
extern int follow_down(struct vfsmount **, struct dentry **);
extern int follow_up(struct vfsmount **, struct dentry **);
extern struct dentry * lookup_one_len(const char *, struct dentry *, int);
extern struct dentry * lookup_hash(struct qstr *, struct dentry *);
#define user_path_walk(name,nd) __user_walk(name, LOOKUP_FOLLOW|LOOKUP_POSITIVE, nd)
#define user_path_walk_link(name,nd) __user_walk(name, LOOKUP_POSITIVE, nd)
extern void iput(struct inode *);
extern void force_delete(struct inode *);
extern struct inode * igrab(struct inode *);
extern ino_t iunique(struct super_block *, ino_t);
typedef int (*find_inode_t)(struct inode *, unsigned long, void *);
extern struct inode * iget4(struct super_block *, unsigned long, find_inode_t, void *);
static inline struct inode *iget(struct super_block *sb, unsigned long ino)
{
return iget4(sb, ino, NULL, NULL);
}
extern void clear_inode(struct inode *);
extern struct inode * get_empty_inode(void);
static inline struct inode * new_inode(struct super_block *sb)
{
struct inode *inode = get_empty_inode();
if (inode) {
inode->i_sb = sb;
inode->i_dev = sb->s_dev;
}
return inode;
}
extern void remove_suid(struct inode *inode);
extern void insert_inode_hash(struct inode *);
extern void remove_inode_hash(struct inode *);
extern struct file * get_empty_filp(void);
extern void file_move(struct file *f, struct list_head *list);
extern void file_moveto(struct file *new, struct file *old);
extern struct buffer_head * get_hash_table(kdev_t, int, int);
extern struct buffer_head * getblk(kdev_t, int, int);
extern void ll_rw_block(int, int, struct buffer_head * bh[]);
extern void submit_bh(int, struct buffer_head *);
extern int is_read_only(kdev_t);
extern void __brelse(struct buffer_head *);
static inline void brelse(struct buffer_head *buf)
{
if (buf)
__brelse(buf);
}
extern void __bforget(struct buffer_head *);
static inline void bforget(struct buffer_head *buf)
{
if (buf)
__bforget(buf);
}
extern void set_blocksize(kdev_t, int);
extern struct buffer_head * bread(kdev_t, int, int);
extern void wakeup_bdflush(int wait);
extern int brw_page(int, struct page *, kdev_t, int [], int);
typedef int (get_block_t)(struct inode*,long,struct buffer_head*,int);
/* Generic buffer handling for block filesystems.. */
extern int block_flushpage(struct page *, unsigned long);
extern int block_symlink(struct inode *, const char *, int);
extern int block_write_full_page(struct page*, get_block_t*);
extern int block_read_full_page(struct page*, get_block_t*);
extern int block_prepare_write(struct page*, unsigned, unsigned, get_block_t*);
extern int cont_prepare_write(struct page*, unsigned, unsigned, get_block_t*,
unsigned long *);
extern int block_sync_page(struct page *);
int generic_block_bmap(struct address_space *, long, get_block_t *);
int generic_commit_write(struct file *, struct page *, unsigned, unsigned);
int block_truncate_page(struct address_space *, loff_t, get_block_t *);
extern int waitfor_one_page(struct page*);
extern int generic_file_mmap(struct file *, struct vm_area_struct *);
extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
extern ssize_t generic_file_read(struct file *, char *, size_t, loff_t *);
extern ssize_t generic_file_write(struct file *, const char *, size_t, loff_t *);
extern void do_generic_file_read(struct file *, loff_t *, read_descriptor_t *, read_actor_t);
extern ssize_t generic_read_dir(struct file *, char *, size_t, loff_t *);
extern struct file_operations generic_ro_fops;
extern int vfs_readlink(struct dentry *, char *, int, const char *);
extern int vfs_follow_link(struct nameidata *, const char *);
extern int page_readlink(struct dentry *, char *, int);
extern int page_follow_link(struct dentry *, struct nameidata *);
extern struct inode_operations page_symlink_inode_operations;
extern int vfs_readdir(struct file *, filldir_t, void *);
extern int dcache_readdir(struct file *, void *, filldir_t);
extern struct file_system_type *get_fs_type(const char *name);
extern struct super_block *get_super(kdev_t);
extern void put_super(kdev_t);
static inline int is_mounted(kdev_t dev)
{
struct super_block *sb = get_super(dev);
if (sb) {
/* drop_super(sb); will go here */
return 1;
}
return 0;
}
unsigned long generate_cluster(kdev_t, int b[], int);
unsigned long generate_cluster_swab32(kdev_t, int b[], int);
extern kdev_t ROOT_DEV;
extern char root_device_name[];
extern void show_buffers(void);
extern void mount_root(void);
#ifdef CONFIG_BLK_DEV_INITRD
extern kdev_t real_root_dev;
extern int change_root(kdev_t, const char *);
#endif
extern ssize_t char_read(struct file *, char *, size_t, loff_t *);
extern ssize_t block_read(struct file *, char *, size_t, loff_t *);
extern int read_ahead[];
extern ssize_t char_write(struct file *, const char *, size_t, loff_t *);
extern ssize_t block_write(struct file *, const char *, size_t, loff_t *);
extern int file_fsync(struct file *, struct dentry *, int);
extern int generic_buffer_fdatasync(struct inode *inode, unsigned long start_idx, unsigned long end_idx);
extern int generic_osync_inode(struct inode *, int);
extern int inode_change_ok(struct inode *, struct iattr *);
extern void inode_setattr(struct inode *, struct iattr *);
/*
* Common dentry functions for inclusion in the VFS
* or in other stackable file systems. Some of these
* functions were in linux/fs/ C (VFS) files.
*
*/
/*
* Locking the parent is needed to:
* - serialize directory operations
* - make sure the parent doesn't change from
* under us in the middle of an operation.
*
* NOTE! Right now we'd rather use a "struct inode"
* for this, but as I expect things to move toward
* using dentries instead for most things it is
* probably better to start with the conceptually
* better interface of relying on a path of dentries.
*/
static inline struct dentry *lock_parent(struct dentry *dentry)
{
struct dentry *dir = dget(dentry->d_parent);
down(&dir->d_inode->i_sem);
return dir;
}
static inline struct dentry *get_parent(struct dentry *dentry)
{
return dget(dentry->d_parent);
}
static inline void unlock_dir(struct dentry *dir)
{
up(&dir->d_inode->i_sem);
dput(dir);
}
/*
* Whee.. Deadlock country. Happily there are only two VFS
* operations that does this..
*/
static inline void double_down(struct semaphore *s1, struct semaphore *s2)
{
if (s1 != s2) {
if ((unsigned long) s1 < (unsigned long) s2) {
struct semaphore *tmp = s2;
s2 = s1; s1 = tmp;
}
down(s1);
}
down(s2);
}
/*
* Ewwwwwwww... _triple_ lock. We are guaranteed that the 3rd argument is
* not equal to 1st and not equal to 2nd - the first case (target is parent of
* source) would be already caught, the second is plain impossible (target is
* its own parent and that case would be caught even earlier). Very messy.
* I _think_ that it works, but no warranties - please, look it through.
* Pox on bloody lusers who mandated overwriting rename() for directories...
*/
static inline void triple_down(struct semaphore *s1,
struct semaphore *s2,
struct semaphore *s3)
{
if (s1 != s2) {
if ((unsigned long) s1 < (unsigned long) s2) {
if ((unsigned long) s1 < (unsigned long) s3) {
struct semaphore *tmp = s3;
s3 = s1; s1 = tmp;
}
if ((unsigned long) s1 < (unsigned long) s2) {
struct semaphore *tmp = s2;
s2 = s1; s1 = tmp;
}
} else {
if ((unsigned long) s1 < (unsigned long) s3) {
struct semaphore *tmp = s3;
s3 = s1; s1 = tmp;
}
if ((unsigned long) s2 < (unsigned long) s3) {
struct semaphore *tmp = s3;
s3 = s2; s2 = tmp;
}
}
down(s1);
} else if ((unsigned long) s2 < (unsigned long) s3) {
struct semaphore *tmp = s3;
s3 = s2; s2 = tmp;
}
down(s2);
down(s3);
}
static inline void double_up(struct semaphore *s1, struct semaphore *s2)
{
up(s1);
if (s1 != s2)
up(s2);
}
static inline void triple_up(struct semaphore *s1,
struct semaphore *s2,
struct semaphore *s3)
{
up(s1);
if (s1 != s2)
up(s2);
up(s3);
}
static inline void double_lock(struct dentry *d1, struct dentry *d2)
{
double_down(&d1->d_inode->i_sem, &d2->d_inode->i_sem);
}
static inline void double_unlock(struct dentry *d1, struct dentry *d2)
{
double_up(&d1->d_inode->i_sem,&d2->d_inode->i_sem);
dput(d1);
dput(d2);
}
#endif /* __KERNEL__ */
#endif /* _LINUX_FS_H */
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