linux/fs/internal.h
Al Viro 498052bba5 New locking/refcounting for fs_struct
* all changes of current->fs are done under task_lock and write_lock of
  old fs->lock
* refcount is not atomic anymore (same protection)
* its decrements are done when removing reference from current; at the
  same time we decide whether to free it.
* put_fs_struct() is gone
* new field - ->in_exec.  Set by check_unsafe_exec() if we are trying to do
  execve() and only subthreads share fs_struct.  Cleared when finishing exec
  (success and failure alike).  Makes CLONE_FS fail with -EAGAIN if set.
* check_unsafe_exec() may fail with -EAGAIN if another execve() from subthread
  is in progress.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-31 23:00:26 -04:00

68 lines
1.6 KiB
C

/* fs/ internal definitions
*
* Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
struct super_block;
struct linux_binprm;
struct path;
/*
* block_dev.c
*/
#ifdef CONFIG_BLOCK
extern struct super_block *blockdev_superblock;
extern void __init bdev_cache_init(void);
static inline int sb_is_blkdev_sb(struct super_block *sb)
{
return sb == blockdev_superblock;
}
#else
static inline void bdev_cache_init(void)
{
}
static inline int sb_is_blkdev_sb(struct super_block *sb)
{
return 0;
}
#endif
/*
* char_dev.c
*/
extern void __init chrdev_init(void);
/*
* exec.c
*/
extern int check_unsafe_exec(struct linux_binprm *);
/*
* namespace.c
*/
extern int copy_mount_options(const void __user *, unsigned long *);
extern void free_vfsmnt(struct vfsmount *);
extern struct vfsmount *alloc_vfsmnt(const char *);
extern struct vfsmount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
struct vfsmount *);
extern void release_mounts(struct list_head *);
extern void umount_tree(struct vfsmount *, int, struct list_head *);
extern struct vfsmount *copy_tree(struct vfsmount *, struct dentry *, int);
extern void __init mnt_init(void);
/*
* fs_struct.c
*/
extern void chroot_fs_refs(struct path *, struct path *);