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#ifndef _LINUX_FS_STRUCT_H
#define _LINUX_FS_STRUCT_H
#ifdef __KERNEL__
struct fs_struct {
atomic_t count;
rwlock_t lock;
int umask;
struct dentry * root, * pwd, * altroot;
struct vfsmount * rootmnt, * pwdmnt, * altrootmnt;
};
#define INIT_FS { \
ATOMIC_INIT(1), \
RW_LOCK_UNLOCKED, \
0022, \
NULL, NULL, NULL, NULL, NULL, NULL \
}
extern void exit_fs(struct task_struct *);
extern void set_fs_altroot(void);
/*
* Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values.
* It can block. Requires the big lock held.
*/
static inline void set_fs_root(struct fs_struct *fs,
struct vfsmount *mnt,
struct dentry *dentry)
{
struct dentry *old_root;
struct vfsmount *old_rootmnt;
write_lock(&fs->lock);
old_root = fs->root;
old_rootmnt = fs->rootmnt;
fs->rootmnt = mntget(mnt);
fs->root = dget(dentry);
write_unlock(&fs->lock);
if (old_root) {
dput(old_root);
mntput(old_rootmnt);
}
}
/*
* Replace the fs->{pwdmnt,pwd} with {mnt,dentry}. Put the old values.
* It can block. Requires the big lock held.
*/
static inline void set_fs_pwd(struct fs_struct *fs,
struct vfsmount *mnt,
struct dentry *dentry)
{
struct dentry *old_pwd;
struct vfsmount *old_pwdmnt;
write_lock(&fs->lock);
old_pwd = fs->pwd;
old_pwdmnt = fs->pwdmnt;
fs->pwdmnt = mntget(mnt);
fs->pwd = dget(dentry);
write_unlock(&fs->lock);
if (old_pwd) {
dput(old_pwd);
mntput(old_pwdmnt);
}
}
struct fs_struct *copy_fs_struct(struct fs_struct *old);
void put_fs_struct(struct fs_struct *fs);
#endif
#endif
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