9676f0c638
An unbindable mount does not forward or receive propagation. Also unbindable mount disallows bind mounts. The semantics is as follows. Bind semantics: It is invalid to bind mount an unbindable mount. Move semantics: It is invalid to move an unbindable mount under shared mount. Clone-namespace semantics: If a mount is unbindable in the parent namespace, the corresponding cloned mount in the child namespace becomes unbindable too. Note: there is subtle difference, unbindable mounts cannot be bind mounted but can be cloned during clone-namespace. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
38 lines
1013 B
C
38 lines
1013 B
C
/*
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* linux/fs/pnode.h
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*
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* (C) Copyright IBM Corporation 2005.
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* Released under GPL v2.
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*
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*/
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#ifndef _LINUX_PNODE_H
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#define _LINUX_PNODE_H
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#include <linux/list.h>
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#include <linux/mount.h>
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#define IS_MNT_SHARED(mnt) (mnt->mnt_flags & MNT_SHARED)
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#define IS_MNT_SLAVE(mnt) (mnt->mnt_master)
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#define IS_MNT_NEW(mnt) (!mnt->mnt_namespace)
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#define CLEAR_MNT_SHARED(mnt) (mnt->mnt_flags &= ~MNT_SHARED)
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#define IS_MNT_UNBINDABLE(mnt) (mnt->mnt_flags & MNT_UNBINDABLE)
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#define CL_EXPIRE 0x01
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#define CL_SLAVE 0x02
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#define CL_COPY_ALL 0x04
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#define CL_MAKE_SHARED 0x08
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#define CL_PROPAGATION 0x10
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static inline void set_mnt_shared(struct vfsmount *mnt)
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{
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mnt->mnt_flags &= ~MNT_PNODE_MASK;
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mnt->mnt_flags |= MNT_SHARED;
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}
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void change_mnt_propagation(struct vfsmount *, int);
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int propagate_mnt(struct vfsmount *, struct dentry *, struct vfsmount *,
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struct list_head *);
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int propagate_umount(struct list_head *);
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int propagate_mount_busy(struct vfsmount *, int);
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#endif /* _LINUX_PNODE_H */
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