From 419148da6e76dd0d379b5ec33c461cee1015322e Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 24 Nov 2011 19:41:16 -0500 Subject: vfs: spread struct mount - attach_mnt/detach_mnt Signed-off-by: Al Viro --- fs/namespace.c | 41 ++++++++++++++++++++++------------------- 1 file changed, 22 insertions(+), 19 deletions(-) (limited to 'fs/namespace.c') diff --git a/fs/namespace.c b/fs/namespace.c index 7226dc514b3b..444557e04b38 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -556,14 +556,14 @@ static void dentry_reset_mounted(struct dentry *dentry) /* * vfsmount lock must be held for write */ -static void detach_mnt(struct vfsmount *mnt, struct path *old_path) -{ - old_path->dentry = mnt->mnt_mountpoint; - old_path->mnt = mnt->mnt_parent; - mnt->mnt_parent = mnt; - mnt->mnt_mountpoint = mnt->mnt_root; - list_del_init(&mnt->mnt_child); - list_del_init(&mnt->mnt_hash); +static void detach_mnt(struct mount *mnt, struct path *old_path) +{ + old_path->dentry = mnt->mnt.mnt_mountpoint; + old_path->mnt = mnt->mnt.mnt_parent; + mnt->mnt.mnt_parent = &mnt->mnt; + mnt->mnt.mnt_mountpoint = mnt->mnt.mnt_root; + list_del_init(&mnt->mnt.mnt_child); + list_del_init(&mnt->mnt.mnt_hash); dentry_reset_mounted(old_path->dentry); } @@ -583,12 +583,12 @@ void mnt_set_mountpoint(struct vfsmount *mnt, struct dentry *dentry, /* * vfsmount lock must be held for write */ -static void attach_mnt(struct vfsmount *mnt, struct path *path) +static void attach_mnt(struct mount *mnt, struct path *path) { - mnt_set_mountpoint(path->mnt, path->dentry, mnt); - list_add_tail(&mnt->mnt_hash, mount_hashtable + + mnt_set_mountpoint(path->mnt, path->dentry, &mnt->mnt); + list_add_tail(&mnt->mnt.mnt_hash, mount_hashtable + hash(path->mnt, path->dentry)); - list_add_tail(&mnt->mnt_child, &path->mnt->mnt_mounts); + list_add_tail(&mnt->mnt.mnt_child, &path->mnt->mnt_mounts); } static inline void __mnt_make_longterm(struct vfsmount *mnt) @@ -1446,7 +1446,7 @@ struct vfsmount *copy_tree(struct vfsmount *mnt, struct dentry *dentry, goto Enomem; br_write_lock(vfsmount_lock); list_add_tail(&q->mnt_list, &res->mnt_list); - attach_mnt(q, &path); + attach_mnt(real_mount(q), &path); br_write_unlock(vfsmount_lock); } } @@ -1612,8 +1612,8 @@ static int attach_recursive_mnt(struct vfsmount *source_mnt, set_mnt_shared(&p->mnt); } if (parent_path) { - detach_mnt(source_mnt, parent_path); - attach_mnt(source_mnt, path); + detach_mnt(real_mount(source_mnt), parent_path); + attach_mnt(real_mount(source_mnt), path); touch_mnt_namespace(parent_path->mnt->mnt_ns); } else { mnt_set_mountpoint(dest_mnt, dest_dentry, source_mnt); @@ -2600,6 +2600,7 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, const char __user *, put_old) { struct path new, old, parent_path, root_parent, root; + struct mount *new_mnt, *root_mnt; int error; if (!capable(CAP_SYS_ADMIN)) @@ -2623,6 +2624,8 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, goto out3; error = -EINVAL; + new_mnt = real_mount(new.mnt); + root_mnt = real_mount(root.mnt); if (IS_MNT_SHARED(old.mnt) || IS_MNT_SHARED(new.mnt->mnt_parent) || IS_MNT_SHARED(root.mnt->mnt_parent)) @@ -2651,12 +2654,12 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, if (!is_path_reachable(old.mnt, old.dentry, &new)) goto out4; br_write_lock(vfsmount_lock); - detach_mnt(new.mnt, &parent_path); - detach_mnt(root.mnt, &root_parent); + detach_mnt(new_mnt, &parent_path); + detach_mnt(root_mnt, &root_parent); /* mount old root on put_old */ - attach_mnt(root.mnt, &old); + attach_mnt(root_mnt, &old); /* mount new_root on / */ - attach_mnt(new.mnt, &root_parent); + attach_mnt(new_mnt, &root_parent); touch_mnt_namespace(current->nsproxy->mnt_ns); br_write_unlock(vfsmount_lock); chroot_fs_refs(&root, &new); -- cgit v1.2.3