Commit 8f11538e authored by Al Viro's avatar Al Viro
Browse files

do_add_mount(): lift lock_mount/unlock_mount into callers 



preparation to finish_automount() fix (next commit)

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent bb6d3fb3

fs/namespace.c

+24 −23
Original line number Diff line number Diff line
@@ -2697,45 +2697,32 @@ static int do_move_mount_old(struct path *path, const char *old_name) 
/*

 * add a mount into a namespace's mount tree

 */

static int do_add_mount(struct mount *newmnt, struct path *path, int mnt_flags)

static int do_add_mount(struct mount *newmnt, struct mountpoint *mp,

			struct path *path, int mnt_flags)

{

	struct mountpoint *mp;

	struct mount *parent;

	int err;

	struct mount *parent = real_mount(path->mnt);



	mnt_flags &= ~MNT_INTERNAL_FLAGS;



	mp = lock_mount(path);

	if (IS_ERR(mp))

		return PTR_ERR(mp);



	parent = real_mount(path->mnt);

	err = -EINVAL;

	if (unlikely(!check_mnt(parent))) {

		/* that's acceptable only for automounts done in private ns */

		if (!(mnt_flags & MNT_SHRINKABLE))

			goto unlock;

			return -EINVAL;

		/* ... and for those we'd better have mountpoint still alive */

		if (!parent->mnt_ns)

			goto unlock;

			return -EINVAL;

	}



	/* Refuse the same filesystem on the same mount point */

	err = -EBUSY;

	if (path->mnt->mnt_sb == newmnt->mnt.mnt_sb &&

	    path->mnt->mnt_root == path->dentry)

		goto unlock;

		return -EBUSY;



	err = -EINVAL;

	if (d_is_symlink(newmnt->mnt.mnt_root))

		goto unlock;

		return -EINVAL;



	newmnt->mnt.mnt_flags = mnt_flags;

	err = graft_tree(newmnt, parent, mp);



unlock:

	unlock_mount(mp);

	return err;

	return graft_tree(newmnt, parent, mp);

}



static bool mount_too_revealing(const struct super_block *sb, int *new_mnt_flags);
@@ -2748,6 +2735,7 @@ static int do_new_mount_fc(struct fs_context *fc, struct path *mountpoint, 
			   unsigned int mnt_flags)

{

	struct vfsmount *mnt;

	struct mountpoint *mp;

	struct super_block *sb = fc->root->d_sb;

	int error;
@@ -2768,7 +2756,13 @@ static int do_new_mount_fc(struct fs_context *fc, struct path *mountpoint, 


	mnt_warn_timestamp_expiry(mountpoint, mnt);



	error = do_add_mount(real_mount(mnt), mountpoint, mnt_flags);

	mp = lock_mount(mountpoint);

	if (IS_ERR(mp)) {

		mntput(mnt);

		return PTR_ERR(mp);

	}

	error = do_add_mount(real_mount(mnt), mp, mountpoint, mnt_flags);

	unlock_mount(mp);

	if (error < 0)

		mntput(mnt);

	return error;
@@ -2830,6 +2824,7 @@ static int do_new_mount(struct path *path, const char *fstype, int sb_flags, 
int finish_automount(struct vfsmount *m, struct path *path)

{

	struct mount *mnt = real_mount(m);

	struct mountpoint *mp;

	int err;

	/* The new mount record should have at least 2 refs to prevent it being

	 * expired before we get a chance to add it
@@ -2842,7 +2837,13 @@ int finish_automount(struct vfsmount *m, struct path *path) 
		goto fail;

	}



	err = do_add_mount(mnt, path, path->mnt->mnt_flags | MNT_SHRINKABLE);

	mp = lock_mount(path);

	if (IS_ERR(mp)) {

		err = PTR_ERR(mp);

		goto fail;

	}

	err = do_add_mount(mnt, mp, path, path->mnt->mnt_flags | MNT_SHRINKABLE);

	unlock_mount(mp);

	if (!err)

		return 0;

fail: