Commit e0f9396e authored by Al Viro's avatar Al Viro
Browse files

propagate_one(): separate the "what should be the master for this copy" part 



When we create the first copy for a peer group, it becomes a slave of
one of the existing copies; take that logics into a separate helper -
find_master(parent, last_copy, original).

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 15e710b8

fs/pnode.c

+26 −17
Original line number Diff line number Diff line
@@ -232,6 +232,31 @@ static bool need_secondary(struct mount *m, struct mountpoint *dest_mp) 
	return true;

}



static struct mount *find_master(struct mount *m,

				struct mount *last_copy,

				struct mount *original)

{

	struct mount *p;



	// ascend until there's a copy for something with the same master

	for (;;) {

		p = m->mnt_master;

		if (!p || IS_MNT_MARKED(p))

			break;

		m = p;

	}

	while (!peers(last_copy, original)) {

		struct mount *parent = last_copy->mnt_parent;

		if (parent->mnt_master == p) {

			if (!peers(parent, m))

				last_copy = last_copy->mnt_master;

			break;

		}

		last_copy = last_copy->mnt_master;

	}

	return last_copy;

}



static int propagate_one(struct mount *m, struct mountpoint *dest_mp)

{

	struct mount *child;
@@ -240,23 +265,7 @@ static int propagate_one(struct mount *m, struct mountpoint *dest_mp) 
	if (peers(m, last_dest)) {

		type = CL_MAKE_SHARED;

	} else {

		struct mount *n, *p;

		bool done;

		for (n = m; ; n = p) {

			p = n->mnt_master;

			if (!p || IS_MNT_MARKED(p))

				break;

		}

		do {

			struct mount *parent = last_source->mnt_parent;

			if (peers(last_source, first_source))

				break;

			done = parent->mnt_master == p;

			if (done && peers(n, parent))

				break;

			last_source = last_source->mnt_master;

		} while (!done);



		last_source = find_master(m, last_source, first_source);

		type = CL_SLAVE;

		/* beginning of peer group among the slaves? */

		if (IS_MNT_SHARED(m))