thin-provisioning-tools/metadata_checker.cc
2011-12-15 19:34:31 +01:00

185 lines
5.4 KiB
C++

// Copyright (C) 2011 Red Hat, Inc. All rights reserved.
//
// This file is part of the thin-provisioning-tools source.
//
// thin-provisioning-tools is free software: you can redistribute it
// and/or modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation, either version 3 of
// the License, or (at your option) any later version.
//
// thin-provisioning-tools is distributed in the hope that it will be
// useful, but WITHOUT ANY WARRANTY; without even the implied warranty
// of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with thin-provisioning-tools. If not, see
// <http://www.gnu.org/licenses/>.
#include "metadata_checker.h"
using namespace thin_provisioning;
//----------------------------------------------------------------
namespace {
// As well as the standard btree checks, we build up a set of what
// devices having mappings defined, which can later be cross
// referenced with the details tree. A separate block_counter is
// used to later verify the data space map.
class mapping_validator : public btree_checker<2, block_traits> {
public:
typedef boost::shared_ptr<mapping_validator> ptr;
mapping_validator(block_counter &metadata_counter, block_counter &data_counter)
: btree_checker<2, block_traits>(metadata_counter),
data_counter_(data_counter) {
}
// Sharing can only occur in level 1 nodes.
// FIXME: not true once we start having held roots.
bool visit_internal_leaf(unsigned level,
bool sub_root,
optional<uint64_t> key,
btree_detail::node_ref<uint64_traits> const &n) {
bool r = btree_checker<2, block_traits>::visit_internal_leaf(level, sub_root, key, n);
if (!r && level == 0) {
throw runtime_error("unexpected sharing in level 0 of mapping tree.");
}
for (unsigned i = 0; i < n.get_nr_entries(); i++)
devices_.insert(n.key_at(i));
return r;
}
bool visit_leaf(unsigned level,
bool sub_root,
optional<uint64_t> key,
btree_detail::node_ref<block_traits> const &n) {
bool r = btree_checker<2, block_traits>::visit_leaf(level, sub_root, key, n);
if (r)
for (unsigned i = 0; i < n.get_nr_entries(); i++)
data_counter_.inc(n.value_at(i).block_);
return r;
}
set<uint64_t> const &get_devices() const {
return devices_;
}
private:
block_counter &data_counter_;
set<uint64_t> devices_;
};
class details_validator : public btree_checker<1, device_details_traits> {
public:
typedef boost::shared_ptr<details_validator> ptr;
details_validator(block_counter &counter)
: btree_checker<1, device_details_traits>(counter) {
}
bool visit_leaf(unsigned level,
bool sub_root,
optional<uint64_t> key,
btree_detail::node_ref<device_details_traits> const &n) {
bool r = btree_checker<1, device_details_traits>::visit_leaf(level, sub_root, key, n);
if (r)
for (unsigned i = 0; i < n.get_nr_entries(); i++)
devices_.insert(n.key_at(i));
return r;
}
set<uint64_t> const &get_devices() const {
return devices_;
}
private:
set<uint64_t> devices_;
};
struct check_count : public space_map::iterator {
check_count(string const &desc, block_counter const &expected)
: bad_(false),
expected_(expected),
errors_(new error_set(desc)) {
}
virtual void operator() (block_address b, ref_t actual) {
ref_t expected = expected_.get_count(b);
if (actual != expected) {
ostringstream out;
out << b << ": was " << actual
<< ", expected " << expected;
errors_->add_child(out.str());
bad_ = true;
}
}
bool bad_;
block_counter const &expected_;
error_set::ptr errors_;
};
optional<error_set::ptr>
check_ref_counts(string const &desc, block_counter const &counts,
space_map::ptr sm) {
check_count checker(desc, counts);
sm->iterate(checker);
return checker.bad_ ? optional<error_set::ptr>(checker.errors_) : optional<error_set::ptr>();
}
}
//----------------------------------------------------------------
boost::optional<error_set::ptr>
thin_provisioning::metadata_check(metadata::ptr md)
{
error_set::ptr errors(new error_set("Errors in metadata"));
block_counter metadata_counter, data_counter;
mapping_validator::ptr mv(new mapping_validator(metadata_counter,
data_counter));
md->mappings_->visit(mv);
set<uint64_t> const &mapped_devs = mv->get_devices();
details_validator::ptr dv(new details_validator(metadata_counter));
md->details_->visit(dv);
set<uint64_t> const &details_devs = dv->get_devices();
for (set<uint64_t>::const_iterator it = mapped_devs.begin(); it != mapped_devs.end(); ++it)
if (details_devs.count(*it) == 0) {
ostringstream out;
out << "mapping exists for device " << *it
<< ", yet there is no entry in the details tree.";
throw runtime_error(out.str());
}
metadata_counter.inc(SUPERBLOCK_LOCATION);
md->metadata_sm_->check(metadata_counter);
md->data_sm_->check(metadata_counter);
errors->add_child(check_ref_counts("Errors in metadata block reference counts",
metadata_counter, md->metadata_sm_));
errors->add_child(check_ref_counts("Errors in data block reference counts",
data_counter, md->data_sm_));
return (errors->get_children().size() > 0) ?
optional<error_set::ptr>(errors) :
optional<error_set::ptr>();
}
//----------------------------------------------------------------