emo/thin-provisioning-tools
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[thin_trim] FInally get thin_trim emitting the right discards

Browse Source
This commit is contained in:
Joe Thornber 2016-04-05 12:27:00 +01:00
parent 2288fc4565
commit 866986b883
1 changed files with 34 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

60
thin-provisioning/thin_trim.cc
View File

@ -22,17 +22,6 @@ using namespace thin_provisioning;
//----------------------------------------------------------------
namespace {
void confirm_pool_is_not_active() {
cout << "The pool must *not* be active when running this tool.\n"
<< "Do you wish to continue? [Y/N]\n"
<< endl;
string input;
cin >> input;
if (input != "Y")
exit(0);
}
class discard_emitter {
public:
discard_emitter(string const &data_dev, unsigned block_size, uint64_t nr_blocks)
@ -50,6 +39,8 @@ namespace {
range[0] = block_to_byte(b);
range[1] = block_to_byte(e) - range[0];
cerr << "emitting discard for blocks (" << b << ", " << e << "]\n";
if (ioctl(fd_, BLKDISCARD, &range))
throw runtime_error("discard ioctl failed");
}
@ -98,43 +89,57 @@ namespace {
unsigned block_size_;
};
class trim_visitor : public space_map_detail::visitor {
class trim_iterator : public space_map::iterator {
public:
trim_visitor(discard_emitter &e)
trim_iterator(discard_emitter &e)
: emitter_(e) {
}
virtual void visit(space_map_detail::missing_counts const &mc) {
throw std::runtime_error("corrupt metadata, please use thin_check for details");
virtual void operator() (block_address b, ref_t count) {
highest_ = b;
if (count) {
if (last_referenced_ && (b > *last_referenced_ + 1))
emitter_.emit(*last_referenced_ + 1, b);
last_referenced_ = b;
}
}
virtual void visit(block_address b, uint32_t count) {
if (last_visited_ && (b > *last_visited_ + 1))
emitter_.emit(*last_visited_ + 1, b);
void complete() {
if (last_referenced_) {
if (*last_referenced_ != *highest_)
emitter_.emit(*last_referenced_, *highest_ + 1ull);
last_visited_ = b;
} else if (highest_)
emitter_.emit(0ull, *highest_ + 1);
}
private:
discard_emitter &emitter_;
boost::optional<block_address> last_visited_;
boost::optional<block_address> last_referenced_;
boost::optional<block_address> highest_;
};
int trim(string const &metadata_dev, string const &data_dev) {
cerr << "in trim\n";
// We can trim any block that has zero count in the data
// space map.
block_manager<>::ptr bm = open_bm(metadata_dev, block_manager<>::READ_ONLY);
metadata md(bm);
if (!md.data_sm_->get_nr_free())
if (!md.data_sm_->get_nr_free()) {
cerr << "All data blocks allocated, nothing to discard\n";
return 0;
}
discard_emitter de(data_dev, md.sb_.data_block_size_,
md.data_sm_->get_nr_blocks());
trim_visitor tv(de);
trim_iterator ti(de);
confirm_pool_is_not_active();
md.data_sm_->visit(tv);
md.data_sm_->iterate(ti);
ti.complete();
return 0;
}
@ -155,9 +160,8 @@ thin_trim_cmd::thin_trim_cmd()
void
thin_trim_cmd::usage(std::ostream &out) const
{
out << "Usage: " << get_name() << " [options] {device|file}\n"
out << "Usage: " << get_name() << " [options] --metadata-dev {device|file} --data-dev {device|file}\n"
<< "Options:\n"
<< " {--pool-inactive}\n"
<< " {-h|--help}\n"
<< " {-V|--version}" << endl;
}
@ -188,6 +192,10 @@ thin_trim_cmd::run(int argc, char **argv)
fs.data_dev = optarg;
break;
case 2:
cerr << "--pool-inactive no longer required since we ensure the metadata device is opened exclusively.\n";
break;
case 'h':
usage(cout);
return 0;