thin-provisioning-tools/persistent-data/block.tcc
Ming-Hung Tsai b7d418131d Spin-off syscall-related file operations (#78)
* [file_utils] spin-off syscall-related file operations

1. Eliminate the potential circular dependency between
   persistent-data/block.h and persistent-data/file_utils.h,
   if the former one wants to include the latter.
2. Avoid namespace pollution by removing the "using namespace std"
   declaration in block.tcc.
3. Correct the header hierarchy: base/xml_utils.h now no longer
   depends on the higher-level persistent-data/file_utils.h

* [file_utils] support block files in get_file_length()
2017-04-29 18:51:52 +01:00

242 lines
6.2 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 "block.h"
#include "base/error_string.h"
#include "base/file_utils.h"
#include "block-cache/io_engine.h"
#include <boost/bind.hpp>
#include <stdexcept>
//----------------------------------------------------------------
namespace persistent_data {
template <uint32_t BlockSize>
block_manager<BlockSize>::read_ref::read_ref(block_cache::block &b)
: b_(b)
{
}
template <uint32_t BlockSize>
block_manager<BlockSize>::read_ref::read_ref(read_ref const &rhs)
: b_(rhs.b_)
{
b_.get();
}
template <uint32_t BlockSize>
block_manager<BlockSize>::read_ref::~read_ref()
{
b_.put();
}
template <uint32_t BlockSize>
typename block_manager<BlockSize>::read_ref const &
block_manager<BlockSize>::read_ref::operator =(read_ref const &rhs)
{
if (this != &rhs) {
b_ = rhs.b_;
b_.get();
}
return *this;
}
template <uint32_t BlockSize>
block_address
block_manager<BlockSize>::read_ref::get_location() const
{
return b_.get_index();
}
template <uint32_t BlockSize>
void const *
block_manager<BlockSize>::read_ref::data() const
{
return b_.get_data();
}
//--------------------------------
template <uint32_t BlockSize>
block_manager<BlockSize>::write_ref::write_ref(block_cache::block &b)
: read_ref(b),
ref_count_(NULL)
{
}
template <uint32_t BlockSize>
block_manager<BlockSize>::write_ref::write_ref(block_cache::block &b, unsigned &ref_count)
: read_ref(b),
ref_count_(&ref_count) {
if (*ref_count_)
throw std::runtime_error("superblock already locked");
(*ref_count_)++;
}
template <uint32_t BlockSize>
block_manager<BlockSize>::write_ref::write_ref(write_ref const &rhs)
: read_ref(rhs),
ref_count_(rhs.ref_count_) {
if (ref_count_)
(*ref_count_)++;
}
template <uint32_t BlockSize>
block_manager<BlockSize>::write_ref::~write_ref()
{
if (ref_count_) {
if (!*ref_count_) {
std::cerr << "write_ref ref_count going below zero";
::exit(1);
}
(*ref_count_)--;
}
}
template <uint32_t BlockSize>
typename block_manager<BlockSize>::write_ref const &
block_manager<BlockSize>::write_ref::operator =(write_ref const &rhs)
{
if (&rhs != this) {
read_ref::operator =(rhs);
ref_count_ = rhs.ref_count_;
if (ref_count_)
(*ref_count_)++;
}
}
template <uint32_t BlockSize>
void *
block_manager<BlockSize>::write_ref::data()
{
return read_ref::b_.get_data();
}
//----------------------------------------------------------------
template <uint32_t BlockSize>
block_manager<BlockSize>::block_manager(std::string const &path,
block_address nr_blocks,
unsigned max_concurrent_blocks,
mode m,
bool excl)
// FIXME: * BlockSize ?
: fd_(open_or_create_block_file(path, nr_blocks * BlockSize, m, excl)),
bc_(fd_, BlockSize >> SECTOR_SHIFT, nr_blocks, 1024u * 1024u * 16),
superblock_ref_count_(0)
{
}
template <uint32_t BlockSize>
int
block_manager<BlockSize>::open_or_create_block_file(std::string const &path, off_t file_size, mode m, bool excl)
{
switch (m) {
case READ_ONLY:
return file_utils::open_block_file(path, file_size, false, excl);
case READ_WRITE:
return file_utils::open_block_file(path, file_size, true, excl);
case CREATE:
return file_utils::create_block_file(path, file_size);
default:
throw std::runtime_error("unsupported mode");
}
}
template <uint32_t BlockSize>
typename block_manager<BlockSize>::read_ref
block_manager<BlockSize>::read_lock(block_address location,
typename bcache::validator::ptr v) const
{
block_cache::block &b = bc_.get(location, 0, v);
return read_ref(b);
}
template <uint32_t BlockSize>
typename block_manager<BlockSize>::write_ref
block_manager<BlockSize>::write_lock(block_address location,
typename bcache::validator::ptr v)
{
block_cache::block &b = bc_.get(location, block_cache::GF_DIRTY, v);
return write_ref(b);
}
template <uint32_t BlockSize>
typename block_manager<BlockSize>::write_ref
block_manager<BlockSize>::write_lock_zero(block_address location,
typename bcache::validator::ptr v)
{
block_cache::block &b = bc_.get(location, block_cache::GF_ZERO, v);
return write_ref(b);
}
template <uint32_t BlockSize>
typename block_manager<BlockSize>::write_ref
block_manager<BlockSize>::superblock(block_address location,
typename bcache::validator::ptr v)
{
if (bc_.get_nr_locked() > 0)
throw std::runtime_error("attempt to lock superblock while other locks are still held");
block_cache::block &b = bc_.get(location, block_cache::GF_DIRTY | block_cache::GF_BARRIER, v);
return write_ref(b, superblock_ref_count_);
}
template <uint32_t BlockSize>
typename block_manager<BlockSize>::write_ref
block_manager<BlockSize>::superblock_zero(block_address location,
typename bcache::validator::ptr v)
{
if (bc_.get_nr_locked() > 0)
throw std::runtime_error("attempt to lock superblock while other locks are still held");
block_cache::block &b = bc_.get(location, block_cache::GF_ZERO | block_cache::GF_BARRIER, v);
return write_ref(b, superblock_ref_count_);
}
template <uint32_t BlockSize>
block_address
block_manager<BlockSize>::get_nr_blocks() const
{
return bc_.get_nr_blocks();
}
template <uint32_t BlockSize>
void
block_manager<BlockSize>::prefetch(block_address b) const
{
bc_.prefetch(b);
}
template <uint32_t BlockSize>
void
block_manager<BlockSize>::flush() const
{
bc_.flush();
}
}
//----------------------------------------------------------------