499 lines
12 KiB
C++
499 lines
12 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 <errno.h>
|
|
#include <fcntl.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <string.h>
|
|
|
|
#include <boost/bind.hpp>
|
|
#include <stdexcept>
|
|
#include <sstream>
|
|
|
|
// FIXME: remove these from a header!
|
|
using namespace boost;
|
|
using namespace persistent_data;
|
|
using namespace std;
|
|
|
|
//----------------------------------------------------------------
|
|
|
|
namespace {
|
|
using namespace std;
|
|
|
|
int const DEFAULT_MODE = 0666;
|
|
int const OPEN_FLAGS = O_DIRECT | O_SYNC;
|
|
|
|
// FIXME: introduce a new exception for this, or at least lift this
|
|
// to exception.h
|
|
void syscall_failed(char const *call) {
|
|
char buffer[128];
|
|
char *msg = strerror_r(errno, buffer, sizeof(buffer));
|
|
|
|
ostringstream out;
|
|
out << "syscall '" << call << "' failed: " << msg;
|
|
throw runtime_error(out.str());
|
|
}
|
|
|
|
int open_file(string const &path, int flags) {
|
|
int fd = ::open(path.c_str(), OPEN_FLAGS | flags, DEFAULT_MODE);
|
|
if (fd < 0)
|
|
syscall_failed("open");
|
|
|
|
return fd;
|
|
}
|
|
|
|
bool file_exists(string const &path) {
|
|
typename ::stat info;
|
|
|
|
int r = ::stat(path.c_str(), &info);
|
|
if (r) {
|
|
if (errno == ENOENT)
|
|
return false;
|
|
|
|
syscall_failed("stat");
|
|
return false; // never get here
|
|
|
|
} else
|
|
return S_ISREG(info.st_mode) || S_ISBLK(info.st_mode);
|
|
}
|
|
|
|
int create_block_file(string const &path, off_t file_size) {
|
|
if (file_exists(path)) {
|
|
ostringstream out;
|
|
out << __FUNCTION__ << ": file '" << path << "' already exists";
|
|
throw runtime_error(out.str());
|
|
}
|
|
|
|
int fd = open_file(path, O_CREAT | O_RDWR);
|
|
|
|
// fallocate didn't seem to work
|
|
int r = ::lseek(fd, file_size, SEEK_SET);
|
|
if (r < 0)
|
|
syscall_failed("lseek");
|
|
|
|
return fd;
|
|
}
|
|
|
|
int open_block_file(string const &path, off_t min_size, bool writeable) {
|
|
if (!file_exists(path)) {
|
|
ostringstream out;
|
|
out << __FUNCTION__ << ": file '" << path << "' doesn't exist";
|
|
throw runtime_error(out.str());
|
|
}
|
|
|
|
return open_file(path, writeable ? O_RDWR : O_RDONLY);
|
|
}
|
|
};
|
|
|
|
template <uint32_t BlockSize>
|
|
block_io<BlockSize>::block_io(std::string const &path, block_address nr_blocks, mode m)
|
|
: nr_blocks_(nr_blocks),
|
|
mode_(m)
|
|
{
|
|
off_t file_size = nr_blocks * BlockSize;
|
|
|
|
switch (m) {
|
|
case READ_ONLY:
|
|
fd_ = open_block_file(path, file_size, false);
|
|
break;
|
|
|
|
case READ_WRITE:
|
|
fd_ = open_block_file(path, file_size, true);
|
|
break;
|
|
|
|
case CREATE:
|
|
fd_ = create_block_file(path, file_size);
|
|
break;
|
|
|
|
default:
|
|
throw runtime_error("unsupported mode");
|
|
}
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
block_io<BlockSize>::~block_io()
|
|
{
|
|
if (::close(fd_) < 0)
|
|
syscall_failed("close");
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
void
|
|
block_io<BlockSize>::read_buffer(block_address location, buffer<BlockSize> &buffer) const
|
|
{
|
|
off_t r;
|
|
r = ::lseek(fd_, BlockSize * location, SEEK_SET);
|
|
if (r == (off_t) -1)
|
|
throw std::runtime_error("lseek failed");
|
|
|
|
ssize_t n;
|
|
size_t remaining = BlockSize;
|
|
unsigned char *buf = buffer.raw();
|
|
do {
|
|
n = ::read(fd_, buf, remaining);
|
|
if (n > 0) {
|
|
remaining -= n;
|
|
buf += n;
|
|
}
|
|
} while (remaining && ((n > 0) || (n == EINTR) || (n == EAGAIN)));
|
|
|
|
if (n < 0)
|
|
throw std::runtime_error("read failed");
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
void
|
|
block_io<BlockSize>::write_buffer(block_address location, buffer<BlockSize> const &buffer)
|
|
{
|
|
off_t r;
|
|
r = ::lseek(fd_, BlockSize * location, SEEK_SET);
|
|
if (r == (off_t) -1)
|
|
throw std::runtime_error("lseek failed");
|
|
|
|
ssize_t n;
|
|
size_t remaining = BlockSize;
|
|
unsigned char const *buf = buffer.raw();
|
|
do {
|
|
n = ::write(fd_, buf, remaining);
|
|
if (n > 0) {
|
|
remaining -= n;
|
|
buf += n;
|
|
}
|
|
} while (remaining && ((n > 0) || (n == EINTR) || (n == EAGAIN)));
|
|
|
|
if (n < 0) {
|
|
std::ostringstream out;
|
|
out << "write failed to block " << location
|
|
<< ", block size = " << BlockSize
|
|
<< ", remaining = " << remaining
|
|
<< ", n = " << n
|
|
<< ", errno = " << errno
|
|
<< ", fd_ = " << fd_
|
|
<< std::endl;
|
|
throw std::runtime_error(out.str());
|
|
}
|
|
}
|
|
|
|
//----------------------------------------------------------------
|
|
|
|
template <uint32_t BlockSize>
|
|
block_manager<BlockSize>::block::block(typename block_io<BlockSize>::ptr io,
|
|
block_address location,
|
|
block_type bt,
|
|
typename validator::ptr v,
|
|
bool zero)
|
|
: io_(io),
|
|
location_(location),
|
|
data_(new buffer<BlockSize>()),
|
|
validator_(v),
|
|
bt_(bt),
|
|
dirty_(false)
|
|
{
|
|
if (zero) {
|
|
memset(data_->raw(), 0, BlockSize);
|
|
dirty_ = true;
|
|
} else {
|
|
io_->read_buffer(location_, *data_);
|
|
validator_->check(*data_, location_);
|
|
}
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
block_manager<BlockSize>::block::~block()
|
|
{
|
|
flush();
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
void
|
|
block_manager<BlockSize>::block::flush()
|
|
{
|
|
if (dirty_) {
|
|
validator_->prepare(*data_, location_);
|
|
io_->write_buffer(location_, *data_);
|
|
}
|
|
}
|
|
|
|
//----------------------------------------------------------------
|
|
|
|
template <uint32_t BlockSize>
|
|
block_manager<BlockSize>::read_ref::read_ref(block_manager<BlockSize> const &bm,
|
|
typename block::ptr b)
|
|
: bm_(&bm),
|
|
block_(b),
|
|
holders_(new unsigned)
|
|
{
|
|
*holders_ = 1;
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
block_manager<BlockSize>::read_ref::read_ref(read_ref const &rhs)
|
|
: bm_(rhs.bm_),
|
|
block_(rhs.block_),
|
|
holders_(rhs.holders_)
|
|
{
|
|
(*holders_)++;
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
block_manager<BlockSize>::read_ref::~read_ref()
|
|
{
|
|
if (!--(*holders_)) {
|
|
if (block_->bt_ == BT_SUPERBLOCK) {
|
|
bm_->flush();
|
|
bm_->cache_.put(block_);
|
|
bm_->flush();
|
|
} else
|
|
bm_->cache_.put(block_);
|
|
|
|
bm_->tracker_.unlock(block_->location_);
|
|
delete holders_;
|
|
}
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
typename block_manager<BlockSize>::read_ref const &
|
|
block_manager<BlockSize>::read_ref::operator =(read_ref const &rhs)
|
|
{
|
|
if (this != &rhs) {
|
|
block_ = rhs.block_;
|
|
bm_ = rhs.bm_;
|
|
holders_ = rhs.holders_;
|
|
(*holders_)++;
|
|
}
|
|
|
|
return *this;
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
block_address
|
|
block_manager<BlockSize>::read_ref::get_location() const
|
|
{
|
|
return block_->location_;
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
buffer<BlockSize> const &
|
|
block_manager<BlockSize>::read_ref::data() const
|
|
{
|
|
return *block_->data_;
|
|
}
|
|
|
|
//--------------------------------
|
|
|
|
template <uint32_t BlockSize>
|
|
block_manager<BlockSize>::write_ref::write_ref(block_manager<BlockSize> const &bm,
|
|
typename block::ptr b)
|
|
: read_ref(bm, b)
|
|
{
|
|
b->dirty_ = true;
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
buffer<BlockSize> &
|
|
block_manager<BlockSize>::write_ref::data()
|
|
{
|
|
return *read_ref::block_->data_;
|
|
}
|
|
|
|
//----------------------------------------------------------------
|
|
|
|
template <uint32_t BlockSize>
|
|
block_manager<BlockSize>::block_manager(std::string const &path,
|
|
block_address nr_blocks,
|
|
unsigned max_concurrent_blocks,
|
|
typename block_io<BlockSize>::mode mode)
|
|
: io_(new block_io<BlockSize>(path, nr_blocks, mode)),
|
|
cache_(max(64u, max_concurrent_blocks)),
|
|
tracker_(0, nr_blocks)
|
|
{
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
typename block_manager<BlockSize>::read_ref
|
|
block_manager<BlockSize>::read_lock(block_address location,
|
|
typename block_manager<BlockSize>::validator::ptr v) const
|
|
{
|
|
tracker_.read_lock(location);
|
|
try {
|
|
check(location);
|
|
boost::optional<typename block::ptr> cached_block = cache_.get(location);
|
|
|
|
if (cached_block) {
|
|
(*cached_block)->check_read_lockable();
|
|
return read_ref(*this, *cached_block);
|
|
}
|
|
|
|
typename block::ptr b(new block(io_, location, BT_NORMAL, v));
|
|
cache_.insert(b);
|
|
return read_ref(*this, b);
|
|
|
|
} catch (...) {
|
|
tracker_.unlock(location);
|
|
throw;
|
|
}
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
typename block_manager<BlockSize>::write_ref
|
|
block_manager<BlockSize>::write_lock(block_address location,
|
|
typename block_manager<BlockSize>::validator::ptr v)
|
|
{
|
|
tracker_.write_lock(location);
|
|
try {
|
|
check(location);
|
|
|
|
boost::optional<typename block::ptr> cached_block = cache_.get(location);
|
|
|
|
if (cached_block) {
|
|
(*cached_block)->check_write_lockable();
|
|
return write_ref(*this, *cached_block);
|
|
}
|
|
|
|
typename block::ptr b(new block(io_, location, BT_NORMAL, v));
|
|
cache_.insert(b);
|
|
return write_ref(*this, b);
|
|
|
|
} catch (...) {
|
|
tracker_.unlock(location);
|
|
throw;
|
|
}
|
|
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
typename block_manager<BlockSize>::write_ref
|
|
block_manager<BlockSize>::write_lock_zero(block_address location,
|
|
typename block_manager<BlockSize>::validator::ptr v)
|
|
{
|
|
tracker_.write_lock(location);
|
|
try {
|
|
check(location);
|
|
|
|
boost::optional<typename block::ptr> cached_block = cache_.get(location);
|
|
if (cached_block) {
|
|
(*cached_block)->check_write_lockable();
|
|
memset((*cached_block)->data_->raw(), 0, BlockSize);
|
|
return write_ref(*this, *cached_block);
|
|
}
|
|
|
|
typename block::ptr b(new block(io_, location, BT_NORMAL, v, true));
|
|
cache_.insert(b);
|
|
return write_ref(*this, b);
|
|
|
|
} catch (...) {
|
|
tracker_.unlock(location);
|
|
throw;
|
|
}
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
typename block_manager<BlockSize>::write_ref
|
|
block_manager<BlockSize>::superblock(block_address location,
|
|
typename block_manager<BlockSize>::validator::ptr v)
|
|
{
|
|
tracker_.superblock_lock(location);
|
|
try {
|
|
check(location);
|
|
|
|
boost::optional<typename block::ptr> cached_block = cache_.get(location);
|
|
|
|
if (cached_block) {
|
|
(*cached_block)->check_write_lockable();
|
|
(*cached_block)->bt_ = BT_SUPERBLOCK;
|
|
(*cached_block)->validator_ = v;
|
|
return write_ref(*this, *cached_block);
|
|
}
|
|
|
|
typename block::ptr b(new block(io_, location, BT_SUPERBLOCK, v));
|
|
cache_.insert(b);
|
|
return write_ref(*this, b);
|
|
|
|
} catch (...) {
|
|
tracker_.unlock(location);
|
|
throw;
|
|
}
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
typename block_manager<BlockSize>::write_ref
|
|
block_manager<BlockSize>::superblock_zero(block_address location,
|
|
typename block_manager<BlockSize>::validator::ptr v)
|
|
{
|
|
tracker_.superblock_lock(location);
|
|
try {
|
|
check(location);
|
|
|
|
boost::optional<typename block::ptr> cached_block = cache_.get(location);
|
|
|
|
if (cached_block) {
|
|
(*cached_block)->check_write_lockable();
|
|
memset((*cached_block)->data_->raw(), 0, BlockSize); // FIXME: add a zero method to buffer
|
|
(*cached_block)->validator_ = v;
|
|
return write_ref(*this, *cached_block);
|
|
}
|
|
|
|
typename block::ptr b(new block(io_, location, BT_SUPERBLOCK,
|
|
mk_validator(new noop_validator), true));
|
|
b->validator_ = v;
|
|
cache_.insert(b);
|
|
return write_ref(*this, b);
|
|
|
|
} catch (...) {
|
|
tracker_.unlock(location);
|
|
throw;
|
|
}
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
void
|
|
block_manager<BlockSize>::check(block_address b) const
|
|
{
|
|
if (b >= io_->get_nr_blocks())
|
|
throw std::runtime_error("block address out of bounds");
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
block_address
|
|
block_manager<BlockSize>::get_nr_blocks() const
|
|
{
|
|
return io_->get_nr_blocks();
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
void
|
|
block_manager<BlockSize>::write_block(typename block::ptr b) const
|
|
{
|
|
b->flush();
|
|
}
|
|
|
|
template <uint32_t BlockSize>
|
|
void
|
|
block_manager<BlockSize>::flush() const
|
|
{
|
|
cache_.iterate_unheld(
|
|
boost::bind(&block_manager<BlockSize>::write_block, this, _1));
|
|
}
|
|
|
|
//----------------------------------------------------------------
|