JYCache/s3fs/fdcache_page.cpp

1036 lines
36 KiB
C++

/*
* s3fs - FUSE-based file system backed by Amazon S3
*
* Copyright(C) 2007 Takeshi Nakatani <ggtakec.com>
*
* This program 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 2
* of the License, or (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <cstdio>
#include <cerrno>
#include <memory>
#include <unistd.h>
#include <sstream>
#include <sys/stat.h>
#include "common.h"
#include "s3fs_logger.h"
#include "fdcache_page.h"
#include "fdcache_stat.h"
#include "string_util.h"
//------------------------------------------------
// Symbols
//------------------------------------------------
static constexpr int CHECK_CACHEFILE_PART_SIZE = 1024 * 16; // Buffer size in PageList::CheckZeroAreaInFile()
//------------------------------------------------
// fdpage_list_t utility
//------------------------------------------------
// Inline function for repeated processing
inline void raw_add_compress_fdpage_list(fdpage_list_t& pagelist, const fdpage& orgpage, bool ignore_load, bool ignore_modify, bool default_load, bool default_modify)
{
if(0 < orgpage.bytes){
// [NOTE]
// The page variable is subject to change here.
//
fdpage page = orgpage;
if(ignore_load){
page.loaded = default_load;
}
if(ignore_modify){
page.modified = default_modify;
}
pagelist.push_back(page);
}
}
// Compress the page list
//
// ignore_load: Ignore the flag of loaded member and compress
// ignore_modify: Ignore the flag of modified member and compress
// default_load: loaded flag value in the list after compression when ignore_load=true
// default_modify: modified flag value in the list after compression when default_modify=true
//
// NOTE: ignore_modify and ignore_load cannot both be true.
// Zero size pages will be deleted. However, if the page information is the only one,
// it will be left behind. This is what you need to do to create a new empty file.
//
static void raw_compress_fdpage_list(const fdpage_list_t& pages, fdpage_list_t& compressed_pages, bool ignore_load, bool ignore_modify, bool default_load, bool default_modify)
{
compressed_pages.clear();
fdpage* lastpage = nullptr;
fdpage_list_t::iterator add_iter;
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(0 == iter->bytes){
continue;
}
if(!lastpage){
// First item
raw_add_compress_fdpage_list(compressed_pages, (*iter), ignore_load, ignore_modify, default_load, default_modify);
lastpage = &(compressed_pages.back());
}else{
// check page continuity
if(lastpage->next() != iter->offset){
// Non-consecutive with last page, so add a page filled with default values
if( (!ignore_load && (lastpage->loaded != false)) ||
(!ignore_modify && (lastpage->modified != false)) )
{
// add new page
fdpage tmppage(lastpage->next(), (iter->offset - lastpage->next()), false, false);
raw_add_compress_fdpage_list(compressed_pages, tmppage, ignore_load, ignore_modify, default_load, default_modify);
add_iter = compressed_pages.end();
--add_iter;
lastpage = &(*add_iter);
}else{
// Expand last area
lastpage->bytes = iter->offset - lastpage->offset;
}
}
// add current page
if( (!ignore_load && (lastpage->loaded != iter->loaded )) ||
(!ignore_modify && (lastpage->modified != iter->modified)) )
{
// Add new page
raw_add_compress_fdpage_list(compressed_pages, (*iter), ignore_load, ignore_modify, default_load, default_modify);
add_iter = compressed_pages.end();
--add_iter;
lastpage = &(*add_iter);
}else{
// Expand last area
lastpage->bytes += iter->bytes;
}
}
}
}
static void compress_fdpage_list_ignore_modify(const fdpage_list_t& pages, fdpage_list_t& compressed_pages, bool default_modify)
{
raw_compress_fdpage_list(pages, compressed_pages, /* ignore_load= */ false, /* ignore_modify= */ true, /* default_load= */false, /* default_modify= */default_modify);
}
static void compress_fdpage_list_ignore_load(const fdpage_list_t& pages, fdpage_list_t& compressed_pages, bool default_load)
{
raw_compress_fdpage_list(pages, compressed_pages, /* ignore_load= */ true, /* ignore_modify= */ false, /* default_load= */default_load, /* default_modify= */false);
}
static void compress_fdpage_list(const fdpage_list_t& pages, fdpage_list_t& compressed_pages)
{
raw_compress_fdpage_list(pages, compressed_pages, /* ignore_load= */ false, /* ignore_modify= */ false, /* default_load= */false, /* default_modify= */false);
}
static fdpage_list_t parse_partsize_fdpage_list(const fdpage_list_t& pages, off_t max_partsize)
{
fdpage_list_t parsed_pages;
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->modified){
// modified page
fdpage tmppage = *iter;
for(off_t start = iter->offset, rest_bytes = iter->bytes; 0 < rest_bytes; ){
if((max_partsize * 2) < rest_bytes){
// do parse
tmppage.offset = start;
tmppage.bytes = max_partsize;
parsed_pages.push_back(tmppage);
start += max_partsize;
rest_bytes -= max_partsize;
}else{
// Since the number of remaining bytes is less than twice max_partsize,
// one of the divided areas will be smaller than max_partsize.
// Therefore, this area at the end should not be divided.
tmppage.offset = start;
tmppage.bytes = rest_bytes;
parsed_pages.push_back(tmppage);
start += rest_bytes;
rest_bytes = 0;
}
}
}else{
// not modified page is not parsed
parsed_pages.push_back(*iter);
}
}
return parsed_pages;
}
//------------------------------------------------
// PageList class methods
//------------------------------------------------
//
// Examine and return the status of each block in the file.
//
// Assuming the file is a sparse file, check the HOLE and DATA areas
// and return it in fdpage_list_t. The loaded flag of each fdpage is
// set to false for HOLE blocks and true for DATA blocks.
//
bool PageList::GetSparseFilePages(int fd, size_t file_size, fdpage_list_t& sparse_list)
{
// [NOTE]
// Express the status of the cache file using fdpage_list_t.
// There is a hole in the cache file(sparse file), and the
// state of this hole is expressed by the "loaded" member of
// struct fdpage. (the "modified" member is not used)
//
if(0 == file_size){
// file is empty
return true;
}
bool is_hole = false;
off_t hole_pos = lseek(fd, 0, SEEK_HOLE);
off_t data_pos = lseek(fd, 0, SEEK_DATA);
if(-1 == hole_pos && -1 == data_pos){
S3FS_PRN_ERR("Could not find the first position both HOLE and DATA in the file(physical_fd=%d).", fd);
return false;
}else if(-1 == hole_pos){
is_hole = false;
}else if(-1 == data_pos){
is_hole = true;
}else if(hole_pos < data_pos){
is_hole = true;
}else{
is_hole = false;
}
for(off_t cur_pos = 0, next_pos = 0; 0 <= cur_pos; cur_pos = next_pos, is_hole = !is_hole){
fdpage page;
page.offset = cur_pos;
page.loaded = !is_hole;
page.modified = false;
next_pos = lseek(fd, cur_pos, (is_hole ? SEEK_DATA : SEEK_HOLE));
if(-1 == next_pos){
page.bytes = static_cast<off_t>(file_size - cur_pos);
}else{
page.bytes = next_pos - cur_pos;
}
sparse_list.push_back(page);
}
return true;
}
//
// Confirm that the specified area is ZERO
//
bool PageList::CheckZeroAreaInFile(int fd, off_t start, size_t bytes)
{
std::unique_ptr<char[]> readbuff(new char[CHECK_CACHEFILE_PART_SIZE]);
for(size_t comp_bytes = 0, check_bytes = 0; comp_bytes < bytes; comp_bytes += check_bytes){
if(CHECK_CACHEFILE_PART_SIZE < (bytes - comp_bytes)){
check_bytes = CHECK_CACHEFILE_PART_SIZE;
}else{
check_bytes = bytes - comp_bytes;
}
bool found_bad_data = false;
ssize_t read_bytes;
if(-1 == (read_bytes = pread(fd, readbuff.get(), check_bytes, (start + comp_bytes)))){
S3FS_PRN_ERR("Something error is occurred in reading %zu bytes at %lld from file(physical_fd=%d).", check_bytes, static_cast<long long int>(start + comp_bytes), fd);
found_bad_data = true;
}else{
check_bytes = static_cast<size_t>(read_bytes);
for(size_t tmppos = 0; tmppos < check_bytes; ++tmppos){
if('\0' != readbuff[tmppos]){
// found not ZERO data.
found_bad_data = true;
break;
}
}
}
if(found_bad_data){
return false;
}
}
return true;
}
//
// Checks that the specified area matches the state of the sparse file.
//
// [Parameters]
// checkpage: This is one state of the cache file, it is loaded from the stats file.
// sparse_list: This is a list of the results of directly checking the cache file status(HOLE/DATA).
// In the HOLE area, the "loaded" flag of fdpage is false. The DATA area has it set to true.
// fd: opened file discriptor to target cache file.
//
bool PageList::CheckAreaInSparseFile(const struct fdpage& checkpage, const fdpage_list_t& sparse_list, int fd, fdpage_list_t& err_area_list, fdpage_list_t& warn_area_list)
{
// Check the block status of a part(Check Area: checkpage) of the target file.
// The elements of sparse_list have 5 patterns that overlap this block area.
//
// File |<---...--------------------------------------...--->|
// Check Area (offset)<-------------------->(offset + bytes - 1)
// Area case(0) <------->
// Area case(1) <------->
// Area case(2) <-------->
// Area case(3) <---------->
// Area case(4) <----------->
// Area case(5) <----------------------------->
//
bool result = true;
for(fdpage_list_t::const_iterator iter = sparse_list.begin(); iter != sparse_list.end(); ++iter){
off_t check_start = 0;
off_t check_bytes = 0;
if((iter->offset + iter->bytes) <= checkpage.offset){
// case 0
continue; // next
}else if((checkpage.offset + checkpage.bytes) <= iter->offset){
// case 1
break; // finish
}else if(iter->offset < checkpage.offset && (iter->offset + iter->bytes) < (checkpage.offset + checkpage.bytes)){
// case 2
check_start = checkpage.offset;
check_bytes = iter->bytes - (checkpage.offset - iter->offset);
}else if((checkpage.offset + checkpage.bytes) < (iter->offset + iter->bytes)){ // here, already "iter->offset < (checkpage.offset + checkpage.bytes)" is true.
// case 3
check_start = iter->offset;
check_bytes = checkpage.bytes - (iter->offset - checkpage.offset);
}else if(checkpage.offset < iter->offset && (iter->offset + iter->bytes) < (checkpage.offset + checkpage.bytes)){
// case 4
check_start = iter->offset;
check_bytes = iter->bytes;
}else{ // (iter->offset <= checkpage.offset && (checkpage.offset + checkpage.bytes) <= (iter->offset + iter->bytes))
// case 5
check_start = checkpage.offset;
check_bytes = checkpage.bytes;
}
// check target area type
if(checkpage.loaded || checkpage.modified){
// target area must be not HOLE(DATA) area.
if(!iter->loaded){
// Found bad area, it is HOLE area.
fdpage page(check_start, check_bytes, false, false);
err_area_list.push_back(page);
result = false;
}
}else{
// target area should be HOLE area.(If it is not a block boundary, it may be a DATA area.)
if(iter->loaded){
// need to check this area's each data, it should be ZERO.
if(!PageList::CheckZeroAreaInFile(fd, check_start, static_cast<size_t>(check_bytes))){
// Discovered an area that has un-initial status data but it probably does not effect bad.
fdpage page(check_start, check_bytes, true, false);
warn_area_list.push_back(page);
result = false;
}
}
}
}
return result;
}
//------------------------------------------------
// PageList methods
//------------------------------------------------
void PageList::FreeList(fdpage_list_t& list)
{
list.clear();
}
PageList::PageList(off_t size, bool is_loaded, bool is_modified, bool shrinked) : is_shrink(shrinked)
{
Init(size, is_loaded, is_modified);
}
PageList::~PageList()
{
Clear();
}
void PageList::Clear()
{
PageList::FreeList(pages);
is_shrink = false;
}
bool PageList::Init(off_t size, bool is_loaded, bool is_modified)
{
Clear();
if(0 <= size){
fdpage page(0, size, is_loaded, is_modified);
pages.push_back(page);
}
return true;
}
off_t PageList::Size() const
{
if(pages.empty()){
return 0;
}
fdpage_list_t::const_reverse_iterator riter = pages.rbegin();
return riter->next();
}
bool PageList::Compress()
{
fdpage* lastpage = nullptr;
for(fdpage_list_t::iterator iter = pages.begin(); iter != pages.end(); ){
if(!lastpage){
// First item
lastpage = &(*iter);
++iter;
}else{
// check page continuity
if(lastpage->next() != iter->offset){
// Non-consecutive with last page, so add a page filled with default values
if(lastpage->loaded || lastpage->modified){
// insert new page before current pos
fdpage tmppage(lastpage->next(), (iter->offset - lastpage->next()), false, false);
iter = pages.insert(iter, tmppage);
lastpage = &(*iter);
++iter;
}else{
// Expand last area
lastpage->bytes = iter->offset - lastpage->offset;
}
}
// check current page
if(lastpage->loaded == iter->loaded && lastpage->modified == iter->modified){
// Expand last area and remove current pos
lastpage->bytes += iter->bytes;
iter = pages.erase(iter);
}else{
lastpage = &(*iter);
++iter;
}
}
}
return true;
}
bool PageList::Parse(off_t new_pos)
{
for(fdpage_list_t::iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(new_pos == iter->offset){
// nothing to do
return true;
}else if(iter->offset < new_pos && new_pos < iter->next()){
fdpage page(iter->offset, new_pos - iter->offset, iter->loaded, iter->modified);
iter->bytes -= (new_pos - iter->offset);
iter->offset = new_pos;
pages.insert(iter, page);
return true;
}
}
return false;
}
bool PageList::Resize(off_t size, bool is_loaded, bool is_modified)
{
off_t total = Size();
if(0 == total){
// [NOTE]
// The is_shrink flag remains unchanged in this function.
//
bool backup_is_shrink = is_shrink;
Init(size, is_loaded, is_modified);
is_shrink = backup_is_shrink;
}else if(total < size){
// add new area
fdpage page(total, (size - total), is_loaded, is_modified);
pages.push_back(page);
}else if(size < total){
// cut area
for(fdpage_list_t::iterator iter = pages.begin(); iter != pages.end(); ){
if(iter->next() <= size){
++iter;
}else{
if(size <= iter->offset){
iter = pages.erase(iter);
}else{
iter->bytes = size - iter->offset;
}
}
}
if(is_modified){
is_shrink = true;
}
}else{ // total == size
// nothing to do
}
// compress area
return Compress();
}
bool PageList::IsPageLoaded(off_t start, off_t size) const
{
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->end() < start){
continue;
}
if(!iter->loaded){
return false;
}
if(0 != size && start + size <= iter->next()){
break;
}
}
return true;
}
bool PageList::SetPageLoadedStatus(off_t start, off_t size, PageList::page_status pstatus, bool is_compress)
{
off_t now_size = Size();
bool is_loaded = (page_status::LOAD_MODIFIED == pstatus || page_status::LOADED == pstatus);
bool is_modified = (page_status::LOAD_MODIFIED == pstatus || page_status::MODIFIED == pstatus);
if(now_size <= start){
if(now_size < start){
// add
Resize(start, false, is_modified); // set modified flag from now end pos to specified start pos.
}
Resize(start + size, is_loaded, is_modified);
}else if(now_size <= start + size){
// cut
Resize(start, false, false); // not changed loaded/modified flags in existing area.
// add
Resize(start + size, is_loaded, is_modified);
}else{
// start-size are inner pages area
// parse "start", and "start + size" position
Parse(start);
Parse(start + size);
// set loaded flag
for(fdpage_list_t::iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->end() < start){
continue;
}else if(start + size <= iter->offset){
break;
}else{
iter->loaded = is_loaded;
iter->modified = is_modified;
}
}
}
// compress area
return (is_compress ? Compress() : true);
}
bool PageList::FindUnloadedPage(off_t start, off_t& resstart, off_t& ressize) const
{
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(start <= iter->end()){
if(!iter->loaded && !iter->modified){ // Do not load unloaded and modified areas
resstart = iter->offset;
ressize = iter->bytes;
return true;
}
}
}
return false;
}
// [NOTE]
// Accumulates the range of unload that is smaller than the Limit size.
// If you want to integrate all unload ranges, set the limit size to 0.
//
off_t PageList::GetTotalUnloadedPageSize(off_t start, off_t size, off_t limit_size) const
{
// If size is 0, it means loading to end.
if(0 == size){
if(start < Size()){
size = Size() - start;
}
}
off_t next = start + size;
off_t restsize = 0;
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->next() <= start){
continue;
}
if(next <= iter->offset){
break;
}
if(iter->loaded || iter->modified){
continue;
}
off_t tmpsize;
if(iter->offset <= start){
if(iter->next() <= next){
tmpsize = (iter->next() - start);
}else{
tmpsize = next - start; // = size
}
}else{
if(iter->next() <= next){
tmpsize = iter->next() - iter->offset; // = iter->bytes
}else{
tmpsize = next - iter->offset;
}
}
if(0 == limit_size || tmpsize < limit_size){
restsize += tmpsize;
}
}
return restsize;
}
size_t PageList::GetUnloadedPages(fdpage_list_t& unloaded_list, off_t start, off_t size) const
{
// If size is 0, it means loading to end.
if(0 == size){
if(start < Size()){
size = Size() - start;
}
}
off_t next = start + size;
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->next() <= start){
continue;
}
if(next <= iter->offset){
break;
}
if(iter->loaded || iter->modified){
continue; // already loaded or modified
}
// page area
off_t page_start = std::max(iter->offset, start);
off_t page_next = std::min(iter->next(), next);
off_t page_size = page_next - page_start;
// add list
fdpage_list_t::reverse_iterator riter = unloaded_list.rbegin();
if(riter != unloaded_list.rend() && riter->next() == page_start){
// merge to before page
riter->bytes += page_size;
}else{
fdpage page(page_start, page_size, false, false);
unloaded_list.push_back(page);
}
}
return unloaded_list.size();
}
// [NOTE]
// This method is called in advance when mixing POST and COPY in multi-part upload.
// The minimum size of each part must be 5 MB, and the data area below this must be
// downloaded from S3.
// This method checks the current PageList status and returns the area that needs
// to be downloaded so that each part is at least 5 MB.
//
bool PageList::GetPageListsForMultipartUpload(fdpage_list_t& dlpages, fdpage_list_t& mixuppages, off_t max_partsize)
{
// compress before this processing
Compress(); // always true
// make a list by modified flag
fdpage_list_t modified_pages;
fdpage_list_t download_pages; // A non-contiguous page list showing the areas that need to be downloaded
fdpage_list_t mixupload_pages; // A continuous page list showing only modified flags for mixupload
compress_fdpage_list_ignore_load(pages, modified_pages, false);
fdpage prev_page;
for(fdpage_list_t::const_iterator iter = modified_pages.begin(); iter != modified_pages.end(); ++iter){
if(iter->modified){
// current is modified area
if(!prev_page.modified){
// previous is not modified area
if(prev_page.bytes < MIN_MULTIPART_SIZE){
// previous(not modified) area is too small for one multipart size,
// then all of previous area is needed to download.
download_pages.push_back(prev_page);
// previous(not modified) area is set upload area.
prev_page.modified = true;
mixupload_pages.push_back(prev_page);
}else{
// previous(not modified) area is set copy area.
prev_page.modified = false;
mixupload_pages.push_back(prev_page);
}
// set current to previous
prev_page = *iter;
}else{
// previous is modified area, too
prev_page.bytes += iter->bytes;
}
}else{
// current is not modified area
if(!prev_page.modified){
// previous is not modified area, too
prev_page.bytes += iter->bytes;
}else{
// previous is modified area
if(prev_page.bytes < MIN_MULTIPART_SIZE){
// previous(modified) area is too small for one multipart size,
// then part or all of current area is needed to download.
off_t missing_bytes = MIN_MULTIPART_SIZE - prev_page.bytes;
if((missing_bytes + MIN_MULTIPART_SIZE) < iter-> bytes){
// The current size is larger than the missing size, and the remainder
// after deducting the missing size is larger than the minimum size.
fdpage missing_page(iter->offset, missing_bytes, false, false);
download_pages.push_back(missing_page);
// previous(not modified) area is set upload area.
prev_page.bytes = MIN_MULTIPART_SIZE;
mixupload_pages.push_back(prev_page);
// set current to previous
prev_page = *iter;
prev_page.offset += missing_bytes;
prev_page.bytes -= missing_bytes;
}else{
// The current size is less than the missing size, or the remaining
// size less the missing size is less than the minimum size.
download_pages.push_back(*iter);
// add current to previous
prev_page.bytes += iter->bytes;
}
}else{
// previous(modified) area is enough size for one multipart size.
mixupload_pages.push_back(prev_page);
// set current to previous
prev_page = *iter;
}
}
}
}
// last area
if(0 < prev_page.bytes){
mixupload_pages.push_back(prev_page);
}
// compress
compress_fdpage_list_ignore_modify(download_pages, dlpages, false);
compress_fdpage_list_ignore_load(mixupload_pages, mixuppages, false);
// parse by max pagesize
dlpages = parse_partsize_fdpage_list(dlpages, max_partsize);
mixuppages = parse_partsize_fdpage_list(mixuppages, max_partsize);
return true;
}
bool PageList::GetNoDataPageLists(fdpage_list_t& nodata_pages, off_t start, size_t size)
{
// compress before this processing
Compress(); // always true
// extract areas without data
fdpage_list_t tmp_pagelist;
off_t stop_pos = (0L == size ? -1 : (start + size));
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if((iter->offset + iter->bytes) < start){
continue;
}
if(-1 != stop_pos && stop_pos <= iter->offset){
break;
}
if(iter->modified){
continue;
}
fdpage tmppage;
tmppage.offset = std::max(iter->offset, start);
tmppage.bytes = (-1 == stop_pos ? iter->bytes : std::min(iter->bytes, (stop_pos - tmppage.offset)));
tmppage.loaded = iter->loaded;
tmppage.modified = iter->modified;
tmp_pagelist.push_back(tmppage);
}
if(tmp_pagelist.empty()){
nodata_pages.clear();
}else{
// compress
compress_fdpage_list(tmp_pagelist, nodata_pages);
}
return true;
}
off_t PageList::BytesModified() const
{
off_t total = 0;
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->modified){
total += iter->bytes;
}
}
return total;
}
bool PageList::IsModified() const
{
if(is_shrink){
return true;
}
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->modified){
return true;
}
}
return false;
}
bool PageList::ClearAllModified()
{
is_shrink = false;
for(fdpage_list_t::iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(iter->modified){
iter->modified = false;
}
}
return Compress();
}
bool PageList::Serialize(CacheFileStat& file, bool is_output, ino_t inode)
{
if(!file.Open()){
return false;
}
if(is_output){
//
// put to file
//
std::ostringstream ssall;
ssall << inode << ":" << Size();
for(fdpage_list_t::iterator iter = pages.begin(); iter != pages.end(); ++iter){
ssall << "\n" << iter->offset << ":" << iter->bytes << ":" << (iter->loaded ? "1" : "0") << ":" << (iter->modified ? "1" : "0");
}
if(-1 == ftruncate(file.GetFd(), 0)){
S3FS_PRN_ERR("failed to truncate file(to 0) for stats(%d)", errno);
return false;
}
std::string strall = ssall.str();
if(0 >= pwrite(file.GetFd(), strall.c_str(), strall.length(), 0)){
S3FS_PRN_ERR("failed to write stats(%d)", errno);
return false;
}
}else{
//
// loading from file
//
struct stat st;
memset(&st, 0, sizeof(struct stat));
if(-1 == fstat(file.GetFd(), &st)){
S3FS_PRN_ERR("fstat is failed. errno(%d)", errno);
return false;
}
if(0 >= st.st_size){
// nothing
Init(0, false, false);
return true;
}
std::unique_ptr<char[]> ptmp(new char[st.st_size + 1]);
ssize_t result;
// read from file
if(0 >= (result = pread(file.GetFd(), ptmp.get(), st.st_size, 0))){
S3FS_PRN_ERR("failed to read stats(%d)", errno);
return false;
}
ptmp[result] = '\0';
std::string oneline;
std::istringstream ssall(ptmp.get());
// loaded
Clear();
// load head line(for size and inode)
off_t total;
ino_t cache_inode; // if this value is 0, it means old format.
if(!getline(ssall, oneline, '\n')){
S3FS_PRN_ERR("failed to parse stats.");
return false;
}else{
std::istringstream sshead(oneline);
std::string strhead1;
std::string strhead2;
// get first part in head line.
if(!getline(sshead, strhead1, ':')){
S3FS_PRN_ERR("failed to parse stats.");
return false;
}
// get second part in head line.
if(!getline(sshead, strhead2, ':')){
// old head format is "<size>\n"
total = cvt_strtoofft(strhead1.c_str(), /* base= */10);
cache_inode = 0;
}else{
// current head format is "<inode>:<size>\n"
total = cvt_strtoofft(strhead2.c_str(), /* base= */10);
cache_inode = static_cast<ino_t>(cvt_strtoofft(strhead1.c_str(), /* base= */10));
if(0 == cache_inode){
S3FS_PRN_ERR("wrong inode number in parsed cache stats.");
return false;
}
}
}
// check inode number
if(0 != cache_inode && cache_inode != inode){
S3FS_PRN_ERR("differ inode and inode number in parsed cache stats.");
return false;
}
// load each part
bool is_err = false;
while(getline(ssall, oneline, '\n')){
std::string part;
std::istringstream ssparts(oneline);
// offset
if(!getline(ssparts, part, ':')){
is_err = true;
break;
}
off_t offset = cvt_strtoofft(part.c_str(), /* base= */10);
// size
if(!getline(ssparts, part, ':')){
is_err = true;
break;
}
off_t size = cvt_strtoofft(part.c_str(), /* base= */10);
// loaded
if(!getline(ssparts, part, ':')){
is_err = true;
break;
}
bool is_loaded = (1 == cvt_strtoofft(part.c_str(), /* base= */10) ? true : false);
bool is_modified;
if(!getline(ssparts, part, ':')){
is_modified = false; // old version does not have this part.
}else{
is_modified = (1 == cvt_strtoofft(part.c_str(), /* base= */10) ? true : false);
}
// add new area
PageList::page_status pstatus = PageList::page_status::NOT_LOAD_MODIFIED;
if(is_loaded){
if(is_modified){
pstatus = PageList::page_status::LOAD_MODIFIED;
}else{
pstatus = PageList::page_status::LOADED;
}
}else{
if(is_modified){
pstatus = PageList::page_status::MODIFIED;
}
}
SetPageLoadedStatus(offset, size, pstatus);
}
if(is_err){
S3FS_PRN_ERR("failed to parse stats.");
Clear();
return false;
}
// check size
if(total != Size()){
S3FS_PRN_ERR("different size(%lld - %lld).", static_cast<long long int>(total), static_cast<long long int>(Size()));
Clear();
return false;
}
}
return true;
}
void PageList::Dump() const
{
int cnt = 0;
S3FS_PRN_DBG("pages (shrinked=%s) = {", (is_shrink ? "yes" : "no"));
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter, ++cnt){
S3FS_PRN_DBG(" [%08d] -> {%014lld - %014lld : %s / %s}", cnt, static_cast<long long int>(iter->offset), static_cast<long long int>(iter->bytes), iter->loaded ? "loaded" : "unloaded", iter->modified ? "modified" : "not modified");
}
S3FS_PRN_DBG("}");
}
//
// Compare the fdpage_list_t pages of the object with the state of the file.
//
// The loaded=true or modified=true area of pages must be a DATA block
// (not a HOLE block) in the file.
// The other area is a HOLE block in the file or is a DATA block(but the
// data of the target area in that block should be ZERO).
// If it is a bad area in the previous case, it will be reported as an error.
// If the latter case does not match, it will be reported as a warning.
//
bool PageList::CompareSparseFile(int fd, size_t file_size, fdpage_list_t& err_area_list, fdpage_list_t& warn_area_list)
{
err_area_list.clear();
warn_area_list.clear();
// First, list the block disk allocation area of the cache file.
// The cache file has holes(sparse file) and no disk block areas
// are assigned to any holes.
fdpage_list_t sparse_list;
if(!PageList::GetSparseFilePages(fd, file_size, sparse_list)){
S3FS_PRN_ERR("Something error is occurred in parsing hole/data of the cache file(physical_fd=%d).", fd);
fdpage page(0, static_cast<off_t>(file_size), false, false);
err_area_list.push_back(page);
return false;
}
if(sparse_list.empty() && pages.empty()){
// both file and stats information are empty, it means cache file size is ZERO.
return true;
}
// Compare each pages and sparse_list
bool result = true;
for(fdpage_list_t::const_iterator iter = pages.begin(); iter != pages.end(); ++iter){
if(!PageList::CheckAreaInSparseFile(*iter, sparse_list, fd, err_area_list, warn_area_list)){
result = false;
}
}
return result;
}
/*
* Local variables:
* tab-width: 4
* c-basic-offset: 4
* End:
* vim600: expandtab sw=4 ts=4 fdm=marker
* vim<600: expandtab sw=4 ts=4
*/