minio/cmd/posix.go
Anis Elleuch 4098025c11 Remove XL multipart tmp files when the latter is canceled (#3214)
XL multipart fails to remove tmp files when an error occurs during upload, this case covers the scenario where an upload is canceled manually by the client in the middle of job.
2016-11-21 16:34:57 -08:00

955 lines
22 KiB
Go

/*
* Minio Cloud Storage, (C) 2016 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cmd
import (
"bytes"
"io"
"io/ioutil"
"os"
slashpath "path"
"path/filepath"
"runtime"
"strings"
"sync"
"sync/atomic"
"syscall"
"github.com/minio/minio/pkg/disk"
)
const (
fsMinFreeSpace = 1024 * 1024 * 1024 // Min 1GiB free space.
fsMinFreeInodes = 10000 // Min 10000.
maxAllowedIOError = 5
)
// posix - implements StorageAPI interface.
type posix struct {
ioErrCount int32 // ref: https://golang.org/pkg/sync/atomic/#pkg-note-BUG
diskPath string
minFreeSpace int64
minFreeInodes int64
pool sync.Pool
}
// checkPathLength - returns error if given path name length more than 255
func checkPathLength(pathName string) error {
// Apple OS X path length is limited to 1016
if runtime.GOOS == "darwin" && len(pathName) > 1016 {
return errFileNameTooLong
}
// Convert any '\' to '/'.
pathName = filepath.ToSlash(pathName)
// Check each path segment length is > 255
for len(pathName) > 0 && pathName != "." && pathName != "/" {
dir, file := slashpath.Dir(pathName), slashpath.Base(pathName)
if len(file) > 255 {
return errFileNameTooLong
}
pathName = dir
} // Success.
return nil
}
// isDirEmpty - returns whether given directory is empty or not.
func isDirEmpty(dirname string) bool {
f, err := os.Open(dirname)
if err != nil {
errorIf(func() error {
if !os.IsNotExist(err) {
return err
}
return nil
}(), "Unable to access directory.")
return false
}
defer f.Close()
// List one entry.
_, err = f.Readdirnames(1)
if err != io.EOF {
errorIf(func() error {
if !os.IsNotExist(err) {
return err
}
return nil
}(), "Unable to list directory.")
return false
}
// Returns true if we have reached EOF, directory is indeed empty.
return true
}
// Initialize a new storage disk.
func newPosix(path string) (StorageAPI, error) {
if path == "" {
return nil, errInvalidArgument
}
// Disallow relative paths, figure out absolute paths.
diskPath, err := filepath.Abs(path)
if err != nil {
return nil, err
}
fs := &posix{
diskPath: diskPath,
minFreeSpace: fsMinFreeSpace,
minFreeInodes: fsMinFreeInodes,
// 1MiB buffer pool for posix internal operations.
pool: sync.Pool{
New: func() interface{} {
b := make([]byte, readSizeV1)
return &b
},
},
}
fi, err := os.Stat(preparePath(diskPath))
if err == nil {
if !fi.IsDir() {
return nil, syscall.ENOTDIR
}
}
if os.IsNotExist(err) {
// Disk not found create it.
err = os.MkdirAll(preparePath(diskPath), 0777)
if err != nil {
return nil, err
}
}
if err = fs.checkDiskFree(); err != nil {
return nil, err
}
return fs, nil
}
// getDiskInfo returns given disk information.
func getDiskInfo(diskPath string) (di disk.Info, err error) {
if err = checkPathLength(diskPath); err == nil {
di, err = disk.GetInfo(diskPath)
}
if os.IsNotExist(err) {
err = errDiskNotFound
}
return di, err
}
// checkDiskFree verifies if disk path has sufficient minimum free disk space and files.
func (s *posix) checkDiskFree() (err error) {
// We don't validate disk space or inode utilization on windows.
// Each windows calls to 'GetVolumeInformationW' takes around 3-5seconds.
if runtime.GOOS == "windows" {
return nil
}
var di disk.Info
di, err = getDiskInfo(preparePath(s.diskPath))
if err != nil {
return err
}
// Remove 5% from free space for cumulative disk space used for journalling, inodes etc.
availableDiskSpace := float64(di.Free) * 0.95
if int64(availableDiskSpace) <= s.minFreeSpace {
return errDiskFull
}
// Some filesystems do not implement a way to provide total inodes available, instead inodes
// are allocated based on available disk space. For example CephFS, StoreNext CVFS, AzureFile driver.
// Allow for the available disk to be separately validate and we will validate inodes only if
// total inodes are provided by the underlying filesystem.
if di.Files != 0 {
availableFiles := int64(di.Ffree)
if availableFiles <= s.minFreeInodes {
return errDiskFull
}
}
// Success.
return nil
}
// Implements stringer compatible interface.
func (s *posix) String() string {
return s.diskPath
}
// DiskInfo provides current information about disk space usage,
// total free inodes and underlying filesystem.
func (s *posix) DiskInfo() (info disk.Info, err error) {
return getDiskInfo(preparePath(s.diskPath))
}
// getVolDir - will convert incoming volume names to
// corresponding valid volume names on the backend in a platform
// compatible way for all operating systems. If volume is not found
// an error is generated.
func (s *posix) getVolDir(volume string) (string, error) {
if !isValidVolname(volume) {
return "", errInvalidArgument
}
volumeDir := pathJoin(s.diskPath, volume)
return volumeDir, nil
}
// checkDiskFound - validates if disk is available,
// returns errDiskNotFound if not found.
func (s *posix) checkDiskFound() (err error) {
_, err = os.Stat(preparePath(s.diskPath))
if err != nil {
if os.IsNotExist(err) {
return errDiskNotFound
} else if isSysErrTooLong(err) {
return errFileNameTooLong
}
}
return err
}
// Make a volume entry.
func (s *posix) MakeVol(volume string) (err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return err
}
volumeDir, err := s.getVolDir(volume)
if err != nil {
return err
}
// Make a volume entry, with mode 0777 mkdir honors system umask.
err = os.Mkdir(preparePath(volumeDir), 0777)
if err != nil {
if os.IsExist(err) {
return errVolumeExists
} else if os.IsPermission(err) {
return errDiskAccessDenied
}
return err
}
// Success
return nil
}
// ListVols - list volumes.
func (s *posix) ListVols() (volsInfo []VolInfo, err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return nil, errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return nil, err
}
volsInfo, err = listVols(preparePath(s.diskPath))
if err != nil {
return nil, err
}
for i, vol := range volsInfo {
volInfo := VolInfo{
Name: vol.Name,
Created: vol.Created,
}
volsInfo[i] = volInfo
}
return volsInfo, nil
}
// List all the volumes from diskPath.
func listVols(dirPath string) ([]VolInfo, error) {
if err := checkPathLength(dirPath); err != nil {
return nil, err
}
entries, err := readDir(dirPath)
if err != nil {
return nil, errDiskNotFound
}
var volsInfo []VolInfo
for _, entry := range entries {
if !strings.HasSuffix(entry, slashSeparator) || !isValidVolname(slashpath.Clean(entry)) {
// Skip if entry is neither a directory not a valid volume name.
continue
}
var fi os.FileInfo
fi, err = os.Stat(preparePath(pathJoin(dirPath, entry)))
if err != nil {
// If the file does not exist, skip the entry.
if os.IsNotExist(err) {
continue
}
return nil, err
}
volsInfo = append(volsInfo, VolInfo{
Name: fi.Name(),
// As os.Stat() doesn't carry other than ModTime(), use
// ModTime() as CreatedTime.
Created: fi.ModTime(),
})
}
return volsInfo, nil
}
// StatVol - get volume info.
func (s *posix) StatVol(volume string) (volInfo VolInfo, err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return VolInfo{}, errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return VolInfo{}, err
}
// Verify if volume is valid and it exists.
volumeDir, err := s.getVolDir(volume)
if err != nil {
return VolInfo{}, err
}
// Stat a volume entry.
var st os.FileInfo
st, err = os.Stat(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return VolInfo{}, errVolumeNotFound
}
return VolInfo{}, err
}
// As os.Stat() doesn't carry other than ModTime(), use ModTime()
// as CreatedTime.
createdTime := st.ModTime()
return VolInfo{
Name: volume,
Created: createdTime,
}, nil
}
// DeleteVol - delete a volume.
func (s *posix) DeleteVol(volume string) (err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return err
}
// Verify if volume is valid and it exists.
volumeDir, err := s.getVolDir(volume)
if err != nil {
return err
}
err = os.Remove(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return errVolumeNotFound
} else if isSysErrNotEmpty(err) {
return errVolumeNotEmpty
}
return err
}
return nil
}
// ListDir - return all the entries at the given directory path.
// If an entry is a directory it will be returned with a trailing "/".
func (s *posix) ListDir(volume, dirPath string) (entries []string, err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return nil, errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return nil, err
}
// Verify if volume is valid and it exists.
volumeDir, err := s.getVolDir(volume)
if err != nil {
return nil, err
}
// Stat a volume entry.
_, err = os.Stat(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return nil, errVolumeNotFound
}
return nil, err
}
return readDir(pathJoin(volumeDir, dirPath))
}
// ReadAll reads from r until an error or EOF and returns the data it read.
// A successful call returns err == nil, not err == EOF. Because ReadAll is
// defined to read from src until EOF, it does not treat an EOF from Read
// as an error to be reported.
// This API is meant to be used on files which have small memory footprint, do
// not use this on large files as it would cause server to crash.
func (s *posix) ReadAll(volume, path string) (buf []byte, err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return nil, errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return nil, err
}
volumeDir, err := s.getVolDir(volume)
if err != nil {
return nil, err
}
// Stat a volume entry.
_, err = os.Stat(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return nil, errVolumeNotFound
}
return nil, err
}
// Validate file path length, before reading.
filePath := pathJoin(volumeDir, path)
if err = checkPathLength(preparePath(filePath)); err != nil {
return nil, err
}
// Open the file for reading.
buf, err = ioutil.ReadFile(preparePath(filePath))
if err != nil {
if os.IsNotExist(err) {
return nil, errFileNotFound
} else if os.IsPermission(err) {
return nil, errFileAccessDenied
} else if pathErr, ok := err.(*os.PathError); ok {
switch pathErr.Err {
case syscall.ENOTDIR, syscall.EISDIR:
return nil, errFileNotFound
default:
if isSysErrHandleInvalid(pathErr.Err) {
// This case is special and needs to be handled for windows.
return nil, errFileNotFound
}
}
return nil, pathErr
}
return nil, err
}
return buf, nil
}
// ReadFile reads exactly len(buf) bytes into buf. It returns the
// number of bytes copied. The error is EOF only if no bytes were
// read. On return, n == len(buf) if and only if err == nil. n == 0
// for io.EOF.
// If an EOF happens after reading some but not all the bytes,
// ReadFull returns ErrUnexpectedEOF.
// Additionally ReadFile also starts reading from an offset.
// ReadFile symantics are same as io.ReadFull
func (s *posix) ReadFile(volume string, path string, offset int64, buf []byte) (n int64, err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return 0, errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return 0, err
}
volumeDir, err := s.getVolDir(volume)
if err != nil {
return 0, err
}
// Stat a volume entry.
_, err = os.Stat(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return 0, errVolumeNotFound
}
return 0, err
}
// Validate effective path length before reading.
filePath := pathJoin(volumeDir, path)
if err = checkPathLength(preparePath(filePath)); err != nil {
return 0, err
}
// Open the file for reading.
file, err := os.Open(preparePath(filePath))
if err != nil {
if os.IsNotExist(err) {
return 0, errFileNotFound
} else if os.IsPermission(err) {
return 0, errFileAccessDenied
} else if isSysErrNotDir(err) {
return 0, errFileAccessDenied
}
return 0, err
}
// Close the file descriptor.
defer file.Close()
st, err := file.Stat()
if err != nil {
return 0, err
}
// Verify if its not a regular file, since subsequent Seek is undefined.
if !st.Mode().IsRegular() {
return 0, errIsNotRegular
}
// Seek to requested offset.
_, err = file.Seek(offset, os.SEEK_SET)
if err != nil {
return 0, err
}
// Read full until buffer.
m, err := io.ReadFull(file, buf)
// Success.
return int64(m), err
}
func (s *posix) createFile(volume, path string) (f *os.File, err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return nil, errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return nil, err
}
volumeDir, err := s.getVolDir(volume)
if err != nil {
return nil, err
}
// Stat a volume entry.
_, err = os.Stat(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return nil, errVolumeNotFound
}
return nil, err
}
filePath := pathJoin(volumeDir, path)
if err = checkPathLength(preparePath(filePath)); err != nil {
return nil, err
}
// Verify if the file already exists and is not of regular type.
var st os.FileInfo
if st, err = os.Stat(preparePath(filePath)); err == nil {
if !st.Mode().IsRegular() {
return nil, errIsNotRegular
}
} else {
// Create top level directories if they don't exist.
// with mode 0777 mkdir honors system umask.
if err = mkdirAll(preparePath(slashpath.Dir(filePath)), 0777); err != nil {
// File path cannot be verified since one of the parents is a file.
if isSysErrNotDir(err) {
return nil, errFileAccessDenied
} else if isSysErrPathNotFound(err) {
// Add specific case for windows.
return nil, errFileAccessDenied
}
return nil, err
}
}
w, err := os.OpenFile(preparePath(filePath), os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0666)
if err != nil {
// File path cannot be verified since one of the parents is a file.
if isSysErrNotDir(err) {
return nil, errFileAccessDenied
}
return nil, err
}
return w, nil
}
// PrepareFile - run prior actions before creating a new file for optimization purposes
// Currently we use fallocate when available to avoid disk fragmentation as much as possible
func (s *posix) PrepareFile(volume, path string, fileSize int64) (err error) {
// It doesn't make sense to create a negative-sized file
if fileSize <= 0 {
return errInvalidArgument
}
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return errFaultyDisk
}
// Validate if disk is indeed free.
if err = s.checkDiskFree(); err != nil {
return err
}
// Create file if not found
w, err := s.createFile(volume, path)
if err != nil {
return err
}
// Close upon return.
defer w.Close()
// Allocate needed disk space to append data
e := Fallocate(int(w.Fd()), 0, fileSize)
// Ignore errors when Fallocate is not supported in the current system
if e != nil && !isSysErrNoSys(e) && !isSysErrOpNotSupported(e) {
switch {
case isSysErrNoSpace(e):
err = errDiskFull
case isSysErrIO(e):
err = e
default:
// For errors: EBADF, EINTR, EINVAL, ENODEV, EPERM, ESPIPE and ETXTBSY
// Appending was failed anyway, returns unexpected error
err = errUnexpected
}
return err
}
return nil
}
// AppendFile - append a byte array at path, if file doesn't exist at
// path this call explicitly creates it.
func (s *posix) AppendFile(volume, path string, buf []byte) (err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return errFaultyDisk
}
// Create file if not found
w, err := s.createFile(volume, path)
if err != nil {
return err
}
// Close upon return.
defer w.Close()
bufp := s.pool.Get().(*[]byte)
// Reuse buffer.
defer s.pool.Put(bufp)
// Return io.Copy
_, err = io.CopyBuffer(w, bytes.NewReader(buf), *bufp)
return err
}
// StatFile - get file info.
func (s *posix) StatFile(volume, path string) (file FileInfo, err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return FileInfo{}, errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return FileInfo{}, err
}
volumeDir, err := s.getVolDir(volume)
if err != nil {
return FileInfo{}, err
}
// Stat a volume entry.
_, err = os.Stat(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return FileInfo{}, errVolumeNotFound
}
return FileInfo{}, err
}
filePath := slashpath.Join(volumeDir, path)
if err = checkPathLength(preparePath(filePath)); err != nil {
return FileInfo{}, err
}
st, err := os.Stat(preparePath(filePath))
if err != nil {
// File is really not found.
if os.IsNotExist(err) {
return FileInfo{}, errFileNotFound
}
// File path cannot be verified since one of the parents is a file.
if isSysErrNotDir(err) {
return FileInfo{}, errFileNotFound
}
// Return all errors here.
return FileInfo{}, err
}
// If its a directory its not a regular file.
if st.Mode().IsDir() {
return FileInfo{}, errFileNotFound
}
return FileInfo{
Volume: volume,
Name: path,
ModTime: st.ModTime(),
Size: st.Size(),
Mode: st.Mode(),
}, nil
}
// deleteFile - delete file path if its empty.
func deleteFile(basePath, deletePath string) error {
if basePath == deletePath {
return nil
}
// Verify if the path exists.
pathSt, err := os.Stat(preparePath(deletePath))
if err != nil {
if os.IsNotExist(err) {
return errFileNotFound
} else if os.IsPermission(err) {
return errFileAccessDenied
}
return err
}
if pathSt.IsDir() && !isDirEmpty(deletePath) {
// Verify if directory is empty.
return nil
}
// Attempt to remove path.
if err := os.Remove(preparePath(deletePath)); err != nil {
if os.IsNotExist(err) {
return errFileNotFound
} else if os.IsPermission(err) {
return errFileAccessDenied
}
return err
}
// Recursively go down the next path and delete again.
if err := deleteFile(basePath, slashpath.Dir(deletePath)); err != nil {
return err
}
return nil
}
// DeleteFile - delete a file at path.
func (s *posix) DeleteFile(volume, path string) (err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return err
}
volumeDir, err := s.getVolDir(volume)
if err != nil {
return err
}
// Stat a volume entry.
_, err = os.Stat(preparePath(volumeDir))
if err != nil {
if os.IsNotExist(err) {
return errVolumeNotFound
}
return err
}
// Following code is needed so that we retain "/" suffix if any in
// path argument.
filePath := pathJoin(volumeDir, path)
if err = checkPathLength(preparePath(filePath)); err != nil {
return err
}
// Delete file and delete parent directory as well if its empty.
return deleteFile(volumeDir, filePath)
}
// RenameFile - rename source path to destination path atomically.
func (s *posix) RenameFile(srcVolume, srcPath, dstVolume, dstPath string) (err error) {
defer func() {
if err == syscall.EIO {
atomic.AddInt32(&s.ioErrCount, 1)
}
}()
if s.ioErrCount > maxAllowedIOError {
return errFaultyDisk
}
if err = s.checkDiskFound(); err != nil {
return err
}
srcVolumeDir, err := s.getVolDir(srcVolume)
if err != nil {
return err
}
dstVolumeDir, err := s.getVolDir(dstVolume)
if err != nil {
return err
}
// Stat a volume entry.
_, err = os.Stat(preparePath(srcVolumeDir))
if err != nil {
if os.IsNotExist(err) {
return errVolumeNotFound
}
return err
}
_, err = os.Stat(preparePath(dstVolumeDir))
if err != nil {
if os.IsNotExist(err) {
return errVolumeNotFound
}
}
srcIsDir := strings.HasSuffix(srcPath, slashSeparator)
dstIsDir := strings.HasSuffix(dstPath, slashSeparator)
// Either src and dst have to be directories or files, else return error.
if !(srcIsDir && dstIsDir || !srcIsDir && !dstIsDir) {
return errFileAccessDenied
}
srcFilePath := slashpath.Join(srcVolumeDir, srcPath)
if err = checkPathLength(preparePath(srcFilePath)); err != nil {
return err
}
dstFilePath := slashpath.Join(dstVolumeDir, dstPath)
if err = checkPathLength(preparePath(dstFilePath)); err != nil {
return err
}
if srcIsDir {
// If source is a directory we expect the destination to be non-existent always.
_, err = os.Stat(preparePath(dstFilePath))
if err == nil {
return errFileAccessDenied
}
if !os.IsNotExist(err) {
return err
}
// Destination does not exist, hence proceed with the rename.
}
// Creates all the parent directories, with mode 0777 mkdir honors system umask.
if err = mkdirAll(preparePath(slashpath.Dir(dstFilePath)), 0777); err != nil {
// File path cannot be verified since one of the parents is a file.
if isSysErrNotDir(err) {
return errFileAccessDenied
} else if isSysErrPathNotFound(err) {
// This is a special case should be handled only for
// windows, because windows API does not return "not a
// directory" error message. Handle this specifically here.
return errFileAccessDenied
}
return err
}
// Finally attempt a rename.
err = os.Rename(preparePath(srcFilePath), preparePath(dstFilePath))
if err != nil {
if os.IsNotExist(err) {
return errFileNotFound
}
return err
}
// Remove parent dir of the source file if empty
if parentDir := slashpath.Dir(preparePath(srcFilePath)); isDirEmpty(parentDir) {
deleteFile(srcVolumeDir, parentDir)
}
return nil
}