diff options
Diffstat (limited to 'runsc/fsgofer/fsgofer.go')
-rw-r--r-- | runsc/fsgofer/fsgofer.go | 150 |
1 files changed, 66 insertions, 84 deletions
diff --git a/runsc/fsgofer/fsgofer.go b/runsc/fsgofer/fsgofer.go index 82a46910e..723e118e1 100644 --- a/runsc/fsgofer/fsgofer.go +++ b/runsc/fsgofer/fsgofer.go @@ -48,36 +48,6 @@ const ( openFlags = syscall.O_NOFOLLOW | syscall.O_CLOEXEC ) -type fileType int - -const ( - regular fileType = iota - directory - symlink - socket - unknown -) - -// String implements fmt.Stringer. -func (f fileType) String() string { - switch f { - case regular: - return "regular" - case directory: - return "directory" - case symlink: - return "symlink" - case socket: - return "socket" - } - return "unknown" -} - -// ControlSocketAddr generates an abstract unix socket name for the given id. -func ControlSocketAddr(id string) string { - return fmt.Sprintf("\x00runsc-gofer.%s", id) -} - // Config sets configuration options for each attach point. type Config struct { // ROMount is set to true if this is a readonly mount. @@ -199,8 +169,6 @@ func (a *attachPoint) makeQID(stat syscall.Stat_t) p9.QID { // entire file up when it's opened in write mode, and would perform badly when // multiple files are only being opened for read (esp. startup). type localFile struct { - p9.DefaultWalkGetAttr - // attachPoint is the attachPoint that serves this localFile. attachPoint *attachPoint @@ -220,8 +188,11 @@ type localFile struct { // if localFile isn't opened. mode p9.OpenFlags - // ft is the fileType for this file. - ft fileType + // fileType for this file. It is equivalent to: + // syscall.Stat_t.Mode & syscall.S_IFMT + fileType uint32 + + qid p9.QID // readDirMu protects against concurrent Readdir calls. readDirMu sync.Mutex @@ -308,29 +279,24 @@ func openAnyFile(path string, fn func(mode int) (*fd.FD, error)) (*fd.FD, bool, return nil, false, extractErrno(err) } -func getSupportedFileType(stat syscall.Stat_t, permitSocket bool) (fileType, error) { - var ft fileType +func checkSupportedFileType(stat syscall.Stat_t, permitSocket bool) error { switch stat.Mode & syscall.S_IFMT { - case syscall.S_IFREG: - ft = regular - case syscall.S_IFDIR: - ft = directory - case syscall.S_IFLNK: - ft = symlink + case syscall.S_IFREG, syscall.S_IFDIR, syscall.S_IFLNK: + return nil + case syscall.S_IFSOCK: if !permitSocket { - return unknown, syscall.EPERM + return syscall.EPERM } - ft = socket + return nil + default: - return unknown, syscall.EPERM + return syscall.EPERM } - return ft, nil } func newLocalFile(a *attachPoint, file *fd.FD, path string, readable bool, stat syscall.Stat_t) (*localFile, error) { - ft, err := getSupportedFileType(stat, a.conf.HostUDS) - if err != nil { + if err := checkSupportedFileType(stat, a.conf.HostUDS); err != nil { return nil, err } @@ -339,7 +305,8 @@ func newLocalFile(a *attachPoint, file *fd.FD, path string, readable bool, stat hostPath: path, file: file, mode: invalidMode, - ft: ft, + fileType: stat.Mode & syscall.S_IFMT, + qid: a.makeQID(stat), controlReadable: readable, }, nil } @@ -359,7 +326,7 @@ func newFDMaybe(file *fd.FD) *fd.FD { // fd is blocking; non-blocking is required. if err := syscall.SetNonblock(dup.FD(), true); err != nil { - dup.Close() + _ = dup.Close() return nil } return dup @@ -409,16 +376,8 @@ func (l *localFile) Open(flags p9.OpenFlags) (*fd.FD, p9.QID, uint32, error) { } } - stat, err := fstat(newFile.FD()) - if err != nil { - if newFile != l.file { - newFile.Close() - } - return nil, p9.QID{}, 0, extractErrno(err) - } - var fd *fd.FD - if stat.Mode&syscall.S_IFMT == syscall.S_IFREG { + if l.fileType == syscall.S_IFREG { // Donate FD for regular files only. fd = newFDMaybe(newFile) } @@ -431,7 +390,7 @@ func (l *localFile) Open(flags p9.OpenFlags) (*fd.FD, p9.QID, uint32, error) { l.file = newFile } l.mode = flags & p9.OpenFlagsModeMask - return fd, l.attachPoint.makeQID(stat), 0, nil + return fd, l.qid, 0, nil } // Create implements p9.File. @@ -459,7 +418,7 @@ func (l *localFile) Create(name string, mode p9.OpenFlags, perm p9.FileMode, uid return nil, nil, p9.QID{}, 0, extractErrno(err) } cu := cleanup.Make(func() { - child.Close() + _ = child.Close() // Best effort attempt to remove the file in case of failure. if err := syscall.Unlinkat(l.file.FD(), name); err != nil { log.Warningf("error unlinking file %q after failure: %v", path.Join(l.hostPath, name), err) @@ -480,10 +439,12 @@ func (l *localFile) Create(name string, mode p9.OpenFlags, perm p9.FileMode, uid hostPath: path.Join(l.hostPath, name), file: child, mode: mode, + fileType: syscall.S_IFREG, + qid: l.attachPoint.makeQID(stat), } cu.Release() - return newFDMaybe(c.file), c, l.attachPoint.makeQID(stat), 0, nil + return newFDMaybe(c.file), c, c.qid, 0, nil } // Mkdir implements p9.File. @@ -529,19 +490,34 @@ func (l *localFile) Mkdir(name string, perm p9.FileMode, uid p9.UID, gid p9.GID) // Walk implements p9.File. func (l *localFile) Walk(names []string) ([]p9.QID, p9.File, error) { + qids, file, _, err := l.walk(names) + return qids, file, err +} + +// WalkGetAttr implements p9.File. +func (l *localFile) WalkGetAttr(names []string) ([]p9.QID, p9.File, p9.AttrMask, p9.Attr, error) { + qids, file, stat, err := l.walk(names) + if err != nil { + return nil, nil, p9.AttrMask{}, p9.Attr{}, err + } + mask, attr := l.fillAttr(stat) + return qids, file, mask, attr, nil +} + +func (l *localFile) walk(names []string) ([]p9.QID, p9.File, syscall.Stat_t, error) { // Duplicate current file if 'names' is empty. if len(names) == 0 { newFile, readable, err := openAnyFile(l.hostPath, func(mode int) (*fd.FD, error) { return reopenProcFd(l.file, openFlags|mode) }) if err != nil { - return nil, nil, extractErrno(err) + return nil, nil, syscall.Stat_t{}, extractErrno(err) } stat, err := fstat(newFile.FD()) if err != nil { - newFile.Close() - return nil, nil, extractErrno(err) + _ = newFile.Close() + return nil, nil, syscall.Stat_t{}, extractErrno(err) } c := &localFile{ @@ -549,36 +525,39 @@ func (l *localFile) Walk(names []string) ([]p9.QID, p9.File, error) { hostPath: l.hostPath, file: newFile, mode: invalidMode, + fileType: l.fileType, + qid: l.attachPoint.makeQID(stat), controlReadable: readable, } - return []p9.QID{l.attachPoint.makeQID(stat)}, c, nil + return []p9.QID{c.qid}, c, stat, nil } var qids []p9.QID + var lastStat syscall.Stat_t last := l for _, name := range names { f, path, readable, err := openAnyFileFromParent(last, name) if last != l { - last.Close() + _ = last.Close() } if err != nil { - return nil, nil, extractErrno(err) + return nil, nil, syscall.Stat_t{}, extractErrno(err) } - stat, err := fstat(f.FD()) + lastStat, err = fstat(f.FD()) if err != nil { - f.Close() - return nil, nil, extractErrno(err) + _ = f.Close() + return nil, nil, syscall.Stat_t{}, extractErrno(err) } - c, err := newLocalFile(last.attachPoint, f, path, readable, stat) + c, err := newLocalFile(last.attachPoint, f, path, readable, lastStat) if err != nil { - f.Close() - return nil, nil, extractErrno(err) + _ = f.Close() + return nil, nil, syscall.Stat_t{}, extractErrno(err) } - qids = append(qids, l.attachPoint.makeQID(stat)) + qids = append(qids, c.qid) last = c } - return qids, last, nil + return qids, last, lastStat, nil } // StatFS implements p9.File. @@ -618,12 +597,16 @@ func (l *localFile) GetAttr(_ p9.AttrMask) (p9.QID, p9.AttrMask, p9.Attr, error) if err != nil { return p9.QID{}, p9.AttrMask{}, p9.Attr{}, extractErrno(err) } + mask, attr := l.fillAttr(stat) + return l.qid, mask, attr, nil +} +func (l *localFile) fillAttr(stat syscall.Stat_t) (p9.AttrMask, p9.Attr) { attr := p9.Attr{ Mode: p9.FileMode(stat.Mode), UID: p9.UID(stat.Uid), GID: p9.GID(stat.Gid), - NLink: uint64(stat.Nlink), + NLink: stat.Nlink, RDev: stat.Rdev, Size: uint64(stat.Size), BlockSize: uint64(stat.Blksize), @@ -647,8 +630,7 @@ func (l *localFile) GetAttr(_ p9.AttrMask) (p9.QID, p9.AttrMask, p9.Attr, error) MTime: true, CTime: true, } - - return l.attachPoint.makeQID(stat), valid, attr, nil + return valid, attr } // SetAttr implements p9.File. Due to mismatch in file API, options @@ -689,7 +671,7 @@ func (l *localFile) SetAttr(valid p9.SetAttrMask, attr p9.SetAttr) error { // Check if it's possible to use cached file, or if another one needs to be // opened for write. f := l.file - if l.ft == regular && l.mode != p9.WriteOnly && l.mode != p9.ReadWrite { + if l.fileType == syscall.S_IFREG && l.mode != p9.WriteOnly && l.mode != p9.ReadWrite { var err error f, err = reopenProcFd(l.file, openFlags|os.O_WRONLY) if err != nil { @@ -745,7 +727,7 @@ func (l *localFile) SetAttr(valid p9.SetAttrMask, attr p9.SetAttr) error { } } - if l.ft == symlink { + if l.fileType == syscall.S_IFLNK { // utimensat operates different that other syscalls. To operate on a // symlink it *requires* AT_SYMLINK_NOFOLLOW with dirFD and a non-empty // name. @@ -929,7 +911,7 @@ func (l *localFile) Link(target p9.File, newName string) error { } // Mknod implements p9.File. -func (l *localFile) Mknod(name string, mode p9.FileMode, _ uint32, _ uint32, uid p9.UID, gid p9.GID) (p9.QID, error) { +func (l *localFile) Mknod(name string, mode p9.FileMode, _ uint32, _ uint32, _ p9.UID, _ p9.GID) (p9.QID, error) { conf := l.attachPoint.conf if conf.ROMount { if conf.PanicOnWrite { @@ -1127,13 +1109,13 @@ func (l *localFile) Connect(flags p9.ConnectFlags) (*fd.FD, error) { } if err := syscall.SetNonblock(f, true); err != nil { - syscall.Close(f) + _ = syscall.Close(f) return nil, err } sa := syscall.SockaddrUnix{Name: l.hostPath} if err := syscall.Connect(f, &sa); err != nil { - syscall.Close(f) + _ = syscall.Close(f) return nil, err } |