From db22e54fa3a4a9326778f1acc15d1178d3bbe11b Mon Sep 17 00:00:00 2001
From: Alex Yatskov <alex@foosoft.net>
Date: Mon, 6 Jul 2015 17:42:37 +0900
Subject: [PATCH] Revert "Kill the mutexes, don't seem to be required"

This reverts commit 1ba41be529d306db81e13ecf55dc45922120cfa6.
---
 dir.go  | 23 ++++++++++++++++++++++-
 file.go | 13 ++++++++++++-
 meta.go | 10 +++++++++-
 3 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/dir.go b/dir.go
index 755e5b3..35da465 100644
--- a/dir.go
+++ b/dir.go
@@ -26,6 +26,7 @@ import (
 	"errors"
 	"os"
 	"path"
+	"sync"
 
 	"bazil.org/fuse"
 	"bazil.org/fuse/fs"
@@ -42,16 +43,20 @@ type verDir struct {
 	node   *verNode
 	inode  uint64
 	parent *verDir
+	mutex  sync.Mutex
 }
 
 func newVerDir(node *verNode, parent *verDir) *verDir {
 	dirs := make(map[string]*verDir)
 	files := make(map[string]*verFile)
 
-	return &verDir{dirs, files, node, allocInode(), parent}
+	return &verDir{dirs, files, node, allocInode(), parent, sync.Mutex{}}
 }
 
 func (vd *verDir) version() error {
+	vd.mutex.Lock()
+	defer vd.mutex.Unlock()
+
 	if vd.node.flags&NodeFlagNew == NodeFlagNew {
 		return nil
 	}
@@ -80,7 +85,9 @@ func (vd *verDir) createDir(name string) (*verDir, error) {
 	node := newVerNode(childPath, vd.node.ver, nil, NodeFlagDir|NodeFlagNew)
 	dir := newVerDir(node, vd)
 
+	vd.mutex.Lock()
 	vd.dirs[name] = dir
+	vd.mutex.Unlock()
 
 	node.ver.meta.createNode(node.path)
 	return dir, nil
@@ -100,13 +107,18 @@ func (vd *verDir) createFile(name string, flags fuse.OpenFlags, mode os.FileMode
 		return nil, nil, 0, err
 	}
 
+	vd.mutex.Lock()
 	vd.files[name] = file
+	vd.mutex.Unlock()
 
 	node.ver.meta.createNode(node.path)
 	return file, handle, id, nil
 }
 
 func (vd *verDir) removeDir(name string) error {
+	vd.mutex.Lock()
+	defer vd.mutex.Unlock()
+
 	if err := vd.version(); err != nil {
 		return err
 	}
@@ -125,6 +137,9 @@ func (vd *verDir) removeDir(name string) error {
 }
 
 func (vd *verDir) removeFile(name string) error {
+	vd.mutex.Lock()
+	defer vd.mutex.Unlock()
+
 	if err := vd.version(); err != nil {
 		return err
 	}
@@ -193,6 +208,9 @@ func (vd *verDir) Remove(ctx context.Context, req *fuse.RemoveRequest) error {
 
 // NodeRequestLookuper
 func (vd *verDir) Lookup(ctx context.Context, name string) (fs.Node, error) {
+	vd.mutex.Lock()
+	defer vd.mutex.Unlock()
+
 	if dir, ok := vd.dirs[name]; ok {
 		return dir, nil
 	}
@@ -206,6 +224,9 @@ func (vd *verDir) Lookup(ctx context.Context, name string) (fs.Node, error) {
 
 // HandleReadDirAller
 func (vd *verDir) ReadDirAll(ctx context.Context) ([]fuse.Dirent, error) {
+	vd.mutex.Lock()
+	defer vd.mutex.Unlock()
+
 	entries := []fuse.Dirent{{Inode: vd.inode, Name: ".", Type: fuse.DT_Dir}}
 	if vd.parent != nil {
 		entry := fuse.Dirent{Inode: vd.parent.inode, Name: "..", Type: fuse.DT_Dir}
diff --git a/file.go b/file.go
index 696c4df..77ae9c2 100644
--- a/file.go
+++ b/file.go
@@ -24,6 +24,7 @@ package main
 
 import (
 	"os"
+	"sync"
 
 	"bazil.org/fuse"
 	"bazil.org/fuse/fs"
@@ -41,13 +42,17 @@ type verFile struct {
 	inode   uint64
 	parent  *verDir
 	handles handleMap
+	mutex   sync.Mutex
 }
 
 func newVerFile(node *verNode, parent *verDir) *verFile {
-	return &verFile{node, allocInode(), parent, make(handleMap)}
+	return &verFile{node, allocInode(), parent, make(handleMap), sync.Mutex{}}
 }
 
 func (vf *verFile) version() error {
+	vf.mutex.Lock()
+	defer vf.mutex.Unlock()
+
 	if vf.node.flags&NodeFlagNew == NodeFlagNew {
 		return nil
 	}
@@ -80,13 +85,17 @@ func (vf *verFile) open(flags fuse.OpenFlags, mode os.FileMode) (*verFileHandle,
 	id := allocHandleId()
 	verHandle := &verFileHandle{vf, path, handle}
 
+	vf.mutex.Lock()
 	vf.handles[id] = verHandle
+	vf.mutex.Unlock()
 
 	return verHandle, id, nil
 }
 
 func (vf *verFile) release(handle fuse.HandleID) {
+	vf.mutex.Lock()
 	delete(vf.handles, handle)
+	vf.mutex.Unlock()
 }
 
 // Node
@@ -119,6 +128,8 @@ func (vf *verFile) Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.O
 
 // NodeFsyncer
 func (vf *verFile) Fsync(ctx context.Context, req *fuse.FsyncRequest) error {
+	vf.mutex.Lock()
+	defer vf.mutex.Unlock()
 	return vf.handles[req.Handle].handle.Sync()
 }
 
diff --git a/meta.go b/meta.go
index d3f9bbc..4ebbb8a 100644
--- a/meta.go
+++ b/meta.go
@@ -28,6 +28,7 @@ import (
 	"os"
 	"path"
 	"strings"
+	"sync"
 )
 
 //
@@ -42,10 +43,11 @@ type verMeta struct {
 	path     string
 	deleted  map[string]bool
 	modified bool
+	mutex    sync.Mutex
 }
 
 func newVerMeta(path string) (*verMeta, error) {
-	meta := &verMeta{path, make(map[string]bool), false}
+	meta := &verMeta{path, make(map[string]bool), false, sync.Mutex{}}
 	if err := meta.load(); err != nil {
 		return nil, err
 	}
@@ -68,12 +70,18 @@ func (m *verMeta) filter(nodes verNodeMap) {
 }
 
 func (m *verMeta) removeNode(path string) {
+	m.mutex.Lock()
 	m.deleted[path] = true
+	m.mutex.Unlock()
+
 	m.modified = true
 }
 
 func (m *verMeta) createNode(path string) {
+	m.mutex.Lock()
 	m.deleted[path] = false
+	m.mutex.Unlock()
+
 	m.modified = true
 }