mount: read data that is just written

able read on data not flushed
multiple file open shares the same file handle

fix https://github.com/chrislusf/seaweedfs/issues/1182 on linux

weed/filesys/dir.go

@@ -146,9 +146,8 @@ func (dir *Dir) Create(ctx context.Context, req *fuse.CreateRequest,
 	}
 
 	file := node.(*File)
-	file.isOpen = true
+	file.isOpen++
 	fh := dir.wfs.AcquireHandle(file, req.Uid, req.Gid)
-	fh.dirtyMetadata = true
 	return file, fh, nil
 
 }

weed/filesys/dirty_page.go

@@ -222,3 +222,26 @@ func max(x, y int64) int64 {
 	}
 	return y
 }
+func min(x, y int64) int64 {
+	if x < y {
+		return x
+	}
+	return y
+}
+
+func (pages *ContinuousDirtyPages) ReadDirtyData(ctx context.Context, data []byte, startOffset int64) (offset int64, size int, err error) {
+	bufSize := int64(len(data))
+	if startOffset+bufSize < pages.Offset {
+		return
+	}
+	if startOffset >= pages.Offset+pages.Size {
+		return
+	}
+
+	offset = max(pages.Offset, startOffset)
+	stopOffset := min(pages.Offset+pages.Size, startOffset+bufSize)
+	size = int(stopOffset - offset)
+	copy(data[offset-startOffset:], pages.Data[offset-pages.Offset:stopOffset-pages.Offset])
+
+	return
+}

weed/filesys/file.go

@@ -31,7 +31,7 @@ type File struct {
 	wfs            *WFS
 	entry          *filer_pb.Entry
 	entryViewCache []filer2.VisibleInterval
-	isOpen         bool
+	isOpen         int
 }
 
 func (file *File) fullpath() filer2.FullPath {
@@ -42,7 +42,7 @@ func (file *File) Attr(ctx context.Context, attr *fuse.Attr) error {
 
 	glog.V(4).Infof("file Attr %s, open:%v, existing attr: %+v", file.fullpath(), file.isOpen, attr)
 
-	if !file.isOpen {
+	if file.isOpen <=0 {
 		if err := file.maybeLoadEntry(ctx); err != nil {
 			return err
 		}
@@ -52,7 +52,7 @@ func (file *File) Attr(ctx context.Context, attr *fuse.Attr) error {
 	attr.Valid = time.Second
 	attr.Mode = os.FileMode(file.entry.Attributes.FileMode)
 	attr.Size = filer2.TotalSize(file.entry.Chunks)
-	if file.isOpen {
+	if file.isOpen > 0 {
 		attr.Size = file.entry.Attributes.FileSize
 	}
 	attr.Crtime = time.Unix(file.entry.Attributes.Crtime, 0)
@@ -81,7 +81,7 @@ func (file *File) Open(ctx context.Context, req *fuse.OpenRequest, resp *fuse.Op
 
 	glog.V(4).Infof("file %v open %+v", file.fullpath(), req)
 
-	file.isOpen = true
+	file.isOpen++
 
 	handle := file.wfs.AcquireHandle(file, req.Uid, req.Gid)
 
@@ -140,7 +140,7 @@ func (file *File) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *f
 		file.entry.Attributes.Mtime = req.Mtime.Unix()
 	}
 
-	if file.isOpen {
+	if file.isOpen > 0 {
 		return nil
 	}
 
@@ -218,7 +218,7 @@ func (file *File) Forget() {
 }
 
 func (file *File) maybeLoadEntry(ctx context.Context) error {
-	if file.entry == nil || !file.isOpen {
+	if file.entry == nil || file.isOpen <= 0{
 		entry, err := file.wfs.maybeLoadEntry(ctx, file.dir.Path, file.Name)
 		if err != nil {
 			return err

weed/filesys/filehandle.go

@@ -7,10 +7,11 @@ import (
 	"path"
 	"time"
 
+	"github.com/gabriel-vasile/mimetype"
+
 	"github.com/chrislusf/seaweedfs/weed/filer2"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
-	"github.com/gabriel-vasile/mimetype"
 	"github.com/seaweedfs/fuse"
 	"github.com/seaweedfs/fuse/fs"
 )
@@ -50,29 +51,50 @@ func (fh *FileHandle) Read(ctx context.Context, req *fuse.ReadRequest, resp *fus
 
 	glog.V(4).Infof("%s read fh %d: [%d,%d)", fh.f.fullpath(), fh.handle, req.Offset, req.Offset+int64(req.Size))
 
+	buff := make([]byte, req.Size)
+
+	totalRead, err := fh.readFromChunks(ctx, buff, req.Offset)
+	if err == nil {
+		dirtyOffset, dirtySize, dirtyReadErr := fh.readFromDirtyPages(ctx, buff, req.Offset)
+		if dirtyReadErr == nil && totalRead+req.Offset < dirtyOffset+int64(dirtySize) {
+			totalRead = dirtyOffset + int64(dirtySize) - req.Offset
+		}
+	}
+
+	resp.Data = buff[:totalRead]
+
+	if err != nil {
+		glog.Errorf("file handle read %s: %v", fh.f.fullpath(), err)
+	}
+
+	return err
+}
+
+func (fh *FileHandle) readFromDirtyPages(ctx context.Context, buff []byte, startOffset int64) (offset int64, size int, err error) {
+	return fh.dirtyPages.ReadDirtyData(ctx, buff, startOffset)
+}
+
+func (fh *FileHandle) readFromChunks(ctx context.Context, buff []byte, offset int64) (int64, error) {
+
 	// this value should come from the filer instead of the old f
 	if len(fh.f.entry.Chunks) == 0 {
 		glog.V(1).Infof("empty fh %v/%v", fh.f.dir.Path, fh.f.Name)
-		return nil
+		return 0, nil
 	}
 
-	buff := make([]byte, req.Size)
-
 	if fh.f.entryViewCache == nil {
 		fh.f.entryViewCache = filer2.NonOverlappingVisibleIntervals(fh.f.entry.Chunks)
 	}
 
-	chunkViews := filer2.ViewFromVisibleIntervals(fh.f.entryViewCache, req.Offset, req.Size)
-
-	totalRead, err := filer2.ReadIntoBuffer(ctx, fh.f.wfs, fh.f.fullpath(), buff, chunkViews, req.Offset)
+	chunkViews := filer2.ViewFromVisibleIntervals(fh.f.entryViewCache, offset, len(buff))
 
-	resp.Data = buff[:totalRead]
+	totalRead, err := filer2.ReadIntoBuffer(ctx, fh.f.wfs, fh.f.fullpath(), buff, chunkViews, offset)
 
 	if err != nil {
 		glog.Errorf("file handle read %s: %v", fh.f.fullpath(), err)
 	}
 
-	return err
+	return totalRead, err
 }
 
 // Write to the file handle
@@ -115,11 +137,12 @@ func (fh *FileHandle) Release(ctx context.Context, req *fuse.ReleaseRequest) err
 
 	glog.V(4).Infof("%v release fh %d", fh.f.fullpath(), fh.handle)
 
-	fh.dirtyPages.releaseResource()
+	fh.f.isOpen--
 
-	fh.f.wfs.ReleaseHandle(fh.f.fullpath(), fuse.HandleID(fh.handle))
-
-	fh.f.isOpen = false
+	if fh.f.isOpen <= 0 {
+		fh.dirtyPages.releaseResource()
+		fh.f.wfs.ReleaseHandle(fh.f.fullpath(), fuse.HandleID(fh.handle))
+	}
 
 	return nil
 }
@@ -141,7 +164,7 @@ func (fh *FileHandle) Flush(ctx context.Context, req *fuse.FlushRequest) error {
 		return nil
 	}
 
-	return fh.f.wfs.WithFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
+	err = fh.f.wfs.WithFilerClient(ctx, func(client filer_pb.SeaweedFilerClient) error {
 
 		if fh.f.entry.Attributes != nil {
 			fh.f.entry.Attributes.Mime = fh.contentType
@@ -178,4 +201,10 @@ func (fh *FileHandle) Flush(ctx context.Context, req *fuse.FlushRequest) error {
 
 		return nil
 	})
+
+	if err == nil {
+		fh.dirtyMetadata = false
+	}
+
+	return err
 }

weed/filesys/wfs.go

@@ -49,6 +49,7 @@ type WFS struct {
 	// contains all open handles, protected by handlesLock
 	handlesLock sync.Mutex
 	handles     []*FileHandle
+	pathToHandleIndex map[filer2.FullPath]int
 
 	bufPool sync.Pool
 
@@ -68,6 +69,7 @@ func NewSeaweedFileSystem(option *Option) *WFS {
 	wfs := &WFS{
 		option:                    option,
 		listDirectoryEntriesCache: ccache.New(ccache.Configure().MaxSize(option.DirListCacheLimit * 3).ItemsToPrune(100)),
+		pathToHandleIndex:         make(map[filer2.FullPath]int),
 		bufPool: sync.Pool{
 			New: func() interface{} {
 				return make([]byte, option.ChunkSizeLimit)
@@ -102,11 +104,18 @@ func (wfs *WFS) AcquireHandle(file *File, uid, gid uint32) (fileHandle *FileHand
 	wfs.handlesLock.Lock()
 	defer wfs.handlesLock.Unlock()
 
+	index, found := wfs.pathToHandleIndex[fullpath]
+	if found && wfs.handles[index] != nil {
+		glog.V(2).Infoln(fullpath, "found fileHandle id", index)
+		return wfs.handles[index]
+	}
+
 	fileHandle = newFileHandle(file, uid, gid)
 	for i, h := range wfs.handles {
 		if h == nil {
 			wfs.handles[i] = fileHandle
 			fileHandle.handle = uint64(i)
+			wfs.pathToHandleIndex[fullpath] = i
 			glog.V(4).Infof( "%s reuse fh %d", fullpath,fileHandle.handle)
 			return
 		}
@@ -114,6 +123,7 @@ func (wfs *WFS) AcquireHandle(file *File, uid, gid uint32) (fileHandle *FileHand
 
 	wfs.handles = append(wfs.handles, fileHandle)
 	fileHandle.handle = uint64(len(wfs.handles) - 1)
+	wfs.pathToHandleIndex[fullpath] = int(fileHandle.handle)
 	glog.V(4).Infof( "%s new fh %d", fullpath,fileHandle.handle)
 
 	return
@@ -124,6 +134,7 @@ func (wfs *WFS) ReleaseHandle(fullpath filer2.FullPath, handleId fuse.HandleID)
 	defer wfs.handlesLock.Unlock()
 
 	glog.V(4).Infof("%s ReleaseHandle id %d current handles length %d", fullpath, handleId, len(wfs.handles))
+	delete(wfs.pathToHandleIndex, fullpath)
 	if int(handleId) < len(wfs.handles) {
 		wfs.handles[int(handleId)] = nil
 	}