seaweedfs/weed/filesys/wfs.go
2018-12-29 10:31:36 -08:00

187 lines
4.9 KiB
Go

package filesys
import (
"context"
"fmt"
"math"
"os"
"sync"
"time"
"github.com/seaweedfs/fuse"
"github.com/seaweedfs/fuse/fs"
"github.com/chrislusf/seaweedfs/weed/glog"
"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
"github.com/chrislusf/seaweedfs/weed/util"
"github.com/karlseguin/ccache"
"google.golang.org/grpc"
)
type Option struct {
FilerGrpcAddress string
FilerMountRootPath string
Collection string
Replication string
TtlSec int32
ChunkSizeLimit int64
DataCenter string
DirListingLimit int
EntryCacheTtl time.Duration
MountUid uint32
MountGid uint32
MountMode os.FileMode
}
var _ = fs.FS(&WFS{})
var _ = fs.FSStatfser(&WFS{})
type WFS struct {
option *Option
listDirectoryEntriesCache *ccache.Cache
// contains all open handles
handles []*FileHandle
pathToHandleIndex map[string]int
pathToHandleLock sync.Mutex
bufPool sync.Pool
stats statsCache
}
type statsCache struct {
filer_pb.StatisticsResponse
lastChecked int64 // unix time in seconds
}
func NewSeaweedFileSystem(option *Option) *WFS {
return &WFS{
option: option,
listDirectoryEntriesCache: ccache.New(ccache.Configure().MaxSize(int64(option.DirListingLimit) + 200).ItemsToPrune(100)),
pathToHandleIndex: make(map[string]int),
bufPool: sync.Pool{
New: func() interface{} {
return make([]byte, option.ChunkSizeLimit)
},
},
}
}
func (wfs *WFS) Root() (fs.Node, error) {
return &Dir{Path: wfs.option.FilerMountRootPath, wfs: wfs}, nil
}
func (wfs *WFS) withFilerClient(fn func(filer_pb.SeaweedFilerClient) error) error {
return util.WithCachedGrpcClient(func(grpcConnection *grpc.ClientConn) error {
client := filer_pb.NewSeaweedFilerClient(grpcConnection)
return fn(client)
}, wfs.option.FilerGrpcAddress)
}
func (wfs *WFS) AcquireHandle(file *File, uid, gid uint32) (fileHandle *FileHandle) {
wfs.pathToHandleLock.Lock()
defer wfs.pathToHandleLock.Unlock()
fullpath := file.fullpath()
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).Infoln(fullpath, "reuse fileHandle id", fileHandle.handle)
return
}
}
wfs.handles = append(wfs.handles, fileHandle)
fileHandle.handle = uint64(len(wfs.handles) - 1)
glog.V(2).Infoln(fullpath, "new fileHandle id", fileHandle.handle)
wfs.pathToHandleIndex[fullpath] = int(fileHandle.handle)
return
}
func (wfs *WFS) ReleaseHandle(fullpath string, handleId fuse.HandleID) {
wfs.pathToHandleLock.Lock()
defer wfs.pathToHandleLock.Unlock()
glog.V(4).Infof("%s releasing handle 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
}
return
}
// Statfs is called to obtain file system metadata. Implements fuse.FSStatfser
func (wfs *WFS) Statfs(ctx context.Context, req *fuse.StatfsRequest, resp *fuse.StatfsResponse) error {
glog.V(4).Infof("reading fs stats: %+v", req)
if wfs.stats.lastChecked < time.Now().Unix()-20 {
err := wfs.withFilerClient(func(client filer_pb.SeaweedFilerClient) error {
request := &filer_pb.StatisticsRequest{
Collection: wfs.option.Collection,
Replication: wfs.option.Replication,
Ttl: fmt.Sprintf("%ds", wfs.option.TtlSec),
}
glog.V(4).Infof("reading filer stats: %+v", request)
resp, err := client.Statistics(ctx, request)
if err != nil {
glog.V(0).Infof("reading filer stats %v: %v", request, err)
return err
}
glog.V(4).Infof("read filer stats: %+v", resp)
wfs.stats.TotalSize = resp.TotalSize
wfs.stats.UsedSize = resp.UsedSize
wfs.stats.FileCount = resp.FileCount
wfs.stats.lastChecked = time.Now().Unix()
return nil
})
if err != nil {
glog.V(0).Infof("filer Statistics: %v", err)
return err
}
}
totalDiskSize := wfs.stats.TotalSize
usedDiskSize := wfs.stats.UsedSize
actualFileCount := wfs.stats.FileCount
// Compute the total number of available blocks
resp.Blocks = totalDiskSize / blockSize
// Compute the number of used blocks
numblocks := uint64(usedDiskSize / blockSize)
// Report the number of free and available blocks for the block size
resp.Bfree = resp.Blocks - numblocks
resp.Bavail = resp.Blocks - numblocks
resp.Bsize = uint32(blockSize)
// Report the total number of possible files in the file system (and those free)
resp.Files = math.MaxInt64
resp.Ffree = math.MaxInt64 - actualFileCount
// Report the maximum length of a name and the minimum fragment size
resp.Namelen = 1024
resp.Frsize = uint32(blockSize)
return nil
}