rclone/cmd/mount/dir.go
Nick Craig-Wood bfcd4113c3 mount: implement mknod to make NFS file creation work - fixes #2115
It turns out that NFS calls mknod in FUSE even though we have create
defined. This was causing EIO errors when creating files.

This patch fixes it by implementing mknod. The way it is implemented
means that to write to an NFS file system you'll need --vfs-cache-mode
writes.
2020-10-29 15:12:36 +00:00

247 lines
6.9 KiB
Go

// +build linux,go1.13 freebsd,go1.13
package mount
import (
"context"
"io"
"os"
"time"
"bazil.org/fuse"
fusefs "bazil.org/fuse/fs"
"github.com/pkg/errors"
"github.com/rclone/rclone/cmd/mountlib"
"github.com/rclone/rclone/fs"
"github.com/rclone/rclone/fs/log"
"github.com/rclone/rclone/vfs"
)
// Dir represents a directory entry
type Dir struct {
*vfs.Dir
fsys *FS
}
// Check interface satisfied
var _ fusefs.Node = (*Dir)(nil)
// Attr updates the attributes of a directory
func (d *Dir) Attr(ctx context.Context, a *fuse.Attr) (err error) {
defer log.Trace(d, "")("attr=%+v, err=%v", a, &err)
a.Valid = d.fsys.opt.AttrTimeout
a.Gid = d.VFS().Opt.GID
a.Uid = d.VFS().Opt.UID
a.Mode = os.ModeDir | d.VFS().Opt.DirPerms
modTime := d.ModTime()
a.Atime = modTime
a.Mtime = modTime
a.Ctime = modTime
a.Crtime = modTime
// FIXME include Valid so get some caching?
// FIXME fs.Debugf(d.path, "Dir.Attr %+v", a)
return nil
}
// Check interface satisfied
var _ fusefs.NodeSetattrer = (*Dir)(nil)
// Setattr handles attribute changes from FUSE. Currently supports ModTime only.
func (d *Dir) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *fuse.SetattrResponse) (err error) {
defer log.Trace(d, "stat=%+v", req)("err=%v", &err)
if d.VFS().Opt.NoModTime {
return nil
}
if req.Valid.MtimeNow() {
err = d.SetModTime(time.Now())
} else if req.Valid.Mtime() {
err = d.SetModTime(req.Mtime)
}
return translateError(err)
}
// Check interface satisfied
var _ fusefs.NodeRequestLookuper = (*Dir)(nil)
// Lookup looks up a specific entry in the receiver.
//
// Lookup should return a Node corresponding to the entry. If the
// name does not exist in the directory, Lookup should return ENOENT.
//
// Lookup need not to handle the names "." and "..".
func (d *Dir) Lookup(ctx context.Context, req *fuse.LookupRequest, resp *fuse.LookupResponse) (node fusefs.Node, err error) {
defer log.Trace(d, "name=%q", req.Name)("node=%+v, err=%v", &node, &err)
mnode, err := d.Dir.Stat(req.Name)
if err != nil {
return nil, translateError(err)
}
resp.EntryValid = d.fsys.opt.AttrTimeout
// Check the mnode to see if it has a fuse Node cached
// We must return the same fuse nodes for vfs Nodes
node, ok := mnode.Sys().(fusefs.Node)
if ok {
return node, nil
}
switch x := mnode.(type) {
case *vfs.File:
node = &File{x, d.fsys}
case *vfs.Dir:
node = &Dir{x, d.fsys}
default:
panic("bad type")
}
// Cache the node for later
mnode.SetSys(node)
return node, nil
}
// Check interface satisfied
var _ fusefs.HandleReadDirAller = (*Dir)(nil)
// ReadDirAll reads the contents of the directory
func (d *Dir) ReadDirAll(ctx context.Context) (dirents []fuse.Dirent, err error) {
itemsRead := -1
defer log.Trace(d, "")("item=%d, err=%v", &itemsRead, &err)
items, err := d.Dir.ReadDirAll()
if err != nil {
return nil, translateError(err)
}
for _, node := range items {
name := node.Name()
if len(name) > mountlib.MaxLeafSize {
fs.Errorf(d, "Name too long (%d bytes) for FUSE, skipping: %s", len(name), name)
continue
}
var dirent = fuse.Dirent{
// Inode FIXME ???
Type: fuse.DT_File,
Name: name,
}
if node.IsDir() {
dirent.Type = fuse.DT_Dir
}
dirents = append(dirents, dirent)
}
itemsRead = len(dirents)
return dirents, nil
}
var _ fusefs.NodeCreater = (*Dir)(nil)
// Create makes a new file
func (d *Dir) Create(ctx context.Context, req *fuse.CreateRequest, resp *fuse.CreateResponse) (node fusefs.Node, handle fusefs.Handle, err error) {
defer log.Trace(d, "name=%q", req.Name)("node=%v, handle=%v, err=%v", &node, &handle, &err)
file, err := d.Dir.Create(req.Name, int(req.Flags))
if err != nil {
return nil, nil, translateError(err)
}
fh, err := file.Open(int(req.Flags) | os.O_CREATE)
if err != nil {
return nil, nil, translateError(err)
}
node = &File{file, d.fsys}
file.SetSys(node) // cache the FUSE node for later
return node, &FileHandle{fh}, err
}
var _ fusefs.NodeMkdirer = (*Dir)(nil)
// Mkdir creates a new directory
func (d *Dir) Mkdir(ctx context.Context, req *fuse.MkdirRequest) (node fusefs.Node, err error) {
defer log.Trace(d, "name=%q", req.Name)("node=%+v, err=%v", &node, &err)
dir, err := d.Dir.Mkdir(req.Name)
if err != nil {
return nil, translateError(err)
}
node = &Dir{dir, d.fsys}
dir.SetSys(node) // cache the FUSE node for later
return node, nil
}
var _ fusefs.NodeRemover = (*Dir)(nil)
// Remove removes the entry with the given name from
// the receiver, which must be a directory. The entry to be removed
// may correspond to a file (unlink) or to a directory (rmdir).
func (d *Dir) Remove(ctx context.Context, req *fuse.RemoveRequest) (err error) {
defer log.Trace(d, "name=%q", req.Name)("err=%v", &err)
err = d.Dir.RemoveName(req.Name)
if err != nil {
return translateError(err)
}
return nil
}
// Check interface satisfied
var _ fusefs.NodeRenamer = (*Dir)(nil)
// Rename the file
func (d *Dir) Rename(ctx context.Context, req *fuse.RenameRequest, newDir fusefs.Node) (err error) {
defer log.Trace(d, "oldName=%q, newName=%q, newDir=%+v", req.OldName, req.NewName, newDir)("err=%v", &err)
destDir, ok := newDir.(*Dir)
if !ok {
return errors.Errorf("Unknown Dir type %T", newDir)
}
err = d.Dir.Rename(req.OldName, req.NewName, destDir.Dir)
if err != nil {
return translateError(err)
}
return nil
}
// Check interface satisfied
var _ fusefs.NodeFsyncer = (*Dir)(nil)
// Fsync the directory
func (d *Dir) Fsync(ctx context.Context, req *fuse.FsyncRequest) (err error) {
defer log.Trace(d, "")("err=%v", &err)
err = d.Dir.Sync()
if err != nil {
return translateError(err)
}
return nil
}
// Check interface satisfied
var _ fusefs.NodeLinker = (*Dir)(nil)
// Link creates a new directory entry in the receiver based on an
// existing Node. Receiver must be a directory.
func (d *Dir) Link(ctx context.Context, req *fuse.LinkRequest, old fusefs.Node) (newNode fusefs.Node, err error) {
defer log.Trace(d, "req=%v, old=%v", req, old)("new=%v, err=%v", &newNode, &err)
return nil, fuse.ENOSYS
}
// Check interface satisfied
var _ fusefs.NodeMknoder = (*Dir)(nil)
// Mknod is called to create a file. Since we define create this will
// be called in preference, however NFS likes to call it for some
// reason. We don't actually create a file here just the Node.
func (d *Dir) Mknod(ctx context.Context, req *fuse.MknodRequest) (node fusefs.Node, err error) {
defer log.Trace(d, "name=%v, mode=%d, rdev=%d", req.Name, req.Mode, req.Rdev)("node=%v, err=%v", &node, &err)
if req.Rdev != 0 {
fs.Errorf(d, "Can't create device node %q", req.Name)
return nil, fuse.EIO
}
var cReq = fuse.CreateRequest{
Name: req.Name,
Flags: fuse.OpenFlags(os.O_CREATE | os.O_WRONLY),
Mode: req.Mode,
Umask: req.Umask,
}
var cResp fuse.CreateResponse
node, handle, err := d.Create(ctx, &cReq, &cResp)
if err != nil {
return nil, err
}
err = handle.(io.Closer).Close()
if err != nil {
return nil, err
}
return node, nil
}