rclone/cmd/mount/mount.go
Nick Craig-Wood 4cc2a7f342 mount: fix caching of old directories after renaming them
It was discovered `rclone mount` (but not `rclone cmount`) cached
directories after rename which it shouldn't have done.

This caused IO errors when trying to access files in renamed
directories on bucket based file systems.

This turned out to be the kernel caching the directories as basil/fuse
sets their expiry time to 60s for some reason.

This fix invalidates the relevant kernel cache entries in the for the
directories which fixes the problem.

Fixes: #4977
See: https://forum.rclone.org/t/after-a-directory-renmane-using-mv-files-are-not-visible-any-longer/22797
2021-03-22 09:07:01 +00:00

120 lines
3.1 KiB
Go

// Package mount implements a FUSE mounting system for rclone remotes.
// +build linux freebsd
package mount
import (
"fmt"
"runtime"
"bazil.org/fuse"
fusefs "bazil.org/fuse/fs"
"github.com/rclone/rclone/cmd/mountlib"
"github.com/rclone/rclone/fs"
"github.com/rclone/rclone/vfs"
)
func init() {
mountlib.NewMountCommand("mount", false, mount)
mountlib.AddRc("mount", mount)
}
// mountOptions configures the options from the command line flags
func mountOptions(VFS *vfs.VFS, device string, opt *mountlib.Options) (options []fuse.MountOption) {
options = []fuse.MountOption{
fuse.MaxReadahead(uint32(opt.MaxReadAhead)),
fuse.Subtype("rclone"),
fuse.FSName(device),
fuse.VolumeName(opt.VolumeName),
// Options from benchmarking in the fuse module
//fuse.MaxReadahead(64 * 1024 * 1024),
//fuse.WritebackCache(),
}
if opt.AsyncRead {
options = append(options, fuse.AsyncRead())
}
if opt.AllowNonEmpty {
options = append(options, fuse.AllowNonEmptyMount())
}
if opt.AllowOther {
options = append(options, fuse.AllowOther())
}
if opt.AllowRoot {
// options = append(options, fuse.AllowRoot())
fs.Errorf(nil, "Ignoring --allow-root. Support has been removed upstream - see https://github.com/bazil/fuse/issues/144 for more info")
}
if opt.DefaultPermissions {
options = append(options, fuse.DefaultPermissions())
}
if VFS.Opt.ReadOnly {
options = append(options, fuse.ReadOnly())
}
if opt.WritebackCache {
options = append(options, fuse.WritebackCache())
}
if opt.DaemonTimeout != 0 {
options = append(options, fuse.DaemonTimeout(fmt.Sprint(int(opt.DaemonTimeout.Seconds()))))
}
if len(opt.ExtraOptions) > 0 {
fs.Errorf(nil, "-o/--option not supported with this FUSE backend")
}
if len(opt.ExtraFlags) > 0 {
fs.Errorf(nil, "--fuse-flag not supported with this FUSE backend")
}
return options
}
// mount the file system
//
// The mount point will be ready when this returns.
//
// returns an error, and an error channel for the serve process to
// report an error when fusermount is called.
func mount(VFS *vfs.VFS, mountpoint string, opt *mountlib.Options) (<-chan error, func() error, error) {
if runtime.GOOS == "darwin" {
fs.Logf(nil, "macOS users: please try \"rclone cmount\" as it will be the default in v1.54")
}
if opt.DebugFUSE {
fuse.Debug = func(msg interface{}) {
fs.Debugf("fuse", "%v", msg)
}
}
f := VFS.Fs()
fs.Debugf(f, "Mounting on %q", mountpoint)
c, err := fuse.Mount(mountpoint, mountOptions(VFS, f.Name()+":"+f.Root(), opt)...)
if err != nil {
return nil, nil, err
}
filesys := NewFS(VFS, opt)
filesys.server = fusefs.New(c, nil)
// Serve the mount point in the background returning error to errChan
errChan := make(chan error, 1)
go func() {
err := filesys.server.Serve(filesys)
closeErr := c.Close()
if err == nil {
err = closeErr
}
errChan <- err
}()
// check if the mount process has an error to report
<-c.Ready
if err := c.MountError; err != nil {
return nil, nil, err
}
unmount := func() error {
// Shutdown the VFS
filesys.VFS.Shutdown()
return fuse.Unmount(mountpoint)
}
return errChan, unmount, nil
}