Files
seaweedFS/weed/mount/weedfs_file_lseek.go
Chris Lu d4ecfaeda7 Enable writeback_cache and async_dio FUSE options (#7980)
* Enable writeback_cache and async_dio FUSE options

Fixes #7978

- Update mount_std.go to use EnableWriteback and EnableAsyncDio from go-fuse
- Add go.mod replace directive to use local go-fuse with capability support
- Remove temporary workaround that disabled these options

This enables proper FUSE kernel capability negotiation for writeback cache
and async direct I/O, improving performance for small writes and concurrent
direct I/O operations.

* Address PR review comments

- Remove redundant nil checks for writebackCache and asyncDio flags
- Update go.mod replace directive to use seaweedfs/go-fuse fork instead of local path

* Add TODO comment for go.mod replace directive

The replace directive must use a local path until seaweedfs/go-fuse#1 is merged.
After merge, this should be updated to use the proper version.

* Use seaweedfs/go-fuse v2.9.0 instead of local repository

Replace local path with seaweedfs/go-fuse v2.9.0 fork which includes
the writeback_cache and async_dio capability support.

* Use github.com/seaweedfs/go-fuse/v2 directly without replace directive

- Updated all imports to use github.com/seaweedfs/go-fuse/v2
- Removed replace directive from go.mod
- Using seaweedfs/go-fuse v2.0.0-20260106181308-87f90219ce09 which includes:
  * writeback_cache and async_dio support
  * Corrected module path

* Update to seaweedfs/go-fuse v2.9.1

Use v2.9.1 tag which includes the corrected module path
(github.com/seaweedfs/go-fuse/v2) along with writeback_cache
and async_dio support.
2026-01-06 10:50:54 -08:00

89 lines
2.3 KiB
Go

package mount
import (
"context"
"syscall"
"github.com/seaweedfs/seaweedfs/weed/util"
"github.com/seaweedfs/go-fuse/v2/fuse"
"github.com/seaweedfs/seaweedfs/weed/filer"
"github.com/seaweedfs/seaweedfs/weed/glog"
)
// These are non-POSIX extensions
const (
SEEK_DATA uint32 = 3 // seek to next data after the offset
SEEK_HOLE uint32 = 4 // seek to next hole after the offset
ENXIO = fuse.Status(syscall.ENXIO)
)
// Lseek finds next data or hole segments after the specified offset
// See https://man7.org/linux/man-pages/man2/lseek.2.html
func (wfs *WFS) Lseek(cancel <-chan struct{}, in *fuse.LseekIn, out *fuse.LseekOut) fuse.Status {
// not a documented feature
if in.Padding != 0 {
return fuse.EINVAL
}
if in.Whence != SEEK_DATA && in.Whence != SEEK_HOLE {
return fuse.EINVAL
}
// file must exist
fh := wfs.GetHandle(FileHandleId(in.Fh))
if fh == nil {
return fuse.EBADF
}
// lock the file until the proper offset was calculated
fhActiveLock := fh.wfs.fhLockTable.AcquireLock("Lseek", fh.fh, util.SharedLock)
defer fh.wfs.fhLockTable.ReleaseLock(fh.fh, fhActiveLock)
fileSize := int64(filer.FileSize(fh.GetEntry().GetEntry()))
offset := max(int64(in.Offset), 0)
glog.V(4).Infof(
"Lseek %s fh %d in [%d,%d], whence %d",
fh.FullPath(), fh.fh, offset, fileSize, in.Whence,
)
// can neither seek beyond file nor seek to a hole at the end of the file with SEEK_DATA
if offset > fileSize {
return ENXIO
} else if in.Whence == SEEK_DATA && offset == fileSize {
return ENXIO
}
// Create a context that will be cancelled when the cancel channel receives a signal
ctx, cancelFunc := context.WithCancel(context.Background())
defer cancelFunc() // Ensure cleanup
go func() {
select {
case <-cancel:
cancelFunc()
case <-ctx.Done():
// Clean exit when lseek operation completes
}
}()
// search chunks for the offset
found, offset := fh.entryChunkGroup.SearchChunks(ctx, offset, fileSize, in.Whence)
if found {
out.Offset = uint64(offset)
return fuse.OK
}
// in case we found no exact matches, we return the recommended fallbacks, that is:
// original offset for SEEK_DATA or end of file for an implicit hole
if in.Whence == SEEK_DATA {
out.Offset = in.Offset
} else {
out.Offset = uint64(fileSize)
}
return fuse.OK
}