package mount import ( "context" "net/http" "github.com/hanwen/go-fuse/v2/fuse" "github.com/seaweedfs/seaweedfs/weed/glog" ) // CopyFileRange copies data from one file to another from and to specified offsets. // // See https://man7.org/linux/man-pages/man2/copy_file_range.2.html // See https://github.com/libfuse/libfuse/commit/fe4f9428fc403fa8b99051f52d84ea5bd13f3855 /** * Copy a range of data from one file to another * * Niels de Vos: • libfuse: add copy_file_range() support * * Performs an optimized copy between two file descriptors without the * additional cost of transferring data through the FUSE kernel module * to user space (glibc) and then back into the FUSE filesystem again. * * In case this method is not implemented, applications are expected to * fall back to a regular file copy. (Some glibc versions did this * emulation automatically, but the emulation has been removed from all * glibc release branches.) */ func (wfs *WFS) CopyFileRange(cancel <-chan struct{}, in *fuse.CopyFileRangeIn) (written uint32, code fuse.Status) { // flags must equal 0 for this syscall as of now if in.Flags != 0 { return 0, fuse.EINVAL } // files must exist fhOut := wfs.GetHandle(FileHandleId(in.FhOut)) if fhOut == nil { return 0, fuse.EBADF } fhIn := wfs.GetHandle(FileHandleId(in.FhIn)) if fhIn == nil { return 0, fuse.EBADF } // lock source and target file handles fhOut.orderedMutex.Acquire(context.Background(), 1) defer fhOut.orderedMutex.Release(1) if fhOut.entry == nil { return 0, fuse.ENOENT } if fhIn.fh != fhOut.fh { fhIn.orderedMutex.Acquire(context.Background(), 1) defer fhIn.orderedMutex.Release(1) } // directories are not supported if fhIn.entry.IsDirectory || fhOut.entry.IsDirectory { return 0, fuse.EISDIR } glog.V(4).Infof( "CopyFileRange %s fhIn %d -> %s fhOut %d, [%d,%d) -> [%d,%d)", fhIn.FullPath(), fhIn.fh, fhOut.FullPath(), fhOut.fh, in.OffIn, in.OffIn+in.Len, in.OffOut, in.OffOut+in.Len, ) data := make([]byte, in.Len) totalRead, err := readDataByFileHandle(data, fhIn, int64(in.OffIn)) if err != nil { glog.Warningf("file handle read %s %d: %v", fhIn.FullPath(), totalRead, err) return 0, fuse.EIO } data = data[:totalRead] if totalRead == 0 { return 0, fuse.OK } // put data at the specified offset in target file fhOut.dirtyPages.writerPattern.MonitorWriteAt(int64(in.OffOut), int(in.Len)) fhOut.entry.Content = nil fhOut.dirtyPages.AddPage(int64(in.OffOut), data, fhOut.dirtyPages.writerPattern.IsSequentialMode()) fhOut.entry.Attributes.FileSize = uint64(max(int64(in.OffOut)+totalRead, int64(fhOut.entry.Attributes.FileSize))) fhOut.dirtyMetadata = true written = uint32(totalRead) // detect mime type if written > 0 && in.OffOut <= 512 { fhOut.contentType = http.DetectContentType(data) } return written, fuse.OK }