text: /** @file
    FUSE_MKDIR wrapper for the Virtio Filesystem device.
  
    Copyright (C) 2020, Red Hat, Inc.
  
    SPDX-License-Identifier: BSD-2-Clause-Patent
  **/
  
  #include <Library/BaseLib.h> // AsciiStrSize()
  
  #include "VirtioFsDxe.h"
  
  /**
    Send a FUSE_MKDIR request to the Virtio Filesystem device, for creating a
    directory.
  
    The function may only be called after VirtioFsFuseInitSession() returns
    successfully and before VirtioFsUninit() is called.
  
    @param[in,out] VirtioFs  The Virtio Filesystem device to send the FUSE_MKDIR
                             request to. On output, the FUSE request counter
                             "VirtioFs->RequestId" will have been incremented.
  
    @param[in] ParentNodeId  The inode number of the direct parent directory of
                             the directory to create.
  
    @param[in] Name          The single-component filename of the directory to
                             create, under the parent directory identified by
                             ParentNodeId.
  
    @param[out] NodeId       The inode number of the new directory.
  
    @retval EFI_SUCCESS  The directory has been created.
  
    @return              The "errno" value mapped to an EFI_STATUS code, if the
                         Virtio Filesystem device explicitly reported an error.
  
    @return              Error codes propagated from VirtioFsSgListsValidate(),
                         VirtioFsFuseNewRequest(), VirtioFsSgListsSubmit(),
                         VirtioFsFuseCheckResponse().
  **/
  EFI_STATUS
  VirtioFsFuseMkDir (
    IN OUT VIRTIO_FS  *VirtioFs,
    IN     UINT64     ParentNodeId,
    IN     CHAR8      *Name,
    OUT UINT64        *NodeId
    )
  {
    VIRTIO_FS_FUSE_REQUEST              CommonReq;
    VIRTIO_FS_FUSE_MKDIR_REQUEST        MkDirReq;
    VIRTIO_FS_IO_VECTOR                 ReqIoVec[3];
    VIRTIO_FS_SCATTER_GATHER_LIST       ReqSgList;
    VIRTIO_FS_FUSE_RESPONSE             CommonResp;
    VIRTIO_FS_FUSE_NODE_RESPONSE        NodeResp;
    VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE  AttrResp;
    VIRTIO_FS_IO_VECTOR                 RespIoVec[3];
    VIRTIO_FS_SCATTER_GATHER_LIST       RespSgList;
    EFI_STATUS                          Status;
  
    //
    // Set up the scatter-gather lists.
    //
    ReqIoVec[0].Buffer = &CommonReq;
    ReqIoVec[0].Size   = sizeof CommonReq;
    ReqIoVec[1].Buffer = &MkDirReq;
    ReqIoVec[1].Size   = sizeof MkDirReq;
    ReqIoVec[2].Buffer = Name;
    ReqIoVec[2].Size   = AsciiStrSize (Name);
    ReqSgList.IoVec    = ReqIoVec;
    ReqSgList.NumVec   = ARRAY_SIZE (ReqIoVec);
  
    RespIoVec[0].Buffer = &CommonResp;
    RespIoVec[0].Size   = sizeof CommonResp;
    RespIoVec[1].Buffer = &NodeResp;
    RespIoVec[1].Size   = sizeof NodeResp;
    RespIoVec[2].Buffer = &AttrResp;
    RespIoVec[2].Size   = sizeof AttrResp;
    RespSgList.IoVec    = RespIoVec;
    RespSgList.NumVec   = ARRAY_SIZE (RespIoVec);
  
    //
    // Validate the scatter-gather lists; calculate the total transfer sizes.
    //
    Status = VirtioFsSgListsValidate (VirtioFs, &ReqSgList, &RespSgList);
    if (EFI_ERROR (Status)) {
      return Status;
    }
  
    //
    // Populate the common request header.
    //
    Status = VirtioFsFuseNewRequest (
               VirtioFs,
               &CommonReq,
               ReqSgList.TotalSize,
               VirtioFsFuseOpMkDir,
               ParentNodeId
               );
    if (EFI_ERROR (Status)) {
      return Status;
    }
  
    //
    // Populate the FUSE_MKDIR-specific fields.
    //
    MkDirReq.Mode = (VIRTIO_FS_FUSE_MODE_PERM_RWXU |
                     VIRTIO_FS_FUSE_MODE_PERM_RWXG |
                     VIRTIO_FS_FUSE_MODE_PERM_RWXO);
    MkDirReq.Umask = 0;
  
    //
    // Submit the request.
    //
    Status = VirtioFsSgListsSubmit (VirtioFs, &ReqSgList, &RespSgList);
    if (EFI_ERROR (Status)) {
      return Status;
    }
  
    //
    // Verify the response (all response buffers are fixed size).
    //
    Status = VirtioFsFuseCheckResponse (&RespSgList, CommonReq.Unique, NULL);
    if (EFI_ERROR (Status)) {
      if (Status == EFI_DEVICE_ERROR) {
        DEBUG ((
          DEBUG_ERROR,
          "%a: Label=\"%s\" ParentNodeId=%Lu Name=\"%a\" "
          "Errno=%d\n",
          __FUNCTION__,
          VirtioFs->Label,
          ParentNodeId,
          Name,
          CommonResp.Error
          ));
        Status = VirtioFsErrnoToEfiStatus (CommonResp.Error);
      }
  
      return Status;
    }
  
    //
    // Output the NodeId of the new directory.
    //
    *NodeId = NodeResp.NodeId;
    return EFI_SUCCESS;
  }
  