OvmfPkg/VirtioFsDxe: convert FUSE dirent filename to EFI_FILE_INFO

[mirror_edk2.git] / OvmfPkg / VirtioFsDxe / SimpleFsDelete.c

/** @file\r
  EFI_FILE_PROTOCOL.Delete() member function for the Virtio Filesystem driver.\r
\r
  Copyright (C) 2020, Red Hat, Inc.\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
**/\r
\r
#include <Library/BaseLib.h>             // RemoveEntryList()\r
#include <Library/MemoryAllocationLib.h> // FreePool()\r
\r
#include "VirtioFsDxe.h"\r
\r
EFI_STATUS\r
EFIAPI\r
VirtioFsSimpleFileDelete (\r
  IN EFI_FILE_PROTOCOL *This\r
  )\r
{\r
  VIRTIO_FS_FILE *VirtioFsFile;\r
  VIRTIO_FS      *VirtioFs;\r
  EFI_STATUS     Status;\r
\r
  VirtioFsFile = VIRTIO_FS_FILE_FROM_SIMPLE_FILE (This);\r
  VirtioFs     = VirtioFsFile->OwnerFs;\r
\r
  //\r
  // All actions in this function are "best effort"; the UEFI spec requires\r
  // EFI_FILE_PROTOCOL.Delete() to release resources unconditionally. If a step\r
  // related to removing the file fails, it's only reflected in the return\r
  // status (EFI_WARN_DELETE_FAILURE rather than EFI_SUCCESS).\r
  //\r
  // Release, remove, and (if needed) forget. We don't waste time flushing and\r
  // syncing; if the EFI_FILE_PROTOCOL user cares enough, they should keep the\r
  // parent directory open until after this function call returns, and then\r
  // force a sync on *that* EFI_FILE_PROTOCOL instance, using either the\r
  // Flush() member function, or the Close() member function.\r
  //\r
  // If any action fails below, we still try the others.\r
  //\r
  VirtioFsFuseReleaseFileOrDir (VirtioFs, VirtioFsFile->NodeId,\r
    VirtioFsFile->FuseHandle, VirtioFsFile->IsDirectory);\r
\r
  //\r
  // VirtioFsFile->FuseHandle is gone at this point, but VirtioFsFile->NodeId\r
  // is still valid. Continue with removing the file or directory. The result\r
  // of this operation determines the return status of the function.\r
  //\r
  if (VirtioFsFile->IsOpenForWriting) {\r
    UINT64 ParentNodeId;\r
    CHAR8  *LastComponent;\r
\r
    //\r
    // Split our canonical pathname into most specific parent directory\r
    // (identified by NodeId), and single-component filename within that\r
    // directory. If This stands for the root directory "/", then the following\r
    // function call will gracefully fail.\r
    //\r
    Status = VirtioFsLookupMostSpecificParentDir (\r
               VirtioFs,\r
               VirtioFsFile->CanonicalPathname,\r
               &ParentNodeId,\r
               &LastComponent\r
               );\r
    if (!EFI_ERROR (Status)) {\r
      //\r
      // Attempt the actual removal. Regardless of the outcome, ParentNodeId\r
      // must be forgotten right after (unless it stands for the root\r
      // directory).\r
      //\r
      Status = VirtioFsFuseRemoveFileOrDir (\r
                 VirtioFs,\r
                 ParentNodeId,\r
                 LastComponent,\r
                 VirtioFsFile->IsDirectory\r
                 );\r
      if (ParentNodeId != VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID) {\r
        VirtioFsFuseForget (VirtioFs, ParentNodeId);\r
      }\r
    }\r
    if (EFI_ERROR (Status)) {\r
      //\r
      // Map any failure to the spec-mandated warning code.\r
      //\r
      Status = EFI_WARN_DELETE_FAILURE;\r
    }\r
  } else {\r
    Status = EFI_WARN_DELETE_FAILURE;\r
  }\r
\r
  //\r
  // Finally, if we've known VirtioFsFile->NodeId from a lookup, then we should\r
  // also ask the server to forget it *once*.\r
  //\r
  if (VirtioFsFile->NodeId != VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID) {\r
    VirtioFsFuseForget (VirtioFs, VirtioFsFile->NodeId);\r
  }\r
\r
  //\r
  // One fewer file left open for the owner filesystem.\r
  //\r
  RemoveEntryList (&VirtioFsFile->OpenFilesEntry);\r
\r
  FreePool (VirtioFsFile->CanonicalPathname);\r
  FreePool (VirtioFsFile);\r
  return Status;\r
}\r