OvmfPkg/VirtioFsDxe: manage path lifecycle in OpenVolume, Close, Delete

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

/** @file\r
  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL.OpenVolume() member function for the Virtio\r
  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>             // InsertTailList()\r
#include <Library/MemoryAllocationLib.h> // AllocatePool()\r
\r
#include "VirtioFsDxe.h"\r
\r
/**\r
  Open the root directory on the Virtio Filesystem.\r
\r
  Refer to EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_OPEN_VOLUME for the interface\r
  contract.\r
**/\r
EFI_STATUS\r
EFIAPI\r
VirtioFsOpenVolume (\r
  IN  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *This,\r
  OUT EFI_FILE_PROTOCOL               **Root\r
  )\r
{\r
  VIRTIO_FS      *VirtioFs;\r
  VIRTIO_FS_FILE *VirtioFsFile;\r
  EFI_STATUS     Status;\r
  CHAR8          *CanonicalPathname;\r
  UINT64         RootDirHandle;\r
\r
  VirtioFs = VIRTIO_FS_FROM_SIMPLE_FS (This);\r
\r
  VirtioFsFile = AllocatePool (sizeof *VirtioFsFile);\r
  if (VirtioFsFile == NULL) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  CanonicalPathname = AllocateCopyPool (sizeof "/", "/");\r
  if (CanonicalPathname == NULL) {\r
    Status = EFI_OUT_OF_RESOURCES;\r
    goto FreeVirtioFsFile;\r
  }\r
\r
  //\r
  // Open the root directory.\r
  //\r
  Status = VirtioFsFuseOpenDir (VirtioFs, VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID,\r
             &RootDirHandle);\r
  if (EFI_ERROR (Status)) {\r
    goto FreeCanonicalPathname;\r
  }\r
\r
  //\r
  // Populate the new VIRTIO_FS_FILE object.\r
  //\r
  VirtioFsFile->Signature              = VIRTIO_FS_FILE_SIG;\r
  VirtioFsFile->SimpleFile.Revision    = EFI_FILE_PROTOCOL_REVISION;\r
  VirtioFsFile->SimpleFile.Open        = VirtioFsSimpleFileOpen;\r
  VirtioFsFile->SimpleFile.Close       = VirtioFsSimpleFileClose;\r
  VirtioFsFile->SimpleFile.Delete      = VirtioFsSimpleFileDelete;\r
  VirtioFsFile->SimpleFile.Read        = VirtioFsSimpleFileRead;\r
  VirtioFsFile->SimpleFile.Write       = VirtioFsSimpleFileWrite;\r
  VirtioFsFile->SimpleFile.GetPosition = VirtioFsSimpleFileGetPosition;\r
  VirtioFsFile->SimpleFile.SetPosition = VirtioFsSimpleFileSetPosition;\r
  VirtioFsFile->SimpleFile.GetInfo     = VirtioFsSimpleFileGetInfo;\r
  VirtioFsFile->SimpleFile.SetInfo     = VirtioFsSimpleFileSetInfo;\r
  VirtioFsFile->SimpleFile.Flush       = VirtioFsSimpleFileFlush;\r
  VirtioFsFile->IsDirectory            = TRUE;\r
  VirtioFsFile->IsOpenForWriting       = FALSE;\r
  VirtioFsFile->OwnerFs                = VirtioFs;\r
  VirtioFsFile->CanonicalPathname      = CanonicalPathname;\r
  VirtioFsFile->NodeId                 = VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID;\r
  VirtioFsFile->FuseHandle             = RootDirHandle;\r
\r
  //\r
  // One more file open for the filesystem.\r
  //\r
  InsertTailList (&VirtioFs->OpenFiles, &VirtioFsFile->OpenFilesEntry);\r
\r
  *Root = &VirtioFsFile->SimpleFile;\r
  return EFI_SUCCESS;\r
\r
FreeCanonicalPathname:\r
  FreePool (CanonicalPathname);\r
\r
FreeVirtioFsFile:\r
  FreePool (VirtioFsFile);\r
\r
  return Status;\r
}\r