OvmfPkg/VirtioFsDxe/VirtioFsDxe.h

   1 /** @file
   2   Internal macro definitions, type definitions, and function declarations for
   3   the Virtio Filesystem device driver.
   4
   5   Copyright (C) 2020, Red Hat, Inc.
   6
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8 **/
   9
  10 #ifndef VIRTIO_FS_DXE_H_
  11 #define VIRTIO_FS_DXE_H_
  12
  13 #include <Base.h>                      // SIGNATURE_64()
  14 #include <IndustryStandard/VirtioFs.h> // VIRTIO_FS_TAG_BYTES
  15 #include <Library/DebugLib.h>          // CR()
  16 #include <Protocol/SimpleFileSystem.h> // EFI_SIMPLE_FILE_SYSTEM_PROTOCOL
  17 #include <Protocol/VirtioDevice.h>     // VIRTIO_DEVICE_PROTOCOL
  18 #include <Uefi/UefiBaseType.h>         // EFI_EVENT
  19
  20 #define VIRTIO_FS_SIG SIGNATURE_64 ('V', 'I', 'R', 'T', 'I', 'O', 'F', 'S')
  21
  22 //
  23 // Filesystem label encoded in UCS-2, transformed from the UTF-8 representation
  24 // in "VIRTIO_FS_CONFIG.Tag", and NUL-terminated. Only the printable ASCII code
  25 // points (U+0020 through U+007E) are supported.
  26 //
  27 typedef CHAR16 VIRTIO_FS_LABEL[VIRTIO_FS_TAG_BYTES + 1];
  28
  29 //
  30 // Main context structure, expressing an EFI_SIMPLE_FILE_SYSTEM_PROTOCOL
  31 // interface on top of the Virtio Filesystem device.
  32 //
  33 typedef struct {
  34   //
  35   // Parts of this structure are initialized / torn down in various functions
  36   // at various call depths. The table to the right should make it easier to
  37   // track them.
  38   //
  39   //                              field         init function       init depth
  40   //                              -----------   ------------------  ----------
  41   UINT64                          Signature; // DriverBindingStart  0
  42   VIRTIO_DEVICE_PROTOCOL          *Virtio;   // DriverBindingStart  0
  43   VIRTIO_FS_LABEL                 Label;     // VirtioFsInit        1
  44   UINT16                          QueueSize; // VirtioFsInit        1
  45   VRING                           Ring;      // VirtioRingInit      2
  46   VOID                            *RingMap;  // VirtioRingMap       2
  47   UINT64                          RequestId; // FuseInitSession     1
  48   EFI_EVENT                       ExitBoot;  // DriverBindingStart  0
  49   EFI_SIMPLE_FILE_SYSTEM_PROTOCOL SimpleFs;  // DriverBindingStart  0
  50 } VIRTIO_FS;
  51
  52 #define VIRTIO_FS_FROM_SIMPLE_FS(SimpleFsReference) \
  53   CR (SimpleFsReference, VIRTIO_FS, SimpleFs, VIRTIO_FS_SIG);
  54
  55 //
  56 // Structure for describing a contiguous buffer, potentially mapped for Virtio
  57 // transfer.
  58 //
  59 typedef struct {
  60   //
  61   // The following fields originate from the owner of the buffer.
  62   //
  63   VOID  *Buffer;
  64   UINTN Size;
  65   //
  66   // All of the fields below, until the end of the structure, are
  67   // zero-initialized when the structure is initially validated.
  68   //
  69   // Mapped, MappedAddress and Mapping are updated when the buffer is mapped
  70   // for VirtioOperationBusMasterRead or VirtioOperationBusMasterWrite. They
  71   // are again updated when the buffer is unmapped.
  72   //
  73   BOOLEAN              Mapped;
  74   EFI_PHYSICAL_ADDRESS MappedAddress;
  75   VOID                 *Mapping;
  76   //
  77   // Transferred is updated after VirtioFlush() returns successfully:
  78   // - for VirtioOperationBusMasterRead, Transferred is set to Size;
  79   // - for VirtioOperationBusMasterWrite, Transferred is calculated from the
  80   //   UsedLen output parameter of VirtioFlush().
  81   //
  82   UINTN Transferred;
  83 } VIRTIO_FS_IO_VECTOR;
  84
  85 //
  86 // Structure for describing a list of IO Vectors.
  87 //
  88 typedef struct {
  89   //
  90   // The following fields originate from the owner of the buffers.
  91   //
  92   VIRTIO_FS_IO_VECTOR *IoVec;
  93   UINTN               NumVec;
  94   //
  95   // TotalSize is calculated when the scatter-gather list is initially
  96   // validated.
  97   //
  98   UINT32 TotalSize;
  99 } VIRTIO_FS_SCATTER_GATHER_LIST;
 100
 101 //
 102 // Initialization and helper routines for the Virtio Filesystem device.
 103 //
 104
 105 EFI_STATUS
 106 VirtioFsInit (
 107   IN OUT VIRTIO_FS *VirtioFs
 108   );
 109
 110 VOID
 111 VirtioFsUninit (
 112   IN OUT VIRTIO_FS *VirtioFs
 113   );
 114
 115 VOID
 116 EFIAPI
 117 VirtioFsExitBoot (
 118   IN EFI_EVENT ExitBootEvent,
 119   IN VOID      *VirtioFsAsVoid
 120   );
 121
 122 EFI_STATUS
 123 VirtioFsSgListsValidate (
 124   IN     VIRTIO_FS                     *VirtioFs,
 125   IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *RequestSgList,
 126   IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *ResponseSgList OPTIONAL
 127   );
 128
 129 EFI_STATUS
 130 VirtioFsSgListsSubmit (
 131   IN OUT VIRTIO_FS                     *VirtioFs,
 132   IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *RequestSgList,
 133   IN OUT VIRTIO_FS_SCATTER_GATHER_LIST *ResponseSgList OPTIONAL
 134   );
 135
 136 EFI_STATUS
 137 VirtioFsFuseNewRequest (
 138   IN OUT VIRTIO_FS              *VirtioFs,
 139      OUT VIRTIO_FS_FUSE_REQUEST *Request,
 140   IN     UINT32                 RequestSize,
 141   IN     VIRTIO_FS_FUSE_OPCODE  Opcode,
 142   IN     UINT64                 NodeId
 143   );
 144
 145 EFI_STATUS
 146 VirtioFsFuseCheckResponse (
 147   IN  VIRTIO_FS_SCATTER_GATHER_LIST *ResponseSgList,
 148   IN  UINT64                        RequestId,
 149   OUT UINTN                         *TailBufferFill
 150   );
 151
 152 EFI_STATUS
 153 VirtioFsErrnoToEfiStatus (
 154   IN INT32 Errno
 155   );
 156
 157 //
 158 // Wrapper functions for FUSE commands (primitives).
 159 //
 160
 161 EFI_STATUS
 162 VirtioFsFuseInitSession (
 163   IN OUT VIRTIO_FS *VirtioFs
 164   );
 165
 166 //
 167 // EFI_SIMPLE_FILE_SYSTEM_PROTOCOL member functions for the Virtio Filesystem
 168 // driver.
 169 //
 170
 171 EFI_STATUS
 172 EFIAPI
 173 VirtioFsOpenVolume (
 174   IN  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *This,
 175   OUT EFI_FILE_PROTOCOL               **Root
 176   );
 177
 178 #endif // VIRTIO_FS_DXE_H_