audk/OvmfPkg/Include/IndustryStandard/VirtioFs.h

455 lines
12 KiB
C

/** @file
Type and macro definitions specific to the Virtio Filesystem device.
At the time of this writing, the latest released Virtio specification (v1.1)
does not include the virtio-fs device. The development version of the
specification defines it however; see the latest version at
<https://github.com/oasis-tcs/virtio-spec/blob/87fa6b5d8155/virtio-fs.tex>.
This header file is minimal, and only defines the types and macros that are
necessary for the OvmfPkg implementation.
Copyright (C) 2020, Red Hat, Inc.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef VIRTIO_FS_H_
#define VIRTIO_FS_H_
#include <IndustryStandard/Virtio.h>
//
// Lowest numbered queue for sending normal priority requests.
//
#define VIRTIO_FS_REQUEST_QUEUE 1
//
// Number of bytes in the "VIRTIO_FS_CONFIG.Tag" field.
//
#define VIRTIO_FS_TAG_BYTES 36
//
// Device configuration layout.
//
#pragma pack (1)
typedef struct {
//
// The Tag field can be considered the filesystem label, or a mount point
// hint. It is UTF-8 encoded, and padded to full size with NUL bytes. If the
// encoded bytes take up the entire Tag field, then there is no NUL
// terminator.
//
UINT8 Tag[VIRTIO_FS_TAG_BYTES];
//
// The total number of request virtqueues exposed by the device (i.e.,
// excluding the "hiprio" queue).
//
UINT32 NumReqQueues;
} VIRTIO_FS_CONFIG;
#pragma pack ()
//
// FUSE-related definitions follow.
//
// From virtio-v1.1-cs01-87fa6b5d8155, 5.11 File System Device: "[...] The
// driver acts as the FUSE client mounting the file system. The virtio file
// system device provides the mechanism for transporting FUSE requests [...]"
//
// Unfortunately, the documentation of the FUSE wire protocol is lacking. The
// Virtio spec (as of this writing) simply defers to
// "include/uapi/linux/fuse.h" in the Linux kernel source -- see the reference
// in virtio spec file "introduction.tex", at commit 87fa6b5d8155.
//
// Of course, "include/uapi/linux/fuse.h" is a moving target (the virtio spec
// does not specify a particular FUSE interface version). The OvmfPkg code
// targets version 7.31, because that's the lowest version that the QEMU
// virtio-fs daemon supports at this time -- see QEMU commit 72c42e2d6551
// ("virtiofsd: Trim out compatibility code", 2020-01-23).
//
// Correspondingly, Linux's "include/uapi/linux/fuse.h" is consulted as checked
// out at commit (c6ff213fe5b8^) = d78092e4937d ("fuse: fix page dereference
// after free", 2020-09-18); that is, right before commit c6ff213fe5b8 ("fuse:
// add submount support to <uapi/linux/fuse.h>", 2020-09-18) introduces FUSE
// interface version 7.32.
//
#define VIRTIO_FS_FUSE_MAJOR 7
#define VIRTIO_FS_FUSE_MINOR 31
//
// The inode number of the root directory.
//
#define VIRTIO_FS_FUSE_ROOT_DIR_NODE_ID 1
//
// Distinguished errno values.
//
#define VIRTIO_FS_FUSE_ERRNO_ENOENT (-2)
//
// File mode bitmasks.
//
#define VIRTIO_FS_FUSE_MODE_TYPE_MASK 0170000u
#define VIRTIO_FS_FUSE_MODE_TYPE_REG 0100000u
#define VIRTIO_FS_FUSE_MODE_TYPE_DIR 0040000u
#define VIRTIO_FS_FUSE_MODE_PERM_RWXU 0000700u
#define VIRTIO_FS_FUSE_MODE_PERM_RUSR 0000400u
#define VIRTIO_FS_FUSE_MODE_PERM_WUSR 0000200u
#define VIRTIO_FS_FUSE_MODE_PERM_XUSR 0000100u
#define VIRTIO_FS_FUSE_MODE_PERM_RWXG 0000070u
#define VIRTIO_FS_FUSE_MODE_PERM_RGRP 0000040u
#define VIRTIO_FS_FUSE_MODE_PERM_WGRP 0000020u
#define VIRTIO_FS_FUSE_MODE_PERM_XGRP 0000010u
#define VIRTIO_FS_FUSE_MODE_PERM_RWXO 0000007u
#define VIRTIO_FS_FUSE_MODE_PERM_ROTH 0000004u
#define VIRTIO_FS_FUSE_MODE_PERM_WOTH 0000002u
#define VIRTIO_FS_FUSE_MODE_PERM_XOTH 0000001u
//
// Flags for VirtioFsFuseOpSetAttr, in the VIRTIO_FS_FUSE_SETATTR_REQUEST.Valid
// field.
//
#define VIRTIO_FS_FUSE_SETATTR_REQ_F_MODE BIT0
#define VIRTIO_FS_FUSE_SETATTR_REQ_F_SIZE BIT3
#define VIRTIO_FS_FUSE_SETATTR_REQ_F_ATIME BIT4
#define VIRTIO_FS_FUSE_SETATTR_REQ_F_MTIME BIT5
//
// Flags for VirtioFsFuseOpOpen.
//
#define VIRTIO_FS_FUSE_OPEN_REQ_F_RDONLY 0
#define VIRTIO_FS_FUSE_OPEN_REQ_F_RDWR 2
//
// Flags for VirtioFsFuseOpInit.
//
#define VIRTIO_FS_FUSE_INIT_REQ_F_DO_READDIRPLUS BIT13
/**
Macro for calculating the size of a directory stream entry.
The macro may evaluate Namelen multiple times.
The macro evaluates to a UINTN value that is safe to cast to UINT32.
@param[in] Namelen The size of the filename byte array that follows
VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE in the directory
stream, as reported by
VIRTIO_FS_FUSE_STATFS_RESPONSE.Namelen or
VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE.Namelen. The filename
byte array is not NUL-terminated.
@retval 0 Namelen was zero or greater than SIZE_4KB.
@return The number of bytes in the directory entry, including the
VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE header.
**/
#define VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE_SIZE(Namelen) \
((Namelen) == 0 || (Namelen) > SIZE_4KB ? \
(UINTN)0 : \
ALIGN_VALUE ( \
sizeof (VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE) + (UINTN)(Namelen), \
sizeof (UINT64) \
) \
)
//
// Flags for VirtioFsFuseOpRename2.
//
#define VIRTIO_FS_FUSE_RENAME2_REQ_F_NOREPLACE BIT0
//
// FUSE operation codes.
//
typedef enum {
VirtioFsFuseOpLookup = 1,
VirtioFsFuseOpForget = 2,
VirtioFsFuseOpGetAttr = 3,
VirtioFsFuseOpSetAttr = 4,
VirtioFsFuseOpMkDir = 9,
VirtioFsFuseOpUnlink = 10,
VirtioFsFuseOpRmDir = 11,
VirtioFsFuseOpOpen = 14,
VirtioFsFuseOpRead = 15,
VirtioFsFuseOpWrite = 16,
VirtioFsFuseOpStatFs = 17,
VirtioFsFuseOpRelease = 18,
VirtioFsFuseOpFsync = 20,
VirtioFsFuseOpFlush = 25,
VirtioFsFuseOpInit = 26,
VirtioFsFuseOpOpenDir = 27,
VirtioFsFuseOpReleaseDir = 29,
VirtioFsFuseOpFsyncDir = 30,
VirtioFsFuseOpCreate = 35,
VirtioFsFuseOpReadDirPlus = 44,
VirtioFsFuseOpRename2 = 45,
} VIRTIO_FS_FUSE_OPCODE;
#pragma pack (1)
//
// Request-response headers common to all request types.
//
typedef struct {
UINT32 Len;
UINT32 Opcode;
UINT64 Unique;
UINT64 NodeId;
UINT32 Uid;
UINT32 Gid;
UINT32 Pid;
UINT32 Padding;
} VIRTIO_FS_FUSE_REQUEST;
typedef struct {
UINT32 Len;
INT32 Error;
UINT64 Unique;
} VIRTIO_FS_FUSE_RESPONSE;
//
// Structure with which the Virtio Filesystem device reports a NodeId to the
// FUSE client (i.e., to the Virtio Filesystem driver). This structure is a
// part of the response headers for operations that inform the FUSE client of
// an inode.
//
typedef struct {
UINT64 NodeId;
UINT64 Generation;
UINT64 EntryValid;
UINT64 AttrValid;
UINT32 EntryValidNsec;
UINT32 AttrValidNsec;
} VIRTIO_FS_FUSE_NODE_RESPONSE;
//
// Structure describing the host-side attributes of an inode. This structure is
// a part of the response headers for operations that inform the FUSE client of
// an inode.
//
typedef struct {
UINT64 Ino;
UINT64 Size;
UINT64 Blocks;
UINT64 Atime;
UINT64 Mtime;
UINT64 Ctime;
UINT32 AtimeNsec;
UINT32 MtimeNsec;
UINT32 CtimeNsec;
UINT32 Mode;
UINT32 Nlink;
UINT32 Uid;
UINT32 Gid;
UINT32 Rdev;
UINT32 Blksize;
UINT32 Padding;
} VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE;
//
// Header for VirtioFsFuseOpForget.
//
typedef struct {
UINT64 NumberOfLookups;
} VIRTIO_FS_FUSE_FORGET_REQUEST;
//
// Headers for VirtioFsFuseOpGetAttr (VIRTIO_FS_FUSE_GETATTR_RESPONSE is also
// for VirtioFsFuseOpSetAttr).
//
typedef struct {
UINT32 GetAttrFlags;
UINT32 Dummy;
UINT64 FileHandle;
} VIRTIO_FS_FUSE_GETATTR_REQUEST;
typedef struct {
UINT64 AttrValid;
UINT32 AttrValidNsec;
UINT32 Dummy;
} VIRTIO_FS_FUSE_GETATTR_RESPONSE;
//
// Header for VirtioFsFuseOpSetAttr.
//
typedef struct {
UINT32 Valid;
UINT32 Padding;
UINT64 FileHandle;
UINT64 Size;
UINT64 LockOwner;
UINT64 Atime;
UINT64 Mtime;
UINT64 Ctime;
UINT32 AtimeNsec;
UINT32 MtimeNsec;
UINT32 CtimeNsec;
UINT32 Mode;
UINT32 Unused4;
UINT32 Uid;
UINT32 Gid;
UINT32 Unused5;
} VIRTIO_FS_FUSE_SETATTR_REQUEST;
//
// Header for VirtioFsFuseOpMkDir.
//
typedef struct {
UINT32 Mode;
UINT32 Umask;
} VIRTIO_FS_FUSE_MKDIR_REQUEST;
//
// Headers for VirtioFsFuseOpOpen and VirtioFsFuseOpOpenDir.
//
typedef struct {
UINT32 Flags;
UINT32 Unused;
} VIRTIO_FS_FUSE_OPEN_REQUEST;
typedef struct {
UINT64 FileHandle;
UINT32 OpenFlags;
UINT32 Padding;
} VIRTIO_FS_FUSE_OPEN_RESPONSE;
//
// Header for VirtioFsFuseOpRead and VirtioFsFuseOpReadDirPlus.
//
typedef struct {
UINT64 FileHandle;
UINT64 Offset;
UINT32 Size;
UINT32 ReadFlags;
UINT64 LockOwner;
UINT32 Flags;
UINT32 Padding;
} VIRTIO_FS_FUSE_READ_REQUEST;
//
// Headers for VirtioFsFuseOpWrite.
//
typedef struct {
UINT64 FileHandle;
UINT64 Offset;
UINT32 Size;
UINT32 WriteFlags;
UINT64 LockOwner;
UINT32 Flags;
UINT32 Padding;
} VIRTIO_FS_FUSE_WRITE_REQUEST;
typedef struct {
UINT32 Size;
UINT32 Padding;
} VIRTIO_FS_FUSE_WRITE_RESPONSE;
//
// Header for VirtioFsFuseOpStatFs.
//
typedef struct {
UINT64 Blocks;
UINT64 Bfree;
UINT64 Bavail;
UINT64 Files;
UINT64 Ffree;
UINT32 Bsize;
UINT32 Namelen;
UINT32 Frsize;
UINT32 Padding;
UINT32 Spare[6];
} VIRTIO_FS_FUSE_STATFS_RESPONSE;
//
// Header for VirtioFsFuseOpRelease and VirtioFsFuseOpReleaseDir.
//
typedef struct {
UINT64 FileHandle;
UINT32 Flags;
UINT32 ReleaseFlags;
UINT64 LockOwner;
} VIRTIO_FS_FUSE_RELEASE_REQUEST;
//
// Header for VirtioFsFuseOpFsync and VirtioFsFuseOpFsyncDir.
//
typedef struct {
UINT64 FileHandle;
UINT32 FsyncFlags;
UINT32 Padding;
} VIRTIO_FS_FUSE_FSYNC_REQUEST;
//
// Header for VirtioFsFuseOpFlush.
//
typedef struct {
UINT64 FileHandle;
UINT32 Unused;
UINT32 Padding;
UINT64 LockOwner;
} VIRTIO_FS_FUSE_FLUSH_REQUEST;
//
// Headers for VirtioFsFuseOpInit.
//
typedef struct {
UINT32 Major;
UINT32 Minor;
UINT32 MaxReadahead;
UINT32 Flags;
} VIRTIO_FS_FUSE_INIT_REQUEST;
typedef struct {
UINT32 Major;
UINT32 Minor;
UINT32 MaxReadahead;
UINT32 Flags;
UINT16 MaxBackground;
UINT16 CongestionThreshold;
UINT32 MaxWrite;
UINT32 TimeGran;
UINT16 MaxPages;
UINT16 MapAlignment;
UINT32 Unused[8];
} VIRTIO_FS_FUSE_INIT_RESPONSE;
//
// Header for VirtioFsFuseOpCreate.
//
typedef struct {
UINT32 Flags;
UINT32 Mode;
UINT32 Umask;
UINT32 Padding;
} VIRTIO_FS_FUSE_CREATE_REQUEST;
//
// Header for VirtioFsFuseOpReadDirPlus.
//
// Diverging from the rest of the headers, this structure embeds other
// structures. The reason is that a scatter list cannot be used to receive
// NodeResp and AttrResp separately; the record below is followed by a variable
// size filename byte array, and then such pairs are repeated a number of
// times. Thus, later header start offsets depend on earlier filename array
// sizes.
//
typedef struct {
VIRTIO_FS_FUSE_NODE_RESPONSE NodeResp;
VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE AttrResp;
UINT64 NodeId;
UINT64 CookieForNextEntry;
UINT32 Namelen;
UINT32 Type;
} VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE;
//
// Header for VirtioFsFuseOpRename2.
//
typedef struct {
UINT64 NewDir;
UINT32 Flags;
UINT32 Padding;
} VIRTIO_FS_FUSE_RENAME2_REQUEST;
#pragma pack ()
#endif // VIRTIO_FS_H_