#define VIRTIO_FS_FUSE_OPEN_REQ_F_RDONLY 0\r
#define VIRTIO_FS_FUSE_OPEN_REQ_F_RDWR 2\r
\r
+//\r
+// Flags for VirtioFsFuseOpInit.\r
+//\r
+#define VIRTIO_FS_FUSE_INIT_REQ_F_DO_READDIRPLUS BIT13\r
+\r
+/**\r
+ Macro for calculating the size of a directory stream entry.\r
+\r
+ The macro may evaluate Namelen multiple times.\r
+\r
+ The macro evaluates to a UINTN value that is safe to cast to UINT32.\r
+\r
+ @param[in] Namelen The size of the filename byte array that follows\r
+ VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE in the directory\r
+ stream, as reported by\r
+ VIRTIO_FS_FUSE_STATFS_RESPONSE.Namelen or\r
+ VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE.Namelen. The filename\r
+ byte array is not NUL-terminated.\r
+\r
+ @retval 0 Namelen was zero or greater than SIZE_4KB.\r
+\r
+ @return The number of bytes in the directory entry, including the\r
+ VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE header.\r
+**/\r
+#define VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE_SIZE(Namelen) \\r
+ ((Namelen) == 0 || (Namelen) > SIZE_4KB ? \\r
+ (UINTN)0 : \\r
+ ALIGN_VALUE ( \\r
+ sizeof (VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE) + (UINTN)(Namelen), \\r
+ sizeof (UINT64) \\r
+ ) \\r
+ )\r
+\r
//\r
// FUSE operation codes.\r
//\r
VirtioFsFuseOpUnlink = 10,\r
VirtioFsFuseOpRmDir = 11,\r
VirtioFsFuseOpOpen = 14,\r
+ VirtioFsFuseOpRead = 15,\r
VirtioFsFuseOpStatFs = 17,\r
VirtioFsFuseOpRelease = 18,\r
VirtioFsFuseOpFsync = 20,\r
VirtioFsFuseOpReleaseDir = 29,\r
VirtioFsFuseOpFsyncDir = 30,\r
VirtioFsFuseOpCreate = 35,\r
+ VirtioFsFuseOpReadDirPlus = 44,\r
} VIRTIO_FS_FUSE_OPCODE;\r
\r
#pragma pack (1)\r
UINT32 Padding;\r
} VIRTIO_FS_FUSE_OPEN_RESPONSE;\r
\r
+//\r
+// Header for VirtioFsFuseOpRead and VirtioFsFuseOpReadDirPlus.\r
+//\r
+typedef struct {\r
+ UINT64 FileHandle;\r
+ UINT64 Offset;\r
+ UINT32 Size;\r
+ UINT32 ReadFlags;\r
+ UINT64 LockOwner;\r
+ UINT32 Flags;\r
+ UINT32 Padding;\r
+} VIRTIO_FS_FUSE_READ_REQUEST;\r
+\r
//\r
// Header for VirtioFsFuseOpStatFs.\r
//\r
UINT32 Umask;\r
UINT32 Padding;\r
} VIRTIO_FS_FUSE_CREATE_REQUEST;\r
+\r
+//\r
+// Header for VirtioFsFuseOpReadDirPlus.\r
+//\r
+// Diverging from the rest of the headers, this structure embeds other\r
+// structures. The reason is that a scatter list cannot be used to receive\r
+// NodeResp and AttrResp separately; the record below is followed by a variable\r
+// size filename byte array, and then such pairs are repeated a number of\r
+// times. Thus, later header start offsets depend on earlier filename array\r
+// sizes.\r
+//\r
+typedef struct {\r
+ VIRTIO_FS_FUSE_NODE_RESPONSE NodeResp;\r
+ VIRTIO_FS_FUSE_ATTRIBUTES_RESPONSE AttrResp;\r
+ UINT64 NodeId;\r
+ UINT64 CookieForNextEntry;\r
+ UINT32 Namelen;\r
+ UINT32 Type;\r
+} VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE;\r
#pragma pack ()\r
\r
#endif // VIRTIO_FS_H_\r
--- /dev/null
+/** @file\r
+ FUSE_READ / FUSE_READDIRPLUS wrapper for the Virtio Filesystem device.\r
+\r
+ Copyright (C) 2020, Red Hat, Inc.\r
+\r
+ SPDX-License-Identifier: BSD-2-Clause-Patent\r
+**/\r
+\r
+#include "VirtioFsDxe.h"\r
+\r
+/**\r
+ Read a chunk from a regular file or a directory stream, by sending the\r
+ FUSE_READ / FUSE_READDIRPLUS request to the Virtio Filesystem device.\r
+\r
+ The function may only be called after VirtioFsFuseInitSession() returns\r
+ successfully and before VirtioFsUninit() is called.\r
+\r
+ @param[in,out] VirtioFs The Virtio Filesystem device to send the FUSE_READ\r
+ or FUSE_READDIRPLUS request to. On output, the FUSE\r
+ request counter "VirtioFs->RequestId" will have been\r
+ incremented.\r
+\r
+ @param[in] NodeId The inode number of the regular file or directory\r
+ stream to read from.\r
+\r
+ @param[in] FuseHandle The open handle to the regular file or directory\r
+ stream to read from.\r
+\r
+ @param[in] IsDir TRUE if NodeId and FuseHandle refer to a directory,\r
+ FALSE if NodeId and FuseHandle refer to a regular\r
+ file.\r
+\r
+ @param[in] Offset If IsDir is FALSE: the absolute file position at\r
+ which to start reading.\r
+\r
+ If IsDir is TRUE: the directory stream cookie at\r
+ which to start or continue reading. The zero-valued\r
+ cookie identifies the start of the directory stream.\r
+ Further positions in the directory stream can be\r
+ passed in from the CookieForNextEntry field of\r
+ VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE.\r
+\r
+ @param[in,out] Size On input, the number of bytes to read. On successful\r
+ return, the number of bytes actually read, which may\r
+ be smaller than the value on input.\r
+\r
+ When reading a regular file (i.e., when IsDir is\r
+ FALSE), EOF can be detected by passing in a nonzero\r
+ Size, and finding a zero Size on output.\r
+\r
+ When reading a directory stream (i.e., when IsDir is\r
+ TRUE), Data consists of a sequence of variably-sized\r
+ records (directory entries). A read operation\r
+ returns the maximal sequence of records that fits in\r
+ Size, without having to truncate a record. In order\r
+ to guarantee progress, call\r
+\r
+ VirtioFsFuseStatFs (VirtioFs, NodeId,\r
+ &FilesysAttr)\r
+\r
+ first, to learn the maximum Namelen for the\r
+ directory stream. Then assign Size at least\r
+\r
+ VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE_SIZE (\r
+ FilesysAttr.Namelen)\r
+\r
+ on input. (Remember that\r
+ VIRTIO_FS_FUSE_DIRENTPLUS_RESPONSE_SIZE() may return\r
+ 0 if its Namelen argument is invalid.) EOF can be\r
+ detected if Size is set on input like described\r
+ above, and Size is zero on output.\r
+\r
+ @param[out] Data Buffer to read the bytes from the regular file or\r
+ the directory stream into. The caller is responsible\r
+ for providing room for (at least) as many bytes in\r
+ Data as Size is on input.\r
+\r
+ @retval EFI_SUCCESS Read successful. The caller is responsible for checking\r
+ Size to learn the actual byte count transferred.\r
+\r
+ @return The "errno" value mapped to an EFI_STATUS code, if the\r
+ Virtio Filesystem device explicitly reported an error.\r
+\r
+ @return Error codes propagated from VirtioFsSgListsValidate(),\r
+ VirtioFsFuseNewRequest(), VirtioFsSgListsSubmit(),\r
+ VirtioFsFuseCheckResponse().\r
+**/\r
+EFI_STATUS\r
+VirtioFsFuseReadFileOrDir (\r
+ IN OUT VIRTIO_FS *VirtioFs,\r
+ IN UINT64 NodeId,\r
+ IN UINT64 FuseHandle,\r
+ IN BOOLEAN IsDir,\r
+ IN UINT64 Offset,\r
+ IN OUT UINT32 *Size,\r
+ OUT VOID *Data\r
+ )\r
+{\r
+ VIRTIO_FS_FUSE_REQUEST CommonReq;\r
+ VIRTIO_FS_FUSE_READ_REQUEST ReadReq;\r
+ VIRTIO_FS_IO_VECTOR ReqIoVec[2];\r
+ VIRTIO_FS_SCATTER_GATHER_LIST ReqSgList;\r
+ VIRTIO_FS_FUSE_RESPONSE CommonResp;\r
+ VIRTIO_FS_IO_VECTOR RespIoVec[2];\r
+ VIRTIO_FS_SCATTER_GATHER_LIST RespSgList;\r
+ EFI_STATUS Status;\r
+ UINTN TailBufferFill;\r
+\r
+ //\r
+ // Set up the scatter-gather lists.\r
+ //\r
+ ReqIoVec[0].Buffer = &CommonReq;\r
+ ReqIoVec[0].Size = sizeof CommonReq;\r
+ ReqIoVec[1].Buffer = &ReadReq;\r
+ ReqIoVec[1].Size = sizeof ReadReq;\r
+ ReqSgList.IoVec = ReqIoVec;\r
+ ReqSgList.NumVec = ARRAY_SIZE (ReqIoVec);\r
+\r
+ RespIoVec[0].Buffer = &CommonResp;\r
+ RespIoVec[0].Size = sizeof CommonResp;\r
+ RespIoVec[1].Buffer = Data;\r
+ RespIoVec[1].Size = *Size;\r
+ RespSgList.IoVec = RespIoVec;\r
+ RespSgList.NumVec = ARRAY_SIZE (RespIoVec);\r
+\r
+ //\r
+ // Validate the scatter-gather lists; calculate the total transfer sizes.\r
+ //\r
+ Status = VirtioFsSgListsValidate (VirtioFs, &ReqSgList, &RespSgList);\r
+ if (EFI_ERROR (Status)) {\r
+ return Status;\r
+ }\r
+\r
+ //\r
+ // Populate the common request header.\r
+ //\r
+ Status = VirtioFsFuseNewRequest (\r
+ VirtioFs,\r
+ &CommonReq,\r
+ ReqSgList.TotalSize,\r
+ IsDir ? VirtioFsFuseOpReadDirPlus : VirtioFsFuseOpRead,\r
+ NodeId\r
+ );\r
+ if (EFI_ERROR (Status)) {\r
+ return Status;\r
+ }\r
+\r
+ //\r
+ // Populate the FUSE_READ- / FUSE_READDIRPLUS-specific fields.\r
+ //\r
+ ReadReq.FileHandle = FuseHandle;\r
+ ReadReq.Offset = Offset;\r
+ ReadReq.Size = *Size;\r
+ ReadReq.ReadFlags = 0;\r
+ ReadReq.LockOwner = 0;\r
+ ReadReq.Flags = 0;\r
+ ReadReq.Padding = 0;\r
+\r
+ //\r
+ // Submit the request.\r
+ //\r
+ Status = VirtioFsSgListsSubmit (VirtioFs, &ReqSgList, &RespSgList);\r
+ if (EFI_ERROR (Status)) {\r
+ return Status;\r
+ }\r
+\r
+ //\r
+ // Verify the response. Note that TailBufferFill is variable.\r
+ //\r
+ Status = VirtioFsFuseCheckResponse (&RespSgList, CommonReq.Unique,\r
+ &TailBufferFill);\r
+ if (EFI_ERROR (Status)) {\r
+ if (Status == EFI_DEVICE_ERROR) {\r
+ DEBUG ((DEBUG_ERROR, "%a: Label=\"%s\" NodeId=%Lu FuseHandle=%Lu "\r
+ "IsDir=%d Offset=0x%Lx Size=0x%x Data@%p Errno=%d\n", __FUNCTION__,\r
+ VirtioFs->Label, NodeId, FuseHandle, IsDir, Offset, *Size, Data,\r
+ CommonResp.Error));\r
+ Status = VirtioFsErrnoToEfiStatus (CommonResp.Error);\r
+ }\r
+ return Status;\r
+ }\r
+\r
+ //\r
+ // Report the actual transfer size.\r
+ //\r
+ // Integer overflow in the (UINT32) cast below is not possible; the\r
+ // VIRTIO_FS_SCATTER_GATHER_LIST functions would have caught that.\r
+ //\r
+ *Size = (UINT32)TailBufferFill;\r
+ return EFI_SUCCESS;\r
+}\r
projects / mirror_edk2.git / commitdiff