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/** @file
*
* Copyright (c) 2012-2014, ARM Limited. All rights reserved.
*
* This program and the accompanying materials
* are licensed and made available under the terms and conditions of the BSD License
* which accompanies this distribution. The full text of the license may be found at
* http://opensource.org/licenses/bsd-license.php
*
* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
*
**/
#include <Protocol/SimpleFileSystem.h>
#include <Library/UefiLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/DebugLib.h>
#include "BootMonFsInternal.h"
/**
Read data from an open file.
@param[in] This A pointer to the EFI_FILE_PROTOCOL instance that
is the file handle to read data from.
@param[in out] BufferSize On input, the size of the Buffer. On output, the
amount of data returned in Buffer. In both cases,
the size is measured in bytes.
@param[out] Buffer The buffer into which the data is read.
@retval EFI_SUCCESS The data was read.
@retval EFI_DEVICE_ERROR On entry, the current file position is
beyond the end of the file, or the device
reported an error while performing the read
operation.
@retval EFI_INVALID_PARAMETER At least one of the parameters is invalid.
**/
EFIAPI
EFI_STATUS
BootMonFsReadFile (
IN EFI_FILE_PROTOCOL *This,
IN OUT UINTN *BufferSize,
OUT VOID *Buffer
)
{
BOOTMON_FS_INSTANCE *Instance;
BOOTMON_FS_FILE *File;
EFI_DISK_IO_PROTOCOL *DiskIo;
EFI_BLOCK_IO_MEDIA *Media;
UINT64 FileStart;
EFI_STATUS Status;
UINTN RemainingFileSize;
// Ensure the file has been written in Flash before reading it.
// This keeps the code simple and avoids having to manage a non-flushed file.
BootMonFsFlushFile (This);
File = BOOTMON_FS_FILE_FROM_FILE_THIS (This);
if (File == NULL) {
return EFI_INVALID_PARAMETER;
}
Instance = File->Instance;
DiskIo = Instance->DiskIo;
Media = Instance->Media;
FileStart = (Media->LowestAlignedLba + File->HwDescription.BlockStart) * Media->BlockSize;
if (File->Position >= File->HwDescription.Region[0].Size) {
// The entire file has been read or the position has been
// set past the end of the file.
*BufferSize = 0;
if (File->Position > File->HwDescription.Region[0].Size) {
return EFI_DEVICE_ERROR;
} else {
return EFI_SUCCESS;
}
}
// This driver assumes that the entire file is in region 0.
RemainingFileSize = File->HwDescription.Region[0].Size - File->Position;
// If read would go past end of file, truncate the read
if (*BufferSize > RemainingFileSize) {
*BufferSize = RemainingFileSize;
}
Status = DiskIo->ReadDisk (
DiskIo,
Media->MediaId,
FileStart + File->Position,
*BufferSize,
Buffer
);
if (EFI_ERROR (Status)) {
*BufferSize = 0;
}
File->Position += *BufferSize;
return Status;
}
// Inserts an entry into the write chain
EFIAPI
EFI_STATUS
BootMonFsWriteFile (
IN EFI_FILE_PROTOCOL *This,
IN OUT UINTN *BufferSize,
IN VOID *Buffer
)
{
BOOTMON_FS_FILE *File;
BOOTMON_FS_FILE_REGION *Region;
File = BOOTMON_FS_FILE_FROM_FILE_THIS (This);
if (File == NULL) {
return EFI_INVALID_PARAMETER;
}
if (!(File->OpenMode & EFI_FILE_MODE_WRITE)) {
return EFI_ACCESS_DENIED;
}
// Allocate and initialize the memory region
Region = (BOOTMON_FS_FILE_REGION*)AllocateZeroPool (sizeof (BOOTMON_FS_FILE_REGION));
if (Region == NULL) {
return EFI_OUT_OF_RESOURCES;
}
Region->Buffer = AllocateCopyPool (*BufferSize, Buffer);
if (Region->Buffer == NULL) {
FreePool (Region);
return EFI_OUT_OF_RESOURCES;
}
Region->Size = *BufferSize;
Region->Offset = File->Position;
InsertTailList (&File->RegionToFlushLink, &Region->Link);
File->Position += *BufferSize;
return EFI_SUCCESS;
}
EFIAPI
EFI_STATUS
BootMonFsSetPosition (
IN EFI_FILE_PROTOCOL *This,
IN UINT64 Position
)
{
BOOTMON_FS_FILE *File;
File = BOOTMON_FS_FILE_FROM_FILE_THIS (This);
// UEFI Spec section 12.5:
// "Seeking to position 0xFFFFFFFFFFFFFFFF causes the current position to
// be set to the end of the file."
if (Position == 0xFFFFFFFFFFFFFFFF) {
File->Position = BootMonFsGetImageLength (File);
} else {
// NB: Seeking past the end of the file is valid.
File->Position = Position;
}
return EFI_SUCCESS;
}
EFIAPI
EFI_STATUS
BootMonFsGetPosition (
IN EFI_FILE_PROTOCOL *This,
OUT UINT64 *Position
) {
BOOTMON_FS_FILE *File;
File = BOOTMON_FS_FILE_FROM_FILE_THIS (This);
*Position = File->Position;
return EFI_SUCCESS;
}
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