1 files changed, 163 insertions, 0 deletions
diff --git a/ArmPlatformPkg/FileSystem/BootMonFs/BootMonFsReadWrite.c b/ArmPlatformPkg/FileSystem/BootMonFs/BootMonFsReadWrite.c
new file mode 100644
index 0000000000..653b2c507c
--- /dev/null
+++ b/ArmPlatformPkg/FileSystem/BootMonFs/BootMonFsReadWrite.c
@@ -0,0 +1,163 @@
+/** @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"
+
+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
+    *BufferSize = 0;
+    return EFI_DEVICE_ERROR;
+  }
+
+  // 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;
+}