[PATCH v2 03/14] arm64: efi: move EFI header and related data to a separate .S file

Ard Biesheuvel
2017-02-08T11:55:36Z

In preparation of yet another round of modifications to the PE/COFF
header, macroize it and move the definition into a separate source
file.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
arch/arm64/kernel/efi-header.S | 158 ++++++++++++++++++++
arch/arm64/kernel/head.S | 150 +------------------
2 files changed, 161 insertions(+), 147 deletions(-)

diff --git a/arch/arm64/kernel/efi-header.S b/arch/arm64/kernel/efi-header.S
new file mode 100644
index 000000000000..9b24ce130afb
--- /dev/null
+++ b/arch/arm64/kernel/efi-header.S
@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2013 - 2017 Linaro, Ltd.
+ * Copyright (C) 2013, 2014 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+ .macro __EFI_PE_HEADER
+ .ascii "PE"
+ .short 0
+coff_header:
+ .short 0xaa64 // AArch64
+ .short 2 // nr_sections
+ .long 0 // TimeDateStamp
+ .long 0 // PointerToSymbolTable
+ .long 1 // NumberOfSymbols
+ .short section_table - optional_header // SizeOfOptionalHeader
+ .short 0x206 // Characteristics.
+ // IMAGE_FILE_DEBUG_STRIPPED |
+ // IMAGE_FILE_EXECUTABLE_IMAGE |
+ // IMAGE_FILE_LINE_NUMS_STRIPPED
+optional_header:
+ .short 0x20b // PE32+ format
+ .byte 0x02 // MajorLinkerVersion
+ .byte 0x14 // MinorLinkerVersion
+ .long _end - efi_header_end // SizeOfCode
+ .long 0 // SizeOfInitializedData
+ .long 0 // SizeOfUninitializedData
+ .long __efistub_entry - _head // AddressOfEntryPoint
+ .long efi_header_end - _head // BaseOfCode
+
+extra_header_fields:
+ .quad 0 // ImageBase
+ .long 0x1000 // SectionAlignment
+ .long PECOFF_FILE_ALIGNMENT // FileAlignment
+ .short 0 // MajorOperatingSystemVersion
+ .short 0 // MinorOperatingSystemVersion
+ .short 0 // MajorImageVersion
+ .short 0 // MinorImageVersion
+ .short 0 // MajorSubsystemVersion
+ .short 0 // MinorSubsystemVersion
+ .long 0 // Win32VersionValue
+
+ .long _end - _head // SizeOfImage
+
+ // Everything before the kernel image is considered part of the header
+ .long efi_header_end - _head // SizeOfHeaders
+ .long 0 // CheckSum
+ .short 0xa // Subsystem (EFI application)
+ .short 0 // DllCharacteristics
+ .quad 0 // SizeOfStackReserve
+ .quad 0 // SizeOfStackCommit
+ .quad 0 // SizeOfHeapReserve
+ .quad 0 // SizeOfHeapCommit
+ .long 0 // LoaderFlags
+ .long (section_table - .) / 8 // NumberOfRvaAndSizes
+
+ .quad 0 // ExportTable
+ .quad 0 // ImportTable
+ .quad 0 // ResourceTable
+ .quad 0 // ExceptionTable
+ .quad 0 // CertificationTable
+ .quad 0 // BaseRelocationTable
+
+#ifdef CONFIG_DEBUG_EFI
+ .long efi_debug_table - _head // DebugTable
+ .long efi_debug_table_size
+#endif
+
+ // Section table
+section_table:
+
+ /*
+ * The EFI application loader requires a relocation section
+ * because EFI applications must be relocatable. This is a
+ * dummy section as far as we are concerned.
+ */
+ .ascii ".reloc"
+ .byte 0
+ .byte 0 // end of 0 padding of section name
+ .long 0
+ .long 0
+ .long 0 // SizeOfRawData
+ .long 0 // PointerToRawData
+ .long 0 // PointerToRelocations
+ .long 0 // PointerToLineNumbers
+ .short 0 // NumberOfRelocations
+ .short 0 // NumberOfLineNumbers
+ .long 0x42100040 // Characteristics (section flags)
+
+
+ .ascii ".text"
+ .byte 0
+ .byte 0
+ .byte 0 // end of 0 padding of section name
+ .long _end - efi_header_end // VirtualSize
+ .long efi_header_end - _head // VirtualAddress
+ .long _edata - efi_header_end // SizeOfRawData
+ .long efi_header_end - _head // PointerToRawData
+
+ .long 0 // PointerToRelocations
+ .long 0 // PointerToLineNumbers
+ .short 0 // NumberOfRelocations
+ .short 0 // NumberOfLineNumbers
+ .long 0xe0500020 // Characteristics
+
+#ifdef CONFIG_DEBUG_EFI
+ /*
+ * The debug table is referenced via its Relative Virtual Address (RVA),
+ * which is only defined for those parts of the image that are covered
+ * by a section declaration. Since this header is not covered by any
+ * section, the debug table must be emitted elsewhere. So stick it in
+ * the .init.rodata section instead.
+ *
+ * Note that the EFI debug entry itself may legally have a zero RVA,
+ * which means we can simply put it right after the section headers.
+ */
+ __INITRODATA
+
+ .align 2
+efi_debug_table:
+ // EFI_IMAGE_DEBUG_DIRECTORY_ENTRY
+ .long 0 // Characteristics
+ .long 0 // TimeDateStamp
+ .short 0 // MajorVersion
+ .short 0 // MinorVersion
+ .long 2 // Type == EFI_IMAGE_DEBUG_TYPE_CODEVIEW
+ .long efi_debug_entry_size // SizeOfData
+ .long 0 // RVA
+ .long efi_debug_entry - _head // FileOffset
+
+ .set efi_debug_table_size, . - efi_debug_table
+ .previous
+
+efi_debug_entry:
+ // EFI_IMAGE_DEBUG_CODEVIEW_NB10_ENTRY
+ .ascii "NB10" // Signature
+ .long 0 // Unknown
+ .long 0 // Unknown2
+ .long 0 // Unknown3
+
+ .asciz VMLINUX_PATH
+
+ .set efi_debug_entry_size, . - efi_debug_entry
+#endif
+
+ /*
+ * EFI will load .text onwards at the 4k section alignment
+ * described in the PE/COFF header. To ensure that instruction
+ * sequences using an adrp and a :lo12: immediate will function
+ * correctly at this alignment, we must ensure that .text is
+ * placed at a 4k boundary in the Image to begin with.
+ */
+ .align 12
+efi_header_end:
+ .endm
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index c6cc82ec190b..f779a7483736 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -42,6 +42,8 @@
#include <asm/thread_info.h>
#include <asm/virt.h>

+#include "efi-header.S"
+
#define __PHYS_OFFSET (KERNEL_START - TEXT_OFFSET)

#if (TEXT_OFFSET & 0xfff) != 0
@@ -102,153 +104,7 @@ _head:
#ifdef CONFIG_EFI
.align 3
pe_header:
- .ascii "PE"
- .short 0
-coff_header:
- .short 0xaa64 // AArch64
- .short 2 // nr_sections
- .long 0 // TimeDateStamp
- .long 0 // PointerToSymbolTable
- .long 1 // NumberOfSymbols
- .short section_table - optional_header // SizeOfOptionalHeader
- .short 0x206 // Characteristics.
- // IMAGE_FILE_DEBUG_STRIPPED |
- // IMAGE_FILE_EXECUTABLE_IMAGE |
- // IMAGE_FILE_LINE_NUMS_STRIPPED
-optional_header:
- .short 0x20b // PE32+ format
- .byte 0x02 // MajorLinkerVersion
- .byte 0x14 // MinorLinkerVersion
- .long _end - efi_header_end // SizeOfCode
- .long 0 // SizeOfInitializedData
- .long 0 // SizeOfUninitializedData
- .long __efistub_entry - _head // AddressOfEntryPoint
- .long efi_header_end - _head // BaseOfCode
-
-extra_header_fields:
- .quad 0 // ImageBase
- .long 0x1000 // SectionAlignment
- .long PECOFF_FILE_ALIGNMENT // FileAlignment
- .short 0 // MajorOperatingSystemVersion
- .short 0 // MinorOperatingSystemVersion
- .short 0 // MajorImageVersion
- .short 0 // MinorImageVersion
- .short 0 // MajorSubsystemVersion
- .short 0 // MinorSubsystemVersion
- .long 0 // Win32VersionValue
-
- .long _end - _head // SizeOfImage
-
- // Everything before the kernel image is considered part of the header
- .long efi_header_end - _head // SizeOfHeaders
- .long 0 // CheckSum
- .short 0xa // Subsystem (EFI application)
- .short 0 // DllCharacteristics
- .quad 0 // SizeOfStackReserve
- .quad 0 // SizeOfStackCommit
- .quad 0 // SizeOfHeapReserve
- .quad 0 // SizeOfHeapCommit
- .long 0 // LoaderFlags
- .long (section_table - .) / 8 // NumberOfRvaAndSizes
-
- .quad 0 // ExportTable
- .quad 0 // ImportTable
- .quad 0 // ResourceTable
- .quad 0 // ExceptionTable
- .quad 0 // CertificationTable
- .quad 0 // BaseRelocationTable
-
-#ifdef CONFIG_DEBUG_EFI
- .long efi_debug_table - _head // DebugTable
- .long efi_debug_table_size
-#endif
-
- // Section table
-section_table:
-
- /*
- * The EFI application loader requires a relocation section
- * because EFI applications must be relocatable. This is a
- * dummy section as far as we are concerned.
- */
- .ascii ".reloc"
- .byte 0
- .byte 0 // end of 0 padding of section name
- .long 0
- .long 0
- .long 0 // SizeOfRawData
- .long 0 // PointerToRawData
- .long 0 // PointerToRelocations
- .long 0 // PointerToLineNumbers
- .short 0 // NumberOfRelocations
- .short 0 // NumberOfLineNumbers
- .long 0x42100040 // Characteristics (section flags)
-
-
- .ascii ".text"
- .byte 0
- .byte 0
- .byte 0 // end of 0 padding of section name
- .long _end - efi_header_end // VirtualSize
- .long efi_header_end - _head // VirtualAddress
- .long _edata - efi_header_end // SizeOfRawData
- .long efi_header_end - _head // PointerToRawData
-
- .long 0 // PointerToRelocations (0 for executables)
- .long 0 // PointerToLineNumbers (0 for executables)
- .short 0 // NumberOfRelocations (0 for executables)
- .short 0 // NumberOfLineNumbers (0 for executables)
- .long 0xe0500020 // Characteristics (section flags)
-
-#ifdef CONFIG_DEBUG_EFI
- /*
- * The debug table is referenced via its Relative Virtual Address (RVA),
- * which is only defined for those parts of the image that are covered
- * by a section declaration. Since this header is not covered by any
- * section, the debug table must be emitted elsewhere. So stick it in
- * the .init.rodata section instead.
- *
- * Note that the EFI debug entry itself may legally have a zero RVA,
- * which means we can simply put it right after the section headers.
- */
- __INITRODATA
-
- .align 2
-efi_debug_table:
- // EFI_IMAGE_DEBUG_DIRECTORY_ENTRY
- .long 0 // Characteristics
- .long 0 // TimeDateStamp
- .short 0 // MajorVersion
- .short 0 // MinorVersion
- .long 2 // Type == EFI_IMAGE_DEBUG_TYPE_CODEVIEW
- .long efi_debug_entry_size // SizeOfData
- .long 0 // RVA
- .long efi_debug_entry - _head // FileOffset
-
- .set efi_debug_table_size, . - efi_debug_table
- .previous
-
-efi_debug_entry:
- // EFI_IMAGE_DEBUG_CODEVIEW_NB10_ENTRY
- .ascii "NB10" // Signature
- .long 0 // Unknown
- .long 0 // Unknown2
- .long 0 // Unknown3
-
- .asciz VMLINUX_PATH
-
- .set efi_debug_entry_size, . - efi_debug_entry
-#endif
-
- /*
- * EFI will load .text onwards at the 4k section alignment
- * described in the PE/COFF header. To ensure that instruction
- * sequences using an adrp and a :lo12: immediate will function
- * correctly at this alignment, we must ensure that .text is
- * placed at a 4k boundary in the Image to begin with.
- */
- .align 12
-efi_header_end:
+ __EFI_PE_HEADER
#endif

__INIT
--
2.7.4