1  /* SPDX-License-Identifier: GPL-2.0 */
2  /*
3   * Copyright (C) 2020 Google LLC.
4   * Written by David Brazdil <dbrazdil@google.com>
5   */
6  
7  #ifndef __ARM64_HYP_IMAGE_H__
8  #define __ARM64_HYP_IMAGE_H__
9  
10  #define __HYP_CONCAT(a, b)	a ## b
11  #define HYP_CONCAT(a, b)	__HYP_CONCAT(a, b)
12  
13  #ifndef __KVM_NVHE_HYPERVISOR__
14  /*
15   * KVM nVHE code has its own symbol namespace prefixed with __kvm_nvhe_,
16   * to separate it from the kernel proper.
17   */
18  #define kvm_nvhe_sym(sym)	__kvm_nvhe_##sym
19  #else
20  #define kvm_nvhe_sym(sym)	sym
21  #endif
22  
23  #ifdef LINKER_SCRIPT
24  
25  /*
26   * KVM nVHE ELF section names are prefixed with .hyp, to separate them
27   * from the kernel proper.
28   */
29  #define HYP_SECTION_NAME(NAME)	.hyp##NAME
30  
31  /* Symbol defined at the beginning of each hyp section. */
32  #define HYP_SECTION_SYMBOL_NAME(NAME) \
33  	HYP_CONCAT(__hyp_section_, HYP_SECTION_NAME(NAME))
34  
35  /*
36   * Helper to generate linker script statements starting a hyp section.
37   *
38   * A symbol with a well-known name is defined at the first byte. This
39   * is used as a base for hyp relocations (see gen-hyprel.c). It must
40   * be defined inside the section so the linker of `vmlinux` cannot
41   * separate it from the section data.
42   */
43  #define BEGIN_HYP_SECTION(NAME)				\
44  	HYP_SECTION_NAME(NAME) : {			\
45  		HYP_SECTION_SYMBOL_NAME(NAME) = .;
46  
47  /* Helper to generate linker script statements ending a hyp section. */
48  #define END_HYP_SECTION					\
49  	}
50  
51  /* Defines an ELF hyp section from input section @NAME and its subsections. */
52  #define HYP_SECTION(NAME)			\
53  	BEGIN_HYP_SECTION(NAME)			\
54  		*(NAME NAME##.*)		\
55  	END_HYP_SECTION
56  
57  /*
58   * Defines a linker script alias of a kernel-proper symbol referenced by
59   * KVM nVHE hyp code.
60   */
61  #define KVM_NVHE_ALIAS(sym)	kvm_nvhe_sym(sym) = sym;
62  
63  /* Defines a linker script alias for KVM nVHE hyp symbols */
64  #define KVM_NVHE_ALIAS_HYP(first, sec)	kvm_nvhe_sym(first) = kvm_nvhe_sym(sec);
65  
66  #endif /* LINKER_SCRIPT */
67  
68  #endif /* __ARM64_HYP_IMAGE_H__ */
69