1/* SPDX-License-Identifier: GPL-2.0 */
2#include <asm/vdso.h>
3
4/*
5 * Linker script for vDSO.  This is an ELF shared object prelinked to
6 * its virtual address, and with only one read-only segment.
7 * This script controls its layout.
8 */
9
10#if defined(BUILD_VDSO64)
11# define SHDR_SIZE 64
12#elif defined(BUILD_VDSO32) || defined(BUILD_VDSOX32)
13# define SHDR_SIZE 40
14#else
15# error unknown VDSO target
16#endif
17
18#define NUM_FAKE_SHDRS 13
19
20SECTIONS
21{
22	/*
23	 * User/kernel shared data is before the vDSO.  This may be a little
24	 * uglier than putting it after the vDSO, but it avoids issues with
25	 * non-allocatable things that dangle past the end of the PT_LOAD
26	 * segment.
27	 */
28
29	vvar_start = . - 3 * PAGE_SIZE;
30	vvar_page = vvar_start;
31
32	/* Place all vvars at the offsets in asm/vvar.h. */
33#define EMIT_VVAR(name, offset) vvar_ ## name = vvar_page + offset;
34#define __VVAR_KERNEL_LDS
35#include <asm/vvar.h>
36#undef __VVAR_KERNEL_LDS
37#undef EMIT_VVAR
38
39	pvclock_page = vvar_start + PAGE_SIZE;
40	hvclock_page = vvar_start + 2 * PAGE_SIZE;
41
42	. = SIZEOF_HEADERS;
43
44	.hash		: { *(.hash) }			:text
45	.gnu.hash	: { *(.gnu.hash) }
46	.dynsym		: { *(.dynsym) }
47	.dynstr		: { *(.dynstr) }
48	.gnu.version	: { *(.gnu.version) }
49	.gnu.version_d	: { *(.gnu.version_d) }
50	.gnu.version_r	: { *(.gnu.version_r) }
51
52	.dynamic	: { *(.dynamic) }		:text	:dynamic
53
54	.rodata		: {
55		*(.rodata*)
56		*(.data*)
57		*(.sdata*)
58		*(.got.plt) *(.got)
59		*(.gnu.linkonce.d.*)
60		*(.bss*)
61		*(.dynbss*)
62		*(.gnu.linkonce.b.*)
63
64		/*
65		 * Ideally this would live in a C file, but that won't
66		 * work cleanly for x32 until we start building the x32
67		 * C code using an x32 toolchain.
68		 */
69		VDSO_FAKE_SECTION_TABLE_START = .;
70		. = . + NUM_FAKE_SHDRS * SHDR_SIZE;
71		VDSO_FAKE_SECTION_TABLE_END = .;
72	}						:text
73
74	.fake_shstrtab	: { *(.fake_shstrtab) }		:text
75
76
77	.note		: { *(.note.*) }		:text	:note
78
79	.eh_frame_hdr	: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
80	.eh_frame	: { KEEP (*(.eh_frame)) }	:text
81
82
83	/*
84	 * Text is well-separated from actual data: there's plenty of
85	 * stuff that isn't used at runtime in between.
86	 */
87
88	.text		: { *(.text*) }			:text	=0x90909090,
89
90	/*
91	 * At the end so that eu-elflint stays happy when vdso2c strips
92	 * these.  A better implementation would avoid allocating space
93	 * for these.
94	 */
95	.altinstructions	: { *(.altinstructions) }	:text
96	.altinstr_replacement	: { *(.altinstr_replacement) }	:text
97
98	/DISCARD/ : {
99		*(.discard)
100		*(.discard.*)
101		*(__bug_table)
102	}
103}
104
105/*
106 * Very old versions of ld do not recognize this name token; use the constant.
107 */
108#define PT_GNU_EH_FRAME	0x6474e550
109
110/*
111 * We must supply the ELF program headers explicitly to get just one
112 * PT_LOAD segment, and set the flags explicitly to make segments read-only.
113 */
114PHDRS
115{
116	text		PT_LOAD		FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
117	dynamic		PT_DYNAMIC	FLAGS(4);		/* PF_R */
118	note		PT_NOTE		FLAGS(4);		/* PF_R */
119	eh_frame_hdr	PT_GNU_EH_FRAME;
120}
121