1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4  */
5 #ifndef _ASM_MODULE_H
6 #define _ASM_MODULE_H
7 
8 #include <asm/inst.h>
9 #include <asm-generic/module.h>
10 
11 #define RELA_STACK_DEPTH 16
12 
13 struct mod_section {
14 	int shndx;
15 	int num_entries;
16 	int max_entries;
17 };
18 
19 struct mod_arch_specific {
20 	struct mod_section got;
21 	struct mod_section plt;
22 	struct mod_section plt_idx;
23 
24 	/* For CONFIG_DYNAMIC_FTRACE */
25 	struct plt_entry *ftrace_trampolines;
26 };
27 
28 struct got_entry {
29 	Elf_Addr symbol_addr;
30 };
31 
32 struct plt_entry {
33 	u32 inst_lu12iw;
34 	u32 inst_lu32id;
35 	u32 inst_lu52id;
36 	u32 inst_jirl;
37 };
38 
39 struct plt_idx_entry {
40 	Elf_Addr symbol_addr;
41 };
42 
43 Elf_Addr module_emit_got_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr val);
44 Elf_Addr module_emit_plt_entry(struct module *mod, Elf_Shdr *sechdrs, Elf_Addr val);
45 
46 static inline struct got_entry emit_got_entry(Elf_Addr val)
47 {
48 	return (struct got_entry) { val };
49 }
50 
51 static inline struct plt_entry emit_plt_entry(unsigned long val)
52 {
53 	u32 lu12iw, lu32id, lu52id, jirl;
54 
55 	lu12iw = larch_insn_gen_lu12iw(LOONGARCH_GPR_T1, ADDR_IMM(val, LU12IW));
56 	lu32id = larch_insn_gen_lu32id(LOONGARCH_GPR_T1, ADDR_IMM(val, LU32ID));
57 	lu52id = larch_insn_gen_lu52id(LOONGARCH_GPR_T1, LOONGARCH_GPR_T1, ADDR_IMM(val, LU52ID));
58 	jirl = larch_insn_gen_jirl(0, LOONGARCH_GPR_T1, 0, (val & 0xfff));
59 
60 	return (struct plt_entry) { lu12iw, lu32id, lu52id, jirl };
61 }
62 
63 static inline struct plt_idx_entry emit_plt_idx_entry(unsigned long val)
64 {
65 	return (struct plt_idx_entry) { val };
66 }
67 
68 static inline int get_plt_idx(unsigned long val, Elf_Shdr *sechdrs, const struct mod_section *sec)
69 {
70 	int i;
71 	struct plt_idx_entry *plt_idx = (struct plt_idx_entry *)sechdrs[sec->shndx].sh_addr;
72 
73 	for (i = 0; i < sec->num_entries; i++) {
74 		if (plt_idx[i].symbol_addr == val)
75 			return i;
76 	}
77 
78 	return -1;
79 }
80 
81 static inline struct plt_entry *get_plt_entry(unsigned long val,
82 					      Elf_Shdr *sechdrs,
83 					      const struct mod_section *sec_plt,
84 					      const struct mod_section *sec_plt_idx)
85 {
86 	int plt_idx = get_plt_idx(val, sechdrs, sec_plt_idx);
87 	struct plt_entry *plt = (struct plt_entry *)sechdrs[sec_plt->shndx].sh_addr;
88 
89 	if (plt_idx < 0)
90 		return NULL;
91 
92 	return plt + plt_idx;
93 }
94 
95 static inline struct got_entry *get_got_entry(Elf_Addr val,
96 					      Elf_Shdr *sechdrs,
97 					      const struct mod_section *sec)
98 {
99 	int i;
100 	struct got_entry *got = (struct got_entry *)sechdrs[sec->shndx].sh_addr;
101 
102 	for (i = 0; i < sec->num_entries; i++)
103 		if (got[i].symbol_addr == val)
104 			return &got[i];
105 	return NULL;
106 }
107 
108 #endif /* _ASM_MODULE_H */
109