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16#include <linux/module.h>
17#include <linux/moduleloader.h>
18#include <linux/elf.h>
19#include <linux/vmalloc.h>
20#include <linux/fs.h>
21#include <linux/string.h>
22#include <linux/kernel.h>
23#include <linux/cache.h>
24
25#undef DEBUG_RELOCATE
26
27static int
28decode_calln_opcode (unsigned char *location)
29{
30#ifdef __XTENSA_EB__
31 return (location[0] & 0xf0) == 0x50;
32#endif
33#ifdef __XTENSA_EL__
34 return (location[0] & 0xf) == 0x5;
35#endif
36}
37
38static int
39decode_l32r_opcode (unsigned char *location)
40{
41#ifdef __XTENSA_EB__
42 return (location[0] & 0xf0) == 0x10;
43#endif
44#ifdef __XTENSA_EL__
45 return (location[0] & 0xf) == 0x1;
46#endif
47}
48
49int apply_relocate_add(Elf32_Shdr *sechdrs,
50 const char *strtab,
51 unsigned int symindex,
52 unsigned int relsec,
53 struct module *mod)
54{
55 unsigned int i;
56 Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
57 Elf32_Sym *sym;
58 unsigned char *location;
59 uint32_t value;
60
61#ifdef DEBUG_RELOCATE
62 printk("Applying relocate section %u to %u\n", relsec,
63 sechdrs[relsec].sh_info);
64#endif
65 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
66 location = (char *)sechdrs[sechdrs[relsec].sh_info].sh_addr
67 + rela[i].r_offset;
68 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
69 + ELF32_R_SYM(rela[i].r_info);
70 value = sym->st_value + rela[i].r_addend;
71
72 switch (ELF32_R_TYPE(rela[i].r_info)) {
73 case R_XTENSA_NONE:
74 case R_XTENSA_DIFF8:
75 case R_XTENSA_DIFF16:
76 case R_XTENSA_DIFF32:
77 case R_XTENSA_ASM_EXPAND:
78 break;
79
80 case R_XTENSA_32:
81 case R_XTENSA_PLT:
82 *(uint32_t *)location += value;
83 break;
84
85 case R_XTENSA_SLOT0_OP:
86 if (decode_calln_opcode(location)) {
87 value -= ((unsigned long)location & -4) + 4;
88 if ((value & 3) != 0 ||
89 ((value + (1 << 19)) >> 20) != 0) {
90 printk("%s: relocation out of range, "
91 "section %d reloc %d "
92 "sym '%s'\n",
93 mod->name, relsec, i,
94 strtab + sym->st_name);
95 return -ENOEXEC;
96 }
97 value = (signed int)value >> 2;
98#ifdef __XTENSA_EB__
99 location[0] = ((location[0] & ~0x3) |
100 ((value >> 16) & 0x3));
101 location[1] = (value >> 8) & 0xff;
102 location[2] = value & 0xff;
103#endif
104#ifdef __XTENSA_EL__
105 location[0] = ((location[0] & ~0xc0) |
106 ((value << 6) & 0xc0));
107 location[1] = (value >> 2) & 0xff;
108 location[2] = (value >> 10) & 0xff;
109#endif
110 } else if (decode_l32r_opcode(location)) {
111 value -= (((unsigned long)location + 3) & -4);
112 if ((value & 3) != 0 ||
113 (signed int)value >> 18 != -1) {
114 printk("%s: relocation out of range, "
115 "section %d reloc %d "
116 "sym '%s'\n",
117 mod->name, relsec, i,
118 strtab + sym->st_name);
119 return -ENOEXEC;
120 }
121 value = (signed int)value >> 2;
122
123#ifdef __XTENSA_EB__
124 location[1] = (value >> 8) & 0xff;
125 location[2] = value & 0xff;
126#endif
127#ifdef __XTENSA_EL__
128 location[1] = value & 0xff;
129 location[2] = (value >> 8) & 0xff;
130#endif
131 }
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142
143 break;
144
145 case R_XTENSA_SLOT1_OP:
146 case R_XTENSA_SLOT2_OP:
147 case R_XTENSA_SLOT3_OP:
148 case R_XTENSA_SLOT4_OP:
149 case R_XTENSA_SLOT5_OP:
150 case R_XTENSA_SLOT6_OP:
151 case R_XTENSA_SLOT7_OP:
152 case R_XTENSA_SLOT8_OP:
153 case R_XTENSA_SLOT9_OP:
154 case R_XTENSA_SLOT10_OP:
155 case R_XTENSA_SLOT11_OP:
156 case R_XTENSA_SLOT12_OP:
157 case R_XTENSA_SLOT13_OP:
158 case R_XTENSA_SLOT14_OP:
159 printk("%s: unexpected FLIX relocation: %u\n",
160 mod->name,
161 ELF32_R_TYPE(rela[i].r_info));
162 return -ENOEXEC;
163
164 case R_XTENSA_SLOT0_ALT:
165 case R_XTENSA_SLOT1_ALT:
166 case R_XTENSA_SLOT2_ALT:
167 case R_XTENSA_SLOT3_ALT:
168 case R_XTENSA_SLOT4_ALT:
169 case R_XTENSA_SLOT5_ALT:
170 case R_XTENSA_SLOT6_ALT:
171 case R_XTENSA_SLOT7_ALT:
172 case R_XTENSA_SLOT8_ALT:
173 case R_XTENSA_SLOT9_ALT:
174 case R_XTENSA_SLOT10_ALT:
175 case R_XTENSA_SLOT11_ALT:
176 case R_XTENSA_SLOT12_ALT:
177 case R_XTENSA_SLOT13_ALT:
178 case R_XTENSA_SLOT14_ALT:
179 printk("%s: unexpected ALT relocation: %u\n",
180 mod->name,
181 ELF32_R_TYPE(rela[i].r_info));
182 return -ENOEXEC;
183
184 default:
185 printk("%s: unexpected relocation: %u\n",
186 mod->name,
187 ELF32_R_TYPE(rela[i].r_info));
188 return -ENOEXEC;
189 }
190 }
191 return 0;
192}
193
