1 // SPDX-License-Identifier: GPL-2.0-or-later
4 * Copyright (C) 2017 Zihao Yu
9 #include <linux/errno.h>
10 #include <linux/moduleloader.h>
12 static int apply_r_riscv_32_rela(struct module *me, u32 *location, Elf_Addr v)
15 pr_err("%s: value %016llx out of range for 32-bit field\n",
16 me->name, (long long)v);
23 static int apply_r_riscv_64_rela(struct module *me, u32 *location, Elf_Addr v)
29 static int apply_r_riscv_branch_rela(struct module *me, u32 *location,
32 ptrdiff_t offset = (void *)v - (void *)location;
33 u32 imm12 = (offset & 0x1000) << (31 - 12);
34 u32 imm11 = (offset & 0x800) >> (11 - 7);
35 u32 imm10_5 = (offset & 0x7e0) << (30 - 10);
36 u32 imm4_1 = (offset & 0x1e) << (11 - 4);
38 *location = (*location & 0x1fff07f) | imm12 | imm11 | imm10_5 | imm4_1;
42 static int apply_r_riscv_jal_rela(struct module *me, u32 *location,
45 ptrdiff_t offset = (void *)v - (void *)location;
46 u32 imm20 = (offset & 0x100000) << (31 - 20);
47 u32 imm19_12 = (offset & 0xff000);
48 u32 imm11 = (offset & 0x800) << (20 - 11);
49 u32 imm10_1 = (offset & 0x7fe) << (30 - 10);
51 *location = (*location & 0xfff) | imm20 | imm19_12 | imm11 | imm10_1;
55 static int apply_r_riscv_rcv_branch_rela(struct module *me, u32 *location,
58 ptrdiff_t offset = (void *)v - (void *)location;
59 u16 imm8 = (offset & 0x100) << (12 - 8);
60 u16 imm7_6 = (offset & 0xc0) >> (6 - 5);
61 u16 imm5 = (offset & 0x20) >> (5 - 2);
62 u16 imm4_3 = (offset & 0x18) << (12 - 5);
63 u16 imm2_1 = (offset & 0x6) << (12 - 10);
65 *(u16 *)location = (*(u16 *)location & 0xe383) |
66 imm8 | imm7_6 | imm5 | imm4_3 | imm2_1;
70 static int apply_r_riscv_rvc_jump_rela(struct module *me, u32 *location,
73 ptrdiff_t offset = (void *)v - (void *)location;
74 u16 imm11 = (offset & 0x800) << (12 - 11);
75 u16 imm10 = (offset & 0x400) >> (10 - 8);
76 u16 imm9_8 = (offset & 0x300) << (12 - 11);
77 u16 imm7 = (offset & 0x80) >> (7 - 6);
78 u16 imm6 = (offset & 0x40) << (12 - 11);
79 u16 imm5 = (offset & 0x20) >> (5 - 2);
80 u16 imm4 = (offset & 0x10) << (12 - 5);
81 u16 imm3_1 = (offset & 0xe) << (12 - 10);
83 *(u16 *)location = (*(u16 *)location & 0xe003) |
84 imm11 | imm10 | imm9_8 | imm7 | imm6 | imm5 | imm4 | imm3_1;
88 static int apply_r_riscv_pcrel_hi20_rela(struct module *me, u32 *location,
91 ptrdiff_t offset = (void *)v - (void *)location;
94 if (offset != (s32)offset) {
96 "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
97 me->name, (long long)v, location);
101 hi20 = (offset + 0x800) & 0xfffff000;
102 *location = (*location & 0xfff) | hi20;
106 static int apply_r_riscv_pcrel_lo12_i_rela(struct module *me, u32 *location,
110 * v is the lo12 value to fill. It is calculated before calling this
113 *location = (*location & 0xfffff) | ((v & 0xfff) << 20);
117 static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, u32 *location,
121 * v is the lo12 value to fill. It is calculated before calling this
124 u32 imm11_5 = (v & 0xfe0) << (31 - 11);
125 u32 imm4_0 = (v & 0x1f) << (11 - 4);
127 *location = (*location & 0x1fff07f) | imm11_5 | imm4_0;
131 static int apply_r_riscv_hi20_rela(struct module *me, u32 *location,
136 if (IS_ENABLED(CONFIG_CMODEL_MEDLOW)) {
138 "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
139 me->name, (long long)v, location);
143 hi20 = ((s32)v + 0x800) & 0xfffff000;
144 *location = (*location & 0xfff) | hi20;
148 static int apply_r_riscv_lo12_i_rela(struct module *me, u32 *location,
151 /* Skip medlow checking because of filtering by HI20 already */
152 s32 hi20 = ((s32)v + 0x800) & 0xfffff000;
153 s32 lo12 = ((s32)v - hi20);
154 *location = (*location & 0xfffff) | ((lo12 & 0xfff) << 20);
158 static int apply_r_riscv_lo12_s_rela(struct module *me, u32 *location,
161 /* Skip medlow checking because of filtering by HI20 already */
162 s32 hi20 = ((s32)v + 0x800) & 0xfffff000;
163 s32 lo12 = ((s32)v - hi20);
164 u32 imm11_5 = (lo12 & 0xfe0) << (31 - 11);
165 u32 imm4_0 = (lo12 & 0x1f) << (11 - 4);
166 *location = (*location & 0x1fff07f) | imm11_5 | imm4_0;
170 static int apply_r_riscv_got_hi20_rela(struct module *me, u32 *location,
173 ptrdiff_t offset = (void *)v - (void *)location;
176 /* Always emit the got entry */
177 if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) {
178 offset = module_emit_got_entry(me, v);
179 offset = (void *)offset - (void *)location;
182 "%s: can not generate the GOT entry for symbol = %016llx from PC = %p\n",
183 me->name, (long long)v, location);
187 hi20 = (offset + 0x800) & 0xfffff000;
188 *location = (*location & 0xfff) | hi20;
192 static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location,
195 ptrdiff_t offset = (void *)v - (void *)location;
199 if (offset != fill_v) {
200 /* Only emit the plt entry if offset over 32-bit range */
201 if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) {
202 offset = module_emit_plt_entry(me, v);
203 offset = (void *)offset - (void *)location;
206 "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
207 me->name, (long long)v, location);
212 hi20 = (offset + 0x800) & 0xfffff000;
213 lo12 = (offset - hi20) & 0xfff;
214 *location = (*location & 0xfff) | hi20;
215 *(location + 1) = (*(location + 1) & 0xfffff) | (lo12 << 20);
219 static int apply_r_riscv_call_rela(struct module *me, u32 *location,
222 ptrdiff_t offset = (void *)v - (void *)location;
226 if (offset != fill_v) {
228 "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
229 me->name, (long long)v, location);
233 hi20 = (offset + 0x800) & 0xfffff000;
234 lo12 = (offset - hi20) & 0xfff;
235 *location = (*location & 0xfff) | hi20;
236 *(location + 1) = (*(location + 1) & 0xfffff) | (lo12 << 20);
240 static int apply_r_riscv_relax_rela(struct module *me, u32 *location,
246 static int apply_r_riscv_align_rela(struct module *me, u32 *location,
250 "%s: The unexpected relocation type 'R_RISCV_ALIGN' from PC = %p\n",
255 static int apply_r_riscv_add32_rela(struct module *me, u32 *location,
258 *(u32 *)location += (u32)v;
262 static int apply_r_riscv_sub32_rela(struct module *me, u32 *location,
265 *(u32 *)location -= (u32)v;
269 static int (*reloc_handlers_rela[]) (struct module *me, u32 *location,
271 [R_RISCV_32] = apply_r_riscv_32_rela,
272 [R_RISCV_64] = apply_r_riscv_64_rela,
273 [R_RISCV_BRANCH] = apply_r_riscv_branch_rela,
274 [R_RISCV_JAL] = apply_r_riscv_jal_rela,
275 [R_RISCV_RVC_BRANCH] = apply_r_riscv_rcv_branch_rela,
276 [R_RISCV_RVC_JUMP] = apply_r_riscv_rvc_jump_rela,
277 [R_RISCV_PCREL_HI20] = apply_r_riscv_pcrel_hi20_rela,
278 [R_RISCV_PCREL_LO12_I] = apply_r_riscv_pcrel_lo12_i_rela,
279 [R_RISCV_PCREL_LO12_S] = apply_r_riscv_pcrel_lo12_s_rela,
280 [R_RISCV_HI20] = apply_r_riscv_hi20_rela,
281 [R_RISCV_LO12_I] = apply_r_riscv_lo12_i_rela,
282 [R_RISCV_LO12_S] = apply_r_riscv_lo12_s_rela,
283 [R_RISCV_GOT_HI20] = apply_r_riscv_got_hi20_rela,
284 [R_RISCV_CALL_PLT] = apply_r_riscv_call_plt_rela,
285 [R_RISCV_CALL] = apply_r_riscv_call_rela,
286 [R_RISCV_RELAX] = apply_r_riscv_relax_rela,
287 [R_RISCV_ALIGN] = apply_r_riscv_align_rela,
288 [R_RISCV_ADD32] = apply_r_riscv_add32_rela,
289 [R_RISCV_SUB32] = apply_r_riscv_sub32_rela,
292 int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
293 unsigned int symindex, unsigned int relsec,
296 Elf_Rela *rel = (void *) sechdrs[relsec].sh_addr;
297 int (*handler)(struct module *me, u32 *location, Elf_Addr v);
300 unsigned int i, type;
304 pr_debug("Applying relocate section %u to %u\n", relsec,
305 sechdrs[relsec].sh_info);
307 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
308 /* This is where to make the change */
309 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
311 /* This is the symbol it is referring to */
312 sym = (Elf_Sym *)sechdrs[symindex].sh_addr
313 + ELF_RISCV_R_SYM(rel[i].r_info);
314 if (IS_ERR_VALUE(sym->st_value)) {
315 /* Ignore unresolved weak symbol */
316 if (ELF_ST_BIND(sym->st_info) == STB_WEAK)
318 pr_warning("%s: Unknown symbol %s\n",
319 me->name, strtab + sym->st_name);
323 type = ELF_RISCV_R_TYPE(rel[i].r_info);
325 if (type < ARRAY_SIZE(reloc_handlers_rela))
326 handler = reloc_handlers_rela[type];
331 pr_err("%s: Unknown relocation type %u\n",
336 v = sym->st_value + rel[i].r_addend;
338 if (type == R_RISCV_PCREL_LO12_I || type == R_RISCV_PCREL_LO12_S) {
341 for (j = 0; j < sechdrs[relsec].sh_size / sizeof(*rel); j++) {
342 unsigned long hi20_loc =
343 sechdrs[sechdrs[relsec].sh_info].sh_addr
345 u32 hi20_type = ELF_RISCV_R_TYPE(rel[j].r_info);
347 /* Find the corresponding HI20 relocation entry */
348 if (hi20_loc == sym->st_value
349 && (hi20_type == R_RISCV_PCREL_HI20
350 || hi20_type == R_RISCV_GOT_HI20)) {
353 (Elf_Sym *)sechdrs[symindex].sh_addr
354 + ELF_RISCV_R_SYM(rel[j].r_info);
355 unsigned long hi20_sym_val =
360 size_t offset = hi20_sym_val - hi20_loc;
361 if (IS_ENABLED(CONFIG_MODULE_SECTIONS)
362 && hi20_type == R_RISCV_GOT_HI20) {
363 offset = module_emit_got_entry(
365 offset = offset - hi20_loc;
367 hi20 = (offset + 0x800) & 0xfffff000;
368 lo12 = offset - hi20;
374 if (j == sechdrs[relsec].sh_size / sizeof(*rel)) {
376 "%s: Can not find HI20 relocation information\n",
382 res = handler(me, location, v);