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13#include <linux/module.h>
14#include <linux/moduleloader.h>
15#include <linux/kernel.h>
16#include <linux/mm.h>
17#include <linux/elf.h>
18#include <linux/vmalloc.h>
19#include <linux/fs.h>
20#include <linux/string.h>
21#include <linux/gfp.h>
22
23#include <asm/pgtable.h>
24#include <asm/sections.h>
25#include <asm/smp_plat.h>
26#include <asm/unwind.h>
27
28#ifdef CONFIG_XIP_KERNEL
29
30
31
32
33
34
35#undef MODULES_VADDR
36#define MODULES_VADDR (((unsigned long)_etext + ~PMD_MASK) & PMD_MASK)
37#endif
38
39#ifdef CONFIG_MMU
40void *module_alloc(unsigned long size)
41{
42 return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
43 GFP_KERNEL, PAGE_KERNEL_EXEC, -1,
44 __builtin_return_address(0));
45}
46#endif
47
48int
49apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
50 unsigned int relindex, struct module *module)
51{
52 Elf32_Shdr *symsec = sechdrs + symindex;
53 Elf32_Shdr *relsec = sechdrs + relindex;
54 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
55 Elf32_Rel *rel = (void *)relsec->sh_addr;
56 unsigned int i;
57
58 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
59 unsigned long loc;
60 Elf32_Sym *sym;
61 const char *symname;
62 s32 offset;
63#ifdef CONFIG_THUMB2_KERNEL
64 u32 upper, lower, sign, j1, j2;
65#endif
66
67 offset = ELF32_R_SYM(rel->r_info);
68 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
69 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
70 module->name, relindex, i);
71 return -ENOEXEC;
72 }
73
74 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
75 symname = strtab + sym->st_name;
76
77 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
78 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
79 module->name, relindex, i, symname,
80 rel->r_offset, dstsec->sh_size);
81 return -ENOEXEC;
82 }
83
84 loc = dstsec->sh_addr + rel->r_offset;
85
86 switch (ELF32_R_TYPE(rel->r_info)) {
87 case R_ARM_NONE:
88
89 break;
90
91 case R_ARM_ABS32:
92 *(u32 *)loc += sym->st_value;
93 break;
94
95 case R_ARM_PC24:
96 case R_ARM_CALL:
97 case R_ARM_JUMP24:
98 offset = (*(u32 *)loc & 0x00ffffff) << 2;
99 if (offset & 0x02000000)
100 offset -= 0x04000000;
101
102 offset += sym->st_value - loc;
103 if (offset & 3 ||
104 offset <= (s32)0xfe000000 ||
105 offset >= (s32)0x02000000) {
106 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
107 module->name, relindex, i, symname,
108 ELF32_R_TYPE(rel->r_info), loc,
109 sym->st_value);
110 return -ENOEXEC;
111 }
112
113 offset >>= 2;
114
115 *(u32 *)loc &= 0xff000000;
116 *(u32 *)loc |= offset & 0x00ffffff;
117 break;
118
119 case R_ARM_V4BX:
120
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123
124 *(u32 *)loc &= 0xf000000f;
125 *(u32 *)loc |= 0x01a0f000;
126 break;
127
128 case R_ARM_PREL31:
129 offset = *(u32 *)loc + sym->st_value - loc;
130 *(u32 *)loc = offset & 0x7fffffff;
131 break;
132
133 case R_ARM_MOVW_ABS_NC:
134 case R_ARM_MOVT_ABS:
135 offset = *(u32 *)loc;
136 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
137 offset = (offset ^ 0x8000) - 0x8000;
138
139 offset += sym->st_value;
140 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
141 offset >>= 16;
142
143 *(u32 *)loc &= 0xfff0f000;
144 *(u32 *)loc |= ((offset & 0xf000) << 4) |
145 (offset & 0x0fff);
146 break;
147
148#ifdef CONFIG_THUMB2_KERNEL
149 case R_ARM_THM_CALL:
150 case R_ARM_THM_JUMP24:
151 upper = *(u16 *)loc;
152 lower = *(u16 *)(loc + 2);
153
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166
167 sign = (upper >> 10) & 1;
168 j1 = (lower >> 13) & 1;
169 j2 = (lower >> 11) & 1;
170 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
171 ((~(j2 ^ sign) & 1) << 22) |
172 ((upper & 0x03ff) << 12) |
173 ((lower & 0x07ff) << 1);
174 if (offset & 0x01000000)
175 offset -= 0x02000000;
176 offset += sym->st_value - loc;
177
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187 if ((ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
188 !(offset & 1)) ||
189 offset <= (s32)0xff000000 ||
190 offset >= (s32)0x01000000) {
191 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
192 module->name, relindex, i, symname,
193 ELF32_R_TYPE(rel->r_info), loc,
194 sym->st_value);
195 return -ENOEXEC;
196 }
197
198 sign = (offset >> 24) & 1;
199 j1 = sign ^ (~(offset >> 23) & 1);
200 j2 = sign ^ (~(offset >> 22) & 1);
201 *(u16 *)loc = (u16)((upper & 0xf800) | (sign << 10) |
202 ((offset >> 12) & 0x03ff));
203 *(u16 *)(loc + 2) = (u16)((lower & 0xd000) |
204 (j1 << 13) | (j2 << 11) |
205 ((offset >> 1) & 0x07ff));
206 break;
207
208 case R_ARM_THM_MOVW_ABS_NC:
209 case R_ARM_THM_MOVT_ABS:
210 upper = *(u16 *)loc;
211 lower = *(u16 *)(loc + 2);
212
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223 offset = ((upper & 0x000f) << 12) |
224 ((upper & 0x0400) << 1) |
225 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
226 offset = (offset ^ 0x8000) - 0x8000;
227 offset += sym->st_value;
228
229 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)
230 offset >>= 16;
231
232 *(u16 *)loc = (u16)((upper & 0xfbf0) |
233 ((offset & 0xf000) >> 12) |
234 ((offset & 0x0800) >> 1));
235 *(u16 *)(loc + 2) = (u16)((lower & 0x8f00) |
236 ((offset & 0x0700) << 4) |
237 (offset & 0x00ff));
238 break;
239#endif
240
241 default:
242 printk(KERN_ERR "%s: unknown relocation: %u\n",
243 module->name, ELF32_R_TYPE(rel->r_info));
244 return -ENOEXEC;
245 }
246 }
247 return 0;
248}
249
250struct mod_unwind_map {
251 const Elf_Shdr *unw_sec;
252 const Elf_Shdr *txt_sec;
253};
254
255static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
256 const Elf_Shdr *sechdrs, const char *name)
257{
258 const Elf_Shdr *s, *se;
259 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
260
261 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
262 if (strcmp(name, secstrs + s->sh_name) == 0)
263 return s;
264
265 return NULL;
266}
267
268extern void fixup_pv_table(const void *, unsigned long);
269extern void fixup_smp(const void *, unsigned long);
270
271int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
272 struct module *mod)
273{
274 const Elf_Shdr *s = NULL;
275#ifdef CONFIG_ARM_UNWIND
276 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
277 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
278 struct mod_unwind_map maps[ARM_SEC_MAX];
279 int i;
280
281 memset(maps, 0, sizeof(maps));
282
283 for (s = sechdrs; s < sechdrs_end; s++) {
284 const char *secname = secstrs + s->sh_name;
285
286 if (!(s->sh_flags & SHF_ALLOC))
287 continue;
288
289 if (strcmp(".ARM.exidx.init.text", secname) == 0)
290 maps[ARM_SEC_INIT].unw_sec = s;
291 else if (strcmp(".ARM.exidx", secname) == 0)
292 maps[ARM_SEC_CORE].unw_sec = s;
293 else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
294 maps[ARM_SEC_EXIT].unw_sec = s;
295 else if (strcmp(".init.text", secname) == 0)
296 maps[ARM_SEC_INIT].txt_sec = s;
297 else if (strcmp(".text", secname) == 0)
298 maps[ARM_SEC_CORE].txt_sec = s;
299 else if (strcmp(".exit.text", secname) == 0)
300 maps[ARM_SEC_EXIT].txt_sec = s;
301 }
302
303 for (i = 0; i < ARM_SEC_MAX; i++)
304 if (maps[i].unw_sec && maps[i].txt_sec)
305 mod->arch.unwind[i] =
306 unwind_table_add(maps[i].unw_sec->sh_addr,
307 maps[i].unw_sec->sh_size,
308 maps[i].txt_sec->sh_addr,
309 maps[i].txt_sec->sh_size);
310#endif
311#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
312 s = find_mod_section(hdr, sechdrs, ".pv_table");
313 if (s)
314 fixup_pv_table((void *)s->sh_addr, s->sh_size);
315#endif
316 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
317 if (s && !is_smp())
318#ifdef CONFIG_SMP_ON_UP
319 fixup_smp((void *)s->sh_addr, s->sh_size);
320#else
321 return -EINVAL;
322#endif
323 return 0;
324}
325
326void
327module_arch_cleanup(struct module *mod)
328{
329#ifdef CONFIG_ARM_UNWIND
330 int i;
331
332 for (i = 0; i < ARM_SEC_MAX; i++)
333 if (mod->arch.unwind[i])
334 unwind_table_del(mod->arch.unwind[i]);
335#endif
336}
337
