2 * linux/arch/arm/kernel/module.c
4 * Copyright (C) 2002 Russell King.
5 * Modified for nommu by Hyok S. Choi
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * Module allocation method suggested by Andi Kleen.
13 #include <linux/module.h>
14 #include <linux/moduleloader.h>
15 #include <linux/kernel.h>
17 #include <linux/elf.h>
18 #include <linux/vmalloc.h>
20 #include <linux/string.h>
21 #include <linux/gfp.h>
23 #include <asm/pgtable.h>
24 #include <asm/sections.h>
25 #include <asm/smp_plat.h>
26 #include <asm/unwind.h>
28 #ifdef CONFIG_XIP_KERNEL
30 * The XIP kernel text is mapped in the module area for modules and
31 * some other stuff to work without any indirect relocations.
32 * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
33 * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
36 #define MODULES_VADDR (((unsigned long)_etext + ~PGDIR_MASK) & PGDIR_MASK)
40 void *module_alloc(unsigned long size)
42 return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
43 GFP_KERNEL, PAGE_KERNEL_EXEC, -1,
44 __builtin_return_address(0));
46 #else /* CONFIG_MMU */
47 void *module_alloc(unsigned long size)
49 return size == 0 ? NULL : vmalloc(size);
51 #endif /* !CONFIG_MMU */
53 void module_free(struct module *module, void *region)
58 int module_frob_arch_sections(Elf_Ehdr *hdr,
67 apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
68 unsigned int relindex, struct module *module)
70 Elf32_Shdr *symsec = sechdrs + symindex;
71 Elf32_Shdr *relsec = sechdrs + relindex;
72 Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
73 Elf32_Rel *rel = (void *)relsec->sh_addr;
76 for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
81 #ifdef CONFIG_THUMB2_KERNEL
82 u32 upper, lower, sign, j1, j2;
85 offset = ELF32_R_SYM(rel->r_info);
86 if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
87 pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
88 module->name, relindex, i);
92 sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
93 symname = strtab + sym->st_name;
95 if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
96 pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
97 module->name, relindex, i, symname,
98 rel->r_offset, dstsec->sh_size);
102 loc = dstsec->sh_addr + rel->r_offset;
104 switch (ELF32_R_TYPE(rel->r_info)) {
110 *(u32 *)loc += sym->st_value;
116 offset = (*(u32 *)loc & 0x00ffffff) << 2;
117 if (offset & 0x02000000)
118 offset -= 0x04000000;
120 offset += sym->st_value - loc;
122 offset <= (s32)0xfe000000 ||
123 offset >= (s32)0x02000000) {
124 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
125 module->name, relindex, i, symname,
126 ELF32_R_TYPE(rel->r_info), loc,
133 *(u32 *)loc &= 0xff000000;
134 *(u32 *)loc |= offset & 0x00ffffff;
138 /* Preserve Rm and the condition code. Alter
139 * other bits to re-code instruction as
142 *(u32 *)loc &= 0xf000000f;
143 *(u32 *)loc |= 0x01a0f000;
147 offset = *(u32 *)loc + sym->st_value - loc;
148 *(u32 *)loc = offset & 0x7fffffff;
151 case R_ARM_MOVW_ABS_NC:
153 offset = *(u32 *)loc;
154 offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
155 offset = (offset ^ 0x8000) - 0x8000;
157 offset += sym->st_value;
158 if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
161 *(u32 *)loc &= 0xfff0f000;
162 *(u32 *)loc |= ((offset & 0xf000) << 4) |
166 #ifdef CONFIG_THUMB2_KERNEL
168 case R_ARM_THM_JUMP24:
170 lower = *(u16 *)(loc + 2);
173 * 25 bit signed address range (Thumb-2 BL and B.W
175 * S:I1:I2:imm10:imm11:0
177 * S = upper[10] = offset[24]
178 * I1 = ~(J1 ^ S) = offset[23]
179 * I2 = ~(J2 ^ S) = offset[22]
180 * imm10 = upper[9:0] = offset[21:12]
181 * imm11 = lower[10:0] = offset[11:1]
185 sign = (upper >> 10) & 1;
186 j1 = (lower >> 13) & 1;
187 j2 = (lower >> 11) & 1;
188 offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
189 ((~(j2 ^ sign) & 1) << 22) |
190 ((upper & 0x03ff) << 12) |
191 ((lower & 0x07ff) << 1);
192 if (offset & 0x01000000)
193 offset -= 0x02000000;
194 offset += sym->st_value - loc;
197 * For function symbols, only Thumb addresses are
198 * allowed (no interworking).
200 * For non-function symbols, the destination
201 * has no specific ARM/Thumb disposition, so
202 * the branch is resolved under the assumption
203 * that interworking is not required.
205 if ((ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
207 offset <= (s32)0xff000000 ||
208 offset >= (s32)0x01000000) {
209 pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
210 module->name, relindex, i, symname,
211 ELF32_R_TYPE(rel->r_info), loc,
216 sign = (offset >> 24) & 1;
217 j1 = sign ^ (~(offset >> 23) & 1);
218 j2 = sign ^ (~(offset >> 22) & 1);
219 *(u16 *)loc = (u16)((upper & 0xf800) | (sign << 10) |
220 ((offset >> 12) & 0x03ff));
221 *(u16 *)(loc + 2) = (u16)((lower & 0xd000) |
222 (j1 << 13) | (j2 << 11) |
223 ((offset >> 1) & 0x07ff));
226 case R_ARM_THM_MOVW_ABS_NC:
227 case R_ARM_THM_MOVT_ABS:
229 lower = *(u16 *)(loc + 2);
232 * MOVT/MOVW instructions encoding in Thumb-2:
236 * imm3 = lower[14:12]
239 * imm16 = imm4:i:imm3:imm8
241 offset = ((upper & 0x000f) << 12) |
242 ((upper & 0x0400) << 1) |
243 ((lower & 0x7000) >> 4) | (lower & 0x00ff);
244 offset = (offset ^ 0x8000) - 0x8000;
245 offset += sym->st_value;
247 if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)
250 *(u16 *)loc = (u16)((upper & 0xfbf0) |
251 ((offset & 0xf000) >> 12) |
252 ((offset & 0x0800) >> 1));
253 *(u16 *)(loc + 2) = (u16)((lower & 0x8f00) |
254 ((offset & 0x0700) << 4) |
260 printk(KERN_ERR "%s: unknown relocation: %u\n",
261 module->name, ELF32_R_TYPE(rel->r_info));
269 apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
270 unsigned int symindex, unsigned int relsec, struct module *module)
272 printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n",
277 struct mod_unwind_map {
278 const Elf_Shdr *unw_sec;
279 const Elf_Shdr *txt_sec;
282 static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
283 const Elf_Shdr *sechdrs, const char *name)
285 const Elf_Shdr *s, *se;
286 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
288 for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
289 if (strcmp(name, secstrs + s->sh_name) == 0)
295 extern void fixup_pv_table(const void *, unsigned long);
296 extern void fixup_smp(const void *, unsigned long);
298 int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
301 const Elf_Shdr *s = NULL;
302 #ifdef CONFIG_ARM_UNWIND
303 const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
304 const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
305 struct mod_unwind_map maps[ARM_SEC_MAX];
308 memset(maps, 0, sizeof(maps));
310 for (s = sechdrs; s < sechdrs_end; s++) {
311 const char *secname = secstrs + s->sh_name;
313 if (!(s->sh_flags & SHF_ALLOC))
316 if (strcmp(".ARM.exidx.init.text", secname) == 0)
317 maps[ARM_SEC_INIT].unw_sec = s;
318 else if (strcmp(".ARM.exidx.devinit.text", secname) == 0)
319 maps[ARM_SEC_DEVINIT].unw_sec = s;
320 else if (strcmp(".ARM.exidx", secname) == 0)
321 maps[ARM_SEC_CORE].unw_sec = s;
322 else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
323 maps[ARM_SEC_EXIT].unw_sec = s;
324 else if (strcmp(".ARM.exidx.devexit.text", secname) == 0)
325 maps[ARM_SEC_DEVEXIT].unw_sec = s;
326 else if (strcmp(".init.text", secname) == 0)
327 maps[ARM_SEC_INIT].txt_sec = s;
328 else if (strcmp(".devinit.text", secname) == 0)
329 maps[ARM_SEC_DEVINIT].txt_sec = s;
330 else if (strcmp(".text", secname) == 0)
331 maps[ARM_SEC_CORE].txt_sec = s;
332 else if (strcmp(".exit.text", secname) == 0)
333 maps[ARM_SEC_EXIT].txt_sec = s;
334 else if (strcmp(".devexit.text", secname) == 0)
335 maps[ARM_SEC_DEVEXIT].txt_sec = s;
338 for (i = 0; i < ARM_SEC_MAX; i++)
339 if (maps[i].unw_sec && maps[i].txt_sec)
340 mod->arch.unwind[i] =
341 unwind_table_add(maps[i].unw_sec->sh_addr,
342 maps[i].unw_sec->sh_size,
343 maps[i].txt_sec->sh_addr,
344 maps[i].txt_sec->sh_size);
346 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
347 s = find_mod_section(hdr, sechdrs, ".pv_table");
349 fixup_pv_table((void *)s->sh_addr, s->sh_size);
351 s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
353 fixup_smp((void *)s->sh_addr, s->sh_size);
358 module_arch_cleanup(struct module *mod)
360 #ifdef CONFIG_ARM_UNWIND
363 for (i = 0; i < ARM_SEC_MAX; i++)
364 if (mod->arch.unwind[i])
365 unwind_table_del(mod->arch.unwind[i]);