| /* |
| * linux/arch/arm/kernel/module.c |
| * |
| * Copyright (C) 2002 Russell King. |
| * Modified for nommu by Hyok S. Choi |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * Module allocation method suggested by Andi Kleen. |
| */ |
| #include <linux/module.h> |
| #include <linux/moduleloader.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/elf.h> |
| #include <linux/vmalloc.h> |
| #include <linux/fs.h> |
| #include <linux/string.h> |
| #include <linux/gfp.h> |
| |
| #include <asm/pgtable.h> |
| #include <asm/sections.h> |
| #include <asm/unwind.h> |
| |
| #ifdef CONFIG_XIP_KERNEL |
| /* |
| * The XIP kernel text is mapped in the module area for modules and |
| * some other stuff to work without any indirect relocations. |
| * MODULES_VADDR is redefined here and not in asm/memory.h to avoid |
| * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off. |
| */ |
| #undef MODULES_VADDR |
| #define MODULES_VADDR (((unsigned long)_etext + ~PGDIR_MASK) & PGDIR_MASK) |
| #endif |
| |
| #ifdef CONFIG_MMU |
| void *module_alloc(unsigned long size) |
| { |
| return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, |
| GFP_KERNEL, PAGE_KERNEL_EXEC, -1, |
| __builtin_return_address(0)); |
| } |
| #else /* CONFIG_MMU */ |
| void *module_alloc(unsigned long size) |
| { |
| return size == 0 ? NULL : vmalloc(size); |
| } |
| #endif /* !CONFIG_MMU */ |
| |
| void module_free(struct module *module, void *region) |
| { |
| vfree(region); |
| } |
| |
| int module_frob_arch_sections(Elf_Ehdr *hdr, |
| Elf_Shdr *sechdrs, |
| char *secstrings, |
| struct module *mod) |
| { |
| return 0; |
| } |
| |
| int |
| apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex, |
| unsigned int relindex, struct module *module) |
| { |
| Elf32_Shdr *symsec = sechdrs + symindex; |
| Elf32_Shdr *relsec = sechdrs + relindex; |
| Elf32_Shdr *dstsec = sechdrs + relsec->sh_info; |
| Elf32_Rel *rel = (void *)relsec->sh_addr; |
| unsigned int i; |
| |
| for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) { |
| unsigned long loc; |
| Elf32_Sym *sym; |
| s32 offset; |
| #ifdef CONFIG_THUMB2_KERNEL |
| u32 upper, lower, sign, j1, j2; |
| #endif |
| |
| offset = ELF32_R_SYM(rel->r_info); |
| if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) { |
| printk(KERN_ERR "%s: bad relocation, section %d reloc %d\n", |
| module->name, relindex, i); |
| return -ENOEXEC; |
| } |
| |
| sym = ((Elf32_Sym *)symsec->sh_addr) + offset; |
| |
| if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) { |
| printk(KERN_ERR "%s: out of bounds relocation, " |
| "section %d reloc %d offset %d size %d\n", |
| module->name, relindex, i, rel->r_offset, |
| dstsec->sh_size); |
| return -ENOEXEC; |
| } |
| |
| loc = dstsec->sh_addr + rel->r_offset; |
| |
| switch (ELF32_R_TYPE(rel->r_info)) { |
| case R_ARM_NONE: |
| /* ignore */ |
| break; |
| |
| case R_ARM_ABS32: |
| *(u32 *)loc += sym->st_value; |
| break; |
| |
| case R_ARM_PC24: |
| case R_ARM_CALL: |
| case R_ARM_JUMP24: |
| offset = (*(u32 *)loc & 0x00ffffff) << 2; |
| if (offset & 0x02000000) |
| offset -= 0x04000000; |
| |
| offset += sym->st_value - loc; |
| if (offset & 3 || |
| offset <= (s32)0xfe000000 || |
| offset >= (s32)0x02000000) { |
| printk(KERN_ERR |
| "%s: relocation out of range, section " |
| "%d reloc %d sym '%s'\n", module->name, |
| relindex, i, strtab + sym->st_name); |
| return -ENOEXEC; |
| } |
| |
| offset >>= 2; |
| |
| *(u32 *)loc &= 0xff000000; |
| *(u32 *)loc |= offset & 0x00ffffff; |
| break; |
| |
| case R_ARM_V4BX: |
| /* Preserve Rm and the condition code. Alter |
| * other bits to re-code instruction as |
| * MOV PC,Rm. |
| */ |
| *(u32 *)loc &= 0xf000000f; |
| *(u32 *)loc |= 0x01a0f000; |
| break; |
| |
| case R_ARM_PREL31: |
| offset = *(u32 *)loc + sym->st_value - loc; |
| *(u32 *)loc = offset & 0x7fffffff; |
| break; |
| |
| case R_ARM_MOVW_ABS_NC: |
| case R_ARM_MOVT_ABS: |
| offset = *(u32 *)loc; |
| offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff); |
| offset = (offset ^ 0x8000) - 0x8000; |
| |
| offset += sym->st_value; |
| if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS) |
| offset >>= 16; |
| |
| *(u32 *)loc &= 0xfff0f000; |
| *(u32 *)loc |= ((offset & 0xf000) << 4) | |
| (offset & 0x0fff); |
| break; |
| |
| #ifdef CONFIG_THUMB2_KERNEL |
| case R_ARM_THM_CALL: |
| case R_ARM_THM_JUMP24: |
| upper = *(u16 *)loc; |
| lower = *(u16 *)(loc + 2); |
| |
| /* |
| * 25 bit signed address range (Thumb-2 BL and B.W |
| * instructions): |
| * S:I1:I2:imm10:imm11:0 |
| * where: |
| * S = upper[10] = offset[24] |
| * I1 = ~(J1 ^ S) = offset[23] |
| * I2 = ~(J2 ^ S) = offset[22] |
| * imm10 = upper[9:0] = offset[21:12] |
| * imm11 = lower[10:0] = offset[11:1] |
| * J1 = lower[13] |
| * J2 = lower[11] |
| */ |
| sign = (upper >> 10) & 1; |
| j1 = (lower >> 13) & 1; |
| j2 = (lower >> 11) & 1; |
| offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) | |
| ((~(j2 ^ sign) & 1) << 22) | |
| ((upper & 0x03ff) << 12) | |
| ((lower & 0x07ff) << 1); |
| if (offset & 0x01000000) |
| offset -= 0x02000000; |
| offset += sym->st_value - loc; |
| |
| /* only Thumb addresses allowed (no interworking) */ |
| if (!(offset & 1) || |
| offset <= (s32)0xff000000 || |
| offset >= (s32)0x01000000) { |
| printk(KERN_ERR |
| "%s: relocation out of range, section " |
| "%d reloc %d sym '%s'\n", module->name, |
| relindex, i, strtab + sym->st_name); |
| return -ENOEXEC; |
| } |
| |
| sign = (offset >> 24) & 1; |
| j1 = sign ^ (~(offset >> 23) & 1); |
| j2 = sign ^ (~(offset >> 22) & 1); |
| *(u16 *)loc = (u16)((upper & 0xf800) | (sign << 10) | |
| ((offset >> 12) & 0x03ff)); |
| *(u16 *)(loc + 2) = (u16)((lower & 0xd000) | |
| (j1 << 13) | (j2 << 11) | |
| ((offset >> 1) & 0x07ff)); |
| break; |
| |
| case R_ARM_THM_MOVW_ABS_NC: |
| case R_ARM_THM_MOVT_ABS: |
| upper = *(u16 *)loc; |
| lower = *(u16 *)(loc + 2); |
| |
| /* |
| * MOVT/MOVW instructions encoding in Thumb-2: |
| * |
| * i = upper[10] |
| * imm4 = upper[3:0] |
| * imm3 = lower[14:12] |
| * imm8 = lower[7:0] |
| * |
| * imm16 = imm4:i:imm3:imm8 |
| */ |
| offset = ((upper & 0x000f) << 12) | |
| ((upper & 0x0400) << 1) | |
| ((lower & 0x7000) >> 4) | (lower & 0x00ff); |
| offset = (offset ^ 0x8000) - 0x8000; |
| offset += sym->st_value; |
| |
| if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS) |
| offset >>= 16; |
| |
| *(u16 *)loc = (u16)((upper & 0xfbf0) | |
| ((offset & 0xf000) >> 12) | |
| ((offset & 0x0800) >> 1)); |
| *(u16 *)(loc + 2) = (u16)((lower & 0x8f00) | |
| ((offset & 0x0700) << 4) | |
| (offset & 0x00ff)); |
| break; |
| #endif |
| |
| default: |
| printk(KERN_ERR "%s: unknown relocation: %u\n", |
| module->name, ELF32_R_TYPE(rel->r_info)); |
| return -ENOEXEC; |
| } |
| } |
| return 0; |
| } |
| |
| int |
| apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab, |
| unsigned int symindex, unsigned int relsec, struct module *module) |
| { |
| printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n", |
| module->name); |
| return -ENOEXEC; |
| } |
| |
| struct mod_unwind_map { |
| const Elf_Shdr *unw_sec; |
| const Elf_Shdr *txt_sec; |
| }; |
| |
| int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs, |
| struct module *mod) |
| { |
| #ifdef CONFIG_ARM_UNWIND |
| const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; |
| const Elf_Shdr *s, *sechdrs_end = sechdrs + hdr->e_shnum; |
| struct mod_unwind_map maps[ARM_SEC_MAX]; |
| int i; |
| |
| memset(maps, 0, sizeof(maps)); |
| |
| for (s = sechdrs; s < sechdrs_end; s++) { |
| const char *secname = secstrs + s->sh_name; |
| |
| if (!(s->sh_flags & SHF_ALLOC)) |
| continue; |
| |
| if (strcmp(".ARM.exidx.init.text", secname) == 0) |
| maps[ARM_SEC_INIT].unw_sec = s; |
| else if (strcmp(".ARM.exidx.devinit.text", secname) == 0) |
| maps[ARM_SEC_DEVINIT].unw_sec = s; |
| else if (strcmp(".ARM.exidx", secname) == 0) |
| maps[ARM_SEC_CORE].unw_sec = s; |
| else if (strcmp(".ARM.exidx.exit.text", secname) == 0) |
| maps[ARM_SEC_EXIT].unw_sec = s; |
| else if (strcmp(".ARM.exidx.devexit.text", secname) == 0) |
| maps[ARM_SEC_DEVEXIT].unw_sec = s; |
| else if (strcmp(".init.text", secname) == 0) |
| maps[ARM_SEC_INIT].txt_sec = s; |
| else if (strcmp(".devinit.text", secname) == 0) |
| maps[ARM_SEC_DEVINIT].txt_sec = s; |
| else if (strcmp(".text", secname) == 0) |
| maps[ARM_SEC_CORE].txt_sec = s; |
| else if (strcmp(".exit.text", secname) == 0) |
| maps[ARM_SEC_EXIT].txt_sec = s; |
| else if (strcmp(".devexit.text", secname) == 0) |
| maps[ARM_SEC_DEVEXIT].txt_sec = s; |
| } |
| |
| for (i = 0; i < ARM_SEC_MAX; i++) |
| if (maps[i].unw_sec && maps[i].txt_sec) |
| mod->arch.unwind[i] = |
| unwind_table_add(maps[i].unw_sec->sh_addr, |
| maps[i].unw_sec->sh_size, |
| maps[i].txt_sec->sh_addr, |
| maps[i].txt_sec->sh_size); |
| #endif |
| return 0; |
| } |
| |
| void |
| module_arch_cleanup(struct module *mod) |
| { |
| #ifdef CONFIG_ARM_UNWIND |
| int i; |
| |
| for (i = 0; i < ARM_SEC_MAX; i++) |
| if (mod->arch.unwind[i]) |
| unwind_table_del(mod->arch.unwind[i]); |
| #endif |
| } |