From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- arch/arm/kernel/module.c | 367 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 367 insertions(+) create mode 100644 arch/arm/kernel/module.c (limited to 'arch/arm/kernel/module.c') diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c new file mode 100644 index 00000000..016d6a08 --- /dev/null +++ b/arch/arm/kernel/module.c @@ -0,0 +1,367 @@ +/* + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#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; + const char *symname; + 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))) { + pr_err("%s: section %u reloc %u: bad relocation sym offset\n", + module->name, relindex, i); + return -ENOEXEC; + } + + sym = ((Elf32_Sym *)symsec->sh_addr) + offset; + symname = strtab + sym->st_name; + + if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) { + pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n", + module->name, relindex, i, symname, + 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) { + pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n", + module->name, relindex, i, symname, + ELF32_R_TYPE(rel->r_info), loc, + sym->st_value); + 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; + + /* + * For function symbols, only Thumb addresses are + * allowed (no interworking). + * + * For non-function symbols, the destination + * has no specific ARM/Thumb disposition, so + * the branch is resolved under the assumption + * that interworking is not required. + */ + if ((ELF32_ST_TYPE(sym->st_info) == STT_FUNC && + !(offset & 1)) || + offset <= (s32)0xff000000 || + offset >= (s32)0x01000000) { + pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n", + module->name, relindex, i, symname, + ELF32_R_TYPE(rel->r_info), loc, + sym->st_value); + 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; +}; + +static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr, + const Elf_Shdr *sechdrs, const char *name) +{ + const Elf_Shdr *s, *se; + const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + + for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) + if (strcmp(name, secstrs + s->sh_name) == 0) + return s; + + return NULL; +} + +extern void fixup_pv_table(const void *, unsigned long); +extern void fixup_smp(const void *, unsigned long); + +int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs, + struct module *mod) +{ + const Elf_Shdr *s = NULL; +#ifdef CONFIG_ARM_UNWIND + const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + const Elf_Shdr *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 +#ifdef CONFIG_ARM_PATCH_PHYS_VIRT + s = find_mod_section(hdr, sechdrs, ".pv_table"); + if (s) + fixup_pv_table((void *)s->sh_addr, s->sh_size); +#endif + s = find_mod_section(hdr, sechdrs, ".alt.smp.init"); + if (s && !is_smp()) + fixup_smp((void *)s->sh_addr, s->sh_size); + 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 +} -- cgit v1.2.3