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Diffstat (limited to '')
| -rw-r--r-- | arch/xtensa/kernel/module.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/arch/xtensa/kernel/module.c b/arch/xtensa/kernel/module.c new file mode 100644 index 000000000..902845dda --- /dev/null +++ b/arch/xtensa/kernel/module.c @@ -0,0 +1,189 @@ +/* + * arch/xtensa/kernel/module.c + * + * Module support. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2001 - 2006 Tensilica Inc. + * + * Chris Zankel <chris@zankel.net> + * + */ + +#include <linux/module.h> +#include <linux/moduleloader.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <linux/cache.h> + +static int +decode_calln_opcode (unsigned char *location) +{ +#ifdef __XTENSA_EB__ + return (location[0] & 0xf0) == 0x50; +#endif +#ifdef __XTENSA_EL__ + return (location[0] & 0xf) == 0x5; +#endif +} + +static int +decode_l32r_opcode (unsigned char *location) +{ +#ifdef __XTENSA_EB__ + return (location[0] & 0xf0) == 0x10; +#endif +#ifdef __XTENSA_EL__ + return (location[0] & 0xf) == 0x1; +#endif +} + +int apply_relocate_add(Elf32_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *mod) +{ + unsigned int i; + Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr; + Elf32_Sym *sym; + unsigned char *location; + uint32_t value; + + pr_debug("Applying relocate section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) { + location = (char *)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rela[i].r_offset; + sym = (Elf32_Sym *)sechdrs[symindex].sh_addr + + ELF32_R_SYM(rela[i].r_info); + value = sym->st_value + rela[i].r_addend; + + switch (ELF32_R_TYPE(rela[i].r_info)) { + case R_XTENSA_NONE: + case R_XTENSA_DIFF8: + case R_XTENSA_DIFF16: + case R_XTENSA_DIFF32: + case R_XTENSA_ASM_EXPAND: + break; + + case R_XTENSA_32: + case R_XTENSA_PLT: + *(uint32_t *)location += value; + break; + + case R_XTENSA_SLOT0_OP: + if (decode_calln_opcode(location)) { + value -= ((unsigned long)location & -4) + 4; + if ((value & 3) != 0 || + ((value + (1 << 19)) >> 20) != 0) { + pr_err("%s: relocation out of range, " + "section %d reloc %d " + "sym '%s'\n", + mod->name, relsec, i, + strtab + sym->st_name); + return -ENOEXEC; + } + value = (signed int)value >> 2; +#ifdef __XTENSA_EB__ + location[0] = ((location[0] & ~0x3) | + ((value >> 16) & 0x3)); + location[1] = (value >> 8) & 0xff; + location[2] = value & 0xff; +#endif +#ifdef __XTENSA_EL__ + location[0] = ((location[0] & ~0xc0) | + ((value << 6) & 0xc0)); + location[1] = (value >> 2) & 0xff; + location[2] = (value >> 10) & 0xff; +#endif + } else if (decode_l32r_opcode(location)) { + value -= (((unsigned long)location + 3) & -4); + if ((value & 3) != 0 || + (signed int)value >> 18 != -1) { + pr_err("%s: relocation out of range, " + "section %d reloc %d " + "sym '%s'\n", + mod->name, relsec, i, + strtab + sym->st_name); + return -ENOEXEC; + } + value = (signed int)value >> 2; + +#ifdef __XTENSA_EB__ + location[1] = (value >> 8) & 0xff; + location[2] = value & 0xff; +#endif +#ifdef __XTENSA_EL__ + location[1] = value & 0xff; + location[2] = (value >> 8) & 0xff; +#endif + } + /* FIXME: Ignore any other opcodes. The Xtensa + assembler currently assumes that the linker will + always do relaxation and so all PC-relative + operands need relocations. (The assembler also + writes out the tentative PC-relative values, + assuming no link-time relaxation, so it is usually + safe to ignore the relocations.) If the + assembler's "--no-link-relax" flag can be made to + work, and if all kernel modules can be assembled + with that flag, then unexpected relocations could + be detected here. */ + break; + + case R_XTENSA_SLOT1_OP: + case R_XTENSA_SLOT2_OP: + case R_XTENSA_SLOT3_OP: + case R_XTENSA_SLOT4_OP: + case R_XTENSA_SLOT5_OP: + case R_XTENSA_SLOT6_OP: + case R_XTENSA_SLOT7_OP: + case R_XTENSA_SLOT8_OP: + case R_XTENSA_SLOT9_OP: + case R_XTENSA_SLOT10_OP: + case R_XTENSA_SLOT11_OP: + case R_XTENSA_SLOT12_OP: + case R_XTENSA_SLOT13_OP: + case R_XTENSA_SLOT14_OP: + pr_err("%s: unexpected FLIX relocation: %u\n", + mod->name, + ELF32_R_TYPE(rela[i].r_info)); + return -ENOEXEC; + + case R_XTENSA_SLOT0_ALT: + case R_XTENSA_SLOT1_ALT: + case R_XTENSA_SLOT2_ALT: + case R_XTENSA_SLOT3_ALT: + case R_XTENSA_SLOT4_ALT: + case R_XTENSA_SLOT5_ALT: + case R_XTENSA_SLOT6_ALT: + case R_XTENSA_SLOT7_ALT: + case R_XTENSA_SLOT8_ALT: + case R_XTENSA_SLOT9_ALT: + case R_XTENSA_SLOT10_ALT: + case R_XTENSA_SLOT11_ALT: + case R_XTENSA_SLOT12_ALT: + case R_XTENSA_SLOT13_ALT: + case R_XTENSA_SLOT14_ALT: + pr_err("%s: unexpected ALT relocation: %u\n", + mod->name, + ELF32_R_TYPE(rela[i].r_info)); + return -ENOEXEC; + + default: + pr_err("%s: unexpected relocation: %u\n", + mod->name, + ELF32_R_TYPE(rela[i].r_info)); + return -ENOEXEC; + } + } + return 0; +} |