diff options
Diffstat (limited to 'arch/s390/kernel/module.c')
| -rw-r--r-- | arch/s390/kernel/module.c | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c new file mode 100644 index 00000000000..607d506689c --- /dev/null +++ b/arch/s390/kernel/module.c @@ -0,0 +1,405 @@ +/* + * arch/s390/kernel/module.c - Kernel module help for s390. + * + * S390 version + * Copyright (C) 2002, 2003 IBM Deutschland Entwicklung GmbH, + * IBM Corporation + * Author(s): Arnd Bergmann (arndb@de.ibm.com) + * Martin Schwidefsky (schwidefsky@de.ibm.com) + * + * based on i386 version + * Copyright (C) 2001 Rusty Russell. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <linux/module.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <linux/kernel.h> + +#if 0 +#define DEBUGP printk +#else +#define DEBUGP(fmt , ...) +#endif + +#ifndef CONFIG_ARCH_S390X +#define PLT_ENTRY_SIZE 12 +#else /* CONFIG_ARCH_S390X */ +#define PLT_ENTRY_SIZE 20 +#endif /* CONFIG_ARCH_S390X */ + +void *module_alloc(unsigned long size) +{ + if (size == 0) + return NULL; + return vmalloc(size); +} + +/* Free memory returned from module_alloc */ +void module_free(struct module *mod, void *module_region) +{ + vfree(module_region); + /* FIXME: If module_region == mod->init_region, trim exception + table entries. */ +} + +static inline void +check_rela(Elf_Rela *rela, struct module *me) +{ + struct mod_arch_syminfo *info; + + info = me->arch.syminfo + ELF_R_SYM (rela->r_info); + switch (ELF_R_TYPE (rela->r_info)) { + case R_390_GOT12: /* 12 bit GOT offset. */ + case R_390_GOT16: /* 16 bit GOT offset. */ + case R_390_GOT20: /* 20 bit GOT offset. */ + case R_390_GOT32: /* 32 bit GOT offset. */ + case R_390_GOT64: /* 64 bit GOT offset. */ + case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */ + case R_390_GOTPLT12: /* 12 bit offset to jump slot. */ + case R_390_GOTPLT16: /* 16 bit offset to jump slot. */ + case R_390_GOTPLT20: /* 20 bit offset to jump slot. */ + case R_390_GOTPLT32: /* 32 bit offset to jump slot. */ + case R_390_GOTPLT64: /* 64 bit offset to jump slot. */ + case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */ + if (info->got_offset == -1UL) { + info->got_offset = me->arch.got_size; + me->arch.got_size += sizeof(void*); + } + break; + case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */ + case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */ + case R_390_PLT32: /* 32 bit PC relative PLT address. */ + case R_390_PLT64: /* 64 bit PC relative PLT address. */ + case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */ + case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */ + case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */ + if (info->plt_offset == -1UL) { + info->plt_offset = me->arch.plt_size; + me->arch.plt_size += PLT_ENTRY_SIZE; + } + break; + case R_390_COPY: + case R_390_GLOB_DAT: + case R_390_JMP_SLOT: + case R_390_RELATIVE: + /* Only needed if we want to support loading of + modules linked with -shared. */ + break; + } +} + +/* + * Account for GOT and PLT relocations. We can't add sections for + * got and plt but we can increase the core module size. + */ +int +module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, + char *secstrings, struct module *me) +{ + Elf_Shdr *symtab; + Elf_Sym *symbols; + Elf_Rela *rela; + char *strings; + int nrela, i, j; + + /* Find symbol table and string table. */ + symtab = 0; + for (i = 0; i < hdr->e_shnum; i++) + switch (sechdrs[i].sh_type) { + case SHT_SYMTAB: + symtab = sechdrs + i; + break; + } + if (!symtab) { + printk(KERN_ERR "module %s: no symbol table\n", me->name); + return -ENOEXEC; + } + + /* Allocate one syminfo structure per symbol. */ + me->arch.nsyms = symtab->sh_size / sizeof(Elf_Sym); + me->arch.syminfo = vmalloc(me->arch.nsyms * + sizeof(struct mod_arch_syminfo)); + if (!me->arch.syminfo) + return -ENOMEM; + symbols = (void *) hdr + symtab->sh_offset; + strings = (void *) hdr + sechdrs[symtab->sh_link].sh_offset; + for (i = 0; i < me->arch.nsyms; i++) { + if (symbols[i].st_shndx == SHN_UNDEF && + strcmp(strings + symbols[i].st_name, + "_GLOBAL_OFFSET_TABLE_") == 0) + /* "Define" it as absolute. */ + symbols[i].st_shndx = SHN_ABS; + me->arch.syminfo[i].got_offset = -1UL; + me->arch.syminfo[i].plt_offset = -1UL; + me->arch.syminfo[i].got_initialized = 0; + me->arch.syminfo[i].plt_initialized = 0; + } + + /* Search for got/plt relocations. */ + me->arch.got_size = me->arch.plt_size = 0; + for (i = 0; i < hdr->e_shnum; i++) { + if (sechdrs[i].sh_type != SHT_RELA) + continue; + nrela = sechdrs[i].sh_size / sizeof(Elf_Rela); + rela = (void *) hdr + sechdrs[i].sh_offset; + for (j = 0; j < nrela; j++) + check_rela(rela + j, me); + } + + /* Increase core size by size of got & plt and set start + offsets for got and plt. */ + me->core_size = ALIGN(me->core_size, 4); + me->arch.got_offset = me->core_size; + me->core_size += me->arch.got_size; + me->arch.plt_offset = me->core_size; + me->core_size += me->arch.plt_size; + return 0; +} + +int +apply_relocate(Elf_Shdr *sechdrs, const char *strtab, unsigned int symindex, + unsigned int relsec, struct module *me) +{ + printk(KERN_ERR "module %s: RELOCATION unsupported\n", + me->name); + return -ENOEXEC; +} + +static inline int +apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab, + struct module *me) +{ + struct mod_arch_syminfo *info; + Elf_Addr loc, val; + int r_type, r_sym; + + /* This is where to make the change */ + loc = base + rela->r_offset; + /* This is the symbol it is referring to. Note that all + undefined symbols have been resolved. */ + r_sym = ELF_R_SYM(rela->r_info); + r_type = ELF_R_TYPE(rela->r_info); + info = me->arch.syminfo + r_sym; + val = symtab[r_sym].st_value; + + switch (r_type) { + case R_390_8: /* Direct 8 bit. */ + case R_390_12: /* Direct 12 bit. */ + case R_390_16: /* Direct 16 bit. */ + case R_390_20: /* Direct 20 bit. */ + case R_390_32: /* Direct 32 bit. */ + case R_390_64: /* Direct 64 bit. */ + val += rela->r_addend; + if (r_type == R_390_8) + *(unsigned char *) loc = val; + else if (r_type == R_390_12) + *(unsigned short *) loc = (val & 0xfff) | + (*(unsigned short *) loc & 0xf000); + else if (r_type == R_390_16) + *(unsigned short *) loc = val; + else if (r_type == R_390_20) + *(unsigned int *) loc = + (*(unsigned int *) loc & 0xf00000ff) | + (val & 0xfff) << 16 | (val & 0xff000) >> 4; + else if (r_type == R_390_32) + *(unsigned int *) loc = val; + else if (r_type == R_390_64) + *(unsigned long *) loc = val; + break; + case R_390_PC16: /* PC relative 16 bit. */ + case R_390_PC16DBL: /* PC relative 16 bit shifted by 1. */ + case R_390_PC32DBL: /* PC relative 32 bit shifted by 1. */ + case R_390_PC32: /* PC relative 32 bit. */ + case R_390_PC64: /* PC relative 64 bit. */ + val += rela->r_addend - loc; + if (r_type == R_390_PC16) + *(unsigned short *) loc = val; + else if (r_type == R_390_PC16DBL) + *(unsigned short *) loc = val >> 1; + else if (r_type == R_390_PC32DBL) + *(unsigned int *) loc = val >> 1; + else if (r_type == R_390_PC32) + *(unsigned int *) loc = val; + else if (r_type == R_390_PC64) + *(unsigned long *) loc = val; + break; + case R_390_GOT12: /* 12 bit GOT offset. */ + case R_390_GOT16: /* 16 bit GOT offset. */ + case R_390_GOT20: /* 20 bit GOT offset. */ + case R_390_GOT32: /* 32 bit GOT offset. */ + case R_390_GOT64: /* 64 bit GOT offset. */ + case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */ + case R_390_GOTPLT12: /* 12 bit offset to jump slot. */ + case R_390_GOTPLT20: /* 20 bit offset to jump slot. */ + case R_390_GOTPLT16: /* 16 bit offset to jump slot. */ + case R_390_GOTPLT32: /* 32 bit offset to jump slot. */ + case R_390_GOTPLT64: /* 64 bit offset to jump slot. */ + case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */ + if (info->got_initialized == 0) { + Elf_Addr *gotent; + + gotent = me->module_core + me->arch.got_offset + + info->got_offset; + *gotent = val; + info->got_initialized = 1; + } + val = info->got_offset + rela->r_addend; + if (r_type == R_390_GOT12 || + r_type == R_390_GOTPLT12) + *(unsigned short *) loc = (val & 0xfff) | + (*(unsigned short *) loc & 0xf000); + else if (r_type == R_390_GOT16 || + r_type == R_390_GOTPLT16) + *(unsigned short *) loc = val; + else if (r_type == R_390_GOT20 || + r_type == R_390_GOTPLT20) + *(unsigned int *) loc = + (*(unsigned int *) loc & 0xf00000ff) | + (val & 0xfff) << 16 | (val & 0xff000) >> 4; + else if (r_type == R_390_GOT32 || + r_type == R_390_GOTPLT32) + *(unsigned int *) loc = val; + else if (r_type == R_390_GOTENT || + r_type == R_390_GOTPLTENT) + *(unsigned int *) loc = + (val + (Elf_Addr) me->module_core - loc) >> 1; + else if (r_type == R_390_GOT64 || + r_type == R_390_GOTPLT64) + *(unsigned long *) loc = val; + break; + case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */ + case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */ + case R_390_PLT32: /* 32 bit PC relative PLT address. */ + case R_390_PLT64: /* 64 bit PC relative PLT address. */ + case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */ + case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */ + case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */ + if (info->plt_initialized == 0) { + unsigned int *ip; + ip = me->module_core + me->arch.plt_offset + + info->plt_offset; +#ifndef CONFIG_ARCH_S390X + ip[0] = 0x0d105810; /* basr 1,0; l 1,6(1); br 1 */ + ip[1] = 0x100607f1; + ip[2] = val; +#else /* CONFIG_ARCH_S390X */ + ip[0] = 0x0d10e310; /* basr 1,0; lg 1,10(1); br 1 */ + ip[1] = 0x100a0004; + ip[2] = 0x07f10000; + ip[3] = (unsigned int) (val >> 32); + ip[4] = (unsigned int) val; +#endif /* CONFIG_ARCH_S390X */ + info->plt_initialized = 1; + } + if (r_type == R_390_PLTOFF16 || + r_type == R_390_PLTOFF32 + || r_type == R_390_PLTOFF64 + ) + val = me->arch.plt_offset - me->arch.got_offset + + info->plt_offset + rela->r_addend; + else + val = (Elf_Addr) me->module_core + + me->arch.plt_offset + info->plt_offset + + rela->r_addend - loc; + if (r_type == R_390_PLT16DBL) + *(unsigned short *) loc = val >> 1; + else if (r_type == R_390_PLTOFF16) + *(unsigned short *) loc = val; + else if (r_type == R_390_PLT32DBL) + *(unsigned int *) loc = val >> 1; + else if (r_type == R_390_PLT32 || + r_type == R_390_PLTOFF32) + *(unsigned int *) loc = val; + else if (r_type == R_390_PLT64 || + r_type == R_390_PLTOFF64) + *(unsigned long *) loc = val; + break; + case R_390_GOTOFF16: /* 16 bit offset to GOT. */ + case R_390_GOTOFF32: /* 32 bit offset to GOT. */ + case R_390_GOTOFF64: /* 64 bit offset to GOT. */ + val = val + rela->r_addend - + ((Elf_Addr) me->module_core + me->arch.got_offset); + if (r_type == R_390_GOTOFF16) + *(unsigned short *) loc = val; + else if (r_type == R_390_GOTOFF32) + *(unsigned int *) loc = val; + else if (r_type == R_390_GOTOFF64) + *(unsigned long *) loc = val; + break; + case R_390_GOTPC: /* 32 bit PC relative offset to GOT. */ + case R_390_GOTPCDBL: /* 32 bit PC rel. off. to GOT shifted by 1. */ + val = (Elf_Addr) me->module_core + me->arch.got_offset + + rela->r_addend - loc; + if (r_type == R_390_GOTPC) + *(unsigned int *) loc = val; + else if (r_type == R_390_GOTPCDBL) + *(unsigned int *) loc = val >> 1; + break; + case R_390_COPY: + case R_390_GLOB_DAT: /* Create GOT entry. */ + case R_390_JMP_SLOT: /* Create PLT entry. */ + case R_390_RELATIVE: /* Adjust by program base. */ + /* Only needed if we want to support loading of + modules linked with -shared. */ + break; + default: + printk(KERN_ERR "module %s: Unknown relocation: %u\n", + me->name, r_type); + return -ENOEXEC; + } + return 0; +} + +int +apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *me) +{ + Elf_Addr base; + Elf_Sym *symtab; + Elf_Rela *rela; + unsigned long i, n; + int rc; + + DEBUGP("Applying relocate section %u to %u\n", + relsec, sechdrs[relsec].sh_info); + base = sechdrs[sechdrs[relsec].sh_info].sh_addr; + symtab = (Elf_Sym *) sechdrs[symindex].sh_addr; + rela = (Elf_Rela *) sechdrs[relsec].sh_addr; + n = sechdrs[relsec].sh_size / sizeof(Elf_Rela); + + for (i = 0; i < n; i++, rela++) { + rc = apply_rela(rela, base, symtab, me); + if (rc) + return rc; + } + return 0; +} + +int module_finalize(const Elf_Ehdr *hdr, + const Elf_Shdr *sechdrs, + struct module *me) +{ + vfree(me->arch.syminfo); + return 0; +} + +void module_arch_cleanup(struct module *mod) +{ +} |