module.c

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/*
 * 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.
 */

#include <linux/moduleloader.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

#ifdef CONFIG_MODULES

int apply_relocate(Elf32_Shdr *sechdrs,
           const char *strtab,
           unsigned int symindex,
           unsigned int relsec,
           struct module *me)
{
    unsigned int i;
    Elf32_Rel *rel = (void *)sechdrs[relsec].sh_addr;
    Elf32_Sym *sym;
    uint32_t *location;

    DEBUGP("Applying relocate section %u to %u\n", relsec,
           sechdrs[relsec].sh_info);
    for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
        /* This is where to make the change */
        location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
            + rel[i].r_offset;
        /* This is the symbol it is referring to.  Note that all
           undefined symbols have been resolved.  */
        sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
            + ELF32_R_SYM(rel[i].r_info);

        switch (ELF32_R_TYPE(rel[i].r_info)) {
        case R_68K_32:
            /* We add the value into the location given */
            *location += sym->st_value;
            break;
        case R_68K_PC32:
            /* Add the value, subtract its position */
            *location += sym->st_value - (uint32_t)location;
            break;
        default:
            printk(KERN_ERR "module %s: Unknown relocation: %u\n",
                   me->name, ELF32_R_TYPE(rel[i].r_info));
            return -ENOEXEC;
        }
    }
    return 0;
}

int apply_relocate_add(Elf32_Shdr *sechdrs,
               const char *strtab,
               unsigned int symindex,
               unsigned int relsec,
               struct module *me)
{
    unsigned int i;
    Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
    Elf32_Sym *sym;
    uint32_t *location;

    DEBUGP("Applying relocate_add section %u to %u\n", relsec,
           sechdrs[relsec].sh_info);
    for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
        /* This is where to make the change */
        location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
            + rel[i].r_offset;
        /* This is the symbol it is referring to.  Note that all
           undefined symbols have been resolved.  */
        sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
            + ELF32_R_SYM(rel[i].r_info);

        switch (ELF32_R_TYPE(rel[i].r_info)) {
        case R_68K_32:
            /* We add the value into the location given */
            *location = rel[i].r_addend + sym->st_value;
            break;
        case R_68K_PC32:
            /* Add the value, subtract its position */
            *location = rel[i].r_addend + sym->st_value - (uint32_t)location;
            break;
        default:
            printk(KERN_ERR "module %s: Unknown relocation: %u\n",
                   me->name, ELF32_R_TYPE(rel[i].r_info));
            return -ENOEXEC;
        }
    }
    return 0;
}

int module_finalize(const Elf_Ehdr *hdr,
            const Elf_Shdr *sechdrs,
            struct module *mod)
{
    module_fixup(mod, mod->arch.fixup_start, mod->arch.fixup_end);
    return 0;
}

#endif /* CONFIG_MODULES */

void module_fixup(struct module *mod, struct m68k_fixup_info *start,
          struct m68k_fixup_info *end)
{
#ifdef CONFIG_MMU
    struct m68k_fixup_info *fixup;

    for (fixup = start; fixup < end; fixup++) {
        switch (fixup->type) {
        case m68k_fixup_memoffset:
            *(u32 *)fixup->addr = m68k_memoffset;
            break;
        case m68k_fixup_vnode_shift:
            *(u16 *)fixup->addr += m68k_virt_to_node_shift;
            break;
        }
    }
#endif
}