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-rw-r--r--arch/mips/kernel/module-elf64.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/arch/mips/kernel/module-elf64.c b/arch/mips/kernel/module-elf64.c
new file mode 100644
index 000000000000..e804792ee1ee
--- /dev/null
+++ b/arch/mips/kernel/module-elf64.c
@@ -0,0 +1,274 @@
+/*
+ * 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
+ *
+ * Copyright (C) 2001 Rusty Russell.
+ * Copyright (C) 2003, 2004 Ralf Baechle (ralf@linux-mips.org)
+ */
+
+#undef DEBUG
+
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+
+struct mips_hi16 {
+ struct mips_hi16 *next;
+ Elf32_Addr *addr;
+ Elf64_Addr value;
+};
+
+static struct mips_hi16 *mips_hi16_list;
+
+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. */
+}
+
+int module_frob_arch_sections(Elf_Ehdr *hdr,
+ Elf_Shdr *sechdrs,
+ char *secstrings,
+ struct module *mod)
+{
+ return 0;
+}
+
+int apply_relocate(Elf64_Shdr *sechdrs,
+ const char *strtab,
+ unsigned int symindex,
+ unsigned int relsec,
+ struct module *me)
+{
+ /*
+ * We don't want to deal with REL relocations - RELA is so much saner.
+ */
+ if (!sechdrs[relsec].sh_size)
+ return 0;
+
+ printk(KERN_ERR "module %s: REL relocation unsupported\n",
+ me->name);
+ return -ENOEXEC;
+}
+
+static int apply_r_mips_none(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ return 0;
+}
+
+static int apply_r_mips_32(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ *location = v;
+
+ return 0;
+}
+
+static int apply_r_mips_26(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ if (v % 4) {
+ printk(KERN_ERR "module %s: dangerous relocation\n", me->name);
+ return -ENOEXEC;
+ }
+
+ if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
+ printk(KERN_ERR
+ "module %s: relocation overflow\n",
+ me->name);
+ return -ENOEXEC;
+ }
+
+ *location = (*location & ~0x03ffffff) | ((v >> 2) & 0x03ffffff);
+
+ return 0;
+}
+
+static int apply_r_mips_hi16(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ struct mips_hi16 *n;
+
+ /*
+ * We cannot relocate this one now because we don't know the value of
+ * the carry we need to add. Save the information, and let LO16 do the
+ * actual relocation.
+ */
+ n = kmalloc(sizeof *n, GFP_KERNEL);
+ if (!n)
+ return -ENOMEM;
+
+ n->addr = location;
+ n->value = v;
+ n->next = mips_hi16_list;
+ mips_hi16_list = n;
+
+ return 0;
+}
+
+static int apply_r_mips_lo16(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ unsigned long insnlo = *location;
+ Elf32_Addr val, vallo;
+
+ /* Sign extend the addend we extract from the lo insn. */
+ vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
+
+ if (mips_hi16_list != NULL) {
+ struct mips_hi16 *l;
+
+ l = mips_hi16_list;
+ while (l != NULL) {
+ struct mips_hi16 *next;
+ unsigned long insn;
+
+ /*
+ * The value for the HI16 had best be the same.
+ */
+ if (v != l->value)
+ goto out_danger;
+
+ /*
+ * Do the HI16 relocation. Note that we actually don't
+ * need to know anything about the LO16 itself, except
+ * where to find the low 16 bits of the addend needed
+ * by the LO16.
+ */
+ insn = *l->addr;
+ val = ((insn & 0xffff) << 16) + vallo;
+ val += v;
+
+ /*
+ * Account for the sign extension that will happen in
+ * the low bits.
+ */
+ val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
+
+ insn = (insn & ~0xffff) | val;
+ *l->addr = insn;
+
+ next = l->next;
+ kfree(l);
+ l = next;
+ }
+
+ mips_hi16_list = NULL;
+ }
+
+ /*
+ * Ok, we're done with the HI16 relocs. Now deal with the LO16.
+ */
+ insnlo = (insnlo & ~0xffff) | (v & 0xffff);
+ *location = insnlo;
+
+ return 0;
+
+out_danger:
+ printk(KERN_ERR "module %s: dangerous " "relocation\n", me->name);
+
+ return -ENOEXEC;
+}
+
+static int apply_r_mips_64(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ *(uint64_t *) location = v;
+
+ return 0;
+}
+
+
+static int apply_r_mips_higher(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ *location = (*location & 0xffff0000) |
+ ((((long long) v + 0x80008000LL) >> 32) & 0xffff);
+
+ return 0;
+}
+
+static int apply_r_mips_highest(struct module *me, uint32_t *location,
+ Elf64_Addr v)
+{
+ *location = (*location & 0xffff0000) |
+ ((((long long) v + 0x800080008000LL) >> 48) & 0xffff);
+
+ return 0;
+}
+
+static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
+ Elf64_Addr v) = {
+ [R_MIPS_NONE] = apply_r_mips_none,
+ [R_MIPS_32] = apply_r_mips_32,
+ [R_MIPS_26] = apply_r_mips_26,
+ [R_MIPS_HI16] = apply_r_mips_hi16,
+ [R_MIPS_LO16] = apply_r_mips_lo16,
+ [R_MIPS_64] = apply_r_mips_64,
+ [R_MIPS_HIGHER] = apply_r_mips_higher,
+ [R_MIPS_HIGHEST] = apply_r_mips_highest
+};
+
+int apply_relocate_add(Elf64_Shdr *sechdrs,
+ const char *strtab,
+ unsigned int symindex,
+ unsigned int relsec,
+ struct module *me)
+{
+ Elf64_Mips_Rela *rel = (void *) sechdrs[relsec].sh_addr;
+ Elf64_Sym *sym;
+ uint32_t *location;
+ unsigned int i;
+ Elf64_Addr v;
+ int res;
+
+ pr_debug("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 */
+ sym = (Elf64_Sym *)sechdrs[symindex].sh_addr + rel[i].r_sym;
+ if (!sym->st_value) {
+ printk(KERN_WARNING "%s: Unknown symbol %s\n",
+ me->name, strtab + sym->st_name);
+ return -ENOENT;
+ }
+
+ v = sym->st_value;
+
+ res = reloc_handlers[rel[i].r_type](me, location, v);
+ if (res)
+ return res;
+ }
+
+ return 0;
+}