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-rw-r--r--grub-core/kern/mips/dl.c239
1 files changed, 239 insertions, 0 deletions
diff --git a/grub-core/kern/mips/dl.c b/grub-core/kern/mips/dl.c
new file mode 100644
index 0000000..e17e9f3
--- /dev/null
+++ b/grub-core/kern/mips/dl.c
@@ -0,0 +1,239 @@
+/* dl-386.c - arch-dependent part of loadable module support */
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2002,2005,2007,2009 Free Software Foundation, Inc.
+ *
+ * GRUB 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/dl.h>
+#include <grub/elf.h>
+#include <grub/misc.h>
+#include <grub/err.h>
+#include <grub/cpu/types.h>
+#include <grub/mm.h>
+
+/* Dummy __gnu_local_gp. Resolved by linker. */
+static char __gnu_local_gp_dummy;
+
+/* Check if EHDR is a valid ELF header. */
+grub_err_t
+grub_arch_dl_check_header (void *ehdr)
+{
+ Elf_Ehdr *e = ehdr;
+
+ /* Check the magic numbers. */
+#ifdef WORDS_BIGENDIAN
+ if (e->e_ident[EI_CLASS] != ELFCLASS32
+ || e->e_ident[EI_DATA] != ELFDATA2MSB
+ || e->e_machine != EM_MIPS)
+#else
+ if (e->e_ident[EI_CLASS] != ELFCLASS32
+ || e->e_ident[EI_DATA] != ELFDATA2LSB
+ || e->e_machine != EM_MIPS)
+#endif
+ return grub_error (GRUB_ERR_BAD_OS, "invalid arch specific ELF magic");
+
+ return GRUB_ERR_NONE;
+}
+
+/* Relocate symbols. */
+grub_err_t
+grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr)
+{
+ Elf_Ehdr *e = ehdr;
+ Elf_Shdr *s;
+ Elf_Word entsize;
+ unsigned i;
+ grub_size_t gp_size = 0;
+ /* FIXME: suboptimal. */
+ grub_uint32_t *gp, *gpptr;
+ grub_uint32_t gp0;
+
+ /* Find a symbol table. */
+ for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
+ i < e->e_shnum;
+ i++, s = (Elf_Shdr *) ((char *) s + e->e_shentsize))
+ if (s->sh_type == SHT_SYMTAB)
+ break;
+
+ if (i == e->e_shnum)
+ return grub_error (GRUB_ERR_BAD_MODULE, "no symtab found");
+
+ entsize = s->sh_entsize;
+
+ /* Find reginfo. */
+ for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
+ i < e->e_shnum;
+ i++, s = (Elf_Shdr *) ((char *) s + e->e_shentsize))
+ if (s->sh_type == SHT_MIPS_REGINFO)
+ break;
+
+ if (i == e->e_shnum)
+ return grub_error (GRUB_ERR_BAD_MODULE, "no reginfo found");
+
+ gp0 = ((grub_uint32_t *)((char *) e + s->sh_offset))[5];
+
+ for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
+ i < e->e_shnum;
+ i++, s = (Elf_Shdr *) ((char *) s + e->e_shentsize))
+ if (s->sh_type == SHT_REL)
+ {
+ grub_dl_segment_t seg;
+
+ /* Find the target segment. */
+ for (seg = mod->segment; seg; seg = seg->next)
+ if (seg->section == s->sh_info)
+ break;
+
+ if (seg)
+ {
+ Elf_Rel *rel, *max;
+
+ for (rel = (Elf_Rel *) ((char *) e + s->sh_offset),
+ max = rel + s->sh_size / s->sh_entsize;
+ rel < max;
+ rel++)
+ switch (ELF_R_TYPE (rel->r_info))
+ {
+ case R_MIPS_GOT16:
+ case R_MIPS_CALL16:
+ case R_MIPS_GPREL32:
+ gp_size += 4;
+ break;
+ }
+ }
+ }
+
+ if (gp_size > 0x08000)
+ return grub_error (GRUB_ERR_OUT_OF_RANGE, "__gnu_local_gp is too big\n");
+
+ gpptr = gp = grub_malloc (gp_size);
+ if (!gp)
+ return grub_errno;
+
+ for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
+ i < e->e_shnum;
+ i++, s = (Elf_Shdr *) ((char *) s + e->e_shentsize))
+ if (s->sh_type == SHT_REL)
+ {
+ grub_dl_segment_t seg;
+
+ /* Find the target segment. */
+ for (seg = mod->segment; seg; seg = seg->next)
+ if (seg->section == s->sh_info)
+ break;
+
+ if (seg)
+ {
+ Elf_Rel *rel, *max;
+
+ for (rel = (Elf_Rel *) ((char *) e + s->sh_offset),
+ max = rel + s->sh_size / s->sh_entsize;
+ rel < max;
+ rel++)
+ {
+ Elf_Word *addr;
+ Elf_Sym *sym;
+
+ if (seg->size < rel->r_offset)
+ return grub_error (GRUB_ERR_BAD_MODULE,
+ "reloc offset is out of the segment");
+
+ addr = (Elf_Word *) ((char *) seg->addr + rel->r_offset);
+ sym = (Elf_Sym *) ((char *) mod->symtab
+ + entsize * ELF_R_SYM (rel->r_info));
+ if (sym->st_value == (grub_addr_t) &__gnu_local_gp_dummy)
+ sym->st_value = (grub_addr_t) gp;
+
+ switch (ELF_R_TYPE (rel->r_info))
+ {
+ case R_MIPS_HI16:
+ {
+ grub_uint32_t value;
+ Elf_Rel *rel2;
+
+ /* Handle partner lo16 relocation. Lower part is
+ treated as signed. Hence add 0x8000 to compensate.
+ */
+ value = (*(grub_uint16_t *) addr << 16)
+ + sym->st_value + 0x8000;
+ for (rel2 = rel + 1; rel2 < max; rel2++)
+ if (ELF_R_SYM (rel2->r_info)
+ == ELF_R_SYM (rel->r_info)
+ && ELF_R_TYPE (rel2->r_info) == R_MIPS_LO16)
+ {
+ value += *(grub_int16_t *)
+ ((char *) seg->addr + rel2->r_offset);
+ break;
+ }
+ *(grub_uint16_t *) addr = (value >> 16) & 0xffff;
+ }
+ break;
+ case R_MIPS_LO16:
+ *(grub_uint16_t *) addr += (sym->st_value) & 0xffff;
+ break;
+ case R_MIPS_32:
+ *(grub_uint32_t *) addr += sym->st_value;
+ break;
+ case R_MIPS_GPREL32:
+ *(grub_uint32_t *) addr = sym->st_value
+ + *(grub_uint32_t *) addr + gp0 - (grub_uint32_t)gp;
+ break;
+
+ case R_MIPS_26:
+ {
+ grub_uint32_t value;
+ grub_uint32_t raw;
+ raw = (*(grub_uint32_t *) addr) & 0x3ffffff;
+ value = raw << 2;
+ value += sym->st_value;
+ raw = (value >> 2) & 0x3ffffff;
+
+ *(grub_uint32_t *) addr =
+ raw | ((*(grub_uint32_t *) addr) & 0xfc000000);
+ }
+ break;
+ case R_MIPS_GOT16:
+ case R_MIPS_CALL16:
+ /* FIXME: reuse*/
+ *gpptr = sym->st_value + *(grub_uint16_t *) addr;
+ *(grub_uint16_t *) addr
+ = sizeof (grub_uint32_t) * (gpptr - gp);
+ gpptr++;
+ break;
+ case R_MIPS_JALR:
+ break;
+ default:
+ {
+ grub_free (gp);
+ return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
+ "Unknown relocation type %d\n",
+ ELF_R_TYPE (rel->r_info));
+ }
+ break;
+ }
+ }
+ }
+ }
+
+ return GRUB_ERR_NONE;
+}
+
+void
+grub_arch_dl_init_linker (void)
+{
+ grub_dl_register_symbol ("__gnu_local_gp", &__gnu_local_gp_dummy, 0);
+}
+
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