add support for embedded relocs in m68k ELF port

1 files changed, 138 insertions, 0 deletions

diff --git a/bfd/elf32-m68k.c b/bfd/elf32-m68k.c
index 96d636c5d1..d53cfdf45a 100644
--- a/bfd/elf32-m68k.c
+++ b/bfd/elf32-m68k.c
@@ -2179,6 +2179,144 @@ elf_m68k_finish_dynamic_sections (output_bfd, info)
   return true;
 }
 
+/* Given a .data section and a .emreloc in-memory section, store
+   relocation information into the .emreloc section which can be
+   used at runtime to relocate the section.  This is called by the
+   linker when the --embedded-relocs switch is used.  This is called
+   after the add_symbols entry point has been called for all the
+   objects, and before the final_link entry point is called.  */
+
+boolean
+bfd_m68k_elf32_create_embedded_relocs (abfd, info, datasec, relsec, errmsg)
+     bfd *abfd;
+     struct bfd_link_info *info;
+     asection *datasec;
+     asection *relsec;
+     char **errmsg;
+{
+  Elf_Internal_Shdr *symtab_hdr;
+  Elf32_External_Sym *extsyms;
+  Elf32_External_Sym *free_extsyms = NULL;
+  Elf_Internal_Rela *internal_relocs;
+  Elf_Internal_Rela *free_relocs = NULL;
+  Elf_Internal_Rela *irel, *irelend;
+  bfd_byte *p;
+
+  BFD_ASSERT (! info->relocateable);
+
+  *errmsg = NULL;
+
+  if (datasec->reloc_count == 0)
+    return true;
+
+  symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
+  /* Read this BFD's symbols if we haven't done so already, or get the cached
+     copy if it exists.  */
+  if (symtab_hdr->contents != NULL)
+    extsyms = (Elf32_External_Sym *) symtab_hdr->contents;
+  else
+    {
+      /* Go get them off disk.  */
+      if (info->keep_memory)
+	extsyms = ((Elf32_External_Sym *)
+		   bfd_alloc (abfd, symtab_hdr->sh_size));
+      else
+	extsyms = ((Elf32_External_Sym *)
+		   bfd_malloc (symtab_hdr->sh_size));
+      if (extsyms == NULL)
+	goto error_return;
+      if (! info->keep_memory)
+	free_extsyms = extsyms;
+      if (bfd_seek (abfd, symtab_hdr->sh_offset, SEEK_SET) != 0
+	  || (bfd_read (extsyms, 1, symtab_hdr->sh_size, abfd)
+	      != symtab_hdr->sh_size))
+	goto error_return;
+      if (info->keep_memory)
+	symtab_hdr->contents = extsyms;
+    }
+
+  /* Get a copy of the native relocations.  */
+  internal_relocs = (_bfd_elf32_link_read_relocs
+		     (abfd, datasec, (PTR) NULL, (Elf_Internal_Rela *) NULL,
+		      info->keep_memory));
+  if (internal_relocs == NULL)
+    goto error_return;
+  if (! info->keep_memory)
+    free_relocs = internal_relocs;
+
+  relsec->contents = (bfd_byte *) bfd_alloc (abfd, datasec->reloc_count * 12);
+  if (relsec->contents == NULL)
+    goto error_return;
+
+  p = relsec->contents;
+
+  irelend = internal_relocs + datasec->reloc_count;
+  for (irel = internal_relocs; irel < irelend; irel++, p += 12)
+    {
+      asection *targetsec;
+
+      /* We are going to write a four byte longword into the runtime
+       reloc section.  The longword will be the address in the data
+       section which must be relocated.  It is followed by the name
+       of the target section NUL-padded or truncated to 8
+       characters.  */
+
+      /* We can only relocate absolute longword relocs at run time.  */
+      if (ELF32_R_TYPE (irel->r_info) != (int) R_68K_32)
+	{
+	  *errmsg = _("unsupported reloc type");
+	  bfd_set_error (bfd_error_bad_value);
+	  goto error_return;
+	}
+
+      /* Get the target section referred to by the reloc.  */
+      if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
+	{
+	  Elf_Internal_Sym isym;
+
+	  /* A local symbol.  */
+	  bfd_elf32_swap_symbol_in (abfd,
+				    extsyms + ELF32_R_SYM (irel->r_info),
+				    &isym);
+
+	  targetsec = bfd_section_from_elf_index (abfd, isym.st_shndx);
+	}
+      else
+	{
+	  unsigned long indx;
+	  struct elf_link_hash_entry *h;
+
+	  /* An external symbol.  */
+	  indx = ELF32_R_SYM (irel->r_info) - symtab_hdr->sh_info;
+	  h = elf_sym_hashes (abfd)[indx];
+	  BFD_ASSERT (h != NULL);
+	  if (h->root.type == bfd_link_hash_defined
+	      || h->root.type == bfd_link_hash_defweak)
+	    targetsec = h->root.u.def.section;
+	  else
+	    targetsec = NULL;
+	}
+
+      bfd_put_32 (abfd, irel->r_offset + datasec->output_offset, p);
+      memset (p + 4, 0, 8);
+      if (targetsec != NULL)
+	strncpy (p + 4, targetsec->output_section->name, 8);
+    }
+  
+  if (free_extsyms != NULL)
+    free (free_extsyms);
+  if (free_relocs != NULL)
+    free (free_relocs);
+  return true;
+
+error_return:
+  if (free_extsyms != NULL)
+    free (free_extsyms);
+  if (free_relocs != NULL)
+    free (free_relocs);
+  return false;
+}
+
 #define TARGET_BIG_SYM			bfd_elf32_m68k_vec
 #define TARGET_BIG_NAME			"elf32-m68k"
 #define ELF_MACHINE_CODE		EM_68K