From 73911575dd67eaa09837fe0f691655553c3dea69 Mon Sep 17 00:00:00 2001
From: phcoder <phcoder@debian>
Date: Sun, 2 Jan 2011 14:58:57 +0100
Subject: [PATCH] support for registering functions from modules (not tested
 yet)

---
 grub-core/kern/dl.c       | 20 +++++++++++++++++---
 grub-core/kern/emu/full.c |  8 ++++++++
 grub-core/kern/ia64/dl.c  | 30 ++++++++++++++++++++----------
 include/grub/dl.h         |  9 +++++++++
 4 files changed, 54 insertions(+), 13 deletions(-)

diff --git a/grub-core/kern/dl.c b/grub-core/kern/dl.c
index 2f2493fca..9dfff5287 100644
--- a/grub-core/kern/dl.c
+++ b/grub-core/kern/dl.c
@@ -360,9 +360,22 @@ grub_dl_resolve_symbols (grub_dl_t mod, Elf_Ehdr *e)
 	  sym->st_value += (Elf_Addr) grub_dl_get_section_addr (mod,
 								sym->st_shndx);
 	  if (bind != STB_LOCAL)
-	    if (grub_dl_register_symbol (name, (void *) sym->st_value, mod))
-	      return grub_errno;
-
+	    {
+#ifdef __ia64__
+	      /* FIXME: free descriptor once it's not used anymore. */
+	      char **desc;
+	      desc = grub_malloc (2 * sizeof (char *));
+	      if (!desc)
+		return grub_errno;
+	      desc[0] = (void *) sym->st_value;
+	      desc[1] = mod->gp;
+	      if (grub_dl_register_symbol (name, (void *) desc, mod))
+		return grub_errno;
+#else
+	      if (grub_dl_register_symbol (name, (void *) sym->st_value, mod))
+		return grub_errno;
+#endif
+	    }
 	  if (grub_strcmp (name, "grub_mod_init") == 0)
 	    mod->init = sym->st_value;
 	  else if (grub_strcmp (name, "grub_mod_fini") == 0)
@@ -552,6 +565,7 @@ grub_dl_load_core (void *addr, grub_size_t size)
   if (grub_dl_resolve_name (mod, e)
       || grub_dl_resolve_dependencies (mod, e)
       || grub_dl_load_segments (mod, e)
+      || grub_arch_dl_allocate_gp (mod, e)
       || grub_dl_resolve_symbols (mod, e)
       || grub_arch_dl_relocate_symbols (mod, e))
     {
diff --git a/grub-core/kern/emu/full.c b/grub-core/kern/emu/full.c
index 0396d0ab4..67a125301 100644
--- a/grub-core/kern/emu/full.c
+++ b/grub-core/kern/emu/full.c
@@ -56,4 +56,12 @@ grub_arch_dl_get_tramp_size (const void *ehdr __attribute__ ((unused)),
 {
   return ~(grub_size_t)0;
 }
+
+grub_err_t
+grub_arch_dl_allocate_gp (grub_dl_t mod __attribute__ ((unused)),
+			  const void *ehdr __attribute__ ((unused)))
+{
+  return GRUB_ERR_BAD_MODULE;
+}
+
 #endif
diff --git a/grub-core/kern/ia64/dl.c b/grub-core/kern/ia64/dl.c
index 24fa01b90..1fbe185b4 100644
--- a/grub-core/kern/ia64/dl.c
+++ b/grub-core/kern/ia64/dl.c
@@ -154,16 +154,13 @@ grub_arch_dl_get_tramp_size (const void *ehdr, unsigned sec)
   return cnt * sizeof (struct ia64_trampoline);
 }
 
-/* Relocate symbols.  */
 grub_err_t
-grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr)
+grub_arch_dl_allocate_gp (grub_dl_t mod, const void *ehdr)
 {
-  Elf_Ehdr *e = ehdr;
-  Elf_Shdr *s;
-  Elf_Word entsize;
-  unsigned i;
-  grub_uint64_t *gp, *gpptr;
   grub_size_t gp_size = 0;
+  const Elf_Ehdr *e = ehdr;
+  const Elf_Shdr *s;
+  unsigned i;
 
   for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
        i < e->e_shnum;
@@ -199,10 +196,23 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr)
   if (gp_size > MASK19)
     return grub_error (GRUB_ERR_OUT_OF_RANGE, "gp too big");
 
-  gpptr = gp = grub_malloc (gp_size);
-  if (!gp)
+  mod->gp = grub_malloc (gp_size);
+  if (!mod->gp)
     return grub_errno;
-  mod->gp = (char *) gp;
+  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_uint64_t *gp, *gpptr;
+
+  gp = gpptr = (grub_uint64_t *) mod->gp;
 
   /* Find a symbol table.  */
   for (i = 0, s = (Elf_Shdr *) ((char *) e + e->e_shoff);
diff --git a/include/grub/dl.h b/include/grub/dl.h
index e04285280..c43c30ca7 100644
--- a/include/grub/dl.h
+++ b/include/grub/dl.h
@@ -124,6 +124,8 @@ void grub_arch_dl_init_linker (void);
 
 #ifdef __ia64__
 grub_size_t grub_arch_dl_get_tramp_size (const void *ehdr, unsigned sec);
+grub_err_t grub_arch_dl_allocate_gp (grub_dl_t mod, const void *ehdr);
+
 #define GRUB_ARCH_DL_TRAMP_ALIGN 16
 #else
 static inline grub_size_t
@@ -131,6 +133,13 @@ grub_arch_dl_get_tramp_size (const void *ehdr __attribute__ ((unused)), int sec
 {
   return 0;
 }
+static inline grub_err_t
+grub_arch_dl_allocate_gp (grub_dl_t mod __attribute__ ((unused)),
+			  const void *ehdr __attribute__ ((unused)))
+{
+  return GRUB_ERR_NONE;
+}
+
 #define GRUB_ARCH_DL_TRAMP_ALIGN 1
 #endif