Introduce TLS descriptors for i386 and x86_64.

	* include/inline-hashtab.h: New file, copied from 2005's
	libiberty, with fix for memory leak imported afterwards by
	Glauber de Oliveira Costa.
	* elf/tlsdeschtab.h: New file.
	* elf/dl-reloc.c (_dl_try_allocate_static_tls): Extract from...
	(_dl_allocate_static_tls): ... here.  Rearrange failure path.
	(CHECK_STATIC_TLS): Move to...
	* elf/dynamic-link.h: ... this file.
	(TRY_STATIC_TLS): New macro.
	* elf/dl-conflict.c (CHECK_STATIC_TLS, TRY_STATIC_TLS): Override.
	* elf/elf.h (R_386_TLS_GOTDESC, R_386_TLS_DESC_CALL,
	R_386_TLS_DESC): Define.
	(R_X86_64_PC64, R_X86_GOTOFF64, R_X86_64_GOTPC32): Merge from
	binutils.
	(R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL,
	R_X86_64_TLSDESC): Define.
	(R_386_NUM, R_X86_64_NUM): Adjust.
	* sysdeps/i386/Makefile (sysdep-dl-routines, sysdep_routines,
	systep-rtld-routines): Add tlsdesc and dl-tlsdesc for elf subdir.
	(gen-as-const-headers): Add tlsdesc.sym to csu subdir.
	* sysdeps/i386/dl-lookupcfg.h: New file.  Introduce _dl_unmap to
	release tlsdesc_table.
	* sysdeps/i386/dl-machine.h: Include dl-tlsdesc.h.
	(elf_machine_type_class): Mark R_386_TLS_DESC as PLT class.
	(elf_machine_rel): Handle R_386_TLS_DESC.
	(elf_machine_rela): Likewise.
	(elf_machine_lazy_rel): Likewise.
	(elf_machine_lazy_rela): Likewise.
	* sysdeps/i386/dl-tls.h (struct dl_tls_index): Name it.
	* sysdeps/i386/dl-tlsdesc.S: New file.
	* sysdeps/i386/dl-tlsdesc.h: New file.
	* sysdeps/i386/tlsdesc.c: New file.
	* sysdeps/i386/tlsdesc.sym: New file.
	* sysdeps/i386/bits/linkmap.h (struct link_map_machine): Add
	tlsdesc_table.
	* sysdeps/x86_64/Makefile (sysdep-dl-routines, sysdep_routines,
	systep-rtld-routines): Add tlsdesc and dl-tlsdesc for elf subdir.
	(gen-as-const-headers): Add tlsdesc.sym to csu subdir.
	* sysdeps/x86_64/dl-lookupcfg.h: New file.  Introduce _dl_unmap to
	release tlsdesc_table.
	* sysdeps/x86_64/dl-machine.h: Include dl-tlsdesc.h.
	(elf_machine_runtime_setup): Set up lazy TLSDESC GOT entry.
	(elf_machine_type_class): Mark R_X86_64_TLSDESC as PLT class.
	(elf_machine_rel): Handle R_X86_64_TLSDESC.
	(elf_machine_rela): Likewise.
	(elf_machine_lazy_rel): Likewise.
	* sysdeps/x86_64/dl-tls.h (struct dl_tls_index): Name it.
	(__tls_get_addr): Do not declare for non-shared compiles.
	* sysdeps/x86_64/dl-tlsdesc.S: New file.
	* sysdeps/x86_64/dl-tlsdesc.h: New file.
	* sysdeps/x86_64/tlsdesc.c: New file.
	* sysdeps/x86_64/tlsdesc.sym: New file.
	* sysdeps/x86_64/bits/linkmap.h (struct link_map_machine): Add
	tlsdesc_table for both 32- and 64-bit structs.

1 files changed, 151 insertions, 0 deletions

diff --git a/sysdeps/x86_64/tlsdesc.c b/sysdeps/x86_64/tlsdesc.c
new file mode 100644
index 0000000..0cc32aa
--- /dev/null
+++ b/sysdeps/x86_64/tlsdesc.c
@@ -0,0 +1,151 @@
+/* Manage TLS descriptors.  x86_64 version.
+   Copyright (C) 2005, 2008 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <link.h>
+#include <ldsodefs.h>
+#include <elf/dynamic-link.h>
+#include <tls.h>
+#include <dl-tlsdesc.h>
+#include <tlsdeschtab.h>
+
+/* The following 2 functions take a caller argument, that contains the
+   address expected to be in the TLS descriptor.  If it's changed, we
+   want to return immediately.  */
+
+/* This function is used to lazily resolve TLS_DESC RELA relocations.
+   The argument location is used to hold a pointer to the relocation.  */
+
+void
+attribute_hidden
+_dl_tlsdesc_resolve_rela_fixup (struct tlsdesc volatile *td,
+				struct link_map *l)
+{
+  const ElfW(Rela) *reloc = td->arg;
+
+  if (_dl_tlsdesc_resolve_early_return_p
+      (td, (void*)(D_PTR (l, l_info[ADDRIDX (DT_TLSDESC_PLT)]) + l->l_addr)))
+    return;
+
+  /* The code below was borrowed from _dl_fixup().  */
+  const ElfW(Sym) *const symtab
+    = (const void *) D_PTR (l, l_info[DT_SYMTAB]);
+  const char *strtab = (const void *) D_PTR (l, l_info[DT_STRTAB]);
+  const ElfW(Sym) *sym = &symtab[ELFW(R_SYM) (reloc->r_info)];
+  lookup_t result;
+
+   /* Look up the target symbol.  If the normal lookup rules are not
+      used don't look in the global scope.  */
+  if (ELFW(ST_BIND) (sym->st_info) != STB_LOCAL
+      && __builtin_expect (ELFW(ST_VISIBILITY) (sym->st_other), 0) == 0)
+    {
+      const struct r_found_version *version = NULL;
+
+      if (l->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
+	{
+	  const ElfW(Half) *vernum =
+	    (const void *) D_PTR (l, l_info[VERSYMIDX (DT_VERSYM)]);
+	  ElfW(Half) ndx = vernum[ELFW(R_SYM) (reloc->r_info)] & 0x7fff;
+	  version = &l->l_versions[ndx];
+	  if (version->hash == 0)
+	    version = NULL;
+	}
+
+      result = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym,
+				    l->l_scope, version, ELF_RTYPE_CLASS_PLT,
+				    DL_LOOKUP_ADD_DEPENDENCY, NULL);
+    }
+  else
+    {
+      /* We already found the symbol.  The module (and therefore its load
+	 address) is also known.  */
+      result = l;
+    }
+
+  if (! sym)
+    {
+      td->arg = (void*)reloc->r_addend;
+      td->entry = _dl_tlsdesc_undefweak;
+    }
+  else
+    {
+#  ifndef SHARED
+      CHECK_STATIC_TLS (l, result);
+#  else
+      if (!TRY_STATIC_TLS (l, result))
+	{
+	  td->arg = _dl_make_tlsdesc_dynamic (result, sym->st_value
+					      + reloc->r_addend);
+	  td->entry = _dl_tlsdesc_dynamic;
+	}
+      else
+#  endif
+	{
+	  td->arg = (void*)(sym->st_value - result->l_tls_offset
+			    + reloc->r_addend);
+	  td->entry = _dl_tlsdesc_return;
+	}
+    }
+
+  _dl_tlsdesc_wake_up_held_fixups ();
+}
+
+/* This function is used to avoid busy waiting for other threads to
+   complete the lazy relocation.  Once another thread wins the race to
+   relocate a TLS descriptor, it sets the descriptor up such that this
+   function is called to wait until the resolver releases the
+   lock.  */
+
+void
+attribute_hidden
+_dl_tlsdesc_resolve_hold_fixup (struct tlsdesc volatile *td,
+				void *caller)
+{
+  /* Maybe we're lucky and can return early.  */
+  if (caller != td->entry)
+    return;
+
+  /* Locking here will stop execution until the running resolver runs
+     _dl_tlsdesc_wake_up_held_fixups(), releasing the lock.
+
+     FIXME: We'd be better off waiting on a condition variable, such
+     that we didn't have to hold the lock throughout the relocation
+     processing.  */
+  __rtld_lock_lock_recursive (GL(dl_load_lock));
+  __rtld_lock_unlock_recursive (GL(dl_load_lock));
+}
+
+/* Unmap the dynamic object, but also release its TLS descriptor table
+   if there is one.  */
+
+void
+internal_function
+_dl_unmap (struct link_map *map)
+{
+  __munmap ((void *) (map)->l_map_start,
+	    (map)->l_map_end - (map)->l_map_start);
+
+#if SHARED
+  /* _dl_unmap is only called for dlopen()ed libraries, for which
+     calling free() is safe, or before we've completed the initial
+     relocation, in which case calling free() is probably pointless,
+     but still safe.  */
+  if (map->l_mach.tlsdesc_table)
+    htab_delete (map->l_mach.tlsdesc_table);
+#endif
+}