[glibc] powerpc: Remove _dl_var_init

[glibc] powerpc: Remove _dl_var_init

[Florian Weimer]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b7fc189f7f0b42145e5ebc23f2bcae118607d7bb

commit b7fc189f7f0b42145e5ebc23f2bcae118607d7bb
Author: Florian Weimer <fweimer@redhat.com>
Date:   Mon May 17 09:59:14 2021 +0200

    powerpc: Remove _dl_var_init
    
    The generic __rtld_static_init code handles GLRO (dl_pagesize),
    GLRO (dl_auxv), GLRO (dl_hwcap), GLRO (dl_hwcap2).
    GLRO (dl_cache_line_size) is handled in an __rtld_static_init_arch
    override.
    
    Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

Diff:
---
 sysdeps/unix/sysv/linux/powerpc/Makefile           |  4 -
 sysdeps/unix/sysv/linux/powerpc/Versions           |  6 --
 sysdeps/unix/sysv/linux/powerpc/dl-static.c        | 96 ----------------------
 .../powerpc/{ldsodefs.h => rtld_static_init.h}     | 26 +++---
 4 files changed, 10 insertions(+), 122 deletions(-)

diff --git a/sysdeps/unix/sysv/linux/powerpc/Makefile b/sysdeps/unix/sysv/linux/powerpc/Makefile
index a093cda68b..06f1328fab 100644
--- a/sysdeps/unix/sysv/linux/powerpc/Makefile
+++ b/sysdeps/unix/sysv/linux/powerpc/Makefile
@@ -13,10 +13,6 @@ gen-as-const-headers += ucontext_i.sym
 endif
 
 ifeq ($(subdir),elf)
-ifeq ($(build-shared),yes)
-# This is needed for DSO loading from static binaries.
-sysdep-dl-routines += dl-static
-endif
 # Otherwise tst-tls-dlinfo fails due to tst-tlsmod2.so using static tls.
 LDFLAGS-tst-tlsmod2.so += -Wl,--no-tls-get-addr-optimize
 endif
diff --git a/sysdeps/unix/sysv/linux/powerpc/Versions b/sysdeps/unix/sysv/linux/powerpc/Versions
index cc28d84744..416272b718 100644
--- a/sysdeps/unix/sysv/linux/powerpc/Versions
+++ b/sysdeps/unix/sysv/linux/powerpc/Versions
@@ -1,9 +1,3 @@
-ld {
-  GLIBC_PRIVATE {
-  # used for loading by static libraries
-    _dl_var_init;
-  }
-}
 libc {
   GLIBC_PRIVATE {
     __vdso_get_tbfreq;
diff --git a/sysdeps/unix/sysv/linux/powerpc/dl-static.c b/sysdeps/unix/sysv/linux/powerpc/dl-static.c
deleted file mode 100644
index e35ca4c44b..0000000000
--- a/sysdeps/unix/sysv/linux/powerpc/dl-static.c
+++ /dev/null
@@ -1,96 +0,0 @@
-/* Variable initialization.  PowerPC version.
-   Copyright (C) 2013-2021 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, see
-   <https://www.gnu.org/licenses/>.  */
-
-#include <ldsodefs.h>
-
-#ifdef SHARED
-
-void
-_dl_var_init (void *array[])
-{
-  /* It has to match "variables" below. */
-  enum
-    {
-      DL_PAGESIZE = 0,
-      DL_AUXV = 1,
-      DL_HWCAP = 2,
-      DL_HWCAP2 = 3,
-      DL_CACHE_LINE_SIZE = 4
-    };
-
-  GLRO(dl_pagesize) = *((size_t *) array[DL_PAGESIZE]);
-  GLRO(dl_auxv) = (ElfW(auxv_t) *) *((size_t *) array[DL_AUXV]);
-  GLRO(dl_hwcap)  = *((unsigned long int *) array[DL_HWCAP]);
-  GLRO(dl_hwcap2) = *((unsigned long int *) array[DL_HWCAP2]);
-  GLRO(dl_cache_line_size) = (int) *((int *) array[DL_CACHE_LINE_SIZE]);
-}
-
-#else
-
-static void *variables[] =
-{
-  &GLRO(dl_pagesize),
-  &GLRO(dl_auxv),
-  &GLRO(dl_hwcap),
-  &GLRO(dl_hwcap2),
-  &GLRO(dl_cache_line_size)
-};
-
-static void
-_dl_unprotect_relro (struct link_map *l)
-{
-  ElfW(Addr) start = ((l->l_addr + l->l_relro_addr)
-		      & ~(GLRO(dl_pagesize) - 1));
-  ElfW(Addr) end = ((l->l_addr + l->l_relro_addr + l->l_relro_size)
-		    & ~(GLRO(dl_pagesize) - 1));
-
-  if (start != end)
-    __mprotect ((void *) start, end - start, PROT_READ | PROT_WRITE);
-}
-
-void
-_dl_static_init (struct link_map *l)
-{
-  struct link_map *rtld_map = l;
-  struct r_scope_elem **scope;
-  const ElfW(Sym) *ref = NULL;
-  lookup_t loadbase;
-  void (*f) (void *[]);
-  size_t i;
-
-  loadbase = _dl_lookup_symbol_x ("_dl_var_init", l, &ref, l->l_local_scope,
-				  NULL, 0, 1, NULL);
-
-  for (scope = l->l_local_scope; *scope != NULL; scope++)
-    for (i = 0; i < (*scope)->r_nlist; i++)
-      if ((*scope)->r_list[i] == loadbase)
-	{
-	  rtld_map = (*scope)->r_list[i];
-	  break;
-	}
-
-  if (ref != NULL)
-    {
-      f = (void (*) (void *[])) DL_SYMBOL_ADDRESS (loadbase, ref);
-      _dl_unprotect_relro (rtld_map);
-      f (variables);
-      _dl_protect_relro (rtld_map);
-    }
-}
-
-#endif
diff --git a/sysdeps/unix/sysv/linux/powerpc/ldsodefs.h b/sysdeps/unix/sysv/linux/powerpc/rtld_static_init.h
similarity index 59%
rename from sysdeps/unix/sysv/linux/powerpc/ldsodefs.h
rename to sysdeps/unix/sysv/linux/powerpc/rtld_static_init.h
index bb9c262299..730ac19f77 100644
--- a/sysdeps/unix/sysv/linux/powerpc/ldsodefs.h
+++ b/sysdeps/unix/sysv/linux/powerpc/rtld_static_init.h
@@ -1,6 +1,5 @@
-/* Run-time dynamic linker data structures for loaded ELF shared objects.
-   PowerPC version.
-   Copyright (C) 2013-2021 Free Software Foundation, Inc.
+/* Partial initialization of ld.so loaded via static dlopen.  powerpc helper.
+   Copyright (C) 2021 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
@@ -17,17 +16,12 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-#ifndef _LDSODEFS_H
+static inline void
+__rtld_static_init_arch (struct link_map *map, struct rtld_global_ro *dl)
+{
+  /* This field does not exist in the generic _rtld_global_ro version.  */
 
-/* Get the real definitions.  */
-#include_next <ldsodefs.h>
-
-/* Now define our stuff.  */
-
-/* We need special support to initialize DSO loaded for statically linked
-   binaries.  */
-extern void _dl_static_init (struct link_map *map);
-#undef DL_STATIC_INIT
-#define DL_STATIC_INIT(map) _dl_static_init (map)
-
-#endif /* ldsodefs.h */
+  extern __typeof (dl->_dl_cache_line_size) _dl_cache_line_size
+    attribute_hidden;
+  dl->_dl_cache_line_size = _dl_cache_line_size;
+}