commit b4cbbe8f7294070cc93a71ace78f134965ddad82

Author: Andreas Krebbel <krebbel@linux.vnet.ibm.com>

Date:   Thu Jun 8 17:24:50 2017 +0200

    S/390: Add support for pgste marker

    This patch adds a new S/390 specific segment type: PT_S390_PGSTE.  For

    binaries marked with that segment the kernel will allocate 4k page

    tables.  The only user so far will be qemu.

    ld/ChangeLog:

    2017-06-23  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

            * Makefile.in: Add s390.em as build dependency.

            * emulparams/elf64_s390.sh (EXTRA_EM_FILE): Add s390.em.

            * emultempl/s390.em: New file.

            * gen-doc.texi: Add documentation for --s390-pgste option.

            * ld.texinfo: Likewise.

    include/ChangeLog:

    2017-06-23  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

            * elf/s390.h (PT_S390_PGSTE): Define macro.

    binutils/ChangeLog:

    2017-06-23  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

            * readelf.c (get_s390_segment_type): Add support for the new

            segment type PT_S390_PGSTE.

            (get_segment_type): Call get_s390_segment_type.

    elfcpp/ChangeLog:

    2017-06-23  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

            * elfcpp.h (enum PT): Add PT_S390_PGSTE to enum.

    bfd/ChangeLog:

    2017-06-23  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

            * elf-s390.h: New file.

            * elf64-s390.c (struct elf_s390_link_hash_table): Add params

            field.

            (elf_s390_additional_program_headers): New function.

            (elf_s390_modify_segment_map): New function.

            (bfd_elf_s390_set_options): New function.

            (elf_backend_additional_program_headers)

            (elf_backend_modify_segment_map): Add macro definitions.

--- /dev/null

+++ b/bfd/elf-s390.h

@@ -0,0 +1,29 @@

+/* S/390-specific support for ELF.

+   Copyright (C) 2017 Free Software Foundation, Inc.

+

+   This file is part of BFD, the Binary File Descriptor library.

+

+   This program 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.

+

+   This program 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 this program; if not, write to the Free Software

+   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,

+   MA 02110-1301, USA.  */

+

+/* Used to pass info between ld and bfd.  */

+struct s390_elf_params

+{

+  /* Tell the kernel to allocate 4k page tables.  */

+  int pgste;

+};

+

+bfd_boolean bfd_elf_s390_set_options (struct bfd_link_info *info,

+				      struct s390_elf_params *params);

--- a/bfd/elf64-s390.c

+++ b/bfd/elf64-s390.c

@@ -25,6 +25,7 @@

 #include "libbfd.h"

 #include "elf-bfd.h"

 #include "elf/s390.h"

+#include "elf-s390.h"

 #include <stdarg.h>

 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value

@@ -660,6 +661,9 @@ struct elf_s390_link_hash_table

   /* Small local sym cache.  */

   struct sym_cache sym_cache;

+

+  /* Options passed from the linker.  */

+  struct s390_elf_params *params;

 };

 /* Get the s390 ELF linker hash table from a link_info structure.  */

@@ -3966,6 +3970,70 @@ elf64_s390_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)

   return elf_s390_merge_obj_attributes (ibfd, info);

 }

+/* We may add a PT_S390_PGSTE program header.  */

+

+static int

+elf_s390_additional_program_headers (bfd *abfd ATTRIBUTE_UNUSED,

+				     struct bfd_link_info *info)

+{

+  struct elf_s390_link_hash_table *htab;

+

+  htab = elf_s390_hash_table (info);

+  return htab->params->pgste;

+}

+

+

+/* Add the PT_S390_PGSTE program header.  */

+

+static bfd_boolean

+elf_s390_modify_segment_map (bfd *abfd ATTRIBUTE_UNUSED,

+			     struct bfd_link_info *info)

+{

+  struct elf_s390_link_hash_table *htab;

+  struct elf_segment_map *m, *pm = NULL;

+

+  htab = elf_s390_hash_table (info);

+  if (!htab->params->pgste)

+    return TRUE;

+

+  /* If there is already a PT_S390_PGSTE header, avoid adding

+     another.  */

+  m = elf_seg_map (abfd);

+  while (m && m->p_type != PT_S390_PGSTE)

+    {

+      pm = m;

+      m = m->next;

+    }

+

+  if (m)

+    return TRUE;

+

+  m = (struct elf_segment_map *)

+    bfd_zalloc (abfd, sizeof (struct elf_segment_map));

+  if (m == NULL)

+    return FALSE;

+  m->p_type = PT_S390_PGSTE;

+  m->count = 0;

+  m->next = NULL;

+  if (pm)

+    pm->next = m;

+

+  return TRUE;

+}

+

+bfd_boolean

+bfd_elf_s390_set_options (struct bfd_link_info *info,

+			  struct s390_elf_params *params)

+{

+  struct elf_s390_link_hash_table *htab;

+

+  htab = elf_s390_hash_table (info);

+  htab->params = params;

+

+  return TRUE;

+}

+

+

 /* Why was the hash table entry size definition changed from

    ARCH_SIZE/8 to 4? This breaks the 64 bit dynamic linker and

    this is the only reason for the s390_elf64_size_info structure.  */

@@ -4046,6 +4114,8 @@ const struct elf_size_info s390_elf64_size_info =

 #define elf_backend_plt_sym_val		      elf_s390_plt_sym_val

 #define elf_backend_add_symbol_hook           elf_s390_add_symbol_hook

 #define elf_backend_sort_relocs_p             elf_s390_elf_sort_relocs_p

+#define elf_backend_additional_program_headers elf_s390_additional_program_headers

+#define elf_backend_modify_segment_map	      elf_s390_modify_segment_map

 #define bfd_elf64_mkobject		elf_s390_mkobject

 #define elf_backend_object_p		elf_s390_object_p

--- a/include/elf/s390.h

+++ b/include/elf/s390.h

@@ -37,6 +37,9 @@

 #define EF_S390_HIGH_GPRS        0x00000001

+/* Request 4k page table size.  */

+#define PT_S390_PGSTE (PT_LOPROC + 0)

+

 /* Relocation types.  */

 START_RELOC_NUMBERS (elf_s390_reloc_type)