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.

1 files changed, 64 insertions, 0 deletions

diff --git a/ld/emultempl/s390.em b/ld/emultempl/s390.em
new file mode 100644
index 0000000..536104e
--- /dev/null
+++ b/ld/emultempl/s390.em
@@ -0,0 +1,64 @@
+# This shell script emits a C file. -*- C -*-
+# Copyright (C) 2017 Free Software Foundation, Inc.
+#
+# This file is part of the GNU Binutils.
+#
+# 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; see the file COPYING3. If not,
+# see <http://www.gnu.org/licenses/>.
+#
+
+# This file is sourced from elf-generic.em, and defines S/390
+# specific routines.
+#
+fragment <<EOF
+
+#include "ldctor.h"
+#include "elf-s390.h"
+
+static struct s390_elf_params params = { 0 };
+
+/* This is a convenient point to tell BFD about target specific flags.
+   After the output has been created, but before inputs are read.  */
+static void
+s390_elf_create_output_section_statements (void)
+{
+  if (!bfd_elf_s390_set_options (&link_info, &params))
+    einfo ("%F%P: can not init BFD: %E\n");
+}
+
+EOF
+
+# Define some shell vars to insert bits of code into the standard elf
+# parse_args and list_options functions.
+#
+PARSE_AND_LIST_PROLOGUE='
+#define OPTION_PGSTE	301
+'
+
+PARSE_AND_LIST_LONGOPTS='
+  { "s390-pgste", no_argument, NULL, OPTION_PGSTE},
+'
+
+PARSE_AND_LIST_OPTIONS='
+  fprintf (file, _("  --s390-pgste                Tell the kernel to "
+		   "allocate 4k page tables\n"));
+'
+
+PARSE_AND_LIST_ARGS_CASES='
+    case OPTION_PGSTE:
+      params.pgste = 1;
+      break;
+'
+
+LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS=s390_elf_create_output_section_statements