nios2: sync support with glibc

Only static linking is supported for now.
More debugging and analyzing for ld.so, TLS and NPTL
is required. But at least you can bootup a static
root fileystem in Qemu.

7 files changed, 509 insertions, 0 deletions

diff --git a/ldso/ldso/nios2/dl-debug.h b/ldso/ldso/nios2/dl-debug.h
new file mode 100644
index 000000000..1fb596ae3
--- /dev/null
+++ b/ldso/ldso/nios2/dl-debug.h
@@ -0,0 +1,18 @@
+/* nios2 shared library loader suppport */
+
+static const char * const _dl_reltypes_tab[] =
+	{
+		"R_NIOS2_NONE",
+		"R_NIOS2_BFD_RELOC_32",
+		"R_NIOS2_BFD_RELOC_16",
+		"R_NIOS2_BFD_RELOC_8",
+		"R_NIOS2_GNU_VTINHERIT",
+		"R_NIOS2_GNU_VTENTRY",
+		"R_NIOS2_GOT16",
+		"R_NIOS2_CALL16",
+		"R_NIOS2_JUMP_SLOT",
+		"R_NIOS2_GLOB_DAT",
+		"R_NIOS2_RELATIVE",
+		"R_NIOS2_GOTOFF",
+		"R_NIOS2_COPY",
+	};
diff --git a/ldso/ldso/nios2/dl-inlines.h b/ldso/ldso/nios2/dl-inlines.h
new file mode 100644
index 000000000..7cf7e4afd
--- /dev/null
+++ b/ldso/ldso/nios2/dl-inlines.h
@@ -0,0 +1,12 @@
+
+unsigned int
+internal_function
+_dl_nios2_get_gp_value (struct link_map *main_map)
+{ 
+  ElfW(Dyn) *dyn = main_map->l_ld;
+  for (dyn = main_map->l_ld; dyn->d_tag != DT_NULL; ++dyn)
+    if (dyn->d_tag == DT_NIOS2_GP)
+      return (unsigned int)(dyn->d_un.d_ptr);
+  return 0;
+}
+
diff --git a/ldso/ldso/nios2/dl-startup.h b/ldso/ldso/nios2/dl-startup.h
new file mode 100644
index 000000000..982e55532
--- /dev/null
+++ b/ldso/ldso/nios2/dl-startup.h
@@ -0,0 +1,34 @@
+__asm__ ("\
+	.text\n\
+	.globl _start\n\
+	.type _start, %function\n\
+_start:\n\
+        mov r4, sp\n\
+        br _dl_start\n\
+	mov r16, r4\n\
+        jmp r16\n\
+");
+
+/*
+ * Get a pointer to the argv array.  On many platforms this can be just
+ * the address of the first argument, on other platforms we need to
+ * do something a little more subtle here.
+ */
+#define GET_ARGV(ARGVP, ARGS) ARGVP = (((unsigned long*) ARGS)+1)
+
+/* The ld.so library requires relocations */
+#define ARCH_NEEDS_BOOTSTRAP_RELOCS
+
+static __always_inline
+void PERFORM_BOOTSTRAP_RELOC(ELF_RELOC *rpnt, unsigned long *reloc_addr,
+	unsigned long symbol_addr, unsigned long load_addr, attribute_unused Elf32_Sym *symtab)
+{
+	switch (ELF_R_TYPE(rpnt->r_info)) {
+		case R_NIOS2_RELATIVE:
+			*reloc_addr = load_addr + rpnt->r_addend;
+			break;
+		default:
+			_dl_exit(1);
+			break;
+	}
+}
diff --git a/ldso/ldso/nios2/dl-syscalls.h b/ldso/ldso/nios2/dl-syscalls.h
new file mode 100644
index 000000000..f40c4fd31
--- /dev/null
+++ b/ldso/ldso/nios2/dl-syscalls.h
@@ -0,0 +1 @@
+/* stub for arch-specific syscall issues */
diff --git a/ldso/ldso/nios2/dl-sysdep.h b/ldso/ldso/nios2/dl-sysdep.h
new file mode 100644
index 000000000..5ae3ce311
--- /dev/null
+++ b/ldso/ldso/nios2/dl-sysdep.h
@@ -0,0 +1,74 @@
+/* Use reloca */
+#define ELF_USES_RELOCA
+
+#include <elf.h>
+
+/* Initialise the GOT */
+#define INIT_GOT(GOT_BASE,MODULE)					\
+do {									\
+	GOT_BASE[2] = (unsigned long) _dl_linux_resolve;		\
+	GOT_BASE[1] = (unsigned long) MODULE;				\
+} while(0)
+
+/* Here we define the magic numbers that this dynamic loader should accept */
+
+#define MAGIC1 EM_ALTERA_NIOS2
+#undef  MAGIC2
+/* Used for error messages */
+#define ELF_TARGET "nios2"
+
+struct elf_resolve;
+unsigned long _dl_linux_resolver(struct elf_resolve * tpnt, int reloc_entry);
+
+/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry, so
+   PLT entries should not be allowed to define the value.
+   ELF_RTYPE_CLASS_COPY iff TYPE should not be allowed to resolve to one
+   of the main executable's symbols, as for a COPY reloc.  */
+#define elf_machine_type_class(type)				\
+  ((((type) == R_NIOS2_JUMP_SLOT				\
+     || (type) == R_NIOS2_TLS_DTPMOD				\
+     || (type) == R_NIOS2_TLS_DTPREL				\
+     || (type) == R_NIOS2_TLS_TPREL) * ELF_RTYPE_CLASS_PLT)	\
+   | (((type) == R_NIOS2_COPY) * ELF_RTYPE_CLASS_COPY))
+
+/* Return the link-time address of _DYNAMIC.  Conveniently, this is the
+   first element of the GOT.  */
+static inline Elf32_Addr
+elf_machine_dynamic (void)
+{
+  Elf32_Addr *dynamic;
+  int tmp;
+  __asm__ ("nextpc\t%0\n\t"
+       "1: movhi\t%1, %%hiadj(_GLOBAL_OFFSET_TABLE_ - 1b)\n\t"
+       "addi\t%1, %1, %%lo(_GLOBAL_OFFSET_TABLE_ - 1b)\n\t"
+       "add\t%0, %0, %1\n"
+       : "=r" (dynamic), "=r" (tmp));
+  return *dynamic;
+}
+
+/* Return the run-time load address of the shared object.  */
+static inline Elf32_Addr
+elf_machine_load_address (void)
+{
+  Elf32_Addr result;
+  int tmp;
+  __asm__ ("nextpc\t%0\n\t"
+       "1: movhi\t%1, %%hiadj(1b)\n\t"
+       "addi\t%1, %1, %%lo(1b)\n\t"
+       "sub\t%0, %0, %1\n"
+       : "=r" (result), "=r" (tmp));
+  return result;
+}
+
+static __always_inline void
+elf_machine_relative (Elf32_Addr load_off, const Elf32_Addr rel_addr,
+		      Elf32_Word relative_count)
+{
+	Elf32_Rel * rpnt = (void *) rel_addr;
+	do {
+		Elf32_Addr *const reloc_addr = (void *) (load_off + (rpnt)->r_offset);
+
+		*reloc_addr += load_off;
+	} while (--relative_count);
+}
+
diff --git a/ldso/ldso/nios2/elfinterp.c b/ldso/ldso/nios2/elfinterp.c
new file mode 100644
index 000000000..bdbaa3383
--- /dev/null
+++ b/ldso/ldso/nios2/elfinterp.c
@@ -0,0 +1,297 @@
+/* nios2 ELF shared library loader suppport
+ *
+ * Copyright (c) 1994-2000 Eric Youngdale, Peter MacDonald,
+ *                              David Engel, Hongjiu Lu and Mitch D'Souza
+ * Copyright (C) 2001-2004 Erik Andersen
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. The name of the above contributors may not be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "ldso.h"
+
+/* Program to load an ELF binary on a linux system, and run it.
+   References to symbols in sharable libraries can be resolved by either
+   an ELF sharable library or a linux style of shared library. */
+
+extern int _dl_linux_resolve(void);
+
+unsigned long
+_dl_linux_resolver(struct elf_resolve *tpnt, int reloc_entry)
+{
+	ELF_RELOC *this_reloc;
+	char *strtab;
+	ElfW(Sym) *symtab;
+	int symtab_index;
+	char *rel_addr;
+	char *new_addr;
+	char **got_addr;
+	ElfW(Addr) instr_addr;
+	char *symname;
+
+	rel_addr = (char *)tpnt->dynamic_info[DT_JMPREL];
+	this_reloc = (ELF_RELOC *)(rel_addr + reloc_entry);
+	symtab_index = ELF_R_SYM(this_reloc->r_info);
+
+	symtab = (ElfW(Sym) *)tpnt->dynamic_info[DT_SYMTAB];
+	strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
+	symname = strtab + symtab[symtab_index].st_name;
+
+	/* Address of the jump instruction to fix up. */
+	instr_addr = (this_reloc->r_offset + tpnt->loadaddr);
+	got_addr = (char **)instr_addr;
+
+	/* Get the address of the GOT entry. */
+	new_addr = _dl_find_hash(symname, &_dl_loaded_modules->symbol_scope, tpnt, ELF_RTYPE_CLASS_PLT, NULL);
+	if (unlikely(!new_addr)) {
+		_dl_dprintf(2, "%s: Can't resolve symbol '%s'\n", _dl_progname, symname);
+		_dl_exit(1);
+	}
+
+#if defined (__SUPPORT_LD_DEBUG__)
+	if (_dl_debug_bindings) {
+		_dl_dprintf(_dl_debug_file, "\nresolve function: %s", symname);
+		if (_dl_debug_detail)
+			_dl_dprintf(_dl_debug_file,
+			            "\tpatched: %x ==> %x @ %x\n",
+			            *got_addr, new_addr, got_addr);
+	}
+	if (!_dl_debug_nofixups)
+#endif
+		*got_addr = new_addr;
+
+	return (unsigned long)new_addr;
+}
+
+static int
+_dl_parse(struct elf_resolve *tpnt, struct r_scope_elem *scope,
+	  unsigned long rel_addr, unsigned long rel_size,
+	  int (*reloc_fnc)(struct elf_resolve *tpnt, struct r_scope_elem *scope,
+			   ELF_RELOC *rpnt, ElfW(Sym) *symtab, char *strtab))
+{
+	unsigned int i;
+	char *strtab;
+	ElfW(Sym) *symtab;
+	ELF_RELOC *rpnt;
+	int symtab_index;
+
+	/* Parse the relocation information. */
+	rpnt = (ELF_RELOC *)rel_addr;
+	rel_size /= sizeof(ELF_RELOC);
+
+	symtab = (ElfW(Sym) *)tpnt->dynamic_info[DT_SYMTAB];
+	strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
+
+	for (i = 0; i < rel_size; i++, rpnt++) {
+		int res;
+
+		symtab_index = ELF_R_SYM(rpnt->r_info);
+
+		debug_sym(symtab, strtab, symtab_index);
+		debug_reloc(symtab, strtab, rpnt);
+
+		res = reloc_fnc(tpnt, scope, rpnt, symtab, strtab);
+
+		if (res == 0)
+			continue;
+
+		_dl_dprintf(2, "\n%s: ", _dl_progname);
+
+		if (symtab_index)
+			_dl_dprintf(2, "symbol '%s': ",
+				    strtab + symtab[symtab_index].st_name);
+
+		if (unlikely(res < 0)) {
+			int reloc_type = ELF_R_TYPE(rpnt->r_info);
+
+			_dl_dprintf(2, "can't handle reloc type "
+#if defined (__SUPPORT_LD_DEBUG__)
+				    "%s\n", _dl_reltypes(reloc_type));
+#else
+				    "%x\n", reloc_type);
+#endif
+			_dl_exit(-res);
+		} else if (unlikely(res > 0)) {
+			_dl_dprintf(2, "can't resolve symbol\n");
+			return res;
+		}
+	}
+
+	return 0;
+}
+
+static int
+_dl_do_reloc(struct elf_resolve *tpnt, struct r_scope_elem *scope,
+	     ELF_RELOC *rpnt, ElfW(Sym) *symtab, char *strtab)
+{
+	int reloc_type;
+	int symtab_index;
+	char *symname;
+#if defined USE_TLS && USE_TLS
+	struct elf_resolve *tls_tpnt = NULL;
+#endif
+	struct symbol_ref sym_ref;
+	ElfW(Addr) *reloc_addr;
+	ElfW(Addr) symbol_addr;
+#if defined (__SUPPORT_LD_DEBUG__)
+	ElfW(Addr) old_val;
+#endif
+
+	reloc_addr = (ElfW(Addr)*)(tpnt->loadaddr + (unsigned long)rpnt->r_offset);
+	reloc_type = ELF_R_TYPE(rpnt->r_info);
+	symtab_index = ELF_R_SYM(rpnt->r_info);
+	sym_ref.sym = &symtab[symtab_index];
+	sym_ref.tpnt = NULL;
+	symbol_addr = 0;
+	symname = strtab + sym_ref.sym->st_name;
+
+	if (symtab_index) {
+		symbol_addr = (ElfW(Addr))_dl_find_hash(symname, scope, tpnt,
+				elf_machine_type_class(reloc_type), &sym_ref);
+		/*
+		 * We want to allow undefined references to weak symbols - this
+		 * might have been intentional.  We should not be linking local
+		 * symbols here, so all bases should be covered.
+		 */
+		if (unlikely(!symbol_addr && (ELF_ST_TYPE(sym_ref.sym->st_info) != STT_TLS)
+					&& (ELF_ST_BIND(sym_ref.sym->st_info) != STB_WEAK))) {
+			/* This may be non-fatal if called from dlopen. */
+			return 1;
+		}
+#if defined USE_TLS && USE_TLS
+		tls_tpnt = sym_ref.tpnt;
+#endif
+	} else {
+		/* Relocs against STN_UNDEF are usually treated as using a
+		 * symbol value of zero, and using the module containing the
+		 * reloc itself. */
+		symbol_addr = sym_ref.sym->st_value;
+#if defined USE_TLS && USE_TLS
+		tls_tpnt = tpnt;
+#endif
+	}
+
+
+#if defined (__SUPPORT_LD_DEBUG__)
+	if (reloc_addr) {
+		old_val = *reloc_addr;
+	} else {
+		old_val = 0;
+	}
+#endif
+
+	switch (reloc_type) {
+		case R_NIOS2_NONE:
+			break;
+
+		case R_NIOS2_BFD_RELOC_32:
+		case R_NIOS2_GLOB_DAT:
+		case R_NIOS2_JUMP_SLOT:
+			*reloc_addr = symbol_addr + rpnt->r_addend;
+			break;
+
+		case R_NIOS2_RELATIVE:
+			*reloc_addr = (unsigned long)tpnt->loadaddr + rpnt->r_addend;
+			break;
+
+		case R_NIOS2_COPY:
+			if (symbol_addr) {
+#if defined (__SUPPORT_LD_DEBUG__)
+				if (_dl_debug_move)
+					_dl_dprintf(_dl_debug_file,
+						    "\t%s move %d bytes from %x to %x\n",
+						    symname, sym_ref.sym->st_size,
+						    symbol_addr, reloc_addr);
+#endif
+
+				_dl_memcpy((char *)reloc_addr,
+					   (char *)symbol_addr,
+					   sym_ref.sym->st_size);
+			}
+			break;
+
+		default:
+			return -1;	/* Calls _dl_exit(1). */
+	}
+
+#if defined (__SUPPORT_LD_DEBUG__)
+	if (_dl_debug_reloc && _dl_debug_detail)
+		_dl_dprintf(_dl_debug_file, "\tpatched: %x ==> %x @ %x\n",
+			    old_val, *reloc_addr, reloc_addr);
+#endif
+
+	return 0;
+}
+
+static int
+_dl_do_lazy_reloc(struct elf_resolve *tpnt, struct r_scope_elem *scope,
+		  ELF_RELOC *rpnt, ElfW(Sym) *symtab, char *strtab)
+{
+	int reloc_type;
+	ElfW(Addr) *reloc_addr;
+#if defined (__SUPPORT_LD_DEBUG__)
+	ElfW(Addr) old_val;
+#endif
+
+	(void)scope;
+	(void)strtab;
+
+	reloc_addr = (ElfW(Addr)*)(tpnt->loadaddr + rpnt->r_offset);
+	reloc_type = ELF_R_TYPE(rpnt->r_info);
+
+#if defined (__SUPPORT_LD_DEBUG__)
+	old_val = *reloc_addr;
+#endif
+
+	switch (reloc_type) {
+		case R_NIOS2_NONE:
+			break;
+		case R_NIOS2_JUMP_SLOT:
+			*reloc_addr += (unsigned long)tpnt->loadaddr;
+			break;
+		default:
+			_dl_exit(1);
+	}
+
+#if defined (__SUPPORT_LD_DEBUG__)
+	if (_dl_debug_reloc && _dl_debug_detail)
+		_dl_dprintf(_dl_debug_file, "\tpatched_lazy: %x ==> %x @ %x\n",
+			    old_val, *reloc_addr, reloc_addr);
+#endif
+
+	return 0;
+}
+
+void
+_dl_parse_lazy_relocation_information(struct dyn_elf *rpnt,
+	unsigned long rel_addr, unsigned long rel_size)
+{
+	(void)_dl_parse(rpnt->dyn, NULL, rel_addr, rel_size, _dl_do_lazy_reloc);
+}
+
+int
+_dl_parse_relocation_information(struct dyn_elf *rpnt,
+	struct r_scope_elem *scope, unsigned long rel_addr, unsigned long rel_size)
+{
+	return _dl_parse(rpnt->dyn, scope, rel_addr, rel_size, _dl_do_reloc);
+}
diff --git a/ldso/ldso/nios2/resolve.S b/ldso/ldso/nios2/resolve.S
new file mode 100644
index 000000000..a71839e17
--- /dev/null
+++ b/ldso/ldso/nios2/resolve.S
@@ -0,0 +1,73 @@
+/* PLT trampolines.  Nios II version.
+   Copyright (C) 2005-2016 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
+   <http://www.gnu.org/licenses/>.  */
+
+/* This code is used in dl-runtime.c to call the `fixup' function
+   and then redirect to the address it returns. */
+
+	.text
+	.align 4
+	.globl _dl_linux_resolver
+	.globl _dl_linux_resolve
+	.type  _dl_linux_resolve,@function
+
+_dl_linux_resolve:
+/* The runtime resolver receives the original function arguments in r4
+   through r7, the shared library identifier from GOT[1]? in r14, and the
+   relocation index times four in r15. It updates the corresponding PLT GOT
+   entry so that the PLT entry will transfer control directly to the target
+   in the future, and then transfers control to the target. */
+	/* Save arguments and return address.  */
+	subi sp, sp, 28
+	stw r22, 24(sp)
+	stw r8, 20(sp)  /* save r8, because this might be a call to mcount */
+	stw r7, 16(sp)
+	stw r6, 12(sp)
+	stw r5, 8(sp)
+	stw r4, 4(sp)
+	stw ra, 0(sp)
+
+	/* Get pointer to linker struct.  */
+	mov r4, r14
+
+	/* Get the relocation offset.  We're given a multiple of 4 and
+	   need a multiple of 12, so multiply by 3. */
+	slli r5, r15, 1
+	add r5, r5, r15
+
+	/* Call the fixup routine.  */
+	nextpc r22
+1:	movhi r2, %hiadj(_gp_got - 1b)
+	addi r2, r2, %lo(_gp_got - 1b)
+	add r22, r22, r2
+	ldw r2, %call(_dl_linux_resolver)(r22)
+	callr r2
+
+	/* Restore the arguments and return address.  */
+	ldw ra, 0(sp)
+	ldw r4, 4(sp)
+	ldw r5, 8(sp)
+	ldw r6, 12(sp)
+	ldw r7, 16(sp)
+	ldw r8, 20(sp)
+	ldw r22, 24(sp)
+	addi sp, sp, 28
+
+	/* Jump to the newly found address.  */
+	jmp r2
+
+    .size _dl_linux_resolve, . - _dl_linux_resolve