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authorWaldemar Brodkorb <wbx@openadk.org>2016-05-28 18:12:58 +0200
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2016-11-04 00:03:07 +0100
commitb8fcdddcbb192fc367ff04bbd753b9deb69b09f3 (patch)
tree8febdb9d4e3d090e9273c29df9ff06116196c8e4 /ldso
parent191739597c6d380692885cfdd8dd8aa4f31f029d (diff)
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.
Diffstat (limited to 'ldso')
-rw-r--r--ldso/ldso/nios2/dl-debug.h18
-rw-r--r--ldso/ldso/nios2/dl-inlines.h12
-rw-r--r--ldso/ldso/nios2/dl-startup.h34
-rw-r--r--ldso/ldso/nios2/dl-syscalls.h1
-rw-r--r--ldso/ldso/nios2/dl-sysdep.h74
-rw-r--r--ldso/ldso/nios2/elfinterp.c297
-rw-r--r--ldso/ldso/nios2/resolve.S73
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