435 lines
13 KiB
C
435 lines
13 KiB
C
/* Machine-dependent ELF dynamic relocation inline functions.
|
|
64 bit S/390 Version.
|
|
Copyright (C) 2001 Free Software Foundation, Inc.
|
|
Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
|
|
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 Library General Public License as
|
|
published by the Free Software Foundation; either version 2 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
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If
|
|
not, write to the Free Software Foundation, Inc.,
|
|
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
|
|
|
|
#ifndef dl_machine_h
|
|
#define dl_machine_h
|
|
|
|
#define ELF_MACHINE_NAME "s390x"
|
|
|
|
#include <sys/param.h>
|
|
#include <string.h>
|
|
#include <link.h>
|
|
|
|
/* This is an older, now obsolete value. */
|
|
#define EM_S390_OLD 0xA390
|
|
|
|
/* Return nonzero iff E_MACHINE is compatible with the running host. */
|
|
static inline int
|
|
elf_machine_matches_host (const Elf64_Ehdr *ehdr)
|
|
{
|
|
return (ehdr->e_machine == EM_S390 || ehdr->e_machine == EM_S390_OLD)
|
|
&& ehdr->e_ident[EI_CLASS] == ELFCLASS64;
|
|
}
|
|
|
|
/* Return the link-time address of _DYNAMIC. Conveniently, this is the
|
|
first element of the GOT. This must be inlined in a function which
|
|
uses global data. */
|
|
|
|
static inline Elf64_Addr
|
|
elf_machine_dynamic (void)
|
|
{
|
|
register Elf64_Addr *got;
|
|
|
|
asm( " larl %0,_GLOBAL_OFFSET_TABLE_\n"
|
|
: "=&a" (got) : : "0" );
|
|
|
|
return *got;
|
|
}
|
|
|
|
/* Return the run-time load address of the shared object. */
|
|
static inline Elf64_Addr
|
|
elf_machine_load_address (void)
|
|
{
|
|
Elf64_Addr addr;
|
|
|
|
asm( " larl %0,_dl_start\n"
|
|
" larl 1,_GLOBAL_OFFSET_TABLE_\n"
|
|
" lghi 2,_dl_start@GOT\n"
|
|
" slg %0,0(2,1)"
|
|
: "=&d" (addr) : : "1", "2" );
|
|
return addr;
|
|
}
|
|
|
|
/* Set up the loaded object described by L so its unrelocated PLT
|
|
entries will jump to the on-demand fixup code in dl-runtime.c. */
|
|
|
|
static inline int __attribute__ ((unused))
|
|
elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
|
|
{
|
|
extern void _dl_runtime_resolve (Elf64_Word);
|
|
extern void _dl_runtime_profile (Elf64_Word);
|
|
|
|
if (l->l_info[DT_JMPREL] && lazy)
|
|
{
|
|
/* The GOT entries for functions in the PLT have not yet been filled
|
|
in. Their initial contents will arrange when called to push an
|
|
offset into the .rela.plt section, push _GLOBAL_OFFSET_TABLE_[1],
|
|
and then jump to _GLOBAL_OFFSET_TABLE[2]. */
|
|
Elf64_Addr *got;
|
|
got = (Elf64_Addr *) D_PTR (l, l_info[DT_PLTGOT]);
|
|
got[1] = (Elf64_Addr) l; /* Identify this shared object. */
|
|
|
|
/* The got[2] entry contains the address of a function which gets
|
|
called to get the address of a so far unresolved function and
|
|
jump to it. The profiling extension of the dynamic linker allows
|
|
to intercept the calls to collect information. In this case we
|
|
don't store the address in the GOT so that all future calls also
|
|
end in this function. */
|
|
if (__builtin_expect (profile, 0))
|
|
{
|
|
got[2] = (Elf64_Addr) &_dl_runtime_profile;
|
|
|
|
if (_dl_name_match_p (_dl_profile, l))
|
|
/* This is the object we are looking for. Say that we really
|
|
want profiling and the timers are started. */
|
|
_dl_profile_map = l;
|
|
}
|
|
else
|
|
/* This function will get called to fix up the GOT entry indicated by
|
|
the offset on the stack, and then jump to the resolved address. */
|
|
got[2] = (Elf64_Addr) &_dl_runtime_resolve;
|
|
}
|
|
|
|
return lazy;
|
|
}
|
|
|
|
/* This code is used in dl-runtime.c to call the `fixup' function
|
|
and then redirect to the address it returns. */
|
|
|
|
/* s390:
|
|
Arguments are in register.
|
|
r2 - r7 holds the original parameters for the function call, fixup
|
|
and trampoline code use r0-r5 and r14-15. For the correct function
|
|
call r2-r5 and r14-15 must be restored.
|
|
Arguments from the PLT are stored at 48(r15) and 56(r15)
|
|
and must be moved to r2 and r3 for the fixup call (see elf32-s390.c
|
|
in the binutils for the PLT code).
|
|
Fixup function address in r2.
|
|
*/
|
|
#ifndef PROF
|
|
#define ELF_MACHINE_RUNTIME_TRAMPOLINE \
|
|
asm ( "\
|
|
.text\n\
|
|
.globl _dl_runtime_resolve\n\
|
|
.type _dl_runtime_resolve, @function\n\
|
|
.align 16\n\
|
|
_dl_runtime_resolve:\n\
|
|
# save registers\n\
|
|
stmg 2,5,64(15)\n\
|
|
stg 14,96(15)\n\
|
|
lgr 0,15\n\
|
|
aghi 15,-160\n\
|
|
stg 0,0(15)\n\
|
|
# load args saved by PLT\n\
|
|
lmg 2,3,208(15)\n\
|
|
brasl 14,fixup # call fixup
|
|
lgr 1,2 # function addr returned in r2\n\
|
|
# restore registers\n\
|
|
aghi 15,160\n\
|
|
lg 14,96(15)\n\
|
|
lmg 2,5,64(15)\n\
|
|
br 1\n\
|
|
.size _dl_runtime_resolve, .-_dl_runtime_resolve\n\
|
|
\n\
|
|
.globl _dl_runtime_profile\n\
|
|
.type _dl_runtime_profile, @function\n\
|
|
.align 16\n\
|
|
_dl_runtime_profile:\n\
|
|
# save registers\n\
|
|
stmg 2,5,64(15)\n\
|
|
stg 14,96(15)\n\
|
|
lgr 0,15\n\
|
|
aghi 15,-160\n\
|
|
stg 0,0(15)\n\
|
|
# load args saved by PLT\n\
|
|
lmg 2,3,208(15)\n\
|
|
# load return address as third parameter\n\
|
|
lgr 4,14\n\
|
|
brasl 14,profile_fixup # call fixup\n\
|
|
lgr 1,2 # function addr returned in r2\n\
|
|
# restore registers\n\
|
|
aghi 15,160\n\
|
|
lg 14,96(15)\n\
|
|
lmg 2,5,64(15)\n\
|
|
br 1\n\
|
|
.size _dl_runtime_profile, .-_dl_runtime_profile\n\
|
|
");
|
|
#else
|
|
#define ELF_MACHINE_RUNTIME_TRAMPOLINE \
|
|
asm ( "\
|
|
.text\n\
|
|
.globl _dl_runtime_resolve\n\
|
|
.globl _dl_runtime_profile\n\
|
|
.type _dl_runtime_resolve, @function\n\
|
|
.type _dl_runtime_profile, @function\n\
|
|
.align 16\n\
|
|
_dl_runtime_resolve:\n\
|
|
_dl_runtime_profile:\n\
|
|
# save registers\n\
|
|
stmg 2,5,64(15)\n\
|
|
stg 14,96(15)\n\
|
|
lgr 0,15\n\
|
|
aghi 15,-160\n\
|
|
stg 0,0(15)\n\
|
|
# load args saved by PLT\n\
|
|
lmg 2,3,208(15)\n\
|
|
# load return address as third parameter\n\
|
|
lgr 4,14\n\
|
|
brasl 14,profile_fixup # call fixup\n\
|
|
lgr 1,2 # function addr returned in r2\n\
|
|
# restore registers\n\
|
|
aghi 15,160\n\
|
|
lg 14,96(15)\n\
|
|
lmg 2,5,64(15)\n\
|
|
br 1\n\
|
|
.size _dl_runtime_resolve, .-_dl_runtime_resolve\n\
|
|
.size _dl_runtime_profile, .-_dl_runtime_profile\n\
|
|
");
|
|
#endif
|
|
|
|
/* Initial entry point code for the dynamic linker.
|
|
The C function `_dl_start' is the real entry point;
|
|
its return value is the user program's entry point. */
|
|
|
|
#define RTLD_START asm ("\n\
|
|
.text\n\
|
|
.align 4\n\
|
|
.globl _start\n\
|
|
.globl _dl_start_user\n\
|
|
_start:\n\
|
|
lgr %r2,%r15\n\
|
|
# Alloc stack frame\n\
|
|
aghi %r15,-160\n\
|
|
# Set the back chain to zero\n\
|
|
xc 0(8,%r15),0(%r15)\n\
|
|
# Call _dl_start with %r2 pointing to arg on stack\n\
|
|
brasl %r14,_dl_start # call _dl_start\n\
|
|
_dl_start_user:\n\
|
|
# Save the user entry point address in %r8.\n\
|
|
lgr %r8,%r2\n\
|
|
# Point %r12 at the GOT.\n\
|
|
larl %r12,_GLOBAL_OFFSET_TABLE_\n\
|
|
# Store the highest stack address\n\
|
|
lghi %r1,__libc_stack_end@GOT
|
|
lg %r1,0(%r1,%r12)\n\
|
|
stg %r15, 0(%r1)\n\
|
|
# See if we were run as a command with the executable file\n\
|
|
# name as an extra leading argument.\n\
|
|
lghi %r1,_dl_skip_args@GOT
|
|
lg %r1,0(%r1,%r12)\n\
|
|
lgf %r1,0(%r1) # load _dl_skip_args\n\
|
|
# Get the original argument count.\n\
|
|
lg %r0,160(%r15)\n\
|
|
# Subtract _dl_skip_args from it.\n\
|
|
sgr %r0,%r1\n\
|
|
# Adjust the stack pointer to skip _dl_skip_args words.\n\
|
|
sllg %r1,%r1,3\n\
|
|
agr %r15,%r1\n\
|
|
# Set the back chain to zero again\n\
|
|
xc 0(8,%r15),0(%r15)\n\
|
|
# Store back the modified argument count.\n\
|
|
stg %r0,160(%r15)\n\
|
|
# The special initializer gets called with the stack just\n\
|
|
# as the application's entry point will see it; it can\n\
|
|
# switch stacks if it moves these contents over.\n\
|
|
" RTLD_START_SPECIAL_INIT "\n\
|
|
# Call the function to run the initializers.\n\
|
|
# Load the parameters:\n\
|
|
# (%r2, %r3, %r4, %r5) = (_dl_loaded, argc, argv, envp)\n\
|
|
lghi %r2,_dl_loaded@GOT
|
|
lg %r2,0(%r2,%r12)\n\
|
|
lg %r2,0(%r2)\n\
|
|
lg %r3,160(%r15)\n\
|
|
la %r4,168(%r15)\n\
|
|
lgr %r5,%r3\n\
|
|
sllg %r5,%r5,3\n\
|
|
la %r5,176(%r5,%r15)\n\
|
|
brasl %r14,_dl_init@PLT\n
|
|
# Pass our finalizer function to the user in %r14, as per ELF ABI.\n\
|
|
lghi %r14,_dl_fini@GOT
|
|
lg %r14,0(%r14,%r12)\n\
|
|
# Free stack frame\n\
|
|
aghi %r15,160\n\
|
|
# Jump to the user's entry point (saved in %r8).\n\
|
|
br %r8\n\
|
|
");
|
|
|
|
#ifndef RTLD_START_SPECIAL_INIT
|
|
#define RTLD_START_SPECIAL_INIT /* nothing */
|
|
#endif
|
|
|
|
/* Nonzero iff TYPE should not be allowed to resolve to one of
|
|
the main executable's symbols, as for a COPY reloc. */
|
|
#define elf_machine_lookup_noexec_p(type) ((type) == R_390_COPY)
|
|
|
|
/* Nonzero iff TYPE describes relocation of a PLT entry, so
|
|
PLT entries should not be allowed to define the value. */
|
|
#define elf_machine_lookup_noplt_p(type) ((type) == R_390_JMP_SLOT)
|
|
|
|
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
|
|
#define ELF_MACHINE_JMP_SLOT R_390_JMP_SLOT
|
|
|
|
/* The 64 bit S/390 never uses Elf64_Rel relocations. */
|
|
#define ELF_MACHINE_NO_REL 1
|
|
|
|
/* We define an initialization functions. This is called very early in
|
|
_dl_sysdep_start. */
|
|
#define DL_PLATFORM_INIT dl_platform_init ()
|
|
|
|
extern const char *_dl_platform;
|
|
|
|
static inline void __attribute__ ((unused))
|
|
dl_platform_init (void)
|
|
{
|
|
if (_dl_platform != NULL && *_dl_platform == '\0')
|
|
/* Avoid an empty string which would disturb us. */
|
|
_dl_platform = NULL;
|
|
}
|
|
|
|
static inline Elf64_Addr
|
|
elf_machine_fixup_plt (struct link_map *map, lookup_t t,
|
|
const Elf64_Rela *reloc,
|
|
Elf64_Addr *reloc_addr, Elf64_Addr value)
|
|
{
|
|
return *reloc_addr = value;
|
|
}
|
|
|
|
/* Return the final value of a plt relocation. */
|
|
static inline Elf64_Addr
|
|
elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc,
|
|
Elf64_Addr value)
|
|
{
|
|
return value;
|
|
}
|
|
|
|
#endif /* !dl_machine_h */
|
|
|
|
#ifdef RESOLVE
|
|
|
|
/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
|
|
MAP is the object containing the reloc. */
|
|
|
|
static inline void
|
|
elf_machine_rela (struct link_map *map, const Elf64_Rela *reloc,
|
|
const Elf64_Sym *sym, const struct r_found_version *version,
|
|
Elf64_Addr *const reloc_addr)
|
|
{
|
|
if (ELF64_R_TYPE (reloc->r_info) == R_390_RELATIVE) {
|
|
#ifndef RTLD_BOOTSTRAP
|
|
weak_extern (_dl_rtld_map);
|
|
if (map != &_dl_rtld_map) /* Already done in rtld itself. */
|
|
#endif
|
|
*reloc_addr = map->l_addr + reloc->r_addend;
|
|
}
|
|
else if (ELF64_R_TYPE (reloc->r_info) != R_390_NONE)
|
|
{
|
|
const Elf64_Sym *const refsym = sym;
|
|
Elf64_Addr value = RESOLVE (&sym, version, ELF64_R_TYPE (reloc->r_info));
|
|
if (sym)
|
|
value += sym->st_value;
|
|
|
|
switch (ELF64_R_TYPE (reloc->r_info))
|
|
{
|
|
case R_390_GLOB_DAT:
|
|
case R_390_JMP_SLOT:
|
|
*reloc_addr = value + reloc->r_addend;
|
|
break;
|
|
#ifndef RTLD_BOOTSTRAP
|
|
case R_390_COPY:
|
|
if (sym == NULL)
|
|
/* This can happen in trace mode if an object could not be
|
|
found. */
|
|
break;
|
|
if (__builtin_expect (sym->st_size > refsym->st_size, 0)
|
|
|| (__builtin_expect (sym->st_size < refsym->st_size, 0)
|
|
&& __builtin_expect (_dl_verbose, 0)))
|
|
{
|
|
const char *strtab;
|
|
|
|
strtab = (const char *) D_PTR (map,l_info[DT_STRTAB]);
|
|
_dl_error_printf ("\
|
|
%s: Symbol `%s' has different size in shared object, consider re-linking\n",
|
|
_dl_argv[0] ?: "<program name unknown>",
|
|
strtab + refsym->st_name);
|
|
}
|
|
memcpy (reloc_addr, (void *) value, MIN (sym->st_size,
|
|
refsym->st_size));
|
|
break;
|
|
case R_390_64:
|
|
*reloc_addr = value + reloc->r_addend;
|
|
break;
|
|
case R_390_32:
|
|
*(unsigned int *) reloc_addr = value + reloc->r_addend;
|
|
break;
|
|
case R_390_16:
|
|
*(unsigned short *) reloc_addr = value + reloc->r_addend;
|
|
break;
|
|
case R_390_8:
|
|
*(char *) reloc_addr = value + reloc->r_addend;
|
|
break;
|
|
case R_390_PC64:
|
|
*reloc_addr = value +reloc->r_addend - (Elf64_Addr) reloc_addr;
|
|
break;
|
|
case R_390_PC32DBL:
|
|
case R_390_PLT32DBL:
|
|
*(unsigned int *) reloc_addr = (unsigned int)
|
|
((int) (value + reloc->r_addend - (Elf64_Addr) reloc_addr) >> 1);
|
|
break;
|
|
case R_390_PC32:
|
|
*(unsigned int *) reloc_addr =
|
|
value + reloc->r_addend - (Elf64_Addr) reloc_addr;
|
|
break;
|
|
case R_390_PC16DBL:
|
|
case R_390_PLT16DBL:
|
|
*(unsigned short *) reloc_addr = (unsigned short)
|
|
((short) (value + reloc->r_addend - (Elf64_Addr) reloc_addr) >> 1);
|
|
break;
|
|
case R_390_PC16:
|
|
*(unsigned short *) reloc_addr =
|
|
value + reloc->r_addend - (Elf64_Addr) reloc_addr;
|
|
break;
|
|
#endif
|
|
#if !defined(RTLD_BOOTSTRAP) || defined(_NDEBUG)
|
|
default:
|
|
/* We add these checks in the version to relocate ld.so only
|
|
if we are still debugging. */
|
|
_dl_reloc_bad_type (map, ELFW(R_TYPE) (reloc->r_info), 0);
|
|
break;
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
|
|
static inline void
|
|
elf_machine_lazy_rel (struct link_map *map,
|
|
Elf64_Addr l_addr, const Elf64_Rela *reloc)
|
|
{
|
|
Elf64_Addr *const reloc_addr = (void *) (l_addr + reloc->r_offset);
|
|
/* Check for unexpected PLT reloc type. */
|
|
if (__builtin_expect (ELF64_R_TYPE (reloc->r_info), R_390_JMP_SLOT)
|
|
== R_390_JMP_SLOT)
|
|
*reloc_addr += l_addr;
|
|
else
|
|
_dl_reloc_bad_type (map, ELFW(R_TYPE) (reloc->r_info), 1);
|
|
}
|
|
|
|
#endif /* RESOLVE */
|