ubuntu-buildroot/output/build/glibc-2.36-81-g4f4d7a13edfd.../sysdeps/or1k/dl-machine.h

297 lines
8.8 KiB
C

/* Machine-dependent ELF dynamic relocation inline functions. OpenRISC version.
Copyright (C) 2022 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
<https://www.gnu.org/licenses/>. */
#ifndef dl_machine_h
#define dl_machine_h
#define ELF_MACHINE_NAME "or1k"
#include <sys/cdefs.h>
#include <sys/param.h>
#include <tls.h>
#include <dl-irel.h>
#include <dl-static-tls.h>
#include <dl-machine-rel.h>
/* Return nonzero iff ELF header is compatible with the running host. */
static inline int __attribute__ ((unused))
elf_machine_matches_host (const Elf32_Ehdr *ehdr)
{
return ehdr->e_machine == EM_OPENRISC;
}
static inline Elf32_Addr *
or1k_get_got (void)
{
Elf32_Addr *got;
asm ("l.jal 0x8\n"
" l.movhi %0, gotpchi(_GLOBAL_OFFSET_TABLE_-4)\n"
"l.ori %0, %0, gotpclo(_GLOBAL_OFFSET_TABLE_+0)\n"
"l.add %0, %0, r9\n"
: "=r" (got) : : "r9");
return got;
}
/* 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 *got = or1k_get_got ();
return *got;
}
/* Return the run-time load address of the shared object. */
static inline Elf32_Addr
elf_machine_load_address (void)
{
/* Compute the difference between the runtime address of _DYNAMIC as seen
by a GOTOFF reference, and the link-time address found in the special
unrelocated first GOT entry. */
Elf32_Addr dyn;
Elf32_Addr *got = or1k_get_got ();
asm ("l.movhi %0, gotoffhi(_DYNAMIC);"
"l.ori %0, %0, gotofflo(_DYNAMIC);"
"l.add %0, %0, %1;"
: "=&r"(dyn) : "r"(got));
return dyn - *got;
}
/* Initial entry point code for the dynamic linker. The function _dl_start
is the real entry point; it's return value is the user program's entry
point.
Code is really located in dl-start.S, just tell the linker that it
exists. */
#define RTLD_START asm (".globl _dl_start");
/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry or
TLS variable, so undefined references should not be allowed to
define the value.
ELF_RTYPE_CLASS_NOCOPY 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_OR1K_JMP_SLOT \
|| (type) == R_OR1K_TLS_DTPMOD \
|| (type) == R_OR1K_TLS_DTPOFF \
|| (type) == R_OR1K_TLS_TPOFF) * ELF_RTYPE_CLASS_PLT \
| ((type) == R_OR1K_COPY) * ELF_RTYPE_CLASS_COPY)
/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */
#define ELF_MACHINE_JMP_SLOT R_OR1K_JMP_SLOT
#define ARCH_LA_PLTENTER or1k_gnu_pltenter
#define ARCH_LA_PLTEXIT or1k_gnu_pltexit
/* 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, always_inline))
elf_machine_runtime_setup (struct link_map *l, struct r_scope_elem *scope[],
int lazy, int profile)
{
ElfW(Addr) *pltgot;
extern void _dl_runtime_resolve (ElfW(Word));
extern void _dl_runtime_profile (ElfW(Word));
if (l->l_info[DT_JMPREL] && lazy)
{
pltgot = (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]);
/* Fill in initial entrys of the plt */
/* Register the link_map address in the plt at pltgot[1].
This will also be used in the resolver for accessing the
link_map structure. */
pltgot[1] = (ElfW(Addr)) l;
/* This function will get called to fix up the GOT entry and
then jump to the resolved address. */
pltgot[2] = (ElfW(Addr)) &_dl_runtime_resolve;
}
return lazy;
}
/* Mask identifying addresses reserved for the user program,
where the dynamic linker should not map anything. */
#define ELF_MACHINE_USER_ADDRESS_MASK 0xf8000000UL
/* We define an initialization functions. This is called very early in
_dl_sysdep_start. */
#define DL_PLATFORM_INIT dl_platform_init ()
static inline void __attribute__ ((unused))
dl_platform_init (void)
{
if (GLRO(dl_platform) != NULL && *GLRO(dl_platform) == '\0')
/* Avoid an empty string which would disturb us. */
GLRO(dl_platform) = NULL;
}
static inline ElfW(Addr)
elf_machine_fixup_plt (struct link_map *map, lookup_t t,
const ElfW(Sym) *refsym, const ElfW(Sym) *sym,
const ElfW(Rela) *reloc,
ElfW(Addr) *reloc_addr, ElfW(Addr) value)
{
return *reloc_addr = value;
}
/* Return the final value of a plt relocation. */
static inline Elf32_Addr
elf_machine_plt_value (struct link_map *map, const Elf32_Rela *reloc,
Elf32_Addr value)
{
return value + reloc->r_addend;
}
#endif /* !dl_machine_h */
#ifdef RESOLVE_MAP
/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
MAP is the object containing the reloc. */
static inline void
__attribute ((always_inline))
elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
const ElfW(Rela) *reloc, const ElfW(Sym) *sym,
const struct r_found_version *version,
void *const reloc_addr_arg, int skip_ifunc)
{
Elf32_Addr *const reloc_addr = reloc_addr_arg;
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
if (__glibc_unlikely (r_type == R_OR1K_NONE))
return;
else
{
const Elf32_Sym *const refsym = sym;
struct link_map *sym_map = RESOLVE_MAP (map, scope, &sym, version,
r_type);
Elf32_Addr value = SYMBOL_ADDRESS (sym_map, sym, true);
if (sym != NULL
&& __glibc_unlikely (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC)
&& __glibc_likely (sym->st_shndx != SHN_UNDEF)
&& __glibc_likely (!skip_ifunc))
value = elf_ifunc_invoke (value);
switch (r_type)
{
case R_OR1K_COPY:
if (sym == NULL)
/* This can happen in trace mode if an object could not be
found. */
break;
if (__glibc_unlikely (sym->st_size > refsym->st_size)
|| (__glibc_unlikely (sym->st_size < refsym->st_size)
&& GLRO(dl_verbose)))
{
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",
rtld_progname ?: "<program name unknown>",
strtab + refsym->st_name);
}
memcpy (reloc_addr_arg, (void *) value,
MIN (sym->st_size, refsym->st_size));
break;
case R_OR1K_32:
/* Support relocations on mis-aligned offsets. */
value += reloc->r_addend;
memcpy (reloc_addr_arg, &value, 4);
break;
case R_OR1K_GLOB_DAT:
case R_OR1K_JMP_SLOT:
*reloc_addr = value + reloc->r_addend;
break;
case R_OR1K_TLS_DTPMOD:
# ifdef RTLD_BOOTSTRAP
/* During startup the dynamic linker is always the module
with index 1. */
*reloc_addr = 1;
# else
if (sym_map != NULL)
*reloc_addr = sym_map->l_tls_modid;
# endif
break;
case R_OR1K_TLS_DTPOFF:
# ifndef RTLD_BOOTSTRAP
*reloc_addr = (sym == NULL ? 0 : sym->st_value) + reloc->r_addend;
# endif
break;
case R_OR1K_TLS_TPOFF:
# ifdef RTLD_BOOTSTRAP
*reloc_addr = sym->st_value + reloc->r_addend +
map->l_tls_offset - TLS_TCB_SIZE;
# else
if (sym_map != NULL)
{
CHECK_STATIC_TLS (map, sym_map);
*reloc_addr = sym->st_value + reloc->r_addend +
sym_map->l_tls_offset - TLS_TCB_SIZE;
}
# endif
break;
default:
_dl_reloc_bad_type (map, r_type, 0);
break;
}
}
}
static inline void
__attribute__ ((always_inline))
elf_machine_rela_relative (Elf32_Addr l_addr, const Elf32_Rela *reloc,
void *const reloc_addr_arg)
{
Elf32_Addr *const reloc_addr = reloc_addr_arg;
*reloc_addr = l_addr + reloc->r_addend;
}
static inline void
__attribute__ ((always_inline))
elf_machine_lazy_rel (struct link_map *map, struct r_scope_elem *scope[],
ElfW(Addr) l_addr, const ElfW(Rela) *reloc,
int skip_ifunc)
{
Elf32_Addr *const reloc_addr = (void *) (l_addr + reloc->r_offset);
const unsigned int r_type = ELF32_R_TYPE (reloc->r_info);
if (__glibc_likely (r_type == R_OR1K_JMP_SLOT))
*reloc_addr += l_addr;
else if (__glibc_unlikely (r_type == R_OR1K_NONE))
return;
else
_dl_reloc_bad_type (map, r_type, 1);
}
#endif /* RESOLVE_MAP */