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/* Machine-dependent ELF dynamic relocation.
Parts copied from glibc/sysdeps/xtensa/dl-machine.h
Copyright (C) 2001, 2007 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/>. */
/* Define this if the system uses RELOCA. */
#define ELF_USES_RELOCA
#include <elf.h>
#include <link.h>
/* Translate a processor specific dynamic tag to the index
in l_info array. */
#define DT_XTENSA(x) (DT_XTENSA_##x - DT_LOPROC + DT_NUM + OS_NUM)
typedef struct xtensa_got_location_struct {
Elf32_Off offset;
Elf32_Word length;
} xtensa_got_location;
/* Initialization sequence for the GOT. */
#define INIT_GOT(GOT_BASE, MODULE) \
do { \
xtensa_got_location *got_loc; \
Elf32_Addr l_addr = MODULE->loadaddr; \
int x; \
\
got_loc = (xtensa_got_location *) \
(MODULE->dynamic_info[DT_XTENSA (GOT_LOC_OFF)] + l_addr); \
\
for (x = 0; x < MODULE->dynamic_info[DT_XTENSA (GOT_LOC_SZ)]; x++) \
{ \
Elf32_Addr got_start, got_end; \
got_start = got_loc[x].offset & ~(PAGE_SIZE - 1); \
got_end = ((got_loc[x].offset + got_loc[x].length + PAGE_SIZE - 1) \
& ~(PAGE_SIZE - 1)); \
_dl_mprotect ((void *)(got_start + l_addr) , got_end - got_start, \
PROT_READ | PROT_WRITE | PROT_EXEC); \
} \
\
/* Fill in first GOT entry according to the ABI. */ \
GOT_BASE[0] = (unsigned long) _dl_linux_resolve; \
} while (0)
/* Parse dynamic info */
#define ARCH_NUM 2
#define ARCH_DYNAMIC_INFO(dpnt, dynamic, debug_addr) \
do { \
if (dpnt->d_tag == DT_XTENSA_GOT_LOC_OFF) \
dynamic[DT_XTENSA (GOT_LOC_OFF)] = dpnt->d_un.d_ptr; \
else if (dpnt->d_tag == DT_XTENSA_GOT_LOC_SZ) \
dynamic[DT_XTENSA (GOT_LOC_SZ)] = dpnt->d_un.d_val; \
} while (0)
/* Here we define the magic numbers that this dynamic loader should accept. */
#define MAGIC1 EM_XTENSA
#undef MAGIC2
/* Used for error messages. */
#define ELF_TARGET "Xtensa"
/* Need bootstrap relocations */
#define ARCH_NEEDS_BOOTSTRAP_RELOCS
struct elf_resolve;
extern unsigned long _dl_linux_resolver (struct elf_resolve *, int);
/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry, so
undefined references should not be allowed to define the value. */
#define elf_machine_type_class(type) \
(((type) == R_XTENSA_JMP_SLOT) * ELF_RTYPE_CLASS_PLT)
/* Return the link-time address of _DYNAMIC. */
static __always_inline Elf32_Addr
elf_machine_dynamic (void)
{
/* This function is only used while bootstrapping the runtime linker.
The "_DYNAMIC" symbol is always local so its GOT entry will initially
contain the link-time address. */
return (Elf32_Addr) &_DYNAMIC;
}
/* Return the run-time load address of the shared object. */
static __always_inline Elf32_Addr
elf_machine_load_address (void)
{
Elf32_Addr addr, tmp;
/* At this point, the runtime linker is being bootstrapped and the GOT
entry used for ".Lhere" will contain the link address. The CALL0 will
produce the dynamic address of ".Lhere" + 3. Thus, the end result is
equal to "dynamic_address(.Lhere) - link_address(.Lhere)". */
__asm__ ("\
movi %0, .Lhere\n\
mov %1, a0\n\
.Lhere: _call0 0f\n\
.align 4\n\
0: sub %0, a0, %0\n\
mov a0, %1"
: "=a" (addr), "=a" (tmp));
return addr - 3;
}
static __always_inline void
elf_machine_relative (Elf32_Addr load_off, const Elf32_Addr rel_addr,
Elf32_Word relative_count)
{
Elf32_Rela *rpnt = (Elf32_Rela *) rel_addr;
while (relative_count--)
{
Elf32_Addr *const reloc_addr = (Elf32_Addr *) (load_off + rpnt->r_offset);
*reloc_addr += load_off + rpnt->r_addend;
rpnt++;
}
}
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