1 /* Machine-dependent ELF dynamic relocation.
2 Parts copied from glibc/sysdeps/xtensa/dl-machine.h
3 Copyright (C) 2001, 2007 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
20 /* Define this if the system uses RELOCA. */
21 #define ELF_USES_RELOCA
25 /* Translate a processor specific dynamic tag to the index
27 #define DT_XTENSA(x) (DT_XTENSA_##x - DT_LOPROC + DT_NUM + OS_NUM)
29 typedef struct xtensa_got_location_struct {
32 } xtensa_got_location;
34 /* Initialization sequence for the GOT. */
35 #define INIT_GOT(GOT_BASE, MODULE) \
37 xtensa_got_location *got_loc; \
38 Elf32_Addr l_addr = MODULE->loadaddr; \
41 got_loc = (xtensa_got_location *) \
42 (MODULE->dynamic_info[DT_XTENSA (GOT_LOC_OFF)] + l_addr); \
44 for (x = 0; x < MODULE->dynamic_info[DT_XTENSA (GOT_LOC_SZ)]; x++) \
46 Elf32_Addr got_start, got_end; \
47 got_start = got_loc[x].offset & ~(PAGE_SIZE - 1); \
48 got_end = ((got_loc[x].offset + got_loc[x].length + PAGE_SIZE - 1) \
49 & ~(PAGE_SIZE - 1)); \
50 _dl_mprotect ((void *)(got_start + l_addr) , got_end - got_start, \
51 PROT_READ | PROT_WRITE | PROT_EXEC); \
54 /* Fill in first GOT entry according to the ABI. */ \
55 GOT_BASE[0] = (unsigned long) _dl_linux_resolve; \
58 /* Parse dynamic info */
60 #define ARCH_DYNAMIC_INFO(dpnt, dynamic, debug_addr) \
62 if (dpnt->d_tag == DT_XTENSA_GOT_LOC_OFF) \
63 dynamic[DT_XTENSA (GOT_LOC_OFF)] = dpnt->d_un.d_ptr; \
64 else if (dpnt->d_tag == DT_XTENSA_GOT_LOC_SZ) \
65 dynamic[DT_XTENSA (GOT_LOC_SZ)] = dpnt->d_un.d_val; \
68 /* Here we define the magic numbers that this dynamic loader should accept. */
69 #define MAGIC1 EM_XTENSA
72 /* Used for error messages. */
73 #define ELF_TARGET "Xtensa"
75 /* Need bootstrap relocations */
76 #define ARCH_NEEDS_BOOTSTRAP_RELOCS
79 extern unsigned long _dl_linux_resolver (struct elf_resolve *, int);
81 /* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry, so
82 undefined references should not be allowed to define the value. */
83 #define elf_machine_type_class(type) \
84 (((type) == R_XTENSA_JMP_SLOT) * ELF_RTYPE_CLASS_PLT)
86 /* Return the link-time address of _DYNAMIC. */
87 static __always_inline Elf32_Addr
88 elf_machine_dynamic (void)
90 /* This function is only used while bootstrapping the runtime linker.
91 The "_DYNAMIC" symbol is always local so its GOT entry will initially
92 contain the link-time address. */
93 return (Elf32_Addr) &_DYNAMIC;
96 /* Return the run-time load address of the shared object. */
97 static __always_inline Elf32_Addr
98 elf_machine_load_address (void)
100 Elf32_Addr addr, tmp;
102 /* At this point, the runtime linker is being bootstrapped and the GOT
103 entry used for ".Lhere" will contain the link address. The CALL0 will
104 produce the dynamic address of ".Lhere" + 3. Thus, the end result is
105 equal to "dynamic_address(.Lhere) - link_address(.Lhere)". */
113 : "=a" (addr), "=a" (tmp));
118 static __always_inline void
119 elf_machine_relative (Elf32_Addr load_off, const Elf32_Addr rel_addr,
120 Elf32_Word relative_count)
122 Elf32_Rela *rpnt = (Elf32_Rela *) rel_addr;
123 while (relative_count--)
125 Elf32_Addr *const reloc_addr = (Elf32_Addr *) (load_off + rpnt->r_offset);
126 *reloc_addr += load_off + rpnt->r_addend;