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Diffstat (limited to 'sysdeps/or1k/dl-machine.h')
| -rw-r--r-- | sysdeps/or1k/dl-machine.h | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/sysdeps/or1k/dl-machine.h b/sysdeps/or1k/dl-machine.h new file mode 100644 index 0000000..35329a6 --- /dev/null +++ b/sysdeps/or1k/dl-machine.h @@ -0,0 +1,300 @@ +/* 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 + { +# ifndef RESOLVE_CONFLICT_FIND_MAP + const Elf32_Sym *const refsym = sym; +# endif + 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) + { +# ifndef RESOLVE_CONFLICT_FIND_MAP + 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; +# endif /* !RESOLVE_CONFLICT_FIND_MAP */ + 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 */ |