diff options
| -rw-r--r-- | ChangeLog | 22 | ||||
| -rw-r--r-- | sysdeps/mips/dl-machine.h | 221 | ||||
| -rw-r--r-- | sysdeps/mips/mips64/dl-machine.h | 594 |
3 files changed, 181 insertions, 656 deletions
diff --git a/ChangeLog b/ChangeLog index 5e418299aa..5c8bcab4f8 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,27 @@ 2003-03-14 Alexandre Oliva <aoliva@redhat.com> + * sysdeps/mips/dl-machine.h: Include sys/asm.h. + (elf_machine_matches_host): Prevent linking of o32 and n32 + together. + (elf_machine_dynamic): Document assumption on $gp. + (STRINGXP, STRINGXV, STRINGV_): New macros. + (elf_machine_load_address): Use them to stringize PTR_LA and + PTR_SUBU. + (ELF_DL_FRAME_SIZE, ELF_DL_SAVE_ARG_REGS, + ELF_DL_RESTORE_ARG_REGS, IFABIO32): New macros used in... + (_dl_runtime_resolve): Adjust it for all 3 ABIs. + (__dl_runtime_resolve): Cast the symtab initializer to the + right type. + (RTLD_START): Use it. Adjust it for all 3 ABIs. + (elf_machine_rel): Mark as always_inline in RTLD_BOOTSTRAP. + Handle 64-bit R_MIPS_REL composite relocation and accept + R_MIPS_64 relocations to shift addend size to 64 bits. + Document assumption regarding local GOT entries. Document + backward-compatibility departing from the ABI behavior in + applying relocations that reference section symbols, no longer + used. Support relocations to mis-aligned offsets. + * sysdeps/mips/mips64/dl-machine.h: Deleted, obsolete. + * sysdeps/unix/sysv/linux/mips/readelflib.c: New file. * sysdeps/unix/sysv/linux/mips/kernel_sigaction.h diff --git a/sysdeps/mips/dl-machine.h b/sysdeps/mips/dl-machine.h index c4864c21d2..62c3f20736 100644 --- a/sysdeps/mips/dl-machine.h +++ b/sysdeps/mips/dl-machine.h @@ -32,6 +32,8 @@ #error ENTRY_POINT needs to be defined for MIPS. #endif +#include <sys/asm.h> + /* The offset of gp from GOT might be system-dependent. It's set by ld. The same value is also */ #define OFFSET_GP_GOT 0x7ff0 @@ -72,6 +74,13 @@ do { if ((l)->l_info[DT_MIPS (RLD_MAP)]) \ static inline int __attribute_used__ elf_machine_matches_host (const ElfW(Ehdr) *ehdr) { +#if _MIPS_SIM == _MIPS_SIM_ABI32 || _MIPS_SIM == _MIPS_SIM_NABI32 + /* Don't link o32 and n32 together. */ + if (((ehdr->e_flags & EF_MIPS_ABI2) != 0) + != (_MIPS_SIM != _MIPS_SIM_ABI32)) + return 0; +#endif + switch (ehdr->e_machine) { case EM_MIPS: @@ -91,7 +100,7 @@ elf_mips_got_from_gpreg (ElfW(Addr) gpreg) /* 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. */ + uses global data. We assume its $gp points to the primary GOT. */ static inline ElfW(Addr) elf_machine_dynamic (void) { @@ -99,6 +108,9 @@ elf_machine_dynamic (void) return *elf_mips_got_from_gpreg (gp); } +#define STRINGXP(X) __STRING(X) +#define STRINGXV(X) STRINGV_(X) +#define STRINGV_(...) # __VA_ARGS__ /* Return the run-time load address of the shared object. */ static inline ElfW(Addr) @@ -106,10 +118,10 @@ elf_machine_load_address (void) { ElfW(Addr) addr; asm (" .set noreorder\n" - " la %0, here\n" - " bltzal $0, here\n" + " " STRINGXP (PTR_LA) " %0, 0f\n" + " bltzal $0, 0f\n" " nop\n" - "here: subu %0, $31, %0\n" + "0: " STRINGXP (PTR_SUBU) " %0, $31, %0\n" " .set reorder\n" : "=r" (addr) : /* No inputs */ @@ -242,6 +254,55 @@ elf_machine_runtime_link_map (ElfW(Addr) gpreg, ElfW(Addr) stub_pc) return NULL; } +#if _MIPS_SIM == _MIPS_SIM_ABI32 +#define ELF_DL_FRAME_SIZE 40 + +#define ELF_DL_SAVE_ARG_REGS "\ + sw $15, 36($29)\n \ + sw $4, 16($29)\n \ + sw $5, 20($29)\n \ + sw $6, 24($29)\n \ + sw $7, 28($29)\n \ +" + +#define ELF_DL_RESTORE_ARG_REGS "\ + lw $31, 36($29)\n \ + lw $4, 16($29)\n \ + lw $5, 20($29)\n \ + lw $6, 24($29)\n \ + lw $7, 28($29)\n \ +" + +#define IFABIO32(X) X + +#else /* _MIPS_SIM == _MIPS_SIM_NABI32 || _MIPS_SIM == _MIPS_SIM_ABI64 */ + +#define ELF_DL_FRAME_SIZE 64 + +#define ELF_DL_SAVE_ARG_REGS "\ + sd $15, 56($29)\n \ + sd $4, 8($29)\n \ + sd $5, 16($29)\n \ + sd $6, 24($29)\n \ + sd $7, 32($29)\n \ + sd $8, 40($29)\n \ + sd $9, 48($29)\n \ +" + +#define ELF_DL_RESTORE_ARG_REGS "\ + ld $31, 56($29)\n \ + ld $4, 8($29)\n \ + ld $5, 16($29)\n \ + ld $6, 24($29)\n \ + ld $7, 32($29)\n \ + ld $8, 40($29)\n \ + ld $9, 48($29)\n \ +" + +#define IFABIO32(X) + +#endif + /* Define mips specific runtime resolver. The function __dl_runtime_resolve is called from assembler function _dl_runtime_resolve which converts special argument registers t7 ($15) and t8 ($24): @@ -272,9 +333,8 @@ __dl_runtime_resolve (ElfW(Word) sym_index, \ { \ struct link_map *l = elf_machine_runtime_link_map (old_gpreg, stub_pc); \ const ElfW(Sym) *const symtab \ - = (const void *) D_PTR (l, l_info[DT_SYMTAB]); \ - const char *strtab \ - = (const void *) D_PTR (l, l_info[DT_STRTAB]); \ + = (const ElfW(Sym) *) D_PTR (l, l_info[DT_SYMTAB]); \ + const char *strtab = (const void *) D_PTR (l, l_info[DT_STRTAB]); \ ElfW(Addr) *got \ = (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]); \ const ElfW(Word) local_gotno \ @@ -333,36 +393,30 @@ asm ("\n \ .type _dl_runtime_resolve,@function\n \ .ent _dl_runtime_resolve\n \ _dl_runtime_resolve:\n \ - .frame $29, 40, $31\n \ + .frame $29, " STRINGXP(ELF_DL_FRAME_SIZE) ", $31\n \ .set noreorder\n \ # Save GP.\n \ move $3, $28\n \ + # Save arguments and sp value in stack.\n \ + " STRINGXP(PTR_SUBIU) " $29, " STRINGXP(ELF_DL_FRAME_SIZE) "\n \ # Modify t9 ($25) so as to point .cpload instruction.\n \ - addu $25, 8\n \ + " IFABIO32(STRINGXP(PTR_ADDIU) " $25, 12\n") " \ # Compute GP.\n \ - .cpload $25\n \ + " STRINGXP(SETUP_GP) "\n \ + " STRINGXV(SETUP_GP64 (0, _dl_runtime_resolve)) "\n \ .set reorder\n \ # Save slot call pc.\n \ move $2, $31\n \ - # Save arguments and sp value in stack.\n \ - subu $29, 40\n \ - .cprestore 32\n \ - sw $15, 36($29)\n \ - sw $4, 16($29)\n \ - sw $5, 20($29)\n \ - sw $6, 24($29)\n \ - sw $7, 28($29)\n \ + " IFABIO32(STRINGXP(CPRESTORE(32))) "\n \ + " ELF_DL_SAVE_ARG_REGS " \ move $4, $24\n \ move $5, $15\n \ move $6, $3\n \ move $7, $2\n \ jal __dl_runtime_resolve\n \ - lw $31, 36($29)\n \ - lw $4, 16($29)\n \ - lw $5, 20($29)\n \ - lw $6, 24($29)\n \ - lw $7, 28($29)\n \ - addu $29, 40\n \ + " ELF_DL_RESTORE_ARG_REGS " \ + " STRINGXP(RESTORE_GP64) "\n \ + " STRINGXP(PTR_ADDIU) " $29, " STRINGXP(ELF_DL_FRAME_SIZE) "\n \ move $25, $2\n \ jr $25\n \ .end _dl_runtime_resolve\n \ @@ -374,7 +428,6 @@ _dl_runtime_resolve:\n \ #define ELF_MACHINE_USER_ADDRESS_MASK 0x80000000UL - /* 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. @@ -392,71 +445,71 @@ _dl_runtime_resolve:\n \ #define RTLD_START asm (\ ".text\n"\ - _RTLD_PROLOGUE(ENTRY_POINT)\ - ".set noreorder\n\ - bltzal $0, 0f\n\ - nop\n\ -0: .cpload $31\n\ - .set reorder\n\ + _RTLD_PROLOGUE(ENTRY_POINT) "\ + " STRINGXV(SETUP_GPX($25)) "\n\ + " STRINGXV(SETUP_GPX64($18,$25)) "\n\ # i386 ABI book says that the first entry of GOT holds\n\ # the address of the dynamic structure. Though MIPS ABI\n\ # doesn't say nothing about this, I emulate this here.\n\ - la $4, _DYNAMIC\n\ + " STRINGXP(PTR_LA) " $4, _DYNAMIC\n\ # Subtract OFFSET_GP_GOT\n\ - sw $4, -0x7ff0($28)\n\ + " STRINGXP(PTR_S) " $4, -0x7ff0($28)\n\ move $4, $29\n\ - subu $29, 16\n\ + " STRINGXP(PTR_SUBIU) " $29, 16\n\ \n\ - la $8, coff\n\ - bltzal $8, coff\n\ -coff: subu $8, $31, $8\n\ + " STRINGXP(PTR_LA) " $8, .Lcoff\n\ + bltzal $8, .Lcoff\n\ +.Lcoff: " STRINGXP(PTR_SUBU) " $8, $31, $8\n\ \n\ - la $25, _dl_start\n\ - addu $25, $8\n\ + " STRINGXP(PTR_LA) " $25, _dl_start\n\ + " STRINGXP(PTR_ADDU) " $25, $8\n\ jalr $25\n\ \n\ - addiu $29, 16\n\ + " STRINGXP(PTR_ADDIU) " $29, 16\n\ # Get the value of label '_dl_start_user' in t9 ($25).\n\ - la $25, _dl_start_user\n\ + " STRINGXP(PTR_LA) " $25, _dl_start_user\n\ .globl _dl_start_user\n\ + .type _dl_start_user,@function\n\ + .ent _dl_start_user\n\ _dl_start_user:\n\ - .set noreorder\n\ - .cpload $25\n\ - .set reorder\n\ + " STRINGXP(SETUP_GP) "\n\ + " STRINGXV(SETUP_GP64($18,_dl_start_user)) "\n\ move $16, $28\n\ # Save the user entry point address in a saved register.\n\ move $17, $2\n\ # Store the highest stack address\n\ - sw $29, __libc_stack_end\n\ + " STRINGXP(PTR_S) " $29, __libc_stack_end\n\ # See if we were run as a command with the executable file\n\ # name as an extra leading argument.\n\ lw $2, _dl_skip_args\n\ beq $2, $0, 1f\n\ # Load the original argument count.\n\ - lw $4, 0($29)\n\ + " STRINGXP(PTR_L) " $4, 0($29)\n\ # Subtract _dl_skip_args from it.\n\ subu $4, $2\n\ # Adjust the stack pointer to skip _dl_skip_args words.\n\ - sll $2, 2\n\ - addu $29, $2\n\ + sll $2, " STRINGXP (PTRLOG) "\n\ + " STRINGXP(PTR_ADDU) " $29, $2\n\ # Save back the modified argument count.\n\ - sw $4, 0($29)\n\ + " STRINGXP(PTR_S) " $4, 0($29)\n\ 1: # Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env) \n\ - lw $4, _rtld_local\n\ - lw $5, 0($29)\n\ - la $6, 4($29)\n\ - sll $7, $5, 2\n\ - addu $7, $7, $6\n\ - addu $7, $7, 4\n\ - subu $29, 16\n\ + " STRINGXP(PTR_L) " $4, _rtld_local\n\ + " STRINGXP(PTR_L) /* or lw??? fixme */ " $5, 0($29)\n\ + " STRINGXP(PTR_LA) " $6, " STRINGXP (PTRSIZE) "($29)\n\ + sll $7, $5, " STRINGXP (PTRLOG) "\n\ + " STRINGXP(PTR_ADDU) " $7, $7, $6\n\ + " STRINGXP(PTR_ADDU) " $7, $7, " STRINGXP (PTRSIZE) " \n\ + " STRINGXP(PTR_SUBIU) " $29, 32\n\ + " STRINGXP(SAVE_GP(16)) "\n\ # Call the function to run the initializers.\n\ jal _dl_init_internal\n\ - addiu $29, 16\n\ + " STRINGXP(PTR_ADDIU) " $29, 32\n\ # Pass our finalizer function to the user in $2 as per ELF ABI.\n\ - la $2, _dl_fini\n\ + " STRINGXP(PTR_LA) " $2, _dl_fini\n\ # Jump to the user entry point.\n\ move $25, $17\n\ - jr $25\n\t"\ + jr $25\n\ + .end _dl_start_user\n\t"\ _RTLD_EPILOGUE(ENTRY_POINT)\ ".previous"\ ); @@ -472,6 +525,9 @@ _dl_start_user:\n\ MAP is the object containing the reloc. */ static inline void +#ifdef RTLD_BOOTSTRAP + __attribute__ ((always_inline)) +#endif elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc, const ElfW(Sym) *sym, const struct r_found_version *version, ElfW(Addr) *const reloc_addr) @@ -490,9 +546,19 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc, switch (r_type) { +#if _MIPS_SIM == _MIPS_SIM_ABI64 + case (R_MIPS_64 << 8) | R_MIPS_REL32: +#else case R_MIPS_REL32: +#endif { int symidx = ELFW(R_SYM) (reloc->r_info); + ElfW(Addr) reloc_value; + + /* Support relocations on mis-aligned offsets. Should we ever + implement RELA, this should be replaced with an assignment + from reloc->r_addend. */ + __builtin_memcpy (&reloc_value, reloc_addr, sizeof (reloc_value)); if (symidx) { @@ -501,10 +567,25 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc, if (symidx < gotsym) { + /* This wouldn't work for a symbol imported from other + libraries for which there's no GOT entry, but MIPS + requires every symbol referenced in a dynamic + relocation to have a GOT entry in the primary GOT, + so we only get here for locally-defined symbols. + For section symbols, we should *NOT* be adding + sym->st_value (per the definition of the meaning of + S in reloc expressions in the ELF64 MIPS ABI), + since it should have already been added to + reloc_value by the linker, but older versions of + GNU ld didn't add it, and newer versions don't emit + useless relocations to section symbols any more, so + it is safe to keep on adding sym->st_value, even + though it's not ABI compliant. Some day we should + bite the bullet and stop doing this. */ #ifndef RTLD_BOOTSTRAP if (map != &GL(dl_rtld_map)) #endif - *reloc_addr += sym->st_value + map->l_addr; + reloc_value += sym->st_value + map->l_addr; } else { @@ -515,7 +596,7 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc, = (const ElfW(Word)) map->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val; - *reloc_addr += got[symidx + local_gotno - gotsym]; + reloc_value += got[symidx + local_gotno - gotsym]; #endif } } @@ -523,11 +604,27 @@ elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc, #ifndef RTLD_BOOTSTRAP if (map != &GL(dl_rtld_map)) #endif - *reloc_addr += map->l_addr; + reloc_value += map->l_addr; + + __builtin_memcpy (reloc_addr, &reloc_value, sizeof (reloc_value)); } break; case R_MIPS_NONE: /* Alright, Wilbur. */ break; +#if _MIPS_SIM == _MIPS_SIM_ABI64 + case R_MIPS_64: + /* For full compliance with the ELF64 ABI, one must precede the + _REL32/_64 pair of relocations with a _64 relocation, such + that the in-place addend is read as a 64-bit value. IRIX + didn't pick up on this requirement, so we treat the + _REL32/_64 relocation as a 64-bit relocation even if it's by + itself. For ABI compliance, we ignore such _64 dummy + relocations. For RELA, this may be simply removed, since + it's totally unnecessary. */ + if (ELFW(R_SYM) (reloc->r_info) == 0) + break; + /* Fall through. */ +#endif default: _dl_reloc_bad_type (map, r_type, 0); break; diff --git a/sysdeps/mips/mips64/dl-machine.h b/sysdeps/mips/mips64/dl-machine.h deleted file mode 100644 index 64731b863a..0000000000 --- a/sysdeps/mips/mips64/dl-machine.h +++ /dev/null @@ -1,594 +0,0 @@ -/* Machine-dependent ELF dynamic relocation inline functions. MIPS64 version. - Copyright (C) 1996,1997,1999,2000,2001,2002 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Kazumoto Kojima <kkojima@info.kanagawa-u.ac.jp>. - - 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, 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 "MIPS" - -#define ELF_MACHINE_NO_PLT - -#include <entry.h> - -#ifndef ENTRY_POINT -#error ENTRY_POINT needs to be defined for MIPS. -#endif - -#ifndef _RTLD_PROLOGUE -# define _RTLD_PROLOGUE(entry) "\n\t.globl " __STRING(entry) \ - "\n\t.ent " __STRING(entry) \ - "\n\t" __STRING(entry) ":\n\t" -#endif - -#ifndef _RTLD_EPILOGUE -# define _RTLD_EPILOGUE(entry) "\t.end " __STRING(entry) "\n" -#endif - -/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. - This makes no sense on MIPS but we have to define this to R_MIPS_REL32 - to avoid the asserts in dl-lookup.c from blowing. */ -#define ELF_MACHINE_JMP_SLOT R_MIPS_REL32 -#define elf_machine_type_class(type) ELF_RTYPE_CLASS_PLT - -/* Translate a processor specific dynamic tag to the index - in l_info array. */ -#define DT_MIPS(x) (DT_MIPS_##x - DT_LOPROC + DT_NUM) - -#if 0 -/* We may need 64k alignment. */ -#define ELF_MACHINE_ALIGN_MASK 0xffff -#endif - -/* - * MIPS libraries are usually linked to a non-zero base address. We - * subtrace the base address from the address where we map the object - * to. This results in more efficient address space usage. - */ -#if 0 -#define MAP_BASE_ADDR(l) ((l)->l_info[DT_MIPS(BASE_ADDRESS)] ? \ - (l)->l_info[DT_MIPS(BASE_ADDRESS)]->d_un.d_ptr : 0) -#else -#define MAP_BASE_ADDR(l) 0x5ffe0000 -#endif - -/* If there is a DT_MIPS_RLD_MAP entry in the dynamic section, fill it in - with the run-time address of the r_debug structure */ -#define ELF_MACHINE_DEBUG_SETUP(l,r) \ -do { if ((l)->l_info[DT_MIPS (RLD_MAP)]) \ - *(ElfW(Addr) *)((l)->l_info[DT_MIPS (RLD_MAP)]->d_un.d_ptr) = \ - (ElfW(Addr)) (r); \ - } while (0) - -/* Return nonzero iff ELF header is compatible with the running host. */ -static inline int __attribute__ ((unused)) -elf_machine_matches_host (const ElfW(Ehdr) *ehdr) -{ - switch (ehdr->e_machine) - { - case EM_MIPS: - case EM_MIPS_RS3_LE: - return 1; - default: - return 0; - } -} - -static inline ElfW(Addr) * -elf_mips_got_from_gpreg (ElfW(Addr) gpreg) -{ - /* FIXME: the offset of gp from GOT may be system-dependent. */ - return (ElfW(Addr) *) (gpreg - 0x7ff0); -} - -/* 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 ElfW(Addr) -elf_machine_dynamic (void) -{ - register ElfW(Addr) gp __asm__ ("$28"); - - return *elf_mips_got_from_gpreg (gp); -} - - -/* Return the run-time load address of the shared object. */ -static inline ElfW(Addr) -elf_machine_load_address (void) -{ - ElfW(Addr) addr; - asm (" .set noreorder\n" - " dla %0, here\n" - " bltzal $0, here\n" - " nop\n" - "here: dsubu %0, $31, %0\n" - " .set reorder\n" - : "=r" (addr) - : /* No inputs */ - : "$31"); - return addr; -} - -/* The MSB of got[1] of a gnu object is set to identify gnu objects. */ -#define ELF_MIPS_GNU_GOT1_MASK 0x80000000 - -/* Relocate GOT. */ -static inline void -elf_machine_got_rel (struct link_map *map, int lazy) -{ - ElfW(Addr) *got; - ElfW(Sym) *sym; - int i, n; - const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]); - -#define RESOLVE_GOTSYM(sym) \ - ({ \ - const ElfW(Sym) *ref = sym; \ - ElfW(Addr) sym_loadaddr; \ - sym_loadaddr = _dl_lookup_symbol (strtab + sym->st_name, &ref, \ - map->l_scope, \ - map->l_name, R_MIPS_REL32);\ - (ref)? sym_loadaddr + ref->st_value: 0; \ - }) - - got = (ElfW(Addr) *) D_PTR (map, l_info[DT_PLTGOT]); - - /* got[0] is reserved. got[1] is also reserved for the dynamic object - generated by gnu ld. Skip these reserved entries from relocation. */ - i = (got[1] & ELF_MIPS_GNU_GOT1_MASK)? 2: 1; - n = map->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val; - /* Add the run-time display to all local got entries. */ - while (i < n) - got[i++] += map->l_addr; - - /* Handle global got entries. */ - got += n; - sym = (ElfW(Sym) *) D_PTR (map, l_info[DT_SYMTAB]); - sym += map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val; - i = (map->l_info[DT_MIPS (SYMTABNO)]->d_un.d_val - - map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val); - - while (i--) - { - if (sym->st_shndx == SHN_UNDEF) - { - if (ELFW(ST_TYPE) (sym->st_info) == STT_FUNC) - { - if (sym->st_value && lazy) - *got = sym->st_value + map->l_addr; - else - *got = RESOLVE_GOTSYM (sym); - } - else /* if (*got == 0 || *got == QS) */ - *got = RESOLVE_GOTSYM (sym); - } - else if (sym->st_shndx == SHN_COMMON) - *got = RESOLVE_GOTSYM (sym); - else if (ELFW(ST_TYPE) (sym->st_info) == STT_FUNC - && *got != sym->st_value - && lazy) - *got += map->l_addr; - else if (ELFW(ST_TYPE) (sym->st_info) == STT_SECTION) - { - if (sym->st_other == 0) - *got += map->l_addr; - } - else - *got = RESOLVE_GOTSYM (sym); - - got++; - sym++; - } - -#undef RESOLVE_GOTSYM - - return; -} - -/* Set up the loaded object described by L so its stub function - will jump to the on-demand fixup code in dl-runtime.c. */ - -static inline int -elf_machine_runtime_setup (struct link_map *l, int lazy, int profile) -{ - ElfW(Addr) *got; - extern void _dl_runtime_resolve (ElfW(Word)); - extern int _dl_mips_gnu_objects; - -#ifdef RTLD_BOOTSTRAP - { - return lazy; - } -#endif - if (lazy) - { - /* The GOT entries for functions have not yet been filled in. - Their initial contents will arrange when called to put an - offset into the .dynsym section in t8, the return address - in t7 and then jump to _GLOBAL_OFFSET_TABLE[0]. */ - got = (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]); - - /* This function will get called to fix up the GOT entry indicated by - the register t8, and then jump to the resolved address. */ - got[0] = (ElfW(Addr)) &_dl_runtime_resolve; - - /* Store l to _GLOBAL_OFFSET_TABLE[1] for gnu object. The MSB - of got[1] of a gnu object is set to identify gnu objects. - Where we can store l for non gnu objects? XXX */ - if ((got[1] & ELF_MIPS_GNU_GOT1_MASK) != 0) - got[1] = (ElfW(Addr)) ((unsigned) l | ELF_MIPS_GNU_GOT1_MASK); - else - _dl_mips_gnu_objects = 0; - } - - /* Relocate global offset table. */ - elf_machine_got_rel (l, lazy); - - return lazy; -} - -/* Get link_map for this object. */ -static inline struct link_map * -elf_machine_runtime_link_map (ElfW(Addr) gpreg, ElfW(Addr) stub_pc) -{ - extern int _dl_mips_gnu_objects; - - /* got[1] is reserved to keep its link map address for the shared - object generated by the gnu linker. If all are such objects, we - can find the link map from current GPREG simply. If not so, get - the link map for caller's object containing STUB_PC. */ - - if (_dl_mips_gnu_objects) - { - ElfW(Addr) *got = elf_mips_got_from_gpreg (gpreg); - ElfW(Word) g1; - - g1 = ((ElfW(Word) *) got)[1]; - - if ((g1 & ELF_MIPS_GNU_GOT1_MASK) != 0) - { - struct link_map *l = - (struct link_map *) (g1 & ~ELF_MIPS_GNU_GOT1_MASK); - ElfW(Addr) base, limit; - const ElfW(Phdr) *p = l->l_phdr; - ElfW(Half) this, nent = l->l_phnum; - - /* For the common case of a stub being called from the containing - object, STUB_PC will point to somewhere within the object that - is described by the link map fetched via got[1]. Otherwise we - have to scan all maps. */ - for (this = 0; this < nent; this++) - { - if (p[this].p_type == PT_LOAD) - { - base = p[this].p_vaddr + l->l_addr; - limit = base + p[this].p_memsz; - if (stub_pc >= base && stub_pc < limit) - return l; - } - this++; - } - } - } - - { - struct link_map *l = GL(dl_loaded); - - while (l) - { - ElfW(Addr) base, limit; - const ElfW(Phdr) *p = l->l_phdr; - ElfW(Half) this, nent = l->l_phnum; - - for (this = 0; this < nent; this++) - { - if (p[this].p_type == PT_LOAD) - { - base = p[this].p_vaddr + l->l_addr; - limit = base + p[this].p_memsz; - if (stub_pc >= base && stub_pc < limit) - return l; - } - } - l = l->l_next; - } - } - - _dl_signal_error (0, NULL, NULL, "cannot find runtime link map"); - return NULL; -} - -/* Mips has no PLT but define elf_machine_relplt to be elf_machine_rel. */ -#define elf_machine_relplt elf_machine_rel - -/* Define mips specific runtime resolver. The function __dl_runtime_resolve - is called from assembler function _dl_runtime_resolve which converts - special argument registers t7 ($15) and t8 ($24): - t7 address to return to the caller of the function - t8 index for this function symbol in .dynsym - to usual c arguments. */ - -#define ELF_MACHINE_RUNTIME_TRAMPOLINE \ -/* The flag _dl_mips_gnu_objects is set if all dynamic objects are \ - generated by the gnu linker. */ \ -int _dl_mips_gnu_objects = 1; \ - \ -/* This is called from assembly stubs below which the compiler can't see. */ \ -static ElfW(Addr) \ -__dl_runtime_resolve (ElfW(Word), ElfW(Word), ElfW(Addr), ElfW(Addr)) \ - __attribute__ ((unused)); \ - \ -static ElfW(Addr) \ -__dl_runtime_resolve (ElfW(Word) sym_index, \ - ElfW(Word) return_address, \ - ElfW(Addr) old_gpreg, \ - ElfW(Addr) stub_pc) \ -{ \ - struct link_map *l = elf_machine_runtime_link_map (old_gpreg, stub_pc); \ - const ElfW(Sym) *const symtab \ - = (const ElfW(Sym) *) D_PTR (l, l_info[DT_SYMTAB]); \ - const char *strtab = (const void *) D_PTR (l, l_info[DT_STRTAB]); \ - const ElfW(Addr) *got \ - = (const ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]); \ - const ElfW(Word) local_gotno \ - = (const ElfW(Word)) l->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val; \ - const ElfW(Word) gotsym \ - = (const ElfW(Word)) l->l_info[DT_MIPS (GOTSYM)]->d_un.d_val; \ - const ElfW(Sym) *definer; \ - ElfW(Addr) loadbase; \ - ElfW(Addr) funcaddr; \ - \ - /* Look up the symbol's run-time value. */ \ - definer = &symtab[sym_index]; \ - \ - loadbase = _dl_lookup_symbol (strtab + definer->st_name, &definer, \ - l->l_scope, l->l_name, \ - R_MIPS_REL32); \ - \ - /* Apply the relocation with that value. */ \ - funcaddr = loadbase + definer->st_value; \ - *(got + local_gotno + sym_index - gotsym) = funcaddr; \ - \ - return funcaddr; \ -} \ - \ -asm ("\n \ - .text\n \ - .align 3\n \ - .globl _dl_runtime_resolve\n \ - .type _dl_runtime_resolve,@function\n \ - .ent _dl_runtime_resolve\n \ -_dl_runtime_resolve:\n \ - .set noreorder\n \ - # Save old GP to $3.\n \ - move $3,$28\n \ - # Modify t9 ($25) so as to point .cpload instruction.\n \ - daddu $25,2*8\n \ - # Compute GP.\n \ - .cpload $25\n \ - .set reorder\n \ - # Save slot call pc.\n \ - move $2, $31\n \ - # Save arguments and sp value in stack.\n \ - dsubu $29, 10*8\n \ - .cprestore 8*8\n \ - sd $15, 9*8($29)\n \ - sd $4, 3*8($29)\n \ - sd $5, 4*8($29)\n \ - sd $6, 5*8($29)\n \ - sd $7, 6*8($29)\n \ - sd $16, 7*8($29)\n \ - move $16, $29\n \ - move $4, $24\n \ - move $5, $15\n \ - move $6, $3\n \ - move $7, $2\n \ - jal __dl_runtime_resolve\n \ - move $29, $16\n \ - ld $31, 9*8($29)\n \ - ld $4, 3*8($29)\n \ - ld $5, 4*8($29)\n \ - ld $6, 5*8($29)\n \ - ld $7, 6*8($29)\n \ - ld $16, 7*8($29)\n \ - daddu $29, 10*8\n \ - move $25, $2\n \ - jr $25\n \ - .end _dl_runtime_resolve\n \ - .previous\n \ -"); - -/* Mask identifying addresses reserved for the user program, - where the dynamic linker should not map anything. */ -#define ELF_MACHINE_USER_ADDRESS_MASK 0x80000000UL - - - -/* 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. - Note how we have to be careful about two things: - - 1) That we allocate a minimal stack of 24 bytes for - every function call, the MIPS ABI states that even - if all arguments are passed in registers the procedure - called can use the 16 byte area pointed to by $sp - when it is called to store away the arguments passed - to it. - - 2) That under Linux the entry is named __start - and not just plain _start. */ - -#define RTLD_START asm ("\ - .text\n\ - .align 3\n"\ -_RTLD_PROLOGUE (ENTRY_POINT)\ -" .globl _dl_start_user\n\ - .set noreorder\n\ - bltzal $0, 0f\n\ - nop\n\ -0: .cpload $31\n\ - .set reorder\n\ - # i386 ABI book says that the first entry of GOT holds\n\ - # the address of the dynamic structure. Though MIPS ABI\n\ - # doesn't say nothing about this, I emulate this here.\n\ - dla $4, _DYNAMIC\n\ - sd $4, -0x7ff0($28)\n\ - dsubu $29, 16\n\ - move $4, $29\n\ - jal _dl_start\n\ - daddiu $29, 16\n\ - # Get the value of label '_dl_start_user' in t9 ($25).\n\ - dla $25, _dl_start_user\n\ -_dl_start_user:\n\ - .set noreorder\n\ - .cpload $25\n\ - .set reorder\n\ - move $16, $28\n\ - # Save the user entry point address in saved register.\n\ - move $17, $2\n\ - # Store the highest stack address\n\ - sd $29, __libc_stack_end\n\ - # See if we were run as a command with the executable file\n\ - # name as an extra leading argument.\n\ - ld $2, _dl_skip_args\n\ - beq $2, $0, 1f\n\ - # Load the original argument count.\n\ - ld $4, 0($29)\n\ - # Subtract _dl_skip_args from it.\n\ - dsubu $4, $2\n\ - # Adjust the stack pointer to skip _dl_skip_args words.\n\ - dsll $2,2\n\ - daddu $29, $2\n\ - # Save back the modified argument count.\n\ - sd $4, 0($29)\n\ -1: # Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env) \n\ - ld $4, _rtld_local\n\ - ld $5, 0($29)\n\ - dla $6, 4($29)\n\ - dla $7, 8($29)\n\ - dsubu $29, 16\n\ - # Call the function to run the initializers.\n\ - jal _dl_init_internal\n\ - daddiu $29, 16\n\ - # Pass our finalizer function to the user in ra.\n\ - dla $31, _dl_fini\n\ - # Jump to the user entry point.\n\ -1: # Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env) \n\ - lw $4, _rtld_local\n\ - lw $5, 0($29)\n\ - la $6, 4($29)\n\ - la $7, 8($29)\n\ - subu $29, 16\n\ - # Call the function to run the initializers.\n\ - jal _dl_init_internal\n\ - addiu $29, 16\n\ - # Pass our finalizer function to the user in ra.\n\ - dla $31, _dl_fini\n\ - # Jump to the user entry point.\n\ - move $25, $17\n\ - ld $4, 0($29)\n\ - ld $5, 1*8($29)\n\ - ld $6, 2*8$29)\n\ - ld $7, 3*8($29)\n\ - jr $25\n"\ -_RTLD_EPILOGUE(ENTRY_POINT) \ - "\n.previous"\ -); - - -/* The MIPS never uses Elfxx_Rela relocations. */ -#define ELF_MACHINE_NO_RELA 1 - -#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_rel (struct link_map *map, const ElfW(Rel) *reloc, - const ElfW(Sym) *sym, const struct r_found_version *version, - ElfW(Addr) *const reloc_addr) -{ - const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info); - ElfW(Addr) loadbase; - ElfW(Addr) undo __attribute__ ((unused)); - - switch (r_type) - { - case R_MIPS_REL32: - { - ElfW(Addr) undo = 0; - - if (ELFW(ST_BIND) (sym->st_info) == STB_LOCAL - && (ELFW(ST_TYPE) (sym->st_info) == STT_SECTION - || ELFW(ST_TYPE) (sym->st_info) == STT_NOTYPE)) - { - *reloc_addr += map->l_addr; - break; - } -#ifndef RTLD_BOOTSTRAP - /* This is defined in rtld.c, but nowhere in the static libc.a; - make the reference weak so static programs can still link. This - declaration cannot be done when compiling rtld.c (i.e. #ifdef - RTLD_BOOTSTRAP) because rtld.c contains the common defn for - _dl_rtld_map, which is incompatible with a weak decl in the same - file. */ -# ifndef SHARED - weak_extern (GL(dl_rtld_map)); -# endif - if (map == &GL(dl_rtld_map)) - /* Undo the relocation done here during bootstrapping. Now we will - relocate it anew, possibly using a binding found in the user - program or a loaded library rather than the dynamic linker's - built-in definitions used while loading those libraries. */ - undo = map->l_addr + sym->st_value; -#endif - loadbase = RESOLVE (&sym, version, 0); - *reloc_addr += (sym ? (loadbase + sym->st_value) : 0) - undo; - } - break; -#ifndef RTLD_BOOTSTRAP - case R_MIPS_NONE: /* Alright, Wilbur. */ - break; -#endif - default: - _dl_reloc_bad_type (map, r_type, 0); - break; - } -} - -static inline void -elf_machine_rel_relative (ElfW(Addr) l_addr, const ElfW(Rel) *reloc, - ElfW(Addr) *const reloc_addr) -{ - /* XXX Nothing to do. There is no relative relocation, right? */ -} - -static inline void -elf_machine_lazy_rel (struct link_map *map, ElfW(Addr) l_addr, - const ElfW(Rel) *reloc) -{ - /* Do nothing. */ -} - -#endif /* RESOLVE */ |