generic-library/bionic
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[MIPS64] Dynamic linker

Browse Source 
Change-Id: I937c7c776cae3d66e214798d5217a922cd106bfc
Signed-off-by: Chris Dearman <chris.dearman@imgtec.com>
Signed-off-by: Duane Sand <duane.sand@imgtec.com>
This commit is contained in:
Chris Dearman
2014-02-06 20:36:51 -08:00
committed by Elliott Hughes
parent c856baeead
commit 9918665a45
5 changed files with 200 additions and 47 deletions
Download Patch File Download Diff File Expand all files Collapse all files

89
linker/linker.cpp
View File

@@ -858,7 +858,7 @@ int do_dlclose(soinfo* si) {
}
#if defined(USE_RELA)
static int soinfo_relocate_a(soinfo* si, ElfW(Rela)* rela, unsigned count, soinfo* needed[]) {
static int soinfo_relocate(soinfo* si, ElfW(Rela)* rela, unsigned count, soinfo* needed[]) {
ElfW(Sym)* symtab = si->symtab;
const char* strtab = si->strtab;
ElfW(Sym)* s;
@@ -1155,7 +1155,9 @@ static int soinfo_relocate_a(soinfo* si, ElfW(Rela)* rela, unsigned count, soinf
}
return 0;
}
#else
#else // REL, not RELA.
static int soinfo_relocate(soinfo* si, ElfW(Rel)* rel, unsigned count, soinfo* needed[]) {
ElfW(Sym)* symtab = si->symtab;
const char* strtab = si->strtab;
@@ -1337,10 +1339,21 @@ static int soinfo_relocate(soinfo* si, ElfW(Rel)* rel, unsigned count, soinfo* n
break;
#elif defined(__mips__)
case R_MIPS_REL32:
#if defined(__LP64__)
// MIPS Elf64_Rel entries contain compound relocations
// We only handle the R_MIPS_NONE|R_MIPS_64|R_MIPS_REL32 case
if (ELF64_R_TYPE2(rel->r_info) != R_MIPS_64 ||
ELF64_R_TYPE3(rel->r_info) != R_MIPS_NONE) {
DL_ERR("Unexpected compound relocation type:%d type2:%d type3:%d @ %p (%d)",
type, (unsigned)ELF64_R_TYPE2(rel->r_info),
(unsigned)ELF64_R_TYPE3(rel->r_info), rel, (int) (rel - start));
return -1;
}
#endif
count_relocation(kRelocAbsolute);
MARK(rel->r_offset);
TRACE_TYPE(RELO, "RELO REL32 %08x <- %08x %s",
reloc, sym_addr, (sym_name) ? sym_name : "*SECTIONHDR*");
TRACE_TYPE(RELO, "RELO REL32 %08zx <- %08zx %s", static_cast<size_t>(reloc),
static_cast<size_t>(sym_addr), sym_name ? sym_name : "*SECTIONHDR*");
if (s) {
*reinterpret_cast<ElfW(Addr)*>(reloc) += sym_addr;
} else {
@@ -1376,7 +1389,7 @@ static int soinfo_relocate(soinfo* si, ElfW(Rel)* rel, unsigned count, soinfo* n
#if defined(__mips__)
static bool mips_relocate_got(soinfo* si, soinfo* needed[]) {
unsigned* got = si->plt_got;
ElfW(Addr)** got = si->plt_got;
if (got == NULL) {
return true;
}
@@ -1385,55 +1398,43 @@ static bool mips_relocate_got(soinfo* si, soinfo* needed[]) {
unsigned symtabno = si->mips_symtabno;
ElfW(Sym)* symtab = si->symtab;
/*
* got[0] is address of lazy resolver function
* got[1] may be used for a GNU extension
* set it to a recognizable address in case someone calls it
* (should be _rtld_bind_start)
* FIXME: maybe this should be in a separate routine
*/
// got[0] is the address of the lazy resolver function.
// got[1] may be used for a GNU extension.
// Set it to a recognizable address in case someone calls it (should be _rtld_bind_start).
// FIXME: maybe this should be in a separate routine?
if ((si->flags & FLAG_LINKER) == 0) {
size_t g = 0;
got[g++] = 0xdeadbeef;
if (got[g] & 0x80000000) {
got[g++] = 0xdeadfeed;
got[g++] = reinterpret_cast<ElfW(Addr)*>(0xdeadbeef);
if (reinterpret_cast<intptr_t>(got[g]) < 0) {
got[g++] = reinterpret_cast<ElfW(Addr)*>(0xdeadfeed);
}
/*
* Relocate the local GOT entries need to be relocated
*/
// Relocate the local GOT entries.
for (; g < local_gotno; g++) {
got[g] += si->load_bias;
got[g] = reinterpret_cast<ElfW(Addr)*>(reinterpret_cast<uintptr_t>(got[g]) + si->load_bias);
}
}
/* Now for the global GOT entries */
// Now for the global GOT entries...
ElfW(Sym)* sym = symtab + gotsym;
got = si->plt_got + local_gotno;
for (size_t g = gotsym; g < symtabno; g++, sym++, got++) {
const char* sym_name;
ElfW(Sym)* s;
// This is an undefined reference... try to locate it.
const char* sym_name = si->strtab + sym->st_name;
soinfo* lsi;
/* This is an undefined reference... try to locate it */
sym_name = si->strtab + sym->st_name;
s = soinfo_do_lookup(si, sym_name, &lsi, needed);
ElfW(Sym)* s = soinfo_do_lookup(si, sym_name, &lsi, needed);
if (s == NULL) {
/* We only allow an undefined symbol if this is a weak
reference.. */
// We only allow an undefined symbol if this is a weak reference.
s = &symtab[g];
if (ELF_ST_BIND(s->st_info) != STB_WEAK) {
DL_ERR("cannot locate \"%s\"...", sym_name);
return false;
}
*got = 0;
}
else {
/* FIXME: is this sufficient?
* For reference see NetBSD link loader
* http://cvsweb.netbsd.org/bsdweb.cgi/src/libexec/ld.elf_so/arch/mips/mips_reloc.c?rev=1.53&content-type=text/x-cvsweb-markup
*/
*got = lsi->load_bias + s->st_value;
} else {
// FIXME: is this sufficient?
// For reference see NetBSD link loader
// http://cvsweb.netbsd.org/bsdweb.cgi/src/libexec/ld.elf_so/arch/mips/mips_reloc.c?rev=1.53&content-type=text/x-cvsweb-markup
*got = reinterpret_cast<ElfW(Addr)*>(lsi->load_bias + s->st_value);
}
}
return true;
@@ -1664,19 +1665,25 @@ static bool soinfo_link_image(soinfo* si) {
si->plt_rel_count = d->d_un.d_val / sizeof(ElfW(Rel));
#endif
break;
#if !defined(__LP64__)
#if defined(__mips__)
case DT_PLTGOT:
// Used by 32-bit MIPS.
si->plt_got = (unsigned *)(base + d->d_un.d_ptr);
// Used by mips and mips64.
si->plt_got = reinterpret_cast<ElfW(Addr)**>(base + d->d_un.d_ptr);
break;
#endif
case DT_DEBUG:
// Set the DT_DEBUG entry to the address of _r_debug for GDB
// if the dynamic table is writable
// FIXME: not working currently for N64
// The flags for the LOAD and DYNAMIC program headers do not agree.
// The LOAD section containng the dynamic table has been mapped as
// read-only, but the DYNAMIC header claims it is writable.
#if !(defined(__mips__) && defined(__LP64__))
if ((dynamic_flags & PF_W) != 0) {
d->d_un.d_val = reinterpret_cast<uintptr_t>(&_r_debug);
}
break;
#endif
#if defined(USE_RELA)
case DT_RELA:
si->rela = (ElfW(Rela)*) (base + d->d_un.d_ptr);
@@ -1868,13 +1875,13 @@ static bool soinfo_link_image(soinfo* si) {
#if defined(USE_RELA)
if (si->plt_rela != NULL) {
DEBUG("[ relocating %s plt ]\n", si->name );
if (soinfo_relocate_a(si, si->plt_rela, si->plt_rela_count, needed)) {
if (soinfo_relocate(si, si->plt_rela, si->plt_rela_count, needed)) {
return false;
}
}
if (si->rela != NULL) {
DEBUG("[ relocating %s ]\n", si->name );
if (soinfo_relocate_a(si, si->rela, si->rela_count, needed)) {
if (soinfo_relocate(si, si->rela, si->rela_count, needed)) {
return false;
}
}