diff options
Diffstat (limited to 'sysdeps/x86_64')
| -rw-r--r-- | sysdeps/x86_64/Makefile | 10 | ||||
| -rw-r--r-- | sysdeps/x86_64/bits/byteswap.h | 4 | ||||
| -rw-r--r-- | sysdeps/x86_64/bits/linkmap.h | 2 | ||||
| -rw-r--r-- | sysdeps/x86_64/dl-lookupcfg.h | 28 | ||||
| -rw-r--r-- | sysdeps/x86_64/dl-machine.h | 53 | ||||
| -rw-r--r-- | sysdeps/x86_64/dl-tls.h | 4 | ||||
| -rw-r--r-- | sysdeps/x86_64/dl-tlsdesc.S | 245 | ||||
| -rw-r--r-- | sysdeps/x86_64/dl-tlsdesc.h | 64 | ||||
| -rw-r--r-- | sysdeps/x86_64/tlsdesc.c | 151 | ||||
| -rw-r--r-- | sysdeps/x86_64/tlsdesc.sym | 17 |
10 files changed, 573 insertions, 5 deletions
diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile index edbdac0e34..da82093381 100644 --- a/sysdeps/x86_64/Makefile +++ b/sysdeps/x86_64/Makefile @@ -13,3 +13,13 @@ endif ifeq ($(subdir),string) sysdep_routines += cacheinfo endif + +ifeq ($(subdir),elf) +sysdep-dl-routines += tlsdesc dl-tlsdesc +sysdep_routines += tlsdesc dl-tlsdesc +sysdep-rtld-routines += tlsdesc dl-tlsdesc +endif + +ifeq ($(subdir),csu) +gen-as-const-headers += tlsdesc.sym +endif diff --git a/sysdeps/x86_64/bits/byteswap.h b/sysdeps/x86_64/bits/byteswap.h index ec2b17889d..08b38e8523 100644 --- a/sysdeps/x86_64/bits/byteswap.h +++ b/sysdeps/x86_64/bits/byteswap.h @@ -1,5 +1,5 @@ /* Macros to swap the order of bytes in integer values. - Copyright (C) 1997, 1998, 2000, 2002, 2003, 2007 + Copyright (C) 1997, 1998, 2000, 2002, 2003, 2007, 2008 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -18,7 +18,7 @@ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ -#if !defined _BYTESWAP_H && !defined _NETINET_IN_H +#if !defined _BYTESWAP_H && !defined _NETINET_IN_H && !defined _ENDIAN_H # error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead." #endif diff --git a/sysdeps/x86_64/bits/linkmap.h b/sysdeps/x86_64/bits/linkmap.h index 8ea7157156..dd0d140874 100644 --- a/sysdeps/x86_64/bits/linkmap.h +++ b/sysdeps/x86_64/bits/linkmap.h @@ -3,6 +3,7 @@ struct link_map_machine { Elf64_Addr plt; /* Address of .plt + 0x16 */ Elf64_Addr gotplt; /* Address of .got + 0x18 */ + void *tlsdesc_table; /* Address of TLS descriptor hash table. */ }; #else @@ -10,5 +11,6 @@ struct link_map_machine { Elf32_Addr plt; /* Address of .plt + 0x16 */ Elf32_Addr gotplt; /* Address of .got + 0x0c */ + void *tlsdesc_table; /* Address of TLS descriptor hash table. */ }; #endif diff --git a/sysdeps/x86_64/dl-lookupcfg.h b/sysdeps/x86_64/dl-lookupcfg.h new file mode 100644 index 0000000000..2af2b9e8fa --- /dev/null +++ b/sysdeps/x86_64/dl-lookupcfg.h @@ -0,0 +1,28 @@ +/* Configuration of lookup functions. + Copyright (C) 2005, 2008 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#define DL_UNMAP_IS_SPECIAL + +#include_next <dl-lookupcfg.h> + +struct link_map; + +extern void internal_function _dl_unmap (struct link_map *map); + +#define DL_UNMAP(map) _dl_unmap (map) diff --git a/sysdeps/x86_64/dl-machine.h b/sysdeps/x86_64/dl-machine.h index 31a7013d50..959b1328d7 100644 --- a/sysdeps/x86_64/dl-machine.h +++ b/sysdeps/x86_64/dl-machine.h @@ -26,6 +26,7 @@ #include <sys/param.h> #include <sysdep.h> #include <tls.h> +#include <dl-tlsdesc.h> /* Return nonzero iff ELF header is compatible with the running host. */ static inline int __attribute__ ((unused)) @@ -131,6 +132,10 @@ elf_machine_runtime_setup (struct link_map *l, int lazy, int profile) got[2] = (Elf64_Addr) &_dl_runtime_resolve; } + if (l->l_info[ADDRIDX (DT_TLSDESC_GOT)] && lazy) + *(Elf64_Addr*)(D_PTR (l, l_info[ADDRIDX (DT_TLSDESC_GOT)]) + l->l_addr) + = (Elf64_Addr) &_dl_tlsdesc_resolve_rela; + return lazy; } @@ -194,7 +199,9 @@ _dl_start_user:\n\ # define elf_machine_type_class(type) \ ((((type) == R_X86_64_JUMP_SLOT \ || (type) == R_X86_64_DTPMOD64 \ - || (type) == R_X86_64_DTPOFF64 || (type) == R_X86_64_TPOFF64) \ + || (type) == R_X86_64_DTPOFF64 \ + || (type) == R_X86_64_TPOFF64 \ + || (type) == R_X86_64_TLSDESC) \ * ELF_RTYPE_CLASS_PLT) \ | (((type) == R_X86_64_COPY) * ELF_RTYPE_CLASS_COPY)) #else @@ -323,6 +330,41 @@ elf_machine_rela (struct link_map *map, const Elf64_Rela *reloc, *reloc_addr = sym->st_value + reloc->r_addend; # endif break; + case R_X86_64_TLSDESC: + { + struct tlsdesc volatile *td = + (struct tlsdesc volatile *)reloc_addr; + +# ifndef RTLD_BOOTSTRAP + if (! sym) + { + td->arg = (void*)reloc->r_addend; + td->entry = _dl_tlsdesc_undefweak; + } + else +# endif + { +# ifndef RTLD_BOOTSTRAP +# ifndef SHARED + CHECK_STATIC_TLS (map, sym_map); +# else + if (!TRY_STATIC_TLS (map, sym_map)) + { + td->arg = _dl_make_tlsdesc_dynamic + (sym_map, sym->st_value + reloc->r_addend); + td->entry = _dl_tlsdesc_dynamic; + } + else +# endif +# endif + { + td->arg = (void*)(sym->st_value - sym_map->l_tls_offset + + reloc->r_addend); + td->entry = _dl_tlsdesc_return; + } + } + break; + } case R_X86_64_TPOFF64: /* The offset is negative, forward from the thread pointer. */ # ifndef RTLD_BOOTSTRAP @@ -435,6 +477,15 @@ elf_machine_lazy_rel (struct link_map *map, map->l_mach.plt + (((Elf64_Addr) reloc_addr) - map->l_mach.gotplt) * 2; } + else if (__builtin_expect (r_type == R_X86_64_TLSDESC, 1)) + { + struct tlsdesc volatile * __attribute__((__unused__)) td = + (struct tlsdesc volatile *)reloc_addr; + + td->arg = (void*)reloc; + td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)]) + + map->l_addr); + } else _dl_reloc_bad_type (map, r_type, 1); } diff --git a/sysdeps/x86_64/dl-tls.h b/sysdeps/x86_64/dl-tls.h index 3e4768dc1f..9b389edb4a 100644 --- a/sysdeps/x86_64/dl-tls.h +++ b/sysdeps/x86_64/dl-tls.h @@ -1,5 +1,5 @@ /* Thread-local storage handling in the ELF dynamic linker. x86-64 version. - Copyright (C) 2002 Free Software Foundation, Inc. + Copyright (C) 2002, 2005 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 @@ -19,7 +19,7 @@ /* Type used for the representation of TLS information in the GOT. */ -typedef struct +typedef struct dl_tls_index { unsigned long int ti_module; unsigned long int ti_offset; diff --git a/sysdeps/x86_64/dl-tlsdesc.S b/sysdeps/x86_64/dl-tlsdesc.S new file mode 100644 index 0000000000..5eac1f2a5b --- /dev/null +++ b/sysdeps/x86_64/dl-tlsdesc.S @@ -0,0 +1,245 @@ +/* Thread-local storage handling in the ELF dynamic linker. x86_64 version. + Copyright (C) 2004, 2005, 2008 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <sysdep.h> +#include <tls.h> +#include "tlsdesc.h" + + .text + + /* This function is used to compute the TP offset for symbols in + Static TLS, i.e., whose TP offset is the same for all + threads. + + The incoming %rax points to the TLS descriptor, such that + 0(%rax) points to _dl_tlsdesc_return itself, and 8(%rax) holds + the TP offset of the symbol corresponding to the object + denoted by the argument. */ + + .hidden _dl_tlsdesc_return + .global _dl_tlsdesc_return + .type _dl_tlsdesc_return,@function + cfi_startproc + .align 16 +_dl_tlsdesc_return: + movq 8(%rax), %rax + ret + cfi_endproc + .size _dl_tlsdesc_return, .-_dl_tlsdesc_return + + /* This function is used for undefined weak TLS symbols, for + which the base address (i.e., disregarding any addend) should + resolve to NULL. + + %rax points to the TLS descriptor, such that 0(%rax) points to + _dl_tlsdesc_undefweak itself, and 8(%rax) holds the addend. + We return the addend minus the TP, such that, when the caller + adds TP, it gets the addend back. If that's zero, as usual, + that's most likely a NULL pointer. */ + + .hidden _dl_tlsdesc_undefweak + .global _dl_tlsdesc_undefweak + .type _dl_tlsdesc_undefweak,@function + cfi_startproc + .align 16 +_dl_tlsdesc_undefweak: + movq 8(%rax), %rax + subq %fs:0, %rax + ret + cfi_endproc + .size _dl_tlsdesc_undefweak, .-_dl_tlsdesc_undefweak + +#ifdef SHARED + .hidden _dl_tlsdesc_dynamic + .global _dl_tlsdesc_dynamic + .type _dl_tlsdesc_dynamic,@function + + /* %rax points to the TLS descriptor, such that 0(%rax) points to + _dl_tlsdesc_dynamic itself, and 8(%rax) points to a struct + tlsdesc_dynamic_arg object. It must return in %rax the offset + between the thread pointer and the object denoted by the + argument, without clobbering any registers. + + The assembly code that follows is a rendition of the following + C code, hand-optimized a little bit. + +ptrdiff_t +_dl_tlsdesc_dynamic (register struct tlsdesc *tdp asm ("%rax")) +{ + struct tlsdesc_dynamic_arg *td = tdp->arg; + dtv_t *dtv = *(dtv_t **)((char *)__thread_pointer + DTV_OFFSET); + if (__builtin_expect (td->gen_count <= dtv[0].counter + && (dtv[td->tlsinfo.ti_module].pointer.val + != TLS_DTV_UNALLOCATED), + 1)) + return dtv[td->tlsinfo.ti_module].pointer.val + td->tlsinfo.ti_offset + - __thread_pointer; + + return __tls_get_addr_internal (&td->tlsinfo) - __thread_pointer; +} +*/ + cfi_startproc + .align 16 +_dl_tlsdesc_dynamic: + /* Preserve call-clobbered registers that we modify. + We need two scratch regs anyway. */ + movq %rsi, -16(%rsp) + movq %fs:DTV_OFFSET, %rsi + movq %rdi, -8(%rsp) + movq TLSDESC_ARG(%rax), %rdi + movq (%rsi), %rax + cmpq %rax, TLSDESC_GEN_COUNT(%rdi) + ja .Lslow + movq TLSDESC_MODID(%rdi), %rax + salq $4, %rax + movq (%rax,%rsi), %rax + cmpq $-1, %rax + je .Lslow + addq TLSDESC_MODOFF(%rdi), %rax +.Lret: + movq -16(%rsp), %rsi + subq %fs:0, %rax + movq -8(%rsp), %rdi + ret +.Lslow: + /* Besides rdi and rsi, saved above, save rdx, rcx, r8, r9, + r10 and r11. Also, align the stack, that's off by 8 bytes. */ + subq $72, %rsp + cfi_adjust_cfa_offset (72) + movq %rdx, 8(%rsp) + movq %rcx, 16(%rsp) + movq %r8, 24(%rsp) + movq %r9, 32(%rsp) + movq %r10, 40(%rsp) + movq %r11, 48(%rsp) + /* %rdi already points to the tlsinfo data structure. */ + call __tls_get_addr@PLT + movq 8(%rsp), %rdx + movq 16(%rsp), %rcx + movq 24(%rsp), %r8 + movq 32(%rsp), %r9 + movq 40(%rsp), %r10 + movq 48(%rsp), %r11 + addq $72, %rsp + cfi_adjust_cfa_offset (-72) + jmp .Lret + cfi_endproc + .size _dl_tlsdesc_dynamic, .-_dl_tlsdesc_dynamic +#endif /* SHARED */ + + /* This function is a wrapper for a lazy resolver for TLS_DESC + RELA relocations. The incoming 0(%rsp) points to the caller's + link map, pushed by the dynamic object's internal lazy TLS + resolver front-end before tail-calling us. We need to pop it + ourselves. %rax points to a TLS descriptor, such that 0(%rax) + holds the address of the internal resolver front-end (unless + some other thread beat us to resolving it) and 8(%rax) holds a + pointer to the relocation. + + When the actual resolver returns, it will have adjusted the + TLS descriptor such that we can tail-call it for it to return + the TP offset of the symbol. */ + + .hidden _dl_tlsdesc_resolve_rela + .global _dl_tlsdesc_resolve_rela + .type _dl_tlsdesc_resolve_rela,@function + cfi_startproc + .align 16 + /* The PLT entry will have pushed the link_map pointer. */ +_dl_tlsdesc_resolve_rela: + cfi_adjust_cfa_offset (8) + /* Save all call-clobbered registers. */ + subq $72, %rsp + cfi_adjust_cfa_offset (72) + movq %rax, (%rsp) + movq %rdi, 8(%rsp) + movq %rax, %rdi /* Pass tlsdesc* in %rdi. */ + movq %rsi, 16(%rsp) + movq 72(%rsp), %rsi /* Pass link_map* in %rsi. */ + movq %r8, 24(%rsp) + movq %r9, 32(%rsp) + movq %r10, 40(%rsp) + movq %r11, 48(%rsp) + movq %rdx, 56(%rsp) + movq %rcx, 64(%rsp) + call _dl_tlsdesc_resolve_rela_fixup + movq (%rsp), %rax + movq 8(%rsp), %rdi + movq 16(%rsp), %rsi + movq 24(%rsp), %r8 + movq 32(%rsp), %r9 + movq 40(%rsp), %r10 + movq 48(%rsp), %r11 + movq 56(%rsp), %rdx + movq 64(%rsp), %rcx + addq $80, %rsp + cfi_adjust_cfa_offset (-80) + jmp *(%rax) + cfi_endproc + .size _dl_tlsdesc_resolve_rela, .-_dl_tlsdesc_resolve_rela + + /* This function is a placeholder for lazy resolving of TLS + relocations. Once some thread starts resolving a TLS + relocation, it sets up the TLS descriptor to use this + resolver, such that other threads that would attempt to + resolve it concurrently may skip the call to the original lazy + resolver and go straight to a condition wait. + + When the actual resolver returns, it will have adjusted the + TLS descriptor such that we can tail-call it for it to return + the TP offset of the symbol. */ + + .hidden _dl_tlsdesc_resolve_hold + .global _dl_tlsdesc_resolve_hold + .type _dl_tlsdesc_resolve_hold,@function + cfi_startproc + .align 16 +_dl_tlsdesc_resolve_hold: +0: + /* Save all call-clobbered registers. */ + subq $72, %rsp + cfi_adjust_cfa_offset (72) + movq %rax, (%rsp) + movq %rdi, 8(%rsp) + movq %rax, %rdi /* Pass tlsdesc* in %rdi. */ + movq %rsi, 16(%rsp) + /* Pass _dl_tlsdesc_resolve_hold's address in %rsi. */ + leaq . - _dl_tlsdesc_resolve_hold(%rip), %rsi + movq %r8, 24(%rsp) + movq %r9, 32(%rsp) + movq %r10, 40(%rsp) + movq %r11, 48(%rsp) + movq %rdx, 56(%rsp) + movq %rcx, 64(%rsp) + call _dl_tlsdesc_resolve_hold_fixup +1: + movq (%rsp), %rax + movq 8(%rsp), %rdi + movq 16(%rsp), %rsi + movq 24(%rsp), %r8 + movq 32(%rsp), %r9 + movq 40(%rsp), %r10 + movq 48(%rsp), %r11 + movq 56(%rsp), %rdx + movq 64(%rsp), %rcx + addq $72, %rsp + cfi_adjust_cfa_offset (-72) + jmp *(%eax) + cfi_endproc + .size _dl_tlsdesc_resolve_hold, .-_dl_tlsdesc_resolve_hold diff --git a/sysdeps/x86_64/dl-tlsdesc.h b/sysdeps/x86_64/dl-tlsdesc.h new file mode 100644 index 0000000000..9e64aab5a7 --- /dev/null +++ b/sysdeps/x86_64/dl-tlsdesc.h @@ -0,0 +1,64 @@ +/* Thread-local storage descriptor handling in the ELF dynamic linker. + x86_64 version. + Copyright (C) 2005, 2008 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#ifndef _X86_64_DL_TLSDESC_H +# define _X86_64_DL_TLSDESC_H 1 + +/* Use this to access DT_TLSDESC_PLT and DT_TLSDESC_GOT. */ +#ifndef ADDRIDX +# define ADDRIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \ + + DT_EXTRANUM + DT_VALNUM + DT_ADDRTAGIDX (tag)) +#endif + +/* Type used to represent a TLS descriptor in the GOT. */ +struct tlsdesc +{ + ptrdiff_t (*entry)(struct tlsdesc *on_rax); + void *arg; +}; + +typedef struct dl_tls_index +{ + unsigned long int ti_module; + unsigned long int ti_offset; +} tls_index; + +/* Type used as the argument in a TLS descriptor for a symbol that + needs dynamic TLS offsets. */ +struct tlsdesc_dynamic_arg +{ + tls_index tlsinfo; + size_t gen_count; +}; + +extern ptrdiff_t attribute_hidden + _dl_tlsdesc_return(struct tlsdesc *on_rax), + _dl_tlsdesc_undefweak(struct tlsdesc *on_rax), + _dl_tlsdesc_resolve_rela(struct tlsdesc *on_rax), + _dl_tlsdesc_resolve_hold(struct tlsdesc *on_rax); + +# ifdef SHARED +extern void *internal_function _dl_make_tlsdesc_dynamic (struct link_map *map, + size_t ti_offset); + +extern ptrdiff_t attribute_hidden _dl_tlsdesc_dynamic(struct tlsdesc *); +# endif + +#endif diff --git a/sysdeps/x86_64/tlsdesc.c b/sysdeps/x86_64/tlsdesc.c new file mode 100644 index 0000000000..0cc32aab69 --- /dev/null +++ b/sysdeps/x86_64/tlsdesc.c @@ -0,0 +1,151 @@ +/* Manage TLS descriptors. x86_64 version. + Copyright (C) 2005, 2008 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <link.h> +#include <ldsodefs.h> +#include <elf/dynamic-link.h> +#include <tls.h> +#include <dl-tlsdesc.h> +#include <tlsdeschtab.h> + +/* The following 2 functions take a caller argument, that contains the + address expected to be in the TLS descriptor. If it's changed, we + want to return immediately. */ + +/* This function is used to lazily resolve TLS_DESC RELA relocations. + The argument location is used to hold a pointer to the relocation. */ + +void +attribute_hidden +_dl_tlsdesc_resolve_rela_fixup (struct tlsdesc volatile *td, + struct link_map *l) +{ + const ElfW(Rela) *reloc = td->arg; + + if (_dl_tlsdesc_resolve_early_return_p + (td, (void*)(D_PTR (l, l_info[ADDRIDX (DT_TLSDESC_PLT)]) + l->l_addr))) + return; + + /* The code below was borrowed from _dl_fixup(). */ + 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) *sym = &symtab[ELFW(R_SYM) (reloc->r_info)]; + lookup_t result; + + /* Look up the target symbol. If the normal lookup rules are not + used don't look in the global scope. */ + if (ELFW(ST_BIND) (sym->st_info) != STB_LOCAL + && __builtin_expect (ELFW(ST_VISIBILITY) (sym->st_other), 0) == 0) + { + const struct r_found_version *version = NULL; + + if (l->l_info[VERSYMIDX (DT_VERSYM)] != NULL) + { + const ElfW(Half) *vernum = + (const void *) D_PTR (l, l_info[VERSYMIDX (DT_VERSYM)]); + ElfW(Half) ndx = vernum[ELFW(R_SYM) (reloc->r_info)] & 0x7fff; + version = &l->l_versions[ndx]; + if (version->hash == 0) + version = NULL; + } + + result = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym, + l->l_scope, version, ELF_RTYPE_CLASS_PLT, + DL_LOOKUP_ADD_DEPENDENCY, NULL); + } + else + { + /* We already found the symbol. The module (and therefore its load + address) is also known. */ + result = l; + } + + if (! sym) + { + td->arg = (void*)reloc->r_addend; + td->entry = _dl_tlsdesc_undefweak; + } + else + { +# ifndef SHARED + CHECK_STATIC_TLS (l, result); +# else + if (!TRY_STATIC_TLS (l, result)) + { + td->arg = _dl_make_tlsdesc_dynamic (result, sym->st_value + + reloc->r_addend); + td->entry = _dl_tlsdesc_dynamic; + } + else +# endif + { + td->arg = (void*)(sym->st_value - result->l_tls_offset + + reloc->r_addend); + td->entry = _dl_tlsdesc_return; + } + } + + _dl_tlsdesc_wake_up_held_fixups (); +} + +/* This function is used to avoid busy waiting for other threads to + complete the lazy relocation. Once another thread wins the race to + relocate a TLS descriptor, it sets the descriptor up such that this + function is called to wait until the resolver releases the + lock. */ + +void +attribute_hidden +_dl_tlsdesc_resolve_hold_fixup (struct tlsdesc volatile *td, + void *caller) +{ + /* Maybe we're lucky and can return early. */ + if (caller != td->entry) + return; + + /* Locking here will stop execution until the running resolver runs + _dl_tlsdesc_wake_up_held_fixups(), releasing the lock. + + FIXME: We'd be better off waiting on a condition variable, such + that we didn't have to hold the lock throughout the relocation + processing. */ + __rtld_lock_lock_recursive (GL(dl_load_lock)); + __rtld_lock_unlock_recursive (GL(dl_load_lock)); +} + +/* Unmap the dynamic object, but also release its TLS descriptor table + if there is one. */ + +void +internal_function +_dl_unmap (struct link_map *map) +{ + __munmap ((void *) (map)->l_map_start, + (map)->l_map_end - (map)->l_map_start); + +#if SHARED + /* _dl_unmap is only called for dlopen()ed libraries, for which + calling free() is safe, or before we've completed the initial + relocation, in which case calling free() is probably pointless, + but still safe. */ + if (map->l_mach.tlsdesc_table) + htab_delete (map->l_mach.tlsdesc_table); +#endif +} diff --git a/sysdeps/x86_64/tlsdesc.sym b/sysdeps/x86_64/tlsdesc.sym new file mode 100644 index 0000000000..33854975d0 --- /dev/null +++ b/sysdeps/x86_64/tlsdesc.sym @@ -0,0 +1,17 @@ +#include <stddef.h> +#include <sysdep.h> +#include <tls.h> +#include <link.h> +#include <dl-tlsdesc.h> + +-- + +-- Abuse tls.h macros to derive offsets relative to the thread register. + +DTV_OFFSET offsetof(struct pthread, header.dtv) + +TLSDESC_ARG offsetof(struct tlsdesc, arg) + +TLSDESC_GEN_COUNT offsetof(struct tlsdesc_dynamic_arg, gen_count) +TLSDESC_MODID offsetof(struct tlsdesc_dynamic_arg, tlsinfo.ti_module) +TLSDESC_MODOFF offsetof(struct tlsdesc_dynamic_arg, tlsinfo.ti_offset) |