diff options
Diffstat (limited to 'sysdeps/alpha/dl-machine.h')
| -rw-r--r-- | sysdeps/alpha/dl-machine.h | 309 |
1 files changed, 235 insertions, 74 deletions
diff --git a/sysdeps/alpha/dl-machine.h b/sysdeps/alpha/dl-machine.h index 88c357ea07..780a3a57fd 100644 --- a/sysdeps/alpha/dl-machine.h +++ b/sysdeps/alpha/dl-machine.h @@ -1,5 +1,5 @@ /* Machine-dependent ELF dynamic relocation inline functions. Alpha version. - Copyright (C) 1996-2002, 2003, 2004, 2005 Free Software Foundation, Inc. + Copyright (C) 1996-2002, 2003, 2004 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Richard Henderson <rth@tamu.edu>. @@ -33,9 +33,6 @@ where the dynamic linker should not map anything. */ #define ELF_MACHINE_USER_ADDRESS_MASK 0x120000000UL -/* Translate a processor specific dynamic tag to the index in l_info array. */ -#define DT_ALPHA(x) (DT_ALPHA_##x - DT_LOPROC + DT_NUM) - /* Return nonzero iff ELF header is compatible with the running host. */ static inline int elf_machine_matches_host (const Elf64_Ehdr *ehdr) @@ -58,77 +55,244 @@ elf_machine_dynamic (void) } /* Return the run-time load address of the shared object. */ - static inline Elf64_Addr elf_machine_load_address (void) { - /* This relies on the compiler using gp-relative addresses for static symbols. */ - static void *dot = ˙ - return (void *)&dot - dot; + /* NOTE: While it is generally unfriendly to put data in the text + segment, it is only slightly less so when the "data" is an + instruction. While we don't have to worry about GLD just yet, an + optimizing linker might decide that our "data" is an unreachable + instruction and throw it away -- with the right switches, DEC's + linker will do this. What ought to happen is we should add + something to GAS to allow us access to the new GPREL_HI32/LO32 + relocation types stolen from OSF/1 3.0. */ + /* This code relies on the fact that BRADDR relocations do not + appear in dynamic relocation tables. Not that that would be very + useful anyway -- br/bsr has a 4MB range and the shared libraries + are usually many many terabytes away. */ + + Elf64_Addr dot; + long int zero_disp; + + asm("br %0, 1f\n" + "0:\n\t" + "br $0, 2f\n" + "1:\n\t" + ".section\t.data\n" + "2:\n\t" + ".quad 0b\n\t" + ".previous" + : "=r"(dot)); + + zero_disp = *(int *) dot; + zero_disp = (zero_disp << 43) >> 41; + + return dot - *(Elf64_Addr *) (dot + 4 + zero_disp); } /* 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 -elf_machine_runtime_setup (struct link_map *map, int lazy, int profile) +elf_machine_runtime_setup (struct link_map *l, int lazy, int profile) { - extern char _dl_runtime_resolve_new[] attribute_hidden; - extern char _dl_runtime_profile_new[] attribute_hidden; - extern char _dl_runtime_resolve_old[] attribute_hidden; - extern char _dl_runtime_profile_old[] attribute_hidden; - - struct pltgot { - char *resolve; - struct link_map *link; - }; - - struct pltgot *pg; - long secureplt; - char *resolve; - - if (map->l_info[DT_JMPREL] == 0 || !lazy) - return lazy; - - /* Check to see if we're using the read-only plt form. */ - secureplt = map->l_info[DT_ALPHA(PLTRO)] != 0; - - /* If the binary uses the read-only secure plt format, PG points to - the .got.plt section, which is the right place for ld.so to place - its hooks. Otherwise, PG is currently pointing at the start of - the plt; the hooks go at offset 16. */ - pg = (struct pltgot *) D_PTR (map, l_info[DT_PLTGOT]); - pg += !secureplt; - - /* This function will be called to perform the relocation. They're - not declared as functions to convince the compiler to use gp - relative relocations for them. */ - if (secureplt) - resolve = _dl_runtime_resolve_new; - else - resolve = _dl_runtime_resolve_old; + Elf64_Addr plt; + extern void _dl_runtime_resolve (void); + extern void _dl_runtime_profile (void); - if (__builtin_expect (profile, 0)) + if (l->l_info[DT_JMPREL] && lazy) { - if (secureplt) - resolve = _dl_runtime_profile_new; + /* The GOT entries for the functions in the PLT have not been + filled in yet. Their initial contents are directed to the + PLT which arranges for the dynamic linker to be called. */ + plt = D_PTR (l, l_info[DT_PLTGOT]); + + /* This function will be called to perform the relocation. */ + if (!profile) + *(Elf64_Addr *)(plt + 16) = (Elf64_Addr) &_dl_runtime_resolve; else - resolve = _dl_runtime_profile_old; + { + *(Elf64_Addr *)(plt + 16) = (Elf64_Addr) &_dl_runtime_profile; + + if (_dl_name_match_p (GLRO(dl_profile), l)) + { + /* This is the object we are looking for. Say that we really + want profiling and the timers are started. */ + GL(dl_profile_map) = l; + } + } + + /* Identify this shared object */ + *(Elf64_Addr *)(plt + 24) = (Elf64_Addr) l; - if (GLRO(dl_profile) && _dl_name_match_p (GLRO(dl_profile), map)) + /* If the first instruction of the plt entry is not + "br $28, plt0", we have to reinitialize .plt for lazy relocation. */ + if (*(unsigned int *)(plt + 32) != 0xc39ffff7) { - /* This is the object we are looking for. Say that we really - want profiling and the timers are started. */ - GL(dl_profile_map) = map; + unsigned int val = 0xc39ffff7; + unsigned int *slot, *end; + const Elf64_Rela *rela = (const Elf64_Rela *) + D_PTR (l, l_info[DT_JMPREL]); + Elf64_Addr l_addr = l->l_addr; + + /* br t12,.+4; ldq t12,12(t12); nop; jmp t12,(t12),.+4 */ + *(unsigned long *)plt = 0xa77b000cc3600000; + *(unsigned long *)(plt + 8) = 0x6b7b000047ff041f; + slot = (unsigned int *)(plt + 32); + end = (unsigned int *)(plt + 32 + + l->l_info[DT_PLTRELSZ]->d_un.d_val / 2); + while (slot < end) + { + /* br at,.plt+0 */ + *slot = val; + *(Elf64_Addr *) rela->r_offset = (Elf64_Addr) slot - l_addr; + val -= 3; + slot += 3; + ++rela; + } } } - pg->resolve = resolve; - pg->link = map; - return lazy; } +/* This code is used in dl-runtime.c to call the `fixup' function + and then redirect to the address it returns. */ +#define TRAMPOLINE_TEMPLATE(tramp_name, fixup_name, IMB) \ + extern void tramp_name (void); \ + asm ( "\ + .globl " #tramp_name " \n\ + .ent " #tramp_name " \n\ +" #tramp_name ": \n\ + lda $sp, -44*8($sp) \n\ + .frame $sp, 44*8, $26 \n\ + /* Preserve all integer registers that C normally \n\ + doesn't. */ \n\ + stq $26, 0*8($sp) \n\ + stq $0, 1*8($sp) \n\ + stq $1, 2*8($sp) \n\ + stq $2, 3*8($sp) \n\ + stq $3, 4*8($sp) \n\ + stq $4, 5*8($sp) \n\ + stq $5, 6*8($sp) \n\ + stq $6, 7*8($sp) \n\ + stq $7, 8*8($sp) \n\ + stq $8, 9*8($sp) \n\ + stq $16, 10*8($sp) \n\ + stq $17, 11*8($sp) \n\ + stq $18, 12*8($sp) \n\ + stq $19, 13*8($sp) \n\ + stq $20, 14*8($sp) \n\ + stq $21, 15*8($sp) \n\ + stq $22, 16*8($sp) \n\ + stq $23, 17*8($sp) \n\ + stq $24, 18*8($sp) \n\ + stq $25, 19*8($sp) \n\ + stq $29, 20*8($sp) \n\ + stt $f0, 21*8($sp) \n\ + stt $f1, 22*8($sp) \n\ + stt $f10, 23*8($sp) \n\ + stt $f11, 24*8($sp) \n\ + stt $f12, 25*8($sp) \n\ + stt $f13, 26*8($sp) \n\ + stt $f14, 27*8($sp) \n\ + stt $f15, 28*8($sp) \n\ + stt $f16, 29*8($sp) \n\ + stt $f17, 30*8($sp) \n\ + stt $f18, 31*8($sp) \n\ + stt $f19, 32*8($sp) \n\ + stt $f20, 33*8($sp) \n\ + stt $f21, 34*8($sp) \n\ + stt $f22, 35*8($sp) \n\ + stt $f23, 36*8($sp) \n\ + stt $f24, 37*8($sp) \n\ + stt $f25, 38*8($sp) \n\ + stt $f26, 39*8($sp) \n\ + stt $f27, 40*8($sp) \n\ + stt $f28, 41*8($sp) \n\ + stt $f29, 42*8($sp) \n\ + stt $f30, 43*8($sp) \n\ + .mask 0x27ff01ff, -44*8 \n\ + .fmask 0xfffffc03, -(44-21)*8 \n\ + /* Set up our $gp */ \n\ + br $gp, .+4 \n\ + ldgp $gp, 0($gp) \n\ + .prologue 0 \n\ + /* Set up the arguments for fixup: */ \n\ + /* $16 = link_map out of plt0 */ \n\ + /* $17 = offset of reloc entry = ($28 - $27 - 20) /12 * 24 */\n\ + /* $18 = return address */ \n\ + subq $28, $27, $17 \n\ + ldq $16, 8($27) \n\ + subq $17, 20, $17 \n\ + mov $26, $18 \n\ + addq $17, $17, $17 \n\ + /* Do the fixup */ \n\ + bsr $26, " #fixup_name " !samegp \n\ + /* Move the destination address into position. */ \n\ + mov $0, $27 \n\ + /* Restore program registers. */ \n\ + ldq $26, 0*8($sp) \n\ + ldq $0, 1*8($sp) \n\ + ldq $1, 2*8($sp) \n\ + ldq $2, 3*8($sp) \n\ + ldq $3, 4*8($sp) \n\ + ldq $4, 5*8($sp) \n\ + ldq $5, 6*8($sp) \n\ + ldq $6, 7*8($sp) \n\ + ldq $7, 8*8($sp) \n\ + ldq $8, 9*8($sp) \n\ + ldq $16, 10*8($sp) \n\ + ldq $17, 11*8($sp) \n\ + ldq $18, 12*8($sp) \n\ + ldq $19, 13*8($sp) \n\ + ldq $20, 14*8($sp) \n\ + ldq $21, 15*8($sp) \n\ + ldq $22, 16*8($sp) \n\ + ldq $23, 17*8($sp) \n\ + ldq $24, 18*8($sp) \n\ + ldq $25, 19*8($sp) \n\ + ldq $29, 20*8($sp) \n\ + ldt $f0, 21*8($sp) \n\ + ldt $f1, 22*8($sp) \n\ + ldt $f10, 23*8($sp) \n\ + ldt $f11, 24*8($sp) \n\ + ldt $f12, 25*8($sp) \n\ + ldt $f13, 26*8($sp) \n\ + ldt $f14, 27*8($sp) \n\ + ldt $f15, 28*8($sp) \n\ + ldt $f16, 29*8($sp) \n\ + ldt $f17, 30*8($sp) \n\ + ldt $f18, 31*8($sp) \n\ + ldt $f19, 32*8($sp) \n\ + ldt $f20, 33*8($sp) \n\ + ldt $f21, 34*8($sp) \n\ + ldt $f22, 35*8($sp) \n\ + ldt $f23, 36*8($sp) \n\ + ldt $f24, 37*8($sp) \n\ + ldt $f25, 38*8($sp) \n\ + ldt $f26, 39*8($sp) \n\ + ldt $f27, 40*8($sp) \n\ + ldt $f28, 41*8($sp) \n\ + ldt $f29, 42*8($sp) \n\ + ldt $f30, 43*8($sp) \n\ + /* Flush the Icache after having modified the .plt code. */\n\ + " #IMB " \n\ + /* Clean up and turn control to the destination */ \n\ + lda $sp, 44*8($sp) \n\ + jmp $31, ($27) \n\ + .end " #tramp_name) + +#ifndef PROF +#define ELF_MACHINE_RUNTIME_TRAMPOLINE \ + TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup, imb); \ + TRAMPOLINE_TEMPLATE (_dl_runtime_profile, profile_fixup, /* nop */); +#else +#define ELF_MACHINE_RUNTIME_TRAMPOLINE \ + TRAMPOLINE_TEMPLATE (_dl_runtime_resolve, fixup, imb); \ + strong_alias (_dl_runtime_resolve, _dl_runtime_profile); +#endif + /* 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. */ @@ -252,7 +416,7 @@ $fixup_stack: \n\ /* Fix up the instructions of a PLT entry to invoke the function rather than the dynamic linker. */ static inline Elf64_Addr -elf_machine_fixup_plt (struct link_map *map, lookup_t t, +elf_machine_fixup_plt (struct link_map *l, lookup_t t, const Elf64_Rela *reloc, Elf64_Addr *got_addr, Elf64_Addr value) { @@ -263,16 +427,10 @@ elf_machine_fixup_plt (struct link_map *map, lookup_t t, /* Store the value we are going to load. */ *got_addr = value; - /* If this binary uses the read-only secure plt format, we're done. */ - if (map->l_info[DT_ALPHA(PLTRO)]) - return value; - - /* Otherwise we have to modify the plt entry in place to do the branch. */ - /* Recover the PLT entry address by calculating reloc's index into the .rela.plt, and finding that entry in the .plt. */ - rela_plt = (const Elf64_Rela *) D_PTR (map, l_info[DT_JMPREL]); - plte = (Elf64_Word *) (D_PTR (map, l_info[DT_PLTGOT]) + 32); + rela_plt = (void *) D_PTR (l, l_info[DT_JMPREL]); + plte = (void *) (D_PTR (l, l_info[DT_PLTGOT]) + 32); plte += 3 * (reloc - rela_plt); /* Find the displacement from the plt entry to the function. */ @@ -343,18 +501,13 @@ elf_machine_plt_value (struct link_map *map, const Elf64_Rela *reloc, return value + reloc->r_addend; } -/* Names of the architecture-specific auditing callback functions. */ -#define ARCH_LA_PLTENTER alpha_gnu_pltenter -#define ARCH_LA_PLTEXIT alpha_gnu_pltexit - #endif /* !dl_machine_h */ -#ifdef RESOLVE_MAP +#ifdef RESOLVE /* Perform the relocation specified by RELOC and SYM (which is fully resolved). MAP is the object containing the reloc. */ auto inline void -__attribute__ ((always_inline)) elf_machine_rela (struct link_map *map, const Elf64_Rela *reloc, const Elf64_Sym *sym, @@ -402,16 +555,26 @@ elf_machine_rela (struct link_map *map, return; else { - struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type); Elf64_Addr sym_value; Elf64_Addr sym_raw_value; +#if defined USE_TLS && !defined RTLD_BOOTSTRAP + struct link_map *sym_map = RESOLVE_MAP (&sym, version, r_type); sym_raw_value = sym_value = reloc->r_addend; - if (sym_map) + if (sym) { sym_raw_value += sym->st_value; sym_value = sym_raw_value + sym_map->l_addr; } +#else + Elf64_Addr loadbase = RESOLVE (&sym, version, r_type); + sym_raw_value = sym_value = reloc->r_addend; + if (sym) + { + sym_raw_value += sym->st_value; + sym_value = sym_raw_value + loadbase; + } +#endif if (r_type == R_ALPHA_GLOB_DAT) *reloc_addr = sym_value; @@ -483,7 +646,6 @@ elf_machine_rela (struct link_map *map, #define ELF_MACHINE_REL_RELATIVE 1 auto inline void -__attribute__ ((always_inline)) elf_machine_rela_relative (Elf64_Addr l_addr, const Elf64_Rela *reloc, void *const reloc_addr_arg) { @@ -500,7 +662,6 @@ elf_machine_rela_relative (Elf64_Addr l_addr, const Elf64_Rela *reloc, } auto inline void -__attribute__ ((always_inline)) elf_machine_lazy_rel (struct link_map *map, Elf64_Addr l_addr, const Elf64_Rela *reloc) { @@ -519,4 +680,4 @@ elf_machine_lazy_rel (struct link_map *map, _dl_reloc_bad_type (map, r_type, 1); } -#endif /* RESOLVE_MAP */ +#endif /* RESOLVE */ |