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authorJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
commit0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (patch)
tree2ea1f8305970753e4a657acb2ccc15ca3eec8e2c /sysdeps/alpha/dl-machine.h
parent7d58530341304d403a6626d7f7a1913165fe2f32 (diff)
2.5-18.1
Diffstat (limited to 'sysdeps/alpha/dl-machine.h')
-rw-r--r--sysdeps/alpha/dl-machine.h309
1 files changed, 74 insertions, 235 deletions
diff --git a/sysdeps/alpha/dl-machine.h b/sysdeps/alpha/dl-machine.h
index 780a3a57fd..88c357ea07 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 Free Software Foundation, Inc.
+ Copyright (C) 1996-2002, 2003, 2004, 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <rth@tamu.edu>.
@@ -33,6 +33,9 @@
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)
@@ -55,244 +58,77 @@ elf_machine_dynamic (void)
}
/* Return the run-time load address of the shared object. */
+
static inline Elf64_Addr
elf_machine_load_address (void)
{
- /* 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);
+ /* This relies on the compiler using gp-relative addresses for static symbols. */
+ static void *dot = &dot;
+ return (void *)&dot - dot;
}
/* 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 *l, int lazy, int profile)
+elf_machine_runtime_setup (struct link_map *map, int lazy, int profile)
{
- Elf64_Addr plt;
- extern void _dl_runtime_resolve (void);
- extern void _dl_runtime_profile (void);
+ 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;
- if (l->l_info[DT_JMPREL] && lazy)
+ if (__builtin_expect (profile, 0))
{
- /* 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;
+ if (secureplt)
+ resolve = _dl_runtime_profile_new;
else
- {
- *(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;
+ resolve = _dl_runtime_profile_old;
- /* 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)
+ if (GLRO(dl_profile) && _dl_name_match_p (GLRO(dl_profile), 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;
- }
+ /* This is the object we are looking for. Say that we really
+ want profiling and the timers are started. */
+ GL(dl_profile_map) = map;
}
}
+ 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. */
@@ -416,7 +252,7 @@ $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 *l, lookup_t t,
+elf_machine_fixup_plt (struct link_map *map, lookup_t t,
const Elf64_Rela *reloc,
Elf64_Addr *got_addr, Elf64_Addr value)
{
@@ -427,10 +263,16 @@ elf_machine_fixup_plt (struct link_map *l, 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 = (void *) D_PTR (l, l_info[DT_JMPREL]);
- plte = (void *) (D_PTR (l, l_info[DT_PLTGOT]) + 32);
+ rela_plt = (const Elf64_Rela *) D_PTR (map, l_info[DT_JMPREL]);
+ plte = (Elf64_Word *) (D_PTR (map, l_info[DT_PLTGOT]) + 32);
plte += 3 * (reloc - rela_plt);
/* Find the displacement from the plt entry to the function. */
@@ -501,13 +343,18 @@ 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
+#ifdef RESOLVE_MAP
/* 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,
@@ -555,26 +402,16 @@ 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)
+ if (sym_map)
{
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;
@@ -646,6 +483,7 @@ 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)
{
@@ -662,6 +500,7 @@ 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)
{
@@ -680,4 +519,4 @@ elf_machine_lazy_rel (struct link_map *map,
_dl_reloc_bad_type (map, r_type, 1);
}
-#endif /* RESOLVE */
+#endif /* RESOLVE_MAP */