/* Machine-dependent ELF dynamic relocation inline functions.   PowerPC64 version.   Copyright 1995-2005, 2006 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 Library General Public License as   published by the Free Software Foundation; either version 2 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   Library General Public License for more details.   You should have received a copy of the GNU Library General Public   License along with the GNU C Library; see the file COPYING.LIB.  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 "powerpc64"#include <assert.h>#include <sys/param.h>#include <dl-tls.h>#include <sysdep.h>/* Translate a processor specific dynamic tag to the index   in l_info array.  */#define DT_PPC64(x) (DT_PPC64_##x - DT_LOPROC + DT_NUM)/* A PowerPC64 function descriptor.  The .plt (procedure linkage   table) and .opd (official procedure descriptor) sections are   arrays of these.  */typedef struct{  Elf64_Addr fd_func;  Elf64_Addr fd_toc;  Elf64_Addr fd_aux;} Elf64_FuncDesc;#define ELF_MULT_MACHINES_SUPPORTED/* Return nonzero iff ELF header is compatible with the running host.  */static inline intelf_machine_matches_host (const Elf64_Ehdr *ehdr){  return ehdr->e_machine == EM_PPC64;}/* Return nonzero iff ELF header is compatible with the running host,   but not this loader.  */static inline intelf_host_tolerates_machine (const Elf64_Ehdr *ehdr){  return ehdr->e_machine == EM_PPC;}/* Return nonzero iff ELF header is compatible with the running host,   but not this loader.  */static inline intelf_host_tolerates_class (const Elf64_Ehdr *ehdr){  return ehdr->e_ident[EI_CLASS] == ELFCLASS32;}/* Return the run-time load address of the shared object, assuming it   was originally linked at zero.  */static inline Elf64_Addrelf_machine_load_address (void) __attribute__ ((const));static inline Elf64_Addrelf_machine_load_address (void){  Elf64_Addr ret;  /* The first entry in .got (and thus the first entry in .toc) is the     link-time TOC_base, ie. r2.  So the difference between that and     the current r2 set by the kernel is how far the shared lib has     moved.  */  asm (	"	ld	%0,-32768(2)\n"	"	subf	%0,%0,2\n"	: "=r"	(ret));  return ret;}/* Return the link-time address of _DYNAMIC.  */static inline Elf64_Addrelf_machine_dynamic (void){  Elf64_Addr runtime_dynamic;  /* It's easier to get the run-time address.  */  asm (	"	addis	%0,2,_DYNAMIC@toc@ha\n"	"	addi	%0,%0,_DYNAMIC@toc@l\n"	: "=b"	(runtime_dynamic));  /* Then subtract off the load address offset.  */  return runtime_dynamic - elf_machine_load_address() ;}#define ELF_MACHINE_BEFORE_RTLD_RELOC(dynamic_info) /* nothing *//* The PLT uses Elf64_Rela relocs.  */#define elf_machine_relplt elf_machine_rela#ifdef HAVE_INLINED_SYSCALLS/* We do not need _dl_starting_up.  */# define DL_STARTING_UP_DEF#else# define DL_STARTING_UP_DEF \".LC__dl_starting_up:\n"  \"	.tc _dl_starting_up_internal[TC],_dl_starting_up_internal\n"#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.  */#define RTLD_START \  asm (".pushsection \".text\"\n"					\"	.align	2\n"							\"	.type	" BODY_PREFIX "_start,@function\n"			\"	.pushsection \".opd\",\"aw\"\n"					\"	.align	3\n"							\"	.globl	_start\n"						\"	" ENTRY_2(_start) "\n"						\"_start:\n"								\"	" OPD_ENT(_start) "\n"						\"	.popsection\n"							\BODY_PREFIX "_start:\n"							\/* We start with the following on the stack, from top:			\   argc (4 bytes);							\   arguments for program (terminated by NULL);				\   environment variables (terminated by NULL);				\   arguments for the program loader.  */				\"	mr	3,1\n"							\"	li	4,0\n"							\"	stdu	4,-128(1)\n"						\/* Call _dl_start with one parameter pointing at argc.  */		\"	bl	" DOT_PREFIX "_dl_start\n"				\"	nop\n"								\/* Transfer control to _dl_start_user!  */				\"	b	" DOT_PREFIX "_dl_start_user\n"				\".LT__start:\n"								\"	.long 0\n"							\"	.byte 0x00,0x0c,0x24,0x40,0x00,0x00,0x00,0x00\n"		\"	.long .LT__start-" BODY_PREFIX "_start\n"			\"	.short .LT__start_name_end-.LT__start_name_start\n"		\".LT__start_name_start:\n"						\"	.ascii \"_start\"\n"						\".LT__start_name_end:\n"						\"	.align 2\n"							\"	" END_2(_start) "\n"						\"	.globl	_dl_start_user\n"					\"	.pushsection \".opd\",\"aw\"\n"					\"_dl_start_user:\n"							\"	" OPD_ENT(_dl_start_user) "\n"					\"	.popsection\n"							\"	.pushsection	\".toc\",\"aw\"\n"				\DL_STARTING_UP_DEF							\".LC__rtld_global:\n"							\"	.tc _rtld_global[TC],_rtld_global\n"				\".LC__dl_argc:\n"							\"	.tc _dl_argc[TC],_dl_argc\n"					\".LC__dl_argv:\n"							\"	.tc _dl_argv_internal[TC],_dl_argv_internal\n"			\".LC__dl_fini:\n"							\"	.tc _dl_fini[TC],_dl_fini\n"					\"	.popsection\n"							\"	.type	" BODY_PREFIX "_dl_start_user,@function\n"		\"	" ENTRY_2(_dl_start_user) "\n"					\/* Now, we do our main work of calling initialisation procedures.	\   The ELF ABI doesn't say anything about parameters for these,		\   so we just pass argc, argv, and the environment.			\   Changing these is strongly discouraged (not least because argc is	\   passed by value!).  */						\BODY_PREFIX "_dl_start_user:\n"						\/* the address of _start in r30.  */					\"	mr	30,3\n"							\/* &_dl_argc in 29, &_dl_argv in 27, and _dl_loaded in 28.  */		\"	ld	28,.LC__rtld_global@toc(2)\n"				\"	ld	29,.LC__dl_argc@toc(2)\n"				\"	ld	27,.LC__dl_argv@toc(2)\n"				\/* _dl_init (_dl_loaded, _dl_argc, _dl_argv, _dl_argv+_dl_argc+1).  */	\"	ld	3,0(28)\n"						\"	lwa	4,0(29)\n"						\"	ld	5,0(27)\n"						\"	sldi	6,4,3\n"						\"	add	6,5,6\n"						\"	addi	6,6,8\n"						\"	bl	" DOT_PREFIX "_dl_init\n"				\"	nop\n"								\/* Now, to conform to the ELF ABI, we have to:				\   Pass argc (actually _dl_argc) in r3;  */				\"	lwa	3,0(29)\n"						\/* Pass argv (actually _dl_argv) in r4;  */				\"	ld	4,0(27)\n"						\/* Pass argv+argc+1 in r5;  */						\"	sldi	5,3,3\n"						\"	add	6,4,5\n"						\"	addi	5,6,8\n"						\/* Pass the auxilary vector in r6. This is passed to us just after	\   _envp.  */								\"2:	ldu	0,8(6)\n"						\"	cmpdi	0,0\n"							\"	bne	2b\n"							\"	addi	6,6,8\n"						\/* Pass a termination function pointer (in this case _dl_fini) in	\   r7.  */								\"	ld	7,.LC__dl_fini@toc(2)\n"				\/* Pass the stack pointer in r1 (so far so good), pointing to a NULL	\   value.  This lets our startup code distinguish between a program	\   linked statically, which linux will call with argc on top of the	\   stack which will hopefully never be zero, and a dynamically linked	\   program which will always have a NULL on the top of the stack.	\   Take the opportunity to clear LR, so anyone who accidentally		\   returns from _start gets SEGV.  Also clear the next few words of	\   the stack.  */							\"	li	31,0\n"							\"	std	31,0(1)\n"						\"	mtlr	31\n"							\"	std	31,8(1)\n"						\"	std	31,16(1)\n"						\"	std	31,24(1)\n"						\/* Now, call the start function descriptor at r30...  */		\"	.globl	._dl_main_dispatch\n"					\"._dl_main_dispatch:\n"							\"	ld	0,0(30)\n"						\"	ld	2,8(30)\n"						\"	mtctr	0\n"							\"	ld	11,16(30)\n"						\"	bctr\n"								\".LT__dl_start_user:\n"							\"	.long 0\n"							\"	.byte 0x00,0x0c,0x24,0x40,0x00,0x00,0x00,0x00\n"		\"	.long .LT__dl_start_user-" BODY_PREFIX "_dl_start_user\n"	\"	.short .LT__dl_start_user_name_end-.LT__dl_start_user_name_start\n" \".LT__dl_start_user_name_start:\n"					\"	.ascii \"_dl_start_user\"\n"					\".LT__dl_start_user_name_end:\n"					\"	.align 2\n"							\"	" END_2(_dl_start_user) "\n"					\"	.popsection");/* Nonzero iff TYPE should not be allowed to resolve to one of   the main executable's symbols, as for a COPY reloc.  */#define elf_machine_lookup_noexec_p(type) ((type) == R_PPC64_COPY)/* Nonzero iff TYPE describes relocation of a PLT entry, so   PLT entries should not be allowed to define the value.  */#define elf_machine_lookup_noplt_p(type) ((type) == R_PPC64_JMP_SLOT)/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry, so   PLT entries should not be allowed to define the value.   ELF_RTYPE_CLASS_NOCOPY iff TYPE should not be allowed to resolve to one   of the main executable's symbols, as for a COPY reloc.  */#if !defined RTLD_BOOTSTRAP || USE___THREAD#define elf_machine_type_class(type)					      \  /* This covers all the TLS relocs, though most won't appear.  */	      \  (((((type) >= R_PPC64_DTPMOD64 && (type) <= R_PPC64_TPREL16_HIGHESTA)	      \    || (type) == R_PPC64_ADDR24) * ELF_RTYPE_CLASS_PLT)			      \   | (((type) == R_PPC64_COPY) * ELF_RTYPE_CLASS_COPY))#else#define elf_machine_type_class(type) \  ((((type) == R_PPC64_ADDR24) * ELF_RTYPE_CLASS_PLT)	\   | (((type) == R_PPC64_COPY) * ELF_RTYPE_CLASS_COPY))#endif/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries.  */#define ELF_MACHINE_JMP_SLOT	R_PPC64_JMP_SLOT/* The PowerPC never uses REL relocations.  */#define ELF_MACHINE_NO_REL 1/* Stuff for the PLT.  */#define PLT_INITIAL_ENTRY_WORDS 3#define GLINK_INITIAL_ENTRY_WORDS 8#define PPC_DCBST(where) asm volatile ("dcbst 0,%0" : : "r"(where) : "memory")#define PPC_SYNC asm volatile ("sync" : : : "memory")#define PPC_ISYNC asm volatile ("sync; isync" : : : "memory")#define PPC_ICBI(where) asm volatile ("icbi 0,%0" : : "r"(where) : "memory")#define PPC_DIE asm volatile ("tweq 0,0")/* Use this when you've modified some code, but it won't be in the   instruction fetch queue (or when it doesn't matter if it is). */#define MODIFIED_CODE_NOQUEUE(where) \     do { PPC_DCBST(where); PPC_SYNC; PPC_ICBI(where); } while (0)/* Use this when it might be in the instruction queue. */#define MODIFIED_CODE(where) \     do { PPC_DCBST(where); PPC_SYNC; PPC_ICBI(where); PPC_ISYNC; } while (0)/* Set up the loaded object described by MAP so its unrelocated PLT   entries will jump to the on-demand fixup code in dl-runtime.c.  */static inline int __attribute__ ((always_inline))elf_machine_runtime_setup (struct link_map *map, int lazy, int profile){  if (map->l_info[DT_JMPREL])    {      Elf64_Word i;      Elf64_Word *glink = NULL;      Elf64_Xword *plt = (Elf64_Xword *) D_PTR (map, l_info[DT_PLTGOT]);      Elf64_Word num_plt_entries = (map->l_info[DT_PLTRELSZ]->d_un.d_val				    / sizeof (Elf64_Rela));      Elf64_Addr l_addr = map->l_addr;      Elf64_Dyn **info = map->l_info;      char *p;      extern void _dl_runtime_resolve (void);      extern void _dl_profile_resolve (void);      /* Relocate the DT_PPC64_GLINK entry in the _DYNAMIC section.	 elf_get_dynamic_info takes care of the standard entries but	 doesn't know exactly what to do with processor specific	 entires.  */      if (info[DT_PPC64(GLINK)] != NULL)	info[DT_PPC64(GLINK)]->d_un.d_ptr += l_addr;      if (lazy)	{	  /* The function descriptor of the appropriate trampline	     routine is used to set the 1st and 2nd doubleword of the	     plt_reserve.  */	  Elf64_FuncDesc *resolve_fd;	  Elf64_Word glink_offset;	  /* the plt_reserve area is the 1st 3 doublewords of the PLT */	  Elf64_FuncDesc *plt_reserve = (Elf64_FuncDesc *) plt;	  Elf64_Word offset;	  resolve_fd = (Elf64_FuncDesc *) (profile ? _dl_profile_resolve					   : _dl_runtime_resolve);	  if (profile && GLRO(dl_profile) != NULL	      && _dl_name_match_p (GLRO(dl_profile), map))	    /* This is the object we are looking for.  Say that we really	       want profiling and the timers are started.  */	    GL(dl_profile_map) = map;	  /* We need to stuff the address/TOC of _dl_runtime_resolve	     into doublewords 0 and 1 of plt_reserve.  Then we need to	     stuff the map address into doubleword 2 of plt_reserve.	     This allows the GLINK0 code to transfer control to the	     correct trampoline which will transfer control to fixup	     in dl-machine.c.  */	  plt_reserve->fd_func = resolve_fd->fd_func;	  plt_reserve->fd_toc  = resolve_fd->fd_toc;	  plt_reserve->fd_aux  = (Elf64_Addr) map;#ifdef RTLD_BOOTSTRAP	  /* When we're bootstrapping, the opd entry will not have	     been relocated yet.  */	  plt_reserve->fd_func += l_addr;	  plt_reserve->fd_toc  += l_addr;#endif	  /* Set up the lazy PLT entries.  */	  glink = (Elf64_Word *) D_PTR (map, l_info[DT_PPC64(GLINK)]);	  offset = PLT_INITIAL_ENTRY_WORDS;	  glink_offset = GLINK_INITIAL_ENTRY_WORDS;	  for (i = 0; i < num_plt_entries; i++)	    {	      plt[offset] = (Elf64_Xword) &glink[glink_offset];	      offset += 3;	      /* The first 32k entries of glink can set an index and		 branch using two instructions;  Past that point,		 glink uses three instructions.  */	      if (i < 0x8000)          	glink_offset += 2;	      else          	glink_offset += 3;	    }	  /* Now, we've modified data.  We need to write the changes from	     the data cache to a second-level unified cache, then make	     sure that stale data in the instruction cache is removed.	     (In a multiprocessor system, the effect is more complex.)	     Most of the PLT shouldn't be in the instruction cache, but	     there may be a little overlap at the start and the end.	     Assumes that dcbst and icbi apply to lines of 16 bytes or	     more.  Current known line sizes are 16, 32, and 128 bytes.  */	  for (p = (char *) plt; p < (char *) &plt[offset]; p += 16)	    PPC_DCBST (p);	  PPC_SYNC;	}    }  return lazy;}/* Change the PLT entry whose reloc is 'reloc' to call the actual   routine.  */static inline Elf64_Addr __attribute__ ((always_inline))elf_machine_fixup_plt (struct link_map *map, lookup_t sym_map,		       const Elf64_Rela *reloc,		       Elf64_Addr *reloc_addr, Elf64_Addr finaladdr){  Elf64_FuncDesc *plt = (Elf64_FuncDesc *) reloc_addr;  Elf64_FuncDesc *rel = (Elf64_FuncDesc *) finaladdr;  Elf64_Addr offset = 0;  /* If sym_map is NULL, it's a weak undefined sym;  Leave the plt zero.  */  if (sym_map == NULL)