ldso/ldso/fdpic/dl-sysdep.h

   1 /* Copyright (C) 2003, 2004 Red Hat, Inc.
   2  * Contributed by Alexandre Oliva <aoliva@redhat.com>
   3  * Copyright (C) 2006-2011 Analog Devices, Inc.
   4  * Based on ../i386/dl-sysdep.h
   5  *
   6  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
   7  */
   8
   9 #define HAVE_DL_INLINES_H
  10
  11 /*
  12  * Initialization sequence for a GOT.  Copy the resolver function
  13  * descriptor and the pointer to the elf_resolve/link_map data
  14  * structure.  Initialize the got_value in the module while at that.
  15  */
  16 #define INIT_GOT(GOT_BASE,MODULE) \
  17 {                               \
  18   (MODULE)->loadaddr.got_value = (GOT_BASE); \
  19   GOT_BASE[0] = ((unsigned long *)&_dl_linux_resolve)[0]; \
  20   GOT_BASE[1] = ((unsigned long *)&_dl_linux_resolve)[1]; \
  21   GOT_BASE[2] = (unsigned long) MODULE; \
  22 }
  23
  24 struct elf_resolve;
  25
  26 struct funcdesc_value
  27 {
  28   void *entry_point;
  29   void *got_value;
  30 } __attribute__((__aligned__(8)));
  31
  32 struct funcdesc_ht;
  33
  34 #define DL_LOADADDR_TYPE struct elf32_fdpic_loadaddr
  35
  36 #define DL_RELOC_ADDR(LOADADDR, ADDR) \
  37     ((ElfW(Addr))__reloc_pointer ((void*)(ADDR), (LOADADDR).map))
  38
  39 #define DL_ADDR_TO_FUNC_PTR(ADDR, LOADADDR) \
  40   ((void(*)(void)) _dl_funcdesc_for ((void*)(ADDR), (LOADADDR).got_value))
  41
  42 #define _dl_stabilize_funcdesc(val) \
  43   ({ __asm__ ("" : "+m" (*(val))); (val); })
  44
  45 #define DL_CALL_FUNC_AT_ADDR(ADDR, LOADADDR, SIGNATURE, ...) \
  46   ({ struct funcdesc_value fd = { (void*)(ADDR), (LOADADDR).got_value }; \
  47      void (*pf)(void) = (void*) _dl_stabilize_funcdesc (&fd); \
  48      (* SIGNATURE pf)(__VA_ARGS__); })
  49
  50 #define DL_INIT_LOADADDR_BOOT(LOADADDR, BASEADDR) \
  51   (__dl_init_loadaddr_map (&(LOADADDR), dl_boot_got_pointer, \
  52                            dl_boot_ldsomap ?: dl_boot_progmap))
  53
  54 #define DL_INIT_LOADADDR_PROG(LOADADDR, BASEADDR) \
  55   (__dl_init_loadaddr_map (&(LOADADDR), 0, dl_boot_progmap))
  56
  57 #define DL_INIT_LOADADDR_EXTRA_DECLS \
  58   int dl_init_loadaddr_load_count;
  59 #define DL_INIT_LOADADDR(LOADADDR, BASEADDR, PHDR, PHDRCNT) \
  60   (dl_init_loadaddr_load_count = \
  61      __dl_init_loadaddr (&(LOADADDR), (PHDR), (PHDRCNT)))
  62 #define DL_INIT_LOADADDR_HDR(LOADADDR, ADDR, PHDR) \
  63   (__dl_init_loadaddr_hdr ((LOADADDR), (ADDR), (PHDR), \
  64                            dl_init_loadaddr_load_count))
  65 #define DL_UPDATE_LOADADDR_HDR(LOADADDR, ADDR, PHDR) \
  66   (__dl_update_loadaddr_hdr ((LOADADDR), (ADDR), (PHDR)))
  67 #define DL_LOADADDR_UNMAP(LOADADDR, LEN) \
  68   (__dl_loadaddr_unmap ((LOADADDR), (NULL)))
  69 #define DL_LIB_UNMAP(LIB, LEN) \
  70   (__dl_loadaddr_unmap ((LIB)->loadaddr, (LIB)->funcdesc_ht))
  71 #define DL_LOADADDR_BASE(LOADADDR) \
  72   ((LOADADDR).got_value)
  73
  74 /* This is called from dladdr(), such that we map a function
  75    descriptor's address to the function's entry point before trying to
  76    find in which library it's defined.  */
  77 #define DL_LOOKUP_ADDRESS(ADDRESS) (_dl_lookup_address (ADDRESS))
  78
  79 #define DL_ADDR_IN_LOADADDR(ADDR, TPNT, TFROM) \
  80   (! (TFROM) && __dl_addr_in_loadaddr ((void*)(ADDR), (TPNT)->loadaddr))
  81
  82 /*
  83  * Compute the GOT address.  On several platforms, we use assembly
  84  * here.  on FDPIC, there's no way to compute the GOT address,
  85  * since the offset between text and data is not fixed, so we arrange
  86  * for the ldso assembly entry point to pass this value as an argument
  87  * to _dl_start.  */
  88 #define DL_BOOT_COMPUTE_GOT(got) ((got) = dl_boot_got_pointer)
  89
  90 #define DL_BOOT_COMPUTE_DYN(dpnt, got, load_addr) \
  91   ((dpnt) = dl_boot_ldso_dyn_pointer)
  92
  93 /* We want want to apply all relocations in the interpreter during
  94    bootstrap.  Because of this, we have to skip the interpreter
  95    relocations in _dl_parse_relocation_information(), see
  96    elfinterp.c.  */
  97 #define DL_SKIP_BOOTSTRAP_RELOC(SYMTAB, INDEX, STRTAB) 0
  98
  99 #if defined(__NR_pread) || defined(__NR_pread64)
 100 #define _DL_PREAD(FD, BUF, SIZE, OFFSET) \
 101   (_dl_pread((FD), (BUF), (SIZE), (OFFSET)))
 102 #endif
 103
 104 /* We want to return to dlsym() a function descriptor if the symbol
 105    turns out to be a function.  */
 106 #define DL_FIND_HASH_VALUE(TPNT, TYPE_CLASS, SYM) \
 107   (((TYPE_CLASS) & ELF_RTYPE_CLASS_DLSYM) \
 108    && ELF32_ST_TYPE((SYM)->st_info) == STT_FUNC \
 109    ? _dl_funcdesc_for ((void *)DL_RELOC_ADDR ((TPNT)->loadaddr, (SYM)->st_value), \
 110                        (TPNT)->loadaddr.got_value)                           \
 111    : DL_RELOC_ADDR ((TPNT)->loadaddr, (SYM)->st_value))
 112
 113 #define DL_GET_READY_TO_RUN_EXTRA_PARMS \
 114     , struct elf32_fdpic_loadmap *dl_boot_progmap, Elf32_Addr dl_boot_got_pointer
 115 #define DL_GET_READY_TO_RUN_EXTRA_ARGS \
 116     , dl_boot_progmap, dl_boot_got_pointer
 117
 118 /* Define this to declare the library offset. */
 119 #define DL_DEF_LIB_OFFSET
 120
 121 /* Define this to get the library offset. */
 122 #define DL_GET_LIB_OFFSET() 0
 123
 124 /* Define this to set the library offset. */
 125 #define DL_SET_LIB_OFFSET(offset)
 126
 127 /* Define this to get the real object's runtime address. */
 128 #define DL_GET_RUN_ADDR(loadaddr, mapaddr) (loadaddr)
 129
 130 #ifdef __USE_GNU
 131 # include <link.h>
 132 #else
 133 # define __USE_GNU
 134 # include <link.h>
 135 # undef __USE_GNU
 136 #endif