about summary refs log tree commit diff
path: root/sysdeps/ia64/dl-fptr.c
blob: 0fb9654ab88b9c8acf96829d33a3fa677a2fae47 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
/* Unmap a loaded object.  IA-64 version.
   Copyright (C) 1999, 2000 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.  */

#include <unistd.h>
#include <string.h>
#include <sys/param.h>
#include <sys/mman.h>
#include <link.h>
#include <ldsodefs.h>
#include <elf/dynamic-link.h>
#include <dl-machine.h>
#ifdef _LIBC_REENTRANT
# include <pt-machine.h>

static int __ia64_fptr_lock = 0;
#endif

/* Because ld.so is now versioned, these functions can be in their own
   file; no relocations need to be done to call them.  Of course, if
   ld.so is not versioned...  */
#if 0
#ifndef DO_VERSIONING
# error "This will not work with versioning turned off, sorry."
#endif
#endif

#ifdef MAP_ANON
/* The fd is not examined when using MAP_ANON.  */
#define ANONFD -1
#else
extern int _dl_zerofd;
#define ANONFD _dl_zerofd
#endif


/* ld.so currently has 14 FPTR relocs, we take 256 and use them for
   the relocs for the dynamic app itself.  */
struct ia64_fptr __boot_ldso_fptr[IA64_BOOT_FPTR_SIZE];
struct ia64_fptr *__fptr_root = NULL;
struct ia64_fptr *__fptr_next = __boot_ldso_fptr;
static struct ia64_fptr *__fptr_free = NULL;
int __fptr_count = IA64_BOOT_FPTR_SIZE;

Elf64_Addr
__ia64_make_fptr (const struct link_map *sym_map, Elf64_Addr value,
		  struct ia64_fptr **root, struct ia64_fptr *mem)
{
  struct ia64_fptr **loc;
  struct ia64_fptr *f;

#ifdef _LIBC_REENTRANT
  /* Make sure we are alone. We don't need a lock during bootstrap. */
  if (mem == NULL)
    while (testandset (&__ia64_fptr_lock));
#endif

  /* Search the sorted linked list for an existing entry for this
     symbol.  */
  loc = root;
  f = *loc;
  while (f != NULL && f->func <= value)
    {
      if (f->func == value)
	goto found;
      loc = &f->next;
      f = *loc;
    }

  /* Not found.  Create a new one.  */
  if (mem != NULL)
    f = mem;
  else if (__fptr_free != NULL)
    {
      f = __fptr_free;
      __fptr_free = f->next;
    }
  else
    {
      if (__fptr_count == 0)
	{
#ifndef MAP_ANON
# define MAP_ANON 0
	  if (_dl_zerofd == -1)
	    {
	      _dl_zerofd = _dl_sysdep_open_zero_fill ();
	      if (_dl_zerofd == -1)
		{
		  __close (fd);
		  _dl_signal_error (errno, NULL,
				    "cannot open zero fill device");
		}
	    }
#endif

	  __fptr_next = __mmap (0, _dl_pagesize, PROT_READ | PROT_WRITE,
				MAP_ANON | MAP_PRIVATE, ANONFD, 0);
	  if (__fptr_next == MAP_FAILED)
	    _dl_signal_error(errno, NULL, "cannot map page for fptr");
	  __fptr_count = _dl_pagesize / sizeof (struct ia64_fptr);
	}
      f = __fptr_next++;
      __fptr_count--;
    }

  f->func = value;
  /* GOT has already been relocated in elf_get_dynamic_info - don't
     try to relocate it again.  */
  f->gp = sym_map->l_info[DT_PLTGOT]->d_un.d_ptr;
  f->next = *loc;
  *loc = f;

found:
#ifdef _LIBC_REENTRANT
  /* Release the lock.  */
  if (mem == NULL)
    __ia64_fptr_lock = 0;
#endif

  return (Elf64_Addr) f;
}

void
_dl_unmap (struct link_map *map)
{
  struct ia64_fptr **floc;
  struct ia64_fptr *f;
  struct ia64_fptr **lloc;
  struct ia64_fptr *l;

  __munmap ((void *) map->l_map_start, map->l_map_end - map->l_map_start);

#ifdef _LIBC_REENTRANT
  /* Make sure we are alone.  */
  while (testandset (&__ia64_fptr_lock));
#endif

  /* Search the sorted linked list for the first entry for this object.  */
  floc = &__fptr_root;
  f = *floc;
  while (f != NULL && f->func < map->l_map_start)
    {
      floc = &f->next;
      f = *floc;
    }

  /* We found one.  */
  if (f != NULL && f->func < map->l_map_end)
    {
      /* Get the last entry.  */
      lloc = floc;
      l = f;
      while (l && l->func < map->l_map_end)
	{
	  lloc = &l->next;
	  l = *lloc;
	}

      /* Updated FPTR.  */
      *floc = l;

      /* Prepend them to the free list.  */
      *lloc = __fptr_free;
      __fptr_free = f;
    }

#ifdef _LIBC_REENTRANT
  /* Release the lock.   */
  __ia64_fptr_lock = 0;
#endif
}