1 /* Initialization code for TLS in statically linked application.
2 Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
25 #include <sys/param.h>
32 #include <l4/re/dataspace>
33 #include <l4/re/mem_alloc>
37 #error makefile bug, this file is for static only
41 extern ElfW(Phdr) *_dl_phdr;
42 extern size_t _dl_phnum;
45 __attribute__ ((weak))
46 void *__libc_alloc_initial_tls(unsigned long size) __THROW;
48 static dtv_t static_dtv[2 + TLS_SLOTINFO_SURPLUS];
53 struct dtv_slotinfo_list si;
54 /* The dtv_slotinfo_list data structure does not include the actual
55 information since it is defined as an array of size zero. We define
56 here the necessary entries. Note that it is not important whether
57 there is padding or not since we will always access the information
58 through the 'si' element. */
59 dtv_slotinfo_list::dtv_slotinfo info[2 + TLS_SLOTINFO_SURPLUS];
62 /* Fake link map for the application. */
63 static struct link_map static_map;
66 /* Highest dtv index currently needed. */
67 size_t _dl_tls_max_dtv_idx;
68 /* Flag signalling whether there are gaps in the module ID allocation. */
69 bool _dl_tls_dtv_gaps;
70 /* Information about the dtv slots. */
71 struct dtv_slotinfo_list *_dl_tls_dtv_slotinfo_list;
72 /* Number of modules in the static TLS block. */
73 size_t _dl_tls_static_nelem;
74 /* Size of the static TLS block. */
75 size_t _dl_tls_static_size __attribute__((weak)) = TLS_TCB_SIZE;
76 /* Size actually allocated in the static TLS block. */
77 size_t _dl_tls_static_used;
78 /* Alignment requirement of the static TLS block. */
79 size_t _dl_tls_static_align;
81 /* Generation counter for the dtv. */
82 size_t _dl_tls_generation;
85 /* Additional definitions needed by TLS initialization. */
86 #ifdef TLS_INIT_HELPER
93 /* Create the slotinfo list. */
94 static_slotinfo.si.len = (((char *) (&static_slotinfo + 1)
95 - (char *) &static_slotinfo.si.slotinfo[0])
96 / sizeof static_slotinfo.si.slotinfo[0]);
97 // static_slotinfo.si.next = NULL; already zero
99 /* The slotinfo list. Will be extended by the code doing dynamic
101 GL(dl_tls_max_dtv_idx) = 1;
102 GL(dl_tls_dtv_slotinfo_list) = &static_slotinfo.si;
106 init_static_tls (size_t memsz, size_t align)
108 /* That is the size of the TLS memory for this object. The initialized
109 value of _dl_tls_static_size is provided by dl-open.c to request some
110 surplus that permits dynamic loading of modules with IE-model TLS. */
111 GL(dl_tls_static_size) = roundup (memsz + GL(dl_tls_static_size),
113 GL(dl_tls_static_used) = memsz;
114 /* The alignment requirement for the static TLS block. */
115 GL(dl_tls_static_align) = align;
116 /* Number of elements in the static TLS block. */
117 GL(dl_tls_static_nelem) = GL(dl_tls_max_dtv_idx);
120 __attribute__ ((weak))
121 void *__libc_alloc_initial_tls(unsigned long size) __THROW
124 using namespace L4Re;
125 Cap<Dataspace> ds(Env::env()->first_free_cap() << L4_CAP_SHIFT);
126 ::l4re_global_env->first_free_cap += 1;
127 if (Env::env()->mem_alloc()->alloc(size, ds, 0) < 0)
131 if(Env::env()->rm()->attach(&addr, size, Rm::Search_addr, ds, 0, 0) < 0)
138 __libc_setup_tls (size_t tcbsize, size_t tcbalign)
143 void *initimage = NULL;
145 size_t max_align = tcbalign;
148 /* Look through the TLS segment if there is any. */
149 if (_dl_phdr != NULL)
150 for (phdr = _dl_phdr; phdr < &_dl_phdr[_dl_phnum]; ++phdr)
151 if (phdr->p_type == PT_TLS)
153 /* Remember the values we need. */
154 memsz = phdr->p_memsz;
155 filesz = phdr->p_filesz;
156 initimage = (void *) phdr->p_vaddr;
157 align = phdr->p_align;
158 if (phdr->p_align > max_align)
159 max_align = phdr->p_align;
162 /* We have to set up the TCB block which also (possibly) contains
163 'errno'. Therefore we avoid 'malloc' which might touch 'errno'.
164 Instead we use 'sbrk' which would only uses 'errno' if it fails.
165 In this case we are right away out of memory and the user gets
166 what she/he deserves.
168 The initialized value of _dl_tls_static_size is provided by dl-open.c
169 to request some surplus that permits dynamic loading of modules with
171 # if defined(TLS_TCB_AT_TP)
172 tcb_offset = roundup (memsz + GL(dl_tls_static_size), tcbalign);
173 tlsblock = __libc_alloc_initial_tls(tcb_offset + tcbsize + max_align);
174 # elif defined(TLS_DTV_AT_TP)
175 tcb_offset = roundup (tcbsize, align ?: 1);
176 tlsblock = __libc_alloc_initial_tls(tcb_offset + memsz + max_align
177 + TLS_PRE_TCB_SIZE + GL(dl_tls_static_size));
178 //tlsblock += TLS_PRE_TCB_SIZE;
179 tlsblock = (char *)tlsblock + TLS_PRE_TCB_SIZE;
181 /* In case a model with a different layout for the TCB and DTV
182 is defined add another #elif here and in the following #ifs. */
183 # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
186 /* Align the TLS block. */
187 tlsblock = (void *) (((uintptr_t) tlsblock + max_align - 1)
190 /* Initialize the dtv. [0] is the length, [1] the generation counter. */
191 static_dtv[0].counter = (sizeof (static_dtv) / sizeof (static_dtv[0])) - 2;
192 // static_dtv[1].counter = 0; would be needed if not already done
194 /* Initialize the TLS block. */
195 # if defined(TLS_TCB_AT_TP)
196 static_dtv[2].pointer.val = ((char *) tlsblock + tcb_offset
197 - roundup (memsz, align ?: 1));
198 static_map.l_tls_offset = roundup (memsz, align ?: 1);
199 # elif defined(TLS_DTV_AT_TP)
200 static_dtv[2].pointer.val = (char *) tlsblock + tcb_offset;
201 static_map.l_tls_offset = tcb_offset;
203 # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
205 static_dtv[2].pointer.is_static = true;
206 /* sbrk gives us zero'd memory, so we don't need to clear the remainder. */
207 memcpy (static_dtv[2].pointer.val, initimage, filesz);
209 /* Install the pointer to the dtv. */
211 /* Initialize the thread pointer. */
212 # if defined(TLS_TCB_AT_TP)
213 INSTALL_DTV ((char *) tlsblock + tcb_offset, static_dtv);
214 const char *lossage = TLS_INIT_TP ((char *) tlsblock + tcb_offset, 0);
215 # elif defined(TLS_DTV_AT_TP)
216 INSTALL_DTV (tlsblock, static_dtv);
217 const char *lossage = (char *)TLS_INIT_TP (tlsblock, 0);
219 # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
221 if (__builtin_expect (lossage != NULL, 0))
224 /* We have to create a fake link map which normally would be created
225 by the dynamic linker. It just has to have enough information to
226 make the TLS routines happy. */
227 static_map.l_tls_align = align;
228 static_map.l_tls_blocksize = memsz;
229 static_map.l_tls_initimage = initimage;
230 static_map.l_tls_initimage_size = filesz;
231 static_map.l_tls_modid = 1;
234 // static_slotinfo.si.slotinfo[1].gen = 0; already zero
235 static_slotinfo.si.slotinfo[1].map = &static_map;
237 memsz = roundup (memsz, align ?: 1);
239 # if defined(TLS_TCB_AT_TP)
241 # elif defined(TLS_DTV_AT_TP)
245 init_static_tls (memsz, MAX (TLS_TCB_ALIGN, max_align));
248 /* This is called only when the data structure setup was skipped at startup,
249 when there was no need for it then. Now we have dynamically loaded
250 something needing TLS, or libpthread needs it. */
257 # if defined(TLS_TCB_AT_TP)
267 /* This is the minimal initialization function used when libpthread is
271 __attribute__ ((weak))
272 __pthread_initialize_minimal (void)
274 __libc_setup_tls (TLS_INIT_TCB_SIZE, TLS_INIT_TCB_ALIGN);
277 #elif defined NONTLS_INIT_TP
279 /* This is the minimal initialization function used when libpthread is
283 __attribute__ ((weak))
284 __pthread_initialize_minimal (void)