30  * Define stubs for TLS internals so that programs and libraries can
68 void _rtld_free_tls(void *tls, size_t tcbsize, size_t tcbalign);
70 void __libc_free_tls(void *tls, size_t tcbsize, size_t tcbalign);
141  * There are two versions of variant I of TLS
144  *   where TP points to start of TCB followed by aligned TLS segment.
145  *   Both TCB and TLS must be aligned to alignment of TLS section. The TCB[0]
147  *   Note: for Local Exec TLS Model, the offsets from TP (TCB in this case) to
148  *   TLS variables are computed by linker, so we cannot overalign TLS section.
151  *   where TP points (with bias) to TLS and TCB immediately precedes TLS without
152  *   any alignment gap[4]. Only TLS should be aligned.  The TCB[0] points to DTV
158  *     www.akkadia.org/drepper/tls.pdf
174  * Return pointer to allocated TLS block
196  * Free Static TLS using the Variant I method. The tcbsize
211  * Allocate Static TLS using the Variant I method.
214  * TLS block:
218  * | pre gap  | extended TCB |     TCB      | post gap  |    TLS segment   |
224  *  post_size is used to adjust TCB to TLS alignment for first version of TLS
227  *            TLS alignment for second version.
235 	char *tls_block, *tls;  in __libc_allocate_tls()  local
256 	/* Allocate whole TLS block */  in __libc_allocate_tls()
264 	tls = (char *)tcb + TLS_TCB_SIZE + post_size;  in __libc_allocate_tls()
273 		dtv->dtv_slots[0].dtvs_tls = tls;  in __libc_allocate_tls()
285 		dtv->dtv_slots[0].dtvs_tls = tls;  in __libc_allocate_tls()
288 			memcpy(tls, libc_tls_init, libc_tls_init_size);  in __libc_allocate_tls()
299  * Free Static TLS using the Variant II method.
309 	 * Figure out the size of the initial TLS block so that we can  in __libc_free_tls()
323  * Allocate Static TLS using the Variant II method.
329 	char *tls_block, *tls;  in __libc_allocate_tls()  local
352 	tls = (char *)tcb - libc_tls_static_space;  in __libc_allocate_tls()
358 	dtv->dtv_slots[0].dtvs_tls = tls;  in __libc_allocate_tls()
362 		 * Copy the static TLS block over whole.  in __libc_allocate_tls()
364 		memcpy(tls, (const char *)oldtcb - libc_tls_static_space,  in __libc_allocate_tls()
374 		memcpy(tls, libc_tls_init, libc_tls_init_size);  in __libc_allocate_tls()
375 		memset(tls + libc_tls_init_size, 0,  in __libc_allocate_tls()
410 	void *tls;  in _init_tls()  local
446 	tls = _rtld_allocate_tls(NULL, TLS_TCB_SIZE, TLS_TCB_ALIGN);  in _init_tls()
448 	_tcb_set(tls);  in _init_tls()