#include <limits.h>
#include <sys/mman.h>
#include <string.h>
+#include <stddef.h>
#include "pthread_impl.h"
#include "libc.h"
#include "atomic.h"
#include "syscall.h"
-#ifndef SHARED
+volatile int __thread_list_lock;
-struct tls_image {
- void *image;
- size_t len, size, align;
-} __static_tls ATTR_LIBC_VISIBILITY;
+int __init_tp(void *p)
+{
+ pthread_t td = p;
+ td->self = td;
+ int r = __set_thread_area(TP_ADJ(p));
+ if (r < 0) return -1;
+ if (!r) libc.can_do_threads = 1;
+ td->detach_state = DT_JOINABLE;
+ td->tid = __syscall(SYS_set_tid_address, &__thread_list_lock);
+ td->locale = &libc.global_locale;
+ td->robust_list.head = &td->robust_list.head;
+ td->next = td->prev = td;
+ return 0;
+}
-#define T __static_tls
+static struct builtin_tls {
+ char c;
+ struct pthread pt;
+ void *space[16];
+} builtin_tls[1];
+#define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
+
+static struct tls_module main_tls;
void *__copy_tls(unsigned char *mem)
{
pthread_t td;
- if (!T.image) return mem;
- void **dtv = (void *)mem;
- dtv[0] = (void *)1;
+ struct tls_module *p;
+ size_t i;
+ uintptr_t *dtv;
+
#ifdef TLS_ABOVE_TP
- mem += sizeof(void *) * 2;
- mem += -((uintptr_t)mem + sizeof(struct pthread)) & (T.align-1);
+ dtv = (uintptr_t*)(mem + libc.tls_size) - (libc.tls_cnt + 1);
+
+ mem += -((uintptr_t)mem + sizeof(struct pthread)) & (libc.tls_align-1);
td = (pthread_t)mem;
mem += sizeof(struct pthread);
+
+ for (i=1, p=libc.tls_head; p; i++, p=p->next) {
+ dtv[i] = (uintptr_t)(mem + p->offset) + DTP_OFFSET;
+ memcpy(mem + p->offset, p->image, p->len);
+ }
#else
+ dtv = (uintptr_t *)mem;
+
mem += libc.tls_size - sizeof(struct pthread);
- mem -= (uintptr_t)mem & (T.align-1);
+ mem -= (uintptr_t)mem & (libc.tls_align-1);
td = (pthread_t)mem;
- mem -= T.size;
+
+ for (i=1, p=libc.tls_head; p; i++, p=p->next) {
+ dtv[i] = (uintptr_t)(mem - p->offset) + DTP_OFFSET;
+ memcpy(mem - p->offset, p->image, p->len);
+ }
#endif
- td->dtv = dtv;
- dtv[1] = mem;
- memcpy(mem, T.image, T.len);
+ dtv[0] = libc.tls_cnt;
+ td->dtv = td->dtv_copy = dtv;
return td;
}
-void *__tls_get_addr(size_t *v)
-{
- return (char *)__pthread_self()->dtv[1]+v[1];
-}
-
-static void *simple(void *p)
-{
- *(void **)p = p;
- return __set_thread_area(TP_ADJ(p)) ? 0 : p;
-}
-
-weak_alias(simple, __install_initial_tls);
-
-void *__mmap(void *, size_t, int, int, int, off_t);
-
#if ULONG_MAX == 0xffffffff
typedef Elf32_Phdr Phdr;
#else
typedef Elf64_Phdr Phdr;
#endif
-void __init_tls(size_t *aux)
+extern weak hidden const size_t _DYNAMIC[];
+
+static void static_init_tls(size_t *aux)
{
- unsigned char *p, *mem;
+ unsigned char *p;
size_t n;
Phdr *phdr, *tls_phdr=0;
size_t base = 0;
-
- libc.tls_size = sizeof(struct pthread);
+ void *mem;
for (p=(void *)aux[AT_PHDR],n=aux[AT_PHNUM]; n; n--,p+=aux[AT_PHENT]) {
phdr = (void *)p;
if (phdr->p_type == PT_PHDR)
base = aux[AT_PHDR] - phdr->p_vaddr;
+ if (phdr->p_type == PT_DYNAMIC && _DYNAMIC)
+ base = (size_t)_DYNAMIC - phdr->p_vaddr;
if (phdr->p_type == PT_TLS)
tls_phdr = phdr;
+ if (phdr->p_type == PT_GNU_STACK &&
+ phdr->p_memsz > __default_stacksize)
+ __default_stacksize =
+ phdr->p_memsz < DEFAULT_STACK_MAX ?
+ phdr->p_memsz : DEFAULT_STACK_MAX;
}
- if (!tls_phdr) return;
- T.image = (void *)(base + tls_phdr->p_vaddr);
- T.len = tls_phdr->p_filesz;
- T.size = tls_phdr->p_memsz;
- T.align = tls_phdr->p_align;
+ if (tls_phdr) {
+ main_tls.image = (void *)(base + tls_phdr->p_vaddr);
+ main_tls.len = tls_phdr->p_filesz;
+ main_tls.size = tls_phdr->p_memsz;
+ main_tls.align = tls_phdr->p_align;
+ libc.tls_cnt = 1;
+ libc.tls_head = &main_tls;
+ }
- T.size += (-T.size - (uintptr_t)T.image) & (T.align-1);
- if (T.align < 4*sizeof(size_t)) T.align = 4*sizeof(size_t);
+ main_tls.size += (-main_tls.size - (uintptr_t)main_tls.image)
+ & (main_tls.align-1);
+#ifdef TLS_ABOVE_TP
+ main_tls.offset = GAP_ABOVE_TP;
+ main_tls.offset += -GAP_ABOVE_TP & (main_tls.align-1);
+#else
+ main_tls.offset = main_tls.size;
+#endif
+ if (main_tls.align < MIN_TLS_ALIGN) main_tls.align = MIN_TLS_ALIGN;
- libc.tls_size = 2*sizeof(void *)+T.size+T.align+sizeof(struct pthread);
+ libc.tls_align = main_tls.align;
+ libc.tls_size = 2*sizeof(void *) + sizeof(struct pthread)
+#ifdef TLS_ABOVE_TP
+ + main_tls.offset
+#endif
+ + main_tls.size + main_tls.align
+ + MIN_TLS_ALIGN-1 & -MIN_TLS_ALIGN;
- mem = (void *)__syscall(
-#ifdef SYS_mmap2
- SYS_mmap2,
-#else
- SYS_mmap,
+ if (libc.tls_size > sizeof builtin_tls) {
+#ifndef SYS_mmap2
+#define SYS_mmap2 SYS_mmap
#endif
- 0, libc.tls_size, PROT_READ|PROT_WRITE,
- MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ mem = (void *)__syscall(
+ SYS_mmap2,
+ 0, libc.tls_size, PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ /* -4095...-1 cast to void * will crash on dereference anyway,
+ * so don't bloat the init code checking for error codes and
+ * explicitly calling a_crash(). */
+ } else {
+ mem = builtin_tls;
+ }
- if (!__install_initial_tls(__copy_tls(mem))) a_crash();
+ /* Failure to initialize thread pointer is always fatal. */
+ if (__init_tp(__copy_tls(mem)) < 0)
+ a_crash();
}
-#else
-void __init_tls(size_t *auxv) { }
-#endif
+
+weak_alias(static_init_tls, __init_tls);
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