void __init_tls(size_t *aux) { unsigned char *p, *mem; size_t n; Phdr *phdr, *tls_phdr=0; size_t base = 0; libc.tls_size = sizeof(struct pthread); 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_TLS) tls_phdr = phdr; } if (!tls_phdr) return; image = (void *)(base + tls_phdr->p_vaddr); len = tls_phdr->p_filesz; size = tls_phdr->p_memsz; align = tls_phdr->p_align; size += (-size - (uintptr_t)image) & (align-1); if (align < 4*sizeof(size_t)) align = 4*sizeof(size_t); libc.tls_size = 2*sizeof(void *)+size+align+sizeof(struct pthread); mem = __mmap(0, libc.tls_size, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); if (!__install_initial_tls(__copy_tls(mem))) a_crash(); }
static void static_init_tls(size_t* aux) { unsigned char* p; size_t n; Phdr *phdr, *tls_phdr = 0; size_t base = 0; 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_TLS) tls_phdr = phdr; } 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; } main_tls.size += (-main_tls.size - (uintptr_t)main_tls.image) & (main_tls.align - 1); if (main_tls.align < MIN_TLS_ALIGN) main_tls.align = MIN_TLS_ALIGN; #ifndef TLS_ABOVE_TP main_tls.offset = main_tls.size; #endif libc.tls_align = main_tls.align; libc.tls_size = 2 * sizeof(void*) + sizeof(struct pthread) + main_tls.size + main_tls.align + MIN_TLS_ALIGN - 1 & -MIN_TLS_ALIGN; if (libc.tls_size > sizeof builtin_tls) { #ifndef SYS_mmap2 #define SYS_mmap2 SYS_mmap #endif 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; } /* Failure to initialize thread pointer is always fatal. */ if (__init_tp(__copy_tls(mem)) < 0) a_crash(); }