diff options
Diffstat (limited to '')
| -rw-r--r-- | libc-top-half/musl/src/env/__init_tls.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/env/__init_tls.c b/libc-top-half/musl/src/env/__init_tls.c new file mode 100644 index 0000000..ee785bc --- /dev/null +++ b/libc-top-half/musl/src/env/__init_tls.c @@ -0,0 +1,186 @@ +#ifdef __wasilibc_unmodified_upstream +#define SYSCALL_NO_TLS 1 +#include <elf.h> +#endif +#include <limits.h> +#ifdef __wasilibc_unmodified_upstream +#include <sys/mman.h> +#endif +#include <string.h> +#include <stddef.h> +#include "pthread_impl.h" +#include "libc.h" +#include "atomic.h" +#include "syscall.h" + +volatile int __thread_list_lock; + +#ifndef __wasilibc_unmodified_upstream +void __wasi_init_tp() { + __init_tp((void *)__get_tp()); +} +#endif + +int __init_tp(void *p) +{ + pthread_t td = p; + td->self = td; +#ifdef __wasilibc_unmodified_upstream + 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); +#endif + td->locale = &libc.global_locale; + td->robust_list.head = &td->robust_list.head; + td->sysinfo = __sysinfo; + td->next = td->prev = td; + return 0; +} + +#ifdef __wasilibc_unmodified_upstream + +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; +#endif + +#ifndef __wasilibc_unmodified_upstream +extern void __wasm_init_tls(void*); +#endif + +void *__copy_tls(unsigned char *mem) +{ +#ifdef __wasilibc_unmodified_upstream + pthread_t td; + struct tls_module *p; + size_t i; + uintptr_t *dtv; + +#ifdef TLS_ABOVE_TP + 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 & (libc.tls_align-1); + td = (pthread_t)mem; + + 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 + dtv[0] = libc.tls_cnt; + td->dtv = dtv; + return td; +#else + size_t tls_align = __builtin_wasm_tls_align(); + volatile void* tls_base = __builtin_wasm_tls_base(); + mem += tls_align; + mem -= (uintptr_t)mem & (tls_align-1); + __wasm_init_tls(mem); + __asm__("local.get %0\n" + "global.set __tls_base\n" + :: "r"(tls_base)); + return mem; +#endif +} + +#ifdef __wasilibc_unmodified_upstream +#if ULONG_MAX == 0xffffffff +typedef Elf32_Phdr Phdr; +#else +typedef Elf64_Phdr Phdr; +#endif + +extern weak hidden const size_t _DYNAMIC[]; + +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_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) { + 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); +#ifdef TLS_ABOVE_TP + main_tls.offset = GAP_ABOVE_TP; + main_tls.offset += (-GAP_ABOVE_TP + (uintptr_t)main_tls.image) + & (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_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; + + 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(); +} + +weak_alias(static_init_tls, __init_tls); +#endif |