• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 #define SYSCALL_NO_TLS 1
2 #include <elf.h>
3 #include <limits.h>
4 #include <sys/mman.h>
5 #include <string.h>
6 #include <stddef.h>
7 #include "pthread_impl.h"
8 #include "libc.h"
9 #include "atomic.h"
10 #include "syscall.h"
11 #ifdef __LITEOS_A__
12 #include "stdio_impl.h"
13 #include "lock.h"
14 
15 static void *dummy_tsd[1] = { 0 };
16 weak_alias(dummy_tsd, __pthread_tsd_main);
17 static FILE *volatile dummy_file = 0;
18 weak_alias(dummy_file, __stdin_used);
19 weak_alias(dummy_file, __stdout_used);
20 weak_alias(dummy_file, __stderr_used);
21 
dummy_0()22 static void dummy_0()
23 {
24 }
25 weak_alias(dummy_0, __membarrier_init);
26 
init_file_lock(FILE * f)27 static void init_file_lock(FILE *f)
28 {
29 	if (f && f->lock<0) f->lock = 0;
30 }
31 #endif
32 volatile int __thread_list_lock;
33 
__init_tp(void * p)34 int __init_tp(void *p)
35 {
36 	pthread_t td = p;
37 	td->self = td;
38 	int r = __set_thread_area(TP_ADJ(p));
39 	if (r < 0) return -1;
40 	if (!r) libc.can_do_threads = 1;
41 	td->detach_state = DT_JOINABLE;
42 	td->tid = td->pid = __syscall(SYS_set_tid_address, &__thread_list_lock);
43 	td->proc_tid = -1;
44 	td->locale = &libc.global_locale;
45 	td->robust_list.head = &td->robust_list.head;
46 	td->sysinfo = __sysinfo;
47 	td->next = td->prev = td;
48 #ifdef __LITEOS_A__
49 	libc.threaded = 0;
50 	td->tid = __syscall(SYS_gettid);
51 	td->pid = __syscall(SYS_getpid);
52 	td->tsd = (void **)__pthread_tsd_main;
53 	for (FILE *f = *__ofl_lock(); f; f = f->next)
54 		init_file_lock(f);
55 	__ofl_unlock();
56 	init_file_lock(__stdin_used);
57 	init_file_lock(__stdout_used);
58 	init_file_lock(__stderr_used);
59 	__syscall(SYS_rt_sigprocmask, SIG_UNBLOCK, SIGPT_SET, 0, _NSIG/8);
60 	libc.threaded = 1;
61 #endif
62 	return 0;
63 }
64 
65 static struct builtin_tls {
66 	char c[8];
67 	struct pthread pt;
68 	void *space[16];
69 } builtin_tls[1];
70 #define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)
71 
72 static struct tls_module main_tls;
73 
__copy_tls(unsigned char * mem)74 void *__copy_tls(unsigned char *mem)
75 {
76 	pthread_t td;
77 	struct tls_module *p;
78 	size_t i;
79 	uintptr_t *dtv;
80 
81 #ifdef TLS_ABOVE_TP
82 	dtv = (uintptr_t*)(mem + libc.tls_size) - (libc.tls_cnt + 1);
83 
84 	mem += -((uintptr_t)mem + sizeof(struct pthread)) & (libc.tls_align-1);
85 	td = (pthread_t)mem;
86 	mem += sizeof(struct pthread);
87 
88 	for (i=1, p=libc.tls_head; p; i++, p=p->next) {
89 		dtv[i] = (uintptr_t)(mem + p->offset) + DTP_OFFSET;
90 		if (p->image) {
91 			memcpy(mem + p->offset, p->image, p->len);
92 		}
93 	}
94 #else
95 	dtv = (uintptr_t *)mem;
96 
97 	mem += libc.tls_size - sizeof(struct pthread);
98 	mem -= (uintptr_t)mem & (libc.tls_align-1);
99 	td = (pthread_t)mem;
100 
101 	for (i=1, p=libc.tls_head; p; i++, p=p->next) {
102 		dtv[i] = (uintptr_t)(mem - p->offset) + DTP_OFFSET;
103 		if (p->image) {
104 			memcpy(mem - p->offset, p->image, p->len);
105 		}
106 	}
107 #endif
108 	dtv[0] = libc.tls_cnt;
109 	td->dtv = dtv;
110 	return td;
111 }
112 
113 #if ULONG_MAX == 0xffffffff
114 typedef Elf32_Phdr Phdr;
115 #else
116 typedef Elf64_Phdr Phdr;
117 #endif
118 
119 extern weak hidden const size_t _DYNAMIC[];
120 
static_init_tls(size_t * aux)121 static void static_init_tls(size_t *aux)
122 {
123 	unsigned char *p;
124 	size_t n;
125 	Phdr *phdr, *tls_phdr=0;
126 	size_t base = 0;
127 	void *mem;
128 
129 	for (p=(void *)aux[AT_PHDR],n=aux[AT_PHNUM]; n; n--,p+=aux[AT_PHENT]) {
130 		phdr = (void *)p;
131 		if (phdr->p_type == PT_PHDR)
132 			base = aux[AT_PHDR] - phdr->p_vaddr;
133 		if (phdr->p_type == PT_DYNAMIC && _DYNAMIC)
134 			base = (size_t)_DYNAMIC - phdr->p_vaddr;
135 		if (phdr->p_type == PT_TLS)
136 			tls_phdr = phdr;
137 		if (phdr->p_type == PT_GNU_STACK &&
138 		    phdr->p_memsz > __default_stacksize)
139 			__default_stacksize =
140 				phdr->p_memsz < DEFAULT_STACK_MAX ?
141 				phdr->p_memsz : DEFAULT_STACK_MAX;
142 	}
143 
144 	if (tls_phdr) {
145 		main_tls.image = (void *)(base + tls_phdr->p_vaddr);
146 		main_tls.len = tls_phdr->p_filesz;
147 		main_tls.size = tls_phdr->p_memsz;
148 		main_tls.align = tls_phdr->p_align;
149 		libc.tls_cnt = 1;
150 		libc.tls_head = &main_tls;
151 	}
152 
153 	main_tls.size += (-main_tls.size - (uintptr_t)main_tls.image)
154 		& (main_tls.align-1);
155 #ifdef TLS_ABOVE_TP
156 	main_tls.offset = GAP_ABOVE_TP;
157 	main_tls.offset += (-GAP_ABOVE_TP + (uintptr_t)main_tls.image)
158 		& (main_tls.align-1);
159 #else
160 	main_tls.offset = main_tls.size;
161 #endif
162 	if (main_tls.align < MIN_TLS_ALIGN) main_tls.align = MIN_TLS_ALIGN;
163 
164 	libc.tls_align = main_tls.align;
165 	libc.tls_size = 2*sizeof(void *) + sizeof(struct pthread)
166 #ifdef TLS_ABOVE_TP
167 		+ main_tls.offset
168 #endif
169 		+ main_tls.size + main_tls.align
170 		+ MIN_TLS_ALIGN-1 & -MIN_TLS_ALIGN;
171 
172 	if (libc.tls_size > sizeof builtin_tls) {
173 #ifndef SYS_mmap2
174 #define SYS_mmap2 SYS_mmap
175 #endif
176 		mem = (void *)__syscall(
177 			SYS_mmap2,
178 			0, libc.tls_size, PROT_READ|PROT_WRITE,
179 			MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
180 		/* -4095...-1 cast to void * will crash on dereference anyway,
181 		 * so don't bloat the init code checking for error codes and
182 		 * explicitly calling a_crash(). */
183 	} else {
184 		mem = builtin_tls;
185 	}
186 
187 	/* Failure to initialize thread pointer is always fatal. */
188 	if (__init_tp(__copy_tls(mem)) < 0)
189 		a_crash();
190 }
191 
192 weak_alias(static_init_tls, __init_tls);
193