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-rw-r--r--libc/sysdeps/linux/i386/Makefile.arch13
-rw-r--r--libc/sysdeps/linux/i386/bits/syscalls.h2
-rw-r--r--libc/sysdeps/linux/i386/bits/uClibc_arch_features.h2
-rw-r--r--libc/sysdeps/linux/i386/clone.S8
-rw-r--r--libc/sysdeps/linux/i386/sysdep.h460
-rw-r--r--libc/sysdeps/linux/i386/vfork.S10
6 files changed, 491 insertions, 4 deletions
diff --git a/libc/sysdeps/linux/i386/Makefile.arch b/libc/sysdeps/linux/i386/Makefile.arch
index 2bf2b7607..668cca742 100644
--- a/libc/sysdeps/linux/i386/Makefile.arch
+++ b/libc/sysdeps/linux/i386/Makefile.arch
@@ -5,8 +5,17 @@
# Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
#
-CSRC := brk.c sigaction.c __syscall_error.c
+CSRC := brk.c __syscall_error.c
+
+ifneq ($(UCLIBC_HAS_THREADS_NATIVE),y)
+CSRC += sigaction.c
+endif
SSRC := \
- __longjmp.S vfork.S clone.S setjmp.S bsd-setjmp.S bsd-_setjmp.S \
+ __longjmp.S setjmp.S bsd-setjmp.S bsd-_setjmp.S \
sync_file_range.S syscall.S mmap.S mmap64.S posix_fadvise64.S
+
+
+ifneq ($(UCLIBC_HAS_THREADS_NATIVE),y)
+SSRC += vfork.S clone.S
+endif
diff --git a/libc/sysdeps/linux/i386/bits/syscalls.h b/libc/sysdeps/linux/i386/bits/syscalls.h
index 0427d91cd..9184bd6c3 100644
--- a/libc/sysdeps/linux/i386/bits/syscalls.h
+++ b/libc/sysdeps/linux/i386/bits/syscalls.h
@@ -23,7 +23,7 @@
"int $0x80\n\t" \
RESTOREARGS_##nr \
: "=a" (resultvar) \
- : "i" (name) ASMFMT_##nr(args) : "memory", "cc" \
+ : "g" (name) ASMFMT_##nr(args) : "memory", "cc" \
); \
(int) resultvar; \
})
diff --git a/libc/sysdeps/linux/i386/bits/uClibc_arch_features.h b/libc/sysdeps/linux/i386/bits/uClibc_arch_features.h
index deeec03d5..536e9c155 100644
--- a/libc/sysdeps/linux/i386/bits/uClibc_arch_features.h
+++ b/libc/sysdeps/linux/i386/bits/uClibc_arch_features.h
@@ -37,7 +37,7 @@
#undef __UCLIBC_HAVE_ASM_GLOBAL_DOT_NAME__
/* define if target supports CFI pseudo ops */
-#undef __UCLIBC_HAVE_ASM_CFI_DIRECTIVES__
+#define __UCLIBC_HAVE_ASM_CFI_DIRECTIVES__
/* define if target supports IEEE signed zero floats */
#define __UCLIBC_HAVE_SIGNED_ZERO__
diff --git a/libc/sysdeps/linux/i386/clone.S b/libc/sysdeps/linux/i386/clone.S
index 14fc25ca1..a7de3fe27 100644
--- a/libc/sysdeps/linux/i386/clone.S
+++ b/libc/sysdeps/linux/i386/clone.S
@@ -79,7 +79,10 @@ clone:
movl %eax,8(%ecx)
/* Don't leak any information. */
movl $0,4(%ecx)
+#ifndef RESET_PID
movl $0,(%ecx)
+#endif
+
/* Do the system call */
pushl %ebx
@@ -90,6 +93,10 @@ clone:
movl FLAGS+12(%esp),%ebx
movl CTID+12(%esp),%edi
movl $__NR_clone,%eax
+#ifdef RESET_PID
+ /* Remember the flag value. */
+ movl %ebx, (%ecx)
+#endif
int $0x80
popl %edi
popl %esi
@@ -121,3 +128,4 @@ __error:
jmp __syscall_error
.size clone,.-clone
+weak_alias(clone, __clone)
diff --git a/libc/sysdeps/linux/i386/sysdep.h b/libc/sysdeps/linux/i386/sysdep.h
new file mode 100644
index 000000000..ff67e8a08
--- /dev/null
+++ b/libc/sysdeps/linux/i386/sysdep.h
@@ -0,0 +1,460 @@
+/* Copyright (C) 1992,1993,1995-2000,2002-2006,2007
+ Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper, <drepper@gnu.org>, August 1995.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _LINUX_I386_SYSDEP_H
+#define _LINUX_I386_SYSDEP_H 1
+
+#include <sys/syscall.h>
+#include <common/sysdep.h>
+
+#ifdef __ASSEMBLER__
+
+/* Syntactic details of assembler. */
+
+/* ELF uses byte-counts for .align, most others use log2 of count of bytes. */
+#define ALIGNARG(log2) 1<<log2
+/* For ELF we need the `.type' directive to make shared libs work right. */
+#define ASM_TYPE_DIRECTIVE(name,typearg) .type name,typearg;
+#define ASM_SIZE_DIRECTIVE(name) .size name,.-name;
+
+/* In ELF C symbols are asm symbols. */
+#undef NO_UNDERSCORES
+#define NO_UNDERSCORES
+
+/* Define an entry point visible from C.
+
+ There is currently a bug in gdb which prevents us from specifying
+ incomplete stabs information. Fake some entries here which specify
+ the current source file. */
+#define ENTRY(name) \
+ STABS_CURRENT_FILE1("") \
+ STABS_CURRENT_FILE(name) \
+ ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name); \
+ ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function) \
+ .align ALIGNARG(4); \
+ STABS_FUN(name) \
+ C_LABEL(name) \
+ cfi_startproc; \
+ CALL_MCOUNT
+
+#undef END
+#define END(name) \
+ cfi_endproc; \
+ ASM_SIZE_DIRECTIVE(name) \
+ STABS_FUN_END(name)
+
+#ifdef HAVE_CPP_ASM_DEBUGINFO
+/* Disable that goop, because we just pass -g through to the assembler
+ and it generates proper line number information directly. */
+# define STABS_CURRENT_FILE1(name)
+# define STABS_CURRENT_FILE(name)
+# define STABS_FUN(name)
+# define STABS_FUN_END(name)
+#else
+/* Remove the following two lines once the gdb bug is fixed. */
+#define STABS_CURRENT_FILE(name) \
+ STABS_CURRENT_FILE1 (#name)
+#define STABS_CURRENT_FILE1(name) \
+ 1: .stabs name,100,0,0,1b;
+/* Emit stabs definition lines. We use F(0,1) and define t(0,1) as `int',
+ the same way gcc does it. */
+#define STABS_FUN(name) STABS_FUN2(name, name##:F(0,1))
+#define STABS_FUN2(name, namestr) \
+ .stabs "int:t(0,1)=r(0,1);-2147483648;2147483647;",128,0,0,0; \
+ .stabs #namestr,36,0,0,name;
+#define STABS_FUN_END(name) \
+ 1: .stabs "",36,0,0,1b-name;
+#endif
+
+/* If compiled for profiling, call `mcount' at the start of each function. */
+#ifdef PROF
+/* The mcount code relies on a normal frame pointer being on the stack
+ to locate our caller, so push one just for its benefit. */
+#define CALL_MCOUNT \
+ pushl %ebp; cfi_adjust_cfa_offset (4); movl %esp, %ebp; \
+ cfi_def_cfa_register (ebp); call JUMPTARGET(mcount); \
+ popl %ebp; cfi_def_cfa (esp, 4);
+#else
+#define CALL_MCOUNT /* Do nothing. */
+#endif
+
+#ifdef NO_UNDERSCORES
+/* Since C identifiers are not normally prefixed with an underscore
+ on this system, the asm identifier `syscall_error' intrudes on the
+ C name space. Make sure we use an innocuous name. */
+#define syscall_error __syscall_error
+#define mcount _mcount
+#endif
+
+#undef JUMPTARGET
+#ifdef __PIC__
+#define JUMPTARGET(name) name##@PLT
+#define SYSCALL_PIC_SETUP \
+ pushl %ebx; \
+ cfi_adjust_cfa_offset (4); \
+ call 0f; \
+0: popl %ebx; \
+ cfi_adjust_cfa_offset (-4); \
+ addl $_GLOBAL_OFFSET_TABLE+[.-0b], %ebx;
+
+
+# define SETUP_PIC_REG(reg) \
+ .ifndef __x86.get_pc_thunk.reg; \
+ .section .gnu.linkonce.t.__x86.get_pc_thunk.reg,"ax",@progbits; \
+ .globl __x86.get_pc_thunk.reg; \
+ .hidden __x86.get_pc_thunk.reg; \
+ .type __x86.get_pc_thunk.reg,@function; \
+__x86.get_pc_thunk.reg: \
+ movl (%esp), %e##reg; \
+ ret; \
+ .size __x86.get_pc_thunk.reg, . - __x86.get_pc_thunk.reg; \
+ .previous; \
+ .endif; \
+ call __x86.get_pc_thunk.reg
+
+# define LOAD_PIC_REG(reg) \
+ SETUP_PIC_REG(reg); addl $_GLOBAL_OFFSET_TABLE_, %e##reg
+
+#else
+#define JUMPTARGET(name) name
+#define SYSCALL_PIC_SETUP /* Nothing. */
+#endif
+
+/* Local label name for asm code. */
+#ifndef L
+#ifdef HAVE_ELF
+#define L(name) .L##name
+#else
+#define L(name) name
+#endif
+#endif
+
+#endif /* __ASSEMBLER__ */
+
+#ifndef offsetof
+# define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#endif
+
+/* For Linux we can use the system call table in the header file
+ /usr/include/asm/unistd.h
+ of the kernel. But these symbols do not follow the SYS_* syntax
+ so we have to redefine the `SYS_ify' macro here. */
+#undef SYS_ify
+#define SYS_ify(syscall_name) __NR_##syscall_name
+
+#if defined USE_DL_SYSINFO \
+ && (!defined NOT_IN_libc || defined IS_IN_libpthread)
+# define I386_USE_SYSENTER 1
+#else
+# undef I386_USE_SYSENTER
+#endif
+
+#ifdef __ASSEMBLER__
+
+/* Linux uses a negative return value to indicate syscall errors,
+ unlike most Unices, which use the condition codes' carry flag.
+
+ Since version 2.1 the return value of a system call might be
+ negative even if the call succeeded. E.g., the `lseek' system call
+ might return a large offset. Therefore we must not anymore test
+ for < 0, but test for a real error by making sure the value in %eax
+ is a real error number. Linus said he will make sure the no syscall
+ returns a value in -1 .. -4095 as a valid result so we can savely
+ test with -4095. */
+
+/* We don't want the label for the error handle to be global when we define
+ it here. */
+#ifdef __PIC__
+# define SYSCALL_ERROR_LABEL 0f
+#else
+# define SYSCALL_ERROR_LABEL syscall_error
+#endif
+
+#undef PSEUDO
+#define PSEUDO(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args); \
+ cmpl $-4095, %eax; \
+ jae SYSCALL_ERROR_LABEL; \
+ L(pseudo_end):
+
+#undef PSEUDO_END
+#define PSEUDO_END(name) \
+ SYSCALL_ERROR_HANDLER \
+ END (name)
+
+#undef PSEUDO_NOERRNO
+#define PSEUDO_NOERRNO(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args)
+
+#undef PSEUDO_END_NOERRNO
+#define PSEUDO_END_NOERRNO(name) \
+ END (name)
+
+#define ret_NOERRNO ret
+
+/* The function has to return the error code. */
+#undef PSEUDO_ERRVAL
+#define PSEUDO_ERRVAL(name, syscall_name, args) \
+ .text; \
+ ENTRY (name) \
+ DO_CALL (syscall_name, args); \
+ negl %eax
+
+#undef PSEUDO_END_ERRVAL
+#define PSEUDO_END_ERRVAL(name) \
+ END (name)
+
+#define ret_ERRVAL ret
+
+#ifndef __PIC__
+# define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */
+#else
+
+# ifdef RTLD_PRIVATE_ERRNO
+# define SYSCALL_ERROR_HANDLER \
+0:SETUP_PIC_REG(cx); \
+ addl $_GLOBAL_OFFSET_TABLE_, %ecx; \
+ xorl %edx, %edx; \
+ subl %eax, %edx; \
+ movl %edx, rtld_errno@GOTOFF(%ecx); \
+ orl $-1, %eax; \
+ jmp L(pseudo_end);
+
+# elif defined _LIBC_REENTRANT
+
+# if USE___THREAD
+# ifndef NOT_IN_libc
+# define SYSCALL_ERROR_ERRNO __libc_errno
+# else
+# define SYSCALL_ERROR_ERRNO errno
+# endif
+# define SYSCALL_ERROR_HANDLER \
+0:SETUP_PIC_REG (cx); \
+ addl $_GLOBAL_OFFSET_TABLE_, %ecx; \
+ movl SYSCALL_ERROR_ERRNO@GOTNTPOFF(%ecx), %ecx; \
+ xorl %edx, %edx; \
+ subl %eax, %edx; \
+ SYSCALL_ERROR_HANDLER_TLS_STORE (%edx, %ecx); \
+ orl $-1, %eax; \
+ jmp L(pseudo_end);
+# ifndef NO_TLS_DIRECT_SEG_REFS
+# define SYSCALL_ERROR_HANDLER_TLS_STORE(src, destoff) \
+ movl src, %gs:(destoff)
+# else
+# define SYSCALL_ERROR_HANDLER_TLS_STORE(src, destoff) \
+ addl %gs:0, destoff; \
+ movl src, (destoff)
+# endif
+# else
+# define SYSCALL_ERROR_HANDLER \
+0:pushl %ebx; \
+ cfi_adjust_cfa_offset (4); \
+ cfi_rel_offset (ebx, 0); \
+ SETUP_PIC_REG (bx); \
+ addl $_GLOBAL_OFFSET_TABLE_, %ebx; \
+ xorl %edx, %edx; \
+ subl %eax, %edx; \
+ pushl %edx; \
+ cfi_adjust_cfa_offset (4); \
+ call __errno_location@PLT; \
+ popl %ecx; \
+ cfi_adjust_cfa_offset (-4); \
+ popl %ebx; \
+ cfi_adjust_cfa_offset (-4); \
+ cfi_restore (ebx); \
+ movl %ecx, (%eax); \
+ orl $-1, %eax; \
+ jmp L(pseudo_end);
+/* A quick note: it is assumed that the call to `__errno_location' does
+ not modify the stack! */
+# endif
+# else
+/* Store (- %eax) into errno through the GOT. */
+# define SYSCALL_ERROR_HANDLER \
+0:SETUP_PIC_REG(cx); \
+ addl $_GLOBAL_OFFSET_TABLE_, %ecx; \
+ xorl %edx, %edx; \
+ subl %eax, %edx; \
+ movl errno@GOT(%ecx), %ecx; \
+ movl %edx, (%ecx); \
+ orl $-1, %eax; \
+ jmp L(pseudo_end);
+# endif /* _LIBC_REENTRANT */
+#endif /* __PIC__ */
+
+
+/* The original calling convention for system calls on Linux/i386 is
+ to use int $0x80. */
+#ifdef I386_USE_SYSENTER
+# ifdef SHARED
+# define ENTER_KERNEL call *%gs:SYSINFO_OFFSET
+# else
+# define ENTER_KERNEL call *_dl_sysinfo
+# endif
+#else
+# define ENTER_KERNEL int $0x80
+#endif
+
+/* Linux takes system call arguments in registers:
+
+ syscall number %eax call-clobbered
+ arg 1 %ebx call-saved
+ arg 2 %ecx call-clobbered
+ arg 3 %edx call-clobbered
+ arg 4 %esi call-saved
+ arg 5 %edi call-saved
+ arg 6 %ebp call-saved
+
+ The stack layout upon entering the function is:
+
+ 24(%esp) Arg# 6
+ 20(%esp) Arg# 5
+ 16(%esp) Arg# 4
+ 12(%esp) Arg# 3
+ 8(%esp) Arg# 2
+ 4(%esp) Arg# 1
+ (%esp) Return address
+
+ (Of course a function with say 3 arguments does not have entries for
+ arguments 4, 5, and 6.)
+
+ The following code tries hard to be optimal. A general assumption
+ (which is true according to the data books I have) is that
+
+ 2 * xchg is more expensive than pushl + movl + popl
+
+ Beside this a neat trick is used. The calling conventions for Linux
+ tell that among the registers used for parameters %ecx and %edx need
+ not be saved. Beside this we may clobber this registers even when
+ they are not used for parameter passing.
+
+ As a result one can see below that we save the content of the %ebx
+ register in the %edx register when we have less than 3 arguments
+ (2 * movl is less expensive than pushl + popl).
+
+ Second unlike for the other registers we don't save the content of
+ %ecx and %edx when we have more than 1 and 2 registers resp.
+
+ The code below might look a bit long but we have to take care for
+ the pipelined processors (i586). Here the `pushl' and `popl'
+ instructions are marked as NP (not pairable) but the exception is
+ two consecutive of these instruction. This gives no penalty on
+ other processors though. */
+
+#undef DO_CALL
+#define DO_CALL(syscall_name, args) \
+ PUSHARGS_##args \
+ DOARGS_##args \
+ movl $SYS_ify (syscall_name), %eax; \
+ ENTER_KERNEL \
+ POPARGS_##args
+
+#define PUSHARGS_0 /* No arguments to push. */
+#define DOARGS_0 /* No arguments to frob. */
+#define POPARGS_0 /* No arguments to pop. */
+#define _PUSHARGS_0 /* No arguments to push. */
+#define _DOARGS_0(n) /* No arguments to frob. */
+#define _POPARGS_0 /* No arguments to pop. */
+
+#define PUSHARGS_1 movl %ebx, %edx; L(SAVEBX1): PUSHARGS_0
+#define DOARGS_1 _DOARGS_1 (4)
+#define POPARGS_1 POPARGS_0; movl %edx, %ebx; L(RESTBX1):
+#define _PUSHARGS_1 pushl %ebx; cfi_adjust_cfa_offset (4); \
+ cfi_rel_offset (ebx, 0); L(PUSHBX1): _PUSHARGS_0
+#define _DOARGS_1(n) movl n(%esp), %ebx; _DOARGS_0(n-4)
+#define _POPARGS_1 _POPARGS_0; popl %ebx; cfi_adjust_cfa_offset (-4); \
+ cfi_restore (ebx); L(POPBX1):
+
+#define PUSHARGS_2 PUSHARGS_1
+#define DOARGS_2 _DOARGS_2 (8)
+#define POPARGS_2 POPARGS_1
+#define _PUSHARGS_2 _PUSHARGS_1
+#define _DOARGS_2(n) movl n(%esp), %ecx; _DOARGS_1 (n-4)
+#define _POPARGS_2 _POPARGS_1
+
+#define PUSHARGS_3 _PUSHARGS_2
+#define DOARGS_3 _DOARGS_3 (16)
+#define POPARGS_3 _POPARGS_3
+#define _PUSHARGS_3 _PUSHARGS_2
+#define _DOARGS_3(n) movl n(%esp), %edx; _DOARGS_2 (n-4)
+#define _POPARGS_3 _POPARGS_2
+
+#define PUSHARGS_4 _PUSHARGS_4
+#define DOARGS_4 _DOARGS_4 (24)
+#define POPARGS_4 _POPARGS_4
+#define _PUSHARGS_4 pushl %esi; cfi_adjust_cfa_offset (4); \
+ cfi_rel_offset (esi, 0); L(PUSHSI1): _PUSHARGS_3
+#define _DOARGS_4(n) movl n(%esp), %esi; _DOARGS_3 (n-4)
+#define _POPARGS_4 _POPARGS_3; popl %esi; cfi_adjust_cfa_offset (-4); \
+ cfi_restore (esi); L(POPSI1):
+
+#define PUSHARGS_5 _PUSHARGS_5
+#define DOARGS_5 _DOARGS_5 (32)
+#define POPARGS_5 _POPARGS_5
+#define _PUSHARGS_5 pushl %edi; cfi_adjust_cfa_offset (4); \
+ cfi_rel_offset (edi, 0); L(PUSHDI1): _PUSHARGS_4
+#define _DOARGS_5(n) movl n(%esp), %edi; _DOARGS_4 (n-4)
+#define _POPARGS_5 _POPARGS_4; popl %edi; cfi_adjust_cfa_offset (-4); \
+ cfi_restore (edi); L(POPDI1):
+
+#define PUSHARGS_6 _PUSHARGS_6
+#define DOARGS_6 _DOARGS_6 (40)
+#define POPARGS_6 _POPARGS_6
+#define _PUSHARGS_6 pushl %ebp; cfi_adjust_cfa_offset (4); \
+ cfi_rel_offset (ebp, 0); L(PUSHBP1): _PUSHARGS_5
+#define _DOARGS_6(n) movl n(%esp), %ebp; _DOARGS_5 (n-4)
+#define _POPARGS_6 _POPARGS_5; popl %ebp; cfi_adjust_cfa_offset (-4); \
+ cfi_restore (ebp); L(POPBP1):
+
+#endif /* __ASSEMBLER__ */
+
+
+/* Pointer mangling support. */
+#if defined NOT_IN_libc && defined IS_IN_rtld
+/* We cannot use the thread descriptor because in ld.so we use setjmp
+ earlier than the descriptor is initialized. Using a global variable
+ is too complicated here since we have no PC-relative addressing mode. */
+#else
+# ifdef __ASSEMBLER__
+# define PTR_MANGLE(reg) xorl %gs:POINTER_GUARD, reg; \
+ roll $9, reg
+# define PTR_DEMANGLE(reg) rorl $9, reg; \
+ xorl %gs:POINTER_GUARD, reg
+# else
+# define PTR_MANGLE(var) __asm__ ("xorl %%gs:%c2, %0\n" \
+ "roll $9, %0" \
+ : "=r" (var) \
+ : "0" (var), \
+ "i" (offsetof (tcbhead_t, \
+ pointer_guard)))
+# define PTR_DEMANGLE(var) __asm__ ("rorl $9, %0\n" \
+ "xorl %%gs:%c2, %0" \
+ : "=r" (var) \
+ : "0" (var), \
+ "i" (offsetof (tcbhead_t, \
+ pointer_guard)))
+# endif
+#endif
+
+#endif /* linux/i386/sysdep.h */
diff --git a/libc/sysdeps/linux/i386/vfork.S b/libc/sysdeps/linux/i386/vfork.S
index 8005ff1d2..c9db2f48c 100644
--- a/libc/sysdeps/linux/i386/vfork.S
+++ b/libc/sysdeps/linux/i386/vfork.S
@@ -18,9 +18,19 @@
__vfork:
popl %ecx
+
+#ifdef SAVE_PID
+ SAVE_PID
+#endif
+
movl $__NR_vfork,%eax
int $0x80
pushl %ecx
+
+#ifdef RESTORE_PID
+ RESTORE_PID
+#endif
+
cmpl $-4095,%eax
jae __syscall_error
ret
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-09 17:02:10 +0000