Commit 1d4b4b29 authored by Al Viro's avatar Al Viro

x86, um: switch to generic fork/vfork/clone

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 71613c3b
......@@ -14,25 +14,6 @@
#include <asm/uaccess.h>
#include <asm/unistd.h>
long sys_fork(void)
{
return do_fork(SIGCHLD, 0,
&current->thread.regs, 0, NULL, NULL);
}
long sys_vfork(void)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0,
&current->thread.regs, 0, NULL, NULL);
}
long sys_clone(unsigned long clone_flags, unsigned long newsp,
void __user *parent_tid, void __user *child_tid)
{
return do_fork(clone_flags, newsp, &current->thread.regs, 0, parent_tid,
child_tid);
}
long old_mmap(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags,
unsigned long fd, unsigned long offset)
......
......@@ -112,6 +112,7 @@ config X86
select GENERIC_KERNEL_EXECVE
select MODULES_USE_ELF_REL if X86_32
select MODULES_USE_ELF_RELA if X86_64
select CLONE_BACKWARDS if X86_32
config INSTRUCTION_DECODER
def_bool y
......
......@@ -467,10 +467,15 @@ GLOBAL(\label)
PTREGSCALL stub32_sigaltstack, sys32_sigaltstack, %rdx
PTREGSCALL stub32_execve, compat_sys_execve, %rcx
PTREGSCALL stub32_fork, sys_fork, %rdi
PTREGSCALL stub32_clone, sys32_clone, %rdx
PTREGSCALL stub32_vfork, sys_vfork, %rdi
PTREGSCALL stub32_iopl, sys_iopl, %rsi
ALIGN
GLOBAL(stub32_clone)
leaq sys_clone(%rip),%rax
mov %r8, %rcx
jmp ia32_ptregs_common
ALIGN
ia32_ptregs_common:
popq %r11
......
......@@ -385,17 +385,6 @@ asmlinkage long sys32_sendfile(int out_fd, int in_fd,
return ret;
}
asmlinkage long sys32_clone(unsigned int clone_flags, unsigned int newsp,
struct pt_regs *regs)
{
void __user *parent_tid = (void __user *)regs->dx;
void __user *child_tid = (void __user *)regs->di;
if (!newsp)
newsp = regs->sp;
return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
}
/*
* Some system calls that need sign extended arguments. This could be
* done by a generic wrapper.
......
......@@ -54,8 +54,6 @@ asmlinkage long sys32_pwrite(unsigned int, const char __user *, u32, u32, u32);
asmlinkage long sys32_personality(unsigned long);
asmlinkage long sys32_sendfile(int, int, compat_off_t __user *, s32);
asmlinkage long sys32_clone(unsigned int, unsigned int, struct pt_regs *);
long sys32_lseek(unsigned int, int, unsigned int);
long sys32_kill(int, int);
long sys32_fadvise64_64(int, __u32, __u32, __u32, __u32, int);
......
......@@ -21,10 +21,15 @@ asmlinkage long sys_ioperm(unsigned long, unsigned long, int);
long sys_iopl(unsigned int, struct pt_regs *);
/* kernel/process.c */
int sys_fork(struct pt_regs *);
int sys_vfork(struct pt_regs *);
long sys_clone(unsigned long, unsigned long, void __user *,
void __user *, struct pt_regs *);
asmlinkage long sys_fork(void);
asmlinkage long sys_vfork(void);
#ifdef CONFIG_CLONE_BACKWARDS
asmlinkage long sys_clone(unsigned long, unsigned long, void __user *, int,
void __user *);
#else
asmlinkage long sys_clone(unsigned long, unsigned long, void __user *,
void __user *, int);
#endif
/* kernel/ldt.c */
asmlinkage int sys_modify_ldt(int, void __user *, unsigned long);
......
......@@ -51,6 +51,9 @@
# define __ARCH_WANT_SYS_UTIME
# define __ARCH_WANT_SYS_WAITPID
# define __ARCH_WANT_SYS_EXECVE
# define __ARCH_WANT_SYS_FORK
# define __ARCH_WANT_SYS_VFORK
# define __ARCH_WANT_SYS_CLONE
/*
* "Conditional" syscalls
......
......@@ -739,30 +739,12 @@ ENTRY(ptregs_##name) ; \
ENDPROC(ptregs_##name)
PTREGSCALL1(iopl)
PTREGSCALL0(fork)
PTREGSCALL0(vfork)
PTREGSCALL2(sigaltstack)
PTREGSCALL0(sigreturn)
PTREGSCALL0(rt_sigreturn)
PTREGSCALL2(vm86)
PTREGSCALL1(vm86old)
/* Clone is an oddball. The 4th arg is in %edi */
ENTRY(ptregs_clone)
CFI_STARTPROC
leal 4(%esp),%eax
pushl_cfi %eax
pushl_cfi PT_EDI(%eax)
movl PT_EDX(%eax),%ecx
movl PT_ECX(%eax),%edx
movl PT_EBX(%eax),%eax
call sys_clone
addl $8,%esp
CFI_ADJUST_CFA_OFFSET -8
ret
CFI_ENDPROC
ENDPROC(ptregs_clone)
.macro FIXUP_ESPFIX_STACK
/*
* Switch back for ESPFIX stack to the normal zerobased stack
......
......@@ -845,9 +845,25 @@ ENTRY(\label)
END(\label)
.endm
PTREGSCALL stub_clone, sys_clone, %r8
PTREGSCALL stub_fork, sys_fork, %rdi
PTREGSCALL stub_vfork, sys_vfork, %rdi
.macro FORK_LIKE func
ENTRY(stub_\func)
CFI_STARTPROC
popq %r11 /* save return address */
PARTIAL_FRAME 0
SAVE_REST
pushq %r11 /* put it back on stack */
FIXUP_TOP_OF_STACK %r11, 8
DEFAULT_FRAME 0 8 /* offset 8: return address */
call sys_\func
RESTORE_TOP_OF_STACK %r11, 8
ret $REST_SKIP /* pop extended registers */
CFI_ENDPROC
END(stub_\func)
.endm
FORK_LIKE clone
FORK_LIKE fork
FORK_LIKE vfork
PTREGSCALL stub_sigaltstack, sys_sigaltstack, %rdx
PTREGSCALL stub_iopl, sys_iopl, %rsi
......
......@@ -262,36 +262,6 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
propagate_user_return_notify(prev_p, next_p);
}
int sys_fork(struct pt_regs *regs)
{
return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
}
/*
* This is trivial, and on the face of it looks like it
* could equally well be done in user mode.
*
* Not so, for quite unobvious reasons - register pressure.
* In user mode vfork() cannot have a stack frame, and if
* done by calling the "clone()" system call directly, you
* do not have enough call-clobbered registers to hold all
* the information you need.
*/
int sys_vfork(struct pt_regs *regs)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, 0,
NULL, NULL);
}
long
sys_clone(unsigned long clone_flags, unsigned long newsp,
void __user *parent_tid, void __user *child_tid, struct pt_regs *regs)
{
if (!newsp)
newsp = regs->sp;
return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
}
/*
* Idle related variables and functions
*/
......
......@@ -129,7 +129,7 @@ void release_thread(struct task_struct *dead_task)
int copy_thread(unsigned long clone_flags, unsigned long sp,
unsigned long arg,
struct task_struct *p, struct pt_regs *regs)
struct task_struct *p, struct pt_regs *unused)
{
struct pt_regs *childregs = task_pt_regs(p);
struct task_struct *tsk;
......@@ -138,7 +138,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
p->thread.sp = (unsigned long) childregs;
p->thread.sp0 = (unsigned long) (childregs+1);
if (unlikely(!regs)) {
if (unlikely(p->flags & PF_KTHREAD)) {
/* kernel thread */
memset(childregs, 0, sizeof(struct pt_regs));
p->thread.ip = (unsigned long) ret_from_kernel_thread;
......@@ -156,12 +156,13 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
return 0;
}
*childregs = *regs;
*childregs = *current_pt_regs();
childregs->ax = 0;
childregs->sp = sp;
if (sp)
childregs->sp = sp;
p->thread.ip = (unsigned long) ret_from_fork;
task_user_gs(p) = get_user_gs(regs);
task_user_gs(p) = get_user_gs(current_pt_regs());
p->fpu_counter = 0;
p->thread.io_bitmap_ptr = NULL;
......
......@@ -169,7 +169,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
savesegment(ds, p->thread.ds);
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
if (unlikely(!regs)) {
if (unlikely(p->flags & PF_KTHREAD)) {
/* kernel thread */
memset(childregs, 0, sizeof(struct pt_regs));
childregs->sp = (unsigned long)childregs;
......@@ -181,10 +181,11 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
childregs->flags = X86_EFLAGS_IF | X86_EFLAGS_BIT1;
return 0;
}
*childregs = *regs;
*childregs = *current_pt_regs();
childregs->ax = 0;
childregs->sp = sp;
if (sp)
childregs->sp = sp;
err = -ENOMEM;
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
......
......@@ -8,7 +8,7 @@
#
0 i386 restart_syscall sys_restart_syscall
1 i386 exit sys_exit
2 i386 fork ptregs_fork stub32_fork
2 i386 fork sys_fork stub32_fork
3 i386 read sys_read
4 i386 write sys_write
5 i386 open sys_open compat_sys_open
......@@ -126,7 +126,7 @@
117 i386 ipc sys_ipc sys32_ipc
118 i386 fsync sys_fsync
119 i386 sigreturn ptregs_sigreturn stub32_sigreturn
120 i386 clone ptregs_clone stub32_clone
120 i386 clone sys_clone stub32_clone
121 i386 setdomainname sys_setdomainname
122 i386 uname sys_newuname
123 i386 modify_ldt sys_modify_ldt
......@@ -196,7 +196,7 @@
187 i386 sendfile sys_sendfile sys32_sendfile
188 i386 getpmsg
189 i386 putpmsg
190 i386 vfork ptregs_vfork stub32_vfork
190 i386 vfork sys_vfork stub32_vfork
191 i386 ugetrlimit sys_getrlimit compat_sys_getrlimit
192 i386 mmap2 sys_mmap_pgoff
193 i386 truncate64 sys_truncate64 sys32_truncate64
......
......@@ -25,6 +25,7 @@ config X86_32
select HAVE_AOUT
select ARCH_WANT_IPC_PARSE_VERSION
select MODULES_USE_ELF_REL
select CLONE_BACKWARDS
config X86_64
def_bool 64BIT
......
......@@ -24,13 +24,10 @@
#define old_mmap sys_old_mmap
#define ptregs_fork sys_fork
#define ptregs_iopl sys_iopl
#define ptregs_vm86old sys_vm86old
#define ptregs_clone i386_clone
#define ptregs_vm86 sys_vm86
#define ptregs_sigaltstack sys_sigaltstack
#define ptregs_vfork sys_vfork
#define __SYSCALL_I386(nr, sym, compat) extern asmlinkage void sym(void) ;
#include <asm/syscalls_32.h>
......
......@@ -6,21 +6,6 @@
#include <linux/syscalls.h>
#include <sysdep/syscalls.h>
/*
* The prototype on i386 is:
*
* int clone(int flags, void * child_stack, int * parent_tidptr, struct user_desc * newtls
*
* and the "newtls" arg. on i386 is read by copy_thread directly from the
* register saved on the stack.
*/
long i386_clone(unsigned long clone_flags, unsigned long newsp,
int __user *parent_tid, void *newtls, int __user *child_tid)
{
return sys_clone(clone_flags, newsp, parent_tid, child_tid);
}
long sys_sigaction(int sig, const struct old_sigaction __user *act,
struct old_sigaction __user *oact)
{
......
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