From: Al Viro Date: Tue, 23 Oct 2012 02:34:11 +0000 (-0400) Subject: x86, um: switch to generic fork/vfork/clone X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=1d4b4b2994b5fc208963c0b795291f8c1f18becf;p=openwrt%2Fstaging%2Fblogic.git x86, um: switch to generic fork/vfork/clone Signed-off-by: Al Viro --- diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c index 3a875226c8ef..c1d0ae069b53 100644 --- a/arch/um/kernel/syscall.c +++ b/arch/um/kernel/syscall.c @@ -14,25 +14,6 @@ #include #include -long sys_fork(void) -{ - return do_fork(SIGCHLD, 0, - ¤t->thread.regs, 0, NULL, NULL); -} - -long sys_vfork(void) -{ - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, - ¤t->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, ¤t->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) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 46c3bff3ced2..0df6e7d84539 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -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 diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index 076745fc8045..32e6f05ddaaa 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -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 diff --git a/arch/x86/ia32/sys_ia32.c b/arch/x86/ia32/sys_ia32.c index 86d68d1c8806..d0b689ba7be2 100644 --- a/arch/x86/ia32/sys_ia32.c +++ b/arch/x86/ia32/sys_ia32.c @@ -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. diff --git a/arch/x86/include/asm/sys_ia32.h b/arch/x86/include/asm/sys_ia32.h index a9a8cf3da49d..c76fae4d90be 100644 --- a/arch/x86/include/asm/sys_ia32.h +++ b/arch/x86/include/asm/sys_ia32.h @@ -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); diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h index 9e5aef3a2598..f7252d11416b 100644 --- a/arch/x86/include/asm/syscalls.h +++ b/arch/x86/include/asm/syscalls.h @@ -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); diff --git a/arch/x86/include/asm/unistd.h b/arch/x86/include/asm/unistd.h index 16f3fc6ebf2e..0e7dea7d3669 100644 --- a/arch/x86/include/asm/unistd.h +++ b/arch/x86/include/asm/unistd.h @@ -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 diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index 88b725aa1d52..c763116c5359 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -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 diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 1328fe49a3f1..2363e820ed68 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -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 diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index b644e1c765dc..fe9459593257 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -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 */ diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 44e0bff38e72..16efa974532b 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -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; diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 16c6365e2b86..74aac76c6e34 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -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)); diff --git a/arch/x86/syscalls/syscall_32.tbl b/arch/x86/syscalls/syscall_32.tbl index a47103fbc692..ee3c220ee500 100644 --- a/arch/x86/syscalls/syscall_32.tbl +++ b/arch/x86/syscalls/syscall_32.tbl @@ -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 diff --git a/arch/x86/um/Kconfig b/arch/x86/um/Kconfig index 07611759ce35..8f51c39750d1 100644 --- a/arch/x86/um/Kconfig +++ b/arch/x86/um/Kconfig @@ -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 diff --git a/arch/x86/um/sys_call_table_32.c b/arch/x86/um/sys_call_table_32.c index 232e60504b3a..812e98c098e4 100644 --- a/arch/x86/um/sys_call_table_32.c +++ b/arch/x86/um/sys_call_table_32.c @@ -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 diff --git a/arch/x86/um/syscalls_32.c b/arch/x86/um/syscalls_32.c index db444c7218fe..e8bcea99acdb 100644 --- a/arch/x86/um/syscalls_32.c +++ b/arch/x86/um/syscalls_32.c @@ -6,21 +6,6 @@ #include #include -/* - * 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) {