From: Al Viro Date: Thu, 20 Sep 2012 13:28:25 +0000 (-0400) Subject: um: kill thread->forking X-Git-Tag: firefly_0821_release~3680^2~1868^2~18 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a4d94ff8aa864c05b33c2de1f8c5d0176d7a4b63;p=firefly-linux-kernel-4.4.55.git um: kill thread->forking we only use that to tell copy_thread() done by syscall from that done by kernel_thread(). However, it's easier to do simply by checking PF_KTHREAD in thread flags. Merge sys_clone() guts for 32bit and 64bit, while we are at it... Signed-off-by: Al Viro --- diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h index 69f1c57a8d0d..33a6a2423bd2 100644 --- a/arch/um/include/asm/processor-generic.h +++ b/arch/um/include/asm/processor-generic.h @@ -20,14 +20,6 @@ struct mm_struct; struct thread_struct { struct task_struct *saved_task; - /* - * This flag is set to 1 before calling do_fork (and analyzed in - * copy_thread) to mark that we are begin called from userspace (fork / - * vfork / clone), and reset to 0 after. It is left to 0 when called - * from kernelspace (i.e. kernel_thread() or fork_idle(), - * as of 2.6.11). - */ - int forking; struct pt_regs regs; int singlestep_syscall; void *fault_addr; @@ -58,7 +50,6 @@ struct thread_struct { #define INIT_THREAD \ { \ - .forking = 0, \ .regs = EMPTY_REGS, \ .fault_addr = NULL, \ .prev_sched = NULL, \ diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index 57fc7028714a..c5f5afa50745 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -181,11 +181,12 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, struct pt_regs *regs) { void (*handler)(void); + int kthread = current->flags & PF_KTHREAD; int ret = 0; p->thread = (struct thread_struct) INIT_THREAD; - if (current->thread.forking) { + if (!kthread) { memcpy(&p->thread.regs.regs, ®s->regs, sizeof(p->thread.regs.regs)); PT_REGS_SET_SYSCALL_RETURN(&p->thread.regs, 0); @@ -195,8 +196,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, handler = fork_handler; arch_copy_thread(¤t->thread.arch, &p->thread.arch); - } - else { + } else { get_safe_registers(p->thread.regs.regs.gp, p->thread.regs.regs.fp); p->thread.request.u.thread = current->thread.request.u.thread; handler = new_thread_handler; @@ -204,7 +204,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, new_thread(task_stack_page(p), &p->thread.switch_buf, handler); - if (current->thread.forking) { + if (!kthread) { clear_flushed_tls(p); /* diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c index f958cb876ee3..a4c6d8eee74c 100644 --- a/arch/um/kernel/syscall.c +++ b/arch/um/kernel/syscall.c @@ -17,25 +17,25 @@ long sys_fork(void) { - long ret; - - current->thread.forking = 1; - ret = do_fork(SIGCHLD, UPT_SP(¤t->thread.regs.regs), + return do_fork(SIGCHLD, UPT_SP(¤t->thread.regs.regs), ¤t->thread.regs, 0, NULL, NULL); - current->thread.forking = 0; - return ret; } long sys_vfork(void) { - long ret; - - current->thread.forking = 1; - ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, UPT_SP(¤t->thread.regs.regs), ¤t->thread.regs, 0, NULL, NULL); - current->thread.forking = 0; - return ret; +} + +long sys_clone(unsigned long clone_flags, unsigned long newsp, + void __user *parent_tid, void __user *child_tid) +{ + if (!newsp) + newsp = UPT_SP(¤t->thread.regs.regs); + + return do_fork(clone_flags, newsp, ¤t->thread.regs, 0, parent_tid, + child_tid); } long old_mmap(unsigned long addr, unsigned long len, diff --git a/arch/x86/um/shared/sysdep/syscalls.h b/arch/x86/um/shared/sysdep/syscalls.h index bd9a89b67e41..ca255a805ed9 100644 --- a/arch/x86/um/shared/sysdep/syscalls.h +++ b/arch/x86/um/shared/sysdep/syscalls.h @@ -1,3 +1,5 @@ +extern long sys_clone(unsigned long clone_flags, unsigned long newsp, + void __user *parent_tid, void __user *child_tid); #ifdef __i386__ #include "syscalls_32.h" #else diff --git a/arch/x86/um/sys_call_table_32.c b/arch/x86/um/sys_call_table_32.c index 68d1dc91b37b..b5408cecac6c 100644 --- a/arch/x86/um/sys_call_table_32.c +++ b/arch/x86/um/sys_call_table_32.c @@ -28,7 +28,7 @@ #define ptregs_execve sys_execve #define ptregs_iopl sys_iopl #define ptregs_vm86old sys_vm86old -#define ptregs_clone sys_clone +#define ptregs_clone i386_clone #define ptregs_vm86 sys_vm86 #define ptregs_sigaltstack sys_sigaltstack #define ptregs_vfork sys_vfork diff --git a/arch/x86/um/syscalls_32.c b/arch/x86/um/syscalls_32.c index b853e8600b9d..db444c7218fe 100644 --- a/arch/x86/um/syscalls_32.c +++ b/arch/x86/um/syscalls_32.c @@ -3,37 +3,24 @@ * Licensed under the GPL */ -#include "linux/sched.h" -#include "linux/shm.h" -#include "linux/ipc.h" -#include "linux/syscalls.h" -#include "asm/mman.h" -#include "asm/uaccess.h" -#include "asm/unistd.h" +#include +#include /* * The prototype on i386 is: * - * int clone(int flags, void * child_stack, int * parent_tidptr, struct user_desc * newtls, int * child_tidptr) + * 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 sys_clone(unsigned long clone_flags, unsigned long newsp, - int __user *parent_tid, void *newtls, int __user *child_tid) +long i386_clone(unsigned long clone_flags, unsigned long newsp, + int __user *parent_tid, void *newtls, int __user *child_tid) { - long ret; - - if (!newsp) - newsp = UPT_SP(¤t->thread.regs.regs); - - current->thread.forking = 1; - ret = do_fork(clone_flags, newsp, ¤t->thread.regs, 0, parent_tid, - child_tid); - current->thread.forking = 0; - return ret; + 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) { diff --git a/arch/x86/um/syscalls_64.c b/arch/x86/um/syscalls_64.c index f3d82bb6e15a..adb08eb5c22a 100644 --- a/arch/x86/um/syscalls_64.c +++ b/arch/x86/um/syscalls_64.c @@ -5,12 +5,9 @@ * Licensed under the GPL */ -#include "linux/linkage.h" -#include "linux/personality.h" -#include "linux/utsname.h" -#include "asm/prctl.h" /* XXX This should get the constants from libc */ -#include "asm/uaccess.h" -#include "os.h" +#include +#include /* XXX This should get the constants from libc */ +#include long arch_prctl(struct task_struct *task, int code, unsigned long __user *addr) { @@ -79,20 +76,6 @@ long sys_arch_prctl(int code, unsigned long addr) return arch_prctl(current, code, (unsigned long __user *) addr); } -long sys_clone(unsigned long clone_flags, unsigned long newsp, - void __user *parent_tid, void __user *child_tid) -{ - long ret; - - if (!newsp) - newsp = UPT_SP(¤t->thread.regs.regs); - current->thread.forking = 1; - ret = do_fork(clone_flags, newsp, ¤t->thread.regs, 0, parent_tid, - child_tid); - current->thread.forking = 0; - return ret; -} - void arch_switch_to(struct task_struct *to) { if ((to->thread.arch.fs == 0) || (to->mm == NULL))