From 1856ab6db1296c9c31ad58263d49ee9b75568ddb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 15 Oct 2012 15:26:11 -0400 Subject: score: switch to generic kernel_thread()/kernel_execve() Signed-off-by: Al Viro --- arch/score/Kconfig | 2 ++ arch/score/include/asm/processor.h | 1 - arch/score/kernel/entry.S | 7 +++++ arch/score/kernel/process.c | 55 ++++++++++---------------------------- arch/score/kernel/sys_score.c | 30 --------------------- 5 files changed, 23 insertions(+), 72 deletions(-) (limited to 'arch/score') diff --git a/arch/score/Kconfig b/arch/score/Kconfig index 4f93a431a45..a285e78fb9c 100644 --- a/arch/score/Kconfig +++ b/arch/score/Kconfig @@ -13,6 +13,8 @@ config SCORE select GENERIC_CLOCKEVENTS select HAVE_MOD_ARCH_SPECIFIC select MODULES_USE_ELF_REL + select GENERIC_KERNEL_THREAD + select GENERIC_KERNEL_EXECVE choice prompt "System type" diff --git a/arch/score/include/asm/processor.h b/arch/score/include/asm/processor.h index ab3aceb5420..d9a922d8711 100644 --- a/arch/score/include/asm/processor.h +++ b/arch/score/include/asm/processor.h @@ -13,7 +13,6 @@ struct task_struct; */ extern void (*cpu_wait)(void); -extern long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); extern unsigned long thread_saved_pc(struct task_struct *tsk); extern void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp); diff --git a/arch/score/kernel/entry.S b/arch/score/kernel/entry.S index 83bb96079c4..74a5cc7f596 100644 --- a/arch/score/kernel/entry.S +++ b/arch/score/kernel/entry.S @@ -278,6 +278,13 @@ need_resched: nop #endif +ENTRY(ret_from_kernel_thread) + bl schedule_tail # r4=struct task_struct *prev + nop + mv r4, r13 + brl r12 + j syscall_exit + ENTRY(ret_from_fork) bl schedule_tail # r4=struct task_struct *prev diff --git a/arch/score/kernel/process.c b/arch/score/kernel/process.c index 637970cfd3f..6f311cf64b9 100644 --- a/arch/score/kernel/process.c +++ b/arch/score/kernel/process.c @@ -60,6 +60,7 @@ void __noreturn cpu_idle(void) } void ret_from_fork(void); +void ret_from_kernel_thread(void); void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) { @@ -86,29 +87,27 @@ void flush_thread(void) {} * set up the kernel stack and exception frames for a new process */ int copy_thread(unsigned long clone_flags, unsigned long usp, - unsigned long unused, + unsigned long arg, struct task_struct *p, struct pt_regs *regs) { struct thread_info *ti = task_thread_info(p); struct pt_regs *childregs = task_pt_regs(p); - p->set_child_tid = NULL; - p->clear_child_tid = NULL; - - *childregs = *regs; - childregs->regs[7] = 0; /* Clear error flag */ - childregs->regs[4] = 0; /* Child gets zero as return value */ - regs->regs[4] = p->pid; - - if (childregs->cp0_psr & 0x8) { /* test kernel fork or user fork */ - childregs->regs[0] = usp; /* user fork */ + p->thread.reg0 = (unsigned long) childregs; + if (unlikely(!regs)) { + memset(childregs, 0, sizeof(struct pt_regs)); + p->thread->reg12 = usp; + p->thread->reg13 = arg; + p->thread.reg3 = (unsigned long) ret_from_kernel_thread; } else { - childregs->regs[28] = (unsigned long) ti; /* kernel fork */ - childregs->regs[0] = (unsigned long) childregs; + *childregs = *regs; + childregs->regs[7] = 0; /* Clear error flag */ + childregs->regs[4] = 0; /* Child gets zero as return value */ + childregs->regs[0] = usp; /* user fork */ + regs->regs[4] = p->pid; /* WTF? */ + p->thread.reg3 = (unsigned long) ret_from_fork; } - p->thread.reg0 = (unsigned long) childregs; - p->thread.reg3 = (unsigned long) ret_from_fork; p->thread.cp0_psr = 0; return 0; @@ -120,32 +119,6 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r) return 1; } -static void __noreturn -kernel_thread_helper(void *unused0, int (*fn)(void *), - void *arg, void *unused1) -{ - do_exit(fn(arg)); -} - -/* - * Create a kernel thread. - */ -long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) -{ - struct pt_regs regs; - - memset(®s, 0, sizeof(regs)); - - regs.regs[6] = (unsigned long) arg; - regs.regs[5] = (unsigned long) fn; - regs.cp0_epc = (unsigned long) kernel_thread_helper; - regs.cp0_psr = (regs.cp0_psr & ~(0x1|0x4|0x8)) | \ - ((regs.cp0_psr & 0x3) << 2); - - return do_fork(flags | CLONE_VM | CLONE_UNTRACED, \ - 0, ®s, 0, NULL, NULL); -} - unsigned long thread_saved_pc(struct task_struct *tsk) { return task_pt_regs(tsk)->cp0_epc; diff --git a/arch/score/kernel/sys_score.c b/arch/score/kernel/sys_score.c index d45cf00a335..5a682fce1fd 100644 --- a/arch/score/kernel/sys_score.c +++ b/arch/score/kernel/sys_score.c @@ -107,33 +107,3 @@ score_execve(struct pt_regs *regs) putname(filename); return error; } - -/* - * Do a system call from kernel instead of calling sys_execve so we - * end up with proper pt_regs. - */ -asmlinkage -int kernel_execve(const char *filename, - const char *const argv[], - const char *const envp[]) -{ - register unsigned long __r4 asm("r4") = (unsigned long) filename; - register unsigned long __r5 asm("r5") = (unsigned long) argv; - register unsigned long __r6 asm("r6") = (unsigned long) envp; - register unsigned long __r7 asm("r7"); - - __asm__ __volatile__ (" \n" - "ldi r27, %5 \n" - "syscall \n" - "mv %0, r4 \n" - "mv %1, r7 \n" - : "=&r" (__r4), "=r" (__r7) - : "r" (__r4), "r" (__r5), "r" (__r6), "i" (__NR_execve) - : "r8", "r9", "r10", "r11", "r22", "r23", "r24", "r25", - "r26", "r27", "memory"); - - if (__r7 == 0) - return __r4; - - return -__r4; -} -- cgit v1.2.3