diff options
Diffstat (limited to 'arch/m68k/kernel/process.c')
| -rw-r--r-- | arch/m68k/kernel/process.c | 190 |
1 files changed, 45 insertions, 145 deletions
diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c index c488e3cfab5..c55ff719fa7 100644 --- a/arch/m68k/kernel/process.c +++ b/arch/m68k/kernel/process.c @@ -25,6 +25,7 @@ #include <linux/reboot.h> #include <linux/init_task.h> #include <linux/mqueue.h> +#include <linux/rcupdate.h> #include <asm/uaccess.h> #include <asm/traps.h> @@ -34,6 +35,7 @@ asmlinkage void ret_from_fork(void); +asmlinkage void ret_from_kernel_thread(void); /* @@ -49,38 +51,16 @@ unsigned long thread_saved_pc(struct task_struct *tsk) return sw->retpc; } -/* - * The idle loop on an m68k.. - */ -static void default_idle(void) +void arch_cpu_idle(void) { - if (!need_resched()) #if defined(MACH_ATARI_ONLY) - /* block out HSYNC on the atari (falcon) */ - __asm__("stop #0x2200" : : : "cc"); + /* block out HSYNC on the atari (falcon) */ + __asm__("stop #0x2200" : : : "cc"); #else - __asm__("stop #0x2000" : : : "cc"); + __asm__("stop #0x2000" : : : "cc"); #endif } -void (*idle)(void) = default_idle; - -/* - * The idle thread. There's no useful work to be - * done, so just try to conserve power and have a - * low exit latency (ie sit in a loop waiting for - * somebody to say that they'd like to reschedule) - */ -void cpu_idle(void) -{ - /* endless idle loop with no priority at all */ - while (1) { - while (!need_resched()) - idle(); - schedule_preempt_disabled(); - } -} - void machine_restart(char * __unused) { if (mach_reset) @@ -120,51 +100,6 @@ void show_regs(struct pt_regs * regs) printk("USP: %08lx\n", rdusp()); } -/* - * Create a kernel thread - */ -int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) -{ - int pid; - mm_segment_t fs; - - fs = get_fs(); - set_fs (KERNEL_DS); - - { - register long retval __asm__ ("d0"); - register long clone_arg __asm__ ("d1") = flags | CLONE_VM | CLONE_UNTRACED; - - retval = __NR_clone; - __asm__ __volatile__ - ("clrl %%d2\n\t" - "trap #0\n\t" /* Linux/m68k system call */ - "tstl %0\n\t" /* child or parent */ - "jne 1f\n\t" /* parent - jump */ -#ifdef CONFIG_MMU - "lea %%sp@(%c7),%6\n\t" /* reload current */ - "movel %6@,%6\n\t" -#endif - "movel %3,%%sp@-\n\t" /* push argument */ - "jsr %4@\n\t" /* call fn */ - "movel %0,%%d1\n\t" /* pass exit value */ - "movel %2,%%d0\n\t" /* exit */ - "trap #0\n" - "1:" - : "+d" (retval) - : "i" (__NR_clone), "i" (__NR_exit), - "r" (arg), "a" (fn), "d" (clone_arg), "r" (current), - "i" (-THREAD_SIZE) - : "d2"); - - pid = retval; - } - - set_fs (fs); - return pid; -} -EXPORT_SYMBOL(kernel_thread); - void flush_thread(void) { current->thread.fs = __USER_DS; @@ -177,69 +112,35 @@ void flush_thread(void) } /* - * "m68k_fork()".. By the time we get here, the - * non-volatile registers have also been saved on the - * stack. We do some ugly pointer stuff here.. (see - * also copy_thread) + * Why not generic sys_clone, you ask? m68k passes all arguments on stack. + * And we need all registers saved, which means a bunch of stuff pushed + * on top of pt_regs, which means that sys_clone() arguments would be + * buried. We could, of course, copy them, but it's too costly for no + * good reason - generic clone() would have to copy them *again* for + * do_fork() anyway. So in this case it's actually better to pass pt_regs * + * and extract arguments for do_fork() from there. Eventually we might + * go for calling do_fork() directly from the wrapper, but only after we + * are finished with do_fork() prototype conversion. */ - -asmlinkage int m68k_fork(struct pt_regs *regs) -{ -#ifdef CONFIG_MMU - return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL); -#else - return -EINVAL; -#endif -} - -asmlinkage int m68k_vfork(struct pt_regs *regs) -{ - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, rdusp(), regs, 0, - NULL, NULL); -} - asmlinkage int m68k_clone(struct pt_regs *regs) { - unsigned long clone_flags; - unsigned long newsp; - int __user *parent_tidptr, *child_tidptr; - - /* syscall2 puts clone_flags in d1 and usp in d2 */ - clone_flags = regs->d1; - newsp = regs->d2; - parent_tidptr = (int __user *)regs->d3; - child_tidptr = (int __user *)regs->d4; - if (!newsp) - newsp = rdusp(); - return do_fork(clone_flags, newsp, regs, 0, - parent_tidptr, child_tidptr); + /* regs will be equal to current_pt_regs() */ + return do_fork(regs->d1, regs->d2, 0, + (int __user *)regs->d3, (int __user *)regs->d4); } int copy_thread(unsigned long clone_flags, unsigned long usp, - unsigned long unused, - struct task_struct * p, struct pt_regs * regs) + unsigned long arg, struct task_struct *p) { - struct pt_regs * childregs; - struct switch_stack * childstack, *stack; - unsigned long *retp; + struct fork_frame { + struct switch_stack sw; + struct pt_regs regs; + } *frame; - childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1; + frame = (struct fork_frame *) (task_stack_page(p) + THREAD_SIZE) - 1; - *childregs = *regs; - childregs->d0 = 0; - - retp = ((unsigned long *) regs); - stack = ((struct switch_stack *) retp) - 1; - - childstack = ((struct switch_stack *) childregs) - 1; - *childstack = *stack; - childstack->retpc = (unsigned long)ret_from_fork; - - p->thread.usp = usp; - p->thread.ksp = (unsigned long)childstack; - - if (clone_flags & CLONE_SETTLS) - task_thread_info(p)->tp_value = regs->d5; + p->thread.ksp = (unsigned long)frame; + p->thread.esp0 = (unsigned long)&frame->regs; /* * Must save the current SFC/DFC value, NOT the value when @@ -247,6 +148,25 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, */ p->thread.fs = get_fs().seg; + if (unlikely(p->flags & PF_KTHREAD)) { + /* kernel thread */ + memset(frame, 0, sizeof(struct fork_frame)); + frame->regs.sr = PS_S; + frame->sw.a3 = usp; /* function */ + frame->sw.d7 = arg; + frame->sw.retpc = (unsigned long)ret_from_kernel_thread; + p->thread.usp = 0; + return 0; + } + memcpy(frame, container_of(current_pt_regs(), struct fork_frame, regs), + sizeof(struct fork_frame)); + frame->regs.d0 = 0; + frame->sw.retpc = (unsigned long)ret_from_fork; + p->thread.usp = usp ?: rdusp(); + + if (clone_flags & CLONE_SETTLS) + task_thread_info(p)->tp_value = frame->regs.d5; + #ifdef CONFIG_FPU if (!FPU_IS_EMU) { /* Copy the current fpu state */ @@ -334,26 +254,6 @@ int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu) EXPORT_SYMBOL(dump_fpu); #endif /* CONFIG_FPU */ -/* - * sys_execve() executes a new program. - */ -asmlinkage int sys_execve(const char __user *name, - const char __user *const __user *argv, - const char __user *const __user *envp) -{ - int error; - char * filename; - struct pt_regs *regs = (struct pt_regs *) &name; - - filename = getname(name); - error = PTR_ERR(filename); - if (IS_ERR(filename)) - return error; - error = do_execve(filename, argv, envp, regs); - putname(filename); - return error; -} - unsigned long get_wchan(struct task_struct *p) { unsigned long fp, pc; |