diff options
Diffstat (limited to 'arch/m68k/kernel/process.c')
| -rw-r--r-- | arch/m68k/kernel/process.c | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/arch/m68k/kernel/process.c b/arch/m68k/kernel/process.c new file mode 100644 index 00000000000..93b043e2a43 --- /dev/null +++ b/arch/m68k/kernel/process.c @@ -0,0 +1,405 @@ +/* + * linux/arch/m68k/kernel/process.c + * + * Copyright (C) 1995 Hamish Macdonald + * + * 68060 fixes by Jesper Skov + */ + +/* + * This file handles the architecture-dependent parts of process handling.. + */ + +#include <linux/config.h> +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/stddef.h> +#include <linux/unistd.h> +#include <linux/ptrace.h> +#include <linux/slab.h> +#include <linux/user.h> +#include <linux/a.out.h> +#include <linux/reboot.h> +#include <linux/init_task.h> +#include <linux/mqueue.h> + +#include <asm/uaccess.h> +#include <asm/system.h> +#include <asm/traps.h> +#include <asm/machdep.h> +#include <asm/setup.h> +#include <asm/pgtable.h> + +/* + * Initial task/thread structure. Make this a per-architecture thing, + * because different architectures tend to have different + * alignment requirements and potentially different initial + * setup. + */ +static struct fs_struct init_fs = INIT_FS; +static struct files_struct init_files = INIT_FILES; +static struct signal_struct init_signals = INIT_SIGNALS(init_signals); +static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); +struct mm_struct init_mm = INIT_MM(init_mm); + +EXPORT_SYMBOL(init_mm); + +union thread_union init_thread_union +__attribute__((section(".data.init_task"), aligned(THREAD_SIZE))) + = { INIT_THREAD_INFO(init_task) }; + +/* initial task structure */ +struct task_struct init_task = INIT_TASK(init_task); + +EXPORT_SYMBOL(init_task); + +asmlinkage void ret_from_fork(void); + + +/* + * Return saved PC from a blocked thread + */ +unsigned long thread_saved_pc(struct task_struct *tsk) +{ + struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp; + /* Check whether the thread is blocked in resume() */ + if (in_sched_functions(sw->retpc)) + return ((unsigned long *)sw->a6)[1]; + else + return sw->retpc; +} + +/* + * The idle loop on an m68k.. + */ +void default_idle(void) +{ + if (!need_resched()) +#if defined(MACH_ATARI_ONLY) && !defined(CONFIG_HADES) + /* block out HSYNC on the atari (falcon) */ + __asm__("stop #0x2200" : : : "cc"); +#else + __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(); + } +} + +void machine_restart(char * __unused) +{ + if (mach_reset) + mach_reset(); + for (;;); +} + +EXPORT_SYMBOL(machine_restart); + +void machine_halt(void) +{ + if (mach_halt) + mach_halt(); + for (;;); +} + +EXPORT_SYMBOL(machine_halt); + +void machine_power_off(void) +{ + if (mach_power_off) + mach_power_off(); + for (;;); +} + +EXPORT_SYMBOL(machine_power_off); + +void show_regs(struct pt_regs * regs) +{ + printk("\n"); + printk("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n", + regs->format, regs->vector, regs->pc, regs->sr, print_tainted()); + printk("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n", + regs->orig_d0, regs->d0, regs->a2, regs->a1); + printk("A0: %08lx D5: %08lx D4: %08lx\n", + regs->a0, regs->d5, regs->d4); + printk("D3: %08lx D2: %08lx D1: %08lx\n", + regs->d3, regs->d2, regs->d1); + if (!(regs->sr & PS_S)) + 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 */ + "lea %%sp@(%c7),%6\n\t" /* reload current */ + "movel %6@,%6\n\t" + "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; +} + +void flush_thread(void) +{ + unsigned long zero = 0; + set_fs(USER_DS); + current->thread.fs = __USER_DS; + if (!FPU_IS_EMU) + asm volatile (".chip 68k/68881\n\t" + "frestore %0@\n\t" + ".chip 68k" : : "a" (&zero)); +} + +/* + * "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) + */ + +asmlinkage int m68k_fork(struct pt_regs *regs) +{ + return do_fork(SIGCHLD, rdusp(), regs, 0, NULL, NULL); +} + +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 *parent_tidptr, *child_tidptr; + + /* syscall2 puts clone_flags in d1 and usp in d2 */ + clone_flags = regs->d1; + newsp = regs->d2; + parent_tidptr = (int *)regs->d3; + child_tidptr = (int *)regs->d4; + if (!newsp) + newsp = rdusp(); + return do_fork(clone_flags, newsp, regs, 0, + parent_tidptr, child_tidptr); +} + +int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, + unsigned long unused, + struct task_struct * p, struct pt_regs * regs) +{ + struct pt_regs * childregs; + struct switch_stack * childstack, *stack; + unsigned long stack_offset, *retp; + + stack_offset = THREAD_SIZE - sizeof(struct pt_regs); + childregs = (struct pt_regs *) ((unsigned long) (p->thread_info) + stack_offset); + + *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; + /* + * Must save the current SFC/DFC value, NOT the value when + * the parent was last descheduled - RGH 10-08-96 + */ + p->thread.fs = get_fs().seg; + + if (!FPU_IS_EMU) { + /* Copy the current fpu state */ + asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory"); + + if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) + asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t" + "fmoveml %/fpiar/%/fpcr/%/fpsr,%1" + : : "m" (p->thread.fp[0]), "m" (p->thread.fpcntl[0]) + : "memory"); + /* Restore the state in case the fpu was busy */ + asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0])); + } + + return 0; +} + +/* Fill in the fpu structure for a core dump. */ + +int dump_fpu (struct pt_regs *regs, struct user_m68kfp_struct *fpu) +{ + char fpustate[216]; + + if (FPU_IS_EMU) { + int i; + + memcpy(fpu->fpcntl, current->thread.fpcntl, 12); + memcpy(fpu->fpregs, current->thread.fp, 96); + /* Convert internal fpu reg representation + * into long double format + */ + for (i = 0; i < 24; i += 3) + fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) | + ((fpu->fpregs[i] & 0x0000ffff) << 16); + return 1; + } + + /* First dump the fpu context to avoid protocol violation. */ + asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory"); + if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2]) + return 0; + + asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0" + :: "m" (fpu->fpcntl[0]) + : "memory"); + asm volatile ("fmovemx %/fp0-%/fp7,%0" + :: "m" (fpu->fpregs[0]) + : "memory"); + return 1; +} + +/* + * fill in the user structure for a core dump.. + */ +void dump_thread(struct pt_regs * regs, struct user * dump) +{ + struct switch_stack *sw; + +/* changed the size calculations - should hopefully work better. lbt */ + dump->magic = CMAGIC; + dump->start_code = 0; + dump->start_stack = rdusp() & ~(PAGE_SIZE - 1); + dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT; + dump->u_dsize = ((unsigned long) (current->mm->brk + + (PAGE_SIZE-1))) >> PAGE_SHIFT; + dump->u_dsize -= dump->u_tsize; + dump->u_ssize = 0; + + if (dump->start_stack < TASK_SIZE) + dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT; + + dump->u_ar0 = (struct user_regs_struct *)((int)&dump->regs - (int)dump); + sw = ((struct switch_stack *)regs) - 1; + dump->regs.d1 = regs->d1; + dump->regs.d2 = regs->d2; + dump->regs.d3 = regs->d3; + dump->regs.d4 = regs->d4; + dump->regs.d5 = regs->d5; + dump->regs.d6 = sw->d6; + dump->regs.d7 = sw->d7; + dump->regs.a0 = regs->a0; + dump->regs.a1 = regs->a1; + dump->regs.a2 = regs->a2; + dump->regs.a3 = sw->a3; + dump->regs.a4 = sw->a4; + dump->regs.a5 = sw->a5; + dump->regs.a6 = sw->a6; + dump->regs.d0 = regs->d0; + dump->regs.orig_d0 = regs->orig_d0; + dump->regs.stkadj = regs->stkadj; + dump->regs.sr = regs->sr; + dump->regs.pc = regs->pc; + dump->regs.fmtvec = (regs->format << 12) | regs->vector; + /* dump floating point stuff */ + dump->u_fpvalid = dump_fpu (regs, &dump->m68kfp); +} + +/* + * sys_execve() executes a new program. + */ +asmlinkage int sys_execve(char *name, char **argv, char **envp) +{ + int error; + char * filename; + struct pt_regs *regs = (struct pt_regs *) &name; + + lock_kernel(); + filename = getname(name); + error = PTR_ERR(filename); + if (IS_ERR(filename)) + goto out; + error = do_execve(filename, argv, envp, regs); + putname(filename); +out: + unlock_kernel(); + return error; +} + +unsigned long get_wchan(struct task_struct *p) +{ + unsigned long fp, pc; + unsigned long stack_page; + int count = 0; + if (!p || p == current || p->state == TASK_RUNNING) + return 0; + + stack_page = (unsigned long)(p->thread_info); + fp = ((struct switch_stack *)p->thread.ksp)->a6; + do { + if (fp < stack_page+sizeof(struct thread_info) || + fp >= 8184+stack_page) + return 0; + pc = ((unsigned long *)fp)[1]; + if (!in_sched_functions(pc)) + return pc; + fp = *(unsigned long *) fp; + } while (count++ < 16); + return 0; +} |