From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/s390/kernel/process.c | 416 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 416 insertions(+) create mode 100644 arch/s390/kernel/process.c (limited to 'arch/s390/kernel/process.c') diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c new file mode 100644 index 00000000000..7aea25d6e30 --- /dev/null +++ b/arch/s390/kernel/process.c @@ -0,0 +1,416 @@ +/* + * arch/s390/kernel/process.c + * + * S390 version + * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation + * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), + * Hartmut Penner (hp@de.ibm.com), + * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com), + * + * Derived from "arch/i386/kernel/process.c" + * Copyright (C) 1995, Linus Torvalds + */ + +/* + * This file handles the architecture-dependent parts of process handling.. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include + +asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); + +/* + * Return saved PC of a blocked thread. used in kernel/sched. + * resume in entry.S does not create a new stack frame, it + * just stores the registers %r6-%r15 to the frame given by + * schedule. We want to return the address of the caller of + * schedule, so we have to walk the backchain one time to + * find the frame schedule() store its return address. + */ +unsigned long thread_saved_pc(struct task_struct *tsk) +{ + struct stack_frame *sf; + + sf = (struct stack_frame *) tsk->thread.ksp; + sf = (struct stack_frame *) sf->back_chain; + return sf->gprs[8]; +} + +/* + * Need to know about CPUs going idle? + */ +static struct notifier_block *idle_chain; + +int register_idle_notifier(struct notifier_block *nb) +{ + return notifier_chain_register(&idle_chain, nb); +} +EXPORT_SYMBOL(register_idle_notifier); + +int unregister_idle_notifier(struct notifier_block *nb) +{ + return notifier_chain_unregister(&idle_chain, nb); +} +EXPORT_SYMBOL(unregister_idle_notifier); + +void do_monitor_call(struct pt_regs *regs, long interruption_code) +{ + /* disable monitor call class 0 */ + __ctl_clear_bit(8, 15); + + notifier_call_chain(&idle_chain, CPU_NOT_IDLE, + (void *)(long) smp_processor_id()); +} + +/* + * The idle loop on a S390... + */ +void default_idle(void) +{ + psw_t wait_psw; + unsigned long reg; + int cpu, rc; + + local_irq_disable(); + if (need_resched()) { + local_irq_enable(); + schedule(); + return; + } + + /* CPU is going idle. */ + cpu = smp_processor_id(); + rc = notifier_call_chain(&idle_chain, CPU_IDLE, (void *)(long) cpu); + if (rc != NOTIFY_OK && rc != NOTIFY_DONE) + BUG(); + if (rc != NOTIFY_OK) { + local_irq_enable(); + return; + } + + /* enable monitor call class 0 */ + __ctl_set_bit(8, 15); + +#ifdef CONFIG_HOTPLUG_CPU + if (cpu_is_offline(smp_processor_id())) + cpu_die(); +#endif + + /* + * Wait for external, I/O or machine check interrupt and + * switch off machine check bit after the wait has ended. + */ + wait_psw.mask = PSW_KERNEL_BITS | PSW_MASK_MCHECK | PSW_MASK_WAIT | + PSW_MASK_IO | PSW_MASK_EXT; +#ifndef CONFIG_ARCH_S390X + asm volatile ( + " basr %0,0\n" + "0: la %0,1f-0b(%0)\n" + " st %0,4(%1)\n" + " oi 4(%1),0x80\n" + " lpsw 0(%1)\n" + "1: la %0,2f-1b(%0)\n" + " st %0,4(%1)\n" + " oi 4(%1),0x80\n" + " ni 1(%1),0xf9\n" + " lpsw 0(%1)\n" + "2:" + : "=&a" (reg) : "a" (&wait_psw) : "memory", "cc" ); +#else /* CONFIG_ARCH_S390X */ + asm volatile ( + " larl %0,0f\n" + " stg %0,8(%1)\n" + " lpswe 0(%1)\n" + "0: larl %0,1f\n" + " stg %0,8(%1)\n" + " ni 1(%1),0xf9\n" + " lpswe 0(%1)\n" + "1:" + : "=&a" (reg) : "a" (&wait_psw) : "memory", "cc" ); +#endif /* CONFIG_ARCH_S390X */ +} + +void cpu_idle(void) +{ + for (;;) + default_idle(); +} + +void show_regs(struct pt_regs *regs) +{ + struct task_struct *tsk = current; + + printk("CPU: %d %s\n", tsk->thread_info->cpu, print_tainted()); + printk("Process %s (pid: %d, task: %p, ksp: %p)\n", + current->comm, current->pid, (void *) tsk, + (void *) tsk->thread.ksp); + + show_registers(regs); + /* Show stack backtrace if pt_regs is from kernel mode */ + if (!(regs->psw.mask & PSW_MASK_PSTATE)) + show_trace(0,(unsigned long *) regs->gprs[15]); +} + +extern void kernel_thread_starter(void); + +__asm__(".align 4\n" + "kernel_thread_starter:\n" + " la 2,0(10)\n" + " basr 14,9\n" + " la 2,0\n" + " br 11\n"); + +int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) +{ + struct pt_regs regs; + + memset(®s, 0, sizeof(regs)); + regs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT; + regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE; + regs.gprs[9] = (unsigned long) fn; + regs.gprs[10] = (unsigned long) arg; + regs.gprs[11] = (unsigned long) do_exit; + regs.orig_gpr2 = -1; + + /* Ok, create the new process.. */ + return do_fork(flags | CLONE_VM | CLONE_UNTRACED, + 0, ®s, 0, NULL, NULL); +} + +/* + * Free current thread data structures etc.. + */ +void exit_thread(void) +{ +} + +void flush_thread(void) +{ + clear_used_math(); + clear_tsk_thread_flag(current, TIF_USEDFPU); +} + +void release_thread(struct task_struct *dead_task) +{ +} + +int copy_thread(int nr, unsigned long clone_flags, unsigned long new_stackp, + unsigned long unused, + struct task_struct * p, struct pt_regs * regs) +{ + struct fake_frame + { + struct stack_frame sf; + struct pt_regs childregs; + } *frame; + + frame = ((struct fake_frame *) + (THREAD_SIZE + (unsigned long) p->thread_info)) - 1; + p->thread.ksp = (unsigned long) frame; + /* Store access registers to kernel stack of new process. */ + frame->childregs = *regs; + frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */ + frame->childregs.gprs[15] = new_stackp; + frame->sf.back_chain = 0; + + /* new return point is ret_from_fork */ + frame->sf.gprs[8] = (unsigned long) ret_from_fork; + + /* fake return stack for resume(), don't go back to schedule */ + frame->sf.gprs[9] = (unsigned long) frame; + + /* Save access registers to new thread structure. */ + save_access_regs(&p->thread.acrs[0]); + +#ifndef CONFIG_ARCH_S390X + /* + * save fprs to current->thread.fp_regs to merge them with + * the emulated registers and then copy the result to the child. + */ + save_fp_regs(¤t->thread.fp_regs); + memcpy(&p->thread.fp_regs, ¤t->thread.fp_regs, + sizeof(s390_fp_regs)); + p->thread.user_seg = __pa((unsigned long) p->mm->pgd) | _SEGMENT_TABLE; + /* Set a new TLS ? */ + if (clone_flags & CLONE_SETTLS) + p->thread.acrs[0] = regs->gprs[6]; +#else /* CONFIG_ARCH_S390X */ + /* Save the fpu registers to new thread structure. */ + save_fp_regs(&p->thread.fp_regs); + p->thread.user_seg = __pa((unsigned long) p->mm->pgd) | _REGION_TABLE; + /* Set a new TLS ? */ + if (clone_flags & CLONE_SETTLS) { + if (test_thread_flag(TIF_31BIT)) { + p->thread.acrs[0] = (unsigned int) regs->gprs[6]; + } else { + p->thread.acrs[0] = (unsigned int)(regs->gprs[6] >> 32); + p->thread.acrs[1] = (unsigned int) regs->gprs[6]; + } + } +#endif /* CONFIG_ARCH_S390X */ + /* start new process with ar4 pointing to the correct address space */ + p->thread.mm_segment = get_fs(); + /* Don't copy debug registers */ + memset(&p->thread.per_info,0,sizeof(p->thread.per_info)); + + return 0; +} + +asmlinkage long sys_fork(struct pt_regs regs) +{ + return do_fork(SIGCHLD, regs.gprs[15], ®s, 0, NULL, NULL); +} + +asmlinkage long sys_clone(struct pt_regs regs) +{ + unsigned long clone_flags; + unsigned long newsp; + int __user *parent_tidptr, *child_tidptr; + + clone_flags = regs.gprs[3]; + newsp = regs.orig_gpr2; + parent_tidptr = (int __user *) regs.gprs[4]; + child_tidptr = (int __user *) regs.gprs[5]; + if (!newsp) + newsp = regs.gprs[15]; + return do_fork(clone_flags, newsp, ®s, 0, + parent_tidptr, child_tidptr); +} + +/* + * 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. + */ +asmlinkage long sys_vfork(struct pt_regs regs) +{ + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, + regs.gprs[15], ®s, 0, NULL, NULL); +} + +/* + * sys_execve() executes a new program. + */ +asmlinkage long sys_execve(struct pt_regs regs) +{ + int error; + char * filename; + + filename = getname((char __user *) regs.orig_gpr2); + error = PTR_ERR(filename); + if (IS_ERR(filename)) + goto out; + error = do_execve(filename, (char __user * __user *) regs.gprs[3], + (char __user * __user *) regs.gprs[4], ®s); + if (error == 0) { + task_lock(current); + current->ptrace &= ~PT_DTRACE; + task_unlock(current); + current->thread.fp_regs.fpc = 0; + if (MACHINE_HAS_IEEE) + asm volatile("sfpc %0,%0" : : "d" (0)); + } + putname(filename); +out: + return error; +} + + +/* + * fill in the FPU structure for a core dump. + */ +int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs) +{ +#ifndef CONFIG_ARCH_S390X + /* + * save fprs to current->thread.fp_regs to merge them with + * the emulated registers and then copy the result to the dump. + */ + save_fp_regs(¤t->thread.fp_regs); + memcpy(fpregs, ¤t->thread.fp_regs, sizeof(s390_fp_regs)); +#else /* CONFIG_ARCH_S390X */ + save_fp_regs(fpregs); +#endif /* CONFIG_ARCH_S390X */ + return 1; +} + +/* + * fill in the user structure for a core dump.. + */ +void dump_thread(struct pt_regs * regs, struct user * dump) +{ + +/* changed the size calculations - should hopefully work better. lbt */ + dump->magic = CMAGIC; + dump->start_code = 0; + dump->start_stack = regs->gprs[15] & ~(PAGE_SIZE - 1); + dump->u_tsize = current->mm->end_code >> PAGE_SHIFT; + dump->u_dsize = (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 = (TASK_SIZE - dump->start_stack) >> PAGE_SHIFT; + memcpy(&dump->regs, regs, sizeof(s390_regs)); + dump_fpu (regs, &dump->regs.fp_regs); + dump->regs.per_info = current->thread.per_info; +} + +unsigned long get_wchan(struct task_struct *p) +{ + struct stack_frame *sf, *low, *high; + unsigned long return_address; + int count; + + if (!p || p == current || p->state == TASK_RUNNING || !p->thread_info) + return 0; + low = (struct stack_frame *) p->thread_info; + high = (struct stack_frame *) + ((unsigned long) p->thread_info + THREAD_SIZE) - 1; + sf = (struct stack_frame *) (p->thread.ksp & PSW_ADDR_INSN); + if (sf <= low || sf > high) + return 0; + for (count = 0; count < 16; count++) { + sf = (struct stack_frame *) (sf->back_chain & PSW_ADDR_INSN); + if (sf <= low || sf > high) + return 0; + return_address = sf->gprs[8] & PSW_ADDR_INSN; + if (!in_sched_functions(return_address)) + return return_address; + } + return 0; +} + -- cgit v1.2.3