+++ /dev/null
-/*
- * linux/arch/ppc64/kernel/process.c
- *
- * Derived from "arch/i386/kernel/process.c"
- * Copyright (C) 1995 Linus Torvalds
- *
- * Updated and modified by Cort Dougan (cort@cs.nmt.edu) and
- * Paul Mackerras (paulus@cs.anu.edu.au)
- *
- * PowerPC version
- * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <linux/config.h>
-#include <linux/module.h>
-#include <linux/errno.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/slab.h>
-#include <linux/user.h>
-#include <linux/elf.h>
-#include <linux/init.h>
-#include <linux/init_task.h>
-#include <linux/prctl.h>
-#include <linux/ptrace.h>
-#include <linux/kallsyms.h>
-#include <linux/interrupt.h>
-#include <linux/utsname.h>
-#include <linux/kprobes.h>
-
-#include <asm/pgtable.h>
-#include <asm/uaccess.h>
-#include <asm/system.h>
-#include <asm/io.h>
-#include <asm/processor.h>
-#include <asm/mmu.h>
-#include <asm/mmu_context.h>
-#include <asm/prom.h>
-#include <asm/ppcdebug.h>
-#include <asm/machdep.h>
-#include <asm/iSeries/HvCallHpt.h>
-#include <asm/cputable.h>
-#include <asm/firmware.h>
-#include <asm/sections.h>
-#include <asm/tlbflush.h>
-#include <asm/time.h>
-#include <asm/plpar_wrappers.h>
-
-#ifndef CONFIG_SMP
-struct task_struct *last_task_used_math = NULL;
-struct task_struct *last_task_used_altivec = NULL;
-#endif
-
-/*
- * Make sure the floating-point register state in the
- * the thread_struct is up to date for task tsk.
- */
-void flush_fp_to_thread(struct task_struct *tsk)
-{
- if (tsk->thread.regs) {
- /*
- * We need to disable preemption here because if we didn't,
- * another process could get scheduled after the regs->msr
- * test but before we have finished saving the FP registers
- * to the thread_struct. That process could take over the
- * FPU, and then when we get scheduled again we would store
- * bogus values for the remaining FP registers.
- */
- preempt_disable();
- if (tsk->thread.regs->msr & MSR_FP) {
-#ifdef CONFIG_SMP
- /*
- * This should only ever be called for current or
- * for a stopped child process. Since we save away
- * the FP register state on context switch on SMP,
- * there is something wrong if a stopped child appears
- * to still have its FP state in the CPU registers.
- */
- BUG_ON(tsk != current);
-#endif
- giveup_fpu(current);
- }
- preempt_enable();
- }
-}
-
-void enable_kernel_fp(void)
-{
- WARN_ON(preemptible());
-
-#ifdef CONFIG_SMP
- if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
- giveup_fpu(current);
- else
- giveup_fpu(NULL); /* just enables FP for kernel */
-#else
- giveup_fpu(last_task_used_math);
-#endif /* CONFIG_SMP */
-}
-EXPORT_SYMBOL(enable_kernel_fp);
-
-int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
-{
- if (!tsk->thread.regs)
- return 0;
- flush_fp_to_thread(current);
-
- memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs));
-
- return 1;
-}
-
-#ifdef CONFIG_ALTIVEC
-
-void enable_kernel_altivec(void)
-{
- WARN_ON(preemptible());
-
-#ifdef CONFIG_SMP
- if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
- giveup_altivec(current);
- else
- giveup_altivec(NULL); /* just enables FP for kernel */
-#else
- giveup_altivec(last_task_used_altivec);
-#endif /* CONFIG_SMP */
-}
-EXPORT_SYMBOL(enable_kernel_altivec);
-
-/*
- * Make sure the VMX/Altivec register state in the
- * the thread_struct is up to date for task tsk.
- */
-void flush_altivec_to_thread(struct task_struct *tsk)
-{
- if (tsk->thread.regs) {
- preempt_disable();
- if (tsk->thread.regs->msr & MSR_VEC) {
-#ifdef CONFIG_SMP
- BUG_ON(tsk != current);
-#endif
- giveup_altivec(current);
- }
- preempt_enable();
- }
-}
-
-int dump_task_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs)
-{
- flush_altivec_to_thread(current);
- memcpy(vrregs, ¤t->thread.vr[0], sizeof(*vrregs));
- return 1;
-}
-
-#endif /* CONFIG_ALTIVEC */
-
-static void set_dabr_spr(unsigned long val)
-{
- mtspr(SPRN_DABR, val);
-}
-
-int set_dabr(unsigned long dabr)
-{
- int ret = 0;
-
- if (firmware_has_feature(FW_FEATURE_XDABR)) {
- /* We want to catch accesses from kernel and userspace */
- unsigned long flags = H_DABRX_KERNEL|H_DABRX_USER;
- ret = plpar_set_xdabr(dabr, flags);
- } else if (firmware_has_feature(FW_FEATURE_DABR)) {
- ret = plpar_set_dabr(dabr);
- } else {
- set_dabr_spr(dabr);
- }
-
- return ret;
-}
-
-DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
-static DEFINE_PER_CPU(unsigned long, current_dabr);
-
-struct task_struct *__switch_to(struct task_struct *prev,
- struct task_struct *new)
-{
- struct thread_struct *new_thread, *old_thread;
- unsigned long flags;
- struct task_struct *last;
-
-#ifdef CONFIG_SMP
- /* avoid complexity of lazy save/restore of fpu
- * by just saving it every time we switch out if
- * this task used the fpu during the last quantum.
- *
- * If it tries to use the fpu again, it'll trap and
- * reload its fp regs. So we don't have to do a restore
- * every switch, just a save.
- * -- Cort
- */
- if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP))
- giveup_fpu(prev);
-#ifdef CONFIG_ALTIVEC
- if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))
- giveup_altivec(prev);
-#endif /* CONFIG_ALTIVEC */
-#endif /* CONFIG_SMP */
-
-#if defined(CONFIG_ALTIVEC) && !defined(CONFIG_SMP)
- /* Avoid the trap. On smp this this never happens since
- * we don't set last_task_used_altivec -- Cort
- */
- if (new->thread.regs && last_task_used_altivec == new)
- new->thread.regs->msr |= MSR_VEC;
-#endif /* CONFIG_ALTIVEC */
-
- if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) {
- set_dabr(new->thread.dabr);
- __get_cpu_var(current_dabr) = new->thread.dabr;
- }
-
- flush_tlb_pending();
-
- new_thread = &new->thread;
- old_thread = ¤t->thread;
-
- /* Collect purr utilization data per process and per processor
- * wise purr is nothing but processor time base
- */
- if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
- struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
- long unsigned start_tb, current_tb;
- start_tb = old_thread->start_tb;
- cu->current_tb = current_tb = mfspr(SPRN_PURR);
- old_thread->accum_tb += (current_tb - start_tb);
- new_thread->start_tb = current_tb;
- }
-
- local_irq_save(flags);
- last = _switch(old_thread, new_thread);
-
- local_irq_restore(flags);
-
- return last;
-}
-
-static int instructions_to_print = 16;
-
-static void show_instructions(struct pt_regs *regs)
-{
- int i;
- unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
- sizeof(int));
-
- printk("Instruction dump:");
-
- for (i = 0; i < instructions_to_print; i++) {
- int instr;
-
- if (!(i % 8))
- printk("\n");
-
- if (((REGION_ID(pc) != KERNEL_REGION_ID) &&
- (REGION_ID(pc) != VMALLOC_REGION_ID)) ||
- __get_user(instr, (unsigned int *)pc)) {
- printk("XXXXXXXX ");
- } else {
- if (regs->nip == pc)
- printk("<%08x> ", instr);
- else
- printk("%08x ", instr);
- }
-
- pc += sizeof(int);
- }
-
- printk("\n");
-}
-
-void show_regs(struct pt_regs * regs)
-{
- int i;
- unsigned long trap;
-
- printk("NIP: %016lX XER: %08X LR: %016lX CTR: %016lX\n",
- regs->nip, (unsigned int)regs->xer, regs->link, regs->ctr);
- printk("REGS: %p TRAP: %04lx %s (%s)\n",
- regs, regs->trap, print_tainted(), system_utsname.release);
- printk("MSR: %016lx EE: %01x PR: %01x FP: %01x ME: %01x "
- "IR/DR: %01x%01x CR: %08X\n",
- regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
- regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
- regs->msr&MSR_IR ? 1 : 0,
- regs->msr&MSR_DR ? 1 : 0,
- (unsigned int)regs->ccr);
- trap = TRAP(regs);
- printk("DAR: %016lx DSISR: %016lx\n", regs->dar, regs->dsisr);
- printk("TASK: %p[%d] '%s' THREAD: %p",
- current, current->pid, current->comm, current->thread_info);
-
-#ifdef CONFIG_SMP
- printk(" CPU: %d", smp_processor_id());
-#endif /* CONFIG_SMP */
-
- for (i = 0; i < 32; i++) {
- if ((i % 4) == 0) {
- printk("\n" KERN_INFO "GPR%02d: ", i);
- }
-
- printk("%016lX ", regs->gpr[i]);
- if (i == 13 && !FULL_REGS(regs))
- break;
- }
- printk("\n");
- /*
- * Lookup NIP late so we have the best change of getting the
- * above info out without failing
- */
- printk("NIP [%016lx] ", regs->nip);
- print_symbol("%s\n", regs->nip);
- printk("LR [%016lx] ", regs->link);
- print_symbol("%s\n", regs->link);
- show_stack(current, (unsigned long *)regs->gpr[1]);
- if (!user_mode(regs))
- show_instructions(regs);
-}
-
-void exit_thread(void)
-{
- kprobe_flush_task(current);
-
-#ifndef CONFIG_SMP
- if (last_task_used_math == current)
- last_task_used_math = NULL;
-#ifdef CONFIG_ALTIVEC
- if (last_task_used_altivec == current)
- last_task_used_altivec = NULL;
-#endif /* CONFIG_ALTIVEC */
-#endif /* CONFIG_SMP */
-}
-
-void flush_thread(void)
-{
- struct thread_info *t = current_thread_info();
-
- kprobe_flush_task(current);
- if (t->flags & _TIF_ABI_PENDING)
- t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);
-
-#ifndef CONFIG_SMP
- if (last_task_used_math == current)
- last_task_used_math = NULL;
-#ifdef CONFIG_ALTIVEC
- if (last_task_used_altivec == current)
- last_task_used_altivec = NULL;
-#endif /* CONFIG_ALTIVEC */
-#endif /* CONFIG_SMP */
-
- if (current->thread.dabr) {
- current->thread.dabr = 0;
- set_dabr(0);
- }
-}
-
-void
-release_thread(struct task_struct *t)
-{
-}
-
-
-/*
- * This gets called before we allocate a new thread and copy
- * the current task into it.
- */
-void prepare_to_copy(struct task_struct *tsk)
-{
- flush_fp_to_thread(current);
- flush_altivec_to_thread(current);
-}
-
-/*
- * Copy a thread..
- */
-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, *kregs;
- extern void ret_from_fork(void);
- unsigned long sp = (unsigned long)p->thread_info + THREAD_SIZE;
-
- /* Copy registers */
- sp -= sizeof(struct pt_regs);
- childregs = (struct pt_regs *) sp;
- *childregs = *regs;
- if ((childregs->msr & MSR_PR) == 0) {
- /* for kernel thread, set stackptr in new task */
- childregs->gpr[1] = sp + sizeof(struct pt_regs);
- p->thread.regs = NULL; /* no user register state */
- clear_ti_thread_flag(p->thread_info, TIF_32BIT);
- } else {
- childregs->gpr[1] = usp;
- p->thread.regs = childregs;
- if (clone_flags & CLONE_SETTLS) {
- if (test_thread_flag(TIF_32BIT))
- childregs->gpr[2] = childregs->gpr[6];
- else
- childregs->gpr[13] = childregs->gpr[6];
- }
- }
- childregs->gpr[3] = 0; /* Result from fork() */
- sp -= STACK_FRAME_OVERHEAD;
-
- /*
- * The way this works is that at some point in the future
- * some task will call _switch to switch to the new task.
- * That will pop off the stack frame created below and start
- * the new task running at ret_from_fork. The new task will
- * do some house keeping and then return from the fork or clone
- * system call, using the stack frame created above.
- */
- sp -= sizeof(struct pt_regs);
- kregs = (struct pt_regs *) sp;
- sp -= STACK_FRAME_OVERHEAD;
- p->thread.ksp = sp;
- if (cpu_has_feature(CPU_FTR_SLB)) {
- unsigned long sp_vsid = get_kernel_vsid(sp);
-
- sp_vsid <<= SLB_VSID_SHIFT;
- sp_vsid |= SLB_VSID_KERNEL;
- if (cpu_has_feature(CPU_FTR_16M_PAGE))
- sp_vsid |= SLB_VSID_L;
-
- p->thread.ksp_vsid = sp_vsid;
- }
-
- /*
- * The PPC64 ABI makes use of a TOC to contain function
- * pointers. The function (ret_from_except) is actually a pointer
- * to the TOC entry. The first entry is a pointer to the actual
- * function.
- */
- kregs->nip = *((unsigned long *)ret_from_fork);
-
- return 0;
-}
-
-/*
- * Set up a thread for executing a new program
- */
-void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp)
-{
- unsigned long entry, toc, load_addr = regs->gpr[2];
-
- /* fdptr is a relocated pointer to the function descriptor for
- * the elf _start routine. The first entry in the function
- * descriptor is the entry address of _start and the second
- * entry is the TOC value we need to use.
- */
- set_fs(USER_DS);
- __get_user(entry, (unsigned long __user *)fdptr);
- __get_user(toc, (unsigned long __user *)fdptr+1);
-
- /* Check whether the e_entry function descriptor entries
- * need to be relocated before we can use them.
- */
- if (load_addr != 0) {
- entry += load_addr;
- toc += load_addr;
- }
-
- /*
- * If we exec out of a kernel thread then thread.regs will not be
- * set. Do it now.
- */
- if (!current->thread.regs) {
- unsigned long childregs = (unsigned long)current->thread_info +
- THREAD_SIZE;
- childregs -= sizeof(struct pt_regs);
- current->thread.regs = (struct pt_regs *)childregs;
- }
-
- regs->nip = entry;
- regs->gpr[1] = sp;
- regs->gpr[2] = toc;
- regs->msr = MSR_USER64;
-#ifndef CONFIG_SMP
- if (last_task_used_math == current)
- last_task_used_math = 0;
-#endif /* CONFIG_SMP */
- memset(current->thread.fpr, 0, sizeof(current->thread.fpr));
- current->thread.fpscr = 0;
-#ifdef CONFIG_ALTIVEC
-#ifndef CONFIG_SMP
- if (last_task_used_altivec == current)
- last_task_used_altivec = 0;
-#endif /* CONFIG_SMP */
- memset(current->thread.vr, 0, sizeof(current->thread.vr));
- current->thread.vscr.u[0] = 0;
- current->thread.vscr.u[1] = 0;
- current->thread.vscr.u[2] = 0;
- current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */
- current->thread.vrsave = 0;
- current->thread.used_vr = 0;
-#endif /* CONFIG_ALTIVEC */
-}
-EXPORT_SYMBOL(start_thread);
-
-int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
-{
- struct pt_regs *regs = tsk->thread.regs;
-
- if (val > PR_FP_EXC_PRECISE)
- return -EINVAL;
- tsk->thread.fpexc_mode = __pack_fe01(val);
- if (regs != NULL && (regs->msr & MSR_FP) != 0)
- regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
- | tsk->thread.fpexc_mode;
- return 0;
-}
-
-int get_fpexc_mode(struct task_struct *tsk, unsigned long adr)
-{
- unsigned int val;
-
- val = __unpack_fe01(tsk->thread.fpexc_mode);
- return put_user(val, (unsigned int __user *) adr);
-}
-
-int sys_clone(unsigned long clone_flags, unsigned long p2, unsigned long p3,
- unsigned long p4, unsigned long p5, unsigned long p6,
- struct pt_regs *regs)
-{
- unsigned long parent_tidptr = 0;
- unsigned long child_tidptr = 0;
-
- if (p2 == 0)
- p2 = regs->gpr[1]; /* stack pointer for child */
-
- if (clone_flags & (CLONE_PARENT_SETTID | CLONE_CHILD_SETTID |
- CLONE_CHILD_CLEARTID)) {
- parent_tidptr = p3;
- child_tidptr = p5;
- if (test_thread_flag(TIF_32BIT)) {
- parent_tidptr &= 0xffffffff;
- child_tidptr &= 0xffffffff;
- }
- }
-
- return do_fork(clone_flags, p2, regs, 0,
- (int __user *)parent_tidptr, (int __user *)child_tidptr);
-}
-
-int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3,
- unsigned long p4, unsigned long p5, unsigned long p6,
- struct pt_regs *regs)
-{
- return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL);
-}
-
-int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3,
- unsigned long p4, unsigned long p5, unsigned long p6,
- struct pt_regs *regs)
-{
- return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1], regs, 0,
- NULL, NULL);
-}
-
-int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
- unsigned long a3, unsigned long a4, unsigned long a5,
- struct pt_regs *regs)
-{
- int error;
- char * filename;
-
- filename = getname((char __user *) a0);
- error = PTR_ERR(filename);
- if (IS_ERR(filename))
- goto out;
- flush_fp_to_thread(current);
- flush_altivec_to_thread(current);
- error = do_execve(filename, (char __user * __user *) a1,
- (char __user * __user *) a2, regs);
-
- if (error == 0) {
- task_lock(current);
- current->ptrace &= ~PT_DTRACE;
- task_unlock(current);
- }
- putname(filename);
-
-out:
- return error;
-}
-
-static int kstack_depth_to_print = 64;
-
-static int validate_sp(unsigned long sp, struct task_struct *p,
- unsigned long nbytes)
-{
- unsigned long stack_page = (unsigned long)p->thread_info;
-
- if (sp >= stack_page + sizeof(struct thread_struct)
- && sp <= stack_page + THREAD_SIZE - nbytes)
- return 1;
-
-#ifdef CONFIG_IRQSTACKS
- stack_page = (unsigned long) hardirq_ctx[task_cpu(p)];
- if (sp >= stack_page + sizeof(struct thread_struct)
- && sp <= stack_page + THREAD_SIZE - nbytes)
- return 1;
-
- stack_page = (unsigned long) softirq_ctx[task_cpu(p)];
- if (sp >= stack_page + sizeof(struct thread_struct)
- && sp <= stack_page + THREAD_SIZE - nbytes)
- return 1;
-#endif
-
- return 0;
-}
-
-unsigned long get_wchan(struct task_struct *p)
-{
- unsigned long ip, sp;
- int count = 0;
-
- if (!p || p == current || p->state == TASK_RUNNING)
- return 0;
-
- sp = p->thread.ksp;
- if (!validate_sp(sp, p, 112))
- return 0;
-
- do {
- sp = *(unsigned long *)sp;
- if (!validate_sp(sp, p, 112))
- return 0;
- if (count > 0) {
- ip = *(unsigned long *)(sp + 16);
- if (!in_sched_functions(ip))
- return ip;
- }
- } while (count++ < 16);
- return 0;
-}
-EXPORT_SYMBOL(get_wchan);
-
-void show_stack(struct task_struct *p, unsigned long *_sp)
-{
- unsigned long ip, newsp, lr;
- int count = 0;
- unsigned long sp = (unsigned long)_sp;
- int firstframe = 1;
-
- if (sp == 0) {
- if (p) {
- sp = p->thread.ksp;
- } else {
- sp = __get_SP();
- p = current;
- }
- }
-
- lr = 0;
- printk("Call Trace:\n");
- do {
- if (!validate_sp(sp, p, 112))
- return;
-
- _sp = (unsigned long *) sp;
- newsp = _sp[0];
- ip = _sp[2];
- if (!firstframe || ip != lr) {
- printk("[%016lx] [%016lx] ", sp, ip);
- print_symbol("%s", ip);
- if (firstframe)
- printk(" (unreliable)");
- printk("\n");
- }
- firstframe = 0;
-
- /*
- * See if this is an exception frame.
- * We look for the "regshere" marker in the current frame.
- */
- if (validate_sp(sp, p, sizeof(struct pt_regs) + 400)
- && _sp[12] == 0x7265677368657265ul) {
- struct pt_regs *regs = (struct pt_regs *)
- (sp + STACK_FRAME_OVERHEAD);
- printk("--- Exception: %lx", regs->trap);
- print_symbol(" at %s\n", regs->nip);
- lr = regs->link;
- print_symbol(" LR = %s\n", lr);
- firstframe = 1;
- }
-
- sp = newsp;
- } while (count++ < kstack_depth_to_print);
-}
-
-void dump_stack(void)
-{
- show_stack(current, (unsigned long *)__get_SP());
-}
-EXPORT_SYMBOL(dump_stack);
git.openpandora.org / pandora-kernel.git / commitdiff