/* * arch/ppc/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/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/ptrace.h>#include <linux/slab.h>#include <linux/user.h>#include <linux/elf.h>#include <linux/init.h>#include <linux/prctl.h>#include <linux/init_task.h>#include <linux/module.h>#include <linux/kallsyms.h>#include <linux/mqueue.h>#include <linux/hardirq.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/prom.h> extern unsigned long _get_SP(void); struct task_struct *last_task_used_math = NULL;struct task_struct *last_task_used_altivec = NULL;struct task_struct *last_task_used_spe = NULL; 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); /* this is 8kB-aligned so we can get to the thread_info struct at the base of it from the stack pointer with 1 integer instruction. */union thread_union init_thread_union __attribute__((__section__(".data.init_task"))) ={ INIT_THREAD_INFO(init_task) }; /* initial task structure */struct task_struct init_task = INIT_TASK(init_task);EXPORT_SYMBOL(init_task); /* only used to get secondary processor up */struct task_struct *current_set[NR_CPUS] = {&init_task, }; #undef SHOW_TASK_SWITCHES#undef CHECK_STACK #if defined(CHECK_STACK)unsigned longkernel_stack_top(struct task_struct *tsk){ return ((unsigned long)tsk) + sizeof(union task_union);} unsigned longtask_top(struct task_struct *tsk){ return ((unsigned long)tsk) + sizeof(struct thread_info);} /* check to make sure the kernel stack is healthy */int check_stack(struct task_struct *tsk){ unsigned long stack_top = kernel_stack_top(tsk); unsigned long tsk_top = task_top(tsk); int ret = 0; #if 0 /* check thread magic */ if ( tsk->thread.magic != THREAD_MAGIC ) { ret |= 1; printk("thread.magic bad: %08x\n", tsk->thread.magic); }#endif if ( !tsk ) printk("check_stack(): tsk bad tsk %p\n",tsk); /* check if stored ksp is bad */ if ( (tsk->thread.ksp > stack_top) || (tsk->thread.ksp < tsk_top) ) { printk("stack out of bounds: %s/%d\n" " tsk_top %08lx ksp %08lx stack_top %08lx\n", tsk->comm,tsk->pid, tsk_top, tsk->thread.ksp, stack_top); ret |= 2; } /* check if stack ptr RIGHT NOW is bad */ if ( (tsk == current) && ((_get_SP() > stack_top ) || (_get_SP() < tsk_top)) ) { printk("current stack ptr out of bounds: %s/%d\n" " tsk_top %08lx sp %08lx stack_top %08lx\n", current->comm,current->pid, tsk_top, _get_SP(), stack_top); ret |= 4; } #if 0 /* check amount of free stack */ for ( i = (unsigned long *)task_top(tsk) ; i < kernel_stack_top(tsk) ; i++ ) { if ( !i ) printk("check_stack(): i = %p\n", i); if ( *i != 0 ) { /* only notify if it's less than 900 bytes */ if ( (i - (unsigned long *)task_top(tsk)) < 900 ) printk("%d bytes free on stack\n", i - task_top(tsk)); break; } }#endif if (ret) { panic("bad kernel stack"); } return(ret);}#endif /* defined(CHECK_STACK) */ #ifdef CONFIG_ALTIVECintdump_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs){ if (regs->msr & MSR_VEC) giveup_altivec(current); memcpy(vrregs, ¤t->thread.vr[0], sizeof(*vrregs)); return 1;} voidenable_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 enable AltiVec for kernel - force */#else giveup_altivec(last_task_used_altivec);#endif /* __SMP __ */}EXPORT_SYMBOL(enable_kernel_altivec);#endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPEintdump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs){ if (regs->msr & MSR_SPE) giveup_spe(current); /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */ memcpy(evrregs, ¤t->thread.evr[0], sizeof(u32) * 35); return 1;} voidenable_kernel_spe(void){ WARN_ON(preemptible()); #ifdef CONFIG_SMP if (current->thread.regs && (current->thread.regs->msr & MSR_SPE)) giveup_spe(current); else giveup_spe(NULL); /* just enable SPE for kernel - force */#else giveup_spe(last_task_used_spe);#endif /* __SMP __ */}EXPORT_SYMBOL(enable_kernel_spe);#endif /* CONFIG_SPE */ voidenable_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); intdump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs){ preempt_disable(); if (tsk->thread.regs && (tsk->thread.regs->msr & MSR_FP)) giveup_fpu(tsk); preempt_enable(); memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs)); return 1;} struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *new){ struct thread_struct *new_thread, *old_thread; unsigned long s; struct task_struct *last; local_irq_save(s);#ifdef CHECK_STACK check_stack(prev); check_stack(new);#endif #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 the previous thread used altivec in the last quantum * (thus changing altivec regs) then save them. * We used to check the VRSAVE register but not all apps * set it, so we don't rely on it now (and in fact we need * to save & restore VSCR even if VRSAVE == 0). -- paulus * * On SMP we always save/restore altivec regs just to avoid the * complexity of changing processors. * -- Cort */ if ((prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))) giveup_altivec(prev);#endif /* CONFIG_ALTIVEC */#ifdef CONFIG_SPE /* * If the previous thread used spe in the last quantum * (thus changing spe regs) then save them. * * On SMP we always save/restore spe regs just to avoid the * complexity of changing processors. */ if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE))) giveup_spe(prev);#endif /* CONFIG_SPE */#endif /* 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;#ifdef CONFIG_SPE /* Avoid the trap. On smp this this never happens since * we don't set last_task_used_spe */ if (new->thread.regs && last_task_used_spe == new) new->thread.regs->msr |= MSR_SPE;#endif /* CONFIG_SPE */ new_thread = &new->thread; old_thread = ¤t->thread; last = _switch(old_thread, new_thread); local_irq_restore(s); return last;} void show_regs(struct pt_regs * regs){ int i, trap; printk("NIP: %08lX LR: %08lX SP: %08lX REGS: %p TRAP: %04lx %s\n", regs->nip, regs->link, regs->gpr[1], regs, regs->trap, print_tainted()); printk("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\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); trap = TRAP(regs); if (trap == 0x300 || trap == 0x600) printk("DAR: %08lX, DSISR: %08lX\n", regs->dar, regs->dsisr); printk("TASK = %p[%d] '%s' THREAD: %p\n", current, current->pid, current->comm, current->thread_info); printk("Last syscall: %ld ", current->thread.last_syscall); #ifdef CONFIG_SMP printk(" CPU: %d", smp_processor_id());#endif /* CONFIG_SMP */ for (i = 0; i < 32; i++) { long r; if ((i % 8) == 0) printk("\n" KERN_INFO "GPR%02d: ", i); if (__get_user(r, ®s->gpr[i])) break; printk("%08lX ", r); if (i == 12 && !FULL_REGS(regs)) break; } printk("\n");#ifdef CONFIG_KALLSYMS /* * Lookup NIP late so we have the best change of getting the * above info out without failing */ printk("NIP [%08lx] ", regs->nip); print_symbol("%s\n", regs->nip); printk("LR [%08lx] ", regs->link); print_symbol("%s\n", regs->link);#endif show_stack(current, (unsigned long *) regs->gpr[1]);} void exit_thread(void){ if (last_task_used_math == current) last_task_used_math = NULL; if (last_task_used_altivec == current) last_task_used_altivec = NULL;#ifdef CONFIG_SPE if (last_task_used_spe == current) last_task_used_spe = NULL;#endif} void flush_thread(void){ if (last_task_used_math == current) last_task_used_math = NULL; if (last_task_used_altivec == current) last_task_used_altivec = NULL;#ifdef CONFIG_SPE if (last_task_used_spe == current) last_task_used_spe = NULL;#endif} voidrelease_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){ struct pt_regs *regs = tsk->thread.regs; if (regs == NULL) return; preempt_disable(); if (regs->msr & MSR_FP) giveup_fpu(current);#ifdef CONFIG_ALTIVEC if (regs->msr & MSR_VEC) giveup_altivec(current);#endif /* CONFIG_ALTIVEC */#ifdef CONFIG_SPE if (regs->msr & MSR_SPE) giveup_spe(current);#endif /* CONFIG_SPE */ preempt_enable();} /* * Copy a thread.. */intcopy_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; unsigned long childframe; CHECK_FULL_REGS(regs); /* Copy registers */ sp -= sizeof(struct pt_regs); childregs = (struct pt_regs *) sp; *childregs = *regs; if ((childregs->msr & MSR_PR) == 0) { /* for kernel thread, set `current' and stackptr in new task */ childregs->gpr[1] = sp + sizeof(struct pt_regs); childregs->gpr[2] = (unsigned long) p; p->thread.regs = NULL; /* no user register state */ } else { childregs->gpr[1] = usp; p->thread.regs = childregs; if (clone_flags & CLONE_SETTLS) childregs->gpr[2] = childregs->gpr[6]; } childregs->gpr[3] = 0; /* Result from fork() */ sp -= STACK_FRAME_OVERHEAD; childframe = sp; /* * 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; kregs->nip = (unsigned long)ret_from_fork; p->thread.last_syscall = -1; return 0;} /* * Set up a thread for executing a new program */void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp){ set_fs(USER_DS); memset(regs->gpr, 0, sizeof(regs->gpr)); regs->ctr = 0; regs->link = 0; regs->xer = 0; regs->ccr = 0; regs->mq = 0; regs->nip = nip; regs->gpr[1] = sp; regs->msr = MSR_USER; if (last_task_used_math == current) last_task_used_math = NULL; if (last_task_used_altivec == current) last_task_used_altivec = NULL;#ifdef CONFIG_SPE if (last_task_used_spe == current) last_task_used_spe = NULL;#endif memset(current->thread.fpr, 0, sizeof(current->thread.fpr)); current->thread.fpscr = 0;#ifdef CONFIG_ALTIVEC memset(current->thread.vr, 0, sizeof(current->thread.vr)); memset(¤t->thread.vscr, 0, sizeof(current->thread.vscr)); current->thread.vrsave = 0; current->thread.used_vr = 0;#endif /* CONFIG_ALTIVEC */#ifdef CONFIG_SPE memset(current->thread.evr, 0, sizeof(current->thread.evr)); current->thread.acc = 0; current->thread.spefscr = 0; current->thread.used_spe = 0;#endif /* CONFIG_SPE */} #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \Lines 1–500 of 781. 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/* * arch/ppc/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/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/ptrace.h> #include <linux/slab.h> #include <linux/user.h> #include <linux/elf.h> #include <linux/init.h> #include <linux/prctl.h> #include <linux/init_task.h> #include <linux/module.h> #include <linux/kallsyms.h> #include <linux/mqueue.h> #include <linux/hardirq.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/prom.h> extern unsigned long _get_SP(void); struct task_struct *last_task_used_math = NULL; struct task_struct *last_task_used_altivec = NULL; struct task_struct *last_task_used_spe = NULL; 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); /* this is 8kB-aligned so we can get to the thread_info struct at the base of it from the stack pointer with 1 integer instruction. */ union thread_union init_thread_union __attribute__((__section__(".data.init_task"))) = { INIT_THREAD_INFO(init_task) }; /* initial task structure */ struct task_struct init_task = INIT_TASK(init_task); EXPORT_SYMBOL(init_task); /* only used to get secondary processor up */ struct task_struct *current_set[NR_CPUS] = {&init_task, }; #undef SHOW_TASK_SWITCHES #undef CHECK_STACK #if defined(CHECK_STACK) unsigned long kernel_stack_top(struct task_struct *tsk) { return ((unsigned long)tsk) + sizeof(union task_union); } unsigned long task_top(struct task_struct *tsk) { return ((unsigned long)tsk) + sizeof(struct thread_info); } /* check to make sure the kernel stack is healthy */ int check_stack(struct task_struct *tsk) { unsigned long stack_top = kernel_stack_top(tsk); unsigned long tsk_top = task_top(tsk); int ret = 0; #if 0 /* check thread magic */ if ( tsk->thread.magic != THREAD_MAGIC ) { ret |= 1; printk("thread.magic bad: %08x\n", tsk->thread.magic); } #endif if ( !tsk ) printk("check_stack(): tsk bad tsk %p\n",tsk); /* check if stored ksp is bad */ if ( (tsk->thread.ksp > stack_top) || (tsk->thread.ksp < tsk_top) ) { printk("stack out of bounds: %s/%d\n" " tsk_top %08lx ksp %08lx stack_top %08lx\n", tsk->comm,tsk->pid, tsk_top, tsk->thread.ksp, stack_top); ret |= 2; } /* check if stack ptr RIGHT NOW is bad */ if ( (tsk == current) && ((_get_SP() > stack_top ) || (_get_SP() < tsk_top)) ) { printk("current stack ptr out of bounds: %s/%d\n" " tsk_top %08lx sp %08lx stack_top %08lx\n", current->comm,current->pid, tsk_top, _get_SP(), stack_top); ret |= 4; } #if 0 /* check amount of free stack */ for ( i = (unsigned long *)task_top(tsk) ; i < kernel_stack_top(tsk) ; i++ ) { if ( !i ) printk("check_stack(): i = %p\n", i); if ( *i != 0 ) { /* only notify if it's less than 900 bytes */ if ( (i - (unsigned long *)task_top(tsk)) < 900 ) printk("%d bytes free on stack\n", i - task_top(tsk)); break; } } #endif if (ret) { panic("bad kernel stack"); } return(ret); } #endif /* defined(CHECK_STACK) */ #ifdef CONFIG_ALTIVEC int dump_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs) { if (regs->msr & MSR_VEC) giveup_altivec(current); memcpy(vrregs, ¤t->thread.vr[0], sizeof(*vrregs)); return 1; } 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 enable AltiVec for kernel - force */ #else giveup_altivec(last_task_used_altivec); #endif /* __SMP __ */ } EXPORT_SYMBOL(enable_kernel_altivec); #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE int dump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs) { if (regs->msr & MSR_SPE) giveup_spe(current); /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */ memcpy(evrregs, ¤t->thread.evr[0], sizeof(u32) * 35); return 1; } void enable_kernel_spe(void) { WARN_ON(preemptible()); #ifdef CONFIG_SMP if (current->thread.regs && (current->thread.regs->msr & MSR_SPE)) giveup_spe(current); else giveup_spe(NULL); /* just enable SPE for kernel - force */ #else giveup_spe(last_task_used_spe); #endif /* __SMP __ */ } EXPORT_SYMBOL(enable_kernel_spe); #endif /* CONFIG_SPE */ 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) { preempt_disable(); if (tsk->thread.regs && (tsk->thread.regs->msr & MSR_FP)) giveup_fpu(tsk); preempt_enable(); memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs)); return 1; } struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *new) { struct thread_struct *new_thread, *old_thread; unsigned long s; struct task_struct *last; local_irq_save(s); #ifdef CHECK_STACK check_stack(prev); check_stack(new); #endif #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 the previous thread used altivec in the last quantum * (thus changing altivec regs) then save them. * We used to check the VRSAVE register but not all apps * set it, so we don't rely on it now (and in fact we need * to save & restore VSCR even if VRSAVE == 0). -- paulus * * On SMP we always save/restore altivec regs just to avoid the * complexity of changing processors. * -- Cort */ if ((prev->thread.regs && (prev->thread.regs->msr & MSR_VEC))) giveup_altivec(prev); #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE /* * If the previous thread used spe in the last quantum * (thus changing spe regs) then save them. * * On SMP we always save/restore spe regs just to avoid the * complexity of changing processors. */ if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE))) giveup_spe(prev); #endif /* CONFIG_SPE */ #endif /* 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; #ifdef CONFIG_SPE /* Avoid the trap. On smp this this never happens since * we don't set last_task_used_spe */ if (new->thread.regs && last_task_used_spe == new) new->thread.regs->msr |= MSR_SPE; #endif /* CONFIG_SPE */ new_thread = &new->thread; old_thread = ¤t->thread; last = _switch(old_thread, new_thread); local_irq_restore(s); return last; } void show_regs(struct pt_regs * regs) { int i, trap; printk("NIP: %08lX LR: %08lX SP: %08lX REGS: %p TRAP: %04lx %s\n", regs->nip, regs->link, regs->gpr[1], regs, regs->trap, print_tainted()); printk("MSR: %08lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\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); trap = TRAP(regs); if (trap == 0x300 || trap == 0x600) printk("DAR: %08lX, DSISR: %08lX\n", regs->dar, regs->dsisr); printk("TASK = %p[%d] '%s' THREAD: %p\n", current, current->pid, current->comm, current->thread_info); printk("Last syscall: %ld ", current->thread.last_syscall); #ifdef CONFIG_SMP printk(" CPU: %d", smp_processor_id()); #endif /* CONFIG_SMP */ for (i = 0; i < 32; i++) { long r; if ((i % 8) == 0) printk("\n" KERN_INFO "GPR%02d: ", i); if (__get_user(r, ®s->gpr[i])) break; printk("%08lX ", r); if (i == 12 && !FULL_REGS(regs)) break; } printk("\n"); #ifdef CONFIG_KALLSYMS /* * Lookup NIP late so we have the best change of getting the * above info out without failing */ printk("NIP [%08lx] ", regs->nip); print_symbol("%s\n", regs->nip); printk("LR [%08lx] ", regs->link); print_symbol("%s\n", regs->link); #endif show_stack(current, (unsigned long *) regs->gpr[1]); } void exit_thread(void) { if (last_task_used_math == current) last_task_used_math = NULL; if (last_task_used_altivec == current) last_task_used_altivec = NULL; #ifdef CONFIG_SPE if (last_task_used_spe == current) last_task_used_spe = NULL; #endif } void flush_thread(void) { if (last_task_used_math == current) last_task_used_math = NULL; if (last_task_used_altivec == current) last_task_used_altivec = NULL; #ifdef CONFIG_SPE if (last_task_used_spe == current) last_task_used_spe = NULL; #endif } 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) { struct pt_regs *regs = tsk->thread.regs; if (regs == NULL) return; preempt_disable(); if (regs->msr & MSR_FP) giveup_fpu(current); #ifdef CONFIG_ALTIVEC if (regs->msr & MSR_VEC) giveup_altivec(current); #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE if (regs->msr & MSR_SPE) giveup_spe(current); #endif /* CONFIG_SPE */ preempt_enable(); } /* * 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; unsigned long childframe; CHECK_FULL_REGS(regs); /* Copy registers */ sp -= sizeof(struct pt_regs); childregs = (struct pt_regs *) sp; *childregs = *regs; if ((childregs->msr & MSR_PR) == 0) { /* for kernel thread, set `current' and stackptr in new task */ childregs->gpr[1] = sp + sizeof(struct pt_regs); childregs->gpr[2] = (unsigned long) p; p->thread.regs = NULL; /* no user register state */ } else { childregs->gpr[1] = usp; p->thread.regs = childregs; if (clone_flags & CLONE_SETTLS) childregs->gpr[2] = childregs->gpr[6]; } childregs->gpr[3] = 0; /* Result from fork() */ sp -= STACK_FRAME_OVERHEAD; childframe = sp; /* * 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; kregs->nip = (unsigned long)ret_from_fork; p->thread.last_syscall = -1; return 0; } /* * Set up a thread for executing a new program */ void start_thread(struct pt_regs *regs, unsigned long nip, unsigned long sp) { set_fs(USER_DS); memset(regs->gpr, 0, sizeof(regs->gpr)); regs->ctr = 0; regs->link = 0; regs->xer = 0; regs->ccr = 0; regs->mq = 0; regs->nip = nip; regs->gpr[1] = sp; regs->msr = MSR_USER; if (last_task_used_math == current) last_task_used_math = NULL; if (last_task_used_altivec == current) last_task_used_altivec = NULL; #ifdef CONFIG_SPE if (last_task_used_spe == current) last_task_used_spe = NULL; #endif memset(current->thread.fpr, 0, sizeof(current->thread.fpr)); current->thread.fpscr = 0; #ifdef CONFIG_ALTIVEC memset(current->thread.vr, 0, sizeof(current->thread.vr)); memset(¤t->thread.vscr, 0, sizeof(current->thread.vscr)); current->thread.vrsave = 0; current->thread.used_vr = 0; #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE memset(current->thread.evr, 0, sizeof(current->thread.evr)); current->thread.acc = 0; current->thread.spefscr = 0; current->thread.used_spe = 0; #endif /* CONFIG_SPE */ } #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \