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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/powerpc/kernel/process.c | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'arch/powerpc/kernel/process.c')
-rw-r--r-- | arch/powerpc/kernel/process.c | 1339 |
1 files changed, 1339 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c new file mode 100644 index 00000000..4937c969 --- /dev/null +++ b/arch/powerpc/kernel/process.c @@ -0,0 +1,1339 @@ +/* + * 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/errno.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/smp.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/export.h> +#include <linux/kallsyms.h> +#include <linux/mqueue.h> +#include <linux/hardirq.h> +#include <linux/utsname.h> +#include <linux/ftrace.h> +#include <linux/kernel_stat.h> +#include <linux/personality.h> +#include <linux/random.h> +#include <linux/hw_breakpoint.h> + +#include <asm/pgtable.h> +#include <asm/uaccess.h> +#include <asm/io.h> +#include <asm/processor.h> +#include <asm/mmu.h> +#include <asm/prom.h> +#include <asm/machdep.h> +#include <asm/time.h> +#include <asm/runlatch.h> +#include <asm/syscalls.h> +#include <asm/switch_to.h> +#include <asm/debug.h> +#ifdef CONFIG_PPC64 +#include <asm/firmware.h> +#endif +#include <linux/kprobes.h> +#include <linux/kdebug.h> + +extern unsigned long _get_SP(void); + +#ifndef CONFIG_SMP +struct task_struct *last_task_used_math = NULL; +struct task_struct *last_task_used_altivec = NULL; +struct task_struct *last_task_used_vsx = NULL; +struct task_struct *last_task_used_spe = 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(tsk); + } + preempt_enable(); + } +} +EXPORT_SYMBOL_GPL(flush_fp_to_thread); + +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); + +#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 enable AltiVec for kernel - force */ +#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(tsk); + } + preempt_enable(); + } +} +EXPORT_SYMBOL_GPL(flush_altivec_to_thread); +#endif /* CONFIG_ALTIVEC */ + +#ifdef CONFIG_VSX +#if 0 +/* not currently used, but some crazy RAID module might want to later */ +void enable_kernel_vsx(void) +{ + WARN_ON(preemptible()); + +#ifdef CONFIG_SMP + if (current->thread.regs && (current->thread.regs->msr & MSR_VSX)) + giveup_vsx(current); + else + giveup_vsx(NULL); /* just enable vsx for kernel - force */ +#else + giveup_vsx(last_task_used_vsx); +#endif /* CONFIG_SMP */ +} +EXPORT_SYMBOL(enable_kernel_vsx); +#endif + +void giveup_vsx(struct task_struct *tsk) +{ + giveup_fpu(tsk); + giveup_altivec(tsk); + __giveup_vsx(tsk); +} + +void flush_vsx_to_thread(struct task_struct *tsk) +{ + if (tsk->thread.regs) { + preempt_disable(); + if (tsk->thread.regs->msr & MSR_VSX) { +#ifdef CONFIG_SMP + BUG_ON(tsk != current); +#endif + giveup_vsx(tsk); + } + preempt_enable(); + } +} +EXPORT_SYMBOL_GPL(flush_vsx_to_thread); +#endif /* CONFIG_VSX */ + +#ifdef CONFIG_SPE + +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); + +void flush_spe_to_thread(struct task_struct *tsk) +{ + if (tsk->thread.regs) { + preempt_disable(); + if (tsk->thread.regs->msr & MSR_SPE) { +#ifdef CONFIG_SMP + BUG_ON(tsk != current); +#endif + tsk->thread.spefscr = mfspr(SPRN_SPEFSCR); + giveup_spe(tsk); + } + preempt_enable(); + } +} +#endif /* CONFIG_SPE */ + +#ifndef CONFIG_SMP +/* + * If we are doing lazy switching of CPU state (FP, altivec or SPE), + * and the current task has some state, discard it. + */ +void discard_lazy_cpu_state(void) +{ + preempt_disable(); + 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 */ +#ifdef CONFIG_VSX + if (last_task_used_vsx == current) + last_task_used_vsx = NULL; +#endif /* CONFIG_VSX */ +#ifdef CONFIG_SPE + if (last_task_used_spe == current) + last_task_used_spe = NULL; +#endif + preempt_enable(); +} +#endif /* CONFIG_SMP */ + +#ifdef CONFIG_PPC_ADV_DEBUG_REGS +void do_send_trap(struct pt_regs *regs, unsigned long address, + unsigned long error_code, int signal_code, int breakpt) +{ + siginfo_t info; + + if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code, + 11, SIGSEGV) == NOTIFY_STOP) + return; + + /* Deliver the signal to userspace */ + info.si_signo = SIGTRAP; + info.si_errno = breakpt; /* breakpoint or watchpoint id */ + info.si_code = signal_code; + info.si_addr = (void __user *)address; + force_sig_info(SIGTRAP, &info, current); +} +#else /* !CONFIG_PPC_ADV_DEBUG_REGS */ +void do_dabr(struct pt_regs *regs, unsigned long address, + unsigned long error_code) +{ + siginfo_t info; + + if (notify_die(DIE_DABR_MATCH, "dabr_match", regs, error_code, + 11, SIGSEGV) == NOTIFY_STOP) + return; + + if (debugger_dabr_match(regs)) + return; + + /* Clear the DABR */ + set_dabr(0); + + /* Deliver the signal to userspace */ + info.si_signo = SIGTRAP; + info.si_errno = 0; + info.si_code = TRAP_HWBKPT; + info.si_addr = (void __user *)address; + force_sig_info(SIGTRAP, &info, current); +} +#endif /* CONFIG_PPC_ADV_DEBUG_REGS */ + +static DEFINE_PER_CPU(unsigned long, current_dabr); + +#ifdef CONFIG_PPC_ADV_DEBUG_REGS +/* + * Set the debug registers back to their default "safe" values. + */ +static void set_debug_reg_defaults(struct thread_struct *thread) +{ + thread->iac1 = thread->iac2 = 0; +#if CONFIG_PPC_ADV_DEBUG_IACS > 2 + thread->iac3 = thread->iac4 = 0; +#endif + thread->dac1 = thread->dac2 = 0; +#if CONFIG_PPC_ADV_DEBUG_DVCS > 0 + thread->dvc1 = thread->dvc2 = 0; +#endif + thread->dbcr0 = 0; +#ifdef CONFIG_BOOKE + /* + * Force User/Supervisor bits to b11 (user-only MSR[PR]=1) + */ + thread->dbcr1 = DBCR1_IAC1US | DBCR1_IAC2US | \ + DBCR1_IAC3US | DBCR1_IAC4US; + /* + * Force Data Address Compare User/Supervisor bits to be User-only + * (0b11 MSR[PR]=1) and set all other bits in DBCR2 register to be 0. + */ + thread->dbcr2 = DBCR2_DAC1US | DBCR2_DAC2US; +#else + thread->dbcr1 = 0; +#endif +} + +static void prime_debug_regs(struct thread_struct *thread) +{ + mtspr(SPRN_IAC1, thread->iac1); + mtspr(SPRN_IAC2, thread->iac2); +#if CONFIG_PPC_ADV_DEBUG_IACS > 2 + mtspr(SPRN_IAC3, thread->iac3); + mtspr(SPRN_IAC4, thread->iac4); +#endif + mtspr(SPRN_DAC1, thread->dac1); + mtspr(SPRN_DAC2, thread->dac2); +#if CONFIG_PPC_ADV_DEBUG_DVCS > 0 + mtspr(SPRN_DVC1, thread->dvc1); + mtspr(SPRN_DVC2, thread->dvc2); +#endif + mtspr(SPRN_DBCR0, thread->dbcr0); + mtspr(SPRN_DBCR1, thread->dbcr1); +#ifdef CONFIG_BOOKE + mtspr(SPRN_DBCR2, thread->dbcr2); +#endif +} +/* + * Unless neither the old or new thread are making use of the + * debug registers, set the debug registers from the values + * stored in the new thread. + */ +static void switch_booke_debug_regs(struct thread_struct *new_thread) +{ + if ((current->thread.dbcr0 & DBCR0_IDM) + || (new_thread->dbcr0 & DBCR0_IDM)) + prime_debug_regs(new_thread); +} +#else /* !CONFIG_PPC_ADV_DEBUG_REGS */ +#ifndef CONFIG_HAVE_HW_BREAKPOINT +static void set_debug_reg_defaults(struct thread_struct *thread) +{ + if (thread->dabr) { + thread->dabr = 0; + set_dabr(0); + } +} +#endif /* !CONFIG_HAVE_HW_BREAKPOINT */ +#endif /* CONFIG_PPC_ADV_DEBUG_REGS */ + +int set_dabr(unsigned long dabr) +{ + __get_cpu_var(current_dabr) = dabr; + + if (ppc_md.set_dabr) + return ppc_md.set_dabr(dabr); + + /* XXX should we have a CPU_FTR_HAS_DABR ? */ +#ifdef CONFIG_PPC_ADV_DEBUG_REGS + mtspr(SPRN_DAC1, dabr); +#ifdef CONFIG_PPC_47x + isync(); +#endif +#elif defined(CONFIG_PPC_BOOK3S) + mtspr(SPRN_DABR, dabr); +#endif + + + return 0; +} + +#ifdef CONFIG_PPC64 +DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array); +#endif + +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_PPC_BOOK3S_64 + struct ppc64_tlb_batch *batch; +#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_VSX + if (prev->thread.regs && (prev->thread.regs->msr & MSR_VSX)) + /* VMX and FPU registers are already save here */ + __giveup_vsx(prev); +#endif /* CONFIG_VSX */ +#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 */ + +#else /* CONFIG_SMP */ +#ifdef CONFIG_ALTIVEC + /* 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 */ +#ifdef CONFIG_VSX + if (new->thread.regs && last_task_used_vsx == new) + new->thread.regs->msr |= MSR_VSX; +#endif /* CONFIG_VSX */ +#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 */ + +#endif /* CONFIG_SMP */ + +#ifdef CONFIG_PPC_ADV_DEBUG_REGS + switch_booke_debug_regs(&new->thread); +#else +/* + * For PPC_BOOK3S_64, we use the hw-breakpoint interfaces that would + * schedule DABR + */ +#ifndef CONFIG_HAVE_HW_BREAKPOINT + if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) + set_dabr(new->thread.dabr); +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ +#endif + + + new_thread = &new->thread; + old_thread = ¤t->thread; + +#ifdef CONFIG_PPC64 + /* + * Collect processor utilization data per process + */ + 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; + } +#endif /* CONFIG_PPC64 */ + +#ifdef CONFIG_PPC_BOOK3S_64 + batch = &__get_cpu_var(ppc64_tlb_batch); + if (batch->active) { + current_thread_info()->local_flags |= _TLF_LAZY_MMU; + if (batch->index) + __flush_tlb_pending(batch); + batch->active = 0; + } +#endif /* CONFIG_PPC_BOOK3S_64 */ + + local_irq_save(flags); + + account_system_vtime(current); + account_process_vtime(current); + + /* + * We can't take a PMU exception inside _switch() since there is a + * window where the kernel stack SLB and the kernel stack are out + * of sync. Hard disable here. + */ + hard_irq_disable(); + last = _switch(old_thread, new_thread); + +#ifdef CONFIG_PPC_BOOK3S_64 + if (current_thread_info()->local_flags & _TLF_LAZY_MMU) { + current_thread_info()->local_flags &= ~_TLF_LAZY_MMU; + batch = &__get_cpu_var(ppc64_tlb_batch); + batch->active = 1; + } +#endif /* CONFIG_PPC_BOOK3S_64 */ + + 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 !defined(CONFIG_BOOKE) + /* If executing with the IMMU off, adjust pc rather + * than print XXXXXXXX. + */ + if (!(regs->msr & MSR_IR)) + pc = (unsigned long)phys_to_virt(pc); +#endif + + /* We use __get_user here *only* to avoid an OOPS on a + * bad address because the pc *should* only be a + * kernel address. + */ + if (!__kernel_text_address(pc) || + __get_user(instr, (unsigned int __user *)pc)) { + printk(KERN_CONT "XXXXXXXX "); + } else { + if (regs->nip == pc) + printk(KERN_CONT "<%08x> ", instr); + else + printk(KERN_CONT "%08x ", instr); + } + + pc += sizeof(int); + } + + printk("\n"); +} + +static struct regbit { + unsigned long bit; + const char *name; +} msr_bits[] = { +#if defined(CONFIG_PPC64) && !defined(CONFIG_BOOKE) + {MSR_SF, "SF"}, + {MSR_HV, "HV"}, +#endif + {MSR_VEC, "VEC"}, + {MSR_VSX, "VSX"}, +#ifdef CONFIG_BOOKE + {MSR_CE, "CE"}, +#endif + {MSR_EE, "EE"}, + {MSR_PR, "PR"}, + {MSR_FP, "FP"}, + {MSR_ME, "ME"}, +#ifdef CONFIG_BOOKE + {MSR_DE, "DE"}, +#else + {MSR_SE, "SE"}, + {MSR_BE, "BE"}, +#endif + {MSR_IR, "IR"}, + {MSR_DR, "DR"}, + {MSR_PMM, "PMM"}, +#ifndef CONFIG_BOOKE + {MSR_RI, "RI"}, + {MSR_LE, "LE"}, +#endif + {0, NULL} +}; + +static void printbits(unsigned long val, struct regbit *bits) +{ + const char *sep = ""; + + printk("<"); + for (; bits->bit; ++bits) + if (val & bits->bit) { + printk("%s%s", sep, bits->name); + sep = ","; + } + printk(">"); +} + +#ifdef CONFIG_PPC64 +#define REG "%016lx" +#define REGS_PER_LINE 4 +#define LAST_VOLATILE 13 +#else +#define REG "%08lx" +#define REGS_PER_LINE 8 +#define LAST_VOLATILE 12 +#endif + +void show_regs(struct pt_regs * regs) +{ + int i, trap; + + printk("NIP: "REG" LR: "REG" CTR: "REG"\n", + regs->nip, regs->link, regs->ctr); + printk("REGS: %p TRAP: %04lx %s (%s)\n", + regs, regs->trap, print_tainted(), init_utsname()->release); + printk("MSR: "REG" ", regs->msr); + printbits(regs->msr, msr_bits); + printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer); +#ifdef CONFIG_PPC64 + printk("SOFTE: %ld\n", regs->softe); +#endif + trap = TRAP(regs); + if ((regs->trap != 0xc00) && cpu_has_feature(CPU_FTR_CFAR)) + printk("CFAR: "REG"\n", regs->orig_gpr3); + if (trap == 0x300 || trap == 0x600) +#if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) + printk("DEAR: "REG", ESR: "REG"\n", regs->dar, regs->dsisr); +#else + printk("DAR: "REG", DSISR: %08lx\n", regs->dar, regs->dsisr); +#endif + printk("TASK = %p[%d] '%s' THREAD: %p", + current, task_pid_nr(current), current->comm, task_thread_info(current)); + +#ifdef CONFIG_SMP + printk(" CPU: %d", raw_smp_processor_id()); +#endif /* CONFIG_SMP */ + + for (i = 0; i < 32; i++) { + if ((i % REGS_PER_LINE) == 0) + printk("\nGPR%02d: ", i); + printk(REG " ", regs->gpr[i]); + if (i == LAST_VOLATILE && !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 ["REG"] %pS\n", regs->nip, (void *)regs->nip); + printk("LR ["REG"] %pS\n", regs->link, (void *)regs->link); +#endif + show_stack(current, (unsigned long *) regs->gpr[1]); + if (!user_mode(regs)) + show_instructions(regs); +} + +void exit_thread(void) +{ + discard_lazy_cpu_state(); +} + +void flush_thread(void) +{ + discard_lazy_cpu_state(); + +#ifdef CONFIG_HAVE_HW_BREAKPOINT + flush_ptrace_hw_breakpoint(current); +#else /* CONFIG_HAVE_HW_BREAKPOINT */ + set_debug_reg_defaults(¤t->thread); +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ +} + +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); + flush_vsx_to_thread(current); + flush_spe_to_thread(current); +#ifdef CONFIG_HAVE_HW_BREAKPOINT + flush_ptrace_hw_breakpoint(tsk); +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ +} + +/* + * Copy a thread.. + */ +extern unsigned long dscr_default; /* defined in arch/powerpc/kernel/sysfs.c */ + +int copy_thread(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)task_stack_page(p) + THREAD_SIZE; + + 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); +#ifdef CONFIG_PPC32 + childregs->gpr[2] = (unsigned long) p; +#else + clear_tsk_thread_flag(p, TIF_32BIT); +#endif + p->thread.regs = NULL; /* no user register state */ + } else { + childregs->gpr[1] = usp; + p->thread.regs = childregs; + if (clone_flags & CLONE_SETTLS) { +#ifdef CONFIG_PPC64 + if (!is_32bit_task()) + childregs->gpr[13] = childregs->gpr[6]; + else +#endif + childregs->gpr[2] = 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; + p->thread.ksp_limit = (unsigned long)task_stack_page(p) + + _ALIGN_UP(sizeof(struct thread_info), 16); + +#ifdef CONFIG_PPC_STD_MMU_64 + if (mmu_has_feature(MMU_FTR_SLB)) { + unsigned long sp_vsid; + unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp; + + if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) + sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T) + << SLB_VSID_SHIFT_1T; + else + sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M) + << SLB_VSID_SHIFT; + sp_vsid |= SLB_VSID_KERNEL | llp; + p->thread.ksp_vsid = sp_vsid; + } +#endif /* CONFIG_PPC_STD_MMU_64 */ +#ifdef CONFIG_PPC64 + if (cpu_has_feature(CPU_FTR_DSCR)) { + if (current->thread.dscr_inherit) { + p->thread.dscr_inherit = 1; + p->thread.dscr = current->thread.dscr; + } else if (0 != dscr_default) { + p->thread.dscr_inherit = 1; + p->thread.dscr = dscr_default; + } else { + p->thread.dscr_inherit = 0; + p->thread.dscr = 0; + } + } +#endif + + /* + * 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. + */ +#ifdef CONFIG_PPC64 + kregs->nip = *((unsigned long *)ret_from_fork); +#else + kregs->nip = (unsigned long)ret_from_fork; +#endif + + return 0; +} + +/* + * Set up a thread for executing a new program + */ +void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp) +{ +#ifdef CONFIG_PPC64 + unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */ +#endif + + /* + * If we exec out of a kernel thread then thread.regs will not be + * set. Do it now. + */ + if (!current->thread.regs) { + struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE; + current->thread.regs = regs - 1; + } + + memset(regs->gpr, 0, sizeof(regs->gpr)); + regs->ctr = 0; + regs->link = 0; + regs->xer = 0; + regs->ccr = 0; + regs->gpr[1] = sp; + + /* + * We have just cleared all the nonvolatile GPRs, so make + * FULL_REGS(regs) return true. This is necessary to allow + * ptrace to examine the thread immediately after exec. + */ + regs->trap &= ~1UL; + +#ifdef CONFIG_PPC32 + regs->mq = 0; + regs->nip = start; + regs->msr = MSR_USER; +#else + if (!is_32bit_task()) { + unsigned long entry, toc; + + /* start 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. + */ + __get_user(entry, (unsigned long __user *)start); + __get_user(toc, (unsigned long __user *)start+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; + } + regs->nip = entry; + regs->gpr[2] = toc; + regs->msr = MSR_USER64; + } else { + regs->nip = start; + regs->gpr[2] = 0; + regs->msr = MSR_USER32; + } +#endif + + discard_lazy_cpu_state(); +#ifdef CONFIG_VSX + current->thread.used_vsr = 0; +#endif + memset(current->thread.fpr, 0, sizeof(current->thread.fpr)); + current->thread.fpscr.val = 0; +#ifdef CONFIG_ALTIVEC + memset(current->thread.vr, 0, sizeof(current->thread.vr)); + memset(¤t->thread.vscr, 0, sizeof(current->thread.vscr)); + current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */ + 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 \ + | PR_FP_EXC_RES | PR_FP_EXC_INV) + +int set_fpexc_mode(struct task_struct *tsk, unsigned int val) +{ + struct pt_regs *regs = tsk->thread.regs; + + /* This is a bit hairy. If we are an SPE enabled processor + * (have embedded fp) we store the IEEE exception enable flags in + * fpexc_mode. fpexc_mode is also used for setting FP exception + * mode (asyn, precise, disabled) for 'Classic' FP. */ + if (val & PR_FP_EXC_SW_ENABLE) { +#ifdef CONFIG_SPE + if (cpu_has_feature(CPU_FTR_SPE)) { + tsk->thread.fpexc_mode = val & + (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT); + return 0; + } else { + return -EINVAL; + } +#else + return -EINVAL; +#endif + } + + /* on a CONFIG_SPE this does not hurt us. The bits that + * __pack_fe01 use do not overlap with bits used for + * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits + * on CONFIG_SPE implementations are reserved so writing to + * them does not change anything */ + 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; + + if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE) +#ifdef CONFIG_SPE + if (cpu_has_feature(CPU_FTR_SPE)) + val = tsk->thread.fpexc_mode; + else + return -EINVAL; +#else + return -EINVAL; +#endif + else + val = __unpack_fe01(tsk->thread.fpexc_mode); + return put_user(val, (unsigned int __user *) adr); +} + +int set_endian(struct task_struct *tsk, unsigned int val) +{ + struct pt_regs *regs = tsk->thread.regs; + + if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) || + (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE))) + return -EINVAL; + + if (regs == NULL) + return -EINVAL; + + if (val == PR_ENDIAN_BIG) + regs->msr &= ~MSR_LE; + else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE) + regs->msr |= MSR_LE; + else + return -EINVAL; + + return 0; +} + +int get_endian(struct task_struct *tsk, unsigned long adr) +{ + struct pt_regs *regs = tsk->thread.regs; + unsigned int val; + + if (!cpu_has_feature(CPU_FTR_PPC_LE) && + !cpu_has_feature(CPU_FTR_REAL_LE)) + return -EINVAL; + + if (regs == NULL) + return -EINVAL; + + if (regs->msr & MSR_LE) { + if (cpu_has_feature(CPU_FTR_REAL_LE)) + val = PR_ENDIAN_LITTLE; + else + val = PR_ENDIAN_PPC_LITTLE; + } else + val = PR_ENDIAN_BIG; + + return put_user(val, (unsigned int __user *)adr); +} + +int set_unalign_ctl(struct task_struct *tsk, unsigned int val) +{ + tsk->thread.align_ctl = val; + return 0; +} + +int get_unalign_ctl(struct task_struct *tsk, unsigned long adr) +{ + return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr); +} + +#define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff)) + +int sys_clone(unsigned long clone_flags, unsigned long usp, + int __user *parent_tidp, void __user *child_threadptr, + int __user *child_tidp, int p6, + struct pt_regs *regs) +{ + CHECK_FULL_REGS(regs); + if (usp == 0) + usp = regs->gpr[1]; /* stack pointer for child */ +#ifdef CONFIG_PPC64 + if (is_32bit_task()) { + parent_tidp = TRUNC_PTR(parent_tidp); + child_tidp = TRUNC_PTR(child_tidp); + } +#endif + return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp); +} + +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) +{ + CHECK_FULL_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) +{ + CHECK_FULL_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((const char __user *) a0); + error = PTR_ERR(filename); + if (IS_ERR(filename)) + goto out; + flush_fp_to_thread(current); + flush_altivec_to_thread(current); + flush_spe_to_thread(current); + error = do_execve(filename, + (const char __user *const __user *) a1, + (const char __user *const __user *) a2, regs); + putname(filename); +out: + return error; +} + +static inline int valid_irq_stack(unsigned long sp, struct task_struct *p, + unsigned long nbytes) +{ + unsigned long stack_page; + unsigned long cpu = task_cpu(p); + + /* + * Avoid crashing if the stack has overflowed and corrupted + * task_cpu(p), which is in the thread_info struct. + */ + if (cpu < NR_CPUS && cpu_possible(cpu)) { + stack_page = (unsigned long) hardirq_ctx[cpu]; + if (sp >= stack_page + sizeof(struct thread_struct) + && sp <= stack_page + THREAD_SIZE - nbytes) + return 1; + + stack_page = (unsigned long) softirq_ctx[cpu]; + if (sp >= stack_page + sizeof(struct thread_struct) + && sp <= stack_page + THREAD_SIZE - nbytes) + return 1; + } + return 0; +} + +int validate_sp(unsigned long sp, struct task_struct *p, + unsigned long nbytes) +{ + unsigned long stack_page = (unsigned long)task_stack_page(p); + + if (sp >= stack_page + sizeof(struct thread_struct) + && sp <= stack_page + THREAD_SIZE - nbytes) + return 1; + + return valid_irq_stack(sp, p, nbytes); +} + +EXPORT_SYMBOL(validate_sp); + +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, STACK_FRAME_OVERHEAD)) + return 0; + + do { + sp = *(unsigned long *)sp; + if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD)) + return 0; + if (count > 0) { + ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE]; + if (!in_sched_functions(ip)) + return ip; + } + } while (count++ < 16); + return 0; +} + +static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH; + +void show_stack(struct task_struct *tsk, unsigned long *stack) +{ + unsigned long sp, ip, lr, newsp; + int count = 0; + int firstframe = 1; +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + int curr_frame = current->curr_ret_stack; + extern void return_to_handler(void); + unsigned long rth = (unsigned long)return_to_handler; + unsigned long mrth = -1; +#ifdef CONFIG_PPC64 + extern void mod_return_to_handler(void); + rth = *(unsigned long *)rth; + mrth = (unsigned long)mod_return_to_handler; + mrth = *(unsigned long *)mrth; +#endif +#endif + + sp = (unsigned long) stack; + if (tsk == NULL) + tsk = current; + if (sp == 0) { + if (tsk == current) + asm("mr %0,1" : "=r" (sp)); + else + sp = tsk->thread.ksp; + } + + lr = 0; + printk("Call Trace:\n"); + do { + if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD)) + return; + + stack = (unsigned long *) sp; + newsp = stack[0]; + ip = stack[STACK_FRAME_LR_SAVE]; + if (!firstframe || ip != lr) { + printk("["REG"] ["REG"] %pS", sp, ip, (void *)ip); +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + if ((ip == rth || ip == mrth) && curr_frame >= 0) { + printk(" (%pS)", + (void *)current->ret_stack[curr_frame].ret); + curr_frame--; + } +#endif + 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, tsk, STACK_INT_FRAME_SIZE) + && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) { + struct pt_regs *regs = (struct pt_regs *) + (sp + STACK_FRAME_OVERHEAD); + lr = regs->link; + printk("--- Exception: %lx at %pS\n LR = %pS\n", + regs->trap, (void *)regs->nip, (void *)lr); + firstframe = 1; + } + + sp = newsp; + } while (count++ < kstack_depth_to_print); +} + +void dump_stack(void) +{ + show_stack(current, NULL); +} +EXPORT_SYMBOL(dump_stack); + +#ifdef CONFIG_PPC64 +/* Called with hard IRQs off */ +void __ppc64_runlatch_on(void) +{ + struct thread_info *ti = current_thread_info(); + unsigned long ctrl; + + ctrl = mfspr(SPRN_CTRLF); + ctrl |= CTRL_RUNLATCH; + mtspr(SPRN_CTRLT, ctrl); + + ti->local_flags |= _TLF_RUNLATCH; +} + +/* Called with hard IRQs off */ +void __ppc64_runlatch_off(void) +{ + struct thread_info *ti = current_thread_info(); + unsigned long ctrl; + + ti->local_flags &= ~_TLF_RUNLATCH; + + ctrl = mfspr(SPRN_CTRLF); + ctrl &= ~CTRL_RUNLATCH; + mtspr(SPRN_CTRLT, ctrl); +} +#endif /* CONFIG_PPC64 */ + +#if THREAD_SHIFT < PAGE_SHIFT + +static struct kmem_cache *thread_info_cache; + +struct thread_info *alloc_thread_info_node(struct task_struct *tsk, int node) +{ + struct thread_info *ti; + + ti = kmem_cache_alloc_node(thread_info_cache, GFP_KERNEL, node); + if (unlikely(ti == NULL)) + return NULL; +#ifdef CONFIG_DEBUG_STACK_USAGE + memset(ti, 0, THREAD_SIZE); +#endif + return ti; +} + +void free_thread_info(struct thread_info *ti) +{ + kmem_cache_free(thread_info_cache, ti); +} + +void thread_info_cache_init(void) +{ + thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE, + THREAD_SIZE, 0, NULL); + BUG_ON(thread_info_cache == NULL); +} + +#endif /* THREAD_SHIFT < PAGE_SHIFT */ + +unsigned long arch_align_stack(unsigned long sp) +{ + if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) + sp -= get_random_int() & ~PAGE_MASK; + return sp & ~0xf; +} + +static inline unsigned long brk_rnd(void) +{ + unsigned long rnd = 0; + + /* 8MB for 32bit, 1GB for 64bit */ + if (is_32bit_task()) + rnd = (long)(get_random_int() % (1<<(23-PAGE_SHIFT))); + else + rnd = (long)(get_random_int() % (1<<(30-PAGE_SHIFT))); + + return rnd << PAGE_SHIFT; +} + +unsigned long arch_randomize_brk(struct mm_struct *mm) +{ + unsigned long base = mm->brk; + unsigned long ret; + +#ifdef CONFIG_PPC_STD_MMU_64 + /* + * If we are using 1TB segments and we are allowed to randomise + * the heap, we can put it above 1TB so it is backed by a 1TB + * segment. Otherwise the heap will be in the bottom 1TB + * which always uses 256MB segments and this may result in a + * performance penalty. + */ + if (!is_32bit_task() && (mmu_highuser_ssize == MMU_SEGSIZE_1T)) + base = max_t(unsigned long, mm->brk, 1UL << SID_SHIFT_1T); +#endif + + ret = PAGE_ALIGN(base + brk_rnd()); + + if (ret < mm->brk) + return mm->brk; + + return ret; +} + +unsigned long randomize_et_dyn(unsigned long base) +{ + unsigned long ret = PAGE_ALIGN(base + brk_rnd()); + + if (ret < base) + return base; + + return ret; +} |