/* * linux/arch/arm/kernel/process.c * * Copyright (C) 1996-2000 Russell King - Converted to ARM. * Original Copyright (C) 1995 Linus Torvalds * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #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 #ifdef CONFIG_CC_STACKPROTECTOR #include unsigned long __stack_chk_guard __read_mostly; EXPORT_SYMBOL(__stack_chk_guard); #endif static const char *processor_modes[] __maybe_unused = { "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" , "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26", "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "MON_32" , "ABT_32" , "UK8_32" , "UK9_32" , "HYP_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32" }; static const char *isa_modes[] __maybe_unused = { "ARM" , "Thumb" , "Jazelle", "ThumbEE" }; /* * This is our default idle handler. */ void (*arm_pm_idle)(void); /* * Called from the core idle loop. */ void arch_cpu_idle(void) { if (arm_pm_idle) arm_pm_idle(); else cpu_do_idle(); local_irq_enable(); } void arch_cpu_idle_prepare(void) { local_fiq_enable(); } void arch_cpu_idle_enter(void) { ledtrig_cpu(CPU_LED_IDLE_START); #ifdef CONFIG_PL310_ERRATA_769419 wmb(); #endif } void arch_cpu_idle_exit(void) { ledtrig_cpu(CPU_LED_IDLE_END); } void __show_regs(struct pt_regs *regs) { unsigned long flags; char buf[64]; show_regs_print_info(KERN_DEFAULT); print_symbol("PC is at %s\n", instruction_pointer(regs)); print_symbol("LR is at %s\n", regs->ARM_lr); printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n" "sp : %08lx ip : %08lx fp : %08lx\n", regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr, regs->ARM_sp, regs->ARM_ip, regs->ARM_fp); printk("r10: %08lx r9 : %08lx r8 : %08lx\n", regs->ARM_r10, regs->ARM_r9, regs->ARM_r8); printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", regs->ARM_r7, regs->ARM_r6, regs->ARM_r5, regs->ARM_r4); printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", regs->ARM_r3, regs->ARM_r2, regs->ARM_r1, regs->ARM_r0); flags = regs->ARM_cpsr; buf[0] = flags & PSR_N_BIT ? 'N' : 'n'; buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z'; buf[2] = flags & PSR_C_BIT ? 'C' : 'c'; buf[3] = flags & PSR_V_BIT ? 'V' : 'v'; buf[4] = '\0'; #ifndef CONFIG_CPU_V7M { unsigned int domain = get_domain(); const char *segment; #ifdef CONFIG_CPU_SW_DOMAIN_PAN /* * Get the domain register for the parent context. In user * mode, we don't save the DACR, so lets use what it should * be. For other modes, we place it after the pt_regs struct. */ if (user_mode(regs)) domain = DACR_UACCESS_ENABLE; else domain = *(unsigned int *)(regs + 1); #endif if ((domain & domain_mask(DOMAIN_USER)) == domain_val(DOMAIN_USER, DOMAIN_NOACCESS)) segment = "none"; else if (get_fs() == get_ds()) segment = "kernel"; else segment = "user"; printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n", buf, interrupts_enabled(regs) ? "n" : "ff", fast_interrupts_enabled(regs) ? "n" : "ff", processor_modes[processor_mode(regs)], isa_modes[isa_mode(regs)], segment); } #else printk("xPSR: %08lx\n", regs->ARM_cpsr); #endif #ifdef CONFIG_CPU_CP15 { unsigned int ctrl; buf[0] = '\0'; #ifdef CONFIG_CPU_CP15_MMU { unsigned int transbase, dac = get_domain(); asm("mrc p15, 0, %0, c2, c0\n\t" : "=r" (transbase)); snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x", transbase, dac); } #endif asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl)); printk("Control: %08x%s\n", ctrl, buf); } #endif } void show_regs(struct pt_regs * regs) { __show_regs(regs); dump_stack(); } ATOMIC_NOTIFIER_HEAD(thread_notify_head); EXPORT_SYMBOL_GPL(thread_notify_head); /* * Free current thread data structures etc.. */ void exit_thread(void) { thread_notify(THREAD_NOTIFY_EXIT, current_thread_info()); } void flush_thread(void) { struct thread_info *thread = current_thread_info(); struct task_struct *tsk = current; flush_ptrace_hw_breakpoint(tsk); memset(thread->used_cp, 0, sizeof(thread->used_cp)); memset(&tsk->thread.debug, 0, sizeof(struct debug_info)); memset(&thread->fpstate, 0, sizeof(union fp_state)); flush_tls(); thread_notify(THREAD_NOTIFY_FLUSH, thread); } void release_thread(struct task_struct *dead_task) { } asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); int copy_thread(unsigned long clone_flags, unsigned long stack_start, unsigned long stk_sz, struct task_struct *p) { struct thread_info *thread = task_thread_info(p); struct pt_regs *childregs = task_pt_regs(p); memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); /* * Copy the initial value of the domain access control register * from the current thread: thread->addr_limit will have been * copied from the current thread via setup_thread_stack() in * kernel/fork.c */ thread->cpu_domain = get_domain(); if (likely(!(p->flags & PF_KTHREAD))) { *childregs = *current_pt_regs(); childregs->ARM_r0 = 0; if (stack_start) childregs->ARM_sp = stack_start; } else { memset(childregs, 0, sizeof(struct pt_regs)); thread->cpu_context.r4 = stk_sz; thread->cpu_context.r5 = stack_start; childregs->ARM_cpsr = SVC_MODE; } thread->cpu_context.pc = (unsigned long)ret_from_fork; thread->cpu_context.sp = (unsigned long)childregs; clear_ptrace_hw_breakpoint(p); if (clone_flags & CLONE_SETTLS) thread->tp_value[0] = childregs->ARM_r3; thread->tp_value[1] = get_tpuser(); thread_notify(THREAD_NOTIFY_COPY, thread); return 0; } /* * Fill in the task's elfregs structure for a core dump. */ int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs) { elf_core_copy_regs(elfregs, task_pt_regs(t)); return 1; } /* * fill in the fpe structure for a core dump... */ int dump_fpu (struct pt_regs *regs, struct user_fp *fp) { struct thread_info *thread = current_thread_info(); int used_math = thread->used_cp[1] | thread->used_cp[2]; if (used_math) memcpy(fp, &thread->fpstate.soft, sizeof (*fp)); return used_math != 0; } EXPORT_SYMBOL(dump_fpu); unsigned long get_wchan(struct task_struct *p) { struct stackframe frame; unsigned long stack_page; int count = 0; if (!p || p == current || p->state == TASK_RUNNING) return 0; frame.fp = thread_saved_fp(p); frame.sp = thread_saved_sp(p); frame.lr = 0; /* recovered from the stack */ frame.pc = thread_saved_pc(p); stack_page = (unsigned long)task_stack_page(p); do { if (frame.sp < stack_page || frame.sp >= stack_page + THREAD_SIZE || unwind_frame(&frame) < 0) return 0; if (!in_sched_functions(frame.pc)) return frame.pc; } while (count ++ < 16); return 0; } unsigned long arch_randomize_brk(struct mm_struct *mm) { unsigned long range_end = mm->brk + 0x02000000; return randomize_range(mm->brk, range_end, 0) ? : mm->brk; } #ifdef CONFIG_MMU #ifdef CONFIG_KUSER_HELPERS /* * The vectors page is always readable from user space for the * atomic helpers. Insert it into the gate_vma so that it is visible * through ptrace and /proc//mem. */ static struct vm_area_struct gate_vma = { .vm_start = 0xffff0000, .vm_end = 0xffff0000 + PAGE_SIZE, .vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC, }; static int __init gate_vma_init(void) { gate_vma.vm_page_prot = PAGE_READONLY_EXEC; return 0; } arch_initcall(gate_vma_init); struct vm_area_struct *get_gate_vma(struct mm_struct *mm) { return &gate_vma; } int in_gate_area(struct mm_struct *mm, unsigned long addr) { return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end); } int in_gate_area_no_mm(unsigned long addr) { return in_gate_area(NULL, addr); } #define is_gate_vma(vma) ((vma) == &gate_vma) #else #define is_gate_vma(vma) 0 #endif const char *arch_vma_name(struct vm_area_struct *vma) { return is_gate_vma(vma) ? "[vectors]" : NULL; } /* If possible, provide a placement hint at a random offset from the * stack for the sigpage and vdso pages. */ static unsigned long sigpage_addr(const struct mm_struct *mm, unsigned int npages) { unsigned long offset; unsigned long first; unsigned long last; unsigned long addr; unsigned int slots; first = PAGE_ALIGN(mm->start_stack); last = TASK_SIZE - (npages << PAGE_SHIFT); /* No room after stack? */ if (first > last) return 0; /* Just enough room? */ if (first == last) return first; slots = ((last - first) >> PAGE_SHIFT) + 1; offset = get_random_int() % slots; addr = first + (offset << PAGE_SHIFT); return addr; } static struct page *signal_page; extern struct page *get_signal_page(void); static const struct vm_special_mapping sigpage_mapping = { .name = "[sigpage]", .pages = &signal_page, }; int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; unsigned long npages; unsigned long addr; unsigned long hint; int ret = 0; if (!signal_page) signal_page = get_signal_page(); if (!signal_page) return -ENOMEM; npages = 1; /* for sigpage */ npages += vdso_total_pages; down_write(&mm->mmap_sem); hint = sigpage_addr(mm, npages); addr = get_unmapped_area(NULL, hint, npages << PAGE_SHIFT, 0, 0); if (IS_ERR_VALUE(addr)) { ret = addr; goto up_fail; } vma = _install_special_mapping(mm, addr, PAGE_SIZE, VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, &sigpage_mapping); if (IS_ERR(vma)) { ret = PTR_ERR(vma); goto up_fail; } mm->context.sigpage = addr; /* Unlike the sigpage, failure to install the vdso is unlikely * to be fatal to the process, so no error check needed * here. */ arm_install_vdso(mm, addr + PAGE_SIZE); up_fail: up_write(&mm->mmap_sem); return ret; } #endif