diff options
Diffstat (limited to 'arch/avr32/kernel/ptrace.c')
| -rw-r--r-- | arch/avr32/kernel/ptrace.c | 357 |
1 files changed, 0 insertions, 357 deletions
diff --git a/arch/avr32/kernel/ptrace.c b/arch/avr32/kernel/ptrace.c deleted file mode 100644 index 41a14e96a1db..000000000000 --- a/arch/avr32/kernel/ptrace.c +++ /dev/null @@ -1,357 +0,0 @@ -/* - * Copyright (C) 2004-2006 Atmel Corporation - * - * 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. - */ -#undef DEBUG -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/sched/task_stack.h> -#include <linux/mm.h> -#include <linux/ptrace.h> -#include <linux/errno.h> -#include <linux/user.h> -#include <linux/security.h> -#include <linux/unistd.h> -#include <linux/notifier.h> - -#include <asm/traps.h> -#include <linux/uaccess.h> -#include <asm/ocd.h> -#include <asm/mmu_context.h> -#include <linux/kdebug.h> - -static struct pt_regs *get_user_regs(struct task_struct *tsk) -{ - return (struct pt_regs *)((unsigned long)task_stack_page(tsk) + - THREAD_SIZE - sizeof(struct pt_regs)); -} - -void user_enable_single_step(struct task_struct *tsk) -{ - pr_debug("user_enable_single_step: pid=%u, PC=0x%08lx, SR=0x%08lx\n", - tsk->pid, task_pt_regs(tsk)->pc, task_pt_regs(tsk)->sr); - - /* - * We can't schedule in Debug mode, so when TIF_BREAKPOINT is - * set, the system call or exception handler will do a - * breakpoint to enter monitor mode before returning to - * userspace. - * - * The monitor code will then notice that TIF_SINGLE_STEP is - * set and return to userspace with single stepping enabled. - * The CPU will then enter monitor mode again after exactly - * one instruction has been executed, and the monitor code - * will then send a SIGTRAP to the process. - */ - set_tsk_thread_flag(tsk, TIF_BREAKPOINT); - set_tsk_thread_flag(tsk, TIF_SINGLE_STEP); -} - -void user_disable_single_step(struct task_struct *child) -{ - /* XXX(hch): a no-op here seems wrong.. */ -} - -/* - * Called by kernel/ptrace.c when detaching - * - * Make sure any single step bits, etc. are not set - */ -void ptrace_disable(struct task_struct *child) -{ - clear_tsk_thread_flag(child, TIF_SINGLE_STEP); - clear_tsk_thread_flag(child, TIF_BREAKPOINT); - ocd_disable(child); -} - -/* - * Read the word at offset "offset" into the task's "struct user". We - * actually access the pt_regs struct stored on the kernel stack. - */ -static int ptrace_read_user(struct task_struct *tsk, unsigned long offset, - unsigned long __user *data) -{ - unsigned long *regs; - unsigned long value; - - if (offset & 3 || offset >= sizeof(struct user)) { - printk("ptrace_read_user: invalid offset 0x%08lx\n", offset); - return -EIO; - } - - regs = (unsigned long *)get_user_regs(tsk); - - value = 0; - if (offset < sizeof(struct pt_regs)) - value = regs[offset / sizeof(regs[0])]; - - pr_debug("ptrace_read_user(%s[%u], %#lx, %p) -> %#lx\n", - tsk->comm, tsk->pid, offset, data, value); - - return put_user(value, data); -} - -/* - * Write the word "value" to offset "offset" into the task's "struct - * user". We actually access the pt_regs struct stored on the kernel - * stack. - */ -static int ptrace_write_user(struct task_struct *tsk, unsigned long offset, - unsigned long value) -{ - unsigned long *regs; - - pr_debug("ptrace_write_user(%s[%u], %#lx, %#lx)\n", - tsk->comm, tsk->pid, offset, value); - - if (offset & 3 || offset >= sizeof(struct user)) { - pr_debug(" invalid offset 0x%08lx\n", offset); - return -EIO; - } - - if (offset >= sizeof(struct pt_regs)) - return 0; - - regs = (unsigned long *)get_user_regs(tsk); - regs[offset / sizeof(regs[0])] = value; - - return 0; -} - -static int ptrace_getregs(struct task_struct *tsk, void __user *uregs) -{ - struct pt_regs *regs = get_user_regs(tsk); - - return copy_to_user(uregs, regs, sizeof(*regs)) ? -EFAULT : 0; -} - -static int ptrace_setregs(struct task_struct *tsk, const void __user *uregs) -{ - struct pt_regs newregs; - int ret; - - ret = -EFAULT; - if (copy_from_user(&newregs, uregs, sizeof(newregs)) == 0) { - struct pt_regs *regs = get_user_regs(tsk); - - ret = -EINVAL; - if (valid_user_regs(&newregs)) { - *regs = newregs; - ret = 0; - } - } - - return ret; -} - -long arch_ptrace(struct task_struct *child, long request, - unsigned long addr, unsigned long data) -{ - int ret; - void __user *datap = (void __user *) data; - - switch (request) { - /* Read the word at location addr in the child process */ - case PTRACE_PEEKTEXT: - case PTRACE_PEEKDATA: - ret = generic_ptrace_peekdata(child, addr, data); - break; - - case PTRACE_PEEKUSR: - ret = ptrace_read_user(child, addr, datap); - break; - - /* Write the word in data at location addr */ - case PTRACE_POKETEXT: - case PTRACE_POKEDATA: - ret = generic_ptrace_pokedata(child, addr, data); - break; - - case PTRACE_POKEUSR: - ret = ptrace_write_user(child, addr, data); - break; - - case PTRACE_GETREGS: - ret = ptrace_getregs(child, datap); - break; - - case PTRACE_SETREGS: - ret = ptrace_setregs(child, datap); - break; - - default: - ret = ptrace_request(child, request, addr, data); - break; - } - - return ret; -} - -asmlinkage void syscall_trace(void) -{ - if (!test_thread_flag(TIF_SYSCALL_TRACE)) - return; - if (!(current->ptrace & PT_PTRACED)) - return; - - /* The 0x80 provides a way for the tracing parent to - * distinguish between a syscall stop and SIGTRAP delivery */ - ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) - ? 0x80 : 0)); - - /* - * this isn't the same as continuing with a signal, but it - * will do for normal use. strace only continues with a - * signal if the stopping signal is not SIGTRAP. -brl - */ - if (current->exit_code) { - pr_debug("syscall_trace: sending signal %d to PID %u\n", - current->exit_code, current->pid); - send_sig(current->exit_code, current, 1); - current->exit_code = 0; - } -} - -/* - * debug_trampoline() is an assembly stub which will store all user - * registers on the stack and execute a breakpoint instruction. - * - * If we single-step into an exception handler which runs with - * interrupts disabled the whole time so it doesn't have to check for - * pending work, its return address will be modified so that it ends - * up returning to debug_trampoline. - * - * If the exception handler decides to store the user context and - * enable interrupts after all, it will restore the original return - * address and status register value. Before it returns, it will - * notice that TIF_BREAKPOINT is set and execute a breakpoint - * instruction. - */ -extern void debug_trampoline(void); - -asmlinkage struct pt_regs *do_debug(struct pt_regs *regs) -{ - struct thread_info *ti; - unsigned long trampoline_addr; - u32 status; - u32 ctrl; - int code; - - status = ocd_read(DS); - ti = current_thread_info(); - code = TRAP_BRKPT; - - pr_debug("do_debug: status=0x%08x PC=0x%08lx SR=0x%08lx tif=0x%08lx\n", - status, regs->pc, regs->sr, ti->flags); - - if (!user_mode(regs)) { - unsigned long die_val = DIE_BREAKPOINT; - - if (status & (1 << OCD_DS_SSS_BIT)) - die_val = DIE_SSTEP; - - if (notify_die(die_val, "ptrace", regs, 0, 0, SIGTRAP) - == NOTIFY_STOP) - return regs; - - if ((status & (1 << OCD_DS_SWB_BIT)) - && test_and_clear_ti_thread_flag( - ti, TIF_BREAKPOINT)) { - /* - * Explicit breakpoint from trampoline or - * exception/syscall/interrupt handler. - * - * The real saved regs are on the stack right - * after the ones we saved on entry. - */ - regs++; - pr_debug(" -> TIF_BREAKPOINT done, adjusted regs:" - "PC=0x%08lx SR=0x%08lx\n", - regs->pc, regs->sr); - BUG_ON(!user_mode(regs)); - - if (test_thread_flag(TIF_SINGLE_STEP)) { - pr_debug("Going to do single step...\n"); - return regs; - } - - /* - * No TIF_SINGLE_STEP means we're done - * stepping over a syscall. Do the trap now. - */ - code = TRAP_TRACE; - } else if ((status & (1 << OCD_DS_SSS_BIT)) - && test_ti_thread_flag(ti, TIF_SINGLE_STEP)) { - - pr_debug("Stepped into something, " - "setting TIF_BREAKPOINT...\n"); - set_ti_thread_flag(ti, TIF_BREAKPOINT); - - /* - * We stepped into an exception, interrupt or - * syscall handler. Some exception handlers - * don't check for pending work, so we need to - * set up a trampoline just in case. - * - * The exception entry code will undo the - * trampoline stuff if it does a full context - * save (which also means that it'll check for - * pending work later.) - */ - if ((regs->sr & MODE_MASK) == MODE_EXCEPTION) { - trampoline_addr - = (unsigned long)&debug_trampoline; - - pr_debug("Setting up trampoline...\n"); - ti->rar_saved = sysreg_read(RAR_EX); - ti->rsr_saved = sysreg_read(RSR_EX); - sysreg_write(RAR_EX, trampoline_addr); - sysreg_write(RSR_EX, (MODE_EXCEPTION - | SR_EM | SR_GM)); - BUG_ON(ti->rsr_saved & MODE_MASK); - } - - /* - * If we stepped into a system call, we - * shouldn't do a single step after we return - * since the return address is right after the - * "scall" instruction we were told to step - * over. - */ - if ((regs->sr & MODE_MASK) == MODE_SUPERVISOR) { - pr_debug("Supervisor; no single step\n"); - clear_ti_thread_flag(ti, TIF_SINGLE_STEP); - } - - ctrl = ocd_read(DC); - ctrl &= ~(1 << OCD_DC_SS_BIT); - ocd_write(DC, ctrl); - - return regs; - } else { - printk(KERN_ERR "Unexpected OCD_DS value: 0x%08x\n", - status); - printk(KERN_ERR "Thread flags: 0x%08lx\n", ti->flags); - die("Unhandled debug trap in kernel mode", - regs, SIGTRAP); - } - } else if (status & (1 << OCD_DS_SSS_BIT)) { - /* Single step in user mode */ - code = TRAP_TRACE; - - ctrl = ocd_read(DC); - ctrl &= ~(1 << OCD_DC_SS_BIT); - ocd_write(DC, ctrl); - } - - pr_debug("Sending SIGTRAP: code=%d PC=0x%08lx SR=0x%08lx\n", - code, regs->pc, regs->sr); - - clear_thread_flag(TIF_SINGLE_STEP); - _exception(SIGTRAP, regs, code, instruction_pointer(regs)); - - return regs; -} |