From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/m32r/kernel/ptrace.c | 829 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 829 insertions(+) create mode 100644 arch/m32r/kernel/ptrace.c (limited to 'arch/m32r/kernel/ptrace.c') diff --git a/arch/m32r/kernel/ptrace.c b/arch/m32r/kernel/ptrace.c new file mode 100644 index 000000000000..8b40f362dd6f --- /dev/null +++ b/arch/m32r/kernel/ptrace.c @@ -0,0 +1,829 @@ +/* + * linux/arch/m32r/kernel/ptrace.c + * + * Copyright (C) 2002 Hirokazu Takata, Takeo Takahashi + * Copyright (C) 2004 Hirokazu Takata, Kei Sakamoto + * + * Original x86 implementation: + * By Ross Biro 1/23/92 + * edited by Linus Torvalds + * + * Some code taken from sh version: + * Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka + * Some code taken from arm version: + * Copyright (C) 2000 Russell King + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include + +/* + * Get the address of the live pt_regs for the specified task. + * These are saved onto the top kernel stack when the process + * is not running. + * + * Note: if a user thread is execve'd from kernel space, the + * kernel stack will not be empty on entry to the kernel, so + * ptracing these tasks will fail. + */ +static inline struct pt_regs * +get_user_regs(struct task_struct *task) +{ + return (struct pt_regs *) + ((unsigned long)task->thread_info + THREAD_SIZE + - sizeof(struct pt_regs)); +} + +/* + * This routine will get a word off of the process kernel stack. + */ +static inline unsigned long int +get_stack_long(struct task_struct *task, int offset) +{ + unsigned long *stack; + + stack = (unsigned long *)get_user_regs(task); + + return stack[offset]; +} + +/* + * This routine will put a word on the process kernel stack. + */ +static inline int +put_stack_long(struct task_struct *task, int offset, unsigned long data) +{ + unsigned long *stack; + + stack = (unsigned long *)get_user_regs(task); + stack[offset] = data; + + return 0; +} + +static int reg_offset[] = { + PT_R0, PT_R1, PT_R2, PT_R3, PT_R4, PT_R5, PT_R6, PT_R7, + PT_R8, PT_R9, PT_R10, PT_R11, PT_R12, PT_FP, PT_LR, PT_SPU, +}; + +/* + * Read the word at offset "off" into the "struct user". We + * actually access the pt_regs stored on the kernel stack. + */ +static int ptrace_read_user(struct task_struct *tsk, unsigned long off, + unsigned long __user *data) +{ + unsigned long tmp; +#ifndef NO_FPU + struct user * dummy = NULL; +#endif + + if ((off & 3) || (off < 0) || (off > sizeof(struct user) - 3)) + return -EIO; + + off >>= 2; + switch (off) { + case PT_EVB: + __asm__ __volatile__ ( + "mvfc %0, cr5 \n\t" + : "=r" (tmp) + ); + break; + case PT_CBR: { + unsigned long psw; + psw = get_stack_long(tsk, PT_PSW); + tmp = ((psw >> 8) & 1); + } + break; + case PT_PSW: { + unsigned long psw, bbpsw; + psw = get_stack_long(tsk, PT_PSW); + bbpsw = get_stack_long(tsk, PT_BBPSW); + tmp = ((psw >> 8) & 0xff) | ((bbpsw & 0xff) << 8); + } + break; + case PT_PC: + tmp = get_stack_long(tsk, PT_BPC); + break; + case PT_BPC: + off = PT_BBPC; + /* fall through */ + default: + if (off < (sizeof(struct pt_regs) >> 2)) + tmp = get_stack_long(tsk, off); +#ifndef NO_FPU + else if (off >= (long)(&dummy->fpu >> 2) && + off < (long)(&dummy->u_fpvalid >> 2)) { + if (!tsk_used_math(tsk)) { + if (off == (long)(&dummy->fpu.fpscr >> 2)) + tmp = FPSCR_INIT; + else + tmp = 0; + } else + tmp = ((long *)(&tsk->thread.fpu >> 2)) + [off - (long)&dummy->fpu]; + } else if (off == (long)(&dummy->u_fpvalid >> 2)) + tmp = !!tsk_used_math(tsk); +#endif /* not NO_FPU */ + else + tmp = 0; + } + + return put_user(tmp, data); +} + +static int ptrace_write_user(struct task_struct *tsk, unsigned long off, + unsigned long data) +{ + int ret = -EIO; +#ifndef NO_FPU + struct user * dummy = NULL; +#endif + + if ((off & 3) || off < 0 || + off > sizeof(struct user) - 3) + return -EIO; + + off >>= 2; + switch (off) { + case PT_EVB: + case PT_BPC: + case PT_SPI: + /* We don't allow to modify evb. */ + ret = 0; + break; + case PT_PSW: + case PT_CBR: { + /* We allow to modify only cbr in psw */ + unsigned long psw; + psw = get_stack_long(tsk, PT_PSW); + psw = (psw & ~0x100) | ((data & 1) << 8); + ret = put_stack_long(tsk, PT_PSW, psw); + } + break; + case PT_PC: + off = PT_BPC; + data &= ~1; + /* fall through */ + default: + if (off < (sizeof(struct pt_regs) >> 2)) + ret = put_stack_long(tsk, off, data); +#ifndef NO_FPU + else if (off >= (long)(&dummy->fpu >> 2) && + off < (long)(&dummy->u_fpvalid >> 2)) { + set_stopped_child_used_math(tsk); + ((long *)&tsk->thread.fpu) + [off - (long)&dummy->fpu] = data; + ret = 0; + } else if (off == (long)(&dummy->u_fpvalid >> 2)) { + conditional_stopped_child_used_math(data, tsk); + ret = 0; + } +#endif /* not NO_FPU */ + break; + } + + return ret; +} + +/* + * Get all user integer registers. + */ +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(struct pt_regs)) ? -EFAULT : 0; +} + +/* + * Set all user integer registers. + */ +static int ptrace_setregs(struct task_struct *tsk, void __user *uregs) +{ + struct pt_regs newregs; + int ret; + + ret = -EFAULT; + if (copy_from_user(&newregs, uregs, sizeof(struct pt_regs)) == 0) { + struct pt_regs *regs = get_user_regs(tsk); + *regs = newregs; + ret = 0; + } + + return ret; +} + + +static inline int +check_condition_bit(struct task_struct *child) +{ + return (int)((get_stack_long(child, PT_PSW) >> 8) & 1); +} + +static int +check_condition_src(unsigned long op, unsigned long regno1, + unsigned long regno2, struct task_struct *child) +{ + unsigned long reg1, reg2; + + reg2 = get_stack_long(child, reg_offset[regno2]); + + switch (op) { + case 0x0: /* BEQ */ + reg1 = get_stack_long(child, reg_offset[regno1]); + return reg1 == reg2; + case 0x1: /* BNE */ + reg1 = get_stack_long(child, reg_offset[regno1]); + return reg1 != reg2; + case 0x8: /* BEQZ */ + return reg2 == 0; + case 0x9: /* BNEZ */ + return reg2 != 0; + case 0xa: /* BLTZ */ + return (int)reg2 < 0; + case 0xb: /* BGEZ */ + return (int)reg2 >= 0; + case 0xc: /* BLEZ */ + return (int)reg2 <= 0; + case 0xd: /* BGTZ */ + return (int)reg2 > 0; + default: + /* never reached */ + return 0; + } +} + +static void +compute_next_pc_for_16bit_insn(unsigned long insn, unsigned long pc, + unsigned long *next_pc, + struct task_struct *child) +{ + unsigned long op, op2, op3; + unsigned long disp; + unsigned long regno; + int parallel = 0; + + if (insn & 0x00008000) + parallel = 1; + if (pc & 3) + insn &= 0x7fff; /* right slot */ + else + insn >>= 16; /* left slot */ + + op = (insn >> 12) & 0xf; + op2 = (insn >> 8) & 0xf; + op3 = (insn >> 4) & 0xf; + + if (op == 0x7) { + switch (op2) { + case 0xd: /* BNC */ + case 0x9: /* BNCL */ + if (!check_condition_bit(child)) { + disp = (long)(insn << 24) >> 22; + *next_pc = (pc & ~0x3) + disp; + return; + } + break; + case 0x8: /* BCL */ + case 0xc: /* BC */ + if (check_condition_bit(child)) { + disp = (long)(insn << 24) >> 22; + *next_pc = (pc & ~0x3) + disp; + return; + } + break; + case 0xe: /* BL */ + case 0xf: /* BRA */ + disp = (long)(insn << 24) >> 22; + *next_pc = (pc & ~0x3) + disp; + return; + break; + } + } else if (op == 0x1) { + switch (op2) { + case 0x0: + if (op3 == 0xf) { /* TRAP */ +#if 1 + /* pass through */ +#else + /* kernel space is not allowed as next_pc */ + unsigned long evb; + unsigned long trapno; + trapno = insn & 0xf; + __asm__ __volatile__ ( + "mvfc %0, cr5\n" + :"=r"(evb) + : + ); + *next_pc = evb + (trapno << 2); + return; +#endif + } else if (op3 == 0xd) { /* RTE */ + *next_pc = get_stack_long(child, PT_BPC); + return; + } + break; + case 0xc: /* JC */ + if (op3 == 0xc && check_condition_bit(child)) { + regno = insn & 0xf; + *next_pc = get_stack_long(child, + reg_offset[regno]); + return; + } + break; + case 0xd: /* JNC */ + if (op3 == 0xc && !check_condition_bit(child)) { + regno = insn & 0xf; + *next_pc = get_stack_long(child, + reg_offset[regno]); + return; + } + break; + case 0xe: /* JL */ + case 0xf: /* JMP */ + if (op3 == 0xc) { /* JMP */ + regno = insn & 0xf; + *next_pc = get_stack_long(child, + reg_offset[regno]); + return; + } + break; + } + } + if (parallel) + *next_pc = pc + 4; + else + *next_pc = pc + 2; +} + +static void +compute_next_pc_for_32bit_insn(unsigned long insn, unsigned long pc, + unsigned long *next_pc, + struct task_struct *child) +{ + unsigned long op; + unsigned long op2; + unsigned long disp; + unsigned long regno1, regno2; + + op = (insn >> 28) & 0xf; + if (op == 0xf) { /* branch 24-bit relative */ + op2 = (insn >> 24) & 0xf; + switch (op2) { + case 0xd: /* BNC */ + case 0x9: /* BNCL */ + if (!check_condition_bit(child)) { + disp = (long)(insn << 8) >> 6; + *next_pc = (pc & ~0x3) + disp; + return; + } + break; + case 0x8: /* BCL */ + case 0xc: /* BC */ + if (check_condition_bit(child)) { + disp = (long)(insn << 8) >> 6; + *next_pc = (pc & ~0x3) + disp; + return; + } + break; + case 0xe: /* BL */ + case 0xf: /* BRA */ + disp = (long)(insn << 8) >> 6; + *next_pc = (pc & ~0x3) + disp; + return; + } + } else if (op == 0xb) { /* branch 16-bit relative */ + op2 = (insn >> 20) & 0xf; + switch (op2) { + case 0x0: /* BEQ */ + case 0x1: /* BNE */ + case 0x8: /* BEQZ */ + case 0x9: /* BNEZ */ + case 0xa: /* BLTZ */ + case 0xb: /* BGEZ */ + case 0xc: /* BLEZ */ + case 0xd: /* BGTZ */ + regno1 = ((insn >> 24) & 0xf); + regno2 = ((insn >> 16) & 0xf); + if (check_condition_src(op2, regno1, regno2, child)) { + disp = (long)(insn << 16) >> 14; + *next_pc = (pc & ~0x3) + disp; + return; + } + break; + } + } + *next_pc = pc + 4; +} + +static inline void +compute_next_pc(unsigned long insn, unsigned long pc, + unsigned long *next_pc, struct task_struct *child) +{ + if (insn & 0x80000000) + compute_next_pc_for_32bit_insn(insn, pc, next_pc, child); + else + compute_next_pc_for_16bit_insn(insn, pc, next_pc, child); +} + +static int +register_debug_trap(struct task_struct *child, unsigned long next_pc, + unsigned long next_insn, unsigned long *code) +{ + struct debug_trap *p = &child->thread.debug_trap; + unsigned long addr = next_pc & ~3; + + if (p->nr_trap == MAX_TRAPS) { + printk("kernel BUG at %s %d: p->nr_trap = %d\n", + __FILE__, __LINE__, p->nr_trap); + return -1; + } + p->addr[p->nr_trap] = addr; + p->insn[p->nr_trap] = next_insn; + p->nr_trap++; + if (next_pc & 3) { + *code = (next_insn & 0xffff0000) | 0x10f1; + /* xxx --> TRAP1 */ + } else { + if ((next_insn & 0x80000000) || (next_insn & 0x8000)) { + *code = 0x10f17000; + /* TRAP1 --> NOP */ + } else { + *code = (next_insn & 0xffff) | 0x10f10000; + /* TRAP1 --> xxx */ + } + } + return 0; +} + +static int +unregister_debug_trap(struct task_struct *child, unsigned long addr, + unsigned long *code) +{ + struct debug_trap *p = &child->thread.debug_trap; + int i; + + /* Search debug trap entry. */ + for (i = 0; i < p->nr_trap; i++) { + if (p->addr[i] == addr) + break; + } + if (i >= p->nr_trap) { + /* The trap may be requested from debugger. + * ptrace should do nothing in this case. + */ + return 0; + } + + /* Recover orignal instruction code. */ + *code = p->insn[i]; + + /* Shift debug trap entries. */ + while (i < p->nr_trap - 1) { + p->insn[i] = p->insn[i + 1]; + p->addr[i] = p->addr[i + 1]; + i++; + } + p->nr_trap--; + return 1; +} + +static void +unregister_all_debug_traps(struct task_struct *child) +{ + struct debug_trap *p = &child->thread.debug_trap; + int i; + + for (i = 0; i < p->nr_trap; i++) + access_process_vm(child, p->addr[i], &p->insn[i], sizeof(p->insn[i]), 1); + p->nr_trap = 0; +} + +static inline void +invalidate_cache(void) +{ +#if defined(CONFIG_CHIP_M32700) || defined(CONFIG_CHIP_OPSP) + + _flush_cache_copyback_all(); + +#else /* ! CONFIG_CHIP_M32700 */ + + /* Invalidate cache */ + __asm__ __volatile__ ( + "ldi r0, #-1 \n\t" + "ldi r1, #0 \n\t" + "stb r1, @r0 ; cache off \n\t" + "; \n\t" + "ldi r0, #-2 \n\t" + "ldi r1, #1 \n\t" + "stb r1, @r0 ; cache invalidate \n\t" + ".fillinsn \n" + "0: \n\t" + "ldb r1, @r0 ; invalidate check \n\t" + "bnez r1, 0b \n\t" + "; \n\t" + "ldi r0, #-1 \n\t" + "ldi r1, #1 \n\t" + "stb r1, @r0 ; cache on \n\t" + : : : "r0", "r1", "memory" + ); + /* FIXME: copying-back d-cache and invalidating i-cache are needed. + */ +#endif /* CONFIG_CHIP_M32700 */ +} + +/* Embed a debug trap (TRAP1) code */ +static int +embed_debug_trap(struct task_struct *child, unsigned long next_pc) +{ + unsigned long next_insn, code; + unsigned long addr = next_pc & ~3; + + if (access_process_vm(child, addr, &next_insn, sizeof(next_insn), 0) + != sizeof(next_insn)) { + return -1; /* error */ + } + + /* Set a trap code. */ + if (register_debug_trap(child, next_pc, next_insn, &code)) { + return -1; /* error */ + } + if (access_process_vm(child, addr, &code, sizeof(code), 1) + != sizeof(code)) { + return -1; /* error */ + } + return 0; /* success */ +} + +void +withdraw_debug_trap(struct pt_regs *regs) +{ + unsigned long addr; + unsigned long code; + + addr = (regs->bpc - 2) & ~3; + regs->bpc -= 2; + if (unregister_debug_trap(current, addr, &code)) { + access_process_vm(current, addr, &code, sizeof(code), 1); + invalidate_cache(); + } +} + +static void +init_debug_traps(struct task_struct *child) +{ + struct debug_trap *p = &child->thread.debug_trap; + int i; + p->nr_trap = 0; + for (i = 0; i < MAX_TRAPS; i++) { + p->addr[i] = 0; + p->insn[i] = 0; + } +} + + +/* + * Called by kernel/ptrace.c when detaching.. + * + * Make sure single step bits etc are not set. + */ +void ptrace_disable(struct task_struct *child) +{ + /* nothing to do.. */ +} + +static int +do_ptrace(long request, struct task_struct *child, long addr, long data) +{ + unsigned long tmp; + int ret; + + switch (request) { + /* + * read word at location "addr" in the child process. + */ + case PTRACE_PEEKTEXT: + case PTRACE_PEEKDATA: + ret = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); + if (ret == sizeof(tmp)) + ret = put_user(tmp,(unsigned long __user *) data); + else + ret = -EIO; + break; + + /* + * read the word at location addr in the USER area. + */ + case PTRACE_PEEKUSR: + ret = ptrace_read_user(child, addr, + (unsigned long __user *)data); + break; + + /* + * write the word at location addr. + */ + case PTRACE_POKETEXT: + case PTRACE_POKEDATA: + ret = access_process_vm(child, addr, &data, sizeof(data), 1); + if (ret == sizeof(data)) { + ret = 0; + if (request == PTRACE_POKETEXT) { + invalidate_cache(); + } + } else { + ret = -EIO; + } + break; + + /* + * write the word at location addr in the USER area. + */ + case PTRACE_POKEUSR: + ret = ptrace_write_user(child, addr, data); + break; + + /* + * continue/restart and stop at next (return from) syscall + */ + case PTRACE_SYSCALL: + case PTRACE_CONT: + ret = -EIO; + if ((unsigned long) data > _NSIG) + break; + if (request == PTRACE_SYSCALL) + set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + else + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + child->exit_code = data; + wake_up_process(child); + ret = 0; + break; + + /* + * make the child exit. Best I can do is send it a sigkill. + * perhaps it should be put in the status that it wants to + * exit. + */ + case PTRACE_KILL: { + ret = 0; + unregister_all_debug_traps(child); + invalidate_cache(); + if (child->exit_state == EXIT_ZOMBIE) /* already dead */ + break; + child->exit_code = SIGKILL; + wake_up_process(child); + break; + } + + /* + * execute single instruction. + */ + case PTRACE_SINGLESTEP: { + unsigned long next_pc; + unsigned long pc, insn; + + ret = -EIO; + if ((unsigned long) data > _NSIG) + break; + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + if ((child->ptrace & PT_DTRACE) == 0) { + /* Spurious delayed TF traps may occur */ + child->ptrace |= PT_DTRACE; + } + + /* Compute next pc. */ + pc = get_stack_long(child, PT_BPC); + + if (access_process_vm(child, pc&~3, &insn, sizeof(insn), 0) + != sizeof(insn)) + break; + + compute_next_pc(insn, pc, &next_pc, child); + if (next_pc & 0x80000000) + break; + + if (embed_debug_trap(child, next_pc)) + break; + + invalidate_cache(); + child->exit_code = data; + + /* give it a chance to run. */ + wake_up_process(child); + ret = 0; + break; + } + + /* + * detach a process that was attached. + */ + case PTRACE_DETACH: + ret = 0; + ret = ptrace_detach(child, data); + break; + + case PTRACE_GETREGS: + ret = ptrace_getregs(child, (void __user *)data); + break; + + case PTRACE_SETREGS: + ret = ptrace_setregs(child, (void __user *)data); + break; + + default: + ret = ptrace_request(child, request, addr, data); + break; + } + + return ret; +} + +asmlinkage int sys_ptrace(long request, long pid, long addr, long data) +{ + struct task_struct *child; + int ret; + + lock_kernel(); + ret = -EPERM; + if (request == PTRACE_TRACEME) { + /* are we already being traced? */ + if (current->ptrace & PT_PTRACED) + goto out; + /* set the ptrace bit in the process flags. */ + current->ptrace |= PT_PTRACED; + ret = 0; + goto out; + } + ret = -ESRCH; + read_lock(&tasklist_lock); + child = find_task_by_pid(pid); + if (child) + get_task_struct(child); + read_unlock(&tasklist_lock); + if (!child) + goto out; + + ret = -EPERM; + if (pid == 1) /* you may not mess with init */ + goto out; + + if (request == PTRACE_ATTACH) { + ret = ptrace_attach(child); + if (ret == 0) + init_debug_traps(child); + goto out_tsk; + } + + ret = ptrace_check_attach(child, request == PTRACE_KILL); + if (ret == 0) + ret = do_ptrace(request, child, addr, data); + +out_tsk: + put_task_struct(child); +out: + unlock_kernel(); + + return ret; +} + +/* notification of system call entry/exit + * - triggered by current->work.syscall_trace + */ +void do_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) { + send_sig(current->exit_code, current, 1); + current->exit_code = 0; + } +} -- cgit v1.2.3-55-g7522