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Diffstat (limited to 'arch/x86/um/ptrace_64.c')
| -rw-r--r-- | arch/x86/um/ptrace_64.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/arch/x86/um/ptrace_64.c b/arch/x86/um/ptrace_64.c new file mode 100644 index 00000000000..3b52bf0b418 --- /dev/null +++ b/arch/x86/um/ptrace_64.c @@ -0,0 +1,271 @@ +/* + * Copyright 2003 PathScale, Inc. + * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + * + * Licensed under the GPL + */ + +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/errno.h> +#define __FRAME_OFFSETS +#include <asm/ptrace.h> +#include <asm/uaccess.h> + +/* + * determines which flags the user has access to. + * 1 = access 0 = no access + */ +#define FLAG_MASK 0x44dd5UL + +static const int reg_offsets[] = +{ + [R8 >> 3] = HOST_R8, + [R9 >> 3] = HOST_R9, + [R10 >> 3] = HOST_R10, + [R11 >> 3] = HOST_R11, + [R12 >> 3] = HOST_R12, + [R13 >> 3] = HOST_R13, + [R14 >> 3] = HOST_R14, + [R15 >> 3] = HOST_R15, + [RIP >> 3] = HOST_IP, + [RSP >> 3] = HOST_SP, + [RAX >> 3] = HOST_AX, + [RBX >> 3] = HOST_BX, + [RCX >> 3] = HOST_CX, + [RDX >> 3] = HOST_DX, + [RSI >> 3] = HOST_SI, + [RDI >> 3] = HOST_DI, + [RBP >> 3] = HOST_BP, + [CS >> 3] = HOST_CS, + [SS >> 3] = HOST_SS, + [FS_BASE >> 3] = HOST_FS_BASE, + [GS_BASE >> 3] = HOST_GS_BASE, + [DS >> 3] = HOST_DS, + [ES >> 3] = HOST_ES, + [FS >> 3] = HOST_FS, + [GS >> 3] = HOST_GS, + [EFLAGS >> 3] = HOST_EFLAGS, + [ORIG_RAX >> 3] = HOST_ORIG_AX, +}; + +int putreg(struct task_struct *child, int regno, unsigned long value) +{ +#ifdef TIF_IA32 + /* + * Some code in the 64bit emulation may not be 64bit clean. + * Don't take any chances. + */ + if (test_tsk_thread_flag(child, TIF_IA32)) + value &= 0xffffffff; +#endif + switch (regno) { + case R8: + case R9: + case R10: + case R11: + case R12: + case R13: + case R14: + case R15: + case RIP: + case RSP: + case RAX: + case RBX: + case RCX: + case RDX: + case RSI: + case RDI: + case RBP: + case ORIG_RAX: + break; + + case FS: + case GS: + case DS: + case ES: + case SS: + case CS: + if (value && (value & 3) != 3) + return -EIO; + value &= 0xffff; + break; + + case FS_BASE: + case GS_BASE: + if (!((value >> 48) == 0 || (value >> 48) == 0xffff)) + return -EIO; + break; + + case EFLAGS: + value &= FLAG_MASK; + child->thread.regs.regs.gp[HOST_EFLAGS] |= value; + return 0; + + default: + panic("Bad register in putreg(): %d\n", regno); + } + + child->thread.regs.regs.gp[reg_offsets[regno >> 3]] = value; + return 0; +} + +int poke_user(struct task_struct *child, long addr, long data) +{ + if ((addr & 3) || addr < 0) + return -EIO; + + if (addr < MAX_REG_OFFSET) + return putreg(child, addr, data); + else if ((addr >= offsetof(struct user, u_debugreg[0])) && + (addr <= offsetof(struct user, u_debugreg[7]))) { + addr -= offsetof(struct user, u_debugreg[0]); + addr = addr >> 2; + if ((addr == 4) || (addr == 5)) + return -EIO; + child->thread.arch.debugregs[addr] = data; + return 0; + } + return -EIO; +} + +unsigned long getreg(struct task_struct *child, int regno) +{ + unsigned long mask = ~0UL; +#ifdef TIF_IA32 + if (test_tsk_thread_flag(child, TIF_IA32)) + mask = 0xffffffff; +#endif + switch (regno) { + case R8: + case R9: + case R10: + case R11: + case R12: + case R13: + case R14: + case R15: + case RIP: + case RSP: + case RAX: + case RBX: + case RCX: + case RDX: + case RSI: + case RDI: + case RBP: + case ORIG_RAX: + case EFLAGS: + case FS_BASE: + case GS_BASE: + break; + case FS: + case GS: + case DS: + case ES: + case SS: + case CS: + mask = 0xffff; + break; + default: + panic("Bad register in getreg: %d\n", regno); + } + return mask & child->thread.regs.regs.gp[reg_offsets[regno >> 3]]; +} + +int peek_user(struct task_struct *child, long addr, long data) +{ + /* read the word at location addr in the USER area. */ + unsigned long tmp; + + if ((addr & 3) || addr < 0) + return -EIO; + + tmp = 0; /* Default return condition */ + if (addr < MAX_REG_OFFSET) + tmp = getreg(child, addr); + else if ((addr >= offsetof(struct user, u_debugreg[0])) && + (addr <= offsetof(struct user, u_debugreg[7]))) { + addr -= offsetof(struct user, u_debugreg[0]); + addr = addr >> 2; + tmp = child->thread.arch.debugregs[addr]; + } + return put_user(tmp, (unsigned long *) data); +} + +/* XXX Mostly copied from sys-i386 */ +int is_syscall(unsigned long addr) +{ + unsigned short instr; + int n; + + n = copy_from_user(&instr, (void __user *) addr, sizeof(instr)); + if (n) { + /* + * access_process_vm() grants access to vsyscall and stub, + * while copy_from_user doesn't. Maybe access_process_vm is + * slow, but that doesn't matter, since it will be called only + * in case of singlestepping, if copy_from_user failed. + */ + n = access_process_vm(current, addr, &instr, sizeof(instr), 0); + if (n != sizeof(instr)) { + printk("is_syscall : failed to read instruction from " + "0x%lx\n", addr); + return 1; + } + } + /* sysenter */ + return instr == 0x050f; +} + +static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child) +{ + int err, n, cpu = ((struct thread_info *) child->stack)->cpu; + long fpregs[HOST_FP_SIZE]; + + BUG_ON(sizeof(*buf) != sizeof(fpregs)); + err = save_fp_registers(userspace_pid[cpu], fpregs); + if (err) + return err; + + n = copy_to_user(buf, fpregs, sizeof(fpregs)); + if (n > 0) + return -EFAULT; + + return n; +} + +static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child) +{ + int n, cpu = ((struct thread_info *) child->stack)->cpu; + long fpregs[HOST_FP_SIZE]; + + BUG_ON(sizeof(*buf) != sizeof(fpregs)); + n = copy_from_user(fpregs, buf, sizeof(fpregs)); + if (n > 0) + return -EFAULT; + + return restore_fp_registers(userspace_pid[cpu], fpregs); +} + +long subarch_ptrace(struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + int ret = -EIO; + void __user *datap = (void __user *) data; + + switch (request) { + case PTRACE_GETFPREGS: /* Get the child FPU state. */ + ret = get_fpregs(datap, child); + break; + case PTRACE_SETFPREGS: /* Set the child FPU state. */ + ret = set_fpregs(datap, child); + break; + case PTRACE_ARCH_PRCTL: + /* XXX Calls ptrace on the host - needs some SMP thinking */ + ret = arch_prctl(child, data, (void __user *) addr); + break; + } + + return ret; +} |