--- /dev/null
+/*
+ * 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;
+}
Code Review / kvmfornfv.git / blobdiff