1 files changed, 198 insertions, 0 deletions

diff --git a/arch/um/sys-x86_64/ptrace.c b/arch/um/sys-x86_64/ptrace.c
new file mode 100644
index 00000000000..4005506834f
--- /dev/null
+++ b/arch/um/sys-x86_64/ptrace.c
@@ -0,0 +1,198 @@
+/*
+ * 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
+
+int putreg(struct task_struct *child, int regno, unsigned long value)
+{
+        unsigned long tmp;
+
+#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 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;
+                tmp = PT_REGS_EFLAGS(&child->thread.regs) & ~FLAG_MASK;
+                value |= tmp;
+                break;
+        }
+
+        PT_REGS_SET(&child->thread.regs, regno, 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 retval = ~0UL;
+        switch (regno) {
+        case FS:
+        case GS:
+        case DS:
+        case ES:
+        case SS:
+        case CS:
+                retval = 0xffff;
+                /* fall through */
+        default:
+                retval &= PT_REG(&child->thread.regs, regno);
+#ifdef TIF_IA32
+                if (test_tsk_thread_flag(child, TIF_IA32))
+                        retval &= 0xffffffff;
+#endif
+        }
+        return retval;
+}
+
+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;
+}